Foliar Feeding of Gromor Nano DAP on Physiological, Biochemical and Nutritional Changes in Rice

Foliar Feeding of Gromor Nano DAP on Physiological, Biochemical and Nutritional Changes in Rice | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Foliar Feeding of Gromor Nano DAP on Physiological, Biochemical and Nutritional Changes in Rice Sharmila Rahale, K.S. Subramanian, M Kalarani, M Umapathy, J Mohanraj, and 2 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6238153/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Field experiments were conducted during two crop seasons ( Rabi 2023 and Kharif 2024) to determine physiological, biochemical and nutritional responses of rice to the foliar spray of nano DAP (nDAP) in comparison to conventional DAP. The data on SEM images showed that nDAP gets absorbed by leaves rapidly within 2 hours in comparison to cDAP (> 12 hrs). Combined application of 75% RDP with two rounds of nDAP at critical stages had significantly higher photosynthetic rates (3.4–7.7%), stomatal conductance (18–23%), transpiration rate (6–7%) and SPAD (12.9–16.6%) than cDAP spray. Nitrogen assimilatory enzymes NR (nDAP 21.6; cDAP 18.9 µg NO 2 g − 1 h − 1 ), GS (nDAP 240.8; 160.2 µmol g − 1 FW h − 1 ), GOGAT (nDAP 207.5; cDAP 194.4 µmol NADH g − 1 FW h − 1 ) and ASP (nDAP 654.2; cDAP 531.7 µmol g − 1 h − 1 ) activities were higher in nDAP than cDAP sprayed plants. Nano DAP sprayed rice plants had higher N and P contents in critical growth stages. Data showed that nDAP gets absorbed in the plant system rapidly and orchestrate the physiological processes and nitrogen and phosphorous assimilatory pathways that collectively contributed for the improved N and P contents. This one of the early reports suggesting insights involved in nDAP sprayed plants leading to nutrient status. Biological sciences/Plant sciences/Plant physiology Earth and environmental sciences/Environmental sciences nano DAP physiological biochemical nutritional responses rice Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. INTRODUCTION Phosphorous is one of the most critical essential nutrients required by crops which decides the crop productivity across the globe (Varshney et al., 2011). The P is highly immobile in soil and its availability is enigmatic due to the fixation (> 80%) in the soil as unavailable inorganic and organic forms (Timofeeva et al., 2022) besides runoff causing eutrophication in aquatic systems like lakes and rivers (Barathan et al., 2023). The radiotracer studies have precisely determined that the P use efficiencies in plants which hardly exceeds 18–20% (Subramanian and Kumaraswamy, 1989) and the remaining major portion of unutilized forms of P stays in the ecosystem causing environmental hazard. Thus, there is a need for a new paradigm in plant nutrient management holistically ensuring circular economy approach to achieve a set of desirable goals to target socioeconomic, environmental and health objectives (Dobermann et al., 2022). Phosphatic fertilizers are primarily manufactured from natural rock phosphates involving acidulation with concentrated sulfuric acids and the resultant products often associated with heavy metals and radioactive contaminants (Tayibi et al., 2009). The rock phosphates are natural reserve, non-renewable source and its deposits are fast depleting and a need for alternate route to develop P fertilizers. Further, import of phosphate rich rocks is facing a great deal of challenge as a recent development of war between Russia and Ukraine since 2022 that impeded the supply of raw materials for fertilizer production. India is dependent on imports nearly 5 million tonnes of phosphate rock, 2.5 million tonnes of phosphoric acid and 3 million tonnes of DAP annually during the year 2023–2024 (Mint, 2024). In the case of diammonium phosphate, around 60% of the supply is imported. This necessitates to go in for an alternate form fertilizer which is sustainable. In India, 10.53 million tonnes of DAP were consumed during 2022–2023 which was 13.5% higher than the previous years and the trend will continue to increase in the years to come (Annual Review of Fertilizer Production and Consumption 2022-23). To economize the P use and improve the P use efficiency is widely recommended for pulses (Krishna and Kaleeswari, 2018; Ashraf et al., 2024). However, it poses a practical difficulty of soaking overnight and the supernatant is filtered and sprayed on crops. To achieve balanced crop nutrition, DAP was more promoted by the Government of India than urea. One of the emerging areas appears to resolve the unresolved issues is nanotechnology which is widely being exploited in electronics, energy, environment, health sciences and agriculture (Ridhi et al., 2024). Nanotechnology is one of the fascinating fields of science which has a potential to manipulate atomic scale to develop processes and products involved in agricultural inputs that can be designed to minimize the losses and maximize the use efficiencies (Subramanian et al., 2015; El-Ramady et al., 2023). Considering the reviews and priority of India, major fertilizer companies like IFFCO and Coromandel International Limited were encouraged to produce nano-DAP to overcome the issue of imports and balanced crop nutrition (Business Standard, 2023) The Coromandel Gromor nano DAP was approved and notified (FCO, 2023). The nano phosphatic fertilizers developed using top down and bottom-up approaches have been evaluated in various crops such as rice (Saraiva et al., 2022), wheat (Poudel et al., 2023; Upadhyay et al., 2023), maize (Upadhyay et al., 2023), pearl millet (Upadhyay et al., 2023), mustard (Upadhyay et al., 2023), sunflower (Ernst et al., 2023) and tomato (Singh et al., 2021). Similarly, foliar spray of nano urea was tested in wheat (Kumar et al., 2023). Foliar spray of combined nano N and Nano-Zn has improved the yield and quality of fodder maize tested in northwestern plains of India. Abdel-Hakim et al. (2023) reported that the conjoint use of conventional fertilizers with nano-NPK fertilizers found to reduce the quantities of fertilizers by 75% or 50% of NPK requirements without significant adverse effects on the growth and productivity of lettuce cultivated in sandy soils. The literature review clearly indicated that the nano-fertilizers carrying single or multi-nutrients have the capability to improve the productivity of a wide array of crops while saving of fertilizers to the tune of 25–50% of the recommended dose of fertilizers without associated environmental hazard. The literature review strongly set the stage to undertake the research on nano-DAP in rice production system. Saraiva et al. (2022) have shown that the delivery of P in the form of slow-release nano-P fertilizer instead of conventional bulk fertilizers reduced the amount of nutrients applied and increased the absorption by rice crop. Further, combining fertilizer effect with chitosan a natural polymer and biostimulant (Iftime et al., 2024) which commonly used as an encapsulant for the development of nano-fertilizers (Hamed et al., 2024) has an added benefit of plant protection against diseases and increase the resilience to stress (Hashim et al., 2024). In another study, Miranda-Villagomez et al. (2019) have demonstrated that nano-KH 2 PO 4 with trypsin promoted physiological efficiency for both roots and shoots of rice which consequently enhanced the plant biomass. Further, they established a close correlation between P accumulation in roots and shoots and P concentration. Poudel et al. (2023) reported that foliar feeding P in the form of nano-P combined with conventional DAP saved 25% of fertilizer P while reducing the P leaching into the groundwater and maintaining or increasing the wheat crop yield in the soils of North Gangetic Plains in India. Singh et al. (2021) have stated that the cryo-milled nano DAP has a particle size of 378 nm which is 5000 times smaller and specific surface area of 24.6 m 2 g − 1 which is 14,000 times greater than conventional DAP. Such an extensive surface area of nano-DAP facilitated the availability of P and enhanced the growth of wheat and tomato even with 75% of recommended dose of P for both the test crops. This assisted nano DAP fertilized plants to produce higher biomass production, longer shoots, shorter roots and less anthocyanin pigmentation even with 75% RDP in comparison to conventional DAP. The present study was conducted under field conditions to determine the physiological, biochemical and nutritional responses in rice plants fertilized with foliar spray of conventional DAP or nano-DAP (twice) in combination with 75% RDP, 100% RDP and control. In the both the set of field experiments, physiological (photosynthetic rate, stomatal conductance, transpiration rate, relative water content, membrane integrity), biochemical (nitrate reductase, glutamine synthetase, glutamate synthase, acid phosphatase, proteins, chlorophyll content, anthocyanin content) and nutritional (SPAD value, N & P contents, nutrient uptake) were measured at the active tillering and panicle initiation stages. Further, in the second set of experiment, high resolution imaging of nano DAP sprayed leaves was done to determine the absorption pattern in the rice leaves and complete key N assimilatory enzymes. The objective of the study is based on the hypothesis that nano-DAP sprays during the critical growth stages of rice crop orchestrates physiological, biochemical and nutritional changes that collectively contribute for the improved crop nutrition. These processes assist in economizing the P use through the foliar spray of nano DAP. 2. Results 2.1. Characteristics of Nano DAP The nDAP was analysed for its characteristics that fulfilled the stipulated specifications of FCO such as pH, hydrodynamic size (PSA), physical size (TEM), zeta potential, specific gravity, viscosity and nutrient concentrations. The nDAP particles were in the hydrodynamic and physical sizes in the range of 13.3–33.5 nm and 43.7 nm, respectively. The nDAP had zeta potential (+ 1.13 mV), acidic in pH (4.74), viscosity (8.86 cps), specific gravity (1.03 g cc − 1 ), nitrogen (2.66%) and phosphorous (4.93% P 2 O 5 ) (Table 1 ). Table 1 Specifications of Gromor nano DAP and actual values measured in the nano-DAP used in the experiments No. Parameters Specifications Values measured 1 Appearance Opalescent / light milky white solution Light milky white solution 2 Nitrogen concentration % min 1–2% 2.66 3 P 2 O 5 concentration % min 3–5% 4.93 4 pH (liquid fertilizer sample measured directly) 4.5-6.0 4.74 5 Specific gravity 1–1.1 1.03 6 Viscosity 5–20 cps 8.86 7 Physical Particle size (TEM) 10–70 nm 13.3–30.9 8 Hydrodynamic Particle Size (PSA) < 100 nm 43.7 9 Surface Charge /Zeta Potential (mV) 1–5 1.13 2.2. Physiological Changes in Rice 2.2.1. Photosynthetic Rate, Stomatal Conductance, Transpiration Rate and Water Use Efficiency The photosynthetic rates of nDAP sprayed rice plants had significantly higher values after the active tillering (29.2) and panicle initiation (32.1 µmol m − 2 s − 1 ) stages than cDAP (28.7; 30.5 µmol m − 2 s − 1 ) sprayed treatment during Rabi 2023 (Table 2 ). After the second spray, the percentage increase in photosynthetic rates in nDAP sprayed rice leaves were higher by 4.98, 4.04 and 42.7 in comparison to cDAP, 100% RDP and control, respectively. Similar trend of response was observed at the Kharif 2024 as well. The pooled analysis of data has clearly shown that nDAP sprayed plants registered higher photosynthetic rates regardless of growth stages than other treatments, but the response was more pronounced at the PI stage. Table 2 Photosynthetic rate (µmol m − 2 s − 1 ), stomatal conductance (mmol m − 2 s − 1 ), transpiration rate (mmol m − 2 s − 1 ) and water use efficiency (µmol CO 2 mmol − 1 H 2 O) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023) and Experiment II (Kharif 2024) separately Treatments Photosynthetic rate (µmol m − 2 s − 1 ) Stomatal conductance (mmol m − 2 s − 1 ) Transpiration rate (mmol m − 2 s − 1 ) WUE (µmol CO 2 mmol − 1 H 2 O) AT PI AT PI AT PI AT PI Rabi 2023 T1–0% RDP 13.8 d 18.4 c 108.5 d 150.6 d 2.00 d 3.10 c 6.91 b 5.94 a T2–100% RDP 27.4 c 30.8 b 191.1 c 207.3 c 3.47 c 6.68 a 7.90 a 4.61 b T3–75% RDP + 1% DAP FS@25th and 45th DAT 28.7 b 30.5 b 264.7 b 229.6 b 5.25 b 6.18 b 5.47 c 4.94 c T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 29.2 a 32.1 a 288.0 a 302.4a 5.45 a 6.24 b 5.35 c 5.14 d SEd 0.21 0.23 1.87 1.77 0.36 0.04 0.04 0.40 CD ( p ≤ 0.05) 0.46 0.50 4.09 3.87 0.79 0.10 0.10 0.88 Kharif 2024 T1–0% RDP 18.8a 22.2 c 286.2a 319.2 c 3.2 b 3.8 d 6.0a 5.9 d T2–100% RDP 24.6a 29.9 a 362.0a 387.4 b 3.6 a 4.2 b 7.6a 7.6 a T3–75% RDP + 1% DAP FS@25th and 45th DAT 25.2a 27.1 b 261.8a 308.5 d 3.2b 3.9 c 8.2a 7.1 b T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 26.5a 30.3 a 357.6a 398.7 a 3.6 a 4.4 a 7.5a 6.9 c SEd 3.04 0.19 68.13 2.49 0.40 0.01 1.29 0.04 CD ( p ≤ 0.05) 6.64 0.42 148.4 ns 5.43 0.87 0.03 2.82 ns 0.09 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting The nDAP sprayed rice plants had significantly higher stomatal conductance at the active tillering (288) and panicle initiation (302 µmol m − 2 s − 1 ) stages than cDAP (265; 230 mmol m − 2 s − 1 ) sprayed treatment during Rabi 2023 (Table 2 ). After the two sprays, the nDAP sprayed plants had registered higher values by 24, 31.4 and 50% than the cDAP, 100% RDP and control, respectively. Transpiration rate (TR) registered in treatments received foliar spray of cDAP and nDAP along with 75% RDP measured at the active tillering and panicle initiation stages are presented (Table 2 ). During Rabi 2023, the treatment received 75% RDP along with foliar spray of nDAP recorded the highest transpiration rates of 5.45 and 6.24 mmol H 2 O m − 2 s − 1 at the AT and PI stages, respectively. But the values in nDAP sprayed plants were significantly different at AT and comparable at PI with the cDAP sprayed plants. Similar trend of response was exhibited during Kharif 2024, but the values are smaller than Rabi 2024 irrespective of the treatments. Pooled data suggest that nDAP sprayed plants had higher TR regardless of stage, but the values are significantly higher at PI stage. The water use efficiency (WUE) as the measure of photosynthetic rates per unit of water utilized was recorded at AT and PI after the nDAP and cDAP sprayed rice plants during Rabi 2023 and Kharif 2024 seasons (Table 2 ). The data indicated that both nDAP and cDAP sprayed rice plants had significantly lower WUE than 100% RDP and control especially at the AT stage during Rabi 2023 and the data were not significant during Kharif 2024. However, at the PI stage, nDAP and cDAP sprayed plants had significantly higher WUE than 100% RDP. The pooled data indicated significantly lower values in nDAP than cDAP sprayed plants at AT and both were similar at PI stage. 2.2.2. SPAD value, total chlorophyll and anthocyanin content The SPAD value, total chlorophyll and anthocyanin contents measured during active tillering (AT) and panicle initiation (PI) stages during Rabi 2023 and Kharif 2024 are presented in Table 3 . During Rabi 2023, SPAD values were significantly higher in nDAP (59.2; 59.5) than cDAP (45.4; 49.9) sprayed rice leaves at AT and PI stages, respectively. The percentage increase in SPAD values in 75% RDP + nDAP were 18.3 and 15.6 in comparison to 100% RDP at AT and PI, respectively. During Kharif 2024, such pronounced response was observed at the PI stage only. The pooled data also indicated an increase of 7–9 units of SPAD values in comparison to cDAP sprayed plants and are significantly higher in nDAP than cDAP sprayed plants regardless of growth stages. In correspondence with the SPAD values, total chlorophyll concentrations in nDAP sprayed plants (0.65; 1.88) is significantly higher than cDAP (0.48; 1.61 mg/g FW) at AT and PI stages during Rabi 2023, but the values were lower than 100% RDP (Table 3 ). Table 3 SPAD value, Chlorophyll (mg/g FW) and Anthocyanin concentrations (mg/g FM) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately Treatments SPAD value Total Chlorophyll (mg/g FW) Anthocyanin (mg/g FW) 1st spray 2nd spray 1st spray 2nd spray 1st spray 2nd spray Rabi 2023 T1–0% RDP 45.3 c 46.3 c 0.39 d 1.08 d 0.026 a 0.042 a T2–100% RDP 48.4 b 50.2 b 0.79 a 1.72 b 0.021 c 0.013 c T3–75% RDP + 1% DAP FS@25th and 45th DAT 45.4 c 49.9 b 0.48 c 1.61 c 0.022 b 0.017 b T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 59.23 a 59.51 a 0.65 b 1.88 a 0.016 d 0.011 d SEd 0.37 0.40 0.044 0.01 0.0017 0.0018 CD ( p ≤ 0.05) 0.82 0.87 0.01 0.02 0.0038 0.0039 Kharif 2024 T1–0% RDP 40.1 b 43.7 c 0.34 c 1.15d 0.022 a 0.038 a T2–100% RDP 50.9 a 52.3 a 0.73 a 1.68b 0.019 c 0.012 d T3–75% RDP + 1% DAP FS@25th and 45th DAT 45.2 ab 47.4 b 0.51 b 1.36c 0.020 b 0.018 b T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 49.3 ab 52.1 a 0.71 a 1.71 a 0.015 d 0.010 c SEd 3.79 0.23 0.01 0.01 0.0001 0.001 CD ( p ≤ 0.05) 8.26 ns 0.51 0.02 0.03 0.001 0.002 Pooled Mean T1–0% RDP 42.7 c 45.0 d 0.36 d 1.11 d 0.024 a 0.040 a T2–100% RDP 49.6 ab 51.2 b 0.76 a 1.70 b 0.020 c 0.013 c T3–75% RDP + 1% DAP FS@25th and 45th DAT 45.2 bc 48.6 c 0.49 c 1.48 c 0.021 b 0.017 b T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 54.2 a 55.8 a 0.68 b 1.79 a 0.015 d 0.010 d SEd 2.69 0.33 0.007 0.01 0.0009 0.0014 CD ( p ≤ 0.05) 5.56 0.68 0.01 0.02 0.002 0.0029 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting The anthocyanin content of the nDAP and cDAP sprayed rice plants was measured and the data are presented in Table 3 . In contrast to the chlorophyll content, anthocyanin content in nDAP sprayed rice plants was significantly lower at AT and PI irrespective of the cropping season. Pooled data have revealed that anthocyanin content was significantly lower in nDAP than cDAP sprayed plants at both AT and PI stages. 2.2.3. Electrolyte leakage and relative water content (RWC) The electrolyte leakage was measured in nDAP and cDAP sprayed plants in order determine whether the plants are stressed (Table 4 ). The electrolyte leakage percentage lowest at AT and PI stages regardless of seasons. Indeed, the values are significantly lower in nDAP than cDAP in both the stages and seasons. The pooled data have clearly and consistently indicated that electrolyte leakage was significantly lower in nDAP than cDAP regardless of growth stages. Table 4 Electrolyte leakage and relative water content (RWC) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately Treatments Electrolyte Leakage (%) RWC (%) 1st spray 2nd spray 1st spray 2nd spray Rabi 2023 T1–0% RDP 9.21 a 10.24 a 80.1 b 80.2 b T2–100% RDP 7.62 c 9.87 b 83.3 a 82.1 a T3–75% RDP + 1% DAP FS@25th and 45th DAT 7.98 b 9.95 b 83.9 a 81.6 ab T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 07.42 d 8.79 c 84.5 a 82.5 a SEd 0.06 0.07 0.66 0.65 CD ( p ≤ 0.05) 0.14 0.17 1.45 1.42 Kharif 2024 T1–0% RDP 10.5 a 10.8 a 82.2 d 83.8 d T2–100% RDP 8.4 c 8.5 c 83.8 b 85.4 b T3–75% RDP + 1% DAP FS@25th and 45th DAT 9.2 b 9.5 b 83.1 c 84.1 c T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 8.1 d 8.2 d 84.4 a 85.7 a SEd 0.06 0.07 0.05 0.04 CD ( p ≤ 0.05) 0.13 0.15 0.12 0.09 Pooled Mean T1–0% RDP 9.85 a 10.5 a 81.2 c 82.0 b T2–100% RDP 8.01 c 9.18 c 83.6 b 83.8 a T3–75% RDP + 1% DAP FS@25th and 45th DAT 8.59 b 9.72 b 83.3 b 82.9 b T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 7.76 d 8.49 d 84.5 a 84.1 a SEd 0.06 0.07 0.47 0.46 CD ( p ≤ 0.05) 0.13 0.16 0.97 0.95 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting The nDAP sprayed plants had maintained higher RWC regardless of growth stages or seasons. The nDAP sprayed rice plants (84.5; 84.4%) had consistently higher RWC than its counterpart cDAP (83.9; 83.8%) at AT during Rabi 2023 and Kharif 2024, respectively. Similar trend of results recorded at the PI stage. Pooled data have shown that nDAP sprayed plants had higher RWC than cDAP sprayed plants. 2.3. Biochemical Changes in Rice 2.3.1. Key enzymes involved in Nitrogen assimilation The N assimilation in plant system catalysed by a set of key enzymes namely nitrate reductase (NR), glutamine synthetase (GS) and glutamate oxy-glutarate amino transferase (GOGAT) measured at the active tillering (AT) and panicle Initiation (PI) is presented (Table 5 ). During Rabi 2023, the NR activities in nDAP sprayed plants (19.5 & 22.0 µg of NO 2 g − 1 hr − 1 ) that were consistently and significantly higher than cDAP sprayed plants (12.1 & 19.3 µg of NO 2 g − 1 hr − 1 ) at the AT and PI stages, respectively. Higher activities of NR in nDAP sprayed plants clearly indicate the influx of N in the system. Similar trend of response was observed regardless of critical stages of crop growth or seasons. Pooled data have shown that NR activity was higher in nDAP than cDAP sprayed plants regardless of stages of observation. Table 5 Nitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT) and acid phosphatase (APS) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately Treatments NR (µg of NO 2 g − 1 h − 1 ) GS (µmol g − 1 FW h − 1 ) GOGAT (µmol NADH g − 1 FW h − 1 ) APS (mM g − 1 h − 1 ) 1st spray 2nd spray 1st spray 2nd spray 1st spray 2nd spray 1st spray 2nd spray Rabi 2023 T1–0% RDP 05.2 d 07.5 d 101.2 c 134.5 c 152.4 c 193.2 c 480.1 d 512.3 d T2–100% RDP 21.4 a 22.5 a 284.1 a 290.1 a 187.5 a 224.8 a 584.5 b 625.4 b T3–75% RDP + 1% cDAP FS@25th and 45th DAT 12.1 c 19.3 c 148.7 b 185.4 b 177.2 b 210.1 b 536.6 c 604.1 c T4–75% RDP + 0.5% nDAP FS@25th and 45th DAT 19.5 b 22.0 b 282.6 a 288.9 a 186.3 a 225.0 a 784.7 a 788.1 a SEd 0.11 0.15 1.52 1.70 1.41 1.56 4.50 4.91 CD ( p ≤ 0.05) 0.25 0.33 3.31 3.71 3.08 3.62 9.81 10.69 Kharif 2024 T1–0% RDP 6.4 c 9.6 d 95.4 d 100.4 c 141.2 d 166.2 d 357.2 d 412.4 d T2–100% RDP 18.3 a 20.4 b 189.6 a 195.6 a 179.5 a 195.3 a 486.3 b 501.8 b T3–75% RDP + 1% DAP FS@25th and 45th DAT 14.7 b 18.5 c 120.7 c 135.1 b 164.8 c 178.7 c 410.7 c 459.3 c T4–75% RDP + 0.5% Nano DAP FS@25th and 45th DAT 17.9 a 21.2 a 182.9 b 192.7 b 176.6 b 190.0 b 501.2 a 520.4 a SEd 0.29 0.28 2.50 2.51 0.94 0.70 3.63 2.59 CD ( p ≤ 0.05) 0.63 0.62 5.46 5.47 2.05 1.52 7.92 5.65 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting The data on glutamine synthetase (GS) have shown that foliar spray of nDAP had significantly higher activities than cDAP at the AT and PI stages regardless of Rabi 2023 or Kharif 2024 but the values are comparable to 100% RDP (Table 5 ). GS catalyses incorporation of ammonium into amino acid glutamine. The GS activities measured in nDAP treatments were 282.6 and 288.9 µmol g − 1 FW h − 1 at AT and PI stages which were higher in cDAP by 47.4% and 35.8%, respectively. Pooled data indicated that the GS activities was higher in nDAP than cDAP sprayed plants at both AT and PI stages. The data are in conformity with the observations of Maloth et al. (2024) who have shown that two rounds of foliar sprays of Gromor® nDAP in rice had significantly increased the GS activities in rice when fertilized along with 100% NPK. The GOGAT assists in synthesis of glutamate from glutamine and keto-glutarate and this process plays a central role in N assimilation. The nDAP sprayed rice plants registered significantly higher GOGAT activities (186.3; 225 µmol NADH g − 1 FW h − 1 ) than cDAP sprayed plants (177; 210 µmol NADH g − 1 FW h − 1 ) at AT and PI stages, respectively, during Rabi 2023 (Table 5 ). But the values are comparable to the plants that received 100% RDP. Similar trend of response was observed during Kharif 2024. 2.3.2. Acid Phosphatase Activity During Kharif 2023, the nDAP sprayed plants had significantly higher ASP at AT (784.7 mM g h − 1 ) and PI (788.1 mM g h − 1 ) stages and the values are higher by 31.6% and 23.3%, respectively, in comparison to cDAP sprayed plants (Table 5 ). The same set of APS values were higher by 25.5% and 20.6% in comparison to 100% RDP. 2.3.3. Soluble Proteins The highest soluble protein contents were registered in treatment that received nDAP spray regardless of growth stages (AT 9.86; PI 9.55 mg g − 1 FW) during Rabi 2023. The increase in proteins in nDAP was 12.3% and 8.59% & 11.4% and 3.56%, respectively, in comparison to cDAP spay & 100% RDP at AT and PI stages (Table 6 ). During Kharif 2024, 100% RDP recorded significantly higher than nDAP spray treatment at AT but the later treatment had significantly higher values at PI. Table 6 Soluble proteins in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately Treatments Soluble Protein (mg g − 1 FW) Pooled Mean Rabi 2023 Kharif 2024 AT PI AT PI AT PI Absolute control 7.74 d 8.12 d 6.5 d 7.7 d 7.13 d 7.91 d 100% RDP 8.74 b 9.21 b 8.2 a 8.4 b 8.48 b 8.81 b 75% RDP + 1% cDAP FS@25th and 45th DAT 8.65 c 8.73 c 7.5 c 7.8 c 8.05 c 8.24 c 75% RDP + 0.5% nDAP FS@25th and 45th DAT 9.86 a 9.55 a 8.0 b 8.6 a 8.94 a 9.07 a SEd 0.069 0.70 0.04 0.03 0.05 0.06 CD ( p ≤ 0.05) 0.151 1.54 0.08 0.06 0.11 0.12 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting, ns-non significant 2.4. Nutrient content and uptake in rice The N and P contents in rice leaves registered the highest in nDAP sprayed plants but comparable to cDAP spray regardless of AT or PI and during both Rabi 2023 and Kharif 2024 seasons (Table 7 ) and significantly higher than 100% RDP and control. Pooled mean data also suggested the similar trend of response. Higher nutrient content in nDAP sprayed plants may be due to the effective N and P absorption and assimilation. Table 7 Nitrogen and phosphorous content (%) and uptake (kg ha − 1 ) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately Treatments N content (%) P content (%) N uptake (Kg/ha) P uptake (Kg/ha) AT PI AT PI AT PI AT PI Rabi 2024 T1–0% RDP 1.52 c 1.60b 0.44 c 0.55 c 15.0 d 20.7 d 4.46 d 7.0 d T2–100% RDP 1.67 b 1.70 b 0.45 c 0.61 b 26.5 c 33.7 c 7.26 c 9.1 c T3–75% RDP + 1% cDAP FS@25th and 45th DAT 1.74 b 1.94 a 0.56 b 0.63 ab 31.6 b 38.1 b 10.1 b 12.8 b T4–75% RDP + 0.5% nDAP FS@25th and 45th DAT 1.90 a 1.90 a 0.67 a 0.68 a 37.8 a 46.5 a 13.3 a 16.9 a SEd 0.05 0.06 0.03 0.02 1.39 1.60 0.47 0.57 CD ( p ≤ 0.05) 0.10 0.14 0.08 0.05 3.04 3.50 1.03 1.24 Kharif 2024 T1–0% RDP 1.37 b 1.46 b 0.40 d 0.50 a 12.8 d 18.5 d 4.12 d 6.2 d T2–100% RDP 2.08 a 2.21 a 0.53 b 0.61 b 25.0 c 30.8 c 6.84 c 8.6 c T3–75% RDP + 1% cDAP FS@25th and 45th DAT 1.98 a 2.0 a 0.62 a 0.66 ab 29.6 b 35.9 b 9.37 b 11.9 b T4–75% RDP + 0.5% nDAP FS@25th and 45th DAT 1.96 a 1.99 a 0.68 a 0.71 a 35.2 a 43.9 a 12.2 a 15.9 a SEd 0.08 0.10 0.03 0.04 0.99 1.20 0.31 0.33 CD ( p ≤ 0.05) 0.17 0.22 0.06 0.09 2.15 2.61 0.67 0.73 *Data refers mean of five replications , Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting The highest N and P uptake were registered in the treatment that received nDAP spray and are significantly higher than cDAP, 100% RDP and control (Table 7 ). Similar trend of response was observed at both AT and PI stages and seasons ( Rabi 2023 & Kharif 2024). The increase in N uptake in nDAP was 16.6 & 17.2%, 29.9 & 28.2% and 59.7 & 55.9% higher over cDAP, 100% RDP and control at AT and PI, stages, respectively, during Rabi 2023. Similar trend of response was observed in Kharif 2024. Pooled mean also exhibited a same pattern of response to the foliar spray of nDAP. The highest P uptake was registered in nDAP sprayed plants at AT (13.3) and PI (16.9 kg ha − 1 ) and the values were significantly higher than cDAP spray (AT 10.1; PI 12.8 kg ha − 1 ), 100% RDP (AT 7.26; PI 9.10 kg ha − 1 ) and control during Rabi 2023. Similar pattern of results observed in Kharif 2024 and from the polled mean. 3. Discussion The characteristics of the nano DAP (nDAP) is illustrated in Fig. 1. The basic characteristics of the nano DAP fully complied with the stipulated specifications (FCO, 2023). The conventional DAP (cDAP) is applied primarily in soil as a basal dose or topdressing during the crop growth period (Géant Basimine (2022). When the cDAP is broadcast in the soil, the cDAP gets dissolved in water and reach the plant roots by mass flow (Chuma et al., 2022; Islam et al., 2024) and diffusion (Chtouki et al., 2024; Weihrauch et al., 2018). Since, P is highly immobile in soil solution (Weihrauch et al., 2018) and its availability is enigmatic, the P use efficiency hardly exceeds 18–20% (Subramanian and Kumaraswamy, 1989; Subramanian et al., 2015; Kumar et al., 2024) and major portion of applied P gets into the water bodies causing eutrophication (Venukumar et al., 2024). In this context, the Gromor nDAP developed by Coromandel International Ltd is intended for foliar spray with higher use efficiency of both nitrogen and phosphorous. Recently, Yuvaraj et al. (2024) have reviewed the importance of nano-fertilizers and suggested that the foliar feeding of nano-fertilizers is more efficient in improving nutrient use efficiencies in comparison to soil-based nano-fertilizers. When nano fertilizers are sprayed, the encapsulated form nano-fertilizer enters the leaf through stomata and leaf pores as suggested by Shah et al. (2023) and translocated into the plant through apoplastic or symplastic movement (Kaneez et al., 2024). The process of translocation of nano-fertilizer in the plant system is elegantly illustrated Perez-de-Luque (2017). In our study, the absorption of nDAP in rice leaves was monitored hourly using high resolution imaging with SEM. The SEM images have clearly indicated that nDAP particles stayed on the leaf surface only for 2 hours and thereafter there was no remnants of nano-particles on the surface of the leaves (Fig. 2). On the other hand, cDAP sprayed leaves had the retention of the DAP particles on the surface of the leaves even after eight hours. It is widely believed that nano-particles are smaller in size that get absorbed rapidly. Our data are in agreement with the reports of Wang et al. (2023) who suggested various pathways in which nano-particles get absorbed and transported in plants that are closely associated with size, surface charge and chemical composition. The nano-sized particles < 5 nm is known to enter through hydrophilic or lipophilic channels (Yang et al., 2015; Banerjee et al., 2019). The SEM data clearly indicated that there is a rapid absorption nDAP in comparison to cDAP. Due to the quick absorption of nDAP, the rice plants had retained higher photosynthetic activities as illustrated in Fig. 3a (Miranda-Villagómez et al., 2019; Singh et al., 2021). Interestingly, the response to foliar spray of nDAP was more pronounced at the panicle initiation stage indicating the luxuriant consumption and utilization by rice plants. In another study, Singh et al. (2021) who have reported that the soil applied nDAP which was developed using cryo-milling has extremely small sized particles (5000 times smaller and 14000 times greater specific surface area) in comparison to cDAP. This assisted in enhanced growth of both wheat and tomato plants due to the increased bioavailability of inorganic P. This process facilitated higher physiological activities, growth and biomass production even with lesser amounts of input. As explained, nDAP sprayed plants had maintained significantly higher photosynthetic rates which is closely coincided with stomatal conductance (Fig. 3b). There is a well-established strong and positive correlation between the stomatal conductance and photosynthetic rate rates (Yin et al., 2020). Higher values of stomatal conductance indicate the greater amounts of CO 2 exchanges (Miranda-Villagómez et al., 2019; Singh et al., 2021). Further, the improved P nutrition assists in increased stomatal conductance which facilitates high photosynthetic activity even under drought-stressed conditions. It is well established that P requirement of crops reached at its peak at the flowering stage as P nutrition is utmost essential for sugar synthesis and further translocation of sugars and metabolites from the source (leaf) to sink (grain) (Al-Khuzai et al., 2020; Poudel et al., 2023). The data are in correspondence with the observations of Al-Khuai and Juthery (2020) who have shown comparative analysis of spraying of cDAP and nDAP in rice and depicted the unique advantage of miniaturization that facilitates easy absorption and assimilation of nutrients that lead to the reduction in lodging index and improve grains nutrient contents. All the gaseous exchange parameters are interconnected, and transpiration rate and stomatal conductance is strongly and positively correlated (Lv et al., 2024). Transpiration is an inevitable loss of moisture from leaves and the maintenance of higher values in the nDAP sprayed plants as an indicative of efficient photosynthetic rates which ultimately will reflect on the productivity of crops. Interestingly, the TR values in nDAP sprayed plants were higher than 100% RDP (Fig. 3c) suggesting that there is a saving of 25% RDP while ensuring the higher physiological activities of plants. On the other hand, Harrison et al. (2020) suggested that the interplay mechanisms between stomatal gaseous exchange and photosynthesis is complex, and that a disconnect often exists between the rates of CO 2 diffusion and photosynthetic carbon fixation. The relationship between the two parameters is highly dependent on environmental factors, such as light intensity, and could be exploited to improve crop performance. Overall, our data clearly demonstrate that all the gaseous exchange parameters such as photosynthetic rates, stomatal conductance and transpiration rate were significantly higher in nDAP sprayed than cDAP sprayed rice plants. nDAP sprayed plants are known to retain higher CO 2 utilization and transpiration rate that assisted in higher biomass production and utilization of nutrients (Bhuvaneshwari, 2024). The SPAD value is an indicative of N content of the leaves and foliar spray of nDAP or cDAP which carries associated nutrient N that assists in enhanced values, but the response is more pronounced in nDAP than cDAP. Kadhim et al. (2021) reported that the nano-fertilizers are efficient in absorption and permeability of into the plant tissues through the stomata holes, whose particle sizes are smaller than the diameter of the stomata and cell wall holes. In addition of the fertilizer recommendation and its effect on providing the plant with important nutrients, including nitrogen, which is important in amino acids and proteins formation, cell division and elongation. Our data agree with the observations of Jiang et al. (2017) who reported a close correlation between SPAD and chlorophyll content in tomato leaves. In our study, the chlorophyll concentrations measured at the PI stage was higher than AT regardless of seasons due to the progressive growth and completion of two rounds of sprays. Enhanced chlorophyll concentrations in nano-fertilizer sprayed plants have been reported in rice (Al-Khuzai et al., 2020), pearl millet (Shree et al., 2024), chickpea (Abisankar et al., 2024) and marigold (Sahithi et al., 2023). Overall, the data on SPAD, chlorophyll and anthocyanin clearly indicated that the nDAP sprayed plants retained higher values for chlorophyll index and chlorophyll concentration even with 75% RDP. Our data agree with the observations of reported literature (Al-Khuzai et al., 2020; Sahithi et al., 2023; Abisankar et al., 2024; Shree et al., 2024). Conversely, anthocyanin content in nDAP sprayed plants were lower indicating that these plants are nourished adequately and thus lower values than control or even 100% RDP. Recently, Bajji et al. (2002) have shown that electrolyte leakage technique can be used to assess the cell membrane stability as a mechanism of water stress tolerance in wheat. Since, nDAP sprayed plants are less stressed either by nutrients or water, these plants had the least values. Lower values of electrolyte leakage in nDAP sprayed plants clearly demonstrate that plants are adequately are nourished with nutrients and no indication of stress conditions. Membrane integrity of leaves and leaf RWC are important parameters to measure the turgidity of leaves. Nano-DAP sprayed leaves had maintained leaf turgidity that allow the plants to be photosynthetically more efficient in resource utilization and ultimately improved growth. Our data are in agreement with the observations of Abou-Sreea et al. (2022) who have shown positive impact of nano-P in maintaining turgidity of feugreek plants under water deficit conditions. In another study, foliar feeding of nano-P assists in improved plant performance of Phaseolus vulgaris under calcareous soil conditions (Rady Mustafa et al., 2020). To gain insights involved in the biochemical changes in nDAP sprayed plants, N assimilatory enzymes were assessed. The NR is the first enzyme in the nitrogen assimilatory pathway that is localized in cytosol converting nitrate to nitrite, which is further reduced to ammonium in plastids by nitrite reductase (Oaks, 1994). It is a substrate inducible enzyme, and its activity measures the availability of N for the metabolism and further reduction and assimilation into amino acids. Foliar spray of nDAP assists in quick absorption and the substrate readily available for the assimilation that eventually resulted in higher NR activities (Fig. 4a). Foliar spray of DAP is commonly used as practice as a supplementation of N and P at active growth stages to improve the nutrient status and productivity. Our data closely coincided with a review of Liu et al. (2022) who have reported that the N assimilation could be manipulated to improve the N use efficiency. In our case, nDAP sprays facilitated rapid absorption in comparison to cDAP as indicated by the SEM images may have helped to increase the NR activities. In the foliar spray treatments (nDAP & cDAP), 75% RDP fertilization was done with an intend to economize the fertilizers use and improve the use efficiency. In 100% RDP fertilization, the NR activities were significantly higher than the foliar sprays of DAP along with 75% RDP which may be attributed to the absorption of nutrients from the native soil including N. The NR being substrate inducible enzyme and the higher activities in nano-DAP sprayed plants clearly indicate the influx of N in the plant system. The GS activities in nDAP sprayed plants along with 75% RDP were comparable to 100% RDP of soil application (Fig. 4b). It is interesting to note that the nDAP sprays facilitated rapid assimilation of N in the plant system while economizing the fertilizer use by 25%. As GS is often referred as the regulatory factor that assists in governing N assimilation in the plant system (Rajesh et al., 2017) involving ATPs, it tends to indicate nano DAP assists in incorporation of N into amino acids. Our data align with the reports of Kaur et al., (2016) who have indicated the higher GS activities in rice coinciding with N content of rice leaves. Overall data on GOGAT suggested that the values significantly higher at AT and PI stages in nDAP than cDAP (Fig. 4c). Thus, nDAP spray facilitated the formation of glutamic acid catalysed by GOGAT. There is no reported literature available to relate nDAP spray in relation to GOGAT. Canas et al. (2020) have shown the leaf metabolic profiling of the different transgenic plants and indicated that the 2-Oxoglutarate synthesis is a key element acting at the interface of carbohydrate and amino acid metabolism. In this study, nDAP sprayed plants have registered higher photosynthetic activities which assists in the production of oxoglutarate that facilitates conversion of glutamine into glutamic acid catalysed by GOGAT. Overall, the N assimilatory enzymes suggest that nDAP has a unique advantage of rapid absorption and quick assimilation in the plant system. The acid phosphatase (APS) is the first enzyme in the phosphate assimilatory pathway, catalysing phosphate esters and it is one of the most important metabolic processes in the plant system. The APS secreted by plant roots is responsible for the solubilization of organic P into inorganic P that is taken up by plants for its metabolism. The APS in leaves indicate the P scavenging and remobilization processes. The DAP being the fertilizer prescribed as a source of P, acid phosphatase (ASP) activities in the nDAP and cDAP fertilized rice plants assessed (Fig. 4d). Higher values in nDAP sprayed plants are attributed to the rapid absorption by plant leaves. The pooled data have unequivocally demonstrated that APS is significantly higher in nDAP than cDAP regardless of stages. The data clearly demonstrated that when the plants are adequately nourished with P, the supplementary dose of nano-DAP has increased activities at the early stage of crop growth, but the increase get shrunk during the later stage of crop growth. On the other hand, when the maize plants are fertilized with 75% RDP, the APS activity increased by 2.5 times from the vegetative stage to the reproductive phase. It is quite interesting to note that the APS activities at the reproductive phase is higher in plants nourished with 75% RDP with nano-DAP sprays. As APS is responsible for remobilization of nutrients, it has direct and phenomenal relevance to promote the productivity of crops. Higher soluble proteins in nDAP sprayed rice plants may be attributed to the effective utilization of P. As explained, all the key enzymes involved in N and P assimilatory pathways have been shown enhanced activities that may have reflected on the total soluble proteins in the leaves. Since N and P nutrition is essential for protein synthesis, it can be inferred that higher protein content closely coincided with enzyme activities and photosynthetic rates in the nDAP sprayed plants. Our data agree with the reports of Khemshetty et al. (2024) who have shown that foliar feeding of nano DAP combined with soil application of 75% RDF registered 19.5% protein content in pigeon pea which on par with 100% RDF. In our study, we found that the nDAP sprayed had registered higher photosynthetic rate, stomatal conductance and transpiration rate that may have collectively contributed for the higher uptake and utilization of nutrients. Further, we also indicated higher activities of N and P assimilatory enzymes that may have facilitated protein and amino acid synthesis that eventually led to the higher nutrient content. Our data agree with the reports of Sahoo et al. (2024) who have indicated soil foliar application of nano DAP has increased the N and P contents in the rice grain and straw, but the values were comparable to soil application of 100% RDP. Similar observations were made in wheat by Poudel et al. (2023). Our data in combination with reported literature, it is quite evident that foliar spray nDAP has a unique advantage of rapid absorption and quick assimilation besides higher photosynthetic efficiency that assist in improved nutrient status in plants. Such processes can support to retain higher nutrient status even if the plants were nourished with 75% RDP. The higher uptake of N is attributed to the higher photosynthetic efficiency and N assimilation. Our data closely coincided with the observations of Sahoo et al. (2024) in rice and Poudel et al. (2023) in wheat. The higher P uptake in the treatment that received nDAP is due to the rapid absorption and assimilation of P. As explained, the nDAP sprayed plants had higher acid phosphatase activity indicating the incorporation of inorganic P into organic compounds. The data corresponding to the observations of Parmar et al. (2024) who have suggested that foliar spray of nano DAP has enhanced both N and P uptake in wheat. Overall, the data tend to indicate that foliar spray of nDAP improved the nutrient content and uptake in rice even if the plants were fertilized with 75% RDP. The data clearly demonstrated that foliar spray of nano DAP gets absorbed quickly, assimilated rapidly, assists in improved gaseous exchanges, facilitated N and P assimilation and retained higher nutrient uptake. Nano DAP spray is multi-functional and it supports physiological, biochemical and nutritional changes that collectively contributed for the better performance of crops. More detailed studies are to be undertaken to gain knowledge in the use of innovative nano-fertilizers in improving the productivity of crops. 4. MATERIALS AND METHODS Field experiments were conducted in Wetlands, Tamil Agricultural University, Coimbatore, Tamil Nadu, India (Latitude 11 o N; 76.9 o E), during Rabi 2023 (Oct. – Dec. 2023) and Agricultural Research Station, Bhavanisagar during Kharif 2024 (June – Sept. 2024) using rice as a test crop (variety Co. 55). The experimental soil in Coimbatore was clay loam texture, pH 8.2, low soil organic carbon (0.4%), low in available N (146 kg ha − 1 ), high in available P (24 kg ha − 1 ) and K (146 kg ha − 1 ). The experimental soil in Bhavanisagar was sandy loam texture, pH 6.9, low soil organic carbon (0.3%), medium in available N (296 kg ha − 1 ), high in available P (13 kg ha − 1 ) and K (458 kg ha − 1 ). Treatments consisted of 100% RDP, foliar spray of cDAP (twice), foliar spray of nDAP (twice) at active tillering and panicle initiation stages along control replicated five times in a randomized block design. The entire recommended dose of P @ 50 kg P 2 O 5 ha − 1 was applied as basal in the form diammonium phosphate. For the foliar spray treatments, 75% RDP was applied basally. The recommended doses of 150 kg N and 50 K 2 O kg ha − 1 were applied as urea and muriate of potash, respectively. Urea and muriate of potash were applied as basal 50% and the remaining 50% two equal splits at 20 and 40 days after transplanting. Gromor nano DAP (2% N; 5% P 2 O 5 ) obtained from Coromandel International Ltd, Hyderabad, was used for the study as per the recommendation (@ 500 ml nano DAP dissolved in 100 litres of water and sprayed over one acre of rice field). Other standard cultivation practices were adopted as per the TNAU Crop Production Guide 2021. The standard cultivation practices were adopted. 4.1. Characterization of Gromor Nano DAP The nano-DAP was characterized for the basic parameters such as pH, size, zeta potential, viscosity, nutrient concentrations (N & P) and specific gravity as per the standard operating protocols suggested in the FCO and verified whether it fulfils the stipulated specifications as per the notification (FCO, 2023). The nano-DAP specifications and analytical values obtained are furnished in Table 1 . 4.2. High Resolution Imaging using SEM to determine rapid absorption of nano DAP During the second field experiment, high resolution imaging was done using Scanning Electron Microscope (Techni 240, FEI, Netherlands) on the nDAP sprayed and cDAP sprayed rice plants. After the first spray at 20 DAT, fully opened leaves were excised and stored in liquid N 2 , sputtered and mounted on the stub to examine under the SEM. Leaf sampling was done in nano DAP and conventional DAP sprayed rice plants eight times on an hourly basis. This was done in Field Experiment I. All other physiological, biochemical and nutritional parameters were measured in both the field experiments. 4.3. Physiological Changes 4.3.1. Gas exchange measurements The gas exchange parameters such as photosynthetic rate, stomatal conductance and transpiration rate were measured in rice leaves of all the four treatments using a portable photosynthesis system (Model: CI-340, CID Bioscience, USA). The measurements were done in randomly selected 3 plants from each replication and the mean values are presented. The readings were recorded from 10.00 am to 12.00 noon on a clear sunny day, photosynthetically active radiation at 1500 µmol photons m − 2 s − 1 , and the CO 2 level at 410 ppm. A fully expanded third leaf from the top was used for measuring the gas exchange parameters. Water use efficiency (Instantaneous) was calculated as the ratio between photosynthesis and transpiration rate and expressed in µmol CO 2 m mol − 1 H 2 O (Warrier and Venkataramanan, 2010). 4.3.2. Chlorophyll Index The chlorophyll index was measured in three plants from each replication and three positions (top, middle and bottom), using a SPAD meter (Minolta SPAD-502, Japan) as described by Minolta (1989) and Monje and Bugbee (1992). 4.3.3. Chlorophyll content Fresh rice leaves sampled from the field were homogenised in 2 mL of 80% acetone using a pestle & mortar and centrifuged at 10,000 rpm for 5 min. The optical density of the supernatant was measured using a quartz cuvette and 80% acetone as a blank with a Beckman CoulterTM, Inc. (USA), DU®800 spectrophotometer at three wavelengths namely 663, 645 and 652 nm for chlorophyll a, b and total chlorophyll, respectively (Graan and Ort, 1984). Chlorophyll content was measured in both field experiments. Chlorophyll a (mg/g of FW) = (12.7 x OD at 663)-(2.69 x OD at 645) x \(\:\frac{\text{V}}{1000\:\text{x}\:\text{W}}\) Chlorophyll b (mg/g of FW) = (22.9 x OD at 645)-(4.68 x OD at 663) x \(\:\frac{\text{V}}{1000\:\text{x}\:\text{W}}\) Total chlorophyll (mg/g of FW) = \(\:\frac{\text{O}\text{D}\:\text{a}\text{t}\:652\:\times\:\text{V}}{34.5\:\times\:\text{W}}\) 4.3.4. Anthocyanin content Fresh leaves were pulverized, extracted with 5 mL of acidified ethanol (85:15 of 95% ethanol: 1.5 M HCl) for 1 h at room temperature, centrifuged at 10,000 rpm for 10 min, and the supernatant was collected and made up the volume to 25 mL and measured OD at 550 nm by using visible spectrophotometer and expressed as anthocyanin content in µg/g of FW (Sato et al., 1996). Anthocyanin content was calculated using the following equation: Anthocyanin= \(\:\frac{OD\:at\:550\:nm\:\times\:\:25\:\times\:1}{0.5\:\times\:1000\:\times\:98.2}\) 4.3.5. Membrane Integrity and electrolyte leachate The electrolyte leakage was determined using a methodology suggested by Zhang et al. (2013). Twenty-five leaf bits were transferred into 10 mL of deionized water, and the initial electrical conductivity was recorded as EC0. Then, the samples were subjected to 25 ◦ C for one hour, and electrical conductivity was noted as EC1. Finally, the samples were autoclaved at 100 ◦ C for 10 min., and the final electrical conductivity was measured as EC2. Membrane integrity was measured in both the experiments. The electrolyte leakage was computed using the following formula and expressed as a percentage Electrolyte leakage (%) = [(EC1 − EC0)/(EC2 − EC0)] × 100 4.3.6. Relative water content (RWC) The RWC was estimated by the formula given by Barrs and Weatherley (1962). Third fully opened leaf from the top of the plants was collected early in the morning. Leaf bits were soaked in water for 4 h and turgid weight was determined from these leaves. The samples were then kept in hot air oven at 60°C. The RWC was worked out after recording dry weight and expressed in per cent. 4.4. Biochemical analysis 4.4.1. Soluble Proteins Accurately 250 mg of rice leaf sample was macerated with 10 mL of phosphate buffer solution, centrifuged at 3000 rpm for 10 min. One mL of the supernatant solution was pipetted out into a 10 ml test tube and 5 mL of alkaline copper tartarate reagent was added and kept for 30 minutes for colour development. At the end of the reaction time, 0.5 mL of phenol reagent was added, and the OD value was measured at 660 nm. The protein content of the sample was expressed as mg g − 1 of leaf sample. 4.4.2. Nitrate Reductase (NR) The NR enzyme was estimated as per the protocol suggested by Hageman and Hucklesby (1971). Rice leaf tissue was cut into small pieces and placed in ice-cold incubation medium containing 3.0ml of 0.05M potassium phosphate buffer (pH 7.8) and 3.0ml of 0.4M KNO 3 solution. The tubes were placed in a desiccator and then incubated in water bath at 35ºC for 75 min under dark conditions. At the end of incubation period, tubes were kept in boiling water bath for 5min to stop the enzyme reaction and complete leaching of the nitrite in the medium. Nitrite was estimated by the method of Evans and Nason (1953). Aliquot from reaction mixture (0.2 ml) was taken and 1.0ml each of 1.0% sulphanilamide in 1N-HCl and 0.025% N-(1-Napthyl)-ethylene diammonium dichloride (NEDD) in double distilled water were added. The pink colour due to diazotisation was allowed to develop for 30 min after which the volume was made up to 6.0ml with double distilled water. The absorbance was read at 540 nm, using UV-VIS spectrophotometer. 4.4.3. Glutamine Synthetase (GS) Accurately, 200mg of leaf samples was ground in a chilled pestle and mortar with 5.0ml of grinding medium. The content was filtered through 4 layers of cheese cloth and centrifuged at 10000rpm for 20min (Subramanian and Charest, 1998). The supernatant solution was passed through a column of Shepherded G-25 (12 x 2.5cm) and glutamine synthetase and glutamate synthase were determined. The enzyme extract was allowed to react with the reaction mixture (0.75ml containing 50mM Tris-maleate buffer, pH7.5, 67mM hydroxylamine, 80mM l-glutamine, 8mM ATP, 4mM EDTA, 50µl of crude enzyme extract and 33mM Mg 2+ as MgCl 2 ). The blank was run with buffer (excluding glutamine). The reaction mixture was allowed to stand for 10min at 25˚C. The reaction was stopped by adding 0.2ml of a FeCl 3 mixture, centrifuged and absorbance measured at 540nm. Standard was run with y-glutamylhydroxmate (100–500µg range) and the enzyme reaction was stopped using ferric chloride reagent. 4.4.4. Glutamate Synthase (GOGAT) Accurately, 500mg of leaf samples was ground in a chilled pestle and mortar with 3 ml of grinding medium in the presence of polycar AT. The content was filtered through 4 layers of cheese cloth and centrifuged at 20000rpm for 30min. The enzyme extract was allowed to react with the reaction mixture (0.7ml of 0.1M Tris-HCI buffer (pH 7.5), 1ml of glutamine (pH 7.0), 0.1ml of 0.33M 2-oxoglutarte, 0.2ml of 10 − 3 M NADH and 1ml of enzyme extract. The blank was run with water 2-oxo glutarate. The reaction mixture was allowed to stand for 15–30 min at 37˚C. The change in absorbance was measured at 340nm. 4.4.5. Acid Phosphatase activity (APA) The APA was determined using the method described by Besford (1979). Fresh leaf tissue (0.25 g) was ground in a mortar in 10 ml of 50 mM citrate buffer (pH 5.8) for 4 min at 2°C. The homogenate was centrifuged at 10,000 rpm for 10 min and the supernatant assayed for acid phosphatase activity. The enzyme assay was based on the hydrolysis of p -nitrophenyl phosphate, the product of which, p -nitrophenol, can be estimated by visible spectrophotometry. The incubation mixture consisted of 20 µmol p-nitrophenyl phosphate, 50 µmol sodium acetate buffer, pH 5.8 and 0.5 ml of enzyme extract, all in a final volume of 2ml. The mixtures were incubated for 15 min at 30°C and the enzymic hydrolysis was stopped by the addition of 8 ml of 0.085 N NaOH. The absorbance of the solutions was then determined at 405 nm. 4.5. Nutritional attributes Leaf and root samples were collected, dried, extracted the nutrients using di acid (5:2 sulphuric acid and perchloric acid) and estimated for N and P contents as per standard protocols (Jackson, 1958; Piper, 1966). The nutrient concentrations were multiplied by biomass to derive the nutrient uptake. Nutrient uptake at the critical crop growth stages (active tillering and panicle initiation) was determined. 4.6. Statistical analysis The data collected from physiological, biochemical and nutritional parameters were analysed statistically using analysis of variance (ANOVA) and mean comparison test DMRT by SPSS software. 5. Conclusion This study is one of the pioneering attempts to gain insights of nano DAP using rice as a model plant system. The study encompasses physiological, biochemical and nutritional changes in the nano DAP and conventional DAP sprayed rice plants compared along with 100% RDP. High resolution imaging using SEM clearly demonstrated that the nDAP spray had a unique advantage of absorption within 2 hours while cDAP took more than 8 hours to get absorbed in rice plant system. Gaseous exchange parameters clearly indicated that nDAP sprayed plants had retained higher values suggesting the improved physiological activities. Further, these plants had higher SPAD and chlorophyll concentrations. Key enzyme activities involved in N and P assimilation were significantly higher in nDAP sprayed plants that clearly demonstrate the faster assimilation of foliar sprayed nutrients. Eventually, nDAP plants registered improved N and P contents and uptake indicating the role of nanotechnology in quick absorption, rapid assimilation and translocation of nutrients. Overall, this study has unequivocally demonstrated that foliar spray of nano DAP has an advantage of improved nutritional status of rice plants even with 75% of RDP while minimising the losses of nutrients. Declarations Author Contribution Author ContributionSR- Conducting field trials, data collection, report writing KSS- Conceptualization, writing the first draft, scientific interpretation, validation KM- Project monitoring UM- Data collection on physiological measurements, biochemical analysis, MJ- Field experiment, SEM analysis, Nutrient estimation, Uptake of nutrients PBK- Project funding, monitoring SG- Literature compilation, statistical analysis Acknowledgement The Authors of Tamil Nadu Agricultural University, Coimbatore, are thankful to the Coromandel International Limited, Hyderabad, for providing full financial support for the researchers, experimental expenses and analytical charges besides students fellowships Data Availability The dataset used and/or analysed during the current study available from the corresponding author on reasonable request References Abdel-Hakim, S. G., Shehata, A. S., Moghannem, S. A., Qadri, M., El-Ghany, M. F. A., Abdeldaym, E. A., & Darwish, O. S. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6238153","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":449744832,"identity":"4b0bf6f8-6486-49ce-b527-f25a52bd9fd7","order_by":0,"name":"Sharmila Rahale","email":"","orcid":"","institution":"Tamil Nadu agricultural University","correspondingAuthor":false,"prefix":"","firstName":"Sharmila","middleName":"","lastName":"Rahale","suffix":""},{"id":449744833,"identity":"1b10be7e-f1b9-4798-b594-2998362b1a68","order_by":1,"name":"K.S. Subramanian","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAr0lEQVRIiWNgGAWjYBACCQYGxgdwXgKRWpgNDpCqhU3iAEFlyECy//iz6o877BIb2A8/YHi4gwgt0hI5ZjcOnklObOBJM2BIPEOEFjkJHrYbB9uYExsYchgYEtuI0cJ//FnBwbb6xAb+N0RqkWZIMGM42HY4sUGCWFskZ+QYS5xtO27cJvHM4ABRWiTOH3/4obKtWrafP/nhw5/EaIEDNiA+QIqGUTAKRsEoGAV4AAAN7DSJZDl/4QAAAABJRU5ErkJggg==","orcid":"","institution":"Coromandel Nanotechnology Centre","correspondingAuthor":true,"prefix":"","firstName":"K.S.","middleName":"","lastName":"Subramanian","suffix":""},{"id":449744835,"identity":"c4dcddcd-15ed-424d-8ec1-0508be8c7af1","order_by":2,"name":"M Kalarani","email":"","orcid":"","institution":"Tamil Nadu agricultural University","correspondingAuthor":false,"prefix":"","firstName":"M","middleName":"","lastName":"Kalarani","suffix":""},{"id":449744836,"identity":"1cafa0d0-c2e7-4cb2-a073-7206f81c7f1e","order_by":3,"name":"M Umapathy","email":"","orcid":"","institution":"Tamil Nadu agricultural University","correspondingAuthor":false,"prefix":"","firstName":"M","middleName":"","lastName":"Umapathy","suffix":""},{"id":449744837,"identity":"8cadc8f4-2702-49d2-9016-180b8e34c903","order_by":4,"name":"J Mohanraj","email":"","orcid":"","institution":"Tamil Nadu agricultural University","correspondingAuthor":false,"prefix":"","firstName":"J","middleName":"","lastName":"Mohanraj","suffix":""},{"id":449744838,"identity":"d4ccdece-f1ee-419a-b460-a084910e3c92","order_by":5,"name":"B. K Parida","email":"","orcid":"","institution":"D Coromandel international limited","correspondingAuthor":false,"prefix":"","firstName":"B.","middleName":"K","lastName":"Parida","suffix":""},{"id":449744839,"identity":"e940551e-bbeb-412d-87d7-9c94f4e97c70","order_by":6,"name":"G Srinivasan","email":"","orcid":"","institution":"Coromandel Nanotechnology Centre","correspondingAuthor":false,"prefix":"","firstName":"G","middleName":"","lastName":"Srinivasan","suffix":""}],"badges":[],"createdAt":"2025-03-16 14:38:06","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6238153/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6238153/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":82139495,"identity":"799e4309-e434-4af5-865f-e9c50a406303","added_by":"auto","created_at":"2025-05-07 06:27:12","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":79843,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig1.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/f6092b643da00b26ad811d33.jpg"},{"id":82141650,"identity":"d01cdea5-095b-4f9d-be0b-1fe94e8e8fe9","added_by":"auto","created_at":"2025-05-07 06:35:12","extension":"jpg","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":75426,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig2.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/21ce8a1178a634fb660d7f02.jpg"},{"id":82139500,"identity":"7129cc6d-fa7a-4f93-ad2f-31eb3c0bb8b5","added_by":"auto","created_at":"2025-05-07 06:27:13","extension":"jpg","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":149434,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig3.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/0a8ab474091061142427dd73.jpg"},{"id":82141651,"identity":"6ed34e29-d494-4fe3-8f37-91e09b20673b","added_by":"auto","created_at":"2025-05-07 06:35:13","extension":"jpg","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":141651,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig4.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/0761b990f13b047a726a2031.jpg"},{"id":82139498,"identity":"f5ddd86f-7403-4228-8793-9234bd92497c","added_by":"auto","created_at":"2025-05-07 06:27:13","extension":"jpg","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":122798,"visible":true,"origin":"","legend":"\u003cp\u003eSee image above for figure legend\u003c/p\u003e","description":"","filename":"Fig5.jpg","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/003c7953c51ea0d900dba596.jpg"},{"id":91819746,"identity":"3cd271f3-8c47-484e-9ee7-448d16df492d","added_by":"auto","created_at":"2025-09-22 07:07:25","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2672135,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6238153/v1/291b012b-574e-4db4-a14d-d5da7b366872.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Foliar Feeding of Gromor Nano DAP on Physiological, Biochemical and Nutritional Changes in Rice","fulltext":[{"header":"1. INTRODUCTION","content":"\u003cp\u003ePhosphorous is one of the most critical essential nutrients required by crops which decides the crop productivity across the globe (Varshney et al., 2011). The P is highly immobile in soil and its availability is enigmatic due to the fixation (\u0026gt;\u0026thinsp;80%) in the soil as unavailable inorganic and organic forms (Timofeeva et al., 2022) besides runoff causing eutrophication in aquatic systems like lakes and rivers (Barathan et al., 2023). The radiotracer studies have precisely determined that the P use efficiencies in plants which hardly exceeds 18\u0026ndash;20% (Subramanian and Kumaraswamy, 1989) and the remaining major portion of unutilized forms of P stays in the ecosystem causing environmental hazard. Thus, there is a need for a new paradigm in plant nutrient management holistically ensuring circular economy approach to achieve a set of desirable goals to target socioeconomic, environmental and health objectives (Dobermann et al., 2022).\u003c/p\u003e \u003cp\u003ePhosphatic fertilizers are primarily manufactured from natural rock phosphates involving acidulation with concentrated sulfuric acids and the resultant products often associated with heavy metals and radioactive contaminants (Tayibi et al., 2009). The rock phosphates are natural reserve, non-renewable source and its deposits are fast depleting and a need for alternate route to develop P fertilizers. Further, import of phosphate rich rocks is facing a great deal of challenge as a recent development of war between Russia and Ukraine since 2022 that impeded the supply of raw materials for fertilizer production. India is dependent on imports nearly 5\u0026nbsp;million tonnes of phosphate rock, 2.5\u0026nbsp;million tonnes of phosphoric acid and 3\u0026nbsp;million tonnes of DAP annually during the year 2023\u0026ndash;2024 (Mint, 2024). In the case of diammonium phosphate, around 60% of the supply is imported. This necessitates to go in for an alternate form fertilizer which is sustainable. In India, 10.53\u0026nbsp;million tonnes of DAP were consumed during 2022\u0026ndash;2023 which was 13.5% higher than the previous years and the trend will continue to increase in the years to come (Annual Review of Fertilizer Production and Consumption 2022-23). To economize the P use and improve the P use efficiency is widely recommended for pulses (Krishna and Kaleeswari, 2018; Ashraf et al., 2024). However, it poses a practical difficulty of soaking overnight and the supernatant is filtered and sprayed on crops. To achieve balanced crop nutrition, DAP was more promoted by the Government of India than urea. One of the emerging areas appears to resolve the unresolved issues is nanotechnology which is widely being exploited in electronics, energy, environment, health sciences and agriculture (Ridhi et al., 2024).\u003c/p\u003e \u003cp\u003eNanotechnology is one of the fascinating fields of science which has a potential to manipulate atomic scale to develop processes and products involved in agricultural inputs that can be designed to minimize the losses and maximize the use efficiencies (Subramanian et al., 2015; El-Ramady et al., 2023). Considering the reviews and priority of India, major fertilizer companies like IFFCO and Coromandel International Limited were encouraged to produce nano-DAP to overcome the issue of imports and balanced crop nutrition (Business Standard, 2023) The Coromandel Gromor nano DAP was approved and notified (FCO, 2023). The nano phosphatic fertilizers developed using top down and bottom-up approaches have been evaluated in various crops such as rice (Saraiva et al., 2022), wheat (Poudel et al., 2023; Upadhyay et al., 2023), maize (Upadhyay et al., 2023), pearl millet (Upadhyay et al., 2023), mustard (Upadhyay et al., 2023), sunflower (Ernst et al., 2023) and tomato (Singh et al., 2021). Similarly, foliar spray of nano urea was tested in wheat (Kumar et al., 2023). Foliar spray of combined nano N and Nano-Zn has improved the yield and quality of fodder maize tested in northwestern plains of India. Abdel-Hakim et al. (2023) reported that the conjoint use of conventional fertilizers with nano-NPK fertilizers found to reduce the quantities of fertilizers by 75% or 50% of NPK requirements without significant adverse effects on the growth and productivity of lettuce cultivated in sandy soils. The literature review clearly indicated that the nano-fertilizers carrying single or multi-nutrients have the capability to improve the productivity of a wide array of crops while saving of fertilizers to the tune of 25\u0026ndash;50% of the recommended dose of fertilizers without associated environmental hazard.\u003c/p\u003e \u003cp\u003eThe literature review strongly set the stage to undertake the research on nano-DAP in rice production system. Saraiva et al. (2022) have shown that the delivery of P in the form of slow-release nano-P fertilizer instead of conventional bulk fertilizers reduced the amount of nutrients applied and increased the absorption by rice crop. Further, combining fertilizer effect with chitosan a natural polymer and biostimulant (Iftime et al., 2024) which commonly used as an encapsulant for the development of nano-fertilizers (Hamed et al., 2024) has an added benefit of plant protection against diseases and increase the resilience to stress (Hashim et al., 2024). In another study, Miranda-Villagomez et al. (2019) have demonstrated that nano-KH\u003csub\u003e2\u003c/sub\u003ePO\u003csub\u003e4\u003c/sub\u003e with trypsin promoted physiological efficiency for both roots and shoots of rice which consequently enhanced the plant biomass. Further, they established a close correlation between P accumulation in roots and shoots and P concentration. Poudel et al. (2023) reported that foliar feeding P in the form of nano-P combined with conventional DAP saved 25% of fertilizer P while reducing the P leaching into the groundwater and maintaining or increasing the wheat crop yield in the soils of North Gangetic Plains in India. Singh et al. (2021) have stated that the cryo-milled nano DAP has a particle size of 378 nm which is 5000 times smaller and specific surface area of 24.6 m\u003csup\u003e2\u003c/sup\u003e g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e which is 14,000 times greater than conventional DAP. Such an extensive surface area of nano-DAP facilitated the availability of P and enhanced the growth of wheat and tomato even with 75% of recommended dose of P for both the test crops. This assisted nano DAP fertilized plants to produce higher biomass production, longer shoots, shorter roots and less anthocyanin pigmentation even with 75% RDP in comparison to conventional DAP.\u003c/p\u003e \u003cp\u003eThe present study was conducted under field conditions to determine the physiological, biochemical and nutritional responses in rice plants fertilized with foliar spray of conventional DAP or nano-DAP (twice) in combination with 75% RDP, 100% RDP and control. In the both the set of field experiments, physiological (photosynthetic rate, stomatal conductance, transpiration rate, relative water content, membrane integrity), biochemical (nitrate reductase, glutamine synthetase, glutamate synthase, acid phosphatase, proteins, chlorophyll content, anthocyanin content) and nutritional (SPAD value, N \u0026amp; P contents, nutrient uptake) were measured at the active tillering and panicle initiation stages. Further, in the second set of experiment, high resolution imaging of nano DAP sprayed leaves was done to determine the absorption pattern in the rice leaves and complete key N assimilatory enzymes. The objective of the study is based on the hypothesis that nano-DAP sprays during the critical growth stages of rice crop orchestrates physiological, biochemical and nutritional changes that collectively contribute for the improved crop nutrition. These processes assist in economizing the P use through the foliar spray of nano DAP.\u003c/p\u003e"},{"header":"2. Results","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Characteristics of Nano DAP\u003c/h2\u003e \u003cp\u003eThe nDAP was analysed for its characteristics that fulfilled the stipulated specifications of FCO such as pH, hydrodynamic size (PSA), physical size (TEM), zeta potential, specific gravity, viscosity and nutrient concentrations. The nDAP particles were in the hydrodynamic and physical sizes in the range of 13.3\u0026ndash;33.5 nm and 43.7 nm, respectively. The nDAP had zeta potential (+\u0026thinsp;1.13 mV), acidic in pH (4.74), viscosity (8.86 cps), specific gravity (1.03 g cc\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), nitrogen (2.66%) and phosphorous (4.93% P\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e) (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSpecifications of Gromor nano DAP and actual values measured in the nano-DAP used in the experiments\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eNo.\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eParameters\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSpecifications\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eValues measured\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAppearance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003eOpalescent / light milky white solution\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003eLight milky white solution\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNitrogen concentration % min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u0026ndash;2%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.66\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eP\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e concentration % min\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3\u0026ndash;5%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.93\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003epH (liquid fertilizer sample measured directly)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4.5-6.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.74\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSpecific gravity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u0026ndash;1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.03\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eViscosity\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e5\u0026ndash;20 cps\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.86\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ePhysical Particle size (TEM)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10\u0026ndash;70 nm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e13.3\u0026ndash;30.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eHydrodynamic Particle Size (PSA)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;100 nm\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e43.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eSurface Charge /Zeta Potential (mV)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1\u0026ndash;5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.13\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2. Physiological Changes in Rice\u003c/h2\u003e \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e \u003ch2\u003e2.2.1. Photosynthetic Rate, Stomatal Conductance, Transpiration Rate and Water Use Efficiency\u003c/h2\u003e \u003cp\u003eThe photosynthetic rates of nDAP sprayed rice plants had significantly higher values after the active tillering (29.2) and panicle initiation (32.1 \u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) stages than cDAP (28.7; 30.5 \u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) sprayed treatment during \u003cem\u003eRabi\u003c/em\u003e 2023 (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). After the second spray, the percentage increase in photosynthetic rates in nDAP sprayed rice leaves were higher by 4.98, 4.04 and 42.7 in comparison to cDAP, 100% RDP and control, respectively. Similar trend of response was observed at the \u003cem\u003eKharif\u003c/em\u003e 2024 as well. The pooled analysis of data has clearly shown that nDAP sprayed plants registered higher photosynthetic rates regardless of growth stages than other treatments, but the response was more pronounced at the PI stage.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePhotosynthetic rate (\u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), stomatal conductance (mmol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), transpiration rate (mmol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and water use efficiency (\u0026micro;mol CO\u003csub\u003e2\u003c/sub\u003e mmol\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e H\u003csub\u003e2\u003c/sub\u003eO) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023) and Experiment II (Kharif 2024) separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003ePhotosynthetic rate\u003c/p\u003e \u003cp\u003e(\u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eStomatal conductance\u003c/p\u003e \u003cp\u003e(mmol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eTranspiration rate\u003c/p\u003e \u003cp\u003e(mmol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eWUE\u003c/p\u003e \u003cp\u003e(\u0026micro;mol CO\u003csub\u003e2\u003c/sub\u003e mmol\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e H\u003csub\u003e2\u003c/sub\u003eO)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRabi\u003c/b\u003e \u003cb\u003e2023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13.8\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e108.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e150.6\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.00\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.10\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.91\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.94\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e191.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e207.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.47\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.68\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.90\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.61\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e28.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e264.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e229.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.25\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.18\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.47\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.94\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e29.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e32.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e288.0\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e302.4a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e5.45\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e6.24\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e5.35\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.14\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.77\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.36\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e4.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.88\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKharif\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.8a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e286.2a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e319.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.8\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.0a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.9\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e24.6a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e29.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e362.0a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e387.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.6a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e7.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25.2a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e27.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e261.8a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e308.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.2b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.9\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e8.2a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e7.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e26.5a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e357.6a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e398.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e4.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.5a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.9\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.19\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e68.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.64\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e148.4\u003csup\u003ens\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.43\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e2.82\u003csup\u003ens\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe nDAP sprayed rice plants had significantly higher stomatal conductance at the active tillering (288) and panicle initiation (302 \u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) stages than cDAP (265; 230 mmol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) sprayed treatment during \u003cem\u003eRabi\u003c/em\u003e 2023 (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). After the two sprays, the nDAP sprayed plants had registered higher values by 24, 31.4 and 50% than the cDAP, 100% RDP and control, respectively.\u003c/p\u003e \u003cp\u003eTranspiration rate (TR) registered in treatments received foliar spray of cDAP and nDAP along with 75% RDP measured at the active tillering and panicle initiation stages are presented (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). During \u003cem\u003eRabi\u003c/em\u003e 2023, the treatment received 75% RDP along with foliar spray of nDAP recorded the highest transpiration rates of 5.45 and 6.24 mmol H\u003csub\u003e2\u003c/sub\u003eO m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e at the AT and PI stages, respectively. But the values in nDAP sprayed plants were significantly different at AT and comparable at PI with the cDAP sprayed plants. Similar trend of response was exhibited during \u003cem\u003eKharif\u003c/em\u003e 2024, but the values are smaller than \u003cem\u003eRabi\u003c/em\u003e 2024 irrespective of the treatments. Pooled data suggest that nDAP sprayed plants had higher TR regardless of stage, but the values are significantly higher at PI stage.\u003c/p\u003e \u003cp\u003eThe water use efficiency (WUE) as the measure of photosynthetic rates per unit of water utilized was recorded at AT and PI after the nDAP and cDAP sprayed rice plants during \u003cem\u003eRabi\u003c/em\u003e 2023 and \u003cem\u003eKharif\u003c/em\u003e 2024 seasons (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The data indicated that both nDAP and cDAP sprayed rice plants had significantly lower WUE than 100% RDP and control especially at the AT stage during \u003cem\u003eRabi\u003c/em\u003e 2023 and the data were not significant during \u003cem\u003eKharif\u003c/em\u003e 2024. However, at the PI stage, nDAP and cDAP sprayed plants had significantly higher WUE than 100% RDP. The pooled data indicated significantly lower values in nDAP than cDAP sprayed plants at AT and both were similar at PI stage.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003e2.2.2. SPAD value, total chlorophyll and anthocyanin content\u003c/h2\u003e \u003cp\u003eThe SPAD value, total chlorophyll and anthocyanin contents measured during active tillering (AT) and panicle initiation (PI) stages during \u003cem\u003eRabi\u003c/em\u003e 2023 and \u003cem\u003eKharif\u003c/em\u003e 2024 are presented in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. During \u003cem\u003eRabi\u003c/em\u003e 2023, SPAD values were significantly higher in nDAP (59.2; 59.5) than cDAP (45.4; 49.9) sprayed rice leaves at AT and PI stages, respectively. The percentage increase in SPAD values in 75% RDP\u0026thinsp;+\u0026thinsp;nDAP were 18.3 and 15.6 in comparison to 100% RDP at AT and PI, respectively. During \u003cem\u003eKharif\u003c/em\u003e 2024, such pronounced response was observed at the PI stage only. The pooled data also indicated an increase of 7\u0026ndash;9 units of SPAD values in comparison to cDAP sprayed plants and are significantly higher in nDAP than cDAP sprayed plants regardless of growth stages. In correspondence with the SPAD values, total chlorophyll concentrations in nDAP sprayed plants (0.65; 1.88) is significantly higher than cDAP (0.48; 1.61 mg/g FW) at AT and PI stages during Rabi 2023, but the values were lower than 100% RDP (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSPAD value, Chlorophyll (mg/g FW) and Anthocyanin concentrations (mg/g FM) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eSPAD value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eTotal Chlorophyll\u003c/p\u003e \u003cp\u003e(mg/g FW)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eAnthocyanin\u003c/p\u003e \u003cp\u003e(mg/g FW)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRabi\u003c/b\u003e \u003cb\u003e2023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.39\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.08\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.026\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.042\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e50.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.79\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.72\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.021\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.013\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e49.9\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.48\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.61\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.022\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.017\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e59.23\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e59.51\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.65\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.88\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.016\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.011\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.044\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0017\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.0018\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.82\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0038\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.0039\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKharif\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e40.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e43.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.34\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.15d\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.022\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.038\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e50.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.73\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.68b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.019\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.012\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45.2\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e47.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.51\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.36c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.020\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.018\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49.3\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.71\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.71\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.015\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.010\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e3.79\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.23\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.26\u003csup\u003ens\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePooled Mean\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45.0\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.36\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.11\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.024\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.040\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e49.6\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e51.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.76\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.70\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.020\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.013\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45.2\u003csup\u003ebc\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e48.6\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.49\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.48\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.021\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.017\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e54.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e55.8\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.68\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.79\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.015\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.010\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.007\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.0009\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.0014\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.0029\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe anthocyanin content of the nDAP and cDAP sprayed rice plants was measured and the data are presented in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. In contrast to the chlorophyll content, anthocyanin content in nDAP sprayed rice plants was significantly lower at AT and PI irrespective of the cropping season. Pooled data have revealed that anthocyanin content was significantly lower in nDAP than cDAP sprayed plants at both AT and PI stages.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.2.3. Electrolyte leakage and relative water content (RWC)\u003c/h2\u003e \u003cp\u003eThe electrolyte leakage was measured in nDAP and cDAP sprayed plants in order determine whether the plants are stressed (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e). The electrolyte leakage percentage lowest at AT and PI stages regardless of seasons. Indeed, the values are significantly lower in nDAP than cDAP in both the stages and seasons. The pooled data have clearly and consistently indicated that electrolyte leakage was significantly lower in nDAP than cDAP regardless of growth stages.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eElectrolyte leakage and relative water content (RWC) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eElectrolyte Leakage (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eRWC\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRabi\u003c/b\u003e \u003cb\u003e2023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.21\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.24\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e80.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e80.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.62\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.87\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.98\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.95\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e81.6\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e07.42\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.79\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.66\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.42\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKharif\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e10.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.8\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e82.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e83.8\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.5\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e85.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e84.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.1\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e85.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePooled Mean\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.85\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e10.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e81.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.0\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.01\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.18\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e83.8\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.59\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.72\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e83.3\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e82.9\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.76\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.49\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e84.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e84.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.46\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.95\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe nDAP sprayed plants had maintained higher RWC regardless of growth stages or seasons. The nDAP sprayed rice plants (84.5; 84.4%) had consistently higher RWC than its counterpart cDAP (83.9; 83.8%) at AT during \u003cem\u003eRabi\u003c/em\u003e 2023 and Kharif 2024, respectively. Similar trend of results recorded at the PI stage. Pooled data have shown that nDAP sprayed plants had higher RWC than cDAP sprayed plants.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e2.3. Biochemical Changes in Rice\u003c/h2\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003e2.3.1. Key enzymes involved in Nitrogen assimilation\u003c/h2\u003e \u003cp\u003eThe N assimilation in plant system catalysed by a set of key enzymes namely nitrate reductase (NR), glutamine synthetase (GS) and glutamate oxy-glutarate amino transferase (GOGAT) measured at the active tillering (AT) and panicle Initiation (PI) is presented (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). During Rabi 2023, the NR activities in nDAP sprayed plants (19.5 \u0026amp; 22.0 \u0026micro;g of NO\u003csub\u003e2\u003c/sub\u003e g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e hr\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) that were consistently and significantly higher than cDAP sprayed plants (12.1 \u0026amp; 19.3 \u0026micro;g of NO\u003csub\u003e2\u003c/sub\u003e g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e hr\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) at the AT and PI stages, respectively. Higher activities of NR in nDAP sprayed plants clearly indicate the influx of N in the system. Similar trend of response was observed regardless of critical stages of crop growth or seasons. Pooled data have shown that NR activity was higher in nDAP than cDAP sprayed plants regardless of stages of observation.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eNitrate reductase (NR), glutamine synthetase (GS), glutamate synthase (GOGAT) and acid phosphatase (APS) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eNR\u003c/p\u003e \u003cp\u003e(\u0026micro;g of NO\u003csub\u003e2\u003c/sub\u003e g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eh\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eGS\u003c/p\u003e \u003cp\u003e(\u0026micro;mol g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eGOGAT\u003c/p\u003e \u003cp\u003e(\u0026micro;mol NADH g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eAPS\u003c/p\u003e \u003cp\u003e(mM g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eh\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1st spray\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2nd spray\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRabi\u003c/b\u003e \u003cb\u003e2023\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e05.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e07.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e101.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e134.5\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e152.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e193.2\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e480.1\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e512.3\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e21.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e284.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e290.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e187.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e224.8\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e584.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e625.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% cDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e19.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e148.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e185.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e177.2\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e210.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e536.6\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e604.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% nDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e19.5\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.0\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e282.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e288.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e186.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e225.0\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e784.7\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e788.1\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e4.91\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e3.71\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.81\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e10.69\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKharif\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.6\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95.4\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e100.4\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e141.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e166.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e357.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e412.4\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e18.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e20.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e189.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e195.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e179.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e195.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e486.3\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e501.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e14.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e18.5\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e120.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e135.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e164.8\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e178.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e410.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e459.3\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% Nano DAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e17.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e21.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e182.9\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e192.7\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e176.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e190.0\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e501.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e520.4\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.28\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2.51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e3.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e2.59\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.63\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e5.46\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e5.65\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe data on glutamine synthetase (GS) have shown that foliar spray of nDAP had significantly higher activities than cDAP at the AT and PI stages regardless of Rabi 2023 or Kharif 2024 but the values are comparable to 100% RDP (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). GS catalyses incorporation of ammonium into amino acid glutamine. The GS activities measured in nDAP treatments were 282.6 and 288.9 \u0026micro;mol g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e at AT and PI stages which were higher in cDAP by 47.4% and 35.8%, respectively. Pooled data indicated that the GS activities was higher in nDAP than cDAP sprayed plants at both AT and PI stages. The data are in conformity with the observations of Maloth et al. (2024) who have shown that two rounds of foliar sprays of Gromor\u0026reg; nDAP in rice had significantly increased the GS activities in rice when fertilized along with 100% NPK.\u003c/p\u003e \u003cp\u003eThe GOGAT assists in synthesis of glutamate from glutamine and keto-glutarate and this process plays a central role in N assimilation. The nDAP sprayed rice plants registered significantly higher GOGAT activities (186.3; 225 \u0026micro;mol NADH g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) than cDAP sprayed plants (177; 210 \u0026micro;mol NADH g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) at AT and PI stages, respectively, during Rabi 2023 (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). But the values are comparable to the plants that received 100% RDP. Similar trend of response was observed during Kharif 2024.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section3\"\u003e \u003ch2\u003e2.3.2. Acid Phosphatase Activity\u003c/h2\u003e \u003cp\u003eDuring Kharif 2023, the nDAP sprayed plants had significantly higher ASP at AT (784.7 mM g h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and PI (788.1 mM g h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) stages and the values are higher by 31.6% and 23.3%, respectively, in comparison to cDAP sprayed plants (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). The same set of APS values were higher by 25.5% and 20.6% in comparison to 100% RDP.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section3\"\u003e \u003ch2\u003e2.3.3. Soluble Proteins\u003c/h2\u003e \u003cp\u003eThe highest soluble protein contents were registered in treatment that received nDAP spray regardless of growth stages (AT 9.86; PI 9.55 mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW) during \u003cem\u003eRabi\u003c/em\u003e 2023. The increase in proteins in nDAP was 12.3% and 8.59% \u0026amp; 11.4% and 3.56%, respectively, in comparison to cDAP spay \u0026amp; 100% RDP at AT and PI stages (Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e). During Kharif 2024, 100% RDP recorded significantly higher than nDAP spray treatment at AT but the later treatment had significantly higher values at PI.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eSoluble proteins in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"7\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003eSoluble Protein (mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c7\" namest=\"c6\" rowspan=\"2\"\u003e \u003cp\u003ePooled Mean\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cem\u003eRabi\u003c/em\u003e 2023\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003e\u003cem\u003eKharif\u003c/em\u003e 2024\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAbsolute control\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.74\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.12\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e6.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.7\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.13\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e7.91\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.74\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.21\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.4\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.48\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8.81\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e75% RDP\u0026thinsp;+\u0026thinsp;1% cDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e8.65\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8.73\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e7.5\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7.8\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.05\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8.24\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e75% RDP\u0026thinsp;+\u0026thinsp;0.5% nDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9.86\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9.55\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8.0\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e8.6\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.94\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e9.07\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.069\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.151\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.12\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"7\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting, ns-non significant\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e2.4. Nutrient content and uptake in rice\u003c/h2\u003e \u003cp\u003eThe N and P contents in rice leaves registered the highest in nDAP sprayed plants but comparable to cDAP spray regardless of AT or PI and during both \u003cem\u003eRabi\u003c/em\u003e 2023 and Kharif 2024 seasons (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e) and significantly higher than 100% RDP and control. Pooled mean data also suggested the similar trend of response. Higher nutrient content in nDAP sprayed plants may be due to the effective N and P absorption and assimilation.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eNitrogen and phosphorous content (%) and uptake (kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) in rice measured at active tillering (AT) and panicle initiation (PI) stages that coincided with 5 days after first and second conventional DAP (cDAP) or nano-DAP sprays (nDAP), respectively, along with 100% RDP and control. The standard error of difference (SEd) and critical difference (CD) are given to indicate the statistical difference as per ANOVA among the treatments. The ANOVA and mean comparison (DMRT) tests were performed for the Experiment I (Rabi 2023), Experiment II (Kharif 2024) and the pooled mean separately\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"9\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003eN content\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c5\" namest=\"c4\"\u003e \u003cp\u003eP content\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c7\" namest=\"c6\"\u003e \u003cp\u003eN uptake (Kg/ha)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003eP uptake (Kg/ha)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eAT\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePI\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eRabi\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.52\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.60b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.44\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.55\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e15.0\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e20.7\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.46\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e7.0\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.67\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.70\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.45\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.61\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e26.5\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e33.7\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e7.26\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e9.1\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% cDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.74\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.94\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.56\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.63\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e31.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e38.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.1\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e12.8\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% nDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.90\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.90\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.67\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.68\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e37.8\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e46.5\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.3\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e16.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.57\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.05\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e3.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e1.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1.24\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c9\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eKharif\u003c/b\u003e \u003cb\u003e2024\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT1\u0026ndash;0% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.37\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.46\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.40\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.50\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e12.8\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e18.5\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4.12\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6.2\u003csup\u003ed\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT2\u0026ndash;100% RDP\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.08\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.21\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.53\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.61\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25.0\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e30.8\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e6.84\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e8.6\u003csup\u003ec\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT3\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;1% cDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.98\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.0\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.62\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.66\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e29.6\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e35.9\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.37\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e11.9\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT4\u0026ndash;75% RDP\u0026thinsp;+\u0026thinsp;0.5% nDAP FS@25th and 45th DAT\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.96\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1.99\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.68\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.71\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e35.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e43.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e12.2\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e15.9\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSEd\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.03\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.04\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e1.20\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.31\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.33\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eCD (\u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026le;\u0026thinsp;0.05)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.17\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.09\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e2.15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e2.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.73\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"9\"\u003e\u003cem\u003e*Data refers mean of five replications\u003c/em\u003e, Treatments with same letters are not significantly different, FS: Foliar spray; DAT: Days after transplanting\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eThe highest N and P uptake were registered in the treatment that received nDAP spray and are significantly higher than cDAP, 100% RDP and control (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e). Similar trend of response was observed at both AT and PI stages and seasons (\u003cem\u003eRabi\u003c/em\u003e 2023 \u0026amp; \u003cem\u003eKharif\u003c/em\u003e 2024). The increase in N uptake in nDAP was 16.6 \u0026amp; 17.2%, 29.9 \u0026amp; 28.2% and 59.7 \u0026amp; 55.9% higher over cDAP, 100% RDP and control at AT and PI, stages, respectively, during Rabi 2023. Similar trend of response was observed in Kharif 2024. Pooled mean also exhibited a same pattern of response to the foliar spray of nDAP.\u003c/p\u003e \u003cp\u003eThe highest P uptake was registered in nDAP sprayed plants at AT (13.3) and PI (16.9 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and the values were significantly higher than cDAP spray (AT 10.1; PI 12.8 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), 100% RDP (AT 7.26; PI 9.10 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and control during Rabi 2023. Similar pattern of results observed in Kharif 2024 and from the polled mean.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Discussion","content":"\u003cp\u003eThe characteristics of the nano DAP (nDAP) is illustrated in Fig.\u0026nbsp;1. The basic characteristics of the nano DAP fully complied with the stipulated specifications (FCO, 2023). The conventional DAP (cDAP) is applied primarily in soil as a basal dose or topdressing during the crop growth period (G\u0026eacute;ant Basimine (2022). When the cDAP is broadcast in the soil, the cDAP gets dissolved in water and reach the plant roots by mass flow (Chuma et al., 2022; Islam et al., 2024) and diffusion (Chtouki et al., 2024; Weihrauch et al., 2018). Since, P is highly immobile in soil solution (Weihrauch et al., 2018) and its availability is enigmatic, the P use efficiency hardly exceeds 18\u0026ndash;20% (Subramanian and Kumaraswamy, 1989; Subramanian et al., 2015; Kumar et al., 2024) and major portion of applied P gets into the water bodies causing eutrophication (Venukumar et al., 2024).\u003c/p\u003e \u003cp\u003eIn this context, the Gromor nDAP developed by Coromandel International Ltd is intended for foliar spray with higher use efficiency of both nitrogen and phosphorous. Recently, Yuvaraj et al. (2024) have reviewed the importance of nano-fertilizers and suggested that the foliar feeding of nano-fertilizers is more efficient in improving nutrient use efficiencies in comparison to soil-based nano-fertilizers. When nano fertilizers are sprayed, the encapsulated form nano-fertilizer enters the leaf through stomata and leaf pores as suggested by Shah et al. (2023) and translocated into the plant through apoplastic or symplastic movement (Kaneez et al., 2024). The process of translocation of nano-fertilizer in the plant system is elegantly illustrated Perez-de-Luque (2017).\u003c/p\u003e \u003cp\u003eIn our study, the absorption of nDAP in rice leaves was monitored hourly using high resolution imaging with SEM. The SEM images have clearly indicated that nDAP particles stayed on the leaf surface only for 2 hours and thereafter there was no remnants of nano-particles on the surface of the leaves (Fig.\u0026nbsp;2). On the other hand, cDAP sprayed leaves had the retention of the DAP particles on the surface of the leaves even after eight hours. It is widely believed that nano-particles are smaller in size that get absorbed rapidly. Our data are in agreement with the reports of Wang et al. (2023) who suggested various pathways in which nano-particles get absorbed and transported in plants that are closely associated with size, surface charge and chemical composition. The nano-sized particles\u0026thinsp;\u0026lt;\u0026thinsp;5 nm is known to enter through hydrophilic or lipophilic channels (Yang et al., 2015; Banerjee et al., 2019). The SEM data clearly indicated that there is a rapid absorption nDAP in comparison to cDAP.\u003c/p\u003e \u003cp\u003eDue to the quick absorption of nDAP, the rice plants had retained higher photosynthetic activities as illustrated in Fig.\u0026nbsp;3a (Miranda-Villag\u0026oacute;mez et al., 2019; Singh et al., 2021). Interestingly, the response to foliar spray of nDAP was more pronounced at the panicle initiation stage indicating the luxuriant consumption and utilization by rice plants. In another study, Singh et al. (2021) who have reported that the soil applied nDAP which was developed using cryo-milling has extremely small sized particles (5000 times smaller and 14000 times greater specific surface area) in comparison to cDAP. This assisted in enhanced growth of both wheat and tomato plants due to the increased bioavailability of inorganic P. This process facilitated higher physiological activities, growth and biomass production even with lesser amounts of input.\u003c/p\u003e \u003cp\u003eAs explained, nDAP sprayed plants had maintained significantly higher photosynthetic rates which is closely coincided with stomatal conductance (Fig.\u0026nbsp;3b). There is a well-established strong and positive correlation between the stomatal conductance and photosynthetic rate rates (Yin et al., 2020). Higher values of stomatal conductance indicate the greater amounts of CO\u003csub\u003e2\u003c/sub\u003e exchanges (Miranda-Villag\u0026oacute;mez et al., 2019; Singh et al., 2021). Further, the improved P nutrition assists in increased stomatal conductance which facilitates high photosynthetic activity even under drought-stressed conditions. It is well established that P requirement of crops reached at its peak at the flowering stage as P nutrition is utmost essential for sugar synthesis and further translocation of sugars and metabolites from the source (leaf) to sink (grain) (Al-Khuzai et al., 2020; Poudel et al., 2023). The data are in correspondence with the observations of Al-Khuai and Juthery (2020) who have shown comparative analysis of spraying of cDAP and nDAP in rice and depicted the unique advantage of miniaturization that facilitates easy absorption and assimilation of nutrients that lead to the reduction in lodging index and improve grains nutrient contents.\u003c/p\u003e \u003cp\u003eAll the gaseous exchange parameters are interconnected, and transpiration rate and stomatal conductance is strongly and positively correlated (Lv et al., 2024). Transpiration is an inevitable loss of moisture from leaves and the maintenance of higher values in the nDAP sprayed plants as an indicative of efficient photosynthetic rates which ultimately will reflect on the productivity of crops. Interestingly, the TR values in nDAP sprayed plants were higher than 100% RDP (Fig.\u0026nbsp;3c) suggesting that there is a saving of 25% RDP while ensuring the higher physiological activities of plants. On the other hand, Harrison et al. (2020) suggested that the interplay mechanisms between stomatal gaseous exchange and photosynthesis is complex, and that a disconnect often exists between the rates of CO\u003csub\u003e2\u003c/sub\u003e diffusion and photosynthetic carbon fixation. The relationship between the two parameters is highly dependent on environmental factors, such as light intensity, and could be exploited to improve crop performance. Overall, our data clearly demonstrate that all the gaseous exchange parameters such as photosynthetic rates, stomatal conductance and transpiration rate were significantly higher in nDAP sprayed than cDAP sprayed rice plants. nDAP sprayed plants are known to retain higher CO\u003csub\u003e2\u003c/sub\u003e utilization and transpiration rate that assisted in higher biomass production and utilization of nutrients (Bhuvaneshwari, 2024).\u003c/p\u003e \u003cp\u003eThe SPAD value is an indicative of N content of the leaves and foliar spray of nDAP or cDAP which carries associated nutrient N that assists in enhanced values, but the response is more pronounced in nDAP than cDAP. Kadhim et al. (2021) reported that the nano-fertilizers are efficient in absorption and permeability of into the plant tissues through the stomata holes, whose particle sizes are smaller than the diameter of the stomata and cell wall holes. In addition of the fertilizer recommendation and its effect on providing the plant with important nutrients, including nitrogen, which is important in amino acids and proteins formation, cell division and elongation. Our data agree with the observations of Jiang et al. (2017) who reported a close correlation between SPAD and chlorophyll content in tomato leaves. In our study, the chlorophyll concentrations measured at the PI stage was higher than AT regardless of seasons due to the progressive growth and completion of two rounds of sprays. Enhanced chlorophyll concentrations in nano-fertilizer sprayed plants have been reported in rice (Al-Khuzai et al., 2020), pearl millet (Shree et al., 2024), chickpea (Abisankar et al., 2024) and marigold (Sahithi et al., 2023). Overall, the data on SPAD, chlorophyll and anthocyanin clearly indicated that the nDAP sprayed plants retained higher values for chlorophyll index and chlorophyll concentration even with 75% RDP. Our data agree with the observations of reported literature (Al-Khuzai et al., 2020; Sahithi et al., 2023; Abisankar et al., 2024; Shree et al., 2024). Conversely, anthocyanin content in nDAP sprayed plants were lower indicating that these plants are nourished adequately and thus lower values than control or even 100% RDP.\u003c/p\u003e \u003cp\u003eRecently, Bajji et al. (2002) have shown that electrolyte leakage technique can be used to assess the cell membrane stability as a mechanism of water stress tolerance in wheat. Since, nDAP sprayed plants are less stressed either by nutrients or water, these plants had the least values. Lower values of electrolyte leakage in nDAP sprayed plants clearly demonstrate that plants are adequately are nourished with nutrients and no indication of stress conditions. Membrane integrity of leaves and leaf RWC are important parameters to measure the turgidity of leaves. Nano-DAP sprayed leaves had maintained leaf turgidity that allow the plants to be photosynthetically more efficient in resource utilization and ultimately improved growth. Our data are in agreement with the observations of Abou-Sreea et al. (2022) who have shown positive impact of nano-P in maintaining turgidity of feugreek plants under water deficit conditions. In another study, foliar feeding of nano-P assists in improved plant performance of \u003cem\u003ePhaseolus vulgaris\u003c/em\u003e under calcareous soil conditions (Rady Mustafa et al., 2020).\u003c/p\u003e \u003cp\u003eTo gain insights involved in the biochemical changes in nDAP sprayed plants, N assimilatory enzymes were assessed. The NR is the first enzyme in the nitrogen assimilatory pathway that is localized in cytosol converting nitrate to nitrite, which is further reduced to ammonium in plastids by nitrite reductase (Oaks, 1994). It is a substrate inducible enzyme, and its activity measures the availability of N for the metabolism and further reduction and assimilation into amino acids. Foliar spray of nDAP assists in quick absorption and the substrate readily available for the assimilation that eventually resulted in higher NR activities (Fig.\u0026nbsp;4a). Foliar spray of DAP is commonly used as practice as a supplementation of N and P at active growth stages to improve the nutrient status and productivity. Our data closely coincided with a review of Liu et al. (2022) who have reported that the N assimilation could be manipulated to improve the N use efficiency. In our case, nDAP sprays facilitated rapid absorption in comparison to cDAP as indicated by the SEM images may have helped to increase the NR activities. In the foliar spray treatments (nDAP \u0026amp; cDAP), 75% RDP fertilization was done with an intend to economize the fertilizers use and improve the use efficiency. In 100% RDP fertilization, the NR activities were significantly higher than the foliar sprays of DAP along with 75% RDP which may be attributed to the absorption of nutrients from the native soil including N. The NR being substrate inducible enzyme and the higher activities in nano-DAP sprayed plants clearly indicate the influx of N in the plant system.\u003c/p\u003e \u003cp\u003eThe GS activities in nDAP sprayed plants along with 75% RDP were comparable to 100% RDP of soil application (Fig.\u0026nbsp;4b). It is interesting to note that the nDAP sprays facilitated rapid assimilation of N in the plant system while economizing the fertilizer use by 25%. As GS is often referred as the regulatory factor that assists in governing N assimilation in the plant system (Rajesh et al., 2017) involving ATPs, it tends to indicate nano DAP assists in incorporation of N into amino acids. Our data align with the reports of Kaur et al., (2016) who have indicated the higher GS activities in rice coinciding with N content of rice leaves.\u003c/p\u003e \u003cp\u003eOverall data on GOGAT suggested that the values significantly higher at AT and PI stages in nDAP than cDAP (Fig.\u0026nbsp;4c). Thus, nDAP spray facilitated the formation of glutamic acid catalysed by GOGAT. There is no reported literature available to relate nDAP spray in relation to GOGAT. Canas et al. (2020) have shown the leaf metabolic profiling of the different transgenic plants and indicated that the 2-Oxoglutarate synthesis is a key element acting at the interface of carbohydrate and amino acid metabolism. In this study, nDAP sprayed plants have registered higher photosynthetic activities which assists in the production of oxoglutarate that facilitates conversion of glutamine into glutamic acid catalysed by GOGAT. Overall, the N assimilatory enzymes suggest that nDAP has a unique advantage of rapid absorption and quick assimilation in the plant system.\u003c/p\u003e \u003cp\u003eThe acid phosphatase (APS) is the first enzyme in the phosphate assimilatory pathway, catalysing phosphate esters and it is one of the most important metabolic processes in the plant system. The APS secreted by plant roots is responsible for the solubilization of organic P into inorganic P that is taken up by plants for its metabolism. The APS in leaves indicate the P scavenging and remobilization processes. The DAP being the fertilizer prescribed as a source of P, acid phosphatase (ASP) activities in the nDAP and cDAP fertilized rice plants assessed (Fig.\u0026nbsp;4d). Higher values in nDAP sprayed plants are attributed to the rapid absorption by plant leaves. The pooled data have unequivocally demonstrated that APS is significantly higher in nDAP than cDAP regardless of stages. The data clearly demonstrated that when the plants are adequately nourished with P, the supplementary dose of nano-DAP has increased activities at the early stage of crop growth, but the increase get shrunk during the later stage of crop growth. On the other hand, when the maize plants are fertilized with 75% RDP, the APS activity increased by 2.5 times from the vegetative stage to the reproductive phase. It is quite interesting to note that the APS activities at the reproductive phase is higher in plants nourished with 75% RDP with nano-DAP sprays. As APS is responsible for remobilization of nutrients, it has direct and phenomenal relevance to promote the productivity of crops.\u003c/p\u003e \u003cp\u003eHigher soluble proteins in nDAP sprayed rice plants may be attributed to the effective utilization of P. As explained, all the key enzymes involved in N and P assimilatory pathways have been shown enhanced activities that may have reflected on the total soluble proteins in the leaves. Since N and P nutrition is essential for protein synthesis, it can be inferred that higher protein content closely coincided with enzyme activities and photosynthetic rates in the nDAP sprayed plants. Our data agree with the reports of Khemshetty et al. (2024) who have shown that foliar feeding of nano DAP combined with soil application of 75% RDF registered 19.5% protein content in pigeon pea which on par with 100% RDF.\u003c/p\u003e \u003cp\u003eIn our study, we found that the nDAP sprayed had registered higher photosynthetic rate, stomatal conductance and transpiration rate that may have collectively contributed for the higher uptake and utilization of nutrients. Further, we also indicated higher activities of N and P assimilatory enzymes that may have facilitated protein and amino acid synthesis that eventually led to the higher nutrient content. Our data agree with the reports of Sahoo et al. (2024) who have indicated soil foliar application of nano DAP has increased the N and P contents in the rice grain and straw, but the values were comparable to soil application of 100% RDP. Similar observations were made in wheat by Poudel et al. (2023). Our data in combination with reported literature, it is quite evident that foliar spray nDAP has a unique advantage of rapid absorption and quick assimilation besides higher photosynthetic efficiency that assist in improved nutrient status in plants. Such processes can support to retain higher nutrient status even if the plants were nourished with 75% RDP. The higher uptake of N is attributed to the higher photosynthetic efficiency and N assimilation. Our data closely coincided with the observations of Sahoo et al. (2024) in rice and Poudel et al. (2023) in wheat.\u003c/p\u003e \u003cp\u003eThe higher P uptake in the treatment that received nDAP is due to the rapid absorption and assimilation of P. As explained, the nDAP sprayed plants had higher acid phosphatase activity indicating the incorporation of inorganic P into organic compounds. The data corresponding to the observations of Parmar et al. (2024) who have suggested that foliar spray of nano DAP has enhanced both N and P uptake in wheat. Overall, the data tend to indicate that foliar spray of nDAP improved the nutrient content and uptake in rice even if the plants were fertilized with 75% RDP.\u003c/p\u003e \u003cp\u003eThe data clearly demonstrated that foliar spray of nano DAP gets absorbed quickly, assimilated rapidly, assists in improved gaseous exchanges, facilitated N and P assimilation and retained higher nutrient uptake. Nano DAP spray is multi-functional and it supports physiological, biochemical and nutritional changes that collectively contributed for the better performance of crops. More detailed studies are to be undertaken to gain knowledge in the use of innovative nano-fertilizers in improving the productivity of crops.\u003c/p\u003e"},{"header":"4. MATERIALS AND METHODS","content":"\u003cp\u003eField experiments were conducted in Wetlands, Tamil Agricultural University, Coimbatore, Tamil Nadu, India (Latitude 11\u003csup\u003eo\u003c/sup\u003eN; 76.9\u003csup\u003eo\u003c/sup\u003eE), during \u003cem\u003eRabi\u003c/em\u003e 2023 (Oct. \u0026ndash; Dec. 2023) and Agricultural Research Station, Bhavanisagar during \u003cem\u003eKharif\u003c/em\u003e 2024 (June \u0026ndash; Sept. 2024) using rice as a test crop (variety Co. 55). The experimental soil in Coimbatore was clay loam texture, pH 8.2, low soil organic carbon (0.4%), low in available N (146 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), high in available P (24 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and K (146 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e). The experimental soil in Bhavanisagar was sandy loam texture, pH 6.9, low soil organic carbon (0.3%), medium in available N (296 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), high in available P (13 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and K (458 kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e). Treatments consisted of 100% RDP, foliar spray of cDAP (twice), foliar spray of nDAP (twice) at active tillering and panicle initiation stages along control replicated five times in a randomized block design.\u003c/p\u003e \u003cp\u003eThe entire recommended dose of P @ 50 kg P\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e was applied as basal in the form diammonium phosphate. For the foliar spray treatments, 75% RDP was applied basally. The recommended doses of 150 kg N and 50 K\u003csub\u003e2\u003c/sub\u003eO kg ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e were applied as urea and muriate of potash, respectively. Urea and muriate of potash were applied as basal 50% and the remaining 50% two equal splits at 20 and 40 days after transplanting. Gromor nano DAP (2% N; 5% P\u003csub\u003e2\u003c/sub\u003eO\u003csub\u003e5\u003c/sub\u003e) obtained from Coromandel International Ltd, Hyderabad, was used for the study as per the recommendation (@ 500 ml nano DAP dissolved in 100 litres of water and sprayed over one acre of rice field). Other standard cultivation practices were adopted as per the TNAU Crop Production Guide 2021. The standard cultivation practices were adopted.\u003c/p\u003e \u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e4.1. Characterization of Gromor Nano DAP\u003c/h2\u003e \u003cp\u003eThe nano-DAP was characterized for the basic parameters such as pH, size, zeta potential, viscosity, nutrient concentrations (N \u0026amp; P) and specific gravity as per the standard operating protocols suggested in the FCO and verified whether it fulfils the stipulated specifications as per the notification (FCO, 2023). The nano-DAP specifications and analytical values obtained are furnished in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e4.2. High Resolution Imaging using SEM to determine rapid absorption of nano DAP\u003c/h2\u003e \u003cp\u003eDuring the second field experiment, high resolution imaging was done using Scanning Electron Microscope (Techni 240, FEI, Netherlands) on the nDAP sprayed and cDAP sprayed rice plants. After the first spray at 20 DAT, fully opened leaves were excised and stored in liquid N\u003csub\u003e2\u003c/sub\u003e, sputtered and mounted on the stub to examine under the SEM. Leaf sampling was done in nano DAP and conventional DAP sprayed rice plants eight times on an hourly basis. This was done in Field Experiment I. All other physiological, biochemical and nutritional parameters were measured in both the field experiments.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e4.3. Physiological Changes\u003c/h2\u003e \u003cdiv id=\"Sec18\" class=\"Section3\"\u003e \u003ch2\u003e4.3.1. Gas exchange measurements\u003c/h2\u003e \u003cp\u003eThe gas exchange parameters such as photosynthetic rate, stomatal conductance and transpiration rate were measured in rice leaves of all the four treatments using a portable photosynthesis system (Model: CI-340, CID Bioscience, USA). The measurements were done in randomly selected 3 plants from each replication and the mean values are presented. The readings were recorded from 10.00 am to 12.00 noon on a clear sunny day, photosynthetically active radiation at 1500 \u0026micro;mol photons m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and the CO\u003csub\u003e2\u003c/sub\u003e level at 410 ppm. A fully expanded third leaf from the top was used for measuring the gas exchange parameters. Water use efficiency (Instantaneous) was calculated as the ratio between photosynthesis and transpiration rate and expressed in \u0026micro;mol CO\u003csub\u003e2\u003c/sub\u003e m mol\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e H\u003csub\u003e2\u003c/sub\u003eO (Warrier and Venkataramanan, 2010).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec19\" class=\"Section3\"\u003e \u003ch2\u003e4.3.2. Chlorophyll Index\u003c/h2\u003e \u003cp\u003eThe chlorophyll index was measured in three plants from each replication and three positions (top, middle and bottom), using a SPAD meter (Minolta SPAD-502, Japan) as described by Minolta (1989) and Monje and Bugbee (1992).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec20\" class=\"Section3\"\u003e \u003ch2\u003e4.3.3. Chlorophyll content\u003c/h2\u003e \u003cp\u003eFresh rice leaves sampled from the field were homogenised in 2 mL of 80% acetone using a pestle \u0026amp; mortar and centrifuged at 10,000 rpm for 5 min. The optical density of the supernatant was measured using a quartz cuvette and 80% acetone as a blank with a Beckman CoulterTM, Inc. (USA), DU\u0026reg;800 spectrophotometer at three wavelengths namely 663, 645 and 652 nm for chlorophyll a, b and total chlorophyll, respectively (Graan and Ort, 1984). Chlorophyll content was measured in both field experiments.\u003c/p\u003e \u003cp\u003eChlorophyll a (mg/g of FW) = (12.7 x OD at 663)-(2.69 x OD at 645) x \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\frac{\\text{V}}{1000\\:\\text{x}\\:\\text{W}}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003cp\u003eChlorophyll b (mg/g of FW) = (22.9 x OD at 645)-(4.68 x OD at 663) x \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\frac{\\text{V}}{1000\\:\\text{x}\\:\\text{W}}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003cp\u003eTotal chlorophyll (mg/g of FW) = \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\frac{\\text{O}\\text{D}\\:\\text{a}\\text{t}\\:652\\:\\times\\:\\text{V}}{34.5\\:\\times\\:\\text{W}}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec21\" class=\"Section3\"\u003e \u003ch2\u003e4.3.4. Anthocyanin content\u003c/h2\u003e \u003cp\u003eFresh leaves were pulverized, extracted with 5 mL of acidified ethanol (85:15 of 95% ethanol: 1.5 M HCl) for 1 h at room temperature, centrifuged at 10,000 rpm for 10 min, and the supernatant was collected and made up the volume to 25 mL and measured OD at 550 nm by using visible spectrophotometer and expressed as anthocyanin content in \u0026micro;g/g of FW (Sato et al., 1996).\u003c/p\u003e \u003cp\u003eAnthocyanin content was calculated using the following equation:\u003c/p\u003e \u003cp\u003eAnthocyanin= \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\frac{OD\\:at\\:550\\:nm\\:\\times\\:\\:25\\:\\times\\:1}{0.5\\:\\times\\:1000\\:\\times\\:98.2}\\)\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec22\" class=\"Section3\"\u003e \u003ch2\u003e4.3.5. Membrane Integrity and electrolyte leachate\u003c/h2\u003e \u003cp\u003eThe electrolyte leakage was determined using a methodology suggested by Zhang et al. (2013). Twenty-five leaf bits were transferred into 10 mL of deionized water, and the initial electrical conductivity was recorded as EC0. Then, the samples were subjected to 25 \u003csup\u003e◦\u003c/sup\u003eC for one hour, and electrical conductivity was noted as EC1. Finally, the samples were autoclaved at 100 \u003csup\u003e◦\u003c/sup\u003eC for 10 min., and the final electrical conductivity was measured as EC2. Membrane integrity was measured in both the experiments. The electrolyte leakage was computed using the following formula and expressed as a percentage\u003c/p\u003e \u003cp\u003eElectrolyte leakage (%) = [(EC1\u0026thinsp;\u0026minus;\u0026thinsp;EC0)/(EC2\u0026thinsp;\u0026minus;\u0026thinsp;EC0)] \u0026times; 100\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec23\" class=\"Section3\"\u003e \u003ch2\u003e4.3.6. Relative water content (RWC)\u003c/h2\u003e \u003cp\u003eThe RWC was estimated by the formula given by Barrs and Weatherley (1962). Third fully opened leaf from the top of the plants was collected early in the morning. Leaf bits were soaked in water for 4 h and turgid weight was determined from these leaves. The samples were then kept in hot air oven at 60\u0026deg;C. The RWC was worked out after recording dry weight and expressed in per cent.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec24\" class=\"Section2\"\u003e \u003ch2\u003e4.4. Biochemical analysis\u003c/h2\u003e \u003cdiv id=\"Sec25\" class=\"Section3\"\u003e \u003ch2\u003e4.4.1. Soluble Proteins\u003c/h2\u003e \u003cp\u003eAccurately 250 mg of rice leaf sample was macerated with 10 mL of phosphate buffer solution, centrifuged at 3000 rpm for 10 min. One mL of the supernatant solution was pipetted out into a 10 ml test tube and 5 mL of alkaline copper tartarate reagent was added and kept for 30 minutes for colour development. At the end of the reaction time, 0.5 mL of phenol reagent was added, and the OD value was measured at 660 nm. The protein content of the sample was expressed as mg g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e of leaf sample.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec26\" class=\"Section3\"\u003e \u003ch2\u003e4.4.2. Nitrate Reductase (NR)\u003c/h2\u003e \u003cp\u003eThe NR enzyme was estimated as per the protocol suggested by Hageman and Hucklesby (1971). Rice leaf tissue was cut into small pieces and placed in ice-cold incubation medium containing 3.0ml of 0.05M potassium phosphate buffer (pH 7.8) and 3.0ml of 0.4M KNO\u003csub\u003e3\u003c/sub\u003e solution. The tubes were placed in a desiccator and then incubated in water bath at 35\u0026ordm;C for 75 min under dark conditions. At the end of incubation period, tubes were kept in boiling water bath for 5min to stop the enzyme reaction and complete leaching of the nitrite in the medium. Nitrite was estimated by the method of Evans and Nason (1953). Aliquot from reaction mixture (0.2 ml) was taken and 1.0ml each of 1.0% sulphanilamide in 1N-HCl and 0.025% N-(1-Napthyl)-ethylene diammonium dichloride (NEDD) in double distilled water were added. The pink colour due to diazotisation was allowed to develop for 30 min after which the volume was made up to 6.0ml with double distilled water. The absorbance was read at 540 nm, using UV-VIS spectrophotometer.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec27\" class=\"Section3\"\u003e \u003ch2\u003e4.4.3. Glutamine Synthetase (GS)\u003c/h2\u003e \u003cp\u003eAccurately, 200mg of leaf samples was ground in a chilled pestle and mortar with 5.0ml of grinding medium. The content was filtered through 4 layers of cheese cloth and centrifuged at 10000rpm for 20min (Subramanian and Charest, 1998). The supernatant solution was passed through a column of Shepherded G-25 (12 x 2.5cm) and glutamine synthetase and glutamate synthase were determined. The enzyme extract was allowed to react with the reaction mixture (0.75ml containing 50mM Tris-maleate buffer, pH7.5, 67mM hydroxylamine, 80mM l-glutamine, 8mM ATP, 4mM EDTA, 50\u0026micro;l of crude enzyme extract and 33mM Mg\u003csup\u003e2+\u003c/sup\u003e as MgCl\u003csub\u003e2\u003c/sub\u003e). The blank was run with buffer (excluding glutamine). The reaction mixture was allowed to stand for 10min at 25˚C. The reaction was stopped by adding 0.2ml of a FeCl\u003csub\u003e3\u003c/sub\u003e mixture, centrifuged and absorbance measured at 540nm. Standard was run with y-glutamylhydroxmate (100\u0026ndash;500\u0026micro;g range) and the enzyme reaction was stopped using ferric chloride reagent.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec28\" class=\"Section3\"\u003e \u003ch2\u003e4.4.4. Glutamate Synthase (GOGAT)\u003c/h2\u003e \u003cp\u003eAccurately, 500mg of leaf samples was ground in a chilled pestle and mortar with 3 ml of grinding medium in the presence of polycar AT. The content was filtered through 4 layers of cheese cloth and centrifuged at 20000rpm for 30min. The enzyme extract was allowed to react with the reaction mixture (0.7ml of 0.1M Tris-HCI buffer (pH 7.5), 1ml of glutamine (pH 7.0), 0.1ml of 0.33M 2-oxoglutarte, 0.2ml of 10\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003eM NADH and 1ml of enzyme extract. The blank was run with water 2-oxo glutarate. The reaction mixture was allowed to stand for 15\u0026ndash;30 min at 37˚C. The change in absorbance was measured at 340nm.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec29\" class=\"Section3\"\u003e \u003ch2\u003e4.4.5. Acid Phosphatase activity (APA)\u003c/h2\u003e \u003cp\u003eThe APA was determined using the method described by Besford (1979). Fresh leaf tissue (0.25 g) was ground in a mortar in 10 ml of 50 mM citrate buffer (pH 5.8) for 4 min at 2\u0026deg;C. The homogenate was centrifuged at 10,000 rpm for 10 min and the supernatant assayed for acid phosphatase activity. The enzyme assay was based on the hydrolysis of \u003cem\u003ep\u003c/em\u003e-nitrophenyl phosphate, the product of which, \u003cem\u003ep\u003c/em\u003e-nitrophenol, can be estimated by visible spectrophotometry. The incubation mixture consisted of 20 \u0026micro;mol p-nitrophenyl phosphate, 50 \u0026micro;mol sodium acetate buffer, pH 5.8 and 0.5 ml of enzyme extract, all in a final volume of 2ml. The mixtures were incubated for 15 min at 30\u0026deg;C and the enzymic hydrolysis was stopped by the addition of 8 ml of 0.085 N NaOH. The absorbance of the solutions was then determined at 405 nm.\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec30\" class=\"Section2\"\u003e \u003ch2\u003e4.5. Nutritional attributes\u003c/h2\u003e \u003cp\u003eLeaf and root samples were collected, dried, extracted the nutrients using di acid (5:2 sulphuric acid and perchloric acid) and estimated for N and P contents as per standard protocols (Jackson, 1958; Piper, 1966). The nutrient concentrations were multiplied by biomass to derive the nutrient uptake. Nutrient uptake at the critical crop growth stages (active tillering and panicle initiation) was determined.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec31\" class=\"Section2\"\u003e \u003ch2\u003e4.6. Statistical analysis\u003c/h2\u003e \u003cp\u003eThe data collected from physiological, biochemical and nutritional parameters were analysed statistically using analysis of variance (ANOVA) and mean comparison test DMRT by SPSS software.\u003c/p\u003e \u003c/div\u003e"},{"header":"5. Conclusion","content":"\u003cp\u003eThis study is one of the pioneering attempts to gain insights of nano DAP using rice as a model plant system. The study encompasses physiological, biochemical and nutritional changes in the nano DAP and conventional DAP sprayed rice plants compared along with 100% RDP. High resolution imaging using SEM clearly demonstrated that the nDAP spray had a unique advantage of absorption within 2 hours while cDAP took more than 8 hours to get absorbed in rice plant system. Gaseous exchange parameters clearly indicated that nDAP sprayed plants had retained higher values suggesting the improved physiological activities. Further, these plants had higher SPAD and chlorophyll concentrations. Key enzyme activities involved in N and P assimilation were significantly higher in nDAP sprayed plants that clearly demonstrate the faster assimilation of foliar sprayed nutrients. Eventually, nDAP plants registered improved N and P contents and uptake indicating the role of nanotechnology in quick absorption, rapid assimilation and translocation of nutrients. Overall, this study has unequivocally demonstrated that foliar spray of nano DAP has an advantage of improved nutritional status of rice plants even with 75% of RDP while minimising the losses of nutrients.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAuthor ContributionSR- Conducting field trials, data collection, report writing KSS- Conceptualization, writing the first draft, scientific interpretation, validation KM- Project monitoring UM- Data collection on physiological measurements, biochemical analysis, MJ- Field experiment, SEM analysis, Nutrient estimation, Uptake of nutrients PBK- Project funding, monitoring SG- Literature compilation, statistical analysis\u003c/p\u003e\u003ch2\u003eAcknowledgement\u003c/h2\u003e\u003cp\u003eThe Authors of Tamil Nadu Agricultural University, Coimbatore, are thankful to the Coromandel International Limited, Hyderabad, for providing full financial support for the researchers, experimental expenses and analytical charges besides students fellowships\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eThe dataset used and/or analysed during the current study available from the corresponding author on reasonable request\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbdel-Hakim, S. 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Subramanian, and EmanTawfik Hussien. \u0026quot;Slow release nanofertilizer for sustainable agriculture.\u0026quot; In \u003cem\u003eNanofertilizer Delivery, Effects and Application Methods\u003c/em\u003e, pp. 53-69 (2024).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"nano DAP, physiological, biochemical, nutritional responses, rice","lastPublishedDoi":"10.21203/rs.3.rs-6238153/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6238153/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eField experiments were conducted during two crop seasons (\u003cem\u003eRabi\u003c/em\u003e 2023 and \u003cem\u003eKharif\u003c/em\u003e 2024) to determine physiological, biochemical and nutritional responses of rice to the foliar spray of nano DAP (nDAP) in comparison to conventional DAP. The data on SEM images showed that nDAP gets absorbed by leaves rapidly within 2 hours in comparison to cDAP (\u0026gt;\u0026thinsp;12 hrs). Combined application of 75% RDP with two rounds of nDAP at critical stages had significantly higher photosynthetic rates (3.4\u0026ndash;7.7%), stomatal conductance (18\u0026ndash;23%), transpiration rate (6\u0026ndash;7%) and SPAD (12.9\u0026ndash;16.6%) than cDAP spray. Nitrogen assimilatory enzymes NR (nDAP 21.6; cDAP 18.9 \u0026micro;g NO\u003csub\u003e2\u003c/sub\u003e g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eh\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), GS (nDAP 240.8; 160.2 \u0026micro;mol g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), GOGAT (nDAP 207.5; cDAP 194.4 \u0026micro;mol NADH g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e FW h\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) and ASP (nDAP 654.2; cDAP 531.7 \u0026micro;mol g\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003eh\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) activities were higher in nDAP than cDAP sprayed plants. Nano DAP sprayed rice plants had higher N and P contents in critical growth stages. Data showed that nDAP gets absorbed in the plant system rapidly and orchestrate the physiological processes and nitrogen and phosphorous assimilatory pathways that collectively contributed for the improved N and P contents. This one of the early reports suggesting insights involved in nDAP sprayed plants leading to nutrient status.\u003c/p\u003e","manuscriptTitle":"Foliar Feeding of Gromor Nano DAP on Physiological, Biochemical and Nutritional Changes in Rice","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-05-07 06:27:08","doi":"10.21203/rs.3.rs-6238153/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"9aef77c6-8a6d-4ad4-8ac5-7185e0ed62db","owner":[],"postedDate":"May 7th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":47857801,"name":"Biological sciences/Plant sciences/Plant physiology"},{"id":47857802,"name":"Earth and environmental sciences/Environmental sciences"}],"tags":[],"updatedAt":"2025-09-22T07:05:28+00:00","versionOfRecord":[],"versionCreatedAt":"2025-05-07 06:27:08","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-6238153","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6238153","identity":"rs-6238153","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}