Identifying Limiting Nutrients for Wheat Production in Halaba, Central Ethiopia

Identifying Limiting Nutrients for Wheat Production in Halaba, Central Ethiopia | 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 Identifying Limiting Nutrients for Wheat Production in Halaba, Central Ethiopia Abay Ayalew, Moges Tadese This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8012941/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 15 You are reading this latest preprint version Abstract Low wheat yields in Ethiopia are largely attributed to nutrient imbalances and blanket fertilizer use without site-specific recommendations. A field experiment was conducted across eight sites in Wera Dijo District, Halaba Zone, Central Ethiopia, during the 2021 cropping season to identify the most limiting nutrients for wheat ( Triticum aestivum L.) using nutrient omission trials. The study employed a randomized complete block design with ten treatments, omitting one nutrient at a time alongside complete, NP, and control treatments. Pre-treatment soil analyses showed slightly acidic to neutral pH (6.06–6.99), medium to high organic carbon (1.85–4.19%), and low to medium phosphorus (3.10–10.94 mg/kg). Phosphorus deficiency was observed at seven of the eight sites. Nutrient treatments had a highly significant (p < 0.0001) effect on yield and yield components. Omission of nitrogen and phosphorus markedly reduced yield, with nitrogen omission causing the greatest loss, indicating N as the most limiting nutrient. In contrast, omission of K, S, Zn, and B had no significant effect. Comparable yields from NP and complete treatments highlight the adequacy of site-specific N and P fertilization. These results emphasize the need for localized nutrient management to enhance wheat productivity and fertilizer efficiency in Halaba and similar agro-ecologies. Biological sciences/Ecology Earth and environmental sciences/Ecology Earth and environmental sciences/Environmental sciences Biological sciences/Plant sciences Nutrient omission Macro- and micronutrients Fertilizer recommendation Yield penalty Figures Figure 1 Figure 2 Figure 3 1. Introduction Wheat ( Triticum aestivum L.) is a vital staple crop, feeding about one-third of the worldwide population, delivering half of nutritional protein, and more than half of calories. It is cultivated on around 218 million hectares worldwide, with an average yield of 3.3 t/ha (Giraldo et al., 2019). In Ethiopia, wheat ranks fourth in terms of area cultivated—after tef ( Eragrostis tef Zucc.), maize ( Zea mays L.), and sorghum ( Sorghum bicolor L. Moench)—but is second only to maize in terms of consumption (Solomon and Anjulo, 2017; CSA, 2007; Hodson et al., 2020). Despite the crop’s significance and extensive cultivation, Ethiopia’s national average wheat yield remains low, at just 2.2 t/ha—significantly below its potential yield of 8.3 t/ha (Senbeta and Worku, 2023). This yield gap is largely attributed to factors such as soil fertility depletion due to intensive nutrient mining, and the continued use of blanket fertilizer recommendations that fail to account for local soil nutrient variability (MoARD, 2008). One of the challenges in Ethiopia is the widespread use of ‘blanket’ recommendations– whereby a single fertilizer rate is prescribed for a large area or across the entire country (Abera et al., 2022). Farmers in Halaba area apply blanket fertilizer recommendation for wheat production. Such generalized fertilizer application limits productivity and leads to inefficient nutrient uptake (IFA, WFO, & GACSA, 2016) calling for the development of site-specific nutrient management option. Site-Specific Nutrient Management (SSNM) optimizes nutrient supply in space and time to meet crop requirements, thereby enhancing productivity and fertilizer use efficiency (Richards, 2015). The nutrient omission technique, a key approach in SSNM, provides a systematic framework to assess the soil’s inherent nutrient-supplying capacity and guide site-specific fertilizer application (Getinet et al., 2024). Recent research highlights that, while nitrogen (N), phosphorus (P), and potassium (K) are commonly deficient, secondary and micronutrients such as sulfur (S), zinc (Zn), and boron (B) are increasingly recognized as limiting factors for crop growth globally (Tamene et al., 2017; IFA et al., 2016). Nutrient omission trials across Ethiopia have confirmed that deficiencies in N, P, K, S, Zn, and B can significantly limit crop productivity depending on the agro-ecological context (Fageria et al., 2011). For instance, a study in Wondo District, Oromia Region, demonstrated that application of blended fertilizers containing N, P, S, and B significantly improved key wheat growth parameters, including plant height, spike length, fertile tiller count, straw yield, and grain yield (Jewaro et al., 2020). Similarly, another study in South Wollo, Amhara Region, reported significant yield improvements with nitrogen fertilizer application alone (Tehulie, 2021). In areas like Halaba in the Central Ethiopia Region, where detailed nutrient diagnostics are limited, identifying specific nutrient constraints is critical to improving wheat yields and promoting efficient, sustainable fertilizer use. While nitrogen and phosphorus have received substantial attention, the roles of K, S, Zn, and B in this region remain underexplored. Therefore, the objective of this study was to identify the most limiting nutrient(s) for wheat production in Halaba through field-based nutrient omission trials. The main hypothesis is that one or more nutrients in the soils of the study area limit wheat production. The results will support the development of site-specific nutrient management strategies, contributing to increased wheat productivity, improved fertilizer efficiency, and more sustainable agricultural practices in the region. 2. Materials and Methods 2.1 Description of the Study Area The experiment was conducted during the 2021 cropping season at eight locations within the Wera Dijo District, Halaba Zone, Central Ethiopia (Fig. 1). These sites were selected based on their representativeness of wheat-growing conditions in the district and the willingness of local farmers to allocate land and assist in managing the trials. Site selection was carried out in collaboration with agricultural officials and experts from the local extension system. The sites are five kilometers apart and have similar agricultural practices, soil management, and climatic conditions. The geographical coordinates of the experimental sites range from 07°12.081′ to 07°30.15′ N latitude and 38°11.566′ to 38°13.976′ E longitude, with altitudes varying between 1,926 and 2,040 meters above sea level. According to the data obtained from Halaba Meteorological Station (informal personal communication), the area receives an average annual rainfall ranging from 601 to 1,200 mm and experiences monthly minimum and maximum temperatures of approximately 18°C and 24°C, respectively. The terrain is gently sloping, with gradients between 2% and 2.5%. Major crops cultivated in the area include maize, wheat, teff, hot pepper, finger millet, and haricot bean. Figure 1. Map of the study area 2.2 Soil Sampling and Analysis Prior to planting, composite soil samples were collected from each site with the informed consent and permission of the respective farmers to assess baseline soil fertility. At each of the eight experimental sites, twenty surface soil samples (0–20 cm depth) were collected randomly in a zigzag pattern within the site and then combined to form one composite sample representing that specific site. The samples were air-dried and sieved through a 2-mm mesh for physical and chemical analyses. Particle size distribution was determined using the hydrometer method (Bouyoucos, 1962), soil pH was measured in a 1:2.5 soil-to-water ratio using a digital pH meter, available phosphorus (P) was determined using the Olsen method (Olsen, 1954), for organic carbon (OC) analysis, samples were further sieved to 0.5 mm and analyzed using the Walkley and Black (1934) wet oxidation method, total nitrogen (N) was measured using the Kjeldahl digestion method (Bremner & Mulvaney, 1982). 2.3. Soil Fertility Status of Farmers’ Fields The pre-treatment soil analysis results for various parameters were evaluated using the guidelines provided by Wogi et al. (2021). Based on this assessment, the soil pH at the experimental sites ranged from slightly acidic to neutral (6.06–6.99). Organic carbon (OC) content ranged from medium to high, with values between 1.85% and 4.19%. Most sites (5 out of 8 sites) exhibited high organic carbon levels, and the rest (3 out of 8 sites) had medium levels. According to the Olsen-P classification, available phosphorus (P) levels ranged from low to medium (3.101–10.936 mg/kg), while total nitrogen (N) was found to be within medium to very high ranges (0.084–0.294%). Notably,7 out of the 8 experimental fields were phosphorus-deficient, while only 1 out of 8 had medium phosphorus levels (Table 1 ). In terms of soil texture, 5 out of the 8 sites were classified as sandy loam, while the remaining 3 out of 8 sites were loam. Table 1 Some properties of soils of the experimental sites before planting Site pH OC (%) N (%) P (mg/kg) Sand (%) Clay (%) Silt (%) Textural class 1 6.99 2.145 0.084 8.953 53 17 30 Sandy loam 2 6.06 4.193 0.294 6.363 49 13 38 Loam 3 6.25 2.145 0.154 7.418 57 15 28 Sandy loam 4 7.28 1.853 0.140 7.994 47 19 34 Loam 5 6.89 3.413 0.210 10.936 55 15 30 Sandy loam 6 6.31 3.218 0.196 7.962 49 19 32 Loam 7 6.10 3.998 0.168 9.145 57 13 30 Sandy loam 8 6.56 3.120 0.112 3.101 55 13 32 Sandy loam Table 1 about here 2.4 Experimental Design and Treatments The field experiments were laid out in a Randomized Complete Block Design (RCBD) with three replications per site focusing on the effect of omitting one nutrient at a time (single-nutrient omission approach), alongside key reference treatments (complete, NP, and negative control). The test crop was wheat ( Triticum aestivum L.), using the high-yielding variety Ogolcho , which is recommended for the area. Treatments were based on nutrient omission principles to identify limiting nutrients. Ten treatments were established (Table 2 ): ( 1 ) NPKSZnB – All nutrients applied (complete treatment), ( 2 ) NPKSZn – Without boron (B), ( 3 ) NPKSB – Without zinc (Zn), ( 4 ) NPKZnB – Without sulfur (S), ( 5 ) NPSZnB – Without potassium (K), ( 6 ) NKSZnB – Without phosphorus (P), ( 7 ) PKSZnB – Without nitrogen (N), ( 8 ) Recommended NP (NP), ( 9 ) No nutrients – Negative control, and ( 10 ) NP + S2 NP plus elevated sulfur (30 kg S ha⁻¹). The application rates of N, P, K, S, Zn and B were 92, 20, 50, 10.5, 5, and 1.0 kgha − 1 , respectively. Whereas, the amount of S2 was 30 kgha − 1 to exhaustively study the effects of S on wheat response. Single source of the respective nutrients was used. The sources of N, P, K, S, Zn and B were urea [CO (NH2)2, 46% N], Triple Superphosphate (TSP), Potassium chloride (KCl), Magnesium sulfate (MgSO₄), Zn-EDTA (granular) and Borax (granular), respectively. Urea was applied in two splits—half at planting and half at 35 days after planting. All other fertilizers were applied at planting in granular form. 2.5 Agronomic Management The land was ploughed using ox-drawn implements, and the experiment was conducted under rainfed conditions. Each plot measured 4 × 3 meters, with 1-meter spacing between plots and blocks. Wheat seeds were sown in rows spaced 20 cm apart at a seeding rate of 100 kg ha⁻¹. Fertilizers were applied in rows according to the designated treatments. All plots were managed uniformly, including weeding and pest control practices. To manage yellow rust, the systemic fungicide Tilt® 250 EC was applied as needed. 2.6. Data Collection and Analysis Data were collected on wheat grain yield, biomass yield and yield components, including: number of tillers, plant height (measured at physiological maturity), and spike length. Measurements were taken from five randomly selected plants within each plot, excluding the border rows, and the results were averaged. Grain yield was harvested from the central sixteen rows (approximately 9.6 m²) of each plot. Biomass and grain were sun-dried to a constant weight before being weighed using a digital balance. Hundred seed weight (100-SW) was determined from randomly selected grain samples. Grain moisture content was measured using a Dickey-John Multigrain Moisture Tester, and grain yield was adjusted to 12.5% moisture content. All collected data were analyzed statistically using SAS software version 9.4, employing the General Linear Model (GLM) procedure to assess treatment effects. Mean separation was performed using the Least Significant Difference (LSD) method. A three-way ANOVA was initially conducted to assess the effects of fertilizer treatment, site, and replication on the measured variables: grain yield, above-ground biomass, tiller number, spike length, and hundred seed weight. The model included all main effects and their interactions (treatment × site × replication). The results of the main effects and two-way interactions are provided in Appendix Tables (2, 3, 4, 5, 6, & 7), offering a complete overview of the variance structure before data were pooled across sites for subsequent analyses. However, the three-way interaction term (treatment × site × replication) could not be tested because the model resulted in a zero-error term, rendering the F-test for this interaction undefined. This is a known limitation when certain combinations of factors lead to a saturated model with no degrees of freedom left for the residual. Since the interaction between sites and treatments was not significant, a combined analysis across locations was conducted. Table 2 Treatments set up, nutrient types and their description for field experiment No. Treatments Omitted nutrient (s) Description 1 All (NPKSZnB) None Recommended by the EthioSIS project 2 All – B B 3 All – Zn Zn 4 All –S S S-dose = 10.5 kg/ha 5 All - K K 6 All – P P 7 All-N N 8 NP B, Zn, K, S, Blanket recommendation of NP 9 No fertilizer All Negative control 10 NP + S2 B, Zn, K S-dose = 30 kg/ha Table 2 about here 3. Results 3.1 Effects of Nutrient Treatments on Wheat Performance The application of nutrient treatments had a very highly significant effect (p < 0.0001) on all measured wheat parameters, including grain yield, biomass yield, number of tillers, plant height, spike length, and hundred seed weight; however, the interaction between treatment and site was not significant for yield and most yield components (Appendix Tables 2, 3, 4, 5, 6, and 7). To further investigate, the site factor was decomposed into its components—soil pH, organic carbon, and soil phosphorus—and analyzed separately. However, the interaction remained non-significant, consistent with the original treatment × site interaction (Appendix Table 1). Nutrient omission analysis revealed that excluding boron (B), zinc (Zn), sulfur (S), or potassium (K) did not significantly impact wheat performance compared to the complete nutrient treatment (NPKSZnB). Grain yield and yield components under these omission treatments were statistically similar to those under full nutrient application (Fig. 2, Table 4, Table 5). Specifically, grain yield, biomass yield, number of fertile tillers, plant height, and spike length recorded under the complete nutrient treatment, B-omitted, Zn-omitted, S-omitted, K-omitted, NP (recommended nitrogen and phosphorus), and NP + S₂ (NP plus additional sulfur) treatments were statistically equivalent and significantly higher than those observed in the P-omitted, N-omitted, and negative control (no nutrients) treatments. Notably, the NP + S₂ treatment performed comparably to the complete nutrient treatment across all measured parameters, suggesting that elevated sulfur did not provide additional benefit beyond N and P under the conditions of this study. In contrast, the omission of nitrogen (N) and phosphorus (P) led to significant reductions in all yield parameters. This is in line with the finding by Kumar et al., (2019) who reported that the absence of key nutrients like Nitrogen or Phosphorus significantly reduced wheat yields. Among all nutrients tested, nitrogen omission caused the most severe decline. The highest yield penalty was observed in the negative control (36.68%), followed by nitrogen omission (31.33%) and phosphorus omission (12.32%). Omission of other nutrients resulted in negligible yield penalties. Yields under nitrogen omission were statistically equivalent to the negative control, confirming nitrogen as the most limiting nutrient in the study area. Although phosphorus omission also significantly reduced yield, its impact was less severe than that of nitrogen. The NP treatment produced grain yields and yield components that were statistically similar to those of the complete nutrient treatment, the NP + S₂ treatment, and treatments omitting B, Zn, S, and K. However, the NP treatment significantly outperformed the N-omitted, P-omitted, and negative control treatments. Interestingly, the N-omitted treatment recorded the highest 100-seed weight (37.54 g), while the P-omitted treatment had the lowest (33.42 g). The complete nutrient treatment resulted in a 100-seed weight that was significantly lower than the N-omitted treatment but significantly higher than the P-omitted treatment. Fig. 2 about here Fig. 3 about here Table 3: Effect of different nutrient on Yield components of wheat combined by location No. Treatment Tiller no. Plht (cm) SpL (cm) HSW (g) 1 All (NPKSZnB) 6.30abc 86.04a 8.80bc 35.33ef 2 All – B 6.53ab 86.72a 9.00ab 34.38g 3 All – Zn 6.80a 84.95a 9.00ab 36.96b 4 All –S 6.34abc 84.56a 8.97ab 35.71de 5 All - K 6.39abc 85.62a 9.188a 34.29g 6 All – P 5.88c 79.33b 8.44c 33.42h 7 All-N 4.71d 72.03c 7.20f 37.54a 8 NP 6.48ab 84.93a 8.99ab 35.04f 9 0 4.82d 74.02c 7.63d 36.54bc 10 NP+S2 (30 kg/ha) 6.18bc 86.15a 9.05ab 36.17cd p-values <.0001 <.0001 <.0001 <.0001 LSD (5%) 0.52 2.35 0.37 0.56 CV (%) 15.148 4.99 7.61 2.75 Plht=plant height; SpL= spike length; HSW=hundred seeds weight Table 4. Mean and standard deviation of yield and yield components as influenced by application of different nutrients Treatment GY (kg/ha) ABM (kg/ha) Tiller no. Plht (cm) SpL (cm) HSW (g) All (NPKSZnB) 3112.5±443.61 9495.83±2043.12 6.30±1.01 86.04±5.7 8.80±0.87 35.33±1.88 All – B 3125.0±613.79 9837.5±1275.1 6.53±1.26 86.72±7.35 9.00±0.92 34.375±3.87 All – Zn 2970.83±563.74 9600.00±1276.54 6.80±1.27 84.95±4.28 9.00±0.74 36.96±2.37 All –S 3104.17±520.43 9300.00±2095.75 6.34±1.01 84.56±6.30 8.97±0.77 35.71±1.85 All - K 3037.5±533.09 9691.67±1495.19 6.39±1.32 85.62±6.73 9.19±0.78 34.29±1.83 All – P 2729.17±607.55 8633.33±1576.64 5.88±1.36 79.33±7.88 8.44±0.97 33.42±1.53 All-N 2137.5±472.56 6216.66±1336.33 4.71±1.28 72.03±7.96 7.20±1.12 37.54±1.67 NP 3054.17±546.91 9825.00±1189.54 6.48±1.31 84.93±5.87 8.99±0.69 35.04±2.07 0 1970.83±482.28 5904.17±1180.82 4.82±1.18 74.01±8.47 7.63±0.92 36.54±1.32 NP+S2 (30 kg/ha) 2945.83±578.59 9304.16±1603.38 6.18±0.90 86.15±5.74 9.04±0.81 36.17±4.05 GY=grain yield; ABM=above ground biomass; Plht=plant height; SpL= spike length; HSW=hundred seeds weight Table 3 about here Table 4 about here 4. Discussion The pre-treatment soil analysis revealed that the soils across the experimental sites in Halaba, Central Ethiopia, were predominantly slightly acidic to neutral in pH (6.06–6.99), which is within the optimal range for wheat growth (Fageria et al., 2011). This pH range supports nutrient availability and microbial activity, both critical for crop productivity. In terms of texture, sandy loam was the dominant soil type, which typically offer good drainage and root penetration due to their coarse texture and large pore spaces, but they generally have lower nutrient- and water-holding capacities compared to finer-textured soils, which provide greater nutrient retention and moisture storage (Huntley, 2023)This further underscore the importance of balanced and timely nutrient application to match crop uptake patterns and minimize leaching losses (Brady & Weil, 2008). The organic carbon (OC) levels, ranging from medium to high (1.85–4.19%), suggest moderately fertile soils with reasonable organic matter content, which is beneficial for soil structure, microbial life, water retention and nutrient availability (Lal, 2004). The high organic carbon observed at 5 out of the 8 sites is consistent with findings from similar agro-ecological zones in sub-Saharan Africa where traditional residue return and limited tillage preserve organic matter (Kihara et al., 2016). However, available phosphorus levels were generally low to medium, with 7 out of the 8 sites classified as phosphorus-deficient based on the Olsen-P method. This widespread phosphorus deficiency highlights the limited use of phosphorus fertilizers in the region and underscores the need for adequate phosphorus supplementation to support optimal crop growth. The application of nutrient treatments significantly influenced all measured wheat growth and yield parameters (p < 0.0001), highlighting the essential role of adequate nutrition in crop productivity. This strong treatment effect aligns with global research indicating that nutrient management is among the most critical determinants of wheat yield potential (Fageria et al., 2011). The omission of B, Zn, S, or K did not significantly reduce wheat yield or yield components compared to the full nutrient treatment (NPKSZnB), suggesting that these nutrients were either present in sufficient quantities in the native soil or not limiting under the prevailing conditions. Similar findings were reported by Curtin et al. (2008), who found minimal response to micronutrient application in soils with sufficient background levels of Zn and B. However, the result contrasts with findings from other parts of Ethiopia (e.g., Wondo and Adami Tulu districts), where the omission of S, Zn, and B has led to significant yield reductions (Jewaro et al., 2020), indicating that the response to these nutrients is highly site-specific and dependent on local soil fertility status. In line with this result, although the omission of Zn did not significantly reduce wheat yield at most of the experimental sites, a greater yield reduction was observed due to Zn omission at three of sites—following the omission of N and P. This suggests that some sites in the study region may be affected by Zn deficiency, highlighting the need for future research to consider Zn application for wheat production. The discrepancy may be due to differences in soil parent material, cropping history, or fertilizer use intensity, implying that nutrient limitations are site-specific and cannot be generalized across regions. On the contrary, the omission of nitrogen and phosphorus led to significant yield penalties, with nitrogen omission causing the most substantial reduction (31.33%), followed by phosphorus (12.32%). Although the pretreatment soil analysis showed that total nitrogen ranged from medium to very high levels (0.084–0.294%), the negative control produced yields comparable to the N-omitted treatment. This indicates severe nitrogen deficiency in the study area, likely because total soil N does not necessarily represent plant-available nitrogen. While the medium to very high total N values suggest a substantial nitrogen pool, its availability may be constrained by slow mineralization under the prevailing conditions (e.g., soil type, moisture, temperature). Further research is needed to determine the specific factors limiting soil N mineralization in the study area including analysis of soil available N (nitrate (NO₃⁻) and ammonium (NH₄⁺)). These results are consistent with research across various wheat-growing regions where nitrogen is often the most yield-limiting nutrient due to its high plant demand and susceptibility to losses through leaching and volatilization (Ullah et al., 2024; Timsina & Connor, 2001; Sebnie et al., 2024). Phosphorus, though less limiting than nitrogen, remains critical for root development and early plant vigor. Its omission significantly reduced all measured parameters, confirming the low P availability identified during the pre-treatment soil analysis. The observed yield penalty is consistent with studies in East Africa and South Asia, where low P availability limits wheat productivity in smallholder systems (Bekele & Höfner, 1993; Sebnie et al., 2024). Interestingly, the NP (recommended nitrogen and phosphorus) and NP + S₂ (elevated sulfur) treatments produced yields and yield components statistically equivalent to the complete nutrient treatment, indicating that supplementing beyond N and P did not confer additional yield benefits. This suggests that under the study conditions, N and P are the primary nutrients limiting wheat productivity, and the native soil supply of other nutrients is adequate. Similar conclusions were drawn by Zingore et al. (2008) and Sebnie et al. (2024) in maize systems, where strategic application of N and P optimized returns. The fact that the NP treatment performed comparably to the complete nutrient treatment (NPKSZnB) implies that, in this context, the application of just nitrogen and phosphorus may be sufficient to achieve optimal wheat yield. This has practical implications for reducing input costs for farmers without sacrificing yield. It also highlights the inefficiency of applying non-limiting nutrients, which could lead to unnecessary environmental and financial costs. This aligns with the principle of 4R nutrient stewardship (Right source, Right rate, Right time, Right place), which aims to optimize fertilizer use for maximum productivity and sustainability (IFA, WFO, & GACSA, 2016). The unexpected finding that the N-omitted treatment produced the highest 100-seed weight (37.54 g) can be attributed to a compensatory effect, where fewer grains per plant led to greater assimilate allocation to each seed. Conversely, the P-omitted treatment yielded the lowest seed weight (33.42 g), reflecting the crucial role of phosphorus in grain filling and energy transfer. This result is in agreement with Noonari et al. (2016) who reported that application of P significantly increased 1000 seeds weight in wheat. Future studies could address several important factors. First, the interaction between wheat varieties and fertilization schemes, particularly in relation to nutrient uptake, warrants further investigation. Second, the role of water availability—whether drought or irrigation—in limiting wheat growth and constraining soil nitrogen mineralization and availability should be examined. Third, research could explore how variations in root architecture and soil microbial communities contribute to improved water and nutrient uptake. Beyond yield quantity, future studies should also evaluate the nutritional quality of wheat grains. While NP fertilization may increase yields, it is equally important that grains serve as a source of essential micronutrients for consumers. Future studies could therefore examine the contents of nutrients such as zinc, magnesium, and B-vitamins in the grains, linking this to broader issues of malnutrition and hidden hunger. Additionally, soil analyses for sulfur, potassium, zinc, and boron were not included in the present study, and should be incorporated in future work. Likewise, key parameters such as nutrient uptake, tissue nutrient concentrations, and nutrient use efficiency remain unaddressed and merit careful consideration in upcoming research. Finally, future studies should include baseline assessment of micronutrient levels as well as economic analyses of different blends. Such analyses would provide region-specific recommendations that are not only agronomically effective but also economically viable for growers and crop consultants. 5. Conclusions The study demonstrated that nitrogen and phosphorus are the most limiting nutrients for wheat production in the study area. Their omission resulted in significant yield penalties, with nitrogen showing the most drastic effect. Other nutrients, including B, Zn, S, and K, did not significantly affect yield or yield components, suggesting sufficient baseline availability in the soil. The comparable performance of the NP and full nutrient treatments indicates that focusing on N and P is both agronomically sound and economically efficient for wheat production under the studied conditions. Fertilizer management in this region should focus primarily on nitrogen (N) and phosphorus (P) as the key inputs for wheat production. The application of micronutrients and secondary nutrients such as boron (B), zinc (Zn), sulfur (S), and potassium (K) should be based on site-specific soil test results or confirmed deficiency symptoms to prevent unnecessary expenditure on inputs. Declarations Funding: This research was funded by the Ethiopian Institute of Agricultural Research (EIAR). Author Contribution A.A. analyzed the data and wrote the main manuscript text, prepared figures. M.T. assisted with conducting the field work and data collection. All authors reviewed and approved the final manuscript. Acknowledgement The authors acknowledge the Ethiopian Institute of Agricultural Research (EIAR) for funding this study. We are also grateful to the experimental farmers for providing land and supporting the implementation of the field experiments. Data Availability All data generated or analyzed during this study are included in this published article. References Abera, W., Tamene, L., Tesfaye, K., Jiménez, D., Dorado, H., Erkossa, T., et al. A data-mining approach for developing site-specific fertilizer response functions across the wheat-growing environments in Ethiopia. Exp. Agric. 58 , e9 (2022). Bekele, T. & Höfner, W. Effects of different phosphate fertilizers on yield of barley and rape seed on reddish brown soils of the Ethiopian highlands. Fertil. Res. 34 , 243–250 (1993). Bouyoucos, G. J. Hydrometer method improved for making particle size analyses of soils. Agron. J. 54 (5), 464–465 (1962). Brady, N. C. & Weil, R. R. The Nature and Properties of Soils (14th ed.). Prentice Hall (2008). Bremner, J. M. & Mulvaney, C. S. Nitrogen—total. Methods of Soil Analysis: Part 2. Chemical and Microbiological Properties 9 , 595–624 (1982). CSA. Agricultural Sample Survey 2006–07. Volume I . Addis Ababa (2007). Curtin, D., Martin, R. J. & Scott, C. L. Wheat ( Triticum aestivum ) response to micronutrients (Mn, Cu, Zn, B) in Canterbury, New Zealand. N. Z. J. Crop Hortic. Sci. 36 (3), 169–181 (2008). https://doi.org/10.1080/01140670809510233 Fageria, N. K., Baligar, V. C. & Jones, C. A. Growth and Mineral Nutrition of Field Crops . CRC Press (2011). Getinet, H., Abera, K. & Lulie, B. Identifying limiting nutrients for wheat production through omission plot experiment on Nitisols of East Gojjam Zone, North Western Ethiopia. Am. J. Appl. Sci. Res. 8 (2), 49–56 (2024). Giraldo, P., Benavente, E., Manzano-Agugliaro, F. & Gimenez, E. Worldwide research trends on wheat and barley: A bibliometric comparative analysis. Agronomy 9 (7), 352 (2019). Hodson, D. P., Jaleta, M., Tesfaye, K., Yirga, C., Beyene, H., Kilian, A., et al. Ethiopia’s transforming wheat landscape: tracking variety use through DNA fingerprinting. Sci. Rep. 10 , 18532 (2020). Huntley, B. J. Soil, Water and Nutrients. In Ecology of Angola . Springer, Cham (2023). https://doi.org/10.1007/978-3-031-18923-4_6 IFA, WFO & GACSA. Nutrient Management Handbook . 1st ed. (2016). Jewaro, H., Kefale, D. & Yoseph, T. Effects of blended fertilizer types and rates on growth, yield and yield component of bread wheat ( Triticum aestivum L.) in Wondo district, southern Ethiopia. Int. J. Agric. Innov. Res. 8 , 2319–1473 (2020). Kihara, J., Nziguheba, G., Zingore, S., Coulibaly, A., Esilaba, A., Kabambe, V., et al. Understanding variability in crop response to fertilizer and amendments in sub-Saharan Africa. Agric. Ecosyst. Environ. 229 , 1–12 (2016). Kumar, P., Shivay, Y. S. & Pooniya, V. Nutrient management for improving wheat ( Triticum aestivum L.) productivity and soil fertility. J. Plant Nutr. 42 (12), 1439–1456 (2019). Lal, R. Soil carbon sequestration impacts on global climate change and food security. Science 304 (5677), 1623–1627 (2004). MoARD. National Fertilizer Strategy and Action Plan of Ethiopia . Addis Ababa, Ethiopia (2008). Noonari, S., Kalhoro, S. A., Ali, A., Mahar, A., Raza, S., Ahmed, M., et al. Effect of different levels of phosphorus and method of application on the growth and yield of wheat. Nat. Sci. 8 (7), 305–314 (2016). Olsen, S. R. Estimation of available phosphorus in soils by extraction with sodium bicarbonate. USDA Circular No. 939 (1954). Richards, M. B., Butterbach-Bahl, K., Jat, M. L., Ortíz Monasterio, J. I., Sapkota, T. B. & Lipinski, B. Site-Specific Nutrient Management: Implementation Guidance for Policymakers and Investors (2015). Sebnie, W., Melak, E. & Lamesgn, H. Effects of nutrient omission on grain and biomass yield of irrigated wheat ( Triticum aestivum ) in Sekota district, Amhara region, Ethiopia. Environ. Res. Commun. 6 (11), 115013 (2024). Senbeta, A. F. & Worku, W. Ethiopia’s wheat production pathways to self-sufficiency through land area expansion, irrigation advance, and yield gap closure. Heliyon 9 (10) (2023). Solomon, W. & Anjulo, A. Response of bread wheat varieties to different levels of nitrogen at Doyogena, Southern Ethiopia. Int. J. Sci. Res. Public. 7 (2), 452–459 (2017). Tamene, L., Amede, T., Kihara, J., Tibebe, D. & Schulz, S. A review of soil fertility management and crop response to fertilizer application in Ethiopia: towards development of site- and context-specific fertilizer recommendation. Technical Report. CIAT, Addis Ababa, Ethiopia (2017). Tehulie, N. S. Response of bread wheat ( Triticum aestivum L.) varieties to nitrogen fertilizer rates at Mekdela District, South Wollo, Ethiopia. Sci. Pap. Ser. A. Agron. 64 (2), 294–302 (2021). Timsina, J. & Connor, D. J. Productivity and management of rice–wheat cropping systems: issues and challenges. Field Crops Res. 69 (2), 93–132 (2001). Ullah, B., Lou, H., Arif, M., Zhang, S., Khan, H. A., Sadozai, K. N., et al. Optimizing NPK fertilization for enhanced performance of Chinese wheat hybrids under agro-climatic condition of Peshawar Valley. Agronomy 14 (9), 1904 (2024). Walkley, A. & Black, I. A. An examination of the Degtjareff method for determining soil organic matter, and a proposed modification of the chromic acid titration method. Soil Sci. 37 (1), 29–38 (1934). Wogi, L., Dechassa, N., Haileselassie, B., Mekuria, F., Abebe, A. & Tamene, L. A Guide to Standardized Methods of Analysis for Soil, Water, Plant, and Fertilizer Resources for Data Documentation and Sharing in Ethiopia . CIAT Publication No. 519. CIAT, Addis Ababa, Ethiopia, 41 p. (2021). Zingore, S., Delve, R. J., Nyamangara, J. & Giller, K. E. Multiple benefits of manure: the key to maintenance of soil fertility and restoration of depleted sandy soils on African smallholder farms. Nutr. Cycl. Agroecosyst. 80 , 267–282 (2008). Additional Declarations No competing interests reported. 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Introduction","content":"\u003cp\u003eWheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) is a vital staple crop, feeding about one-third of the worldwide population, delivering half of nutritional protein, and more than half of calories. It is cultivated on around 218\u0026nbsp;million hectares worldwide, with an average yield of 3.3 t/ha (Giraldo et al., 2019). In Ethiopia, wheat ranks fourth in terms of area cultivated\u0026mdash;after tef (\u003cem\u003eEragrostis tef\u003c/em\u003e Zucc.), maize (\u003cem\u003eZea mays\u003c/em\u003e L.), and sorghum (\u003cem\u003eSorghum bicolor\u003c/em\u003e L. Moench)\u0026mdash;but is second only to maize in terms of consumption (Solomon and Anjulo, 2017; CSA, 2007; Hodson et al., 2020).\u003c/p\u003e\u003cp\u003eDespite the crop\u0026rsquo;s significance and extensive cultivation, Ethiopia\u0026rsquo;s national average wheat yield remains low, at just 2.2 t/ha\u0026mdash;significantly below its potential yield of 8.3 t/ha (Senbeta and Worku, 2023). This yield gap is largely attributed to factors such as soil fertility depletion due to intensive nutrient mining, and the continued use of blanket fertilizer recommendations that fail to account for local soil nutrient variability (MoARD, 2008). One of the challenges in Ethiopia is the widespread use of \u0026lsquo;blanket\u0026rsquo; recommendations\u0026ndash; whereby a single fertilizer rate is prescribed for a large area or across the entire country (Abera et al., 2022). Farmers in Halaba area apply blanket fertilizer recommendation for wheat production. Such generalized fertilizer application limits productivity and leads to inefficient nutrient uptake (IFA, WFO, \u0026amp; GACSA, 2016) calling for the development of site-specific nutrient management option. Site-Specific Nutrient Management (SSNM) optimizes nutrient supply in space and time to meet crop requirements, thereby enhancing productivity and fertilizer use efficiency (Richards, 2015). The nutrient omission technique, a key approach in SSNM, provides a systematic framework to assess the soil\u0026rsquo;s inherent nutrient-supplying capacity and guide site-specific fertilizer application (Getinet et al., 2024).\u003c/p\u003e\u003cp\u003eRecent research highlights that, while nitrogen (N), phosphorus (P), and potassium (K) are commonly deficient, secondary and micronutrients such as sulfur (S), zinc (Zn), and boron (B) are increasingly recognized as limiting factors for crop growth globally (Tamene et al., 2017; IFA et al., 2016). Nutrient omission trials across Ethiopia have confirmed that deficiencies in N, P, K, S, Zn, and B can significantly limit crop productivity depending on the agro-ecological context (Fageria et al., 2011). For instance, a study in Wondo District, Oromia Region, demonstrated that application of blended fertilizers containing N, P, S, and B significantly improved key wheat growth parameters, including plant height, spike length, fertile tiller count, straw yield, and grain yield (Jewaro et al., 2020). Similarly, another study in South Wollo, Amhara Region, reported significant yield improvements with nitrogen fertilizer application alone (Tehulie, 2021).\u003c/p\u003e\u003cp\u003eIn areas like Halaba in the Central Ethiopia Region, where detailed nutrient diagnostics are limited, identifying specific nutrient constraints is critical to improving wheat yields and promoting efficient, sustainable fertilizer use. While nitrogen and phosphorus have received substantial attention, the roles of K, S, Zn, and B in this region remain underexplored.\u003c/p\u003e\u003cp\u003eTherefore, the objective of this study was to identify the most limiting nutrient(s) for wheat production in Halaba through field-based nutrient omission trials. The main hypothesis is that one or more nutrients in the soils of the study area limit wheat production. The results will support the development of site-specific nutrient management strategies, contributing to increased wheat productivity, improved fertilizer efficiency, and more sustainable agricultural practices in the region.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n \u003ch2\u003e2.1 Description of the Study Area\u003c/h2\u003e\n \u003cp\u003eThe experiment was conducted during the 2021 cropping season at eight locations within the Wera Dijo District, Halaba Zone, Central Ethiopia (Fig.\u0026nbsp;1). These sites were selected based on their representativeness of wheat-growing conditions in the district and the willingness of local farmers to allocate land and assist in managing the trials. Site selection was carried out in collaboration with agricultural officials and experts from the local extension system. The sites are five kilometers apart and have similar agricultural practices, soil management, and climatic conditions.\u003c/p\u003e\n \u003cp\u003eThe geographical coordinates of the experimental sites range from 07\u0026deg;12.081\u0026prime; to 07\u0026deg;30.15\u0026prime; N latitude and 38\u0026deg;11.566\u0026prime; to 38\u0026deg;13.976\u0026prime; E longitude, with altitudes varying between 1,926 and 2,040 meters above sea level. According to the data obtained from Halaba Meteorological Station (informal personal communication), the area receives an average annual rainfall ranging from 601 to 1,200 mm and experiences monthly minimum and maximum temperatures of approximately 18\u0026deg;C and 24\u0026deg;C, respectively. The terrain is gently sloping, with gradients between 2% and 2.5%. Major crops cultivated in the area include maize, wheat, teff, hot pepper, finger millet, and haricot bean.\u003c/p\u003e\n \u003cp\u003eFigure\u0026nbsp;1. Map of the study area\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n \u003ch2\u003e2.2 Soil Sampling and Analysis\u003c/h2\u003e\n \u003cp\u003ePrior to planting, composite soil samples were collected from each site with the informed consent and permission of the respective farmers to assess baseline soil fertility. At each of the eight experimental sites, twenty surface soil samples (0\u0026ndash;20 cm depth) were collected randomly in a zigzag pattern within the site and then combined to form one composite sample representing that specific site. The samples were air-dried and sieved through a 2-mm mesh for physical and chemical analyses. Particle size distribution was determined using the hydrometer method (Bouyoucos, 1962), soil pH was measured in a 1:2.5 soil-to-water ratio using a digital pH meter, available phosphorus (P) was determined using the Olsen method (Olsen, 1954), for organic carbon (OC) analysis, samples were further sieved to 0.5 mm and analyzed using the Walkley and Black (1934) wet oxidation method, total nitrogen (N) was measured using the Kjeldahl digestion method (Bremner \u0026amp; Mulvaney, 1982).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n \u003ch2\u003e2.3. Soil Fertility Status of Farmers\u0026rsquo; Fields\u003c/h2\u003e\n \u003cp\u003eThe pre-treatment soil analysis results for various parameters were evaluated using the guidelines provided by Wogi et al. (2021). Based on this assessment, the soil pH at the experimental sites ranged from slightly acidic to neutral (6.06\u0026ndash;6.99). Organic carbon (OC) content ranged from medium to high, with values between 1.85% and 4.19%. Most sites (5 out of 8 sites) exhibited high organic carbon levels, and the rest (3 out of 8 sites) had medium levels. According to the Olsen-P classification, available phosphorus (P) levels ranged from low to medium (3.101\u0026ndash;10.936 mg/kg), while total nitrogen (N) was found to be within medium to very high ranges (0.084\u0026ndash;0.294%). Notably,7 out of the 8 experimental fields were phosphorus-deficient, while only 1 out of 8 had medium phosphorus levels (Table \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). In terms of soil texture, 5 out of the 8 sites were classified as sandy loam, while the remaining 3 out of 8 sites were loam.\u003c/p\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003ctable id=\"Tab1\" border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eSome properties of soils of the experimental sites before planting\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSite\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003epH\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOC (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eN (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eP (mg/kg)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSand (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eClay (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSilt (%)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTextural class\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.145\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.084\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e8.953\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e53\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSandy loam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4.193\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.294\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.363\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLoam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.145\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.154\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e7.418\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSandy loam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e7.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.853\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.140\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e7.994\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLoam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.89\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.413\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.210\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e10.936\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e15\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSandy loam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.218\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.196\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e7.962\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e49\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLoam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.998\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.168\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e9.145\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSandy loam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e6.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.120\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.112\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.101\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSandy loam\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003c/p\u003e\n \u003cp\u003eTable \u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e \u003cstrong\u003eabout here\u003c/strong\u003e\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section2\"\u003e\n \u003ch2\u003e2.4 Experimental Design and Treatments\u003c/h2\u003e\n \u003cp\u003eThe field experiments were laid out in a Randomized Complete Block Design (RCBD) with three replications per site focusing on the effect of omitting one nutrient at a time (single-nutrient omission approach), alongside key reference treatments (complete, NP, and negative control). The test crop was wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.), using the high-yielding variety \u003cem\u003eOgolcho\u003c/em\u003e, which is recommended for the area. Treatments were based on nutrient omission principles to identify limiting nutrients. Ten treatments were established (Table \u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e): (\u003cspan class=\"CitationRef\"\u003e1\u003c/span\u003e) NPKSZnB \u0026ndash; All nutrients applied (complete treatment), (\u003cspan class=\"CitationRef\"\u003e2\u003c/span\u003e) NPKSZn \u0026ndash; Without boron (B), (\u003cspan class=\"CitationRef\"\u003e3\u003c/span\u003e) NPKSB \u0026ndash; Without zinc (Zn), (\u003cspan class=\"CitationRef\"\u003e4\u003c/span\u003e) NPKZnB \u0026ndash; Without sulfur (S), (\u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e) NPSZnB \u0026ndash; Without potassium (K), (\u003cspan class=\"CitationRef\"\u003e6\u003c/span\u003e) NKSZnB \u0026ndash; Without phosphorus (P), (\u003cspan class=\"CitationRef\"\u003e7\u003c/span\u003e) PKSZnB \u0026ndash; Without nitrogen (N), (\u003cspan class=\"CitationRef\"\u003e8\u003c/span\u003e) Recommended NP (NP), (\u003cspan class=\"CitationRef\"\u003e9\u003c/span\u003e) No nutrients \u0026ndash; Negative control, and (\u003cspan class=\"CitationRef\"\u003e10\u003c/span\u003e) NP\u0026thinsp;+\u0026thinsp;S2 NP plus elevated sulfur (30 kg S ha⁻\u0026sup1;). The application rates of N, P, K, S, Zn and B were 92, 20, 50, 10.5, 5, and 1.0 kgha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively. Whereas, the amount of S2 was 30 kgha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e to exhaustively study the effects of S on wheat response. Single source of the respective nutrients was used. The sources of N, P, K, S, Zn and B were urea [CO (NH2)2, 46% N], Triple Superphosphate (TSP), Potassium chloride (KCl), Magnesium sulfate (MgSO₄), Zn-EDTA (granular) and Borax (granular), respectively.\u003c/p\u003e\n \u003cp\u003eUrea was applied in two splits\u0026mdash;half at planting and half at 35 days after planting. All other fertilizers were applied at planting in granular form.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n \u003ch2\u003e2.5 Agronomic Management\u003c/h2\u003e\n \u003cp\u003eThe land was ploughed using ox-drawn implements, and the experiment was conducted under rainfed conditions. Each plot measured 4 \u0026times; 3 meters, with 1-meter spacing between plots and blocks. Wheat seeds were sown in rows spaced 20 cm apart at a seeding rate of 100 kg ha⁻\u0026sup1;. Fertilizers were applied in rows according to the designated treatments. All plots were managed uniformly, including weeding and pest control practices. To manage yellow rust, the systemic fungicide Tilt\u0026reg; 250 EC was applied as needed.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n \u003ch2\u003e2.6. Data Collection and Analysis\u003c/h2\u003e\n \u003cp\u003eData were collected on wheat grain yield, biomass yield and yield components, including: number of tillers, plant height (measured at physiological maturity), and spike length. Measurements were taken from five randomly selected plants within each plot, excluding the border rows, and the results were averaged. Grain yield was harvested from the central sixteen rows (approximately 9.6 m\u0026sup2;) of each plot. Biomass and grain were sun-dried to a constant weight before being weighed using a digital balance. Hundred seed weight (100-SW) was determined from randomly selected grain samples. Grain moisture content was measured using a Dickey-John Multigrain Moisture Tester, and grain yield was adjusted to 12.5% moisture content.\u003c/p\u003e\n \u003cp\u003eAll collected data were analyzed statistically using SAS software version 9.4, employing the General Linear Model (GLM) procedure to assess treatment effects. Mean separation was performed using the Least Significant Difference (LSD) method. A three-way ANOVA was initially conducted to assess the effects of fertilizer treatment, site, and replication on the measured variables: grain yield, above-ground biomass, tiller number, spike length, and hundred seed weight. The model included all main effects and their interactions (treatment \u0026times; site \u0026times; replication). The results of the main effects and two-way interactions are provided in Appendix Tables\u0026nbsp;(2, 3, 4, 5, 6, \u0026amp; 7), offering a complete overview of the variance structure before data were pooled across sites for subsequent analyses. However, the three-way interaction term (treatment \u0026times; site \u0026times; replication) could not be tested because the model resulted in a zero-error term, rendering the F-test for this interaction undefined. This is a known limitation when certain combinations of factors lead to a saturated model with no degrees of freedom left for the residual. Since the interaction between sites and treatments was not significant, a combined analysis across locations was conducted.\u003c/p\u003e\n \u003ctable border=\"1\"\u003e\n \u003ccaption language=\"En\"\u003e\n \u003cdiv\u003eTable 2\u003c/div\u003e\n \u003cdiv\u003e\n \u003cp\u003eTreatments set up, nutrient types and their description for field experiment\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNo.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTreatments\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eOmitted nutrient (s)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDescription\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll (NPKSZnB)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNone\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRecommended by the EthioSIS project\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll \u0026ndash; B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll \u0026ndash; Zn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eZn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll \u0026ndash;S\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eS\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eS-dose\u0026thinsp;=\u0026thinsp;10.5 kg/ha\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll - K\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eK\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll \u0026ndash; P\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll-N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB, Zn, K, S,\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBlanket recommendation of NP\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNo fertilizer\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAll\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNegative control\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNP\u0026thinsp;+\u0026thinsp;S2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eB, Zn, K\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eS-dose\u0026thinsp;=\u0026thinsp;30 kg/ha\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003eTable\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e \u003cstrong\u003eabout here\u003c/strong\u003e\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003e\u003cstrong\u003e3.1 Effects of Nutrient Treatments on Wheat Performance\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe application of nutrient treatments had a very highly significant effect (p \u0026lt; 0.0001) on all measured wheat parameters, including grain yield, biomass yield, number of tillers, plant height, spike length, and hundred seed weight; however, the interaction between treatment and site was not significant for yield and most yield components (Appendix Tables 2, 3, 4, 5, 6, and 7). To further investigate, the site factor was decomposed into its components\u0026mdash;soil pH, organic carbon, and soil phosphorus\u0026mdash;and analyzed separately. However, the interaction remained non-significant, consistent with the original treatment \u0026times; site interaction (Appendix Table 1).\u003c/p\u003e\n\u003cp\u003eNutrient omission analysis revealed that excluding boron (B), zinc (Zn), sulfur (S), or potassium (K) did not significantly impact wheat performance compared to the complete nutrient treatment (NPKSZnB). Grain yield and yield components under these omission treatments were statistically similar to those under full nutrient application (Fig. 2, Table 4, Table 5). Specifically, grain yield, biomass yield, number of fertile tillers, plant height, and spike length recorded under the complete nutrient treatment, B-omitted, Zn-omitted, S-omitted, K-omitted, NP (recommended nitrogen and phosphorus), and NP + S₂ (NP plus additional sulfur) treatments were statistically equivalent and significantly higher than those observed in the P-omitted, N-omitted, and negative control (no nutrients) treatments.\u003c/p\u003e\n\u003cp\u003eNotably, the NP + S₂ treatment performed comparably to the complete nutrient treatment across all measured parameters, suggesting that elevated sulfur did not provide additional benefit beyond N and P under the conditions of this study. In contrast, the omission of nitrogen (N) and phosphorus (P) led to significant reductions in all yield parameters. This is in line with the finding by Kumar et al., (2019) who reported that the absence of key nutrients like Nitrogen or Phosphorus significantly reduced wheat yields. Among all nutrients tested, nitrogen omission caused the most severe decline. The highest yield penalty was observed in the negative control (36.68%), followed by nitrogen omission (31.33%) and phosphorus omission (12.32%). Omission of other nutrients resulted in negligible yield penalties.\u003c/p\u003e\n\u003cp\u003eYields under nitrogen omission were statistically equivalent to the negative control, confirming nitrogen as the most limiting nutrient in the study area. Although phosphorus omission also significantly reduced yield, its impact was less severe than that of nitrogen. The NP treatment produced grain yields and yield components that were statistically similar to those of the complete nutrient treatment, the NP + S₂ treatment, and treatments omitting B, Zn, S, and K. However, the NP treatment significantly outperformed the N-omitted, P-omitted, and negative control treatments.\u003c/p\u003e\n\u003cp\u003eInterestingly, the N-omitted treatment recorded the highest 100-seed weight (37.54 g), while the P-omitted treatment had the lowest (33.42 g). The complete nutrient treatment resulted in a 100-seed weight that was significantly lower than the N-omitted treatment but significantly higher than the P-omitted treatment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFig. 2 about here\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFig. 3 about here\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3: \u0026nbsp;Effect of different nutrient on Yield components of wheat combined by location\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"510\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eNo.\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTreatment\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTiller no.\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePlht (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpL (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHSW (g)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll (NPKSZnB)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.30abc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e86.04a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e8.80bc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e35.33ef\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll \u0026ndash; B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.53ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e86.72a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e9.00ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e34.38g\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll \u0026ndash; Zn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.80a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e84.95a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e9.00ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e36.96b\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll \u0026ndash;S\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.34abc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e84.56a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e8.97ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e35.71de\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll - \u0026nbsp;K\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.39abc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e85.62a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e9.188a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e34.29g\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll \u0026ndash; P\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e5.88c\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e79.33b\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e8.44c\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e33.42h\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eAll-N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e4.71d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e72.03c\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e7.20f\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e37.54a\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eNP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.48ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e84.93a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e8.99ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e35.04f\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e4.82d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e74.02c\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e7.63d\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e36.54bc\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eNP+S2 (30 kg/ha)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e6.18bc\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e86.15a\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e9.05ab\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e36.17cd\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003ep-values\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026lt;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026lt;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e\u0026lt;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e\u0026lt;.0001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eLSD (5%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e0.52\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e2.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e0.37\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e0.56\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 39px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 105px;\"\u003e\n \u003cp\u003eCV (%)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e15.148\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e4.99\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 90px;\"\u003e\n \u003cp\u003e7.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 96px;\"\u003e\n \u003cp\u003e2.75\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003ePlht=plant height; SpL= spike length; HSW=hundred seeds weight\u003c/p\u003e\n\u003cp\u003eTable 4. Mean and standard deviation of yield and yield components as influenced by application of different nutrients\u0026nbsp;\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"682\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eTreatment\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eGY (kg/ha)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eABM (kg/ha)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTiller no.\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePlht (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpL (cm)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eHSW (g)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll (NPKSZnB)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e3112.5\u0026plusmn;443.61\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9495.83\u0026plusmn;2043.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.30\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e86.04\u0026plusmn;5.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e8.80\u0026plusmn;0.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e35.33\u0026plusmn;1.88\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll \u0026ndash; B\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e3125.0\u0026plusmn;613.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9837.5\u0026plusmn;1275.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.53\u0026plusmn;1.26\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e86.72\u0026plusmn;7.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e9.00\u0026plusmn;0.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e34.375\u0026plusmn;3.87\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll \u0026ndash; Zn\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e2970.83\u0026plusmn;563.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9600.00\u0026plusmn;1276.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.80\u0026plusmn;1.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e84.95\u0026plusmn;4.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e9.00\u0026plusmn;0.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e36.96\u0026plusmn;2.37\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll \u0026ndash;S\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e3104.17\u0026plusmn;520.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9300.00\u0026plusmn;2095.75\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.34\u0026plusmn;1.01\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e84.56\u0026plusmn;6.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e8.97\u0026plusmn;0.77\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e35.71\u0026plusmn;1.85\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll - \u0026nbsp;K\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e3037.5\u0026plusmn;533.09\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9691.67\u0026plusmn;1495.19\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.39\u0026plusmn;1.32\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e85.62\u0026plusmn;6.73\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e9.19\u0026plusmn;0.78\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e34.29\u0026plusmn;1.83\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll \u0026ndash; P\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e2729.17\u0026plusmn;607.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e8633.33\u0026plusmn;1576.64\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e5.88\u0026plusmn;1.36\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e79.33\u0026plusmn;7.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e8.44\u0026plusmn;0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e33.42\u0026plusmn;1.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eAll-N\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e2137.5\u0026plusmn;472.56\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e6216.66\u0026plusmn;1336.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e4.71\u0026plusmn;1.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e72.03\u0026plusmn;7.96\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e7.20\u0026plusmn;1.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e37.54\u0026plusmn;1.67\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eNP\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e3054.17\u0026plusmn;546.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9825.00\u0026plusmn;1189.54\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.48\u0026plusmn;1.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e84.93\u0026plusmn;5.87\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e8.99\u0026plusmn;0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e35.04\u0026plusmn;2.07\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003e0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e1970.83\u0026plusmn;482.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e5904.17\u0026plusmn;1180.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e4.82\u0026plusmn;1.18\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e74.01\u0026plusmn;8.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e7.63\u0026plusmn;0.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e36.54\u0026plusmn;1.32\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 94px;\"\u003e\n \u003cp\u003eNP+S2 (30 kg/ha)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 119px;\"\u003e\n \u003cp\u003e2945.83\u0026plusmn;578.59\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 127px;\"\u003e\n \u003cp\u003e9304.16\u0026plusmn;1603.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e6.18\u0026plusmn;0.90\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 87px;\"\u003e\n \u003cp\u003e86.15\u0026plusmn;5.74\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 79px;\"\u003e\n \u003cp\u003e9.04\u0026plusmn;0.81\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd valign=\"top\" style=\"width: 95px;\"\u003e\n \u003cp\u003e36.17\u0026plusmn;4.05\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003eGY=grain yield; ABM=above ground biomass; Plht=plant height; SpL= spike length; HSW=hundred seeds weight\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3 about here\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4 about here\u003c/strong\u003e\u0026nbsp;\u003c/p\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eThe pre-treatment soil analysis revealed that the soils across the experimental sites in Halaba, Central Ethiopia, were predominantly slightly acidic to neutral in pH (6.06\u0026ndash;6.99), which is within the optimal range for wheat growth (Fageria et al., 2011). This pH range supports nutrient availability and microbial activity, both critical for crop productivity. In terms of texture, sandy loam was the dominant soil type, which typically offer good drainage and root penetration due to their coarse texture and large pore spaces, but they generally have lower nutrient- and water-holding capacities compared to finer-textured soils, which provide greater nutrient retention and moisture storage (Huntley, 2023)This further underscore the importance of balanced and timely nutrient application to match crop uptake patterns and minimize leaching losses (Brady \u0026amp; Weil, 2008).\u003c/p\u003e\u003cp\u003eThe organic carbon (OC) levels, ranging from medium to high (1.85\u0026ndash;4.19%), suggest moderately fertile soils with reasonable organic matter content, which is beneficial for soil structure, microbial life, water retention and nutrient availability (Lal, 2004). The high organic carbon observed at 5 out of the 8 sites is consistent with findings from similar agro-ecological zones in sub-Saharan Africa where traditional residue return and limited tillage preserve organic matter (Kihara et al., 2016).\u003c/p\u003e\u003cp\u003eHowever, available phosphorus levels were generally low to medium, with 7 out of the 8 sites classified as phosphorus-deficient based on the Olsen-P method. This widespread phosphorus deficiency highlights the limited use of phosphorus fertilizers in the region and underscores the need for adequate phosphorus supplementation to support optimal crop growth.\u003c/p\u003e\u003cp\u003eThe application of nutrient treatments significantly influenced all measured wheat growth and yield parameters (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001), highlighting the essential role of adequate nutrition in crop productivity. This strong treatment effect aligns with global research indicating that nutrient management is among the most critical determinants of wheat yield potential (Fageria et al., 2011).\u003c/p\u003e\u003cp\u003eThe omission of B, Zn, S, or K did not significantly reduce wheat yield or yield components compared to the full nutrient treatment (NPKSZnB), suggesting that these nutrients were either present in sufficient quantities in the native soil or not limiting under the prevailing conditions. Similar findings were reported by Curtin et al. (2008), who found minimal response to micronutrient application in soils with sufficient background levels of Zn and B.\u003c/p\u003e\u003cp\u003eHowever, the result contrasts with findings from other parts of Ethiopia (e.g., Wondo and Adami Tulu districts), where the omission of S, Zn, and B has led to significant yield reductions (Jewaro et al., 2020), indicating that the response to these nutrients is highly site-specific and dependent on local soil fertility status. In line with this result, although the omission of Zn did not significantly reduce wheat yield at most of the experimental sites, a greater yield reduction was observed due to Zn omission at three of sites\u0026mdash;following the omission of N and P. This suggests that some sites in the study region may be affected by Zn deficiency, highlighting the need for future research to consider Zn application for wheat production. The discrepancy may be due to differences in soil parent material, cropping history, or fertilizer use intensity, implying that nutrient limitations are site-specific and cannot be generalized across regions.\u003c/p\u003e\u003cp\u003eOn the contrary, the omission of nitrogen and phosphorus led to significant yield penalties, with nitrogen omission causing the most substantial reduction (31.33%), followed by phosphorus (12.32%). Although the pretreatment soil analysis showed that total nitrogen ranged from medium to very high levels (0.084\u0026ndash;0.294%), the negative control produced yields comparable to the N-omitted treatment. This indicates severe nitrogen deficiency in the study area, likely because total soil N does not necessarily represent plant-available nitrogen. While the medium to very high total N values suggest a substantial nitrogen pool, its availability may be constrained by slow mineralization under the prevailing conditions (e.g., soil type, moisture, temperature). Further research is needed to determine the specific factors limiting soil N mineralization in the study area including analysis of soil available N (nitrate (NO₃⁻) and ammonium (NH₄⁺)).\u003c/p\u003e\u003cp\u003eThese results are consistent with research across various wheat-growing regions where nitrogen is often the most yield-limiting nutrient due to its high plant demand and susceptibility to losses through leaching and volatilization (Ullah et al., 2024; Timsina \u0026amp; Connor, 2001; Sebnie et al., 2024).\u003c/p\u003e\u003cp\u003ePhosphorus, though less limiting than nitrogen, remains critical for root development and early plant vigor. Its omission significantly reduced all measured parameters, confirming the low P availability identified during the pre-treatment soil analysis. The observed yield penalty is consistent with studies in East Africa and South Asia, where low P availability limits wheat productivity in smallholder systems (Bekele \u0026amp; H\u0026ouml;fner, 1993; Sebnie et al., 2024).\u003c/p\u003e\u003cp\u003eInterestingly, the NP (recommended nitrogen and phosphorus) and NP\u0026thinsp;+\u0026thinsp;S₂ (elevated sulfur) treatments produced yields and yield components statistically equivalent to the complete nutrient treatment, indicating that supplementing beyond N and P did not confer additional yield benefits. This suggests that under the study conditions, N and P are the primary nutrients limiting wheat productivity, and the native soil supply of other nutrients is adequate. Similar conclusions were drawn by Zingore et al. (2008) and Sebnie et al. (2024) in maize systems, where strategic application of N and P optimized returns. The fact that the NP treatment performed comparably to the complete nutrient treatment (NPKSZnB) implies that, in this context, the application of just nitrogen and phosphorus may be sufficient to achieve optimal wheat yield. This has practical implications for reducing input costs for farmers without sacrificing yield. It also highlights the inefficiency of applying non-limiting nutrients, which could lead to unnecessary environmental and financial costs. This aligns with the principle of 4R nutrient stewardship (Right source, Right rate, Right time, Right place), which aims to optimize fertilizer use for maximum productivity and sustainability (IFA, WFO, \u0026amp; GACSA, 2016).\u003c/p\u003e\u003cp\u003eThe unexpected finding that the N-omitted treatment produced the highest 100-seed weight (37.54 g) can be attributed to a compensatory effect, where fewer grains per plant led to greater assimilate allocation to each seed. Conversely, the P-omitted treatment yielded the lowest seed weight (33.42 g), reflecting the crucial role of phosphorus in grain filling and energy transfer. This result is in agreement with Noonari et al. (2016) who reported that application of P significantly increased 1000 seeds weight in wheat.\u003c/p\u003e\u003cp\u003eFuture studies could address several important factors. First, the interaction between wheat varieties and fertilization schemes, particularly in relation to nutrient uptake, warrants further investigation. Second, the role of water availability\u0026mdash;whether drought or irrigation\u0026mdash;in limiting wheat growth and constraining soil nitrogen mineralization and availability should be examined. Third, research could explore how variations in root architecture and soil microbial communities contribute to improved water and nutrient uptake. Beyond yield quantity, future studies should also evaluate the nutritional quality of wheat grains. While NP fertilization may increase yields, it is equally important that grains serve as a source of essential micronutrients for consumers. Future studies could therefore examine the contents of nutrients such as zinc, magnesium, and B-vitamins in the grains, linking this to broader issues of malnutrition and hidden hunger. Additionally, soil analyses for sulfur, potassium, zinc, and boron were not included in the present study, and should be incorporated in future work. Likewise, key parameters such as nutrient uptake, tissue nutrient concentrations, and nutrient use efficiency remain unaddressed and merit careful consideration in upcoming research. Finally, future studies should include baseline assessment of micronutrient levels as well as economic analyses of different blends. Such analyses would provide region-specific recommendations that are not only agronomically effective but also economically viable for growers and crop consultants.\u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eThe study demonstrated that nitrogen and phosphorus are the most limiting nutrients for wheat production in the study area. Their omission resulted in significant yield penalties, with nitrogen showing the most drastic effect. Other nutrients, including B, Zn, S, and K, did not significantly affect yield or yield components, suggesting sufficient baseline availability in the soil.\u003c/p\u003e\u003cp\u003eThe comparable performance of the NP and full nutrient treatments indicates that focusing on N and P is both agronomically sound and economically efficient for wheat production under the studied conditions. Fertilizer management in this region should focus primarily on nitrogen (N) and phosphorus (P) as the key inputs for wheat production. The application of micronutrients and secondary nutrients such as boron (B), zinc (Zn), sulfur (S), and potassium (K) should be based on site-specific soil test results or confirmed deficiency symptoms to prevent unnecessary expenditure on inputs.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding:\u003c/h2\u003e\n\u003cp\u003eThis research was funded by the Ethiopian Institute of Agricultural Research (EIAR).\u003c/p\u003e\n\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\n\u003cp\u003eA.A. analyzed the data and wrote the main manuscript text, prepared figures. M.T. assisted with conducting the field work and data collection. All authors reviewed and approved the final manuscript.\u003c/p\u003e\n\u003ch2\u003eAcknowledgement\u003c/h2\u003e\n\u003cp\u003eThe authors acknowledge the Ethiopian Institute of Agricultural Research (EIAR) for funding this study. We are also grateful to the experimental farmers for providing land and supporting the implementation of the field experiments.\u003c/p\u003e\n\u003ch2\u003eData Availability\u003c/h2\u003e\n\u003cp\u003eAll data generated or analyzed during this study are included in this published article.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbera, W., Tamene, L., Tesfaye, K., Jim\u0026eacute;nez, D., Dorado, H., Erkossa, T., \u003cem\u003eet al.\u003c/em\u003e A data-mining approach for developing site-specific fertilizer response functions across the wheat-growing environments in Ethiopia. \u003cem\u003eExp. Agric.\u003c/em\u003e \u003cstrong\u003e58\u003c/strong\u003e, e9 (2022).\u003c/li\u003e\n\u003cli\u003eBekele, T. \u0026amp; H\u0026ouml;fner, W. Effects of different phosphate fertilizers on yield of barley and rape seed on reddish brown soils of the Ethiopian highlands. \u003cem\u003eFertil. Res.\u003c/em\u003e \u003cstrong\u003e34\u003c/strong\u003e, 243\u0026ndash;250 (1993).\u003c/li\u003e\n\u003cli\u003eBouyoucos, G. J. Hydrometer method improved for making particle size analyses of soils. \u003cem\u003eAgron. J.\u003c/em\u003e \u003cstrong\u003e54\u003c/strong\u003e(5), 464\u0026ndash;465 (1962).\u003c/li\u003e\n\u003cli\u003eBrady, N. C. \u0026amp; Weil, R. R. \u003cem\u003eThe Nature and Properties of Soils\u003c/em\u003e (14th ed.). Prentice Hall (2008).\u003c/li\u003e\n\u003cli\u003eBremner, J. M. \u0026amp; Mulvaney, C. S. Nitrogen\u0026mdash;total. \u003cem\u003eMethods of Soil Analysis: Part 2. Chemical and Microbiological Properties\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e, 595\u0026ndash;624 (1982).\u003c/li\u003e\n\u003cli\u003eCSA. \u003cem\u003eAgricultural Sample Survey 2006\u0026ndash;07. Volume I\u003c/em\u003e. Addis Ababa (2007).\u003c/li\u003e\n\u003cli\u003eCurtin, D., Martin, R. J. \u0026amp; Scott, C. L. Wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e) response to micronutrients (Mn, Cu, Zn, B) in Canterbury, New Zealand. \u003cem\u003eN. Z. J. Crop Hortic. Sci.\u003c/em\u003e \u003cstrong\u003e36\u003c/strong\u003e(3), 169\u0026ndash;181 (2008). https://doi.org/10.1080/01140670809510233\u003c/li\u003e\n\u003cli\u003eFageria, N. K., Baligar, V. C. \u0026amp; Jones, C. A. \u003cem\u003eGrowth and Mineral Nutrition of Field Crops\u003c/em\u003e. CRC Press (2011).\u003c/li\u003e\n\u003cli\u003eGetinet, H., Abera, K. \u0026amp; Lulie, B. Identifying limiting nutrients for wheat production through omission plot experiment on Nitisols of East Gojjam Zone, North Western Ethiopia. \u003cem\u003eAm. J. Appl. Sci. Res.\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e(2), 49\u0026ndash;56 (2024).\u003c/li\u003e\n\u003cli\u003eGiraldo, P., Benavente, E., Manzano-Agugliaro, F. \u0026amp; Gimenez, E. Worldwide research trends on wheat and barley: A bibliometric comparative analysis. \u003cem\u003eAgronomy\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e(7), 352 (2019).\u003c/li\u003e\n\u003cli\u003eHodson, D. P., Jaleta, M., Tesfaye, K., Yirga, C., Beyene, H., Kilian, A., \u003cem\u003eet al.\u003c/em\u003e Ethiopia\u0026rsquo;s transforming wheat landscape: tracking variety use through DNA fingerprinting. \u003cem\u003eSci. Rep.\u003c/em\u003e \u003cstrong\u003e10\u003c/strong\u003e, 18532 (2020).\u003c/li\u003e\n\u003cli\u003eHuntley, B. J. Soil, Water and Nutrients. In \u003cem\u003eEcology of Angola\u003c/em\u003e. Springer, Cham (2023). https://doi.org/10.1007/978-3-031-18923-4_6\u003c/li\u003e\n\u003cli\u003eIFA, WFO \u0026amp; GACSA. \u003cem\u003eNutrient Management Handbook\u003c/em\u003e. 1st ed. (2016).\u003c/li\u003e\n\u003cli\u003eJewaro, H., Kefale, D. \u0026amp; Yoseph, T. Effects of blended fertilizer types and rates on growth, yield and yield component of bread wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) in Wondo district, southern Ethiopia. \u003cem\u003eInt. J. Agric. Innov. Res.\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e, 2319\u0026ndash;1473 (2020).\u003c/li\u003e\n\u003cli\u003eKihara, J., Nziguheba, G., Zingore, S., Coulibaly, A., Esilaba, A., Kabambe, V., \u003cem\u003eet al.\u003c/em\u003e Understanding variability in crop response to fertilizer and amendments in sub-Saharan Africa. \u003cem\u003eAgric. Ecosyst. Environ.\u003c/em\u003e \u003cstrong\u003e229\u003c/strong\u003e, 1\u0026ndash;12 (2016).\u003c/li\u003e\n\u003cli\u003eKumar, P., Shivay, Y. S. \u0026amp; Pooniya, V. Nutrient management for improving wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) productivity and soil fertility. \u003cem\u003eJ. Plant Nutr.\u003c/em\u003e \u003cstrong\u003e42\u003c/strong\u003e(12), 1439\u0026ndash;1456 (2019).\u003c/li\u003e\n\u003cli\u003eLal, R. Soil carbon sequestration impacts on global climate change and food security. \u003cem\u003eScience\u003c/em\u003e \u003cstrong\u003e304\u003c/strong\u003e(5677), 1623\u0026ndash;1627 (2004).\u003c/li\u003e\n\u003cli\u003eMoARD. \u003cem\u003eNational Fertilizer Strategy and Action Plan of Ethiopia\u003c/em\u003e. Addis Ababa, Ethiopia (2008).\u003c/li\u003e\n\u003cli\u003eNoonari, S., Kalhoro, S. A., Ali, A., Mahar, A., Raza, S., Ahmed, M., \u003cem\u003eet al.\u003c/em\u003e Effect of different levels of phosphorus and method of application on the growth and yield of wheat. \u003cem\u003eNat. Sci.\u003c/em\u003e \u003cstrong\u003e8\u003c/strong\u003e(7), 305\u0026ndash;314 (2016).\u003c/li\u003e\n\u003cli\u003eOlsen, S. R. Estimation of available phosphorus in soils by extraction with sodium bicarbonate. USDA Circular No. 939 (1954).\u003c/li\u003e\n\u003cli\u003eRichards, M. B., Butterbach-Bahl, K., Jat, M. L., Ort\u0026iacute;z Monasterio, J. I., Sapkota, T. B. \u0026amp; Lipinski, B. \u003cem\u003eSite-Specific Nutrient Management: Implementation Guidance for Policymakers and Investors\u003c/em\u003e (2015).\u003c/li\u003e\n\u003cli\u003eSebnie, W., Melak, E. \u0026amp; Lamesgn, H. Effects of nutrient omission on grain and biomass yield of irrigated wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e) in Sekota district, Amhara region, Ethiopia. \u003cem\u003eEnviron. Res. Commun.\u003c/em\u003e \u003cstrong\u003e6\u003c/strong\u003e(11), 115013 (2024).\u003c/li\u003e\n\u003cli\u003eSenbeta, A. F. \u0026amp; Worku, W. Ethiopia\u0026rsquo;s wheat production pathways to self-sufficiency through land area expansion, irrigation advance, and yield gap closure. \u003cem\u003eHeliyon\u003c/em\u003e \u003cstrong\u003e9\u003c/strong\u003e(10) (2023).\u003c/li\u003e\n\u003cli\u003eSolomon, W. \u0026amp; Anjulo, A. Response of bread wheat varieties to different levels of nitrogen at Doyogena, Southern Ethiopia. \u003cem\u003eInt. J. Sci. Res. Public.\u003c/em\u003e \u003cstrong\u003e7\u003c/strong\u003e(2), 452\u0026ndash;459 (2017).\u003c/li\u003e\n\u003cli\u003eTamene, L., Amede, T., Kihara, J., Tibebe, D. \u0026amp; Schulz, S. A review of soil fertility management and crop response to fertilizer application in Ethiopia: towards development of site- and context-specific fertilizer recommendation. Technical Report. CIAT, Addis Ababa, Ethiopia (2017).\u003c/li\u003e\n\u003cli\u003eTehulie, N. S. Response of bread wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) varieties to nitrogen fertilizer rates at Mekdela District, South Wollo, Ethiopia. \u003cem\u003eSci. Pap. Ser. A. Agron.\u003c/em\u003e \u003cstrong\u003e64\u003c/strong\u003e(2), 294\u0026ndash;302 (2021).\u003c/li\u003e\n\u003cli\u003eTimsina, J. \u0026amp; Connor, D. J. Productivity and management of rice\u0026ndash;wheat cropping systems: issues and challenges. \u003cem\u003eField Crops Res.\u003c/em\u003e \u003cstrong\u003e69\u003c/strong\u003e(2), 93\u0026ndash;132 (2001).\u003c/li\u003e\n\u003cli\u003eUllah, B., Lou, H., Arif, M., Zhang, S., Khan, H. A., Sadozai, K. N., \u003cem\u003eet al.\u003c/em\u003e Optimizing NPK fertilization for enhanced performance of Chinese wheat hybrids under agro-climatic condition of Peshawar Valley. \u003cem\u003eAgronomy\u003c/em\u003e \u003cstrong\u003e14\u003c/strong\u003e(9), 1904 (2024).\u003c/li\u003e\n\u003cli\u003eWalkley, A. \u0026amp; Black, I. A. An examination of the Degtjareff method for determining soil organic matter, and a proposed modification of the chromic acid titration method. \u003cem\u003eSoil Sci.\u003c/em\u003e \u003cstrong\u003e37\u003c/strong\u003e(1), 29\u0026ndash;38 (1934).\u003c/li\u003e\n\u003cli\u003eWogi, L., Dechassa, N., Haileselassie, B., Mekuria, F., Abebe, A. \u0026amp; Tamene, L. \u003cem\u003eA Guide to Standardized Methods of Analysis for Soil, Water, Plant, and Fertilizer Resources for Data Documentation and Sharing in Ethiopia\u003c/em\u003e. CIAT Publication No. 519. CIAT, Addis Ababa, Ethiopia, 41 p. (2021).\u003c/li\u003e\n\u003cli\u003eZingore, S., Delve, R. J., Nyamangara, J. \u0026amp; Giller, K. E. Multiple benefits of manure: the key to maintenance of soil fertility and restoration of depleted sandy soils on African smallholder farms. \u003cem\u003eNutr. Cycl. Agroecosyst.\u003c/em\u003e \u003cstrong\u003e80\u003c/strong\u003e, 267\u0026ndash;282 (2008).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Nutrient omission, Macro- and micronutrients, Fertilizer recommendation, Yield penalty","lastPublishedDoi":"10.21203/rs.3.rs-8012941/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8012941/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eLow wheat yields in Ethiopia are largely attributed to nutrient imbalances and blanket fertilizer use without site-specific recommendations. A field experiment was conducted across eight sites in Wera Dijo District, Halaba Zone, Central Ethiopia, during the 2021 cropping season to identify the most limiting nutrients for wheat (\u003cem\u003eTriticum aestivum\u003c/em\u003e L.) using nutrient omission trials. The study employed a randomized complete block design with ten treatments, omitting one nutrient at a time alongside complete, NP, and control treatments. Pre-treatment soil analyses showed slightly acidic to neutral pH (6.06\u0026ndash;6.99), medium to high organic carbon (1.85\u0026ndash;4.19%), and low to medium phosphorus (3.10\u0026ndash;10.94 mg/kg). Phosphorus deficiency was observed at seven of the eight sites. Nutrient treatments had a highly significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.0001) effect on yield and yield components. Omission of nitrogen and phosphorus markedly reduced yield, with nitrogen omission causing the greatest loss, indicating N as the most limiting nutrient. In contrast, omission of K, S, Zn, and B had no significant effect. Comparable yields from NP and complete treatments highlight the adequacy of site-specific N and P fertilization. These results emphasize the need for localized nutrient management to enhance wheat productivity and fertilizer efficiency in Halaba and similar agro-ecologies.\u003c/p\u003e","manuscriptTitle":"Identifying Limiting Nutrients for Wheat Production in Halaba, Central Ethiopia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-21 11:21:10","doi":"10.21203/rs.3.rs-8012941/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-12-06T04:23:54+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-04T08:39:09+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-04T02:58:57+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2025-12-01T21:49:43+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"181891517569681218870860731271837942434","date":"2025-11-17T08:48:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"212272178777338062041114400366016201975","date":"2025-11-16T14:56:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"216801382585361861751010663381179912162","date":"2025-11-14T07:40:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"234748661989353853698178310575179177468","date":"2025-11-13T16:35:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"100884223607427582343690381109138440616","date":"2025-11-13T06:24:47+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"249600349313783243547862834817524387084","date":"2025-11-11T22:35:57+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-11T14:37:32+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-06T14:29:17+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2025-11-06T07:54:23+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-11-04T23:14:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2025-11-04T23:11:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4b93b372-4a57-43b8-bcf7-6a88bddea120","owner":[],"postedDate":"November 21st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":58099705,"name":"Biological sciences/Ecology"},{"id":58099706,"name":"Earth and environmental sciences/Ecology"},{"id":58099707,"name":"Earth and environmental sciences/Environmental sciences"},{"id":58099708,"name":"Biological sciences/Plant sciences"}],"tags":[],"updatedAt":"2026-04-27T19:53:43+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-21 11:21:10","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8012941","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8012941","identity":"rs-8012941","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}