Physiological factors influencing climate-smart agriculture: Daylength-mediated interaction between tillering and flowering in rice

Physiological factors influencing climate-smart agriculture: Daylength-mediated interaction between tillering and flowering in rice | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Physiological factors influencing climate-smart agriculture: Daylength-mediated interaction between tillering and flowering in rice Hyeon-Seok Lee, Ju-Hee Kim, So-Hye Jo, Seo-Yeong Yang, Jae-Kyeong Baek, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5905758/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 31 Mar, 2025 Read the published version in BMC Plant Biology → Version 1 posted 4 You are reading this latest preprint version Abstract Introduction: Control of rice tillering and flowering is crucial for reducing greenhouse gas emissions from paddy fields, a key goal of climate-smart agriculture. However, the interaction between tillering and flowering is still debated and poorly understood. Methods We subjected plants of the rice cultivars ‘Saenuri’ and ‘Odae,’ to short- and long-day conditions after removing their tillers, and observed growth and flowering responses. Results and Discussion Different daylength conditions yielded contrasting results. Plants in tiller-removal groups grown under short days flowered early compared with that of the controls, whereas the opposite was observed under long days. Further, the expression of the florigen gene, Hd3a , promoting flowering, increased in the tiller-removal group under short days compared with that of the control. Conversely, the expression of the OsMFT1 gene, delaying flowering and increasing the number of spikelets per panicle, was upregulated under long days, and the phenotypic results were consistent. The number of spikelets per panicle in ‘Saenuri’ and ‘Odae’ plants in the tiller-removal groups under long day conditions increased approximately 3.4 and 2.2 times, respectively, compared with that of the corresponding control groups. Conclusion These findings reveal the daylength-dependent variability in tillering and flowering interactions, offering a novel perspective on their relationship. The results provide a foundation for developing climate-smart rice management practices and breeding strategies to optimize growth timing and enhance productivity under variable photoperiod conditions. climate-smart agriculture rice tillering flowering interaction Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Rice is a staple food for over half of the global population and plays a vital role in ensuring food security. However, methane emissions from paddy fields significantly contribute to greenhouse gas accumulation, making rice cultivation a major environmental challenge [ 1 , 2 ]. Methane production is primarily favored by waterlogged conditions [ 3 ], and its release occurs mainly through the aerenchyma tissues of rice tillers [ 4 ]. Shortening the growth period or modifying tillering patterns has been suggested as a potential strategy to mitigate methane emissions and promoting climate-smart rice production [ 4 , 5 , 6 ]. Daylength is a critical environmental factor that not only regulates flowering but also significantly influences tillering patterns [ 7 , 8 ]. Specifically, the optimum daylength for promoting tillering contrasts with the conditions required to accelerate flowering, creating a trade-off between vegetative and reproductive growth phases [ 9 , 10 ]. Despite extensive research, conflicting results have been reported regarding the interaction between tillering and flowering [ 11 , 12 , 13 ]. Molecular studies have highlighted the genetic and hormonal regulation of tillering and flowering, with implications for crop yield. Studies have identified hormonal and genetic regulators such as cytokinin, auxin, and strigolactone that mediate shoot branching and tillering [ 14 , 15 , 16 ]. Moreover, gene-editing approaches targeting key flowering regulators, including OsRFL and OsSOC1 , have shown that tillering and flowering exhibit complex, context-dependent interactions [ 17 , 18 ]. For instance, tillering increases under conditions of delayed flowering, as reported in studies involving the manipulation of key regulatory genes related to tillering [ 19 , 20 ]. Conversely, tillering decreases in some cases where flowering is delayed [ 21 , 22 ]. These conflicting results highlight the complexity of the interaction between tillering and flowering and underscore the need for further research to resolve discrepancies [ 23 , 24 , 25 , 26 , 27 ]. We hypothesized that this lack of consistency among research reports is due to the differences in plant development (e.g., tillering, spikelets formation, and flowering) that result from the specific daylength conditions used in different studies. Although the florigen activation complex (FAC) was found to affect growth phenomena such as tillering, in addition to flowering and floral induction [ 28 , 29 ], the interaction between tillering and flowering under specific daylength conditions has not been elucidated. In this study, we aim to elucidate the interaction between tillering and flowering responses by restricting tillering and growing two rice cultivars under controlled daylength conditions. The findings contribute to resolving inconsistencies in the literature and highlight the importance of photoperiod in designing climate-smart rice management practices. 2. Materials and methods 2.1 Ethics statement This study was performed in accordance with Institute-approved guidelines and regulations. The test varieties were provided by SeoYeong Yang of the Rice Production and Physiology Division of the National Institute of Crop science (NICS). We obtained permission from the NICS to use these varieties ( https://www.nics.go.kr/apo/breed.do?m=100000128&homepageSecod=nics ). 2.2 Experimental materials and design A pot experiment was conducted using a completely randomized design incorporating two factors of variation (daylength and tiller removal) at two levels of variation each (short and long day, and with and without tillers removed). Two experiments were conducted in a controlled environment facility (ENT Inc, Boocheon, Korea) at the National Institute of Crop Science in Jeonju, South Korea (35°49ʹ19ʺ N, 127°8ʹ56ʺ E), where light intensity, temperature, and humidity can be artificially controlled (Figure. S1). Lights were turned on at 0730 h regardless of daylength treatment, such that daylength was adjusted by the lights-off time. Two rice cultivars representing ecotypes with different maturation times were used, namely, early maturing ‘Odae’ ( Oryza sativa ssp. japonica , IT218242) and mid-late maturing ‘Saenuri’ ( Oryza sativa ssp. japonica , IT235281). Fifteen-day-old seedlings of both varieties were transplanted into 1/5000 a Wagner pots at a density of three plants per pot. A composite slow-release fertilizer was applied with 9, 4.5, and 5.7 kg nitrogen, phosphate, and potassium per 1000 m 2 , respectively, at a rate based on the area used by three plants (i.e., 0.042 m 2 ; planting distance: 30 × 14 cm) instead of the entire pot area. Tillers were removed every 2–3 d starting 7 d after transplanting, and water was continuously applied at a depth of 2–3 cm or more. A plant with tillers removed is shown in Figure S2. These procedures were performed as previously described [ 8 , 29 ]. 2.3 Experiment 1: Preliminary test of growth and heading responses to tiller removal under short-day conditions Temperature was set to 22°C (maximum 28°C/minimum 18°C) and daylength was fixed to relatively short conditions (12 h 30 min light/11 h 30 min dark) from sowing to the heading stage[ 30 , 31 , 32 ]. The light intensity was set at 700 µmol m − 2 s − 1 photosynthetically active radiation (PAR) and the relative humidity was set at 65% [ 33 ]. 2.4 Experiment 2: Analysis of growth and heading upon tiller removal under short- and long-day conditions Before tiller removal, the temperature was set to 28°C (maximum 33°C/minimum 23°C) for 22 d (15 d after sowing and 7 d after transplanting), and to minimize the induction of photosensitivity, daylength was set to 15 h [ 30 , 31 , 32 ], which is slightly longer than that generally used as a long-day condition (14 h 30 m light/9 h 30 m dark). The long-day condition was set before tiller removal to differentiate the photosensitive response to daylength conditions after tiller removal. Daylength conditions after tiller removal were matched between short (12 h light/12 h dark) and long (14 h 30 m light/9 h 30 m dark) days [ 30 , 31 , 32 ], and the temperature was set to 28°C (maximum 33°C/minimum 23°C). After the heading stage date, conditions were adjusted to 25°C (maximum 30°C/minimum 20°C) and long day (14 h light/10 h dark) during the ripening stage. Temperature and daylength were changed again after the ripening stage, as 28°C is deemed excessively high for the ripening stage, which could present challenges in accurately evaluating grain weight [ 34 ]. Additionally, different daylength conditions can affect grain weight; therefore, we set the same daylength condition again for the ripening stage. These conditions were set to observe the effect of temperature and daylength up to the heading stage. The light intensity was set at 700 µmol m − 2 s − 1 PAR and the relative humidity at 65%. 2.5 Growth and development measurements For the plant growth analysis, a total of 20 individual plants were analyzed as biological replicates. Plant height was measured from the ground to the top of the apical leaf tip. Stem length was measured from the ground to the uppermost internode. Leaf age is the leaf number formed on the main stem. Leaf age was calculated using the following equation: $$\:Leaf\:age=\left(n-1\right)+(m÷M)$$ where, n, M, and m are the total number of leaves, including incomplete leaves, length of the second fully expanded leaf from the top, and length of the unexpanded leaf derived from the second leaf sheath, respectively. Leaf age is used as an indirect indicator to assess the transition among growth stages [ 8 ]. In both experiments, the heading date was calculated as the number of days (growth period) after transplanting, before panicle emergence from the leaf sheath. Panicle emergence was examined daily from 1300–1400 hrs. Fifteen plants were used to analyze heading date and growth. These procedures were performed as previously described [ 8 ]. 2.6 RNA extraction and gene expression For RNA expression analysis, three individual plants were used with two leaves collected from each plant. Each leaf sample was further analyzed in triplicated technical replicates. Two plant leaves were sampled, namely the 2nd and 3rd leaves of the main stem and tiller, immediately frozen under liquid nitrogen, and stored at -80°C until RNA extraction. The sampling of the 2nd and 3 rd leaves has a more relatively stable physiological response because the 1st is a leaf that is still developing. Three biological replicates per treatment, with each replicate comprising three plants. For each plant, the 2nd and 3rd leaves were sampled and utilized for real-time polymerase chain reaction (RT-PCR). Technical replicates were performed thrice per biological replicate to ensure statistical robustness and accuracy. Plant material for RNA extraction was sampled at 1000 hrs. (2.5 h after lights were turned on) because Hd3a, RFT1, Ehd1, Ghd7 , and MFT1 reportedly maintain a high expression level for 0–4 h after plant exposure to light [ 35 ]. Total RNA was extracted according to the protocol by Chang et al., [ 36 ]. cDNA synthesis was performed using a Primescript RT reagent kit with gDNA eraser (TaKaRa Bio, Inc, Kusatsu, Japan). For RT-PCR, SYBR Green (SYBR Realtime PCR Master Mix, Toyobo, Japan) was used as a fluorescent dye. The analysis was conducted using a Roter-Gene 6000 (Corbett Research, Australia). All experiments were performed in triplicate. Relative expression values were calculated using the reference gene ubiquitin for comparison of Ct values. These values were then normalized to a baseline of 1.0, with the sample collected 1 day prior to the day-length, and tiller removal treatments were used as the reference. Primer sequences are listed in Table S1 . The procedures were performed as previously described [ 8 ]. 2.7 Statistical analysis Statistical analysis was performed using R software (version 4.0.3, R Foundation, Austria). Significant differences were assessed at p < 0.05 using a one-sample t-test and ANOVA, followed by Duncan's multiple range test. Before statistical analyses, Levene’s test and the Shapiro-Wilk test were performed to assess the homogeneity of variance and normality of the data, respectively. When the assumptions of homogeneity or normality were not met, non-parametric tests, such as the Kruskal-Wallis test, were employed as they are more suitable for small sample sizes (n = 9 for RNA expression). Parametric tests, such as ANOVA were applied if the assumptions were met. This approach allowed us to rigorously assess the effects of high temperature and ozone on plant growth and physiological responses, including dry weight, plant height, leaf age, stomatal conductance, and stress-related gene expression, both before and after the treatments. Eq. ( 1 ) [ 37 ] was used to model the development of plant height, leaf age, and tiller number based on the number of growing days from transplanting: $$\:F=\frac{{H}_{max}\:or\:{L}_{max}\:or\:{T}_{max}\:}{1+{e}^{-\left(t-tm\right)\text{*}rF}}$$ 1 where, H max , L max , T max , r F, t , and tm are the final plant height, final leaf age, final number of tillers, rate of development up to final plant height, leaf age, or tiller number, the number of days after transplanting, and timepoint at which half of the final plant height or leaf age or tiller number was achieved, each referring to the timepoint when plant height, leaves, or tillers reached the maximum rate of development, respectively. Successively, H max , L max , T max , r F , and tm are coefficients determined by nonlinear regression analysis performed using Sigmaplot v11.1. These procedures were performed as previously described [ 8 ]. 3. Results 3.1 Daylength-mediated effects of tiller removal on plant growth and development This study examined main stem growth and development, with and without tillers, under varying daylength conditions. The data showed that under long days, plant height ( H max ) in the tiller-removal treatment (TR) group exhibited a trend of increase in both cultivars compared to the control group. However, under short days, which are known to promote flowering [ 8 ], H max decreased in the TR group for ‘Saenuri’ but remained unchanged for ‘Odae’ (Fig. 1 a, b; Table 1 ). Under short days, H max in the TR and control groups was 89.9 cm and 89.8 cm for ‘Odae,’ and 72.4 cm and 75.3 cm for ‘Saenuri,’ respectively. Furthermore Under long days, the rate of increase in plant height ( r F ) was lower in the TR group compared to the control. However, the period of increase ( t m ) in plant height was longer in the TR group (Fig. 1 a,b; Table 1 ). However, under short days, r F was higher in the TR than in the control group; concomitantly, tm was shorter for ‘Saenuri,’ whereas in ‘Odae,’ it differed slightly compared with that observed under long days. Meanwhile, Lmax of the main stem was higher in the TR group than that in the control for both varieties across the experimental conditions (Fig. 1 c,d; Table 1 ). Evidently, under SD conditions, it was slightly lower in the TR in both cultivars; however, it differed between the two cultivars under long days (Fig. 1 c,d; Table 1 ). In contrast, tm was longer in the TR groups under all conditions for both cultivars (Fig. 1 c,d; Table 1 ). Under SD conditions, 'Odae' exhibited a slight increase in Lmax from 13.0 to 13.6 under TR group, with tm extending from 5.6 to 7.0 days. Conversely, under LD conditions, Lmax increased more significantly from 14.2 to 17.1, and tm extended from 9.3 to 14.5 days (Fig. 1 c,d; Table 1 ). For 'Saenuri,' Lmax similarly increased from 13.1 to 13.8 in the SD TR treatment, with tm slightly increasing from 6.2 to 6.4 days. Under LD conditions, Lmax increased from 16.9 to 18.6, and tm extended from 14.3 to 16.0 days (Fig. 1 c,d; Table 1 ). rF declined under LD conditions compared to SD in both cultivars, with 'Odae' showing a reduction from 0.081 to 0.066 and 'Saenuri' from 0.090 to 0.054 in the control treatments. Interestingly, rF remained consistent or slightly increased under the TR treatments, suggesting that tiller removal may have mitigated the impact of LD on leaf development. Additionally, Tmax was lower under short than under long days for both cultivars (Fig. 1 e,f; Table 1 ). Differences in growth at the heading stage, i.e., after vegetative growth was completed, in response to tiller removal as per daylength are shown in Fig. 2 . Similar to the results described for plant height (Fig. 1 a,b), stem length was greater in the tiller removal than that in the control group under long days, whereas no difference was observed under short days (Fig. 2 a,b). Panicle length was only slightly greater in the tiller removal treatment under short days but showed a substantial increase under long days (Fig. 2 c,d). Overall, the TR treatment increased vegetative growth of the main stem under long days; however, under short days, growth was either smaller or did not significantly differ between the TR and control treatments (Fig. 1 , 2 ; Table 1 ). Table 1 Parameters of the logistic function used to describe plant height, leaf age, and tiller development from sowing to heading stage date after transplanting for the tiller removal treatments according to daylength. Varieties Treatment Plant height (cm) Leaf age (ea) Tiller number (ea) H max † r F †† t m ††† R 2 L max † r F t m R 2 T max † r F t m R 2 ‘Odae’ SD Control 89.8 (1.74) 0.078 (0.007) 7.2 (0.89) 0.98 13.0 (0.14) 0.081 (0.005) 5.6 (0.51) 0.99 15.1 (0.49) 0.232 (0.051) 15.7 (1.04) 0.96 Tiller X 89.9 (1.71) 0.082 (0.007) 8.3 (0.86) 0.98 13.6 (0.19) 0.079 (0.005) 7.0 (0.65) 0.99 - - - - LD Control 91.0 (3.89) 0.057 (0.008) 9.7 (1.90) 0.97 14.2 (0.17) 0.066 (0.003) 9.3 (0.54) 0.99 19.9 (0.47) 0.294 (0.056) 16.2 (0.66) 0.98 Tiller X 108.3 (4.29) 0.054 (0.006) 15.4 (1.84) 0.98 17.1 (0.21) 0.058 (0.002) 14.5 (0.54) 0.99 - - - - ‘Saenuri’ SD Control 75.3 (1.27) 0.081 (0.008) 8.1 (1.06) 0.97 13.1 (0.10) 0.090 (0.005) 6.2 (0.52) 0.99 15.7 (0.23) 0.239 (0.029) 14.6 (0.56) 0.98 Tiller X 72.4 (1.03) 0.084 (0.008) 6.4 (0.94) 0.97 13.8 (0.13) 0.089 (0.006) 6.4 (0.63) 0.98 - - - - LD Control 86.4 (1.89) 0.053 (0.004) 13.8 (1.25) 0.98 16.9 (0.23) 0.054 (0.003) 14.3 (0.79) 0.99 19.9 (0.77) 0.324 (0.123) 16.2 (1.21) 0.91 Tiller X 107.0 (4.41) 0.046 (0.005) 22.6 (2.41) 0.98 18.6 (0.17) 0.058 (0.002) 16.0 (0.54) 0.99 - - - - SD: short day, LD: long day. Tiller X refers to the TR treatment. † Hmax is the final plant height, Lmax is the final leaf age from the main stem, and Tmax is the final number of tillers. †† rF is the rate of development up to the final plant height, leaf age, and tiller number. ††† t is the number of days after transplantation; tm is the time point at which the plant reached half of its final height, leaf age, and tiller number. ** P < 0.01. 3.2 Effect of tiller removal on heading response and yield components When other relevant factors, such as fertilization, are controlled, tiller development is generally enhanced as a result of the longer growth duration [ 10 , 11 , 13 ]. Under the short-day conditions used in Experiment 1, days to heading (DTH) was shortened in the TR compared with that in the control treatment group for both cultivars (Figure S3). Further, in Experiment 2, we evaluated DTH under two daylength conditions (Fig. 3 ) and found that under short days, DTH was shortened in the TR compared with that in the control group, similar to that of the results of Experiment 1. Conversely, DTH was longer in the TR than that in the control group under long days (Fig. 3 ). Under SD conditions, TR reduced the heading date by 3 days in both ‘Odae’ and ‘Saenuri.’ In contrast, under LD conditions, TR delayed the heading date by 5 days in ‘Odae’ and approximately 2 days in ‘Saenuri.’. The ANOVA revealed that no significant difference was observed in DTH due to TR, although it showed a highly significant difference as a result of the interaction between daylength and TR (Table S3). Among yield components, spikelet number per panicle (SPP) showed the largest change associated with TR and daylength treatments (Table 2 ). Particularly, SPP was lower under short than under long days for both control and TR groups (Table 2 ). Additionally, SPP showed a greater daylength-mediated variation in the TR than that in the control group (Table 2 ). Furthermore, in the ‘Saenuri’ cultivar, SPP was the lowest (62.2) and highest (235.0) in the TR group under short and long days, respectively, with a 3.78-fold difference between the two extreme values (Table 2 ). The proportion of ripened grain slightly decreased in the TR treatment, particularly under short days, in which case SPP actually increased significantly (Table 2 ). Further, 1000-grain weight did not significantly differ between the experimental groups for either cultivar (Table 2 ). Similar results were found for Experiment 1 (Table S2). Table 2 Changes in yield components upon tiller removal according to daylength from sowing to heading stage date. Varieties Treatment Panicle number (ea) Spikelet number per panicle (ea) Ripened Grain (%)††† 1000- Grain weight (g)††† ‘Odae’ SD Control 13.0a 56.9c 95.6a 28.1a Tiller X 1.0b 74.1b 84.3b 28.1a LD Control 13.5a 58.2c 95.6a 28.4a Tiller X 1.0b 127.1a 78.5c 28.4a ‘Saenuri’ SD Control 13.8a 62.2b 93.8a 28.9a Tiller X 1.0b 59.3b 72.6c 30.3a LD Control 14.0a 69.1b 89.7a 28.0a Tiller X 1.0b 235.0a 79.7b 28.3a Analysis of variance (ANOVA) Variety (V) ns *** *** ns Daylength (D) ns *** ns ns Tiller (R) *** *** ** ns Interaction (V*D) ns *** ns ns Interaction (V*R) ns *** *** ns Interaction (D*R) ns *** *** ns Interaction (V*D*R) ns *** *** ns SD: short day, LD: long day. Tiller X refers to the TR (tiller removal) treatment. ns: non-significant (P ≥ 0.05), *, **, ***: significant at P < 0.05, 0.01, and 0.001. Letters indicate significant differences (P < 0.05). † Number of days from sowing to heading date (main stem). †† Final leaf age from the main stem; final tiller number was the highest up to the heading date. 3.3 Florigen- and spikelet formation-related gene expression Florigen gene Hd3a- expression levels significantly increased under short than under long days at 3 and 7 d after treatment (DAT, Fig. 2 a). At 7 DAT under short days, Hd3a levels were 102.4, 79.0, and 75.8 in the main stem of the treatment (TMS), control (CMS), and tillers of the control (CT, Fig. 4 a) groups, respectively. Additionally, the expression of Hd3a in the main stem of the TR group tended to increase under short days and increased over time after TR treatment. However, under long days, Hd3a expression decreased compared with that of its level before daylength treatment, with no discernible difference between TR groups. The MOTHER OF FT AND TFL1 (MFT1) gene reportedly increases SPP and is associated with delayed flowering [ 38 ]. Similar to that of the heading and SPP responses induced by daylength and TR treatments, MFT1 expression differed considerably between daylength conditions. Particularly, the MFT1 expression level was higher in the CMS and CT than that in the TMS groups under short days (Fig. 4 b); however, the opposite trend was observed under long days (Fig. 4 b). At 7 DAT under short-day conditions, the expression of Hd3a relative to MFT1 ( Hd3a/MFT1 ) increased under the TR treatments, with values of 13.8, 8.6, and 7.4 for TMS, CMS, and CT, respectively. Contrastingly, at 3 DAT under long-day conditions, the expression of Hd3a relative to MFT1 decreased under the TR treatments, with values of 0.2, 0.5, and 0.5 for TMS, CMS, and CT, respectively (Fig. 4 c). These results indicate that the expression levels of the two genes vary depending on daylength conditions Other flowering-related genes were analyzed together (Figure S4). Therefore, for example, RFT1 , which is another florigen gene controlling flowering under short and long days [ 32 ] showed relative expression levels of 61.1, 55.5, and 55.1 in the TMS, CMS, and CT groups, respectively, under short days (Figure S4a). Similarly, the relative expression levels of Ehd1 , which enhances the expression of Hd3a and RFT1 under short-day conditions [ 10 ], were 20.1, 19.2, and 14.7 in the TMS, CMS, and CT groups, respectively (Figure S4b). Simultaneously, the relative expression levels of Ghd7 under long days, which suppresses the expression of Hd3a and RFT1 under such conditions [ 32 ], were 1.9, 1.7, and 1.4 in the TMS, CMS, and CT groups, respectively (Figure S4c). 4. Discussion Rice is grown over a wide range of latitudes globally; therefore, the plant grows under different daylength conditions depending on the specific location, ranging from approximately 12 h in low-latitude regions to 13–14.5 h in high-latitude regions [ 8 , 26 , 27 ]. Even within the same region, it will grow under different daylength conditions depending on climate change or planting season [ 39 ]. Tillering is greatly affected by temperature and daylength [ 24 ]. Generally, short days and high temperature lead to earlier flowering as a result of the restriction of tillering imposed by the shortened vegetative growth period [ 27 , 40 ]. However, currently, the interaction between tillering and flowering has not been fully elucidated and in fact remains a controversial issue. Floral induction is essential for flowering [ 31 , 32 ], and as it initiates a shift toward reproductive growth, it serves as a key regulator of the vegetative growth period [ 41 – 42 ]. Further, because tillering mainly occurs during the vegetative growth period, it is strongly influenced by developmental processes such as floral induction [ 43 ]. Specifically, FLOWERING LOCUS C (FLC) and FRIGIDA (FRI), two floral repressors in the vernalization pathway, reportedly regulate tillering in Arabidopsis thaliana [ 43 , 44 ] and similar related studies were reported in other species [ 45 , 46 ]. Since the initial discovery of the MOC1 gene as a crucial regulator of rice tillering, several studies were conducted at both physiological and molecular levels [ 47 , 48 ]. Therefore, for example, the correlation between vegetative growth (e.g., tiller and leaf development depending on nitrogen supply) and flowering time was investigated [ 24 , 47 ]. Several studies reported a negative relationship between tillering and flowering [ 13 , 14 , 23 , 27 ]. The FAC is a structure in which Hd3a binds to 14-3-3 proteins acting as intracellular receptors, and OsFD , a transcription factor in the bzip region, is attached to this complex and promotes floral induction [ 28 ]. These FACs activate OsMADS 14 and 15 , genes located downstream from Hd3a promoting floral formation and development [ 28 ]. However, other OsFD- like transcription factors bound to FAC participate in lateral branching in the axillary meristem [ 20 ] and leaf development [ 49 ]. Therefore, Hd3a promotes lateral branching in the axillary meristem and leaf development over floral induction [ 28 ]. Additionally, OsLUX -overexpressing mutants show reduced photoperiod sensitivity and a prolonged juvenile phase, which successively results in an increased number of tillers and delayed heading [ 19 ]. However, tillering and flowering were reported to be positively correlated [ 22 , 50 ]. The number of tillers reportedly increases with flowering induced by the overexpression of OsRFL , which regulates the flowering activator OsSOC1 . Conversely, RFL knockdown results in the restriction of development of secondary tillers and panicle branches, and delay in flowering [ 22 ]. Similarly, when the expression of OsWDRa or OsTRx1 of the COMPASS-like complex was reduced by RNA interference under long and short days, secondary branches and grain number decreased concomitant with delayed heading [ 50 ]. Here, we found that these contrasting results may be influenced by daylength (Fig. 5 ). The data showed that, when tillers were removed, the heading stage was reached earlier under short days, whereas it was delayed under long days (Fig. 3 , S3). Similar results were observed when tiller development was restricted [ 28 ]. It is likely that, in conjunction with the FAC complex, Hd3a may promote floral induction rather than lateral branching in the axillary meristem under conditions of restricted tiller development [ 28 ]. Based on this hypothesis, we analyzed the florigen Hd3a in the main stem and tiller under each of these treatment conditions (Fig. 4 a). We observed that under short days the relative expression levels of the florigen genes increased with treatment time. Furthermore, under short days the relative expression levels of both florigens ( Hd3a and RFT1 ) in the main stem, from which the tillers were removed, increased compared to those in the control (Fig. 4 a, S4a). This change in gene expression may provide a novel insight into the early heading stage transition after tiller removal under short days. Under SD conditions, differences in H max responses to TR were observed between ‘Saenuri’ and ‘Odae.’ Specifically, H max decreased in the TR group for ‘Saenuri’ but remained unchanged for ‘Odae’ (Fig. 1 a, b). These differences suggest cultivar-specific responses to photoperiod and tiller removal. While these findings highlight distinct responses between the cultivars, we did not conduct detailed analyses of the genetic or physiological mechanisms underlying these differences. Further research is needed to investigate the genetic regulation or physiological traits driving these contrasting responses. Meanwhile, Hd3a had a less prominent role under long than that under short days, whereas SPP increased markedly in the TR group under long days (Table 2 ). For cultivar ‘Saenuri’ under short days, SPP of the TR group (59.3) was less than that of the control group (62.2); however, under long days, SPP for the TR group (235) was 3.4 times greater than that of the control group (69.1) (Table 2 ). Generally, the heading date is delayed in situations of expanding quantitative growth, such as an increase in SPP due to excessive nitrogen supply [ 51 ]. To interpret these results, we analyzed the expression of the MFT1 gene under each treatment, given its role in the formation of spikelets and branches while suppressing flowering [ 38 ]. In contrast to short-day conditions, the expression of MFT1 in CMS and CT groups decreased compared to that in the TMS groups under long days (Fig. 4 b). Further, the SPP of TMS groups increased under long days (Table 2 ). Therefore, the phenotype of rice plants, including heading date and SPP, corresponded to the expression of MFT1 . Summarily, under short-day conditions, in which case floral induction is optimal, Hd3a may play a more prominent role in floral induction of the main stem than that in tillering (i.e., lateral bud formation) in the TR treatment; thus, the time required to reach the heading stage may be shortened (Fig. 3 ). Contrastingly, the difference in SPP between TR and control groups under long days was significantly greater than that under short days. Additionally, the characteristics of the expression of the related gene, MFT1 , also showed the same pattern; specifically, MFT1 expression significantly increased in the TR group than that in the control group only under long days. Furthermore, the expression levels of MFT1 showed the opposite pattern to those of Hd3a and RFT1 under short days (Fig. 4 ; FigureS4). Simultaneously, the larger increase in SPP in the TR treatment was the primary factor contributing to the observed delay in flowering under long days, which is in contrast to that of the results obtained under short days. 5. Conclusions Our findings highlight the need for climate-smart crop production schemes to address the challenges of optimizing rice growth and productivity under variable daylength conditions. Our study revealed that under LD conditions, reduced tillering increased vegetative growth and delayed days to heading, while under SD conditions, reduced tillering shortened days to heading. These physiological traits could be used to optimise the timing of growth and carbon emissions in rice production. And our study clarified that the variability in tillering and flowering, often associated with conflicting results in previous research, is strongly influenced by daylength. Furthermore, Our findings suggest a novel approach to breeding and management practices by targeting daylength-dependent interactions between rice tillering and flowering, thereby improving adaptability to climate change. Declarations Conflict of Interest The authors declare no conflicts of interest. Author Contributions H.S.L. and J.Y.S. conceived and supervised the project. H.S.L. designed the experiments. H.S.L. and J.H.K. conducted the gene expression analysis and field experiments. H.S.L, S.Y.Y, S.H.J, and J.K.B. analyzed the data and drafted the manuscript. All authors discussed the results and contributed to the paper. Funding This work was supported by the Rural Development Administration National Research Project (Project Name: Investigation of metabolic mechanism controlling thermoresponsive flowering time at high temperature), Project No. PJ01486003. Acknowledgments We thank Editage for English language editing. 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Supplementary Files SupportingInformationvFFFF.docx Supplementary Materials: Figures S1: Architecture of a ‘Saenuri’ rice plant; Figure S2: Number of growing days from sowing to heading stage in the two rice cultivars for control and tiller removal treatments; Figure S3: Changes in (a) RFT1, (b) Ehd1, and (c) Ghd7 mean relative expression levels in ‘Saenuri’ rice plants for the tiller removal treatment under contrasting daylength conditions; Table S1: List of primer sequences of Oryza sativa used for qRT-PCR; Table S2: Changes in rice plant growth and development traits after tiller removal; Table S3: Analysis of variance (ANOVA) for growth duration, stem length, and panicle length caused by tiller removal under contrasting daylength conditions. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5905758","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":409576374,"identity":"83425d40-e5d4-4daa-8d5f-26ac867dcb35","order_by":0,"name":"Hyeon-Seok Lee","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA7ElEQVRIiWNgGAWjYLACCQYJHn725sMQHg9hDYwNEgwWcpI9x5JJ0MLAUGFscCPHmDgt8hHpzx9Y7pFIbLiR89ng4x4beQaesw/wajG8kWPYIPFMIrGx5+3mxBnP0gwbeNsN8GuZkQP0ywGJxGb23M2HeQ4cZmzgZ8PvMMMZ6Q/BWtoYch4Dtfy3J6hFXiLBEKTFmIcjhzmZ58CBxAbeNvxaDHjeGM4AapGT4DlmbDjjQHJyG88xAra0pz/4LHGgjsf+ePNjiQ8H7Gz7edII2HKAgYFZAlmEgE+AtjQA4/IDIVWjYBSMglEwsgEA9jJHZcqY+uMAAAAASUVORK5CYII=","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":true,"prefix":"","firstName":"Hyeon-Seok","middleName":"","lastName":"Lee","suffix":""},{"id":409576375,"identity":"e2f5eeb5-0ef4-41ea-b15d-15223c28ed4b","order_by":1,"name":"Ju-Hee Kim","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Ju-Hee","middleName":"","lastName":"Kim","suffix":""},{"id":409576377,"identity":"1599c1c1-63b4-4b9c-be77-9b773a6b2fcb","order_by":2,"name":"So-Hye Jo","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"So-Hye","middleName":"","lastName":"Jo","suffix":""},{"id":409576378,"identity":"8f8181fa-8618-481c-ba29-54cd45e7f551","order_by":3,"name":"Seo-Yeong Yang","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Seo-Yeong","middleName":"","lastName":"Yang","suffix":""},{"id":409576379,"identity":"297215a4-c7d0-4157-9f37-38ccac46b991","order_by":4,"name":"Jae-Kyeong Baek","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Jae-Kyeong","middleName":"","lastName":"Baek","suffix":""},{"id":409576381,"identity":"fd2b764e-3a2a-4b4d-a426-918c9c8e68ab","order_by":5,"name":"Yeong-Seo Song","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Yeong-Seo","middleName":"","lastName":"Song","suffix":""},{"id":409576383,"identity":"3170267a-ec6f-4631-8128-631242729b85","order_by":6,"name":"Jiyoung Shon","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Jiyoung","middleName":"","lastName":"Shon","suffix":""},{"id":409576386,"identity":"369d0302-278b-4dfd-a23c-cc28f38ac776","order_by":7,"name":"Jeong-Il Cho","email":"","orcid":"","institution":"National Institute of Crop Science, Rural Development Administration","correspondingAuthor":false,"prefix":"","firstName":"Jeong-Il","middleName":"","lastName":"Cho","suffix":""}],"badges":[],"createdAt":"2025-01-26 10:08:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5905758/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5905758/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s12870-025-06430-z","type":"published","date":"2025-03-31T15:57:31+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":75401991,"identity":"96d91e9e-6f15-48a6-8a92-a8e2b8ecec6f","added_by":"auto","created_at":"2025-02-04 08:07:25","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":39875,"visible":true,"origin":"","legend":"\u003cp\u003eLogistic model of rice plant height, leaf age, and tiller development from sowing to heading stage date after transplant for tiller removal treatments according to daylength. (a) ‘Odae,’ plant height; (b) ‘Saenuri,’ plant height; (c) ‘Odae,’ leaf age; (d) ‘Saenuri,’ leaf age; (e) ‘Odae,’ tiller number; (f) ‘Saenuri,’ tiller number. SD: short day. LD: long day. Tiller X refers to tiller removal (TR) treatment. Curves were fitted to a logistic equation, as in Table 1. Growth data collected from 20 biological replicates for each treatment (n=20).\u003c/p\u003e","description":"","filename":"OnlineFigure1.png","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/ccea098545b1ce20fc2dab36.png"},{"id":75401992,"identity":"cf4455b1-4206-4b6f-ab28-4c1176a8f84e","added_by":"auto","created_at":"2025-02-04 08:07:25","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":18826,"visible":true,"origin":"","legend":"\u003cp\u003eBoxplot graph of the differences in growth with tiller removal and daylength conditions at heading date. (a) ‘Odae, stem length; (b) ‘Saenuri, stem length; (c) ‘Odae’ panicle length; (d) ‘Saenuri panicle length. SD: short day. LD: long day. Tiller X refers to tiller removal treatment. Letters above bars indicate significant differences (P \u0026lt; 0.05) according to Duncan’s multiple range test. Growth data collected from 20 biological replicates for each treatment (n=20).\u003c/p\u003e","description":"","filename":"OnlineFigure2.png","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/d56e0345f0de5979a7b25f56.png"},{"id":75402857,"identity":"257ebdb2-85b7-47bb-a75f-b34d33d20c6a","added_by":"auto","created_at":"2025-02-04 08:15:26","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":17973,"visible":true,"origin":"","legend":"\u003cp\u003eBoxplot graph of days to heading upon tiller removal and under contrasting daylength conditions. (\u003cstrong\u003ea\u003c/strong\u003e) ‘Odae,’ (\u003cstrong\u003eb\u003c/strong\u003e) ‘Saenuri.’ SD: short day. LD: long day. Tiller X refers to tiller removal treatment. Days to heading data collected from 20 biological replicates for each treatment (n=20). Letters above bars indicate significant differences (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) according to Duncan’s multiple range test.\u003c/p\u003e","description":"","filename":"OnlineFigure3.png","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/3aef2b762b7bc51e8ff7a9cf.png"},{"id":75401997,"identity":"c9c5dea2-954c-4d2c-a951-4f4712df8f96","added_by":"auto","created_at":"2025-02-04 08:07:25","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":76779,"visible":true,"origin":"","legend":"\u003cp\u003eChanges in (\u003cstrong\u003ea\u003c/strong\u003e) \u003cem\u003eHd3a\u003c/em\u003e, (\u003cstrong\u003eb\u003c/strong\u003e) \u003cem\u003eMFT1\u003c/em\u003e, and (c) \u003cem\u003eHd3a/MFT1\u003c/em\u003e mean relative expression levels in ‘Saenuri’ rice plants in the tiller removal treatment groups according to daylength conditions, compared with that of the relative expression level before treatment (standard). TMS: tiller removal main stem. CMS: control rice plant-main stem. CT: control rice plant-tiller. DAT: days after treatment. SD: short day. LD: long day. Values represent the mean of three biological replicates (n=3), each analyzed in triplicate technical replicates. Letters above bars indicate significant differences (\u003cem\u003eP\u003c/em\u003e \u0026lt; 0.05) according to Duncan’s multiple range test. “ns” indicates non-significant (\u003cem\u003eP ≥\u003c/em\u003e 0.05). Vertical lines on bars represent SE (n=9).\u003c/p\u003e","description":"","filename":"OnlineFigure4.png","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/5f182e8d21e8c22b5d785e8c.png"},{"id":75402858,"identity":"c1351826-53bb-4fae-9051-1059017a79a1","added_by":"auto","created_at":"2025-02-04 08:15:26","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":641187,"visible":true,"origin":"","legend":"\u003cp\u003eChanges in plant growth and phenology responses to daylength conditions and tiller removal.\u003c/p\u003e","description":"","filename":"Figure52.png","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/c1356336eed000020d4f9f07.png"},{"id":80082246,"identity":"f3d60890-892b-4c13-b1f8-4ba1e856fa40","added_by":"auto","created_at":"2025-04-07 16:07:55","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2063896,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/a42013b0-3740-424e-b6eb-d39ce159e7c8.pdf"},{"id":75402000,"identity":"18e41f44-ce5c-4aee-843a-99c2e4a81399","added_by":"auto","created_at":"2025-02-04 08:07:26","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":4136731,"visible":true,"origin":"","legend":"\u003cp\u003eSupplementary Materials: Figures S1: Architecture of a ‘Saenuri’ rice plant; Figure S2: Number of growing days from sowing to heading stage in the two rice cultivars for control and tiller removal treatments; Figure S3: Changes in (a) RFT1, (b) Ehd1, and (c) Ghd7 mean relative expression levels in ‘Saenuri’ rice plants for the tiller removal treatment under contrasting daylength conditions; Table S1: List of primer sequences of Oryza sativa used for qRT-PCR; Table S2: Changes in rice plant growth and development traits after tiller removal; Table S3: Analysis of variance (ANOVA) for growth duration, stem length, and panicle length caused by tiller removal under contrasting daylength conditions.\u003c/p\u003e","description":"","filename":"SupportingInformationvFFFF.docx","url":"https://assets-eu.researchsquare.com/files/rs-5905758/v1/f19f0762aef66150f083ba68.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Physiological factors influencing climate-smart agriculture: Daylength-mediated interaction between tillering and flowering in rice","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eRice is a staple food for over half of the global population and plays a vital role in ensuring food security. However, methane emissions from paddy fields significantly contribute to greenhouse gas accumulation, making rice cultivation a major environmental challenge [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Methane production is primarily favored by waterlogged conditions [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], and its release occurs mainly through the aerenchyma tissues of rice tillers [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Shortening the growth period or modifying tillering patterns has been suggested as a potential strategy to mitigate methane emissions and promoting climate-smart rice production [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDaylength is a critical environmental factor that not only regulates flowering but also significantly influences tillering patterns [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Specifically, the optimum daylength for promoting tillering contrasts with the conditions required to accelerate flowering, creating a trade-off between vegetative and reproductive growth phases [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Despite extensive research, conflicting results have been reported regarding the interaction between tillering and flowering [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eMolecular studies have highlighted the genetic and hormonal regulation of tillering and flowering, with implications for crop yield. Studies have identified hormonal and genetic regulators such as cytokinin, auxin, and strigolactone that mediate shoot branching and tillering [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e, \u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Moreover, gene-editing approaches targeting key flowering regulators, including \u003cem\u003eOsRFL\u003c/em\u003e and \u003cem\u003eOsSOC1\u003c/em\u003e, have shown that tillering and flowering exhibit complex, context-dependent interactions [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. For instance, tillering increases under conditions of delayed flowering, as reported in studies involving the manipulation of key regulatory genes related to tillering [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Conversely, tillering decreases in some cases where flowering is delayed [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. These conflicting results highlight the complexity of the interaction between tillering and flowering and underscore the need for further research to resolve discrepancies [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eWe hypothesized that this lack of consistency among research reports is due to the differences in plant development (e.g., tillering, spikelets formation, and flowering) that result from the specific daylength conditions used in different studies. Although the florigen activation complex (FAC) was found to affect growth phenomena such as tillering, in addition to flowering and floral induction [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e], the interaction between tillering and flowering under specific daylength conditions has not been elucidated.\u003c/p\u003e \u003cp\u003eIn this study, we aim to elucidate the interaction between tillering and flowering responses by restricting tillering and growing two rice cultivars under controlled daylength conditions. The findings contribute to resolving inconsistencies in the literature and highlight the importance of photoperiod in designing climate-smart rice management practices.\u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Ethics statement\u003c/h2\u003e \u003cp\u003eThis study was performed in accordance with Institute-approved guidelines and regulations. The test varieties were provided by SeoYeong Yang of the Rice Production and Physiology Division of the National Institute of Crop science (NICS). We obtained permission from the NICS to use these varieties (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.nics.go.kr/apo/breed.do?m=100000128\u0026amp;homepageSecod=nics\u003c/span\u003e\u003cspan address=\"https://www.nics.go.kr/apo/breed.do?m=100000128\u0026amp;homepageSecod=nics\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Experimental materials and design\u003c/h2\u003e \u003cp\u003eA pot experiment was conducted using a completely randomized design incorporating two factors of variation (daylength and tiller removal) at two levels of variation each (short and long day, and with and without tillers removed). Two experiments were conducted in a controlled environment facility (ENT Inc, Boocheon, Korea) at the National Institute of Crop Science in Jeonju, South Korea (35\u0026deg;49ʹ19ʺ N, 127\u0026deg;8ʹ56ʺ E), where light intensity, temperature, and humidity can be artificially controlled (Figure. S1). Lights were turned on at 0730 h regardless of daylength treatment, such that daylength was adjusted by the lights-off time. Two rice cultivars representing ecotypes with different maturation times were used, namely, early maturing \u0026lsquo;Odae\u0026rsquo; (\u003cem\u003eOryza sativa\u003c/em\u003e ssp. \u003cem\u003ejaponica\u003c/em\u003e, IT218242) and mid-late maturing \u0026lsquo;Saenuri\u0026rsquo; (\u003cem\u003eOryza sativa\u003c/em\u003e ssp. \u003cem\u003ejaponica\u003c/em\u003e, IT235281).\u003c/p\u003e \u003cp\u003eFifteen-day-old seedlings of both varieties were transplanted into 1/5000 a Wagner pots at a density of three plants per pot. A composite slow-release fertilizer was applied with 9, 4.5, and 5.7 kg nitrogen, phosphate, and potassium per 1000 m\u003csup\u003e2\u003c/sup\u003e, respectively, at a rate based on the area used by three plants (i.e., 0.042 m\u003csup\u003e2\u003c/sup\u003e; planting distance: 30 \u0026times; 14 cm) instead of the entire pot area. Tillers were removed every 2\u0026ndash;3 d starting 7 d after transplanting, and water was continuously applied at a depth of 2\u0026ndash;3 cm or more. A plant with tillers removed is shown in Figure S2. These procedures were performed as previously described [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Experiment 1: Preliminary test of growth and heading responses to tiller removal under short-day conditions\u003c/h2\u003e \u003cp\u003eTemperature was set to 22\u0026deg;C (maximum 28\u0026deg;C/minimum 18\u0026deg;C) and daylength was fixed to relatively short conditions (12 h 30 min light/11 h 30 min dark) from sowing to the heading stage[\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The light intensity was set at 700 \u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e photosynthetically active radiation (PAR) and the relative humidity was set at 65% [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Experiment 2: Analysis of growth and heading upon tiller removal under short- and long-day conditions\u003c/h2\u003e \u003cp\u003eBefore tiller removal, the temperature was set to 28\u0026deg;C (maximum 33\u0026deg;C/minimum 23\u0026deg;C) for 22 d (15 d after sowing and 7 d after transplanting), and to minimize the induction of photosensitivity, daylength was set to 15 h [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], which is slightly longer than that generally used as a long-day condition (14 h 30 m light/9 h 30 m dark). The long-day condition was set before tiller removal to differentiate the photosensitive response to daylength conditions after tiller removal. Daylength conditions after tiller removal were matched between short (12 h light/12 h dark) and long (14 h 30 m light/9 h 30 m dark) days [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], and the temperature was set to 28\u0026deg;C (maximum 33\u0026deg;C/minimum 23\u0026deg;C).\u003c/p\u003e \u003cp\u003eAfter the heading stage date, conditions were adjusted to 25\u0026deg;C (maximum 30\u0026deg;C/minimum 20\u0026deg;C) and long day (14 h light/10 h dark) during the ripening stage. Temperature and daylength were changed again after the ripening stage, as 28\u0026deg;C is deemed excessively high for the ripening stage, which could present challenges in accurately evaluating grain weight [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. Additionally, different daylength conditions can affect grain weight; therefore, we set the same daylength condition again for the ripening stage. These conditions were set to observe the effect of temperature and daylength up to the heading stage. The light intensity was set at 700 \u0026micro;mol m\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e s\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e PAR and the relative humidity at 65%.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Growth and development measurements\u003c/h2\u003e \u003cp\u003eFor the plant growth analysis, a total of 20 individual plants were analyzed as biological replicates. Plant height was measured from the ground to the top of the apical leaf tip. Stem length was measured from the ground to the uppermost internode. Leaf age is the leaf number formed on the main stem. Leaf age was calculated using the following equation:\u003cdiv id=\"Equa\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equa\" name=\"EquationSource\"\u003e\n$$\\:Leaf\\:age=\\left(n-1\\right)+(m\u0026divide;M)$$\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere, n, M, and m are the total number of leaves, including incomplete leaves, length of the second fully expanded leaf from the top, and length of the unexpanded leaf derived from the second leaf sheath, respectively. Leaf age is used as an indirect indicator to assess the transition among growth stages [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. In both experiments, the heading date was calculated as the number of days (growth period) after transplanting, before panicle emergence from the leaf sheath. Panicle emergence was examined daily from 1300\u0026ndash;1400 hrs. Fifteen plants were used to analyze heading date and growth. These procedures were performed as previously described [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e2.6 RNA extraction and gene expression\u003c/h2\u003e \u003cp\u003eFor RNA expression analysis, three individual plants were used with two leaves collected from each plant. Each leaf sample was further analyzed in triplicated technical replicates. Two plant leaves were sampled, namely the 2nd and 3rd leaves of the main stem and tiller, immediately frozen under liquid nitrogen, and stored at -80\u0026deg;C until RNA extraction. The sampling of the 2nd and 3 \u003csup\u003erd\u003c/sup\u003e leaves has a more relatively stable physiological response because the 1st is a leaf that is still developing. Three biological replicates per treatment, with each replicate comprising three plants. For each plant, the 2nd and 3rd leaves were sampled and utilized for real-time polymerase chain reaction (RT-PCR). Technical replicates were performed thrice per biological replicate to ensure statistical robustness and accuracy. Plant material for RNA extraction was sampled at 1000 hrs. (2.5 h after lights were turned on) because \u003cem\u003eHd3a, RFT1, Ehd1, Ghd7\u003c/em\u003e, and \u003cem\u003eMFT1\u003c/em\u003e reportedly maintain a high expression level for 0\u0026ndash;4 h after plant exposure to light [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. Total RNA was extracted according to the protocol by Chang et al., [\u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. cDNA synthesis was performed using a Primescript RT reagent kit with gDNA eraser (TaKaRa Bio, Inc, Kusatsu, Japan). For RT-PCR, SYBR Green (SYBR Realtime PCR Master Mix, Toyobo, Japan) was used as a fluorescent dye. The analysis was conducted using a Roter-Gene 6000 (Corbett Research, Australia). All experiments were performed in triplicate. Relative expression values were calculated using the reference gene ubiquitin for comparison of Ct values. These values were then normalized to a baseline of 1.0, with the sample collected 1 day prior to the day-length, and tiller removal treatments were used as the reference. Primer sequences are listed in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e. The procedures were performed as previously described [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e2.7 Statistical analysis\u003c/h2\u003e \u003cp\u003eStatistical analysis was performed using R software (version 4.0.3, R Foundation, Austria). Significant differences were assessed at p\u0026thinsp;\u0026lt;\u0026thinsp;0.05 using a one-sample t-test and ANOVA, followed by Duncan's multiple range test. Before statistical analyses, Levene\u0026rsquo;s test and the Shapiro-Wilk test were performed to assess the homogeneity of variance and normality of the data, respectively. When the assumptions of homogeneity or normality were not met, non-parametric tests, such as the Kruskal-Wallis test, were employed as they are more suitable for small sample sizes (n\u0026thinsp;=\u0026thinsp;9 for RNA expression). Parametric tests, such as ANOVA were applied if the assumptions were met. This approach allowed us to rigorously assess the effects of high temperature and ozone on plant growth and physiological responses, including dry weight, plant height, leaf age, stomatal conductance, and stress-related gene expression, both before and after the treatments. Eq.\u0026nbsp;(\u003cspan refid=\"Equ1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e] was used to model the development of plant height, leaf age, and tiller number based on the number of growing days from transplanting:\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\u003cdiv format=\"TEX\" class=\"mathdisplay\" id=\"FileID_Equ1\" name=\"EquationSource\"\u003e\n$$\\:F=\\frac{{H}_{max}\\:or\\:{L}_{max}\\:or\\:{T}_{max}\\:}{1+{e}^{-\\left(t-tm\\right)\\text{*}rF}}$$\u003c/div\u003e\u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\u003c/div\u003e\u003c/p\u003e \u003cp\u003ewhere, \u003cem\u003eH\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e, \u003cem\u003eL\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e, \u003cem\u003eT\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e, \u003csub\u003er\u003c/sub\u003e\u003cem\u003eF, t\u003c/em\u003e, and \u003cem\u003etm\u003c/em\u003e are the final plant height, final leaf age, final number of tillers, rate of development up to final plant height, leaf age, or tiller number, the number of days after transplanting, and timepoint at which half of the final plant height or leaf age or tiller number was achieved, each referring to the timepoint when plant height, leaves, or tillers reached the maximum rate of development, respectively. Successively, \u003cem\u003eH\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e, \u003cem\u003eL\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e, \u003cem\u003eT\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e, \u003csub\u003er\u003c/sub\u003e\u003cem\u003eF\u003c/em\u003e, and \u003cem\u003etm\u003c/em\u003e are coefficients determined by nonlinear regression analysis performed using Sigmaplot v11.1. These procedures were performed as previously described [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Daylength-mediated effects of tiller removal on plant growth and development\u003c/h2\u003e \u003cp\u003eThis study examined main stem growth and development, with and without tillers, under varying daylength conditions. The data showed that under long days, plant height (\u003cem\u003eH\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e) in the tiller-removal treatment (TR) group exhibited a trend of increase in both cultivars compared to the control group. However, under short days, which are known to promote flowering [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], \u003cem\u003eH\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e decreased in the TR group for \u0026lsquo;Saenuri\u0026rsquo; but remained unchanged for \u0026lsquo;Odae\u0026rsquo; (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea, b; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Under short days, \u003cem\u003eH\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e in the TR and control groups was 89.9 cm and 89.8 cm for \u0026lsquo;Odae,\u0026rsquo; and 72.4 cm and 75.3 cm for \u0026lsquo;Saenuri,\u0026rsquo; respectively. Furthermore Under long days, the rate of increase in plant height (\u003csub\u003er\u003c/sub\u003e\u003cem\u003eF\u003c/em\u003e) was lower in the TR group compared to the control. However, the period of increase (\u003cem\u003et\u003c/em\u003e\u003csub\u003em\u003c/sub\u003e) in plant height was longer in the TR group (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea,b; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). However, under short days, \u003csub\u003er\u003c/sub\u003e\u003cem\u003eF\u003c/em\u003e was higher in the TR than in the control group; concomitantly, tm was shorter for \u0026lsquo;Saenuri,\u0026rsquo; whereas in \u0026lsquo;Odae,\u0026rsquo; it differed slightly compared with that observed under long days.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eMeanwhile, Lmax of the main stem was higher in the TR group than that in the control for both varieties across the experimental conditions (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Evidently, under SD conditions, it was slightly lower in the TR in both cultivars; however, it differed between the two cultivars under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). In contrast, tm was longer in the TR groups under all conditions for both cultivars (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Under SD conditions, 'Odae' exhibited a slight increase in Lmax from 13.0 to 13.6 under TR group, with tm extending from 5.6 to 7.0 days. Conversely, under LD conditions, Lmax increased more significantly from 14.2 to 17.1, and tm extended from 9.3 to 14.5 days (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). For 'Saenuri,' Lmax similarly increased from 13.1 to 13.8 in the SD TR treatment, with tm slightly increasing from 6.2 to 6.4 days. Under LD conditions, Lmax increased from 16.9 to 18.6, and tm extended from 14.3 to 16.0 days (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec,d; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). rF declined under LD conditions compared to SD in both cultivars, with 'Odae' showing a reduction from 0.081 to 0.066 and 'Saenuri' from 0.090 to 0.054 in the control treatments. Interestingly, rF remained consistent or slightly increased under the TR treatments, suggesting that tiller removal may have mitigated the impact of LD on leaf development. Additionally, Tmax was lower under short than under long days for both cultivars (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee,f; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eDifferences in growth at the heading stage, i.e., after vegetative growth was completed, in response to tiller removal as per daylength are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Similar to the results described for plant height (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea,b), stem length was greater in the tiller removal than that in the control group under long days, whereas no difference was observed under short days (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea,b). Panicle length was only slightly greater in the tiller removal treatment under short days but showed a substantial increase under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec,d).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eOverall, the TR treatment increased vegetative growth of the main stem under long days; however, under short days, growth was either smaller or did not significantly differ between the TR and control treatments (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e; Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eParameters of the logistic function used to describe plant height, leaf age, and tiller development from sowing to heading stage date after transplanting for the tiller removal treatments according to daylength.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"15\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c14\" colnum=\"14\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c15\" colnum=\"15\"\u003e\u003c/div\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eVarieties\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c3\" namest=\"c2\" rowspan=\"2\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c7\" namest=\"c4\"\u003e \u003cp\u003ePlant height\u003c/p\u003e \u003cp\u003e(cm)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c11\" namest=\"c8\"\u003e \u003cp\u003eLeaf age\u003c/p\u003e \u003cp\u003e(ea)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c15\" namest=\"c12\"\u003e \u003cp\u003eTiller number\u003c/p\u003e \u003cp\u003e(ea)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cem\u003eH\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e \u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003eF\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u0026dagger;\u0026dagger;\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u0026dagger;\u0026dagger;\u0026dagger;\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003eR\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e\u003cem\u003eL\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e \u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e\u003csup\u003e\u003cem\u003er\u003c/em\u003e\u003c/sup\u003e\u003csub\u003e\u003cem\u003eF\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003csup\u003e\u003cem\u003et\u003c/em\u003e\u003c/sup\u003e\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003eR\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e\u003cem\u003eT\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e\u003csup\u003e\u0026dagger;\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e\u003cem\u003er\u003c/em\u003e\u003csub\u003e\u003cem\u003eF\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e\u003cem\u003et\u003c/em\u003e\u003csub\u003e\u003cem\u003em\u003c/em\u003e\u003c/sub\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003eR\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lsquo;Odae\u0026rsquo;\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eSD\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89.8\u003c/p\u003e \u003cp\u003e(1.74)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.078\u003c/p\u003e \u003cp\u003e(0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e7.2\u003c/p\u003e \u003cp\u003e(0.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.0\u003c/p\u003e \u003cp\u003e(0.14)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.081\u003c/p\u003e \u003cp\u003e(0.005)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e5.6\u003c/p\u003e \u003cp\u003e(0.51)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e15.1\u003c/p\u003e \u003cp\u003e(0.49)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.232\u003c/p\u003e \u003cp\u003e(0.051)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e15.7\u003c/p\u003e \u003cp\u003e(1.04)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e0.96\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89.9\u003c/p\u003e \u003cp\u003e(1.71)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.082\u003c/p\u003e \u003cp\u003e(0.007)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.3\u003c/p\u003e \u003cp\u003e(0.86)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.6\u003c/p\u003e \u003cp\u003e(0.19)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.079\u003c/p\u003e \u003cp\u003e(0.005)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e7.0\u003c/p\u003e \u003cp\u003e(0.65)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eLD\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e91.0\u003c/p\u003e \u003cp\u003e(3.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.057\u003c/p\u003e \u003cp\u003e(0.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e9.7\u003c/p\u003e \u003cp\u003e(1.90)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e14.2\u003c/p\u003e \u003cp\u003e(0.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.066\u003c/p\u003e \u003cp\u003e(0.003)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e9.3\u003c/p\u003e \u003cp\u003e(0.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e19.9\u003c/p\u003e \u003cp\u003e(0.47)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.294\u003c/p\u003e \u003cp\u003e(0.056)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e16.2\u003c/p\u003e \u003cp\u003e(0.66)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e108.3\u003c/p\u003e \u003cp\u003e(4.29)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.054\u003c/p\u003e \u003cp\u003e(0.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e15.4\u003c/p\u003e \u003cp\u003e(1.84)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e17.1\u003c/p\u003e \u003cp\u003e(0.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.058\u003c/p\u003e \u003cp\u003e(0.002)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e14.5\u003c/p\u003e \u003cp\u003e(0.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"3\" rowspan=\"4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lsquo;Saenuri\u0026rsquo;\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eSD\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e75.3\u003c/p\u003e \u003cp\u003e(1.27)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.081\u003c/p\u003e \u003cp\u003e(0.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8.1\u003c/p\u003e \u003cp\u003e(1.06)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.1\u003c/p\u003e \u003cp\u003e(0.10)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.090\u003c/p\u003e \u003cp\u003e(0.005)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e6.2\u003c/p\u003e \u003cp\u003e(0.52)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e15.7\u003c/p\u003e \u003cp\u003e(0.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.239\u003c/p\u003e \u003cp\u003e(0.029)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e14.6\u003c/p\u003e \u003cp\u003e(0.56)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.4\u003c/p\u003e \u003cp\u003e(1.03)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.084\u003c/p\u003e \u003cp\u003e(0.008)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6.4\u003c/p\u003e \u003cp\u003e(0.94)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.97\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e13.8\u003c/p\u003e \u003cp\u003e(0.13)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.089\u003c/p\u003e \u003cp\u003e(0.006)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e6.4\u003c/p\u003e \u003cp\u003e(0.63)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eLD\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e86.4\u003c/p\u003e \u003cp\u003e(1.89)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.053\u003c/p\u003e \u003cp\u003e(0.004)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.8\u003c/p\u003e \u003cp\u003e(1.25)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e16.9\u003c/p\u003e \u003cp\u003e(0.23)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.054\u003c/p\u003e \u003cp\u003e(0.003)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e14.3\u003c/p\u003e \u003cp\u003e(0.79)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e19.9\u003c/p\u003e \u003cp\u003e(0.77)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.324\u003c/p\u003e \u003cp\u003e(0.123)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e16.2\u003c/p\u003e \u003cp\u003e(1.21)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e0.91\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e107.0\u003c/p\u003e \u003cp\u003e(4.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.046\u003c/p\u003e \u003cp\u003e(0.005)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e22.6\u003c/p\u003e \u003cp\u003e(2.41)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.98\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e18.6\u003c/p\u003e \u003cp\u003e(0.17)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.058\u003c/p\u003e \u003cp\u003e(0.002)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e16.0\u003c/p\u003e \u003cp\u003e(0.54)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.99\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c14\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c15\"\u003e \u003cp\u003e-\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eSD: short day, LD: long day.\u003c/p\u003e \u003cp\u003eTiller X refers to the TR treatment.\u003c/p\u003e \u003cp\u003e\u0026dagger; Hmax is the final plant height, Lmax is the final leaf age from the main stem, and Tmax is the final number of tillers.\u003c/p\u003e \u003cp\u003e\u0026dagger;\u0026dagger; rF is the rate of development up to the final plant height, leaf age, and tiller number.\u003c/p\u003e \u003cp\u003e\u0026dagger;\u0026dagger;\u0026dagger; t is the number of days after transplantation; tm is the time point at which the plant reached half of its final height, leaf age, and tiller number.\u003c/p\u003e \u003cp\u003e** P\u0026thinsp;\u0026lt;\u0026thinsp;0.01.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Effect of tiller removal on heading response and yield components\u003c/h2\u003e \u003cp\u003eWhen other relevant factors, such as fertilization, are controlled, tiller development is generally enhanced as a result of the longer growth duration [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. Under the short-day conditions used in Experiment 1, days to heading (DTH) was shortened in the TR compared with that in the control treatment group for both cultivars (Figure S3). Further, in Experiment 2, we evaluated DTH under two daylength conditions (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e) and found that under short days, DTH was shortened in the TR compared with that in the control group, similar to that of the results of Experiment 1. Conversely, DTH was longer in the TR than that in the control group under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Under SD conditions, TR reduced the heading date by 3 days in both \u0026lsquo;Odae\u0026rsquo; and \u0026lsquo;Saenuri.\u0026rsquo; In contrast, under LD conditions, TR delayed the heading date by 5 days in \u0026lsquo;Odae\u0026rsquo; and approximately 2 days in \u0026lsquo;Saenuri.\u0026rsquo;. The ANOVA revealed that no significant difference was observed in DTH due to TR, although it showed a highly significant difference as a result of the interaction between daylength and TR (Table S3).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAmong yield components, spikelet number per panicle (SPP) showed the largest change associated with TR and daylength treatments (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Particularly, SPP was lower under short than under long days for both control and TR groups (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Additionally, SPP showed a greater daylength-mediated variation in the TR than that in the control group (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Furthermore, in the \u0026lsquo;Saenuri\u0026rsquo; cultivar, SPP was the lowest (62.2) and highest (235.0) in the TR group under short and long days, respectively, with a 3.78-fold difference between the two extreme values (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). The proportion of ripened grain slightly decreased in the TR treatment, particularly under short days, in which case SPP actually increased significantly (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Further, 1000-grain weight did not significantly differ between the experimental groups for either cultivar (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Similar results were found for Experiment 1 (Table S2).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eChanges in yield components upon tiller removal according to daylength from sowing to heading stage date.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"10\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eVarieties\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c5\" namest=\"c3\"\u003e \u003cp\u003eTreatment\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ePanicle\u003c/p\u003e \u003cp\u003enumber\u003c/p\u003e \u003cp\u003e(ea)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003eSpikelet number per panicle\u003c/p\u003e \u003cp\u003e(ea)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eRipened\u003c/p\u003e \u003cp\u003eGrain\u003c/p\u003e \u003cp\u003e(%)\u0026dagger;\u0026dagger;\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e1000-\u003c/p\u003e \u003cp\u003eGrain weight\u003c/p\u003e \u003cp\u003e(g)\u0026dagger;\u0026dagger;\u0026dagger;\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\" morerows=\"8\" rowspan=\"9\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"3\" nameend=\"c2\" namest=\"c1\" rowspan=\"4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lsquo;Odae\u0026rsquo;\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eSD\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\" morerows=\"7\" rowspan=\"8\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.0a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e56.9c\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e95.6a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.1a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.0b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e74.1b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e84.3b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.1a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eLD\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.5a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e58.2c\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e95.6a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.4a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.0b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e127.1a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e78.5c\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.4a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" morerows=\"3\" nameend=\"c2\" namest=\"c1\" rowspan=\"4\"\u003e \u003cp\u003e\u003cb\u003e\u0026lsquo;Saenuri\u0026rsquo;\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eSD\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e13.8a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e62.2b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e93.8a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.9a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.0b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e59.3b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e72.6c\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e30.3a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c3\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003eLD\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eControl\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e14.0a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e69.1b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e89.7a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.0a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003eTiller X\u003c/b\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e1.0b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e235.0a\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003e79.7b\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003e28.3a\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"9\" nameend=\"c10\" namest=\"c2\"\u003e \u003cp\u003eAnalysis of variance (ANOVA)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eVariety (V)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\" morerows=\"6\" rowspan=\"7\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eDaylength (D)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eTiller (R)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInteraction (V*D)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInteraction (V*R)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInteraction (D*R)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c5\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003eInteraction (V*D*R)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e***\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eSD: short day, LD: long day.\u003c/p\u003e \u003cp\u003eTiller X refers to the TR (tiller removal) treatment.\u003c/p\u003e \u003cp\u003ens: non-significant (P\u0026thinsp;\u0026ge;\u0026thinsp;0.05), *, **, ***: significant at P\u0026thinsp;\u0026lt;\u0026thinsp;0.05, 0.01, and 0.001.\u003c/p\u003e \u003cp\u003eLetters indicate significant differences (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05).\u003c/p\u003e \u003cp\u003e\u0026dagger; Number of days from sowing to heading date (main stem).\u003c/p\u003e \u003cp\u003e\u0026dagger;\u0026dagger; Final leaf age from the main stem; final tiller number was the highest up to the heading date.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Florigen- and spikelet formation-related gene expression\u003c/h2\u003e \u003cp\u003eFlorigen gene \u003cem\u003eHd3a-\u003c/em\u003eexpression levels significantly increased under short than under long days at 3 and 7 d after treatment (DAT, Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea). At 7 DAT under short days, \u003cem\u003eHd3a\u003c/em\u003e levels were 102.4, 79.0, and 75.8 in the main stem of the treatment (TMS), control (CMS), and tillers of the control (CT, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea) groups, respectively. Additionally, the expression of \u003cem\u003eHd3a\u003c/em\u003e in the main stem of the TR group tended to increase under short days and increased over time after TR treatment. However, under long days, \u003cem\u003eHd3a\u003c/em\u003e expression decreased compared with that of its level before daylength treatment, with no discernible difference between TR groups.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe MOTHER OF FT AND TFL1 (MFT1) gene reportedly increases SPP and is associated with delayed flowering [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Similar to that of the heading and SPP responses induced by daylength and TR treatments, MFT1 expression differed considerably between daylength conditions. Particularly, the MFT1 expression level was higher in the CMS and CT than that in the TMS groups under short days (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb); however, the opposite trend was observed under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb).\u003c/p\u003e \u003cp\u003eAt 7 DAT under short-day conditions, the expression of \u003cem\u003eHd3a\u003c/em\u003e relative to \u003cem\u003eMFT1\u003c/em\u003e \u003cb\u003e(\u003c/b\u003e\u003cem\u003eHd3a/MFT1\u003c/em\u003e\u003cb\u003e)\u003c/b\u003e increased under the TR treatments, with values of 13.8, 8.6, and 7.4 for TMS, CMS, and CT, respectively. Contrastingly, at 3 DAT under long-day conditions, the expression of \u003cem\u003eHd3a\u003c/em\u003e relative to \u003cem\u003eMFT1\u003c/em\u003e decreased under the TR treatments, with values of 0.2, 0.5, and 0.5 for TMS, CMS, and CT, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec). These results indicate that the expression levels of the two genes vary depending on daylength conditions\u003c/p\u003e \u003cp\u003eOther flowering-related genes were analyzed together (Figure S4). Therefore, for example, \u003cem\u003eRFT1\u003c/em\u003e, which is another florigen gene controlling flowering under short and long days [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] showed relative expression levels of 61.1, 55.5, and 55.1 in the TMS, CMS, and CT groups, respectively, under short days (Figure S4a). Similarly, the relative expression levels of \u003cem\u003eEhd1\u003c/em\u003e, which enhances the expression of \u003cem\u003eHd3a\u003c/em\u003e and \u003cem\u003eRFT1\u003c/em\u003e under short-day conditions [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e], were 20.1, 19.2, and 14.7 in the TMS, CMS, and CT groups, respectively (Figure S4b). Simultaneously, the relative expression levels of \u003cem\u003eGhd7\u003c/em\u003e under long days, which suppresses the expression of \u003cem\u003eHd3a\u003c/em\u003e and \u003cem\u003eRFT1\u003c/em\u003e under such conditions [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], were 1.9, 1.7, and 1.4 in the TMS, CMS, and CT groups, respectively (Figure S4c).\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eRice is grown over a wide range of latitudes globally; therefore, the plant grows under different daylength conditions depending on the specific location, ranging from approximately 12 h in low-latitude regions to 13\u0026ndash;14.5 h in high-latitude regions [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Even within the same region, it will grow under different daylength conditions depending on climate change or planting season [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eTillering is greatly affected by temperature and daylength [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Generally, short days and high temperature lead to earlier flowering as a result of the restriction of tillering imposed by the shortened vegetative growth period [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e]. However, currently, the interaction between tillering and flowering has not been fully elucidated and in fact remains a controversial issue.\u003c/p\u003e \u003cp\u003eFloral induction is essential for flowering [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], and as it initiates a shift toward reproductive growth, it serves as a key regulator of the vegetative growth period [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e]. Further, because tillering mainly occurs during the vegetative growth period, it is strongly influenced by developmental processes such as floral induction [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. Specifically, FLOWERING LOCUS C (FLC) and FRIGIDA (FRI), two floral repressors in the vernalization pathway, reportedly regulate tillering in \u003cem\u003eArabidopsis thaliana\u003c/em\u003e [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e, \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e] and similar related studies were reported in other species [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e, \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSince the initial discovery of the \u003cem\u003eMOC1\u003c/em\u003e gene as a crucial regulator of rice tillering, several studies were conducted at both physiological and molecular levels [\u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e, \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e48\u003c/span\u003e]. Therefore, for example, the correlation between vegetative growth (e.g., tiller and leaf development depending on nitrogen supply) and flowering time was investigated [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral studies reported a negative relationship between tillering and flowering [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. The FAC is a structure in which \u003cem\u003eHd3a\u003c/em\u003e binds to 14-3-3 proteins acting as intracellular receptors, and \u003cem\u003eOsFD\u003c/em\u003e, a transcription factor in the bzip region, is attached to this complex and promotes floral induction [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. These FACs activate \u003cem\u003eOsMADS 14\u003c/em\u003e and \u003cem\u003e15\u003c/em\u003e, genes located downstream from \u003cem\u003eHd3a\u003c/em\u003e promoting floral formation and development [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. However, other \u003cem\u003eOsFD-\u003c/em\u003elike transcription factors bound to FAC participate in lateral branching in the axillary meristem [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e] and leaf development [\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e]. Therefore, \u003cem\u003eHd3a\u003c/em\u003e promotes lateral branching in the axillary meristem and leaf development over floral induction [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Additionally, \u003cem\u003eOsLUX\u003c/em\u003e-overexpressing mutants show reduced photoperiod sensitivity and a prolonged juvenile phase, which successively results in an increased number of tillers and delayed heading [\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, tillering and flowering were reported to be positively correlated [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. The number of tillers reportedly increases with flowering induced by the overexpression of \u003cem\u003eOsRFL\u003c/em\u003e, which regulates the flowering activator \u003cem\u003eOsSOC1\u003c/em\u003e. Conversely, \u003cem\u003eRFL\u003c/em\u003e knockdown results in the restriction of development of secondary tillers and panicle branches, and delay in flowering [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. Similarly, when the expression of \u003cem\u003eOsWDRa\u003c/em\u003e or \u003cem\u003eOsTRx1\u003c/em\u003e of the COMPASS-like complex was reduced by RNA interference under long and short days, secondary branches and grain number decreased concomitant with delayed heading [\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHere, we found that these contrasting results may be influenced by daylength (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). The data showed that, when tillers were removed, the heading stage was reached earlier under short days, whereas it was delayed under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, S3). Similar results were observed when tiller development was restricted [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. It is likely that, in conjunction with the FAC complex, \u003cem\u003eHd3a\u003c/em\u003e may promote floral induction rather than lateral branching in the axillary meristem under conditions of restricted tiller development [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. Based on this hypothesis, we analyzed the florigen \u003cem\u003eHd3a\u003c/em\u003e in the main stem and tiller under each of these treatment conditions (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea). We observed that under short days the relative expression levels of the florigen genes increased with treatment time. Furthermore, under short days the relative expression levels of both florigens (\u003cem\u003eHd3a\u003c/em\u003e and \u003cem\u003eRFT1\u003c/em\u003e) in the main stem, from which the tillers were removed, increased compared to those in the control (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea, S4a). This change in gene expression may provide a novel insight into the early heading stage transition after tiller removal under short days.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eUnder SD conditions, differences in \u003cem\u003eH\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e responses to TR were observed between \u0026lsquo;Saenuri\u0026rsquo; and \u0026lsquo;Odae.\u0026rsquo; Specifically, \u003cem\u003eH\u003c/em\u003e\u003csub\u003e\u003cem\u003emax\u003c/em\u003e\u003c/sub\u003e decreased in the TR group for \u0026lsquo;Saenuri\u0026rsquo; but remained unchanged for \u0026lsquo;Odae\u0026rsquo; (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea, b). These differences suggest cultivar-specific responses to photoperiod and tiller removal. While these findings highlight distinct responses between the cultivars, we did not conduct detailed analyses of the genetic or physiological mechanisms underlying these differences. Further research is needed to investigate the genetic regulation or physiological traits driving these contrasting responses.\u003c/p\u003e \u003cp\u003eMeanwhile, \u003cem\u003eHd3a\u003c/em\u003e had a less prominent role under long than that under short days, whereas SPP increased markedly in the TR group under long days (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). For cultivar \u0026lsquo;Saenuri\u0026rsquo; under short days, SPP of the TR group (59.3) was less than that of the control group (62.2); however, under long days, SPP for the TR group (235) was 3.4 times greater than that of the control group (69.1) (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Generally, the heading date is delayed in situations of expanding quantitative growth, such as an increase in SPP due to excessive nitrogen supply [\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e]. To interpret these results, we analyzed the expression of the \u003cem\u003eMFT1\u003c/em\u003e gene under each treatment, given its role in the formation of spikelets and branches while suppressing flowering [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. In contrast to short-day conditions, the expression of \u003cem\u003eMFT1\u003c/em\u003e in CMS and CT groups decreased compared to that in the TMS groups under long days (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb). Further, the SPP of TMS groups increased under long days (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Therefore, the phenotype of rice plants, including heading date and SPP, corresponded to the expression of \u003cem\u003eMFT1\u003c/em\u003e.\u003c/p\u003e \u003cp\u003eSummarily, under short-day conditions, in which case floral induction is optimal, \u003cem\u003eHd3a\u003c/em\u003e may play a more prominent role in floral induction of the main stem than that in tillering (i.e., lateral bud formation) in the TR treatment; thus, the time required to reach the heading stage may be shortened (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). Contrastingly, the difference in SPP between TR and control groups under long days was significantly greater than that under short days. Additionally, the characteristics of the expression of the related gene, \u003cem\u003eMFT1\u003c/em\u003e, also showed the same pattern; specifically, \u003cem\u003eMFT1\u003c/em\u003e expression significantly increased in the TR group than that in the control group only under long days. Furthermore, the expression levels of \u003cem\u003eMFT1\u003c/em\u003e showed the opposite pattern to those of \u003cem\u003eHd3a\u003c/em\u003e and \u003cem\u003eRFT1\u003c/em\u003e under short days (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e; FigureS4). Simultaneously, the larger increase in SPP in the TR treatment was the primary factor contributing to the observed delay in flowering under long days, which is in contrast to that of the results obtained under short days.\u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eOur findings highlight the need for climate-smart crop production schemes to address the challenges of optimizing rice growth and productivity under variable daylength conditions. Our study revealed that under LD conditions, reduced tillering increased vegetative growth and delayed days to heading, while under SD conditions, reduced tillering shortened days to heading. These physiological traits could be used to optimise the timing of growth and carbon emissions in rice production. And our study clarified that the variability in tillering and flowering, often associated with conflicting results in previous research, is strongly influenced by daylength. Furthermore, Our findings suggest a novel approach to breeding and management practices by targeting daylength-dependent interactions between rice tillering and flowering, thereby improving adaptability to climate change.\u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eConflict of Interest\u003c/h2\u003e\n\u003cp\u003eThe authors declare no conflicts of interest.\u003c/p\u003e\n\u003ch2\u003eAuthor Contributions\u003c/h2\u003e\n\u003cp\u003eH.S.L. and J.Y.S. conceived and supervised the project. H.S.L. designed the experiments. H.S.L. and J.H.K. conducted the gene expression analysis and field experiments. H.S.L, S.Y.Y, S.H.J, and J.K.B. analyzed the data and drafted the manuscript. All authors discussed the results and contributed to the paper.\u003c/p\u003e\n\u003ch2\u003eFunding\u003c/h2\u003e\n\u003cp\u003eThis work was supported by the Rural Development Administration National Research Project (Project Name: Investigation of metabolic mechanism controlling thermoresponsive flowering time at high temperature), Project No. PJ01486003.\u003c/p\u003e\n\u003ch2\u003eAcknowledgments\u003c/h2\u003e\n\u003cp\u003eWe thank Editage for English language editing.\u003c/p\u003e\n\u003ch2\u003eData Availability Statement\u003c/h2\u003e\n\u003cp\u003eAll data and analyses are included in the main manuscript or Supporting Information. The source data for Figures 1\u0026ndash;5, Tables 1 and 2, Figures S1\u0026ndash;S4, and Tables S1\u0026ndash;S3 are provided as Source Data files.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eBroucek J. Production of methane emissions from ruminant husbandry: A review. 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Plant Cell Rep. 2014;33:363\u0026ndash;71. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00299-013-1536-9\u003c/span\u003e\u003cspan address=\"10.1007/s00299-013-1536-9\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e\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":"bmc-plant-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pbio","sideBox":"Learn more about [BMC Plant Biology](http://bmcplantbiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pbio/default.aspx","title":"BMC Plant Biology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"climate-smart agriculture, rice, tillering, flowering, interaction","lastPublishedDoi":"10.21203/rs.3.rs-5905758/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5905758/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eIntroduction:\u003c/h2\u003e \u003cp\u003eControl of rice tillering and flowering is crucial for reducing greenhouse gas emissions from paddy fields, a key goal of climate-smart agriculture. However, the interaction between tillering and flowering is still debated and poorly understood.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e \u003cp\u003eWe subjected plants of the rice cultivars \u0026lsquo;Saenuri\u0026rsquo; and \u0026lsquo;Odae,\u0026rsquo; to short- and long-day conditions after removing their tillers, and observed growth and flowering responses.\u003c/p\u003e\u003ch2\u003eResults and Discussion\u003c/h2\u003e \u003cp\u003eDifferent daylength conditions yielded contrasting results. Plants in tiller-removal groups grown under short days flowered early compared with that of the controls, whereas the opposite was observed under long days. Further, the expression of the florigen gene, \u003cem\u003eHd3a\u003c/em\u003e, promoting flowering, increased in the tiller-removal group under short days compared with that of the control. Conversely, the expression of the \u003cem\u003eOsMFT1\u003c/em\u003e gene, delaying flowering and increasing the number of spikelets per panicle, was upregulated under long days, and the phenotypic results were consistent. The number of spikelets per panicle in \u0026lsquo;Saenuri\u0026rsquo; and \u0026lsquo;Odae\u0026rsquo; plants in the tiller-removal groups under long day conditions increased approximately 3.4 and 2.2 times, respectively, compared with that of the corresponding control groups.\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e \u003cp\u003eThese findings reveal the daylength-dependent variability in tillering and flowering interactions, offering a novel perspective on their relationship. The results provide a foundation for developing climate-smart rice management practices and breeding strategies to optimize growth timing and enhance productivity under variable photoperiod conditions.\u003c/p\u003e","manuscriptTitle":"Physiological factors influencing climate-smart agriculture: Daylength-mediated interaction between tillering and flowering in rice","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-02-04 08:07:21","doi":"10.21203/rs.3.rs-5905758/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2025-02-05T19:01:09+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-01-31T13:48:03+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-01-31T13:43:14+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Plant Biology","date":"2025-01-26T10:03:48+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-plant-biology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pbio","sideBox":"Learn more about [BMC Plant Biology](http://bmcplantbiol.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pbio/default.aspx","title":"BMC Plant Biology","twitterHandle":"BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"581912a3-f2d4-48fe-8f5b-50642bfeeef9","owner":[],"postedDate":"February 4th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-04-07T16:04:08+00:00","versionOfRecord":{"articleIdentity":"rs-5905758","link":"https://doi.org/10.1186/s12870-025-06430-z","journal":{"identity":"bmc-plant-biology","isVorOnly":false,"title":"BMC Plant Biology"},"publishedOn":"2025-03-31 15:57:31","publishedOnDateReadable":"March 31st, 2025"},"versionCreatedAt":"2025-02-04 08:07:21","video":"","vorDoi":"10.1186/s12870-025-06430-z","vorDoiUrl":"https://doi.org/10.1186/s12870-025-06430-z","workflowStages":[]},"version":"v1","identity":"rs-5905758","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5905758","identity":"rs-5905758","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}