Agronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress

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Moench] varieties to scheduled water stress Fadeyi Olasupo James This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-5664895/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract The 13th sustainable development goal emphasises urgent action to combat climate change and its impacts; in this context, continuous evaluation of drought tolerance traits in crops with high climate-smart potential is imperative. The agronomic responses of three improved sorghum varieties (SAMSORG 44, SAMSORG 47, SAMSORG 48) under severe water stress conditions were investigated in a screen house study in 2022 (August–December) as a 3 × 3 factorial experiment in plastic pots arranged in a completely randomized design (CRD) with three replications. Three soil moisture stress levels [well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions] corresponding to 100, 50 and 25%, respectively, of fractional soil available water (FSAW) determined gravimetrically were imposed at 21 days after sowing (vegetative) and at 50% flowering (reproductive) for 2 weeks. Agronomic (phenological, growth, yield and yield components) parameters measured were not significantly (p < 0.05) influenced by drought stress. There were significant (p < 0.05) interactions between water stress and variety. The three sorghum varieties responded differently (p < 0.05) in terms of FSAW dynamics at both the vegetative and reproductive stages. SAMSORG 44 had a comparatively superior performance, as indicated by its relatively high moisture stress tolerance. These varieties are suggested to be suitable for cultivation under severe drought conditions. Agronomy climate change climate–smart agriculture drought stress drought tolerance Sorghum bicolor sorghum varieties Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Introduction Climate change has recently posed a significant threat to sustainable agriculture worldwide. Its impacts, is characterized by certain phenomena which include increased desertification; prolonged dry season, shifts in the rainfall patterns; delayed onset and early cessation of rainfall; reductions in the length of the growing season; floods; storms; late establishment of steady rainfall; sudden drought experience; reduced production; and changes in the frequency and intensity of extreme weather conditions, such as drought, significantly influence crop yields [1, 2]. Among these challenges, drought is distinctly a crucial abiotic factor that negatively affects crop plant growth and development worldwide and is perhaps the most important abiotic stress limiting agricultural productivity [3, 4]. Projections have suggested that climate shifts effects will becoming increasingly erratic and exacerbate water deficits, leading to expansion of drought-affected arable land, and by 2050, water shortages are expected to impact 67% of the global population [5, 6]. This problem has profound effects on the world’s agriculture and food security, especially in rain-fed dependent agricultural systems [7]. The effects of drought include the impaired growth, disrupted water relations, reduced water use efficiency, and ultimately resulting in decreased crop yield [8]. However, crop varieties exhibit varying levels of resilience to drought stress via several factors [9, 10]. In order to address these challenges, climate-smart agriculture (CSA) mitigation strategies have been identified as viable solutions, one such approach involves the cultivation of resilient crops such as sorghum [11]. The role of sorghum in CSA includes drought tolerance, resistance to pests and diseases, adaptation capability to harsh arid and semiarid regions which is characterized by its extensive roots, waxy leaf coating that minimises water loss, the ability to suspend growth during dry spells as well as resume when conditions improve, the possession of diverse genetic resources, and higher nutritional value attributes [12, 13]. Hence, sorghum holds significant potential and needs to be better explored to mitigating the impacts of climate change. Sorghum [ Sorghum bicolor (L.) Moench], a member of the Poaceae family is the fifth most important cereal crop globally after barley, maize, rice and wheat. In Africa, in terms of yield, it ranks as the third most important cereal crop contributing 26.3 million metric tonnes annually, following maize with 96.6 million metric tonnes and rice having 37.2 million metric tonnes [14]. As a highly valued cereal native to Sub-Saharan Africa, it has been grown for centuries as a major staple food of millions of people in different parts of the tropical and subtropical regions of the world [15]. Similarly, beyond its role as food, sorghum serves as animal feed and industrially, as raw material for the production of alcohol, fiber, fuel, starch, wax, syrup, agar, gluten feed, edible oils, biodegradable packaging materials, solvents, wallboard, fences, and also, in the brewing industry [16, 17]. Researchers have shown that nutritionally sorghum grain is rich in iron, zinc, vitamin B6, vitamin B3 (niacin), magnesium, phosphorus, fibre, unsaturated fats, and protein; gluten free, which makes it a valuable alternative for individuals with wheat allergies ; and some varieties contain high levels of antioxidants, [18]. Studies have revealed that despite sorghum resilience to drought stress, specific stages in its lifecycle such as the early vegetative stage and reproductive stages (pre- and post-flowering) are particularly susceptible to drought stress; therefore, the tolerance ability at these stages is critical to productivity; hence, severe drought stress could lead to crop loss and/or decreased productivity in sorghum [19]. Consequently, the aim of this study was to identify improved drought-tolerant sorghum varieties and subsequently evaluate their agronomic responses to scheduled, severe water stress. The first objective was to investigate the agronomic responses of three improved sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under severe water stress conditions during scheduled water stress at the identified particularly critical stages when sorghum could be susceptible to drought stress. The second objective was to evaluate the distinct varietal agronomic responses of those varieties during scheduled water deficit (moderate and severe stress) at the identified sorghum drought-sensitive growth stages. In this study, we exposed three sorghum varieties with different phenologies and genetic backgrounds to controlled, scheduled drought conditions to investigate the underlying variations in agronomic responses to severe drought. Material and Methods Three sorghum varieties (SAMSORG-44, SAMSORG-47 and SAMSORG-48) were evaluated in this study; these varieties were developed at the Institute of Agricultural Research (IAR), Samaru, Nigeria, and were thus sourced from those locations. SAMSORG 44 is an improved early-maturing cultivar (maturity period = 85–95 days; seed color: white; potential yield: 2.8 tons ha − 1 ) developed for the northern Guinea savanna. SAMSORG-47 is an improved late-maturing cultivar (maturity period = 120–125 days; seed colour: yellow; potential yield: 4.8 tons). ha − 1 ), developed for southern Guinea savanna. SAMSORG-48 is also an improved late-maturing cultivar (maturity period = 120–130 days; seed colour: yellow; potential yield: 4.7 tons). ha − 1 ), which was developed for southern Guinea savanna [20]. The trial was conducted in a screen house located at the Federal University of Agriculture Abeokuta, Nigeria (07 ° 15'N, 03 ° 25'E), in 2022 (August - December). The experiment was conducted in plastic pots arranged in a completely randomized design (CRD) with three replications. The study was designed as a 3 × 3 factorial experiment with three varieties of sorghum subjected to three soil moisture stress levels at two different stages during the crop cycle. The soil moisture stress levels [well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions] were imposed on all three varieties at 21 days after sowing (vegetative) and at 50% flowering (reproductive) for 2 weeks. The moisture stress was imposed once at a particular stage on all stressed plants except the WW plants. The plants were grown in plastic pots perforated at the base and filled with 30 kg of topsoil, watered to field capacity and allowed to drain. Four seeds of each variety were planted in a pot and subsequently thinned to two seedlings per pot at two weeks after emergence. Poultry manure was applied at planting. Weed control was achieved by hand pulling at weekly intervals. The three soil moisture stress levels were created by moistening the pots with different quantities of water corresponding to 100, 50 and 25% of the soil available water (SAW) determined gravimetrically [21]. Before planting, the soil was maintained at 100% field capacity (FC) via the gravimetric method. The soil moisture stress levels were maintained throughout the experimental period by the periodic application of water as needed. The time to 50% flowering and 100% flowering was recorded, which implies that more than 50% of the plants per variety had at least one open panicle and/or when all panicles had opened. The time to physiological maturity was also recorded. (Plant height was measured via a meter rule; the number of leaves was counted and recorded; stem girth was determined via a digital veneer calliper; and dry matter accumulation in the sampled plants oven-dried to constant weight was measured) at 2-week intervals beginning at 4 WAP. The yield and yield components were determined after the plants were harvested and oven-dried to a constant weight. The height at harvest was determined by measuring from the soil level to the tip of the panicle via a meter rule. Panicle length, panicle diameter and panicle weight were measured and recorded, the threshing percentage was calculated as the threshed seed weight divided by the unthreshed panicle weight and expressed as a percentage, the above-ground dry weight (stover weight) and the seed weight were measured and recorded, and the harvest index was computed as the ratio of the seed weight to the above-ground dry weight. The experiment involved a two-factorial (variety and water stress) CRD with three replicates. Agronomic data were analysed via general analysis of variance (ANOVA) in IBM SPSS version 26. Significant (P < 0.05, F test) treatment means of main effects and interactions were separated via Duncan’s multiple range test (DMRT) [22]. Results and Discussion Effects of water stress and variety on the phenology of sorghum The effects of water stress and variety on the days to 50% flowering, days to 100% flowering and days to maturity of sorghum are shown in Table I. The phenological development of sorghum was not significantly (P < 0.05) influenced by drought. The varieties equally differed not significantly (P < 0.05) in their phenological development except in days to maturity (P < 0.01). The maturity days of the varieties increased in the order of SAMSORG 44, SAMSORG 47 and SAMSORG 48 (Table I). A significant water stress × variety interaction occurred for days to maturity as well. SAMSORG 44 matured earlier than the other varieties did at all levels of water stress and was not affected by drought stress as much as the other sorghum varieties were (Figure I). Table I: Phenology of three sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions. Treatments Days to 50% flowering Days to 100% flowering Days to maturity Water stress (T) well-watered 70 78 119 moderately water-stressed 70 78 119 severely water-stressed 70 78 120 SE± 0.1 0.2 3.0 F test ns ns ns Variety (V) SAMSORG 44 70 78 98 a SAMSORG 47 70 78 128 b SAMSORG 48 70 78 132 c SE± 0.1 0.2 3.0 F test ns ns ** Interaction TXV ns ns ** In a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan’s multiple range test (DMRT). WAP = Weeks after planting. ns = not significant. ** = Significant at the 1% level of probability. Among the varieties, SAMSORG 48 maintained the most conservative water use under drought stress, survived the longest and recovered earliest. Similarly, the varieties matured differently in response to the FSAW dynamics. SAMSORG 44 matured earlier than the other methods did. The earlier maturity could be attributed to the capacity of the variety for early maturity [20], which was, however, not influenced by the imposed drought stress. These sorghum varieties likewise varied in response to FSAW dynamics after drought treatment at the reproductive stage. SAMSORG 44 had the most conservative water use. Our study is consistent with earlier studies [9, 10] that have similarly demonstrated differences in the water-use rate during drought stress in sorghum, reporting that sorghum genotypes adapt different mechanisms in response to drought. Effects of water stress and sorghum variety on sorghum growth The effects of water stress and variety on the plant height, number of leaves, stem girth and dry matter accumulation of sorghum are shown in Table II. Drought stress did not significantly (P < 0.05) affect sorghum plant height except at 4 weeks after planting (WAP), when the plant height significantly (P < 0.05) varied. Taller plants (66.8 cm) were recorded in the moderate drought-stress (MWS) treatment (Table II). Sorghum plant height was significantly (P < 0.05) affected by variety. SAMSORG 48 recorded taller plants (130.1 cm) than the other varieties did, which were comparable at 6 WAP, whereas SAMSORG 44 had the tallest plants (161.1 cm) at 8 WAP (Table II). A significant water stress × variety interaction occurred for plant height (P < 0.01). At 4 WAP, only the SAMSORG 48 cultivar in the SWS treatment group presented taller plants and was not affected by drought stress as much as the other sorghum varieties were affected. Conversely, SAMSORG 48 had the tallest plant at 6 and 8 WAP at all levels of water stress, whereas the other varieties were not affected by drought stress (Figure II). Water stress (P < 0.05) and variety (P < 0.05) did not significantly affect the number of leaves of sorghum plants (Table II). The interaction effect of water stress × variety on the number of leaves at 8 WAP was significant. A greater number of leaves were recorded in the SWS treatment for SAMSORG47 and SAMSORG48, and all the varieties were not affected by drought stress. The stem girth of sorghum was significantly (P < 0.05) influenced by water stress (Table II). Drought stress reduced the stem girth of sorghum plants at 4 WAP, and the thickest stem girth was measured in the WW treatment (Table II). However, at 6 and 8 WAP, the highest stem girths were recorded in the MWS treatment, and the girths of sorghum plants in the SWS and WW treatments were comparable. Variety significantly (P < 0.05) affected sorghum stem girth at 6 WAP (Table II). SAMSORG 48 resulted in greater stem girth, whereas the stem girths of SAMSORG 44 and SAMSORG 47 were comparable. A significant water stress × variety interaction occurred for stem girth (P < 0.05). Greater numbers of stem girths were recorded for SAMSORG 48, except at 4 WAP, when SAMSORG 44 presented the thickest stem girth. The varieties were not responsive to drought stress except at 4 WAP, in which stem girth decreased by 13–21% in response to drought stress. Table II: Growth of three sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions. Treatments Plant height (cm) Number of leaves Stem girth (cm) Dry matter accumulation (g) WAP Water stress (T) 4 6 8 4 6 8 4 6 8 4 6 8 well-watered 62.6 b 114.0 154.0 6 8 10 11.8 a 14.3 b 17.3 b 8.7 12.9 17.0 moderately water-stressed 66.8 a 114.1 157.8 6 8 11 10.7 b 14.6 ab 21.9 a 7.2 11.1 14.0 severely water-stressed 60.8 b 116.8 156.8 5 8 10 9.6 c 13.4 c 17.1 b 8.6 12.7 16.1 SE± 0.7 2.1 2.2 0.3 0.1 0.2 0.2 0.2 0.7 0.4 0.7 0.8 F test ** ns ns ns ns ns ** ** ** ns ns ns Variety (V) SAMSORG 44 62 107.8 b 161.1 a 5 8 10 10.6 13.6 b 18.2 7.9 b 11.9 b 15.4 b SAMSORG 47 63.1 107.0 b 151.3 c 5 8 11 10.6 13.8 b 18.3 6.1 c 8.7 c 10.8 c SAMSORG 48 65.1 130.1 a 156.1 b 6 8 11 10.8 14.9 a 19.5 10.6 a 16.1 a 20.7 a SE± 0.7 2.2 1.1 0.3 0.1 0.2 0.2 0.2 0.7 0.4 0.6 0.9 F test ns ** ** ns ns ns ns ** ns ** ** ** Interaction T×V ** ** ** ns ns ** ** ** ** ** ** ** In a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan’s multiple range test (DMRT). WAP = Weeks after planting. ns = not significant. ** = Significant at the 1% level of probability Drought stress did not significantly (P < 0.05) affect sorghum dry matter accumulation (Table II). Conversely, the dry matter accumulation of the sorghum varieties significantly differed. SAMSORG 48 accumulated the driest matter at 4, 6 and 8 WAP (Table II). The interaction effect of water stress and variety significantly affected dry matter accumulation at 8 WAP. Like those of the other sorghum varieties, the dry matter accumulation of SAMSORG 48 plants was greatest at all levels of water stress, and the dry matter accumulation of SAMSORG 48 plants was not affected by drought stress (Figure III). In general, none of the agronomic parameters measured were negatively influenced by drought stress. This is an indication that varieties with the same response potential to severe drought stress conditions. Nonetheless, visible variations were observed in most parameters due to varietal effects, which could be attributed to the genetic capacity of the varieties to exhibit superiority in any specified parameter. The shorter days to maturity of the SAMSORG 44 variety indicates that the variety matured earlier than the other varieties did. The taller plants, thicker stem girth and greater dry matter accumulation of SAMSORG 48 during the growth stage indicate that it has better genetic traits for greater growth. In addition, sometimes higher growth could result in higher yields. The superiority of the seed yield, greater panicle weight, longer panicle length, greater panicle diameter and greater harvest index of the SAMSORG 44 variety over the other varieties is an indication of the greater efficiency of the variety in utilizing the assimilate trans located for panicle development to produce grains. Effects of water stress and variety on the yield and yield components of sorghum Table III presents the effects of water stress and variety on the above-ground dry weight, seed yield, harvest index, panicle length, panicle diameter, panicle weight, and threshing percentage of sorghum. Drought stress did not significantly (P < 0.05) affect sorghum aboveground dry weight. The sorghum above ground dry weight was significantly (P < 0.05) affected by variety. Compared with the other varieties, SAMSORG 47 resulted in higher weights, which were comparable. A significant genotype × water stress interaction occurred for aboveground dry weight (P < 0.05). The aboveground dry weight of the three varieties ranged from 40.3 to 44.8 g plant –1 in the WW treatment but did not decrease in the water-stressed plants (45.8–50.8 g plant –1 ). The aboveground dry weight was highest in SAMSORG 47, followed by SAMSORG 48, and lowest in SAMSORG 44. The seed yield of sorghum was not significantly (P < 0.05) influenced by water stress (Table III). Variety significantly (P < 0.05) affected sorghum seed yield (Table III). SAMSORG 44 presented the highest seed yield. Table 3 Yield and yield components at the final harvest for three sorghum varieties (SAMSORG 44, SAMSORG 47, SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions. Treatments Above ground dry weight (g plant –1 ) Seed yield (g plant –1 ) Harvest index Panicle length (cm) Panicle diameter (cm) Panicle weight (g plant –1 ) Threshing percentage (%) Water stress (T) well-watered 42.9 42.3 98.9 17.4 4.3 48.0 88.2 a moderately water-stressed 45.1 42.5 95.9 18.4 4.8 48.3 88.0 a severely water-stressed 47.0 41.6 89.0 18.0 4.7 48.3 86.1 b SE± 0.8 0.6 2.3 0.7 0.3 0.6 0.4 F test ns ns ns ns ns ns ** Variety (V) SAMSOARG 44 43.3 b 45.0 a 105 a 22.0 a 6.3 a 51.3 a 87.6 SAMSOARG 47 48.4 a 42.9 b 89.2 b 18.1 b 3.2 c 49.5 b 86.7 SAMSOARG 48 43.1 b 38.4 c 89.6 b 13.7 c 4.3 b 43.7 c 88.1 SE± 0.8 0.5 2.3 0.6 0.2 0.6 0.3 F test ** ** ** ** ** ** ns Interaction TXV ** ** ** ** ** ** ** In a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan’s multiple range test (DMRT). WAP = Weeks after planting. ns = not significant. ** = Significant at the 1% level of probability. A significant water stress × variety interaction occurred for seed yield. The seed yield ranged from 34.8 to 44.5 g plant –1 in the WW treatment and from 37.8–46.5 g plant –1 in the drought stress treatment (P < 0.05; Figure IV). Compared with the WW plants, the drought-susceptible plants did not exhibit a decrease in yield, and SAMSORG 44 presented the highest seed yield. Drought stress did not significantly (P < 0.05) affect the harvest index (Table III). Conversely, the Sorghum varieties presented significantly (P < 0.05) different harvest indices. SAMSORG 44 recorded a higher harvest index than the other varieties that were comparable. The interaction effect of water stress and variety significantly affected the harvest index. SAMSORG 44 presented the highest harvest index at all levels of water stress and was not affected by drought stress as much as the other sorghum varieties were (Figure V). The panicle length of sorghum was not significantly (P < 0.05) influenced by water stress (Table III). Variety significantly (P < 0.05) affected sorghum panicle length (Table III). Among the three varieties, SAMSORG 44 presented the longest panicle. A significant water stress × variety interaction occurred for panicle length (P < 0.05). The longest panicles were recorded for SAMSORG 44, and the varieties were not responsive to drought stress. Drought stress did not significantly (P < 0.05) affect panicle diameter (Table III). Conversely, the Sorghum varieties presented significantly (P < 0.05) different panicle diameters. SAMSORG 44 had the thickest panicle diameter (Table 3 ). The interaction effect of water stress and variety significantly affected panicle diameter. SAMSORG 44 had plants with the thickest panicle diameter at all levels of water stress and were not as affected by drought stress as the other sorghum varieties were. The panicle weight of sorghum was not significantly (P < 0.05) influenced by drought. The varieties differed significantly (P < 0.05) in their panicle weights. The panicle weights of the varieties were in increasing order: SAMSORG 44, SAMSORG 47 and SAMSORG 48 (Table III). A significant water stress × variety interaction occurred for panicle weight as well. The SAMSORG 44 and SAMSORG 47 panicle weights were greater than those at all levels of water stress, and all varieties were not affected by drought stress. Drought stress significantly (P < 0.05) affected the sorghum threshing percentage. A lower percentage was recorded in the SWS treatment (Table III). The sorghum threshing percentage was not significantly (P < 0.05) affected by variety. The interaction effect of water stress × variety had a significant effect on the percentage of threshing. Higher threshing percentages were recorded in the MWS treatment for SAMSORG 44 and SAMSORG 47, and all the varieties were not affected by drought stress. The results of this study revealed that drought stress had no significant effect on the phenology, growth, yield or yield components of sorghum. This disproves the earlier report that particular stages of the sorghum lifecycle, such as the early vegetative stage and reproductive stages (pre- and post-flowering), are susceptible to drought stress; hence, severe drought stress could lead to crop yield reduction and decreased productivity [19]. On the basis of the results of the present study, the adaptive ability of these sorghum varieties for severe drought tolerance, even at those identified critical stages, was revealed, indicating that there was a negligible effect of water deficit during the vegetative stage and reproductive stages since the measured parameters of phenology, growth, and yield and yield components of the MWS and SWS plants are comparable to those of the WW crops. Moreover, various researchers have identified four general basic strategies employed as drought resistance mechanisms by drought-tolerant crop plants to mitigate drought stress effects during moisture stress conditions: drought escape, drought avoidance, drought tolerance and drought recovery, although more than one mechanism may be used simultaneously to resist drought [6, 7]. Drought avoidance, drought tolerance and drought recovery might be the mechanisms identified in the present study that were employed simultaneously by the sorghum varieties under investigation. Drought avoidance involves the conservation of water by the plant via a reduction in water loss from the shoots or, alternatively, efficient extraction of water from the soil, which permits a longer growth period in the crop, which results in reduced water use or increased water uptake [23]. Drought tolerance involves the maintenance of a certain level of physiological activities under severe drought stress conditions via gene regulation protocols as well as metabolic pathways to reduce or probably repair the resulting effects of stress, which implies water deficit resistance while maintaining appropriate physiological activities to stabilize and protect cellular and metabolic integrity at the tissue and cellular levels via the accumulation of sugars, polyols, amino acids, alkaloids, etc., to increase their concentration, reduce osmotic potential, and enhance the retention of cell water in response to water stress [24], whereas drought recovery implies the resumption of growth and seed yield after severe moisture stress occurrence, which could cause a complete loss of turgor pressure with leaf dehydration [25]. Conclusion This study revealed that all agronomic (phenological, growth, yield and yield components) parameters measured were not significantly influenced by severe drought stress. The three sorghum varieties responded differently in terms of FSAW dynamics at both the vegetative and reproductive stages. SAMSORG 48 presented greater growth, whereas SAMSORG 44 presented greater seed yield and yield components at all levels of water stress, and all the varieties were not affected by drought stress at either stage. These varieties are highly suitable for severe drought tolerance. SAMSORG 44 had a comparatively superior performance, as indicated by its relatively high moisture Declarations Ethical approval and consent to participate All methods used in this research complied with the relevant institutional, national, and international guidelines and legislation. In addition, since this study does not involve wild plant materials, hence, any formal identification of plant material was not required. Consent for publication Not applicable Availability of data and materials The raw data have been deposited and/or published in the repository with the dataset identifier Fadeyi, Olasupo James (2024), “Agronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress”, Mendeley Data, V1, doi: 10.17632/zwgn543vjw.1 Competing interests The authors have no relevant financial or non-financial interests to disclose. Funding No funding was obtained for this study. Authors’ Contributions Fadeyi, Olasupo James collected, analysed and interpreted the data for the research work and was the major contributor in writing this manuscript. Fabunmi, Thomas Oladeji was a major participant in the interpretation of the data and contributed in writing this manuscript. Olowe, Victor Idowu Olugbenga engaged in data collection monitoring, data interpretation and contributed in writing this manuscript. All authors read and approved the manuscript. Christopher Olu Adejuyigbe is the soil scientist who guided in the soil methodology and interpreted the data collected, he proof read and approved the manuscript. Acknowledgements The authors appreciate the kind gesture of Mr. P.A. S. Soremi, a Lecturer in the Department of Plant Physiology and Crop Production, FUNAAB, for his support in making the facilities at his disposal available, which were necessary for the success of the project. We also thank laboratory scientists of the same department for providing facility and technical support during the recording of various agronomic measurements. References Menezes, C.B., Saldanha, D.C.., Santos, C.V, Andrade, L.C., Júlio M.P., Portugal, A.F., Tardin, F.D. (2015). Evaluation of grain yield in sorghum hybrids under water stress. Genetics and Molecular Research. 14: 12675-12683. Chadalavada, K.B., Kumari, D.R., Kumar, S. (2021). Sorghum mitigates climate variability and change on crop yield and quality. Planta. 253: 1-19. Farooq, M., Hussain, M., Wahid, A., Siddique, K.H.M. (2012). Drought stress in plants: An overview. In: R. Aroca, ed. Plant responses to drought stress: From morphological to molecular features, 1–37. Fathi, A. and Tari, D.B. (2016). Effect of drought stress and its mechanism in plants. International Journal of Life Sciences, 10(1): 1-6. Gupta, A., Rico-Medina, A., Caño-Delgado, A.I. (2020). The physiology of plant responses to drought. Sci. 368: 266–269. Begna, T. (2020). Effects of Drought Stress on Crop Production and Productivity. Intl. J. of Research Studies in Agricultural Sciences. 6: 34-43. Verma, R., Kumar, R., Anamika N. (2018). Drought Resistance Mechanism and Adaptation to Water Stress in Sorghum [Sorghum bicolor (L.) Moench]. Int. J. Biores. &Stress Mgt. 9(1): 167-172. Farooq, M., A. Wahid, N. Kobayashi, D. Fujita and S.M.A. Basra. (2009). Plant drought stress: effects, mechanisms and management. Agron. Sustain. Dev., 29: 185-212. Gholipoor, M., Sinclair, T.R., Prasad, P.V.V. (2012). Genotypic variation within sorghum for transpiration response to drying soil. Plant Soil 357: 35–40. Markos, S., Tamirat, S., Tamirat, S. (2020). Evaluation of improved lowland sorghum ( Sorghum bicolor (L.) Moench) varieties in southern Ethiopia. Cogent Food & Agriculture , 6: 1727624. http://doi.org/101080/23311932.2020.1727624 FAO, (2013). Climate Smart Agriculture: A Resource book. 2013 Hadebe, S.T., Modi, A.T., Mabhaudhi, T. (2017). Drought Tolerance and Water Use of Cereal Crops: A Focus on Sorghum as a Food Security Crop in Sub-Saharan Africa. J. Agr. Crop Sci. 203: 177-191. Samuel, O., Okeyo, S.N., Ndirangu, H., Isaboke, N., Lucy, K.N. (2020). Determinants of sorghum productivity among small-scale farmers in Siaya County, Kenya. African Journal of Agricultural Research. 16(5): 722-731. Yahaya, M.A., Shimelis, H., Nebié, B., Mashilo, J., Pop, G. (2023). Response of African Sorghum Genotypes for Drought Tolerance under Variable Environments. Agronomy. 13: 557 Amal, G., M. S., Hassanein, and Nabila, M. Z. (2018). Grain sorghum as influenced by organic and microcat mix fertilizer. Middle East Journal of Agriculture Research . 7(3): 1041-1048. Agrama, H.A., Tuinstra, M.R. (2003). Phylogenetic diversity and relationships among sorghum accessions using SSRs and RAPDs. Afric. J. Biotech. 2(10): 334-340. Mamoudou H. D, Hurry G, Alfred S, Alphons G.J and Van B. (2006). Sorghum grain as human food in Africa: relevance of content of starch and amylase activities. Afric. J. Biotech 5(5): 384-395. Muui, C.W, Muasya R.M., Kirubi, D.T. (2013). Baseline Survey on factors affecting sorghum production and use in Eastern Kenya. African Journal of Food, Agriculture, Nutrition and Development 13(1): 7339-7357. Devnarain, N., Crampton, B.G., Chikwamba, R., Becker, J.V.W., O'Kennedy, M.M. (2016). Physiological responses of selected African sorghum landraces to progressive water stress and rewatering. South Afr. J. Bot. 103: 61–69. CGIAR. (2018).3 sorghum varieties released in Nigeria . https://www.cgiar.org/news-events/news/3-sorghum-varieties-released-in-nigeria. Accessed 16 December 2024. Duncan, D.B. (1955). Multiple Range and Multiple F Test. Biometrics. 11: 1-5. Kramer, P.J. (1983). Water Relations of Plants. New York Academic Press, New York. Hu, H., Xiong, L. (2014). Genetic engineering and breeding of drought-resistant crops. Annual Review on Plant Biology 65: 715–741. Xiong, L., Wang, R., Mao, G., Koezan, J. (2006). Identification of drought tolerance determinants by genetic analysis of root responses to drought stress and abscisic acid. Plant Physiology 142, 1065–1074. Luo, L.J. (2010). Breeding for water-saving and droughtresistance rice (WDR) in China. Journal of Experimental Botany 61: 3509–3517. Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-5664895","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":391945636,"identity":"d3168f26-42e0-43da-9917-ebc87888ad73","order_by":0,"name":"Fadeyi Olasupo James","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA/0lEQVRIiWNgGAWjYBAC9gYGAwYgYuZnPgDig4gE/Fp4DkC1SLYlkKQFCAyOEa2F/fDGxzwFNuzGx3jMHvyoucPAz55jwFzwC48WnrRiYx6DNGazYzzmhj3HnjFI9rwxYJ7Zh1uLPUOOmTSPwWFms/s9ZhI8bIcZDG4AbeHtwWML/xvz3yAtxm08ZpJ//h1msCeoRSLHjBmkxYCNx0yatw1oiwRQC88PfFqeFUvOAfpF4hhbmbRs3zMeiTPPCg7zNuBzWPLGD2/+2CTztzFvk3zz7Y4cf3syMAz/4NYCAkw8DAzJcDNAxAHGNvxaGIEOt0MTI2DLKBgFo2AUjCgAADMWS4R9xlnpAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0003-4604-0510","institution":"Federal University of Agricuture, Abeokuta","correspondingAuthor":true,"prefix":"","firstName":"Fadeyi","middleName":"Olasupo","lastName":"James","suffix":""}],"badges":[],"createdAt":"2024-12-17 23:34:11","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":true,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":true},"doi":"10.21203/rs.3.rs-5664895/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5664895/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":71838363,"identity":"75295eee-c8ff-4164-8aef-56184d8b7138","added_by":"auto","created_at":"2024-12-19 04:44:42","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":20146,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInteraction of Water Stress and Variety on Days to Maturity of Sorghum\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/9de216e1000a691c2036b8b8.png"},{"id":71838364,"identity":"9f3310dd-b0cd-43be-a6d8-bf18b8a52ff5","added_by":"auto","created_at":"2024-12-19 04:44:42","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":33383,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInteraction of Water stress and Variety on Plant height of Sorghum at 8 WAP\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/f66bd28746db1df2466c5c13.png"},{"id":71838612,"identity":"ed803418-1fdb-498d-a621-984412265c21","added_by":"auto","created_at":"2024-12-19 04:52:43","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":25028,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInteraction of Water Stress and Variety on Dry matter accumulation of Sorghum at 8 WAP\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/d223fc4481ab3ebfd6bee95a.png"},{"id":71838609,"identity":"4ca9c6d3-e04c-4dd3-9c3a-cfa133942e7a","added_by":"auto","created_at":"2024-12-19 04:52:42","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":20327,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInteraction of Water Stress and Variety on Seed yield of Sorghum\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/d0c86a2b3b0c391cab6298f6.png"},{"id":71838381,"identity":"cbcaf7a6-a6e4-4f14-a51f-cbbaea25c102","added_by":"auto","created_at":"2024-12-19 04:44:43","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":21896,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInteraction of Water Stress and Variety on Harvest index of Sorghum\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"5.png","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/6fcc4abbc9a2709cfce67909.png"},{"id":71839396,"identity":"6e4ddc6b-1b63-46bc-9a10-ba35eab83cf8","added_by":"auto","created_at":"2024-12-19 05:00:43","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":880656,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5664895/v1/f295ad2e-9e04-4c39-ae69-80121fcdfdb1.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eAgronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress\u003cbr\u003e\n\u003c/p\u003e","fulltext":[{"header":"Introduction","content":"\u003cp\u003eClimate change has recently posed a significant threat to sustainable agriculture worldwide. Its impacts, is characterized by certain phenomena which include increased desertification; prolonged dry season, shifts in the rainfall patterns; delayed onset and early cessation of rainfall; reductions in the length of the growing season; floods; storms; late establishment of steady rainfall; sudden drought experience; reduced production; and changes in the frequency and intensity of extreme weather conditions, such as drought, significantly influence crop yields [1, 2]. Among these challenges, drought is distinctly a crucial abiotic factor that negatively affects crop plant growth and development worldwide and is perhaps the most important abiotic stress limiting agricultural productivity [3, 4]. Projections have suggested that climate shifts effects will becoming increasingly erratic and exacerbate water deficits, leading to expansion of drought-affected arable land, and by 2050, water shortages are expected to impact 67% of the global population [5, 6]. This problem has profound effects on the world\u0026rsquo;s agriculture and food security, especially in rain-fed dependent agricultural systems [7]. The effects of drought include the impaired growth, disrupted water relations, reduced water use efficiency, and ultimately resulting in decreased crop yield [8]. However, crop varieties exhibit varying levels of resilience to drought stress via several factors [9, 10]. In order to address these challenges, climate-smart agriculture (CSA) mitigation strategies have been identified as viable solutions, one such approach involves the cultivation of resilient crops such as sorghum [11]. The role of sorghum in CSA includes drought tolerance, resistance to pests and diseases, adaptation capability to harsh arid and semiarid regions which is characterized by its extensive roots, waxy leaf coating that minimises water loss, the ability to suspend growth during dry spells as well as resume when conditions improve, the possession of diverse genetic resources, and higher nutritional value attributes [12, 13]. Hence, sorghum holds significant potential and needs to be better explored to mitigating the impacts of climate change. Sorghum [\u003cem\u003eSorghum bicolor\u003c/em\u003e (L.) Moench], a member of the \u003cem\u003ePoaceae\u003c/em\u003e family is the fifth most important cereal crop globally after barley, maize, rice and wheat. In Africa, in terms of yield, it ranks as the third most important cereal crop contributing 26.3\u0026nbsp;million metric tonnes annually, following maize with 96.6\u0026nbsp;million metric tonnes and rice having 37.2\u0026nbsp;million metric tonnes [14]. As a highly valued cereal native to Sub-Saharan Africa, it has been grown for centuries as a major staple food of millions of people in different parts of the tropical and subtropical regions of the world [15]. Similarly, beyond its role as food, sorghum serves as animal feed and industrially, as raw material for the production of alcohol, fiber, fuel, starch, wax, syrup, agar, gluten feed, edible oils, biodegradable packaging materials, solvents, wallboard, fences, and also, in the brewing industry [16, 17]. Researchers have shown that nutritionally sorghum grain is rich in iron, zinc, vitamin B6, vitamin B3 (niacin), magnesium, phosphorus, fibre, unsaturated fats, and protein; gluten free, which makes it a valuable alternative for individuals with wheat allergies ; and some varieties contain high levels of antioxidants, [18]. Studies have revealed that despite sorghum resilience to drought stress, specific stages in its lifecycle such as the early vegetative stage and reproductive stages (pre- and post-flowering) are particularly susceptible to drought stress; therefore, the tolerance ability at these stages is critical to productivity; hence, severe drought stress could lead to crop loss and/or decreased productivity in sorghum [19]. Consequently, the aim of this study was to identify improved drought-tolerant sorghum varieties and subsequently evaluate their agronomic responses to scheduled, severe water stress. The first objective was to investigate the agronomic responses of three improved sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under severe water stress conditions during scheduled water stress at the identified particularly critical stages when sorghum could be susceptible to drought stress. The second objective was to evaluate the distinct varietal agronomic responses of those varieties during scheduled water deficit (moderate and severe stress) at the identified sorghum drought-sensitive growth stages. In this study, we exposed three sorghum varieties with different phenologies and genetic backgrounds to controlled, scheduled drought conditions to investigate the underlying variations in agronomic responses to severe drought.\u003c/p\u003e"},{"header":"Material and Methods","content":"\u003cp\u003eThree sorghum varieties (SAMSORG-44, SAMSORG-47 and SAMSORG-48) were evaluated in this study; these varieties were developed at the Institute of Agricultural Research (IAR), Samaru, Nigeria, and were thus sourced from those locations. SAMSORG 44 is an improved early-maturing cultivar (maturity period\u0026thinsp;=\u0026thinsp;85\u0026ndash;95 days; seed color: white; potential yield: 2.8 tons ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e) developed for the northern Guinea savanna. SAMSORG-47 is an improved late-maturing cultivar (maturity period\u0026thinsp;=\u0026thinsp;120\u0026ndash;125 days; seed colour: yellow; potential yield: 4.8 tons). ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), developed for southern Guinea savanna. SAMSORG-48 is also an improved late-maturing cultivar (maturity period\u0026thinsp;=\u0026thinsp;120\u0026ndash;130 days; seed colour: yellow; potential yield: 4.7 tons). ha\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e), which was developed for southern Guinea savanna [20]. The trial was conducted in a screen house located at the Federal University of Agriculture Abeokuta, Nigeria (07\u003csup\u003e\u0026deg;\u003c/sup\u003e15'N, 03\u003csup\u003e\u0026deg;\u003c/sup\u003e25'E), in 2022 (August - December). The experiment was conducted in plastic pots arranged in a completely randomized design (CRD) with three replications. The study was designed as a 3 \u0026times; 3 factorial experiment with three varieties of sorghum subjected to three soil moisture stress levels at two different stages during the crop cycle. The soil moisture stress levels [well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions] were imposed on all three varieties at 21 days after sowing (vegetative) and at 50% flowering (reproductive) for 2 weeks. The moisture stress was imposed once at a particular stage on all stressed plants except the WW plants. The plants were grown in plastic pots perforated at the base and filled with 30 kg of topsoil, watered to field capacity and allowed to drain. Four seeds of each variety were planted in a pot and subsequently thinned to two seedlings per pot at two weeks after emergence. Poultry manure was applied at planting. Weed control was achieved by hand pulling at weekly intervals. The three soil moisture stress levels were created by moistening the pots with different quantities of water corresponding to 100, 50 and 25% of the soil available water (SAW) determined gravimetrically [21]. Before planting, the soil was maintained at 100% field capacity (FC) via the gravimetric method. The soil moisture stress levels were maintained throughout the experimental period by the periodic application of water as needed. The time to 50% flowering and 100% flowering was recorded, which implies that more than 50% of the plants per variety had at least one open panicle and/or when all panicles had opened. The time to physiological maturity was also recorded. (Plant height was measured via a meter rule; the number of leaves was counted and recorded; stem girth was determined via a digital veneer calliper; and dry matter accumulation in the sampled plants oven-dried to constant weight was measured) at 2-week intervals beginning at 4 WAP. The yield and yield components were determined after the plants were harvested and oven-dried to a constant weight. The height at harvest was determined by measuring from the soil level to the tip of the panicle via a meter rule. Panicle length, panicle diameter and panicle weight were measured and recorded, the threshing percentage was calculated as the threshed seed weight divided by the unthreshed panicle weight and expressed as a percentage, the above-ground dry weight (stover weight) and the seed weight were measured and recorded, and the harvest index was computed as the ratio of the seed weight to the above-ground dry weight. The experiment involved a two-factorial (variety and water stress) CRD with three replicates. Agronomic data were analysed via general analysis of variance (ANOVA) in IBM SPSS version 26. Significant (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05, F test) treatment means of main effects and interactions were separated via Duncan\u0026rsquo;s multiple range test (DMRT) [22].\u003c/p\u003e"},{"header":"Results and Discussion","content":"\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003eEffects of water stress and variety on the phenology of sorghum\u003c/h2\u003e \u003cp\u003eThe effects of water stress and variety on the days to 50% flowering, days to 100% flowering and days to maturity of sorghum are shown in Table I. The phenological development of sorghum was not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by drought. The varieties equally differed not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in their phenological development except in days to maturity (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The maturity days of the varieties increased in the order of SAMSORG 44, SAMSORG 47 and SAMSORG 48 (Table I). A significant water stress \u0026times; variety interaction occurred for days to maturity as well. SAMSORG 44 matured earlier than the other varieties did at all levels of water stress and was not affected by drought stress as much as the other sorghum varieties were (Figure I).\u003c/p\u003e \u003cp\u003e \u003cb\u003eTable I: Phenology of three sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions.\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Taba\" border=\"1\"\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eDays to 50% flowering\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eDays to 100% flowering\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eDays to maturity\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eWater stress (T)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewell-watered\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e119\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emoderately water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e119\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eseverely water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e120\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eVariety (V)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e98 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e128 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e78\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e132 c\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e3.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInteraction\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTXV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\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\u003eIn a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan\u0026rsquo;s multiple range test (DMRT). WAP\u0026thinsp;=\u0026thinsp;Weeks after planting. ns\u0026thinsp;=\u0026thinsp;not significant. ** = Significant at the 1% level of probability.\u003c/p\u003e \u003cp\u003eAmong the varieties, SAMSORG 48 maintained the most conservative water use under drought stress, survived the longest and recovered earliest. Similarly, the varieties matured differently in response to the FSAW dynamics. SAMSORG 44 matured earlier than the other methods did. The earlier maturity could be attributed to the capacity of the variety for early maturity [20], which was, however, not influenced by the imposed drought stress. These sorghum varieties likewise varied in response to FSAW dynamics after drought treatment at the reproductive stage. SAMSORG 44 had the most conservative water use. Our study is consistent with earlier studies [9, 10] that have similarly demonstrated differences in the water-use rate during drought stress in sorghum, reporting that sorghum genotypes adapt different mechanisms in response to drought.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eEffects of water stress and sorghum variety on sorghum growth\u003c/h3\u003e\n\u003cp\u003eThe effects of water stress and variety on the plant height, number of leaves, stem girth and dry matter accumulation of sorghum are shown in Table II. Drought stress did not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affect sorghum plant height except at 4 weeks after planting (WAP), when the plant height significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) varied. Taller plants (66.8 cm) were recorded in the moderate drought-stress (MWS) treatment (Table II). Sorghum plant height was significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected by variety. SAMSORG 48 recorded taller plants (130.1 cm) than the other varieties did, which were comparable at 6 WAP, whereas SAMSORG 44 had the tallest plants (161.1 cm) at 8 WAP (Table II). A significant water stress \u0026times; variety interaction occurred for plant height (P\u0026thinsp;\u0026lt;\u0026thinsp;0.01). At 4 WAP, only the SAMSORG 48 cultivar in the SWS treatment group presented taller plants and was not affected by drought stress as much as the other sorghum varieties were affected. Conversely, SAMSORG 48 had the tallest plant at 6 and 8 WAP at all levels of water stress, whereas the other varieties were not affected by drought stress (Figure II).\u003c/p\u003e \u003cp\u003eWater stress (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and variety (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) did not significantly affect the number of leaves of sorghum plants (Table II). The interaction effect of water stress \u0026times; variety on the number of leaves at 8 WAP was significant. A greater number of leaves were recorded in the SWS treatment for SAMSORG47 and SAMSORG48, and all the varieties were not affected by drought stress.\u003c/p\u003e \u003cp\u003eThe stem girth of sorghum was significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by water stress (Table II). Drought stress reduced the stem girth of sorghum plants at 4 WAP, and the thickest stem girth was measured in the WW treatment (Table II). However, at 6 and 8 WAP, the highest stem girths were recorded in the MWS treatment, and the girths of sorghum plants in the SWS and WW treatments were comparable. Variety significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected sorghum stem girth at 6 WAP (Table II). SAMSORG 48 resulted in greater stem girth, whereas the stem girths of SAMSORG 44 and SAMSORG 47 were comparable. A significant water stress \u0026times; variety interaction occurred for stem girth (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Greater numbers of stem girths were recorded for SAMSORG 48, except at 4 WAP, when SAMSORG 44 presented the thickest stem girth. The varieties were not responsive to drought stress except at 4 WAP, in which stem girth decreased by 13\u0026ndash;21% in response to drought stress.\u003c/p\u003e \u003cp\u003e \u003cb\u003eTable II: Growth of three sorghum varieties (SAMSORG 44, SAMSORG 47, and SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions.\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"No\" id=\"Tabb\" border=\"1\"\u003e \u003ccolgroup cols=\"13\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c4\" namest=\"c2\"\u003e \u003cp\u003ePlant height (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c7\" namest=\"c5\"\u003e \u003cp\u003eNumber of leaves\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c10\" namest=\"c8\"\u003e \u003cp\u003eStem girth (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c13\" namest=\"c11\"\u003e \u003cp\u003eDry matter accumulation (g)\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=\"12\" nameend=\"c13\" namest=\"c2\"\u003e \u003cp\u003eWAP\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eWater stress (T)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewell-watered\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62.6 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e114.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e154.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e11.8 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e14.3 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e17.3 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e8.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e12.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e17.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emoderately water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e66.8 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e114.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e157.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.7 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e14.6 ab\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e21.9 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e7.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e11.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e14.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eseverely water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e60.8 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e116.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e156.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e9.6 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e13.4 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e17.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e8.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e12.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e16.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ens\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\u003ens\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\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eVariety (V)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e107.8 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e161.1 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e13.6 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e18.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e7.9 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e11.9 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e15.4 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e107.0 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e151.3 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e13.8 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e18.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e6.1 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e8.7 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e10.8 c\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSORG 48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e65.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e130.1 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e156.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e10.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e14.9 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e19.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e10.6 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e16.1 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e20.7 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e0.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e \u003cp\u003e0.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ens\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\u003ens\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\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e**\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 \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInteraction\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c9\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c12\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c13\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eT\u0026times;V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ens\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\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c10\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c11\"\u003e \u003cp\u003e**\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 \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"13\"\u003eIn a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan\u0026rsquo;s multiple range test (DMRT). WAP\u0026thinsp;=\u0026thinsp;Weeks after planting. ns\u0026thinsp;=\u0026thinsp;not significant. ** = Significant at the 1% level of probability\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eDrought stress did not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affect sorghum dry matter accumulation (Table II). Conversely, the dry matter accumulation of the sorghum varieties significantly differed. SAMSORG 48 accumulated the driest matter at 4, 6 and 8 WAP (Table II). The interaction effect of water stress and variety significantly affected dry matter accumulation at 8 WAP. Like those of the other sorghum varieties, the dry matter accumulation of SAMSORG 48 plants was greatest at all levels of water stress, and the dry matter accumulation of SAMSORG 48 plants was not affected by drought stress (Figure III). In general, none of the agronomic parameters measured were negatively influenced by drought stress. This is an indication that varieties with the same response potential to severe drought stress conditions. Nonetheless, visible variations were observed in most parameters due to varietal effects, which could be attributed to the genetic capacity of the varieties to exhibit superiority in any specified parameter. The shorter days to maturity of the SAMSORG 44 variety indicates that the variety matured earlier than the other varieties did. The taller plants, thicker stem girth and greater dry matter accumulation of SAMSORG 48 during the growth stage indicate that it has better genetic traits for greater growth. In addition, sometimes higher growth could result in higher yields. The superiority of the seed yield, greater panicle weight, longer panicle length, greater panicle diameter and greater harvest index of the SAMSORG 44 variety over the other varieties is an indication of the greater efficiency of the variety in utilizing the assimilate trans located for panicle development to produce grains.\u003c/p\u003e\n\u003ch3\u003eEffects of water stress and variety on the yield and yield components of sorghum\u003c/h3\u003e\n\u003cp\u003eTable III presents the effects of water stress and variety on the above-ground dry weight, seed yield, harvest index, panicle length, panicle diameter, panicle weight, and threshing percentage of sorghum. Drought stress did not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affect sorghum aboveground dry weight. The sorghum above ground dry weight was significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected by variety. Compared with the other varieties, SAMSORG 47 resulted in higher weights, which were comparable. A significant genotype \u0026times; water stress interaction occurred for aboveground dry weight (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The aboveground dry weight of the three varieties ranged from 40.3 to 44.8 g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e in the WW treatment but did not decrease in the water-stressed plants (45.8\u0026ndash;50.8 g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e). The aboveground dry weight was highest in SAMSORG 47, followed by SAMSORG 48, and lowest in SAMSORG 44.\u003c/p\u003e \u003cp\u003eThe seed yield of sorghum was not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by water stress (Table III). Variety significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected sorghum seed yield (Table III). SAMSORG 44 presented the highest seed yield.\u003c/p\u003e \u003cp\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 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eYield and yield components at the final harvest for three sorghum varieties (SAMSORG 44, SAMSORG 47, SAMSORG 48) under well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"8\"\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 \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTreatments\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAbove ground dry weight (g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eSeed yield (g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHarvest index\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePanicle length (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ePanicle diameter (cm)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003ePanicle weight (g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003eThreshing percentage (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eWater stress (T)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ewell-watered\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e42.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e98.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e17.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e48.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e88.2 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003emoderately water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e45.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e95.9\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e18.4\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e48.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e88.0 a\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eseverely water-stressed\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e47.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e18.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e48.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e86.1 b\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.7\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003ens\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\u003ens\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eVariety (V)\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSOARG 44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43.3 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e45.0 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e105 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e22.0 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e6.3 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e51.3 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e87.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSOARG 47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e48.4 a\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e42.9 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89.2 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e18.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e3.2 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e49.5 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e86.7\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSAMSOARG 48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e43.1 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e38.4 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e89.6 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e13.7 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e4.3 b\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e43.7 c\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e88.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSE\u0026plusmn;\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0.8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e2.3\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e0.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e \u003cp\u003e0.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eF test\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\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\u003ens\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cspan type=\"Underline\" class=\"Underline\" name=\"Emphasis\"\u003eInteraction\u003c/span\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c8\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTXV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e**\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\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 \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eIn a column, means followed by similar letters are not significantly different at the 5% probability level according to Duncan\u0026rsquo;s multiple range test (DMRT). WAP\u0026thinsp;=\u0026thinsp;Weeks after planting. ns\u0026thinsp;=\u0026thinsp;not significant. ** = Significant at the 1% level of probability.\u003c/p\u003e \u003cp\u003eA significant water stress \u0026times; variety interaction occurred for seed yield. The seed yield ranged from 34.8 to 44.5 g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e in the WW treatment and from 37.8\u0026ndash;46.5 g plant\u003csup\u003e\u0026ndash;1\u003c/sup\u003e in the drought stress treatment (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05; Figure IV). Compared with the WW plants, the drought-susceptible plants did not exhibit a decrease in yield, and SAMSORG 44 presented the highest seed yield.\u003c/p\u003e \u003cp\u003eDrought stress did not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affect the harvest index (Table III). Conversely, the Sorghum varieties presented significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) different harvest indices. SAMSORG 44 recorded a higher harvest index than the other varieties that were comparable. The interaction effect of water stress and variety significantly affected the harvest index. SAMSORG 44 presented the highest harvest index at all levels of water stress and was not affected by drought stress as much as the other sorghum varieties were (Figure V).\u003c/p\u003e \u003cp\u003eThe panicle length of sorghum was not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by water stress (Table III). Variety significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected sorghum panicle length (Table III). Among the three varieties, SAMSORG 44 presented the longest panicle. A significant water stress \u0026times; variety interaction occurred for panicle length (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The longest panicles were recorded for SAMSORG 44, and the varieties were not responsive to drought stress.\u003c/p\u003e \u003cp\u003eDrought stress did not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affect panicle diameter (Table III). Conversely, the Sorghum varieties presented significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) different panicle diameters. SAMSORG 44 had the thickest panicle diameter (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e3\u003c/span\u003e). The interaction effect of water stress and variety significantly affected panicle diameter. SAMSORG 44 had plants with the thickest panicle diameter at all levels of water stress and were not as affected by drought stress as the other sorghum varieties were.\u003c/p\u003e \u003cp\u003eThe panicle weight of sorghum was not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by drought. The varieties differed significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in their panicle weights. The panicle weights of the varieties were in increasing order: SAMSORG 44, SAMSORG 47 and SAMSORG 48 (Table III). A significant water stress \u0026times; variety interaction occurred for panicle weight as well. The SAMSORG 44 and SAMSORG 47 panicle weights were greater than those at all levels of water stress, and all varieties were not affected by drought stress.\u003c/p\u003e \u003cp\u003eDrought stress significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected the sorghum threshing percentage. A lower percentage was recorded in the SWS treatment (Table III). The sorghum threshing percentage was not significantly (P\u0026thinsp;\u0026lt;\u0026thinsp;0.05) affected by variety. The interaction effect of water stress \u0026times; variety had a significant effect on the percentage of threshing. Higher threshing percentages were recorded in the MWS treatment for SAMSORG 44 and SAMSORG 47, and all the varieties were not affected by drought stress. The results of this study revealed that drought stress had no significant effect on the phenology, growth, yield or yield components of sorghum. This disproves the earlier report that particular stages of the sorghum lifecycle, such as the early vegetative stage and reproductive stages (pre- and post-flowering), are susceptible to drought stress; hence, severe drought stress could lead to crop yield reduction and decreased productivity [19]. On the basis of the results of the present study, the adaptive ability of these sorghum varieties for severe drought tolerance, even at those identified critical stages, was revealed, indicating that there was a negligible effect of water deficit during the vegetative stage and reproductive stages since the measured parameters of phenology, growth, and yield and yield components of the MWS and SWS plants are comparable to those of the WW crops. Moreover, various researchers have identified four general basic strategies employed as drought resistance mechanisms by drought-tolerant crop plants to mitigate drought stress effects during moisture stress conditions: drought escape, drought avoidance, drought tolerance and drought recovery, although more than one mechanism may be used simultaneously to resist drought [6, 7]. Drought avoidance, drought tolerance and drought recovery might be the mechanisms identified in the present study that were employed simultaneously by the sorghum varieties under investigation. Drought avoidance involves the conservation of water by the plant via a reduction in water loss from the shoots or, alternatively, efficient extraction of water from the soil, which permits a longer growth period in the crop, which results in reduced water use or increased water uptake [23]. Drought tolerance involves the maintenance of a certain level of physiological activities under severe drought stress conditions via gene regulation protocols as well as metabolic pathways to reduce or probably repair the resulting effects of stress, which implies water deficit resistance while maintaining appropriate physiological activities to stabilize and protect cellular and metabolic integrity at the tissue and cellular levels via the accumulation of sugars, polyols, amino acids, alkaloids, etc., to increase their concentration, reduce osmotic potential, and enhance the retention of cell water in response to water stress [24], whereas drought recovery implies the resumption of growth and seed yield after severe moisture stress occurrence, which could cause a complete loss of turgor pressure with leaf dehydration [25].\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study revealed that all agronomic (phenological, growth, yield and yield components) parameters measured were not significantly influenced by severe drought stress. The three sorghum varieties responded differently in terms of FSAW dynamics at both the vegetative and reproductive stages. SAMSORG 48 presented greater growth, whereas SAMSORG 44 presented greater seed yield and yield components at all levels of water stress, and all the varieties were not affected by drought stress at either stage. These varieties are highly suitable for severe drought tolerance. SAMSORG 44 had a comparatively superior performance, as indicated by its relatively high moisture\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthical approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAll methods used in this research complied with the relevant institutional, national, and international guidelines and legislation. In addition, since this study does not involve wild plant materials, hence, any formal identification of plant material was not required.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe raw data have been deposited and/or published in the repository with the dataset identifier Fadeyi, Olasupo James (2024), \u0026ldquo;Agronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress\u0026rdquo;, Mendeley Data, V1, doi: 10.17632/zwgn543vjw.1\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors have no relevant financial or non-financial interests to disclose.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNo funding was obtained for this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; Contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eFadeyi, Olasupo James collected, analysed and interpreted the data for the research work and was the major contributor in writing this manuscript. Fabunmi, Thomas Oladeji was a major participant in the interpretation of the data and contributed in\u0026nbsp;writing this manuscript. Olowe, Victor Idowu Olugbenga engaged in data collection monitoring, data interpretation and contributed in\u0026nbsp;writing this manuscript. All authors read and approved the manuscript.\u0026nbsp;Christopher Olu Adejuyigbe\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003eis the soil scientist who guided in the soil methodology and interpreted the data collected, he proof read and approved the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors appreciate the kind gesture of Mr. P.A. S. Soremi, a Lecturer in the Department of Plant Physiology and Crop Production, FUNAAB, for his support in making the facilities at his disposal available, which were necessary for the success of the project. We also thank laboratory scientists of the same department for providing facility and technical support during the recording of various agronomic measurements.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMenezes, C.B., Saldanha, D.C.., Santos, C.V, Andrade, L.C., J\u0026uacute;lio M.P., Portugal, A.F., Tardin, F.D. (2015). Evaluation of grain yield in sorghum hybrids under water stress. Genetics and Molecular Research. 14: 12675-12683.\u003c/li\u003e\n\u003cli\u003eChadalavada, K.B., Kumari, D.R., Kumar, S. (2021). Sorghum mitigates climate variability and change on crop yield and quality. Planta. 253: 1-19.\u003c/li\u003e\n\u003cli\u003eFarooq, M., Hussain, M., Wahid, A., Siddique, K.H.M. (2012). Drought stress in plants: An overview. In: R. Aroca, ed. Plant responses to drought stress: From morphological to molecular features, 1\u0026ndash;37.\u003c/li\u003e\n\u003cli\u003eFathi, A. and Tari, D.B. (2016). Effect of drought stress and its mechanism in plants. International Journal of Life Sciences, 10(1): 1-6.\u003c/li\u003e\n\u003cli\u003eGupta, A., Rico-Medina, A., Ca\u0026ntilde;o-Delgado, A.I. (2020). The physiology of plant responses to drought. Sci. 368: 266\u0026ndash;269.\u003c/li\u003e\n\u003cli\u003eBegna, T. (2020). Effects of Drought Stress on Crop Production and Productivity. Intl. J. of Research Studies in Agricultural Sciences. 6: 34-43.\u003c/li\u003e\n\u003cli\u003eVerma, R., Kumar, R., Anamika N. (2018). Drought Resistance Mechanism and Adaptation to Water Stress in Sorghum [Sorghum bicolor (L.) Moench]. Int. J. Biores. \u0026amp;Stress Mgt. 9(1): 167-172.\u003c/li\u003e\n\u003cli\u003eFarooq, M., A. Wahid, N. Kobayashi, D. Fujita and S.M.A. Basra. (2009). Plant drought stress: effects, mechanisms and management. Agron. Sustain. Dev., 29: 185-212.\u003c/li\u003e\n\u003cli\u003eGholipoor, M., Sinclair, T.R., Prasad, P.V.V. (2012). Genotypic variation within sorghum for transpiration response to drying soil. Plant Soil 357: 35\u0026ndash;40.\u003c/li\u003e\n\u003cli\u003eMarkos, S., Tamirat, S., Tamirat, S. (2020). Evaluation of improved lowland sorghum (\u003cem\u003eSorghum\u003c/em\u003e \u003cem\u003ebicolor\u003c/em\u003e (L.) Moench) varieties in southern Ethiopia. Cogent Food \u0026amp; Agriculture\u003cem\u003e, \u003c/em\u003e6: 1727624. http://doi.org/101080/23311932.2020.1727624\u003c/li\u003e\n\u003cli\u003eFAO, (2013). Climate Smart Agriculture: A Resource book. 2013\u003c/li\u003e\n\u003cli\u003eHadebe, S.T., Modi, A.T., Mabhaudhi, T. (2017). Drought Tolerance and Water Use of Cereal Crops: A Focus on Sorghum as a Food Security Crop in Sub-Saharan Africa. J. Agr. Crop Sci. 203: 177-191.\u003c/li\u003e\n\u003cli\u003eSamuel, O., Okeyo, S.N., Ndirangu, H., Isaboke, N., Lucy, K.N. (2020). Determinants of sorghum productivity among small-scale farmers in Siaya County, Kenya. African Journal of Agricultural Research. 16(5): 722-731.\u003c/li\u003e\n\u003cli\u003eYahaya, M.A., Shimelis, H., Nebi\u0026eacute;, B., Mashilo, J., Pop, G. (2023). Response of African Sorghum Genotypes for Drought Tolerance under Variable Environments. Agronomy. 13: 557\u003c/li\u003e\n\u003cli\u003eAmal, G., M. S., Hassanein, and Nabila, M. Z. (2018). Grain sorghum as influenced by organic and microcat mix fertilizer. Middle East Journal of Agriculture Research\u003cem\u003e.\u003c/em\u003e 7(3): 1041-1048.\u003c/li\u003e\n\u003cli\u003eAgrama, H.A., Tuinstra, M.R. (2003). Phylogenetic diversity and relationships among sorghum accessions using SSRs and RAPDs. Afric. J. Biotech. 2(10): 334-340.\u003c/li\u003e\n\u003cli\u003eMamoudou H. D, Hurry G, Alfred S, Alphons G.J and Van B. (2006). Sorghum grain as human food in Africa: relevance of content of starch and amylase activities. Afric. J. Biotech 5(5): 384-395.\u003c/li\u003e\n\u003cli\u003eMuui, C.W, Muasya R.M., Kirubi, D.T. (2013). Baseline Survey on factors affecting sorghum production and use in Eastern Kenya. African Journal of Food, Agriculture, Nutrition and Development 13(1): 7339-7357.\u003c/li\u003e\n\u003cli\u003eDevnarain, N., Crampton, B.G., Chikwamba, R., Becker, J.V.W., O\u0026apos;Kennedy, M.M. (2016). Physiological responses of selected African sorghum landraces to progressive water stress and rewatering. South Afr. J. Bot. 103: 61\u0026ndash;69.\u003c/li\u003e\n\u003cli\u003eCGIAR. (2018).3 sorghum varieties released in Nigeria\u003cstrong\u003e.\u003c/strong\u003e https://www.cgiar.org/news-events/news/3-sorghum-varieties-released-in-nigeria. Accessed 16 December 2024.\u003c/li\u003e\n\u003cli\u003eDuncan, D.B. (1955). Multiple Range and Multiple F Test. Biometrics. 11: 1-5.\u003c/li\u003e\n\u003cli\u003eKramer, P.J. (1983). Water Relations of Plants. New York Academic Press, New York.\u003c/li\u003e\n\u003cli\u003eHu, H., Xiong, L. (2014). Genetic engineering and breeding of drought-resistant crops. Annual Review on Plant Biology 65: 715\u0026ndash;741.\u003c/li\u003e\n\u003cli\u003eXiong, L., Wang, R., Mao, G., Koezan, J. (2006). Identification of drought tolerance determinants by genetic analysis of root responses to drought stress and abscisic acid. Plant Physiology 142, 1065\u0026ndash;1074.\u003c/li\u003e\n\u003cli\u003eLuo, L.J. (2010). Breeding for water-saving and droughtresistance rice (WDR) in China. Journal of Experimental Botany 61: 3509\u0026ndash;3517.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"climate change, climate–smart agriculture, drought stress, drought tolerance, Sorghum bicolor, sorghum varieties","lastPublishedDoi":"10.21203/rs.3.rs-5664895/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5664895/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe 13th sustainable development goal emphasises urgent action to combat climate change and its impacts; in this context, continuous evaluation of drought tolerance traits in crops with high climate-smart potential is imperative. The agronomic responses of three improved sorghum varieties (SAMSORG 44, SAMSORG 47, SAMSORG 48) under severe water stress conditions were investigated in a screen house study in 2022 (August\u0026ndash;December) as a 3 \u0026times; 3 factorial experiment in plastic pots arranged in a completely randomized design (CRD) with three replications. Three soil moisture stress levels [well-watered (WW), moderately water-stressed (MWS) and severely water-stressed (SWS) conditions] corresponding to 100, 50 and 25%, respectively, of fractional soil available water (FSAW) determined gravimetrically were imposed at 21 days after sowing (vegetative) and at 50% flowering (reproductive) for 2 weeks. Agronomic (phenological, growth, yield and yield components) parameters measured were not significantly (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) influenced by drought stress. There were significant (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) interactions between water stress and variety. The three sorghum varieties responded differently (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) in terms of FSAW dynamics at both the vegetative and reproductive stages. SAMSORG 44 had a comparatively superior performance, as indicated by its relatively high moisture stress tolerance. These varieties are suggested to be suitable for cultivation under severe drought conditions.\u003c/p\u003e","manuscriptTitle":"Agronomic responses of selected improved sorghum [Sorghum bicolor (L.) Moench] varieties to scheduled water stress","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-19 04:44:37","doi":"10.21203/rs.3.rs-5664895/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"f2b926d7-e08d-47d3-bd55-188a90ead8d8","owner":[],"postedDate":"December 19th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":41742400,"name":"Agronomy"}],"tags":[],"updatedAt":"2025-01-30T09:38:24+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-19 04:44:37","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5664895","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5664895","identity":"rs-5664895","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}