Evaluating Drought Tolerance and Yield Stability of Sorghum Genotypes for Sustainable Agriculture in Sohag, Egypt

Abstract

ABSTRACTThe major problem in the cultivation of sorghum in the Egyptian agricultural system includes arid climate and water shortage. Thus, the present study was undertaken to investigate the effect of drought conditions on the productivity of 21 different sorghum (Sorghum bicolor L.) genotypes at Sohag, Egypt. A set of drought tolerance metrics employed in the present study were Tolerance Index (TOL); Mean Production (MP); Sensitivity to Drought Index (SSI); Stress Tolerance Index (STI); Geometric mean performance (GMP) and Harmonic mean of yield (HARM). A field‐controlled experiment was conducted on the two growth seasons (2021 and 2022) concerning the impact of different drought levels on (ET0 = 0.8, 0.6 and 0.4) Grain Yields (GY) and Water Use Efficiency (WUE) for the various studied sorghum genotypes. Principal Component Analysis (PCA) was also conducted on the obtained data of the different yield parameters with the aim of identifying the most effective tolerance indices related to the different genotypes of sorghum under both conditions, optimal and stressed. Drought tolerance varies among different sorghum varieties, which, by their genetic and physiological nature, possess efficient stomatal regulation and deep‐rooted systems, enhancing water conservation and physiological functions and hence higher WUE. These are mainly influenced by environmental conditions, such as soil type and moisture levels in the region of Sohag, where such genotypes may exhibit different performances regarding drought stress. It was observed that Giza‐15 and Hybrid Sh1 were among the high performers under well‐irrigated conditions, and L38 was outstanding during a severe drought in terms of WUE. Therefore, proper genotype selection depends on the irrigation strategy. Hence, the Sohag region presents a good opportunity for further improvement of drought tolerance through designed selection and hybridization activities in sorghum breeders, and this contributes to climate‐resilient cultivars by addressing the present agricultural challenges and food security for the present world. Emphasis will be placed by breeders on the development of arid‐condition‐adapted genotypes and the development of models that can be applied within comparable climates to boost productivity and sustainability for those farmers dependent on this vital crop.