Genotypic difference for drought tolerance in cotton (Gossypium barbadense L.)

This work investigates water shortage effects on fifty cotton genotypes to select tolerant genotypes at two seasons (2021-2022), three water treatments were used: well watered, 50% and 75% water shortage, trials were conducted at Sakha Experimental Farm in split-plot arrangement under RCBD, irrigation treatments occupied main plots and sub-plots contained genotypes, results revealed significant differences among genotypes, water treatments and their interactions, genotypes varied significantly under each treatment and over treatments due to their different genetic potential, water shortage treatments significantly reduced most of studied traits, the reduction increased as water shortage increase, the significant G x T interactions mentioned the potential for selecting some drought tolerant genotypes, seven genotypes (G.3, G.4, G.12, G.17, G.35, G.42 and G.43) were defined as the most tolerant genotypes for both water shortage treatments for cotton yields and can be used in hybridization breeding program to improve cotton productivity under drought conditions, contrarily, the tested genotypes were not tolerant for all fiber traits together and selection must be done for each trait separately, almost all of extra-long staple cotton genotypes were most susceptible to water stress in productivity and fiber quality, selection for tolerance to water shortage stress must be practiced under the stress conditions, GGE biplot analysis for seed cotton yield/plant exhibited five genotypes (G.39, G.1, G.25, G.27 and G.48) as the ideal genotypes with the highest yield and stability across water treatments and the well-watered treatment (control) was the ideal treatment, GGE biplot analysis defined five genotypes as ideal genotypes.