English

Abstract

Drought is a significant abiotic stress that negatively impacts plant growth and can lead to substantial crop yield losses. Our study aimed to establish selection criteria for 200 spring-wheat (Triticum aestivum L.) genotypes exposed to three different field-capacity (FC) levels (100%FC, 50%FC, 25%FC) in a growth chamber (seedling traits) and in the field under withholdirrigation conditions (yield traits). Variance, correlation, and principal component analysis (PCA) was performed to identify genotypes with high tolerance to drought stress. The stress induction significantly affects morphophysiological traits i.e., root length, root weight (fresh, dry), fresh shoot weight, relative water contents and root shoot ratio in spring wheat genotypes at seedling stage. The traits flag leaf area, spike weight, grain weight/spike, biological and grain yield were interlinked and strongly influenced by drought in the field. The mean grain yield performance decreased from 21.85 g to 19.46 g under variable water regimes; however, the differences in harvest index and spikelets/spike were not significant. Among the tested genotypes, 9970 and 36-Eswyt-42 showed better root architecture development, leaf water management system, biological yield (66.07 g, 56.23 g) and grain yield (27.47 g, 28.78 g), respectively. The traits we identified may serve as an indirect selection index to enhance current semi-arid wheat germplasm and develop high-yielding drought-tolerant lines in advanced generations. Keywords: Mini core collection, Seedling and yield traits, Selection criteria, Variability analysis