Response of cotton genotypes to water-deficit stress using drought tolerance indices and principal component analysis

Abstract

Background Drought impacts on cotton cultivation and production are expected to worsen as a result of global warming and water-deficit stress. Drought tolerance indices and PCA analysis were used to evaluate drought stress responses in eleven cotton genotypes and fifteen indices' ability to identify drought-tolerant genotypes under normal and drought circumstances. Results Seed cotton yield (Kentar/Feddan) was significantly affected by genotypes, years, and their interaction (p ≤ 0.05 or 0.01) under normal and water-deficit stress conditions, according to the combined ANOVA. Except for error variance, all genetic parameters studied for seed cotton yield were higher under normal irrigation conditions than under water-deficit stress conditions. According to PCA analysis, The STI, MP, GMP, HM, ATI, SSPI, and TOL are suitable indicators and were similar in their ability to screen, rank, and detect tolerant genotypes, due to positive correlations among each other and also the highest association with seed cotton yield in both irrigation conditions. The genotypes G4, G9, and G10 (Group A) seemed to be the most drought-tolerant and cotton productive based on mean performance, GxY heatmap analysis, drought tolerance indices, and PCA analysis. Conclusions The results of our study, drought tolerance indices and PCA could be useful and appropriate for studying drought tolerance mechanisms and cotton yield improvement in Egypt.

Advancing Heat Tolerance in Cotton through Integration of Multiple Stress Tolerance Indices and Multivariate Analyses

“…The HM index revealed that the G15, G16, G19, G3 and G7 are heat tolerant, while the G23, G21 and G12 were identified as heat-sensitive genotypes. Our results were in agreement with the findings of (Yehia, 2020). The G15, G16, G3, G19 and G7 exhibited higher STI index values and were declared heat resistant and high yield genotypes.…”

“…The SSI index showed that the G7, G21, G15 and G8 were the most heat tolerant genotypes, whereas the G12, G14, G2, G17 and G5 were the most heat susceptible genotypes. Different studies suggested that SSI is used to determine stress-tolerant cotton genotypes (Anwar et al, 2011;Yehia, 2020). The SSI recognizes only those cultivars having the least differences under normal and stress conditions (Fischer and Maurer, 1978).…”