Exploring the usefulness of drought tolerance indices in screening of maize inter-racial derivatives.

Autor: Jaishreepriyanka, R., Ravikesavan, R., Iyanar, K., Uma, D., Senthil, N.
Předmět:
Zdroj: Electronic Journal of Plant Breeding; Sep2024, Vol. 15 Issue 3, p592-603, 12p
Abstrakt: Among all the abiotic factors affecting maize yield, drought stress is the most destructive one. Since drought tolerance is a complicated trait that is difficult to quantify, screening for stress involves measuring the effects of stress on several traits, most notably plant yield. Selection using the drought tolerance indices is an easy way to identify the stable and tolerant genotypes based on yield performances alone. The current study aims to identify suitable maize hybrids with high drought tolerance. A total of 30 maize-teosinte hybrids and 3 checks were raised under optimal and water-stressed environments and were screened using twelve different drought tolerance indices. It was observed that the inter-racial hybrids viz., G24, G27, and G29 were better than the drought tolerant Zea mays ssp. mays check C3 for yield and most of the indices. The indices STI, TOL, GMP, MP, YI, DI, SSPI, K1 STI, and K2 STI were observed to be significantly correlated with yield under stress and optimal environments. Based on the yield both environments, the genotypes were classified under four groups, with Group A consisting of genotypes with high yields under both environments. The indices Stress Tolerance Index (STI), Geometric Mean Productivity (GMP), Yield Index (YI), and Modified Stress Tolerance Index (K2 STI) were identified for their ability to discriminate Group A from the other genotypes and these indices could be utilized to screen for drought tolerance with high yield. Component Analysis revealed two principal components contributing up to 98.15 percent of the cumulative variation. The PCA biplot identified the hybrids viz., G24, G27, G14, G19, and G25 as tolerant ones. Based on the index scores, the hybrids viz., G27, G29, G17, G20, and G24 were identified as the top-ranking genotypes, with high and more stable yields under both stress and optimal environments. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index