Genotype-by-environment interaction of elite heat and drought tolerant bread wheat (Triticum aestivum L.) genotypes under non-stressed and drought-stressed conditions

Abstract

ABSTRACTThe selection of relatively high and stable yielding genotypes is key in wheat breeding programs to improve yield performance under heat and drought-stressed environments. This study determined grain yield response and stability among elite heat and drought tolerant bread wheat genotypes under simulated drought-stressed (DS) and non-stressed (NS) environments to select promising parents for breeding. Twenty-four elite bread wheat genotypes selected from the International Maize and Wheat Improvement Centre (CIMMYT) drought and heat tolerant nursery were assessed under NS and DS conditions using a 7 × 4 alpha-lattice design under rainout shelter (RS) and glasshouse (GH) environments. Grain yield data was subjected to analysis of variance (ANOVA), the additive main effect and multiplicative interaction (AMMI) and genotype and genotype-by-environment (GGE) biplot analyses. ANOVA and AMMI revealed highly significant (p ≤ 0.001) differences among test genotypes (G), environments (E) and G × E interaction effects suggesting differential responses for selection. The GGE biplot explained 83.76% of total variation and aided in selection of high-yielding and stable heat and drought tolerant wheat genotypes such as LM13, LM22, LM95 and LM100. These selections are recommended for breeding for yield gains under heat and drought-stressed environments.