Dissecting Genotype x Environment Interaction and Adaptability for Grain Yield in Irrigated Rice Systems

Abstract

Rice cultivation is widely adapted across diverse agro-climatic zones and serves as a global staple food, supplying up to 75% of caloric intake for nearly 3 billion people worldwide. In Bangladesh, evolving climate patterns are increasingly threatening rice productivity across diverse agro-ecological regions. Therefore, identifying stable, high-yielding genotypes across agro-climatic zones in Bangladesh is essential for sustaining national food security. This study evaluated the yield stability of 10 advanced inbred lines with 2 HYV as checks across 10 diverse agro climatic zones using AMMI and GGE models.  Eight yield-related traits were analyzed, including days to maturity, plant height, number of effective tillers, panicle length, number of filled grains, percent spikelet sterility, 1000-grain weight, and grain yield. Combined ANOVA revealed significant effects of genotype, environment, and GEI on all traits, which were significantly associated with yield. The first two PCs explained 29.8% and 23.5% of variation in AMMI, and 30.66% and 22.79% in GGE. Among the studied genotypes, we found genotype G6 (NGR750-1) was the most stable comparable to the check HYV BRRI dhan89. Stability analysis showed that GEI strongly affects grain yield and the selection of stable genotypes across environments. Further investigation is required to elucidate the adaptive mechanisms of the identified genotype, focusing on physiological and molecular determinants of grain yield across diverse environments. The identified genotype could be used further within the framework of the rice improvement program or released as a high-yielding cultivar following multi-location evaluation.

Bangladesh Rice J.29(2): 17-24, 2025