Abstract

Terminal heat stress poses a significant challenge to wheat production in Bangladesh, especially under late-sown conditions. The rise in temperatures during this period leads to a shortened grain-filling phase, ultimately resulting in decreased yields. This research investigated to assess and pinpoint heat-tolerant wheat genotypes by employing multi-environment trials, which were analyzed using the AMMI and GGE biplot models. A total of twelve wheat varieties were evaluated across three distinct environments: optimum conditions (E1), moderate stress (E2), and terminal heat stress (E3) and the assessment focused on eight agronomic traits. Significant genotype × environment interactions were detected for all traits, highlighting the need for stability assessment. The AMMI 1 biplot effectively distinguished between the main effects of genotypes and their interaction effects, allowing for the identification of genotypes that exhibit both high average performance and adaptability. A better way to differentiate stable performers was possible by AMMI 2, which further clarified the interaction patterns. Among the varieties, BARI Gom 25 (G2), BARI Gom 33 (G6), BARI Gom 26 (G3), and Pavon (G12) were best, according to the Stress Tolerance and Susceptibility index, AMMI, GGE biplot (Which-won-where), Mean vs. stability, Ranking genotype approaches, since they combined above-average yields with stability in both stress and non-stress conditions. The inverse was also true for several genotypes; they showed excellent performance but bad stability. The consistent performance, especially under terminal heat stress, shows that BARI Gom 25 (G2), BARI Gom 33 (G6), BARI Gom 26 (G3), and Pavon (G12) might be used as breeding parents for climate-resilient wheat varieties that are suitable for agro-ecologies in South Asia. A strong framework for choosing stable, high-yielding genotypes in the face of climate change is provided by this combined AMMI-GGE strategy.

Key words: Heat-tolerant wheat genotypes, Multi-environment trials (METs), Stable high-yielding varieties, Stress tolerant and susceptible varieties.