Evaluation of heat stress tolerance in wheat (Triticum aestivum L.) genotypes using stress tolerance indices in the western region of Nepal

Abstract

Heat stress is the major constraint for wheat production causing significant drops in the yield and potential productivity making it difficult to achieve the target yield by 2030, increasing food insecurity in Nepal. The main aim of the study is to help plant breeders to select appropriate heat stress-tolerant indices for increasing wheat yield by coping with the major problem of heat stress. The experiment holds the study for three years at the Institute of Agriculture and Animal Science (IAAS), Paklihawa campus. The experimental trial was of alpha-lattice design with 5 blocks and 4 plots. There were in total of 2 replications each of 20 genotypes. MP (Mean Productivity) had the highest strong correlation with the stress tolerance indices followed by STI (Stress Tolerance Index) for all three years, whereas YSI (Yield Stability Index) had the lowest tolerance index with a negative correlation for the years 2019 and 2021. The selection of MP and STI is encouraged for the production of heat-stress-tolerant varieties for high-yielding with tolerance.