Abstract
Heat stress due to climate change could be a critical factor for plant growth as it disturbs flowering time and reduces the crop yield. Therefore, it is crucial to investigate the performance of crop genotypes under heat stress condition. The present research was conducted to assess heat tolerance in 25 mungbean genotypes. The experiment was performed in randomized complete block design on two sowing dates: normal sowing (39°C/26°C) and late sowing for heat treatment (47°C/30°C). All genotypes showed significant variations for treatments, genotypes, and genotypic × treatment interactions. Significantly positive correlation of plant height (0.73**, 0.44**), number of seeds per pod (0.74**, 0.45**) and 100-seed weight (0.89**, 0.43**) with seed yield was recorded under both control and stress conditions, respectively. Principal component analysis revealed a high contribution of seed yield, yield index, geometric mean productivity, tolerance, stress tolerance index and mean productivity for PC1 and PC2. Cluster analysis revealed that genotypes retained in cluster 1 and 2 could be utilized to combine yield and stress stability indices in breeding programs. Findings from multivariate analysis suggested that MN-98, MN-108, MN-2011, MN-2225, MN-93 and MN-203 are potential cultivars under heat stress. Hence, these genotypes could be used as genetic resources for transferring heat tolerance to elite genotypes that are sensitive to high temperatures.