Performance of maize (Zea mays L.) hybrids and association of morpho-physiological traits with grain yield under heat stress and optimal conditions

Incessant rise in ambient temperature is threatening the sustainability of maize productions, worldwide. Heat stress resilience has emerged as an important trait in maize hybrids. Twelve maize hybrids along with five commercial checks were evaluated for their yielding ability and to know the association of grain yield with its component traits under heat stress and optimal conditions. Per se performance indicated that RCRMH 10 for days to 50 per cent anthesis, RCRMH 11 for days to 50 per cent silking, RCRMH 3 and RCRMH 2 for test weight and P3436, RCRMH 4 and RCRMH 2 for grain yield per hectare, were found superior across environments. The association between grain yield per plant and days to 50 per cent anthesis, days to 50 per cent silking and anthesis to silking interval were significantly negative, while, positively significant with chlorophyll content (SPAD) at 55 DAS and number of leaves per plant at the genotypic level under heat stress and optimal conditions.