Yield and physiological responses of mungbean Vigna radita (L.) Wilczek genotypes to high temperature at reproductive stage

A study was conducted to examine the physiological responses and yield of contrasting mungbean genotypes viz, MH 421, MH 318 and Basanti differing in their sensitivity to high temperature raised in earthen pots (30 cm diameter) filled with 5.5 kg of dune sand (Typic Torrispamments) under screen house conditions. High temperature stress was given by manipulating sowing dates i.e. normal (12^th March, 2013) and late (29^th March, 2013) sown. Samplings were done at 3 and 7 days after exposure (DAE) of temperature above 35°C at reproductive stage. Sampling below 35°C temperature was considered as control. High temperature resulted in decreased chlorophyll stability index, chlorophyll and carotenoid contents, relative stress injury and yield. Sensitive genotypes showed large reductions in aforementioned physiological traits. On the other hand, tolerant genotype (MH 421) maintained higher chlorophyll stability index, chlorophyll and carotenoid contents, relative stress injury and yield. After 7 days of exposure to high temperature under late sown, A significant decrease was noticed in genotypes MH 318 and Basanti.