Physiological response of greengram under heat stress

Abstract

Greengram is a major grain legume used for consumption from ancient days for its higher protein content. Due to climate change, high temperature stress seriously affects the productivity of legumes and nutritional balance worldwide. Elevated temperature stress during sensitive crop growth stages affects biochemistry of the crops by production of reactive oxygen species which leads to membrane degradation and less physiological activity that affects the yield in greengram. With this background, the experiment was carried out in CO 8 variety to study the biochemical and yield traits of greengram in the temperature controlled growth chambers. Stress was given by raising the temperature up to 2oC and 4oC from the ambient at different growth stages. Results showed, that an increased production of malondialdehyde and H2O2 under elevated temperature than ambient and reduced the photosynthetic rate was also recorded. Antioxidant enzymes viz., Superoxide dismutase and catalase activity were increased under elevated temperature so as to scavenge the free radicals. Yield traits like pod length and weight were drastically reduced in stressed plants. From the results, it was concluded that temperature stress on CO 8 greengram during flowering stage was more critical which caused poor fertility and ultimately resulted in low yield.