Photosynthetic Performance and Drought-Induced Changes in Activity of Antioxidative Enzymes in Different Varieties of Vigna radiata

In the present study, we analysed the photosynthetic performance in five varieties of Vigna radiata, viz. vars RMG 268, K-851, RMG 492, RMG 975 and Anand using chlorophyll fluorescence parameters. We observed that var. RMG 268 tended to reach highest effective quantum yield of PSII [∆F/Fm′], maximum apparent electron transport rate [ETRmax] and saturating photosynthetically active photon flux density [PPFDsat], followed by var. K-851. Thus as judged by its photosynthetic performance, ecophysiologically var. RMG 268 seems to be better adapted to the semi-arid environment of the state of Rajasthan, India. On the contrary, var. Anand was least adapted to its environment as indicated by lowest ETRmax, PPFDsat and ΔF/Fm′ values. The activities of certain antioxidant enzymes of Vigna radiata in response to drought were also examined in var. RMG 268 and var. Anand. The increased activities of antioxidant enzymes, presumed to limit cellular damage, were observed in var. RMG 268. Cellular malondialdehyde content signal indicators of lipid peroxidation were much higher in var. Anand compared to var. RMG 268. These data revealed that var. RMG 268 had high resistance to environmental and drought conditions and thus substantiated our results obtained on the basis of plant performance. © 2018, NAAS (National Academy of Agricultural Sciences).