Pigment concentration and activity of antioxidant enzymes in zinc tolerant and susceptible chickpea genotypes subjected to zinc stress

Physiological parameters like shoot dry weight, chlorophyll ‘a’, Chlorophyll ‘b’, total chlorophyll, carotenoids, soluble protein content, catalase, peroxidase and superoxide dismutase activities were higher in case of zinc tolerant genotypes as compared to zinc susceptible genotypes at pre and post flowering stages of plant growth. The grain yield of chickpea genotypes was positively and significantly correlated with all the physiological parameters except peroxidase and superoxide dismutase activities. At pre-flowering stage grain yield was positively correlated with catalase activity (r=0.450*) and total chlorophyll (r=0.583**), while at post flowering stage grain yield was positively and significantly correlated with shoot dry weight (r=0.435*), total chlorophyll (r=0.470*), soluble protein (r=0.566**) and catalase activity (r=0.604**). From the above results, it can be inferred that total chlorophyll content, catalase, carotenoids and soluble protein are important contributing parameters towards chickpea production under zinc deficient condition. Hence, these parameters can be used as traits for screening/developing zinc stress tolerant genotypes. On the basis of per cent grain yield response, genotypes, viz. FG 897, BG 1084, CSJ 128, PBG 126 and CSG 9505 were identified as tolerant, whereas BG 372, BGM 535 and BG 256 were identified as susceptible to Zn stress.