PHYSIOLOGICAL AND BIOCHEMICAL STUDIES OF CADMIUM TOXICITY IN GREEN GRAM (VIGNA RADIATA L. WILCZEK) AND ITS FEASIBLE MITIGATION BY MICRONUTRIENT AND HORMONAL TREATMENT

摘要

The experiment has been conducted to evaluate the lethal effect of Cadmium (Cd) and its damage to plant physiological and metabolic process and how best way it can be ameliorated by physiological treatments. Green gram cv. B_1 were taken as study material and grown in pot culture. Treatments were given to plants 21 days after sowing and continued up to 50% flowering stage. Analyses were done at 30, 50 and 60 days after sowing. Growth in respect of root-shoot length (cm), leaf number/plant, leaf area (sq.cm), pod number/plant, pod length (cm), pod weight (g) as well as 100 seed weight (g) were recorded. Biochemically, peroxidase, catalase and chlorophyllase activity were analyzed. Amount of chlorophyll a, chlorophyll b and total chlorophyll were also analyzed. Alternatively, amelioration by GA_3 and Manganese were done to prevail over the toxicity of Cd. From the overall experiments, it was observed that Cadmium had a very toxic effect on green gram by inhibiting the root-shoot growth, leaf area, leaf no., pod characters and 100 seed weight substantially whereas it increased the activity of peroxidase, catalase and chlorophyllase enzyme which indicates that damaging effect of Cd were much pronounced. However, in this investigation, an attempt has been made to establish the role of GA_3 and Manganese as well as their combination for mitigating Cd toxicity. Results have been observed that the damaging effect of Cd can be substantially reduced by application of manganese and GA_3.