Influence of Calcium and Magnesium on Growth Rate and Antioxidant Responses of Glycine Max Seedlings Grown under Water Deficit and Waterlogged Conditions

Standard procedures were used to determine the influence of calcium and magnesium on growth rate and antioxidant responses of Glycine max seedlings grown under water deficit and waterlogged conditions. The results of the 3 – week old seedlings subjected to 14 days growth under water stress conditions revealed significant decrease (P>0.05) in growth indices (number of leaf, height difference and relative water content) in water deficit and waterlogged seedlings. However, malonaldehyde and antioxidants (superoxide dismutase, catalase, ascorbic acid and vitamin E) significantly increased (P>0.05) in the water stressed samples mostly water deficit seedlings when compared to control group grown under normal condition. In the present study, water supply below and above plant consumptive level for a minimum period of 14 days resulted in generation of reactive oxygen species, peroxidation of lipid and release of defensive mechanism such as endogenous enzymatic and non – enzymatic antioxidants. The macro – nutrients (magnesium and calcium) at the concentration of 40 mg/L mostly magnesium played defensive, compensatory and survival roles in the growth and recovery of soyabean seedlings from water stress effects. Fortification of these macronutrients in agricultural chemicals and adoption in semi arid or arid regions is hereby recommended