Zinc Induced Variations in Dry Matter Production, Partitioning and Yield of Mungbean (Vigna radiata L.) under Water Stress

A field experiment was conducted during rabi season of 2017-18 at Agricultural College Farm, Bapatla to study the effect of seed pre - treatment and foliar application of zinc on dry matter production, partitioning and yield of mungbean under water stress. The experiment was laid out in a split plot design with three replications consists of two main treatments viz., no stress i.e. control (M0) and stress from flowering stage (i.e. from 30 DAS) up to harvest (M1) and seven sub-treatments viz., no zinc application (S0), seed treatment with 0.05% and 0.075% ZnSO4 solutions for 5 hrs before sowing (S1 and S2), foliar spray of 300, 400 and 500 ppm ZnSO4 at 30 DAS (S3, S4 and S5) and water spray at 30 DAS (S6). The results showed that leaf, stem, reproductive parts, total dry matter and seed yield was decreased by 23.0, 23.3, 15.3, 18.7 and 33.6 per cent, respectively in the plants that were subjected to stress from flowering stage over control plants. Foliar zinc spray @ 500 ppm at 30 DAS increased the leaf, stem, reproductive parts dry matter, total dry matter and seed yield by 24.6, 24.8, 20.9, 22.5 and 55.2 per cent, respectively, over untreated plants. Normal irrigated plants sprayed with zinc @ 500 ppm (M0S5) recorded the highest mean values of above parameters and the lowest mean values were recorded by the stressed plants with no zinc application (M1S0). Under water stress, mungbean plants sprayed with zinc @ 500 ppm at 30 DAS (M1S5) increased the leaf, stem, reproductive parts, total dry matter and seed yield by 17.6, 16.4, 23.9, 21.3 and 42.0 per cent, respectively, over unsprayed plants (M1S0).