Effect of copper fertilization on plant growth, seed yield, copper and phosphorus uptake in soybean (Glycine max) and their residual availability in Mollisol Barik K.C.1, Chandel A.S. Department of Agronomy, Govind, Ballabh Pant University of Agriculture and Technology, Pantnagar, Uttaranchal, 263145 1 Present address: Department of Agronomy, Orissa University of Agriculture and Technology, Bhubaneshwar 751003
Abstract A field experiment was conducted during the rainy season of 1997 and 1998 to study the effect of copper fertilization on plant growth, seed yield of soybean [Glycine max (L.) Merr.], copper and phosphorus uptake and their residual availability. Sixteen treatment combinations consisted of 4 varieties (‘Bragg’, ‘PK 262’, ‘PK 416’ and ‘PK 1042’) as main plots and 4 copper levels (0, 2.5, 5 and 10 kg Cu/ha) as subplot treatments were evaluated in split-plot design with 3 replications. Application of 2.5 kg Cu/ha significantly increased the number of nodules and their dry weight, dry-matter yield/plant and leaf-area index at 60 days, while leaf-area index increased significantly up to 5 kg Cu/ha. The seed yield did not increase with copper application. However, the interactions between varieties and copper levels revealed that variety ‘PK 416’ at 5 kg Cu/ha gave the highest number of nodules, their dry weight, leaf-area index and dry-matter yield at 60 days, seed yield, pods/plant, seed copper and phosphorus uptake at harvest, while ‘Bragg’ yielded lowest. Copper content in soybean seed was higher than its shoot. Shoot and seed phosphorus content and their uptake significantly increased with 2.5 kg Cu/ha and decreased with 10 kg Cu/ha. Copper application significantly increased the copper availability in soil at harvest, whereas the increase in available soil phosphorus was non-significant in northern Indian Mollisols. Differential response of varieties revealed that ‘PK 416’ showed a trend of increased growth and seed yield, while ‘Bragg showed susceptibility to increasing copper and ‘PK 1042’ and ‘PK 262’ gave intermediate responses. Top Keywords Copper fertilization, Soybean varieties, Growth, Yield, Copper, Phosphorus, Residual availability. Top |