Response of Soybean to Phosphorus and Boron Fertilization in Acidic Upland Soil of Nagaland

摘要

Soybean is an important global crop and has very high nutritional value containing 40-45% protein and 18-22% oil. This crop is gaining popularity on account of its unique characteristics and adaptability to various agro-climactic conditions of the Indian soils. Soils of Nagaland are acidic in nature and low in available phosphorus (P) and boron (B). Low availability of phosphorus in these soils is due to fixation of P by Fe and Al oxides. Soybean requires relatively large amounts of phosphorus than the other crops (Laltlanmawia et al. 2004). Adequate supply of phosphorus in early stage of plant growth is important for the development of roots as well as for seed formation and yield. Soybean, being a leguminous crop, builds up the soil fertility by fixing large amounts of atmospheric nitrogen through root nodules. Deficiency of boron has been reported in the acidic upland soils of Meghalaya because of coarse textured and leaching (Takkar 1996) and has become critical for crop productivity. Boron isnecessary for the translocation of sugars, starches, phosphorus, etc and helps in the absorption of nitrogen and formation of nodules (Singh et al. 2006). Soybean requires an adequate supply of available boron, especially during flowering and seed development. Considering the importance of P and B as limiting nutrients in acidic upland soils of Nagaland, an attempt was made to study the influence of levels of phosphorus and boron fertilization on yield, nutrient uptake and protein content of soybean.