Effect of Sulphur and Cobalt on Yield and Oil Quality of Soybean

摘要

Soybean is an important legume crop, grown for its edible beans and oil. It has very high nutritive value containing 20-22% oil and 40-42% protein alongwith 5% lysine which is mostly deficient in cereals. In addition, it contains good amount of minerals, salts and vitamins. This crop is gaining popularity on accounts of its unique characteristics and has good adaptability towards a wide range of soils and agro-climatic conditions. Soybean is one of the potential crops of north-eastern region and canbe grown alone or intercropped with maize, ragi etc. on slopes as well as in jhumland, terraces and plains. Sulphur (S) is an important nutrient input which promotes the growth, yield and quality of soybean (Sharma and Gupta 2003; Farhad et al, 2010; Tenua et al. 2014). As an important secondary nutrient S helps in synthesis of important amino acids (methionine, cysteine and cystine), chlorophyll and vitamins (biotin and thiamine). It also helps in nitrate reduction and assimilation of nitrogen (N) by root nodule bacteria. Cobalt (Co) is a constituent of cobalamine enzyme and is responsible for formation of leghemoglobin required for N fixation; it also governs the number and size of the root nodules (Yadav and Khanna 1988). Sulphur is essential for microorganisms fixing atmospheric N and also helps in formation of vitamins B,2 in symbiotic microorganisms (Singh et al. 2012). Application of S and P to soils with marginal status improved soybean grain yield and quality (Bhattacharjee et al. 2013). Soybean plays a vital role in build-up the soil fertility by fixing large amounts of atmospheric N through the root nodules, and also leaves incorporated on the ground at maturity. Soybean oil is rich in polyunsaturated fatty acids,including two essential fatty acids, linoleic and linolenic that are not produced in the body.