Sulphur in Soils and Plants: An Overview

In India food demand is increasingly doubled due to calorie consumption of fast growing population rate. For achieving and sustaining a high level of food production, especially in agriculture, soil must be regularly replenished with a balance of crop nutrients, like macronutrients, secondary nutrients and micronutrients. Sulphur (S) comes under secondary nutrients after nitrogen, phosphorus and potash (potassium) at number four as an essential nutrient. It exists in group 16 and period 3 with a molecular weight of 32 in the periodic table. Naturally S occurs as an element found in many minerals like iron pyrites, galena, gypsum and Epsom salts. In Igneous and Sedimentary rocks S occurs as sulphides and in soil it is also present as organic compounds also in industrial wastes, sea water as well as gaseous emission in the atmosphere. Under temperate conditions it assumes that more than 95% of total S in soil is present in the organic matter due to low decomposition rate. In plants, sulphur plays an important role in protein synthesis.