Intensive agriculture,use of S-free fertilisers,removal of crop residues and rising crop requirements due to increasing productivity levels have heightened the S demand in soil fertility management and are increasingly becoming major constraints to augment and sustain agricultural production.Soils in nearly 250 districts of the country have varying degree of S deficiency.Sulphur requirements of oilseed crops are highest followed by pulses,forage crops and cereals.Significant response to S application has been reported in all the soils in different crops and the magnitude of response varied with soil type,available S status,crop and S source.Sulphur application also improved protein and oil content and many other quality parameters of commercial and nutritional importance.In general,application of 20 to 50 kg S/ha proved beneficial to first crop as well as succeeding crops in various cropping systems in different soil types.The critical level of soil S varies from 8 to 30mg/kg depending on the analytical method,soil and crop.If a field is known to be deficient in S,the best course is to include atleast one S-containing fertiliser in the basal dose so that S requirement is met at the beginning of crop season.Elemental S and pyrites can also be used a source of S by applying 2-4 weeks prior to planting.The negative S balance in Indian agriculture is a matter of great concern for achieving future targets of production on a sustainable basis.The time has come to recognize S as a critical nutrient input and include it in package of practices as a recommendation to the farming community.Simultaneously,there is also need to intensify research on all aspects of S nutrition of crops and cropping systems in various soil types and agroecological regions of the country.
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