Nutrient management strategies in rainfed agriculture: Constraints and Opportunities.

Not AvailableThe necessity of increasing food production to meet the demand of the ever-increasing population in India hardly requires any over-emphasis. Estimates suggest that at the current level of production (263 million tonne, Mt), an additional 5 Mt food grain has to be added each year to the national food basket for the next decade or so to feed the increasing population. The total area under cultivation remained more or less constant (at 140-142 Mha) over the past several decades, and there are indications that the agricultural lands are gradually being diverted to accommodate increased urbanization and industrialization. It is unlikely that sizable additional area will be brought in under cultivation in the foreseeable future. Therefore, there is no other viable option than increasing crop productivity per unit area, to meet the future production goals. Maintenance of native soil fertility in the intensively cultivated regions of the country is one of the preconditions of maintaining and improving the current crop yield levels. Intensive cropping systems remove substantial quantities of plant nutrients from soil during continued agricultural production round the year. The basic principle of maintaining the fertility status of a soil under high intensity crop production systems is to annually replenish those nutrients that are removed from the field. Indeed this becomes more relevant in the absence of the measures for adequate replenishment of the depleted nutrient pools through the removal of crop residues from agricultural fields (Sanyal 2014). One would use the term “Nutrient Mining” when the quantity of soil nutrients removed by a crop from an agricultural field exceeds the amount of the nutrient that is recycled back and/ or replenished to the field. Nutrient mining causes a decline in the native soil fertility and may seriously jeopardize future food security of the country. Unfortunately, the concern for nutrient mining in Indian soils is largely limited to the scientific community and has not been integrated adequately with the crop production practices.Not Availabl