Exhaustive cropping systems like wheat/ rice, wheat/cotton, rice/rice etc. have hastened the pace of soil health degeneration. The impact is seen in the plateauing yield levels of major crop-based rotations. At present Indian agriculture is mining nearly 10 million tons of nutrients. In spite of the new technologies continuously emerging on the scenes of action, maintaining the yield growth has become increasingly difficult and costly, mainly due to inefficient input use and declining quality of resource base, manifested by increasing incidence of micronutrient deficiencies, decline in soil organic matter etc.
No matter how successfully the plant potential for higher productivity is expanded, future gains would depend on meeting the nutrient requirement of plants through development of integrated nutrient management systems (IPNS) for sustainable resource management. Recent reports suggest that cereal food deficient in mineral nutrients decreases the IQ of children by 10 points. The potentiating effect of protein-, energy-, mineral nutrient-deficient cereal food may adversely affect about half the population in south Asia. Therefore, promotion of nutrient management through IPNS is an important component of the Indian strategy for food and nutritional security. In the quest for greater productivity, we have a responsibility to promote the use of fertilizers, organics including farm wastes, crop residues, green manure and urban city composts and microbial inoculant to bridge the demand/supply gap of mineral nutrients. The nutrient gap has to be met by enhancing the input use efficiency through development of integrated nutrient management systems for harnessing the positive interactions of crops with growth factors in major production systems in different agro-ecological regions.
In fertilizer consumption statistics, a matter of serious concern is the widening N:P:K fertilizer use ratio. A widening N:P:K ratio indicates an imbalanced fertilizer use. On a macro scale the deviation from the ideal 4:2:1 NPK consumption pattern would suggest that the greater the departure from this ratio, the more the imbalance in the N:P:K ratio. It must be fully recognized that the ideal N:P:K consumption pattern would be different for irrigated, dryland, horticultural and plantation crops. Most organics have N, P and K in proportions such that it is not possible to correct the N:P ratio through their use. Organics having low N and high K (e.g., rice straw) can at best correct the N: K ratio. It is only through the use of enriched phospho-composts that the widening N:P nutrient pattern can be corrected; otherwise, we must promote the use of phosphatic fertilizers.
Was this article helpful?