Utilization of Resources as a Component of Integrated Nutrient Management Strategy in Tropical Tuber Crops

摘要

Tropical tuber crops like cassava, sweet potato and elephant foot yam have served as major/subsidiary food for a major section of the global human population since time immemorial. Because of the higher biological efficiency manifested in terms of high tuber yields, response of these crops to application of fertilizers and manures is high. Though tuber crops are grown on marginal soils, our experience has shown that the farmers' income can be enhanced substantially through proper utilization of different natural as well as applied resources under integrated nutrient management (INM) practice. Natural resources managed in this strategy include soil, planting material and crop residues; whereas applied resources involve organic manures, chemical fertilizers and biofertilizers. This paper describes a detailed account of the ways in which these resources have been managed efficiently leading to the higher benefit : cost ratio. The low input management technology developed at the ICAR-CTCRI, Thiruvananthapuram by combining the natural as well as applied resources like nutrient use efficient (NUE) planting material; cost-effective organic manure source like green manuring in situ with cowpea; soil test based application of fertilizers including major, secondary and micro nutrients; and use of effective biofertilizers not only effected up to 55% saving in the fertilizer inputs but also raised the farm income with benefit : cost (B:C) ratio up to 4.4:1.