Inorganic fractionation of nitrogen, phosphorous and potassium as influenced by INM practices in elephant foot yam - black gram system

Abstract

AbstractA field experiment was conducted for two consecutive kharif seasons during 2018-19 and 2019-20 to study the effect of integrated application of inorganic fertilizers and organic manure on fractionation of N, P and K and yield performance of elephant foot yam – black gram cropping system in an acid Alfisol of Odisha. Higher amount of ammoniacal-N and nitrate-N (124.56, 24.19 kg ha-1, respectively), reductant soluble-P (60.16 mg kg-1) and exchangeable K (205.63 kg ha-1) were recorded due to integrated application of FYM + ½ NPK. Available N in the soils influenced by ammoniacal N, nitrate-N and total N and the relationship was found to be positive and significant (r = 0.950**, 0.935**and 0.927**, respectively). Calcium bound P, total P, water soluble P, and Al-P contributed significantly towards the available P pool (r=0.991**, 0.955**, 0.942**, 0.930**, respectively), whereas, available K was contributed significantly with exchangeable K, total K and non-exchangeable K fractions (r = 0.979, 0.937** and 0.927**, respectively). Available N showed positive and significant relationship with starch, total sugars and dry matter (r=0.895**, 0.894**, 0.864**, respectively), whereas iron bound P had significant relationship with starch, total sugars and dry matter (r=0.869**, 0.832**, 0.686**, respectively). In conclusion, the corm yield of elephant foot yam and grain yield of black gram showed highly significant relationship with ammoniacal N, Fe-P and total K and they had been considered as major contributing fractions in respect of N, P and K towards the yield and quality of elephant foot yam – black gram crops.Keywords: Alfisol, INM practices, Elephant foot yam, Yield, Quality, Inorganic fractions