Improving N, P, K content, other properties of soil and system productivity through integrated nutrient management practices in SRI hybrid rice -mustard cropping sequence in Eastern India

Abstract

A field experiment was conducted at Regional Research and Technology Transfer Station of Orissa University of Agriculture and Technology, Bhawanipatna, Kalahandi during the year 2013-14 and 2014-15 to study the effect of integrated nutrient management (INM) practices on yield of hybrid rice grown under system of rice intensification (SRI) during kharif season followed by mustard during rabi season and it's residual effect on different soil properties. Eight treatment combinations comprising of K1: RDF i.e.,120:60:60 kg N:P2O5:K2O ha-1 (1/3rd N each at transplanting (TP), active tillering (AT) and panicle initiation (PI), K2:50 % RDF (1/3rd N each at TP, AT and PI) + FYM 5 t ha-1, K3:75 %RDF (1/3rd N each at TP, AT and PI) + FYM 5 t ha-1 , K4:100 % RDF (1/3rd N each at TP, AT and PI) + FYM 5 t ha-1, K5:100% RDF (½ N at TP, ¼th N at AT, ¼ th N at PI) + FYM 5 t ha-1 , K6:100 % RDF (¼th N at TP, ½ N at AT, ¼ th N at PI) + FYM 5 t ha-1, K7:50% RDF (1/3rd N each at TP, AT and PI) + FYM 10 t ha-1 and K8: FYM 5 t ha-1 + Vermicompost (VC) 2.5 ha-1 + Azospirillum 5 kg ha-1 + PSB 5 kg ha-1 were applied to hybrid rice var. Ajay grown under SRI method during kharif season and during rabi season mustard was grown taking the eight kharif season plots as main plot and three nutrient management practices viz., R1:100% RDF (40:20:20 kg N:P2O5:K2O ha-1), R2: 50% RDF + Azotobacter and R3-control (no fertilizer) in sub-plot and replicated thrice. The results revealed that application of 100% RDF + FYM 5 t ha-1 to rice registered significantly higher grain (7545 kg ha-1) and straw yield (7241 kg ha-1) of rice and higher seed yield (806 kg ha-1), stover yield(1423 kg ha-1), harvest index (36.3%) of subsequent mustard crop and system rice equivalent yield (9629 kg ha-1). Application of 50% RDF with BF to mustard recorded higher soil organic carbon and pH than RDF and control. The decrease in bulk density was more in the plots applied with 50% RDF+10t FYM to kharif rice (1.38 Mg m-3) and 50% RDF + BF to rabi mustard (1.41 Mg m-3). The available N, P and K content of soil increased to 237.6, 17.1 and 374.9 kg ha-1 from its initial value 148.2, 12.7 and 352.4 kg ha-1, respectively, at the end of second year with application of 50% RDF + BF to mustard.