Nitrogen use efficiency, economic return and yield performance of Pigeonpea [Cajanus cajan (L.) Millsp.] as influenced by nipping and fertility levels

An experiment was conducted to study nitrogen use efficiency in pigeonpea at Research farm, CCS Haryana Agricultural University, Hisar, India having three nipping treatments (no nipping, nipping at just start of branching and nipping at flower initiation) and five fertility levels (control, 20 kg N + 40 kg P2O5/ha, 30 kg N + 40 kg P2O5 /ha, 40 kg N + 40 kg P2O5/ha and 20 kg N + 40 kg P2O5/ha + foliar spray of 2% N immediately after nipping) replicated thrice in split plot design during growing seasons of 2016 and 2017. Nipping at start of branching reduced the plant height, while increased primary and secondary branches, pods/plant and yield over no nipping. Significantly higher total N uptake, protein content, net return, B: C, agronomical NUE, physiologic NUE, agro-physiologic NUE, apparent recovery efficiency, utilization efficiency of N and partial N balance were improved with nipping at start of branching. Among fertility levels, 40 kg N + 40 kg P2O5 / ha recorded significantly higher yield attributes with 39.7 per cent higher seed yield over control. Significantly higher agronomic NUE, physiologic NUE, agro-physiological NUE, apparent recovery efficiency, utilization efficiency of N, partial N balance and NER were recorded with 20 kg/ha as compared to higher nitrogen doses.