Impact of precision nitrogen management practices on nitrogen use efficiencies and nitrogen balance in emmer wheat (Triticum dicoccum L.)

Blanket application of recommended dose of nitrogen fertilizers leads to over or under fertilization. There is need to synchronize the N fertilizer application with plant demand. Field experiment was undertaken at Main Agricultural Research Station (MARS), University of Agricultural Sciences, Dharwad during rabi season of two consecutive years (2020-21 and 2021-22) to assess the nitrogen use efficiencies and nitrogen balance in the soil under precision nitrogen management compared to fixed time N application. Experiment was laid out in RCBD with thirteen treatments (Control, N-Omission, RDN, LCC, SSNM, STCR and NE) and three replications. On the basis of two year pooled results showed that nitrogen management through recommended dose of nitrogen recorded significantly higher NUE, AE_N, PE_N and PFP_N (60.1%, 30.2 kg kg^-1, 35.2 and 38.4 kg kg^-1, respectively). However, higher RE_N was observed in basal application of 30 kg N ha^-1 along with top dressing of 20 kg N ha^-1 through leaf colour chart ≤ 5 (87.0%). The nitrogen balance sheet showed negative nitrogen balance in all the treatments during both the years due to decline in nitrogen content and uptake in grain and straw.