Effect of Nano-Urea Based Nitrogen Management and Herbicide Mixtures on Rhizospheric Dynamics of Wheat for Enhanced Productivity, Profitability and Yield Emission Trade-Offs

As nitrogen and weed management in wheat gains prominence for uplifting its productivity, the exploration of alternative nitrogen and weed management options become a priority. In this regard, an experiment was conducted in split plot design with three replications. In main plot, four nitrogen management options were tested: N1 = control, N2 = 100% Recommended Dose of Nitrogen (RDN), N3 = 50% RDN + 2 spray of nano-urea (SNU) (40 & 60 days after sowing– DAS) and N4 = 75% RDN + 1 SNU (60 DAS). Concurrently, four weed management treatments were studied in subplots: W1 = Ready mix of sulfosulfuron + metsulfuron methyl @ 30 + 2 g a.i. ha^− 1 at 30 DAS; W2 = tank mix of clodinafop propargyl @ 60 g a.i. ha^− 1 + carfentrazone-ethyl @ 20 g a.i. ha^− 1 at 30 DAS; W3 = weed free check and W4 = un-weeded check. The results revealed that 100% RDN outperformed 50% RDN + 2-SNU & 75% RDN + 1 SNU in terms of superior soil microbial activity and wheat root growth parameters, ultimately resulting in the maximum grain & straw yield, profitability along with best yield emission trade-offs. Comparing between the two herbicide mixtures, the tank mix of clodinafop + carfentrazone ethyl surpassed the ready mix of sulfosulfuron + metsulfuron methyl in terms of all the above mentioned parameters.