The Effect of N Fertilizer Placement on the Fate of Urea-(15)N and Yield of Winter Wheat in Southeast China

A field micro-plot experiment using nitrogen isotope ((15)N) labeling was conducted to determine the effects of placement methods (broadcast and band) and N rates (60, 150 and 240 kg ha(–1)) on the fate of urea-(15)N in the wheat–soil system in Guangde County of Anhui Province, China. N fertilizer applied in bands increased grain yield by 15% compared with broadcast application. The N fertilizer application rate had a significant effect on grain yield, straw yield and aboveground biomass, as well as on N uptake and N concentration of wheat. The recovery of urea-(15)N was a little higher for broadcast (34.0–39.0%) than for band treatment (31.2–38.2%). Most of the soil residual N was retained in the 0–20 cm soil layer. At the N rates of 60 and 240 kg ha(–1), the residual (15)N was higher for band (34.4 and 108.7 kg ha(–1), respectively) than for broadcast application (29.6 and 88.4 kg ha(–1), respectively). Compared with broadcast treatment, banded placement of N fertilizer decreased the N loss in the wheat–soil system. Band application one time is an alternative N management practice for winter wheat in this region.