Soil Available Nitrogen and Yield Effect under Different Combinations of Urease/Nitrate Inhibitor in Wheat/Maize Rotation System

In a wheat/maize rotation system, nitrogen (N) accounts for large proportion of basal fertilizer, but soil N loss and the resulting environmental risk simultaneously exist worldwide. This study applied different urease/nitrification inhibitors together with fertilizers investigated their effects on level grain yield. Six stabilizing combinations consisted two urease (HQ NBPT) three nitrification (DCD, DMPP, Nitrapyrin). The treatments supplied reduced, to some degree, conversion rate NH4+ into NO3−, kept content higher in surface soils longer time. Compared CK, A1 treatment 1.5% HQ + 4% DCD well-maintained levels alkali-hydrolyzable NH4+. For example, contents at 0–20 cm layer under were increased by 8.59–41.6% 8.15–14.5% more than respectively. Based entire growth period wheat maize rotation, improved available did not prevent NO3− leaching, especially intensive rainfall season. or Nitrapyrin significantly enhanced crop Specifically, yields A3 (1.5% 0.25% Nitrapyrin) 16.3% 14.3% also promoted intake transport every stage. maximum accumulation was 27% A1, when compared CK. achieved apparent recovery efficiency, agronomic partial factor productivity. Consequently, could improve availability 0–40 layer, which turn use efficiency maize. results suggested that inhibitor combinations, (A1) (A3), optimal agents worthy further study.