| The influences of N fertilizer and its combination with different crop straws on the biomass, grain yield and nitrogen uptake of winter wheat were researched with pot experiment. There were eight treatments in the study：no fertilizer (CK), urea (U, 150 mg·kg-1 soil), urea+soy
bean straw (UB), urea+maize straw (UM), 120% urea+maize straw (120%UM), 110% urea+soybean straw+maize straw (110%UBM), 100% urea+soybean straw+maize straw (100%UBM) and 80% urea+soybean straw+maize straw (80%UBM), in which the application rates of soybean straw and maize straw were equally 2 g·kg-1 soil. The results showed that, at returning green stage, the wheat biomass in the U trea
tment was significantly higher than that in the treatments of urea combined with different straws; at harvest stage, the wheat biomass in the treatments of urea combined with different straws was higher than that in the urea treatments with the same application rate, however, the difference was not significant. The grain yield in both the UM treatment and UBM treatment was higher than that in the
U treatment. There was no significant difference of grain yield between the 80%UBM treatment and U treatment. The nitrogen use efficiency in the treatments of urea combined with single straw was generally higher than that in the treatments of urea or urea combined with double straws. It was concluded that the application of urea combined with straw could increase the biomass and grain yield of wheat as well as the nitrogen use efficiency. |