| Using the wheat cultivar Zhoumai 23 as material,
the
re were 10 treatments that were coded as N0, N84, NI68, N252 and N336 (standing
for single nitrogen fertilizer at 0, 84, 168, 252 kg·hm-2 and 336 kg·hm
-2, respectively), and S+N0, S+N84, S+NI68, S+N252 and S+N336 (standing fo
r 5 500 kg·hm-2 straw returning combined with nitrogen fertilizer at the
rates as above). The results showed that, compared with the single N treatments,
the yield of wheat under S+N treatments showed a trend of decrease, but the dif
ference between them was insignificant statistically. Nitrogen fertilizer use ef
ficiency under S+N treatments was 1.6%～9.1% higher than that of N treatments. S
traw returning combined with an appropriate amount of nitrogen fertilizer tended
to decrease N requirement per 100 kg grain. In conclusion, straw returning com
bined with nitrogen fertilizer application produced positive effects on wheat
production, and 252～321 kg·hm-2 was a suitable rate of nitrogen applicat
ion for winter wheat in the experimental area. |