江汉平原棉花合理施氮量研究

The Research of Rational Nitrogen Fertilizer Application Rate on Cotton in Jianghan Plain

采用田间小区试验研究了江汉平原棉花合理施氮量。结果表明,在施用90 kg/hm^2 P2O5、180 kg/hm^2K2O和3 kg/hm^2持力硼基础上,利用线性+平台模型得到棉花中高产量水平下的合理施氮量为280 kg/hm^2。在不明显减产的条件下,从提高氮肥当季利用率、尽量降低氮肥投入的角度,可以将氮肥用量降低到240kg/hm^2左右,在此施氮水平下仍然可能通过改进田间管理措施获得高产。因此,江汉平原棉花氮肥减量空间为20~60 kg/hm^2。

Rational nitrogen（N） fertilizer application rate on cotton in Jianghan plain was studied by a field experiment. Results showed that, on the basis of 90 kg/hm^2P2O5,180 kg/hm^2K2 O and 3 kg/hm^2 granubor, and at a medium to high yield,the critical N fertilizer application rate on cotton was 280 kg/hm^2 determined by linear ＋ plateau model. Whereas the N fertilizer application rate could be decreased to around 240 kg/hm^2,if high use efficiency and low investment of N fertilizers were taken into consideration. In this case, high yield was still possible by field management improvement. So the decrement of N fertilizer application rate on cotton was 20~60 kg/hm^2 in Jianghan plain.