追氮时期及比例对滴灌冬小麦生长特性及产量的影响

Nitrogen Topdressing Stages and Ratio: Effects on the Growth Characteristics and Yield of Winter Wheat Under Drip Irrigation

为研究不同追氮时期追氮比例对滴灌冬小麦的生长发育及产量的影响,在滴灌条件下,以小麦‘新冬18号’为试验材料,在总施氮量300 kg/hm2条件下,设置5个氮肥追施处理[拔节:孕穗6:4(F1处理)、起身:拔节:开花2:4:4(F2处理)、拔节:孕穗:开花4:4:2(F3处理)、起身:拔节:孕穗:开花2:4:2:2(F4处理)、起身:拔节:孕穗:开花2:2:2:4(F5处理)],研究不同处理对滴灌冬小麦生长特性及产量的影响。结果表明,适当调节氮肥追施时期及比例有利于调节小麦的生长及产量,F4处理能减缓叶片SPAD值的下降速度,还能有效提高小麦千粒重、收获指数、地上部分生物总量,最高产量为F4处理,产量达8016.67 kg/hm2,分别显著高于F1、F2处理6.4%和6.7%(P<0.05)。在本试验条件下,氮肥追施时期以起身、拔节、孕穗、开花期均追肥(F4、F5处理)有利于小麦的生长与产量的提高。

To study the effects of different proportions of topdressing nitrogen at different nitrogen topdressing stages on the growth and yield of winter wheat under drip irrigation, taking’Xindong 18’as the test material,and under the condition of total nitrogen application rate of 300 kg/hm2, we set 5 nitrogen topdressing treatments: the jointing: booting with 6:4(F1 treatment), getting up: jointing: flowering with 2:4:4(F2 treatment),jointing: booting: flowering with 4:4:2(F3 treatment), getting up: jointing: booting: flowering with 2:4:2:2(F4 treatment), getting up: jointing: booting: flowering with 2:2:2:4(F5 treatment). The results showed that: the proper adjustment of the period and proportion of nitrogen topdressing was beneficial to regulating the growth and yield of wheat;F4 treatment could slow the decline of SPAD value, and effectively increase 1000-grain weight, harvest index and aboveground biomass of wheat;the highest yield of F4 treatment was 8016.67 kg/hm2,which was significantly higher than that of F1 and F2 treatments by 6.4% and 6.7%, respectively(P<0.05). In conclusion, nitrogen topdressing at the getting up, jointing, booting and flowering stages is beneficial to the growth and yield of wheat.