调亏灌溉对新疆滴灌春小麦土壤水分、硝态氮分布及产量的影响

2017年和2018年在北疆滴灌春小麦栽培中,额定施氮量为纯氮300kg/hm2,设置3个调亏灌水量(水分不调亏E1:100%ET0;水分中度调亏E2:80%ET0;水分重度调亏E3:60%ET0)和2个小麦品种(水分敏感型X1:新春22;水分不敏感型X2:新春44),灌溉频率为7天1次。研究不同处理对滴灌春小麦土壤水分、硝态氮分布及产量的影响。结果表明:(1)水分重度调亏(E3)可以缓解0—40cm土壤水分和土壤硝态氮向深层流失,减少作物耗水量,提高水分利用效率。(2)新春22和新春44在土壤质量含水量、土壤硝态氮含量指标上无显著的品种间差异,小麦品种对于土壤理化性质的影响较小。(3)在水分中度调亏(E2)处理下,新春44(X2)能在节约大量灌水同时,提高水分利用效率,保持最适的氮素营养指数(NNI),进而使产量得到了显著的补偿,而新春22(X1)通过中度和重度调亏不能使产量得到有效的补偿。(4)在同一灌溉频率、施氮量水平下,品种对滴灌春小麦水分利用效率的影响大于调亏灌溉水平对滴灌春小麦水分利用效率的影响。(5)水分不敏感型品种新春44(X2)更适合在北疆地区采用调亏灌溉模式生产,综合考虑氮素营养指数(NNI)、耗水量、水分利用效率及产量,其最适的调亏灌溉水平为E2。

Distribution and Yield of Spring Wheat Under Drip Irrigation in Xinjiang

In 2017 and 2018, a field experiment with three regulated deficit irrigation amounts (non-deficit E1:100% of ET0, moderate deficit E2:80% of ET0, severe deficit E3:60% of ET0) and two wheat varieties (water-sensitive type X1:Xin Chun 22, water-insensitive type X2:Xin Chun 44) were conducted with drip irrigation for spring wheat in northern Xinjiang. The same nitrogen level of 300 kg/hm² and same irrigation frequency of one irrigation every 7 days were implemented. The soil moisture, nitrate nitrogen distribution and yield of spring wheat were studied. The results showed that:(1) These water deficit (E3) could alleviate soil water and nitrate nitrogen loss from 0-40 cm to the deep, it also reduced crop water consumption and improved water use efficiency. (2) There was no significant difference in soil mass moisture contents and soil nitrate nitrogen contents between Xin Chun 22 and Xin Chun 44, and wheat varieties had little influence on soil physical and chemical properties. (3) In moderate water deficit (E2), Xin Chun 44 (X2) saved a lot of water, and simultaneously, it improved water use efficiency and maintained the optimum nitrogen nutrition index (NNI).And consequently, the output was significantly compensated. But Xin Chun 22 (X1) could not be effectively compensated by moderate and severe water deficit. (4) With the same level of the nitrogen application and irrigation frequency, the wheat varieties had greater effects than the levels of regulated deficit irrigation on drip irrigation water use efficiency of spring wheat. (5)Taking into account NNI, water consumption, water utilization efficiency and yield, Xin Chun 44 (X2) was more suitable plant with regulated deficit irrigation model in northern Xinjiang, and its optimal regulated deficit irrigation treatment was E2.