关键词: 冬小麦, 灌水次数, 宽幅条播, 氮素运转, 产量

Abstract: In order to clarify the water saving mechanism of widespace sowing (WS) winter wheat, a field experiment was carried out at the Wenxi Experimental Demonstration Base of Shanxi Agricultural University from 2017 to 2018. We examined the effects of irrigation frequency \[no irrigation in spring (W0), onetime spring irrigation (W1, jointing water), spring irrigation twice (W2, jointing water, flowering water)\] and sowing pattern \[conventional drilling sowing (DS) and WS\] on soil water consumption, plant nitrogen translocation, yield and benefits of winter wheat. The results showed that, compared with no irrigation in spring, W1 and W2 significantly increased soil water consumption and water consumption intensity at sowing-jointing stage and jointing-anthesis stage, significantly increased nitrogen accumulation at jointing, booting and anthesis stages, and increased pre-anthesis nitrogen translocation, nitrogen accumulation after anthesis and contribution to the grain, significantly increase yield and their components, water use efficiency (WUE) and nitrogen use efficiency (NUE). Compared with W2, W1 reduced soil water consumption and water consumption intensity at anthesis-maturity stage, and significantly increased the contribution of pre-anthesis nitrogen translocation to grains, and the contribution of leaf translocation transfer to the grains; significantly reduced grain number per spike and 1000-grain weight, reduced the yield (but insignificant). Meanwhile, W1 significantly improved WUE by 4%-8% and NUE by 5% under the condition of WS, significantly reduced soil water consumption and water consumption intensity of anthesismaturity stage compared with DS, and increased pre-anthesis nitrogen translocation amount, nitrogen accumulation amount after anthesis and their contribution to grains, and significantly increased grain number per spike, yield, and WUE. Under the conditions of different irrigation frequencies and sowing methods, yield was closely related to nitrogen translocation amount of the stem+sheath, spike+glume before anthesis, and nitrogen accumulation after anthesis. The WUE and NUE were more closely related to the nitrogen translocation amount of the stem+sheath. Compared with irrigation at both jointing and flowering stages, irrigation at jointing reduced post-anthesis soil water consumption and increased preanthesis translocation of plant nitrogen to grains, reduced the number of grains per ear and 1000-grain weight, but yield decline was not obvious, WUE and NUE were improved, and with supporting of wide space sowing, increased production by 16%-48%, income by 39%-76%, and output-input ratio by 22%.

Key words: winter wheat, irrigation times, wide space sowing, nitrogen translocation, yield.