限水减氮对高产麦田群体动态和产量形成的影响

为解决河北省水资源匮乏和麦田施氮量偏多问题,于2013~(-2)014和2014~(-2)015年度,在河北省石家庄市藁城区分别设置限水灌溉的单因素试验和限水减氮的二因素裂区试验,研究了限水减氮对河北省高产麦田群体动态和产量的影响。结果表明,在2013~(-2)014年度,限水灌溉处理(拔节期45mm、开花期30mm、灌浆期30mm,春季总灌水量105mm)与节水灌溉对照(拔节期60mm、开花期60mm,春季总灌水量120mm)间小麦叶面积指数、光能截获率、生物产量、穗数和穗粒数差异均不显著;限水灌溉的千粒重显著增加,籽粒产量为10 081.08kg·hm~(-2),水分利用效率为27.98kg·hm~(-2)·mm-1。在2014~(-2)015年度,限水灌溉处理中W3处理(拔节期37.5mm、开花期15mm、灌浆期15mm,春季总灌水量67.5mm)的叶面积指数、光能截获率与节水灌溉对照(拔节期67.5mm、开花期67.5mm,春季总灌水量135mm)无显著差异,穗数和穗粒数有所降低,但千粒重显著增加,籽粒产量8 903.70kg·hm~(-2),比节水灌溉对照减产7.95%,生物产量降低7.15%,但水分利用效率和灌水利用效率分别提高9.28%和84.10%,且未显著增加0~140cm和0~200cm土层贮水的消耗,是本试验条件下保证高产高效的最佳限水灌溉模式。120、180和240kg·hm~(-2)的3个施氮水平间各指标差异均不显著。综合节水高产和减氮增效的现状,以小麦拔节期灌水37.5mm、开花期15mm、灌浆期15mm的灌溉模式结合生育期施N 120kg·hm~(-2)为本试验条件下的最优限水减氮组合。

Effect of Limited Irrigation and Reduced Nitrogen on Population Dynamics and Yield Formation in High-Yielding Wheat Field

Because of serious water shortage and excessive nitrogen (N) applications in Hebei province,the effects of limited irrigation and reduced nitrogen on population dynamics and yield formation in high-yielding field have been studied to provide technical support for sustainable production,high yield and high water-nitrogen use efficiency of winter wheat.Field experiments were carried out during growing seasons in 2013-2014 and 2014-2015,at Gaocheng county in Hebei province,with a winter wheat variety Shimai 18 as material.In 2013-2014,single-factor experiment of limited water with two irrigation ways was designed,including water limited treatment(WL: irrigation of 45 mm at jointing stage,30 mm at anthesis stage,and 30 mm at grain filling stage) and water saving treatment(WS:irrigation of 60 mm at jointing stage,and 60 mm at anthesis stage).In 2014-2015,a split plot experiment with two factors was conducted including three water limited treatments (W1,W2,W3: total irrigation amount 67.5 mm),and one water saving treatment as control(WCK,irrigation 67.5 mm at jointing stage,and 67.5 mm at anthesis stage),and three nitrogen fertilization levels were 120 kg·hm^-2,180 kg·hm^-2 and 240 kg·hm^-2.The results showed that there were not significant difference in leaf area index,light energy interception rate,biological yield,spike number,and grain number per spike between WL and WS in 2013-2014.The 1 000-grain weight of WL increased significantly; the grain yield was 10 081.08 kg·hm^-2;and the water use efficiency was 27.98 kg·hm^-2·mm^-1.In 2014-2015,there was not significant differences in leaf area index and light energy interception rate between W3 (50% reduction in irrigation amount) and WCK.The spike number and grain number of W3 were decreased,but the 1 000-grain weight was increased significantly.The grain yield of W3 was 8 903.70 kg·hm^-2,which was 7.95% lower than that of WCK; meanwhile,the biological yield was 7.15% lower than that of WCK.However, the water use efficiency and irrigation use efficiency of W3 were increased by 9.28% and 84.10%,respectively; and this did not increase the consumption of soil water storage in 0-140 cm and 0-200 cm layers.Therefore,the best water limited irrigation model was W3,ensuring high yield and high efficiency under this experiment condition.There was not significant difference in all indices among three nitrogen application treatments.Above all,the optimal combination was the irrigation model(irrigation 37.5 mm at jointing stage,15 mm at anthesis stage,and 15 mm at grain filling stage) with 120 kg·hm^-2 N application during the whole wheat growth period.