水肥互作对中肥旱地小麦光能、水分利用效率及产量效应的研究

Studies on the Effects of Interactions of Water and Nitrogen Treatments on Light,Water Efficiency and Yield of Rain-fed Winter Wheat

研究了黄土高原半干旱地区中肥旱地小麦三个模拟降水、两种施氮量、两种施肥方式对小麦产量的影响。分析了在不同水肥组合下的光能利用效率、投肥增产效益及水分利用效率，得出了各指标对水肥的反应曲线。研究表明４００～６００ｍｍ降水范围内，随水分投入的增加，光能利用率、水分利用率、氮肥生产效果与产量大幅度提高。不同降水年型投入氮肥的生产效果差异较大，总的趋势是在丰水年型（６００ｍｍ降水），氮肥投入效果显著；欠水年型（４００ｍｍ），亩施１５Ｋｇ尿素增产效果明显，再增加氮肥投入，反而导致减产。

Effects of water,nitrogens and their interactions on dryland wheat were studied in loessPlateau,China. Three rainfalls were simulated under the same natural growing season. Results showed that with the increase of rainfall within the range of rainfall 400-600mm,efficiency of light and water increased,yield increased directly. Effects of rainfall and Nitrogenare impelled each other obviously. Increasing nitrogen amount has a big difference to yield indifferent rainfalls. The trend is that under sufficient water,wheat yield will be increased obviously through increasing nitrogen appropriately ; under insufficient water,wheat yield will beincreased when 15 KG/mu ureas were applied,or yield will be decreased with increasing ofnitrogen over 15KG/mu.