旱地麦田水肥关系及对产量的影响试验研究

用微区隔离遮雨棚法研究结果分析回归得出，氮肥用量、磷肥用量、供水量与冬小麦产量之间关系。固定肥料用量，在试验供水范围内水分和小麦产量呈近似直线关系；固定供水量，施肥量和小麦产量呈抛物线关系。氮肥用量和供水量之间有明显的正交互作用，磷肥用量与供水量之间交互作用不明显。大田不同降雨年份试验结果表明，施肥增产效果是降雨多＞降雨中＞降雨少的年份，在蓄墒期、生育期降雨量为355、411和523 mm的低、中、高降雨年份，冬小麦达最高产量时的氮、磷肥用量分别为每hm²施N 64.5 kg、P₂O₅52.5 kg；N 27.5 kg、P₂O₅105.0 kg和N 192.0 kg、P₂O₅157.5 kg。

Relationship Between Water and Fertilizer for Wheat and Effect on Wheat Yield in Rainfed Field of Loess Plateau

Relationship between water and fertilizer was investigated for three years in isolated microplot experiments. An approximately linear relationship was found between the water content and the wheat yield when the amount of fertilizer was constant. However, the relationship between the amount of fertilizer and the wheat yield was parabolic when the amount of water supply was constant. The amount of nitrogen and water content had a positively alternative effect but the amount of phosphorus had not. Fertilization can improve water effiency and increase wheat yield. The amount of increase in wheat yield by fertilizer can be arranged as follows: with high rainfall year larger than year with medium rainfall larger than year with low rainfall. In different rainfall years(355 mm/a, 411 mm/a, 523 mm/a), when wheat yield is highest, the amount of nitrogen and phosphorus are N 64.5 kg/hm², P₂O₅52.55 kg/hm²; N 127.5 kg/hm², P₂O₅105.0 kg/hm² and N 192.0 kg/hm², P₂O₅157.5 kg/hm² respectively.