黄土高原长期施用磷肥效应研究

Effect of Long-term P Fertilization on Wheat Yield of Loess Plateau

以黄土高原长期定位试验为基础,研究施一定量氮肥（90 kg/hm2）的前提下,长期施用磷肥对黄土高原旱作冬小麦的肥料效应。结果表明,长期施用磷肥的农田施磷仍能显著提高小麦的产量,增产量达1393.75~2121.00kg/hm2,增产率为48.41%~73.67%,本试验中施磷39.6 kg/hm2时小麦产量达最大值5000 kg/hm2,这与小麦成穗数最大时的施肥量结果一致;产量与施磷量关系用回归方程Y=-0.8667X2＋82.641X＋3008.4（R2=0.92）拟合效果良好;施磷主要是通过影响小麦成穗数来影响小麦产量,而对穗粒数和千粒重的促进作用不明显;施磷还可促进小麦对氮磷钾养分的吸收利用,提高肥料的肥效和利用率;施磷过少不能满足作物需求,小麦产量较低,施磷过多小麦产量不会随施肥量的增加继续提高,反而有一定幅度的下降。

Based on the long-term fertilization experiment of Loess Plateau,the effect of long-term P fertilization on winter wheat yield was sudied under certain amount of N fertilier（90 kg/ha）.The results showed that the yield of wheat with P fertilization is still increased obviously in the field with long-term P fertilization.The wheat yield increased by1 393.75-2 121.00 kg/ha and 48.41%-73.67% higher compared to the control treatment.The wheat yield reached the highest value 5 000 kg/ha in the P treatment of 39.6 kg/ha,which was consist with the value of P fertilization when the spike number was highest.The relationship between yield and the amount of P fertilizer application fit the regression equation Y=-0.866 7X2 ＋82.641X＋3 008.4（R2 =0.92） well,P fertilizer mainly influenced the yield of wheat by changing spike number per ha,however,its′ impact on both of grains per spike and 1 000 grains yield was not obvious.The P fertilization can also promoted the absorption and utilization of N,P,K in wheat,and improved fertilizer efficiency and fertilizer use efficiency.Too little P fertilizer can not meet the demand of crops and the wheat yield was low,the wheat yield will not contiue to raise with the increasing of amount of P fertilizer when excessive amount of P fertilizer was used,on the contrary,certain decrese happened.