氮磷配施对旱地小麦产量和吸肥特性的影响

Effects of fertilizer N,P on wheat yield and nutrients uptake characters in dryland of Loess Plateau

以已进行18年的小麦连作肥料定位试验为基础,研究了长期施用氮肥和磷肥对小麦的增产效应及对小麦吸收氮磷养分的影响。结果表明:(1)单施氮肥90 kg/hm2和180 kg/hm2时,小麦的增产率分别为198.42%和122.14%,小麦籽粒的氮含量分别比不施肥增加33.3%和35.9%;单施磷肥无明显的增产作用;氮磷配施对小麦有明显的增产作用,不同氮磷配施处理的增产率为267.84%-472.88%。(2)秸秆氮含量与氮肥施用量间的正相关关系显著,与磷肥施用量的相关性不显著,而秸秆磷含量与氮肥和磷肥施用量相关性均不显著;籽粒氮含量、磷含量与氮肥、磷肥施肥量的相关性均不显著。(3)当氮肥施用量小于125.25 kg/hm2时,氮收获指数随氮肥施用量的增加而增加,适量施磷氮收获指数增加,当磷肥施用量为26.30 kg/hm2时,氮收获指数达61.22%,之后随磷肥施用量增加,氮收获指数基本保持不变;氮肥和磷肥的施用量分别为131.76和63.59 kg/hm2时,最大磷收获指数为64.75%。

Based on a long-term experiment of applying N and P fertilizer for 18 years ,effects of longterm fertilization on wheat yield and N and P uptake were studied. Result showed that, fertilizer N increased wheat yield clearly,the yield increased by 198.42% and 122.14% with 90 kg/hm^2 and 180 kg/hm^2 respectively,but the yield showed no significant increase with P fertilizer applied only. N and P applied together could increase the yield from 267.84% to 472.88%. Under the conditions,N content of wheat stem was of significant relationship with N applied amount, and no prominence relationship with P applied amount;P conent of wheat stem and N or P content of wheat seed were not significant affected by fertilizer N or P applied. The N Harvest Index increased with N applied amount growing until 125.25 kg/hm^2,when P applied was 26.30 kg/hm^2 amount,it could reach 61.22% P Harvest Index could reach 64.75% when P and N applied amount were 131.76 kg/hm^2 and 63.59 kg/hm^2 respectively.