有机肥部分替代氮肥对优质麦生长、品质和氮效率的影响

Effects of Partial Substitution of Chemical Fertilizer by Organic Fertilizer on Growth,Quality and Nitrogen Efficiency of Quality Wheat

旨在探索华北地区有机肥替代氮肥的比例,以及替代后产量稳定的生理基础和替代后增喷液态氮肥的效果,以期为该区冬小麦氮肥减量高产高效技术提供依据。2020—2022年在河北宁晋进行小麦田间试验,设置8个处理。T1,不施氮,单施化学磷钾肥;T2,单施化学氮磷钾肥(对照);T3—T7,有机肥分别替代T2处理20%,40%,60%,80%,100%的氮肥;T8,有机肥替代T2处理100%的氮肥+起身期喷施液态氮肥。结果表明,有机肥替代率29.5%~66.7%和100%替代率+液态氮处理小麦产量较高,与对照相当,该施肥条件下多数时期叶面积指数和叶片SPAD值也较高,这是有机肥替代化肥后产量稳定的生理基础。有机肥替代率大于40%小麦品质较高,尤其40%替代率处理的稳定时间、拉伸面积和最大拉伸阻力较对照分别提高了17.8%,23.5%,9.1%。对照、40%和100%替代率+液态氮肥处理氮效率指标大多表现较优,籽粒吸氮量、氮肥效率和氮素吸收效率较高。有机肥替代氮肥能明显增加起身—灌浆期0~80 cm和成熟期0~60 cm土壤硝态氮含量,使土壤硝态氮出现表聚现象,替代率越高该层次土壤硝态氮含量越高;有机肥替代氮肥能明显降低成熟期80~100 cm土壤硝态氮含量,从而降低雨季氮素淋溶风险。综上,40%替代率和100%替代率+液态氮肥处理小麦产量、品质、氮效率俱佳,效益显著。

Partial substitution of chemical fertilizer with organic fertilizer is being increasingly recognized as a promising approach for achieving sustainable agriculture.This paper explores the proportion of organic fertilizer substitution nitrogen fertilizer,physiological basis for stable yield after substitution nitrogen fertilizer,and the effect of spraying liquid nitrogen after substitution nitrogen fertilizer in North China,in order to provide a basis for the technology of reducing nitrogen fertilizer and increasing yield and efficiency of winter wheat in this region.Field experiments of the following eight treatments were conducted in Ningjin,Hebei from 2020 to 2022:T1,non-nitrogen,application of chemical P and K fertilizer alone;T2,application of chemical N,P and K fertilizer alone;and T3-T7,substitution of 20%,40%,60%,80%and 100%the chemical N rate of T2 with organic fertilizer,respectively;T8,substitution of 100%chemical N rate of T2 with organic fertilizer,and spraying liquid nitrogen fertilizer at the erecting stage.The results showed that the organic fertilizer substitution rate of 29.5%-66.7%and the 100%substitution rate+liquid nitrogen treatment had higher wheat yield,and their yield was comparable to the CK.Under this fertilization condition,the leaf area index and leaf SPAD value were also higher at most stages,which was the physiological basis for stable yield after replacing chemical fertilizer with organic fertilizer.When the organic fertilizer substitution rate was greater than 40%,the wheat grain quality was higher,especially when the organic fertilizer substitution rate was 40%,the stability time,tensile area,and maximum tensile resistance were increased by 17.8%,23.5%,and 9.1%,respectively,compared to the CK.The nitrogen efficiency indicators of the CK,40%substitution rate,and 100%substitution rate+liquid nitrogen fertilizer treatments mostly performed better,with higher nitrogen uptake of grain,nitrogen fertilizer efficiency and nitrogen uptake efficiency.Substitution of chemical fertilizer with organic fertilizer significantly increased the nitrate nitrogen content in soil 0-80 cm from the erecting to the filling stage and 0-60 cm at the mature stage,resulting in a phenomenon of surface accumulation of soil nitrate nitrogen.The higher the replacement rate of organic fertilizer,the higher the nitrate nitrogen content in this layer of soil.Replacing nitrogen fertilizer with organic fertilizer could significantly reduce the nitrate nitrogen content of 80-100 cm soil in the mature stage,thereby reducing the risk of nitrogen leaching in the rainy season.Based on the above conclusions,the treatment of 40%substitution rate and 100%substitution rate+liquid nitrogen fertilizer had excellent wheat yield,quality,and nitrogen efficiency,with significant benefits.