摘要：

有机肥部分替代氮肥是实现作物可持续发展的途径之一,探索了小麦有机氮部分替代化肥氮的适宜配比,以及替代后氮素累积、运转以及利用的特征,以期为河北地区冬小麦氮肥减量增效技术提供依据。2021—2023年在河北宁晋进行小麦大田试验,设置9个处理。T1,无氮,单施化肥磷钾肥;T2,高效施肥,单施化学氮磷钾肥;T3~T7,有机肥分别替代T2的20%,40%,60%,80%,100%的氮肥;T8,传统施肥,单施化学氮磷钾肥;T9,有机肥替代T2 100%的氮肥+液态氮肥。2 a试验结果表明,100%替代率+液态氮处理可获得较高的小麦产量;其次是40%替代率处理,其产量与高效施肥处理相当,且试验第2年远高于传统施肥处理。100%替代率+液态氮处理通过起身期补充速效氮,提高了茎叶中氮素含量,植株氮素累积量与高效施肥和传统施肥处理相当;40%,80%替代率处理同样获得与高效施肥处理相当的氮素累积量。20%~100%替代率处理(包括液态氮处理)可以实现较高的茎叶氮素运转率和对籽粒氮的贡献率,其中100%替代率+液态氮处理肥料氮吸收利用效果好,获得了较高的肥料氮累积量、氮肥利用率和氮收获指数,其效果与高效施肥处理相当或略高;其次是40%替代率处理,其效果与高效施肥处理相当或略低。综上,100%替代率+液态氮处理小麦产量、植株氮素累积量、氮素运转率、籽粒氮素累积量及氮效率俱佳,其次是40%替代率处理。

关键词: 小麦, 有机肥, 氮素积累, 氮素运转

Abstract:

Partial substitution of organic fertilizer nitrogen for chemical fertilizer nitrogen is one of the ways to achieve sustainable crop development.This study explored the appropriate ratio of wheat organic nitrogen partial substitution for chemical nitrogen,as well as the characteristics of nitrogen accumulation,transportation,and utilization after substitution,in order to provide a basis for nitrogen fertilizer reduction and efficiency enhancement technology for winter wheat in Hebei Region.Field experiments of the following nine treatments were conducted in Ningjin,Hebei from 2021 to 2023:T1,non-nitrogen,and application of chemical P and K fertilizer alone;T2,high efficiency fertilization treatment,and application of chemical N,P and K fertilizer alone;T3—T7,substitution of 20%,40%,60%,80% and 100% the chemical N rate of T2 with organic fertilizer,respectively;T8,traditional fertilization,and application of chemical N,P and K fertilizer alone;T9,substitution of 100% chemical N rate of T2 with organic fertilizer,and spraying liquid nitrogen fertilizer at the erecting stage.The results of two years of experiments showed that the 100% substitution rate+liquid nitrogen treatment could achieve the highest wheat yield.Secondly,the yield of the 40% substitution rate treatment was equivalent to that of the high efficiency fertilization treatment,and it was much higher than that of the traditional fertilization treatment in the second year of the experiment.The 100% substitution rate+liquid nitrogen treatment increased the nitrogen content in stems and leaves by spraying available nitrogen during the erecting period,and the nitrogen accumulation in plants was equivalent to that of high efficiency fertilization and traditional fertilization treatments.Treatment with 40% and 80% substitution rates also achieved nitrogen accumulation equivalent to the highly efficient fertilization treatment.The 20%—100% substitution rate treatment (including liquid nitrogen treatment) could achieve a higher nitrogen transfer rate in stems and leaves,as well as the contribution rate of nitrogen transfer to grain.Among them,the 100% substitution rate+liquid nitrogen treatment had good fertilizer nitrogen absorption and utilization effect,achieving higher fertilizer nitrogen accumulation,nitrogen utilization rate,and nitrogen harvest index.Nitrogen fertilizer effect of the 100% substitution rate+liquid nitrogen treatment was equivalent to or slightly higher than that of highly efficient fertilization treatment.Secondly,the treatment with the 40% substitution rate had a similar or slightly lower nitrogen fertilizer effect than the highly efficient fertilization treatment.In summary,the 100% substitution rate+liquid nitrogen treatment showed better wheat yield,plant nitrogen accumulation,nitrogen transport rate,grain nitrogen accumulation,and nitrogen efficiency,followed by the 40% substitution rate treatment.

Key words: Wheat, Organic fertilizer, Nitrogen accumulation, Nitrogen transport