秸秆还田下氮肥调控对寒地水稻产量及氮素积累转运的影响OA

[Objective]In order to alleviate the problem of soil nitrogen competitive consumption and yield reduction caused by straw decomposition in the early stage of rice straw returning in cold region,this study used Kenjing 8 as the experimental material from 2022 to 2023,and designed four nitrogen fer-tilizer increase regulation strategies(N1 conventional nitrogen application,N2 tillering fertilizer increase N15%,N3 regulating fertilizer increase N15%,N4 panicle fertilizer increase N15%)under the condi-tions of straw leaving and returning through pot experiment.[Method]By measuring rice yield and its components,soil nutrients and plant nitrogen content,the effects of increasing nitrogen fertilizer on rice yield and nitrogen accumulation and transport under straw returning were analyzed.[Result]Study on the effects of rice yield and nitrogen accumulation and transport in cold region.The results showed that under the condition of straw leaving or returning to the field,the rice yield was N3>N4>N2>N1 under the four nitrogen fertilizer application methods,and N3 increased the yield by increasing the number of panicles,seed setting rate and 1 000-grain weight.Compared with N1 treatment,the yield of N3 treat-ment was significantly increased by 7.13%,and the contents of soil available nitrogen and available po-tassium were increased by 38.51%and 13.15%,respectively.Under the condition of straw returning,N3 treatment significantly improved the nitrogen use efficiency of plants,and the nitrogen accumulation of stem sheath and panicle at maturity stage increased by 16.15%-26.52%and 19.75%-22.86%respec-tively compared with N1 treatment.The nitrogen production efficiency of dry matter and nitrogen produc-tion efficiency of rice were better than those of conventional fertilization.[Conclusion]In summary,the nitrogen application mode of 15%nitrogen increase by regulating fertilizer under straw returning can ef-fectively coordinate the contradiction between straw decomposition and nitrogen co-demand,increase the nitrogen accumulation of stem and sheath and spike at maturity stage,and increase rice yield,which provides theoretical basis and technical support for improving soil fertility and crop productivity.