Co-incorporation of Chinese milk vetch(Astragalus sinicus L.)and chemical fertilizers alters microbial functional genes supporting short-time scale positive nitrogen priming effects in paddy soils  

作　　者：Limin WANG Chunmei HE Dongfeng HUANG Juhua YU Cailing LIU Qinghua LI Yibin HUANG Juan LI Fei WANG 

机构地区：[1]Institute of Resources,Environment and Soil Fertilizer,Soil and Fertilizer Institute,Fujian Academy of Agricultural Sciences,Fuzhou 350012(China) [2]School of Resources and Environment Engineering,Anhui University,Hefei 230601(China)

出　　处：《Pedosphere》2024年第3期567-576,共10页土壤圈（英文版）

基　　金：supported by the Youth Talent Program of Fujian Academy of Agricultural Sciences,China(No.YC2019006);the External Cooperation Program of Fujian Academy of Agricultural Sciences,China(No.DWHZ-2022-20);the Foundation of Fujian Academy of Agricultural Sciences,China(No.CXTD2021012-2);the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001);the Special Fund of Fundamental Scientific Research at Nonprofit Research Institutions in Fujian,China(No.2022R1025001);the Natural Science Foundation of Fujian Province,China(No.2020J011358);the Modern Agro-Industry Technology Research System-Green Manure,China(No.CARS-22-G-01);“5511”Collaborative Innovation Engineering,China(No.XTCXGC2021009)。

摘　　要：Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation practices.However,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South China.Here,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate quality.The MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of incubation.Correlation analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit nitrification,thereby increasing the short-term

关 键 词：green manure gross priming effect incorporation practice microbial mechanism net priming effect rice field soil 

分 类 号：S154.3[农业科学—土壤学]