施氮对不同结瘤特性花生土壤固氮菌多样性和群落组成的影响  

Responses of soil diazotrophic diversity and community composition of nodulating and non-nodulating peanuts(Arachis hypogaea L.)to nitrogen fertilization

作　　者：孙棋棋 郑永美[1] 于天一[1] 吴月 杨吉顺[1] 吴正锋[1] 吴菊香[1] 李尚霞[1] SUN Qi-Qi;ZHENG Yong-Mei;YU Tian-Yi;WU Yue;YANG Ji-Shun;WU Zheng-Feng;WU Ju-Xiang;LI Shang-Xia(Shandong Peanut Research Institute,Qingdao 266100,Shandong,China)

机构地区：[1]山东省花生研究所,山东青岛266100

出　　处：《作物学报》2022年第10期2575-2587,共13页Acta Agronomica Sinica

基　　金：国家重点研发计划项目(2018YFD1000906);财政部和农业农村部国家现代农业产业技术体系建设专项(CARS-13);山东省自然科学基金项目(ZR202103030197)资助。

摘　　要：施氮对豆科作物土壤固氮菌的影响机理尚不明确。深入研究施氮对花生土壤固氮菌的影响,对花生田高效施氮和农业可持续发展具有重要意义。本研究以结瘤(花育22)和不结瘤(BL)花生为材料,设置N0(不施氮,0 kg hm^(-2))、N60(减量施氮,60 kg hm^(-2))、N120(常量施氮,120 kg hm^(-2))和N180(过量施氮,180 kg hm^(-2))4个施氮水平,探讨不同施氮水平对不同结瘤特性花生土壤固氮菌的影响。采用实时荧光定量PCR和高通量测序技术,以nifH基因为标靶,分析土壤固氮菌丰度、多样性和群落组成。结果表明:(1)施氮显著提高土壤氮组分含量,N120结瘤花生土壤中微生物量氮和可溶性有机氮显著高于不结瘤花生。不结瘤花生荚果产量随施氮水平呈线性增加,而结瘤花生产量不受施氮影响。(2)施氮条件下,不结瘤花生土壤nifH拷贝数显著降低,而结瘤花生土壤nifH拷贝数随施氮水平增加先降低后增加。(3)施氮对不结瘤花生土壤固氮菌多样性先抑制后促进,而施氮对结瘤花生土壤固氮菌多样性呈先促进后抑制的模式,并在N120达到最大值。(4)施氮显著改变不结瘤花生土壤固氮菌群落组成,不同施氮水平优势属分别为nonrank_Bacteria(N0)、unclassified_Cyanobacteria(N60)、nonrank_Bacteria(N120)和Skermanella(N180),硝态氮是影响处理间土壤固氮菌群落组成差异的唯一显著因素;结瘤花生土壤各施氮水平固氮菌群落组成相似,除N120外,均以unclassified_Proteobacteria和Skermanella占优。不结瘤与结瘤花生土壤固氮菌对施氮水平截然不同的响应可能是由于二者分别受到不同氮源的影响(肥料氮vs.根瘤固氮)。本研究中120 kg hm^(-2)是对土壤固氮和花生生产最优的施氮水平。Influencing mechanism of nitrogen(N)fertilization on soil diazotrophs of legumes remains unclear.Further study on the effect of different nitrogen application rates on soil nitrogen-fixing is of critical importance for high-efficiency nitrogen application of peanut field and agricultural sustainability development.We used the non-nodulating(BL)and nodulating(Huayu 22,HY22)peanuts as experimental materials,with four N application rates arranged,including N0(without N application,0 kg hm^(-2)),N60(N reduced-application,60 kg hm^(-2)),N120(N common-fertilization,120 kg hm^(-2)),and N180(N over-application,180 kg hm^(-2)).The qRT-PCR and Illumina high-throughput sequencing of nifH gene were used to analyze soil diazotrophic abundance,diversity,and community composition.Results showed that:(1)N fertilization significantly increased the contents of soil N fraction.Especially at N120,the soil microbial biomass carbon and dissolved organic carbon of nodulating peanut were significantly higher than that of non-nodulating peanut.The podding yields of non-nodulating peanut increased positively and linearly with the increasing N rates,while those of nodulating peanut was unaffected by N fertilization.(2)Under N fertilization,soil nifH copies of non-nodulating peanut were inhibited,while that of nodulating peanut decreased firstly and then increased with N rates increased.(3)N fertilization reduced firstly and then enhanced the soil diazotrophic diversity from non-nodulating peanut with N rates,while N fertilization increased firstly and then decreased that from nodulating peanut,with peak value at N120.(4)Nonrank_Bacteria and Proteobacteria were the predominated phyla.N fertilization altered the soil diazotrophic community composition of non-nodulating peanut,with dominant genera being nonrank_Bacteria(N0),unclassified_Cyanoabcteria(N60),nonrank_Bacteria(N120),and Skermanella(N180),respectively,and NO3-N being the overriding determinative factor,while exerted no effect on that of nodulating peanut(being dominated by unclassi

关 键 词：花生 结瘤特性 固氮菌 施氮 根瘤固氮 

分 类 号：S565.2[农业科学—作物学] S154.3