设施连作枯萎病黄瓜根际亚硝酸盐氧化细菌群落特征  

Community characteristics of nitrite-oxidizing bacteria in the rhizosphere of Fusarium wilt-diseased cucumber caused by continuous greenhouse cultivation

作　　者：郑晨萌 刘星[1] 张影[1] 任秀娟[1] 陈碧华 王菲[1] 申长卫 吴大付[1] ZHENG Chenmeng;LIU Xing;ZHANG Ying;REN Xiujuan;CHEN Bihua;WANG Fei;SHEN Changwei;WU Dafu(College of Resources and Environmental Sciences,Henan Institute of Science and Technology/Henan Engineering Research Center of Biological Pesticide&Fertilizer Development and Synergistic Application,Xinxiang 453003,China;School of Horticulture Landscape Architecture,Henan Institute of Science and Technology,Xinxiang 453003,China)

机构地区：[1]河南科技学院资源与环境学院/河南省生物药肥研发与协同应用工程研究中心,新乡453003 [2]河南科技学院园艺园林学院,新乡453003

出　　处：《中国生态农业学报（中英文）》2022年第11期1807-1818,共12页Chinese Journal of Eco-Agriculture

基　　金：国家自然科学基金项目(41601250);河南省科技攻关计划项目(222102110016)资助。

摘　　要：集约化设施黄瓜连作导致枯萎病高发,但根际功能微生物在其中扮演的角色尚不十分清楚。本研究以设施连作黄瓜为供试对象,通过采集枯萎病植株和健康植株根际土壤样品,采用实时荧光定量PCR和高通量扩增子测序技术,分析病株和健株根际间两种亚硝酸盐氧化微生物——硝化杆菌(Nitrobacter)和硝化螺菌(Nitrospira)丰度和群落多样性及结构差异。结果表明:病株根际亚硝态氮含量和Nitrospira丰度与健株无差异,但亚硝酸盐氧化潜势和Nitrobacter丰度更高(P<0.05)。Nitrobacter和Nitrospira群落多样性在病株和健株根际间均无显著差异,但群落结构显著不同。具体来看,病株根际Nitrobacter Cluster 6、Nitrobacter Cluster 5和Namibia soil Cluster 1平均相对丰度显著高于健株(P<0.05),但Nitrobacter Cluster 2b和Nitrospira lineageⅡ平均相对丰度低于健株。亚硝酸盐氧化潜势与Nitrobacter丰度和Nitrobacter Cluster 6平均相对丰度均显著正相关(P<0.05)。冗余分析表明,亚硝态氮含量是影响Nitrobacter和Nitrospira群落结构最重要的土壤理化因子。本研究表明,设施连作黄瓜枯萎病的发生导致了植株根际亚硝酸盐氧化细菌群落结构变化,功能微生物群落及其活性的恢复应是设施连作病害土壤改良的重要方面。Greenhouse cultivation is the most common method of vegetable production worldwide,and cucumber is one of the most important greenhouse vegetables.However,continuous cucumber cropping in intensive greenhouse production causes a high incidence of Fusarium wilt.It has been demonstrated that the occurrence of this disease was correlated with the alteration in plant rhizosphere microbiome.However,previous studies have focused on the overall microbial community(i.e.,bacteria and fungi).The potential role of functional rhizosphere microorganisms in disease occurrence remains largely unclear.Nitrite oxidation(NO_(2)^(−) conversion to NO_(3)^(−)),performed by nitrite-oxidizing bacteria(NOB),is a vital process in soil nitrification and therefore affects soil N availability and plant nitrogen uptake.In this study,we targeted greenhouse cucumbers subjected to continuous cropping by using rhizosphere soil samples from healthy plants(HPR)and Fusarium wilt-diseased plants(DPR),and assessed differences in their abundances and community diversities and structures of two major groups of NOB,Nitrobacter and Nitrospira,using real-time quantitative PCR and high-throughput amplicon sequencing.The results showed that there was no significant difference in the NO_(2)^(−)-N content between DPR and HPR,whereas the potential nitrite oxidation rate(PNOR)in DPR was approximately twice as high as that of HPR(P<0.05).Nitrobacter abundance in the DPR was significantly higher than in the HPR(P<0.05),with no significant difference in Nitrospira abundance.Nitrobacter abundance was significantly and positively correlated with PNOR,suggesting that it dominated soil nitrite oxidation.For both Nitrobacter and Nitrospira,community diversity did not differ between the DPR and HPR,whereas significant differences in community structures were observed(P<0.05).Phylogenetic analyses revealed that the main members of the Nitrobacter community were Nitrobacter Cluster 3,Cluster 3-like,Cluster 2b,Cluster 4,Cluster 6,Cluster 1,and Cluster 5;in the Nitrosp

关 键 词：连作 设施黄瓜 枯萎病 亚硝酸盐氧化细菌 

分 类 号：S154[农业科学—土壤学]