钝叶草叶斑病病原鉴定  

Identification of the Pathogen of Stenotaphrum helferi Leaf Spot

作　　者：郑金龙[1] 刘文波[2] 贺春萍[1] 易克贤[1] 习金根[1] 粱艳琼 Gbokie Jr Thomas 吴杨[4] ZHENG Jinlong;LIU Wenbo;HE Chunping;YI Kexian;XI Jingen;LIANG Yanqiong;Gbokie Jr Thomas;WU Yang(Environment and Plant Protection Institute,Chinese Academy of Tropical Agricultural Sciences/Key Laboratory of Integrated Pest Management on Tropical Crops,Ministry of Agriculture and Rural Affairs,Haikou,Hainan 571101,China;College of Plant Protection,Hainan University,Haikou,Hainan 570228,China;College of Plant Protection,Nanjing Agricultural University,Nanjing,Jiangsu 210095,China;School of Life Sciences,Jinggangshan University,Ji’an,Jiangxi 343009,China)

机构地区：[1]中国热带农业科学院环境与植物保护研究所/农业农村部热带作物有害生物综合治理重点实验室,海南海口571101 [2]海南大学植物保护学院,海南海口570228 [3]南京农业大学植物保护学院,江苏南京210095 [4]井冈山大学生命科学学院,江西吉安343009

出　　处：《热带作物学报》2021年第4期1086-1091,共6页Chinese Journal of Tropical Crops

基　　金：国家重点研发计划项目(No.2018YFD0201100);国家自然科学基金项目(No.31560564)。

摘　　要：为鉴定钝叶草叶斑病的病原,通过对61份来自中国海南、广东、广西、云南、福建、江苏,以及美国和南非的疑似钝叶草叶斑病的叶片样品进行分离培养,获得120个菌株,对其进行纯化培养、形态学观察、致病性测定,利用来自海南的钝叶草为靶标寄主,并利用rDNA-ITS、GAPDH、TUB2引物对55号菌株进行分析鉴定。结果表明,经柯赫氏法则验证40株菌株不致病,70株致病性较弱,10株致病性强;选择55号致病性强菌株,进行形态观察,初步确定该病的病原菌为新月弯孢霉(Culvularia lunata),经3种引物的PCR扩增测序鉴定,和C.lunata相似性达到99%,进一步确定钝叶草叶斑病的致病菌为新月弯孢霉。研究结果将为今后对钝叶草叶斑病的发病规律、防治方法及抗病机制等方面的研究提供理论依据。This study aimed to identify the pathogen of the leaf spot of Stenotaphrum helferi.A total of 61 leaf samples of S.helferi with suspected leaf spot disease were collected from six provinces in China(Hainan,Guangdong,Guangxi,Yunnan,Fujian and Jiangsu),the United States and the South Africa.The potential causal agents were isolated and 120 bacterial strains were obtained.The strains were identified in morphology,and by conducting pathogenicity assay in the accesions from Hainan.In addition,the strains were identified by the PCR method based on the rDNA internal transcribed spacer region(rDNA-ITS),glyceraldehyde-3-phosphate dehydrogenase(GAPDH)andβ-tubulin(TUB2)sequences.The analysis followed Koch’s law and showed 40 strains with no pathogenisis,70 strains with weak pathogenisis,and 10 strains with strong pathogenisis.The strains of No.55 with strong pathogenisis were selected for morphological observation,and the pathogens of the disease were preliminarily determined.Sequence identities of rDNA-ITS,GAPDH and TUB2 between No.55 strains and Curvularia lunata reached 99%,suggesting that the pathogenic bacteria of the leaf spot in S.helferi was C.lunata.Our findings would provide data to support future studies on the epidemiology,resistance mechanism and control strategy of the leaf spot disease of bluestocked grass.

关 键 词：钝叶草 叶斑病 新月弯孢菌 病原菌鉴定 致病性测定 

分 类 号：S436.8[农业科学—农业昆虫与害虫防治]