我国斯里兰卡木薯花叶病毒的分子特征及致病性分析  

Molecular Characterization and Pathogenicity of the SLCMV Chinese Isolates

作　　者：王国芬[1] 李超萍[1] 时涛[1] 吴会杰[2] 蔡吉苗[1] 李博勋[1] 陆翠梅 黄贵修[1] WANG Guofen;LI Chaoping;SHI Tao;WU Huijie;CAI Jimiao;LI Boxun;LU Cuimei;HUANG Guixiu(Environment and Plant Protection Institute,Chinese Academy of Tropical Agricultural Sciences/Laboratory of Integrated Pest Management on Tropical Grops,Ministry of Agriculture and Rural Affairs/Hainan Key Laboratory for Monitoring and Control of Tropical Agricultural Pests,Haikou,Hainan 571101,China;Zhengzhou Fruit Research Institute,Chinese Academy of Agriculutral Sciences,Zhengzhou,Henan 450009,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/海南省热带农业有害生物监测与控制重点实验室,海南海口571101 [2]中国农业科学院郑州果树研究所,河南郑州450009

出　　处：《热带作物学报》2024年第1期187-196,共10页Chinese Journal of Tropical Crops

基　　金：海南省自然科学基金高层次人才项目(No.2019RC285);国家重点研发计划项目(No.2020YFD1000600);国家木薯产业技术体系项目(No.CARS-11)。

摘　　要：为进一步探究我国斯里兰卡木薯花叶病毒(Sri Lankan cassava mosaic virus,SLCMV)的分子特征及致病性。以感染SLCMV的木薯叶片基因组DNA为模板,PCR扩增获得DNA-A和DNA-B基因组全长,通过生物信息软件分析比较其核酸及氨基酸序列特征;构建了强、弱致病力分离物(SLCMV-Colombo和SLCMV-DG1922)的侵染性克隆,分别将2种致病力分离物的DNA-A和DNA-B组分进行重组,接种烟草(Nicotianatabacum),比较2种分离物的致病性差异。结果显示:我国SLCMV为“旧世界”双组份菜豆花叶病毒,编码包括AV2基因在内的8个开放阅读框(ORFs);具有双生病毒典型的共同序列(CR)、重复序列、TATABox和TAATATT↓AC茎环结构,Rep蛋白羧基末端有7个氨基酸缺失;我国SLCMV的基因组、编码和非编码区与柬埔寨、泰国和越南分离物的相似性在97.0%~100.0%之间,与印度和斯里兰卡早期的分离物相似性为86.5%~98.6%,DNA-B组份与印度木薯花叶病毒株系(ICMV)编码区序列相似性为95.0%~97.6%,与其他9个非洲木薯花叶病毒株系序列之间的序列相似性均低于80.0%。侵染性克隆接种结果证实,强致病力分离物SLCMV-Col的DNA-A(Col-A)组份在烟草叶片表现典型花叶症状中起主要作用,而我国分离物的DNA-B(DG1922-B)能协同Col-A对烟草产生强致病性。本研究分析了我国SLCMV的全基因组结构,建立的侵染性克隆及其技术为进一步解析SLCMV致病性机理提供重要的研究基础。To further explore the molecular characteristics and pathogenicity of Sri Lankan cassava mosaic virus(SLCMV)isolates in China.Mosaic cassava leaves were detected,and the domestic SLCMV isolates full-length ge-nomes of DNA-A and DNA-B were obtained by PCR amplification.It`s nucleic acid and amino acid sequence charac-teristics were analyzed by bioinformatics software.The infectious clones of strong and weak pathogenic isolates(SLCMV-Colombo and SLCMV-DG1922)were constructed.The DNA-A and DNA-B components of the two virulence isolates were recombined,and the pathogenicity differences of the two isolates were compared by tobacco(Nicotiana tabacum)inoculation.The results showed that SLCMV isolates belong to“Old World begomoviruses”encoding 8 open reading frames(ORFs)including the AV2 gene.It has a typical common region(CR),repeat sequence,TATA Box and TAATATT↓AC stem-loop structure of Geminiviruses,and 7-amino-acid are missing at the carboxyl terminal of Rep protein.Domestic SLCMV genome,coding and non-coding region sequences were 97.0%-100.0%similar to the isolates from Cambodia,Thailand and Vietnam,and 86.5%-98.6%similar to the early isolates from India and Sri Lanka.Coding region of DNA-B were 95.0%-97.6%similar to Indian cassava mosaic virus strain(ICMV),were less than 80.0%to the other 9 African cassava mosaic virus strains.Infection clone inoculation showed that the DNA-A(ColA)component of the strong virulent isolate SLCMV-Col played an important role in the typical mosaic symptoms of N.tabacum leaves,while the DNA-B(DG1922-B)of the domestic isolate could cooperate with Col-A to produce strong pathogenicity to tobacco plants.This study analyzed the whole genome structure of SLCMV in China,the infectious clone and its tech-nology provide an important research basis for further pathogenesis research of SLCMV.

关 键 词：斯里兰卡木薯花叶病毒 分子特征 侵染性克隆 致病性 

分 类 号：S435.33[农业科学—农业昆虫与害虫防治]