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番茄黄化曲叶病(tomato yellow leaf curl disease,TYLCD)在我国危害日益严重.为了对该病进行深入有效的了解,根据已知的番茄黄化曲叶病毒(tomato yellow leaf curl virus,TYLCV)基因组DNA-A序列的保守区段,设计两对背向引物;针对北京地区的3个TYLCV分离物进行分子鉴定.结果显示该分离物为单组分病毒,不含DNA-B和卫星DNA-β,是TYLCV的2个新分离物.TYLCV-BJ1与BJ2基因组全长分别为2781bp和2779bp,同源性为99.8%,都编码6个开放阅读框.对TYLCV的分子进化分析表明,国内现已发现的TYLCV株系亲缘关系都很接近,同源性在97.1~99.9%,属于以色列TYLCV-IL株系进化下的一个近代分支.从全基因组和各基因的逐个比对结果看,TYLCV的AV1和AV2保守性最高,其次是AC2和AC3.当TYLCV-Mld进化成TYLCV-IL时,AC1和AV4基因发生了较大的变化,IR区的同源性更是从小于70%上升到94.3%.国内的TYLCV株系分成2个亚群,但在地理分布上没有形成严格的区域限定,北京分离物属于CN I亚群.
Tomato yellow leaf curl disease (TYLCD) is more and more harmful in our country.In order to understand the disease in a more efficient way, according to the known tomato yellow leaf curl virus (TYLCV) Two pairs of reverse primers were designed according to the conserved region of genomic DNA-A sequence, and three TYLCV isolates were identified in Beijing area.The results showed that the isolates were single-component viruses without DNA-B and satellite DNA- β, are two new isolates of TYLCV.The total length of TYLCV-BJ1 and BJ2 genomes are 2781bp and 2779bp, respectively, and their homologies are 99.8%, all encoding 6 open reading frames.The molecular phylogenetic analysis of TYLCV shows that the domestic The TYLCV isolates were found to have close genetic relationship with homology of 97.1-99.9%, belonging to a modern branch under the evolution of the TYLCV-IL strain in Israel.According to the genome-wide and gene-by-genome alignment results, TYLCV AV1 and AV2 were the most conserved, followed by AC2 and AC3. When TYLCV-Mld evolved into TYLCV-IL, the AC1 and AV4 genes changed greatly, and the homology of IR region increased from less than 70% to 94.3 The TYLCV strains in China are divided into two subgroups, but they are not formed in geographical distribution Defining a grid area, Beijing CN I isolates belong to subgroup.