侵染湖南甘薯种质资源的曲叶病毒和杆状病毒的检测及其亲缘关系分析

采用PCR技术对2015—2016年从湖南省多个市县采集的180份甘薯种质资源进行两种DNA病毒（sweet potato leaf curl virus,SPLCV和sweet potato badnavirus,SPBV）检测,并以PCR扩增产物序列为基础,对这两种病毒的亲缘关系进行分析。结果表明：（1）180份甘薯种质资源中,22份检测出SPLCV,占总数的12.2%;32份检测出SPBV,占总数的17.8%;8份同时检出SPLCV和SPBV这两种病毒,占总数的3.9%。（2）检出SPLCV的市县有长沙、永州、怀化、邵阳、郴州、常德、娄底、益阳、岳阳和株洲;检出SPBV的市县有长沙、永州、怀化、衡阳和邵阳;检出两病毒复合侵染的市县有怀化、长沙、永州和邵阳。（3）基于病毒全基因组序列分析显示,全球已报道的36个SPLCV分离物可分为3组,本研究获得的12个湖南分离物可分别归于3个组中,其中6个归于组Ⅰ,1个归于组Ⅱ,5个归于组Ⅲ,表明湖南SPLCV具有高度多样性。（4）基于病毒运动蛋白和外壳蛋白编码基因部分序列分析显示,全球已报道的36个SPBV分离物可分为4组,绝大部分分离物属于组Ⅰ,我国1个安徽分离物单独成组（组Ⅱ）,我国2个山东分离物和1个海南分离物构成1个组（组Ⅲ）,本研究获得的2个湖南分离物其中1个归于组Ⅰ,而另1个与已报道各分离物的核苷酸序列均存在显著差异,相似性仅为74.92%,单独成组（组Ⅳ）,表明我国SPBV具有高度的变异性,存在多个变异类型。本研究结果可为湖南地区这两种病毒病防控提供依据。

Detection and Genetic Relationship Analysis of Sweet Potato Leaf Curl Virus and Sweet Potato Badnavirus Infecting Sweet Potato Germplasm Resources in Hunan,China

180 sweet potato germplasm resources from different regions of Hunan were used to detect sweet potato leaf curl virus (SPLCV) and sweet potato badnavirus (SPBV) during 2015-2016. The genetic relationship of the two viruses was analyzed based on the sequence of PCR amplification products. 22 sweet potato germplasm resources were infected with SPLCV, making up 12.2% of the total, and 32 sweet potato germplasm resources were infected with SPBV, or 17.8% of the total. There were 8 sweet potato germplasm resources infected with both SPLCV and SPPV, accounting for 3.9% of all 180 sweet potato germplasm resources. SPLCV was detected in Changsha, Yongzhou, Huaihua, Shaoyang, Chenzhou, Changde, Loudi, Yiyang, Yueyang and Zhuzhou. SPBV was detected in Changsha, Yongzhou, Huaihua, Hengyang and Shaoyang. Both SPLCV and SPBV were detected in Huaihua, Changsha, Yongzhou and Shaoyang. Based on the whole genome sequence analysis of the virus, 36 SPLCV isolates reported in the world were divided into 3 groups. The 12 strains isolated from Hunan obtained in this study could be classified into 3 groups, six of them belonged to groupⅠ and one of them to groupⅡ, five of them to groupsⅢ, meaning that sweet potato leaf curl virus was highly diverse in Hunan. Based on the partial sequence analysis of viral movement protein and coat protein coding genes, 36 SPBV isolates reported in the world could be divided into 4 groups, the most of isolates belong to group I, and one Anhui isolate in China was divided into groupⅡalone. Two Shandong isolates and one Henan isolate in China constituted groupⅢ. One of the two Hunan isolates obtained in this study belongs to groupⅠ, and the other was significantly different from the reported isolates, only 74.92% similarity, classified groupⅣ. The results indicate that SPBV have high variability and many types of variation in China. This study could offer a useful reference for prevention and control of these two kinds of sweet potato virus diseases in China.