Small RNA深度测序鉴定甘薯种质的甘薯曲叶病毒

Identification of Sweet Potato Leaf Curl Virus by Small RNA Deep Sequencing in Sweet Potato Germplasm

本研究利用Small RNA深度测序对长沙、永州、邵阳等地采集的甘薯种质资源病毒症状样品进行鉴定,发现样品中含有与甘薯曲叶病毒同源的系列。设计引物进行PCR扩增,鉴定出24个SPLCV-AC1基因片段序列,经NCBI-Blast比对,与10个不同株系SPLCV同源性达96%以上。为进一步获得SPLCV全长序列,设计背靠背引物,经PCR扩增、鉴定,获得3个SPLCV全长序列。系列进化分析显示,这3个SPLCV分离物聚为同一分支,其中SPLCV(76)序列大小2 774 bp,与甘薯乔治亚曲叶病毒中国分离物、甘薯金脉病毒具有较高同源性;SPLCV(47)序列大小2 777 bp,与甘薯河南曲叶病毒分离物具有较高同源性;SPLCV(68)序列大小2 832 bp,与甘薯广西曲叶病毒分离物具有96%的同源性。以上同源系列与Small RNA测序显示结果相一致。本研究结果为甘薯病毒病防控提供理论依据。

In this study,the virus symptom samples of sweet potato germplasm resources collected from Changsha,Yongzhou and Shaoyang were identified by small RNA deep sequencing,and it was found that the samples contained a series of homology sequences with sweet potato leaf curl virus.24 SPLCV-AC1 gene fragments sequences were identified after amplified by PCR with designed primers,which had over 96%homology with 10 different lines SPLCV by NCBI-Blast comparison.In order to further obtain the full-length sequence of SPLCV,back-to-back primers were designed,and then three full-length sequences of SPLCV were obtained by PCR amplification and identification.A series of evolutionary analysis showed that the three SPLCV isolates were clustered into the same branch.Among them,the sequence size of SPLCV(76)was 2 774 bp,which had high homology with Chinese isolates of sweet potato leaf curl Georgia virus and golden vein virus in sweet potato.The sequence of SPLCV(47)was 2 777 bp,which had high homology with the isolates of sweet potato leaf curl Henan virus.The SPLCV(68)sequence was 2 832 bp,which had 96%homology with the isolates of sweet potato leaf curl Guangxi virus.These homologous sequences were consistent with the results of Small RNA sequencing.The results of this study provide theoretical basis for prevention and control of sweet potato virus disease.