摘要

为明确引起广西大化菜心表现花叶斑驳症状的病毒病原，从广西大化采集4个表现典型症状的菜心样品，采用反转录聚合酶链式反应（reverse transcriptionpolymerase chain reaction，RTPCR）、DNA分段克隆、cDNA末端快速扩增技术（rapid amplification of cDNA ends，RACE）和遗传进化树构建等方法对样品进行了检测鉴定、全基因组序列克隆和遗传进化分析。结果显示，利用马铃薯Y病毒属通用简并引物从4个菜心样品中均能扩增出目的片段，将所得PCR产物克隆并测序，所得序列与NCBI中报道的芜菁花叶病毒（turnip mosaic virus，TuMV）分离物具有较高的核苷酸相似性，结果初步证实所采集的菜心样品感染了TuMV;利用7对特异引物和5′/3′RACE引物对TuMV广西菜心分离物的全基因序列进行分段克隆、测序，最终获得一条大小为9 834 nt的全长基因组序列。BLAST分析发现，该序列与TuMV其他分离物的基因组序列一致性为77.84%～96.06%，其中与中国云南安宁分离物TuMV_CHN229（登录号：LC537500.1）的一致性最高（96.06%），依据上述结果将该分离物命名为TuMV_GXdh1（GenBank登录号：PP079014）。遗传进化分析结果显示，TuMV_GXdh1与中国北京、山东、广东、台湾等分离物以及美国、日本等14 个分离物聚集在一个大分支上，分属于worldB组，其中与中国云南安宁分离物和浙江杭州分离物（TuMV_CHZH33A，GenBank登录号：LC537526.1）聚集在一个小分支，亲缘关系最近。综上，本研究首次获得TuMV广西分离物的全基因序列，并对其遗传进化等进行了分析。

关键词

广西; 菜心; 芜菁花叶病毒; 全基因组序列; worldB组

中图分类号：

S 432.1

文献标识码： A

DOI： 10.16688/j.zwbh.2024472

Complete genome sequence analysis of turnip mosaic virus isolate from Brassica rapa var. chinensis in Dahua， Guangxi，China

MO Cuiping1， CHEN Jinqing1， LI Youcong1，2， XIE Huiting1， QIN Bixia1， CUI Lixian1，LI Feifei4， TANG Yafei3， CAI Jianhe1*， LI Zhanbiao1*

（1. Plant Protection Research Institute， Guangxi Academy of Agricultural Sciences， Key Laboratory of Green

Prevention and Control on Fruits and Vegetables in South China， Ministry of Agriculture and Rural Affairs， Key

Laboratory of Biology for Crop Diseases and Insect Pests of Guangxi， Nanning 530007， China; 2. College of

Agriculture，Guangxi University， Nanning 530004， China; 3. Institute of Plant Protection， Guangdong Academy

of Agricultural Sciences， Guangdong Provincial Key Laboratory of High Technology for Plant Protection，

Guangzhou 510640， China; 4. Guangxi Vocational University of Agriculture， Nanning 530007， China）

Abstract

To determine the viral pathogen responsible for mosaic and mottling symptoms observed on Brassica rapa var. chinensis in Dahua， Guangxi， China， four samples with typical symptoms were collected for molecular analysis. Reverse transcriptionpolymerase chain reaction （RTPCR）， DNA fragment cloning， rapid amplification of cDNA ends （RACE） and phylogenetic analysis were performed. Using universal degenerate primers targeting Potyvirus species， PCR amplification yielded expected products from all four samples. Subsequent cloning and sequencing revealed high nucleotide identity with turnip mosaic virus （TuMV）， confirming infection by TuMV. Fulllength genome sequencing of a representative isolate was achieved using seven specific primer pairs along with 5′ and 3′ RACE primers. The complete genome was 9 834 nucleotides in length. BLAST analysis showed that the sequence shared 77.8%-96.06% nucleotide identity with other TuMV isolates in GenBank， with the highest similarity （96.06%） to isolate TuMV_CHN229 from Anning， Yunnan （GenBank accession： LC537500.1）. This isolate was designated TuMV_GXdh1 （GenBank accession： PP079014）. Phylogenetic analysis based on the complete genome showed that TuMV_GXdh1 clustered within the worldB group， forming a subgroup with the Yunnan TuMV_CHN229 and Zhejiang TuMV_CHZH33A isolates （GenBank accession： LC537526.1）， indicating a close evolutionary relationship. This study represents the first report of a full genome sequence of TuMV from Guangxi， providing new insights into its molecular characteristics and phylogenetic placement.

Key words

Guangxi; Brassica rapa var. chinensis; turnip mosaic virus; complete genome; worldB group

芜菁花叶病毒（turnip mosaic virus，TuMV）是隶属于马铃薯 Y 病毒科Potyviridae马铃薯Y病毒属Potyvirus的一种正单链RNA病毒，基因组全长约10 kb。包含 2个开放阅读框（open reading frame，ORF），大的……