›› 2017, Vol. 29 ›› Issue (4): 611-617.DOI: 10.3969/j.issn.1004-1524.2017.04.14

• Plant Protection • Previous Articles     Next Articles

Molecular variation and genetic diversity analysis of coat protein gene in Sweetpoviruses in China

ZHANG Chengling, SUN Houjun, YANG Dongjing, XU Zhen, ZHAO Yongqiang, XIE Yiping*   

  1. Xuzhou Institute of Agricultural Sciences in Jiangsu Xuhuai Area, Key laboratory of Biology and Genetic Improvement of Sweet potato, Ministry of Agriculture, Xuzhou 221131, China
  • Received:2016-11-28 Online:2017-04-20 Published:2017-04-27

Abstract: The objectives of this study were to study the gene and gene variation of Sweetpoviruses infecting Ipomoea batatas in China. Sweetpovirus coat protein gene fragments of 24 isolates from sweet potato were amplified by PCR using the infected leaf samples randomly collected from sweet potato research center and SDT, DnaSP, RDP3, MEGA and other software were used to analysis testifies. The result showed that, the nucleotide sequences and amino acid sequences showed similarieties of 88.3%-100% and 94.5%-100%, respectively for the 24 isolates containing 765 base pairs and 254 amino acids. Phylogenetic trees constructed with all Chinese isolates revealed that the isolates were divided into 2 groups. Group I included most of the isolates collected from China, and 22 isolates obtained in this study, and divided into 2 subgroups. Group Ⅱ included only 27 isolates from Genbank and 2 isolates, XU8_2 and XU8_3 obtained in this study, so these 2 isolates might be new species. The ratio between mutations in the nonsynonymous and synonymous sites (dN/dS ratio) of cp was>1, implying the coat protein gene was under positive selection. The shapes of mismatch distribution of Sweetpoviruses for all groups and subgroups except subgroup I were multimodal and ragged, indicating that all these population/subpopulations were long-existing ones.

Key words: Sweetpovirus, coat protein gene, molecular variation, genetic diversity

CLC Number: