Molecular characterization and phylogenetic relationships of two new bipartite begomovirus infecting malvaceous plants in Yucatan, Mexico.

摘要

Sida acuta and Corchorus siliquosus plants showing yellow mosaic and yellow vein symptoms, respectively, were collected in the Yucatan Peninsula, Mexico. Total DNA was isolated from both plant species and used for the amplification, cloning, and sequencing of the Begomovirus genome. Nucleotide comparison of the complete DNA-A component isolated from S. acuta and C. siliquosus confirmed the presence of two distinct begomoviruses species. Based on phenotypic symptoms observed in infected field plants, the names Sida yellow mosaic Yucatan virus (SiYMYuV) and Corchorus yellow vein Yucatan virus (CoYVYuV) were proposed. The SiYMYuV DNA-A shared the highest nucleotide identity (86%) with the Okra yellow mosaic Mexico virus (OkYMMV). The complete DNA-B component shared the highest nucleotide identity (80%) with CoYVYuV. The CoYVYuV DNA-A shared the highest nucleotide identity (84%) with SiYMYuV. The 166-nt common region (CR) sequence for the DNA-A and DNA-B components of SiYMYuV shared a high nucleotide identity of 99%, and the 151 nt of CoYVYuV CR shared 95% of nucleotide identity. The organization and the iterated sequence of the putative AC1 binding site (located within the common region) of both isolates, were similar to that of the begomoviruses of the Western Hemisphere. Phylogenetic analyses placed the DNA-A and DNA-B of SiYMYuV and CoYVYuV in the clade containing the Abutilon mosaic virus (AbMV).