RNA3 of a Cucumber Mosaic Virus Strain Infecting Musa Basjoo Based on the Molecular Characterization of Its 5' UTR

摘要

This A strain of Cucumber mosaic virus (CMV), namely CMV-Mb, was detected from a naturally infected Musa basjoo (Mb) plant. After biological and serological tests, a full-length sequence of RNA3 was determined with products of RT-PCR. CMV-Mb RNA3 was found to be composed of 2189 nucleotides (nt). The results of sequence comparisons showed that CMV-Mb RNA3 formed an independent but highly supported clade within CMV subgroup II, revealing that CMV-Mb is derived from this subgroup but is a unique naturally homozygote strain. This strain may have evolved independently to infect Musa species, and its distribution may have been facilitated by the vegetative propagation of its host. It is considered that under vegetative propagation conditions, both host and geographical environment have impacted on evolutional types of this tripartite RNA virus.