Nucleotide Sequence and Phylogenetic Analysis of Coat Protein Gene of Two Iranian Watermelon Mosaic Virus Isolates

Watermelon mosaic virus (WMV) is a member of the genus Potyvirus in the family Potyiviridae. This virus is one of the most common and widespread viruses infecting cucurbits worldwide. In this research, partial biological and molecular characteristics of two WMV strains includingYAZ.WMV.41 and YAZ.WMV.55 collected from cucurbit growing farms in Yazd province were studied. These isolates did not react to polyclonal WMV antiserum in Direct and Indirect ELISA tests. Also, compared to several reported WMV isolates, these isolates induced different symptoms on the test plants. Coat protein (CP) gene (809 bp length) of these isolates was amplified in PCR, cloned and sequenced. Phylogenetic analysis showed that two Iranian and one previously reported WMV isolates (EU667626) are classified in subgroup IIB. Other Iranian isolates from the previous studies were clustered into sub groups I, IIA. Nucleotide sequence comparison indicated that these isolates share minimum and maximum nucleotide sequence identities (92.2 and 99.5 %) with a Spain (Accession no. AJ579518) and an Iranian (GQ421161) isolates, respectively. According to the results of this study, cucurbits are infected by different WMV isolates in Iran.