Partial Biological and Molecular Characterization of Citrus psorosis virus Infecting Satsuma mandarin (Citrus unshiu Marc) in the east of Mazandaran province

A disorder on Satsuma mandarin, Citrus unshiu (Yu.Tanaka ex Swingle) trees with bark scaling of the trunk, ring spot or mosaic pattern symptoms on mature fruits especially around the calyx and extended yellow ring spot on the old leaves observed over the recent years in Mazandaran province. The results of virus mechanical inoculation on Gomphrena globosa indicator plants and indexing on different citrus stock and biological properties of the studied isolates indicated the presence of the type B citrus psorosis virus in samples. Molecular detection of CPsV was done by using RT-PCR and specific designed primers in which a desired amplicon with a size about 600bp amplified in infected samples collected from the orchards and greenhouse. Phylogenetic analysis of the representative isolates on the basis of nucleotide sequences of the CPsV-coat protein, categorized the representative isolates into two distinct groups which the group one further divided into three subgroups. Iranian isolates were clustered in the second subgroup beside the Americans and Japanese isolates and showed the lowest identity with the isolates from Latin American and African countries