Background: Strawberry crinkle virus (SCV) is a member of the genus Cytorhabdovirus, family Rhabdovirida, and order Mononegavirales. SCV affects the production of various strawberry cultivars. In this study we investigated the genetic diversity of SCV in strawberry fields based on P3 (movement protein) gene. Methods and Results: The samples were collected from strawberry fields in the Kurdistan Province, Iran. P3 gene from 20 SCV isolates, representing 18 nucleic acid haplotypes, is composed of 729 nucleotides, encoding a protein with 243 amino acids. SCV isolates shared small nucleotide (98.77 - 99.86%) and amino acid (97.5 - 100%) sequence identity. Phylogenetic analyses of the new P3 sequences with two previously published SCV-P3 sequences from the Czech Republic showed that there are two major phylogroups (I and II) and three minor phylogroups in the body of the phylogeny, I-1, I-2, II-1. Comparisons of P3 gene sequences revealed a mutational bias, with more differences being transitions than transversions. The ratio of non-synonymous/synonymous nucleotide changes was < 1, indicating that SCV P3 gene is under predominantly negative selection. Conclusions: Phylogenetic and sequence identity analyses showed that SCV isolates from Iran are closely related and have not diverged more than 2% based on P3 gene despite geographical separation and strawberry cultivar. This is the first report of the genetic diversity of SCV worldwide.
