title: Prevalence of Tobacco mosaic virus in Iran and Evolutionary Analyses of the Coat Protein Gene.
abstract: The incidence and distribution of Tobacco mosaic virus (TMV) and related tobamoviruses was determined using an enzyme-linked immunosorbent assay on 1,926 symptomatic horticultural crops and 107 asymptomatic weed samples collected from 78 highly infected fields in the major horticultural crop-producing areas in 17 provinces throughout Iran. The results were confirmed by host range studies and reverse transcription-polymerase chain reaction. The overall incidence of infection by these viruses in symptomatic plants was 11.3%. The coat protein (CP) gene sequences of a number of isolates were determined and disclosed to be a high identity (up to 100%) among the Iranian isolates. Phylogenetic analysis of all known TMV CP genes showed three clades on the basis of nucleotide sequences with all Iranian isolates distinctly clustered in clade II. Analysis using the complete CP amino acid sequence showed one clade with two subgroups, IA and IB, with Iranian isolates in both subgroups. The nucleotide diversity within each sub-group was very low, but higher between the two clades. No correlation was found between genetic distance and geographical origin or host species of isolation. Statistical analyses suggested a negative selection and demonstrated the occurrence of gene flow from the isolates in other clades to the Iranian population.
authors.affiliation: Department of Plant Pathology, College of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran 14515-775, Iran.
authors.forename: Athar
authors.initials: A
authors.lastname: Alishiri
authors.affiliation: Department of Plant Pathology, College of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran 14515-775, Iran.
authors.forename: Farshad
authors.initials: F
authors.lastname: Rakhshandehroo
authors.affiliation: Department of Plant Pathology, College of Agriculture and Natural Resources, Science and Research Branch, Islamic Azad University, Tehran 14515-775, Iran.
authors.forename: Hamid-Reza
authors.initials: HR
authors.lastname: Zamanizadeh
authors.affiliation: Department of Horticultural Sciences, Seoul Women's University, Seoul 139-774, Korea.
authors.forename: Peter
authors.initials: P
authors.lastname: Palukaitis
keywords: TMV; Tobamovirus; coat protein; gene flow; phylogeny