First, fourth, fifth, sixth, and seventh authors: Station de Pathologie Végétale, Institut National de la Recherche Agronomique, F-84143 Montfavet cedex, France; and second and third authors: Unité de Génétique et d'Amélioration des Fruits et Légumes, Institut National de la Recherche Agronomique, F-84143 Montfavet cedex, France
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Accepted for publication 26 October 2004.
Variability within the pepper-infecting potyviruses Pepper veinal mottle virus (PVMV) and Chili veinal mottle virus (ChiVMV) in Africa and Asia was investigated. Coat protein (CP) gene sequence diversity revealed three clades that corresponded to three geographic locations and there was no evidence of presence of the ChiVMV/Asian group in western or central Africa. These clades included closely related isolates that potentially belong to two viral species, which is consistent with current nomenclature. These clades could not be unambiguously identified with polyclonal antisera; however, reverse transcription-polymerase chain reactions allowed differentiation of the isolates into two species based on a large indel in the CP gene. PVMV and ChiVMV isolates were classified into three and two pathotypes, respectively, in relation to pepper genotypes carrying different resistance factors. Specificity of resistance only partially corresponded to molecular diversity of the isolates. Only one isolate of PVMV could infect pepper genotypes carrying the two recessive genes pvr6 and pvr2
2; however, these genotypes were not infected by PVMV in field trials in Senegal, despite a high prevalence of PVMV in the surrounding pepper plants.
The American Phytopathological Society, 2005