title: Low genetic diversity among Cucumber vein yellowing virus isolates from Spain.
abstract: The population structure and genetic diversity of Cucumber vein yellowing virus (CVYV) from Spain were estimated by analyses of partial nucleotide sequences of the P1-proteinase (P1-Pro), P3 protein (P3), and the coat protein (CP) coding regions. Analysis of 56 CVYV Spanish field isolates collected from 2001 to 2005 showed low genetic diversity (0.0026, 0.0013, and 0.0012 for the P1-Pro, P3, and CP regions, respectively). The ratio between nonsynonymous and synonymous substitutions was among the lowest found in a plant virus, indicating a strong negative selective pressure in the regions analyzed. Nonsynonymous nucleotide substitutions were only found within the P1-Pro regions, although these do not appear to have been selected with time. The results support the hypothesis that the Spanish CVYV population could derive from a single origin of recent introduction.
authors.affiliation: Centro de Investigación y Formación Agraria, I.F.A.P.A., C.I.C.E. (Junta de Andalucía), Autovía del Mediterraneo Km 420, 04745 La Mojonera, Almeria, Spain. dirkjanssen@telefonica.net
authors.forename: Dirk
authors.initials: D
authors.lastname: Janssen
authors.forename: Leonardo
authors.initials: L
authors.lastname: Velasco
authors.forename: Germán
authors.initials: G
authors.lastname: Martín
authors.forename: Eduardo
authors.initials: E
authors.lastname: Segundo
authors.forename: Isabel Maria
authors.initials: IM
authors.lastname: Cuadrado
mesh_terms: D018553:Cucumis sativus / Q000821:virology*; D014644:Genetic Variation; D016679:Genome, Viral; D019176:Potyviridae / Q000235:genetics* / Q000302:isolation & purification; D017422:Sequence Analysis, DNA; D013030:Spain