title: Molecular genetic analysis and evolution of begomoviruses and betasatellites causing yellow mosaic disease of bhendi.
abstract: In India, Bhendi yellow vein mosaic disease (BYVMD) is one of the most economically important diseases of bhendi/okra and is caused by a complex of monopartite begomovirus (Bhendi yellow vein mosaic virus-BYVMV) and betasatellite (Bhendi yellow vein betasatellite-BYVB). In this study, we have analyzed the role of possible evolutionary factors involved in the evolution of BYVMV and BYVB isolates. Evidence of inter-species and inter-strain recombination events was detected among the viral isolates, and majority of these recombinant isolates possess microsatellites in their genome. Recombination analysis suggests that cotton-infecting and bhendi-infecting begomoviruses probably share a recent common ancestor. In addition to genetic differentiation and gene flow, high degree of genetic variability was detected among the viral population. A strong purifying selection seems to be acting on the viral coding regions. The nucleotide substitution rate of V1 gene (for BYVMV) and βC1 gene (for BYVB) was estimated to be 7.55 × 10-4and 2.25 × 10-3nucleotide substitutions/site/year, respectively. The present study underlines that the evolution of BYVMD-associated viral components is driven by selection acting on the genetic variation generated by recombination and mutation.
authors.affiliation: Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India.
authors.forename: R Vinoth
authors.initials: RV
authors.lastname: Kumar
authors.affiliation: Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India.
authors.forename: H C
authors.initials: HC
authors.lastname: Prasanna
authors.affiliation: Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India.|Indian Institute of Vegetable Research, Varanasi, Uttar Pradesh, India.
authors.forename: A K
authors.initials: AK
authors.lastname: Singh
authors.affiliation: Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India.
authors.forename: D
authors.initials: D
authors.lastname: Ragunathan
authors.affiliation: Krishidhan Research Foundation Private Limited, Jalna, Maharashtra, India.
authors.forename: G K
authors.initials: GK
authors.lastname: Garg
authors.affiliation: Molecular Virology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi, 110 067, India. supriyachakrasls@yahoo.com.
authors.forename: S
authors.initials: S
authors.lastname: Chakraborty
mesh_terms: D028483:Abelmoschus / Q000235:genetics* / Q000821:virology; D053839:Begomovirus / Q000235:genetics* / Q000472:pathogenicity; D007194:India; D008969:Molecular Sequence Data; D010802:Phylogeny; D010935:Plant Diseases / Q000235:genetics / Q000821:virology*
keywords: Begomovirus; Betasatellite; Geminiviridae; Microsatellite; Nucleotide diversity; Recombination