The phylogeny of thrips (Thysanoptera: Thripidae) based on partial sequences of cytochrome oxidase I, 28S ribosomal DNA and elongation factor-1α and the association with vector competence of tospoviruses

The phylogenetic relationships among 16 species including 10 thrips vector species of tospoviruses were analysed using partial sequences of three genes: mitochondrial COI, nuclear 28S ribosomal DNA and the elongation factor-1 alpha (EF-1 alpha) in order to reveal the influence of lineage among thrips vector species on the vector competence of tospoviruses. The phylogenetic trees of thrips suggested that distinct clades were formed between the genera Frankliniella and Thrips including vector species at least in combined nuclear DNA data, although COI data showed a similar result despite low bootstrap value in the root of Thrips clade. Scirtothrips had an ambiguous phylogenetic position in this study. Vector and non-vector species were found within the same clade in the genus Thrips. Compared with the phylogenetic tree of thrips, the virus phylogeny inferred from the nucleocapsid (N) protein sequence were likely to correspond to the phylogeny of thrips, genera Frankliniella, Thrips and Scirtothrips, respectively, and also to the primary host plants under natural conditions. These results suggested that the vector competence of thrips for tospoviruses might be influenced by the lineages of thrips vectors as well as host plants.