Molecular Phylogeny of Bactrocera Species (Diptera: Tephritidae: Dacini) Inferred from Mitochondrial Sequences of 16s rDNA and CO1 Sequences

摘要

Many fruit flies in the genus Bactrocera (Diptera: Tephritidae: Dacini) are economically important insects. However, little attention has been given to the molecular phylogenetic relationship among Bactrocera subgenera. We explored the phylogenetic relationship among the 8 subgenera Afrodacus, Austrodacus, Bactrocera, Daculus, Gymnodacus, Paratridacus, Tetradacus, and Zeugodacus based on the sequences of 2 mitochondrial DNA fragments with a combined length of 1034 base pairs. The 2 mtDNA fragments are a 689-bp segment of the COI gene and a 345-bp segment of the 16S rDNA gene. Thirty-five individuals representing 7 Bactrocera species found in the Chongqing region in China were sequenced for both fragments, and sequences of the same gene regions were acquired from GenBank for another 20 Bactrocera species and 2 other tephritid species, Anastrepha ludens and Ceratitis capitata, which were used as out-groups for the phylogenetic analyses. We reported Bactrocera (Tetradacus) minax and Bactrocera (Zeugodacus) diaphora sequences for the first time, and the subgenus Bactrocera (Tetradacus), here represented by B. (T.) minax and B. (T.) tsuneonis, was included for the first time in an analysis of the genus Bactrocera phylogeny Results of our analyses showed within-subgenus nucleotide diversity ranged from 9.1 to 19.0% among the subgenera, and the net divergence among subgenera ranged from 4.6 to 12.7%. Results of phylogenetic analyses based on maximum parsimony method supported that subgenus Bactrocera (Bactrocera) and Bactrocera (Zeugodacus) are paraphyletic. The subgenus Zeugodacus, Bactrocera (Zeugodacus) caudate, Bactrocera (Zeugodacus) diaphora, and Bactrocera (Zeugodacus) scutellata are closely related to Bactrocera (Zeugodacus) tau and Bactrocera (Zeugodacus) Cucurbitae. This results indicated that subgenus Austrodacus and Zeugodacus, which attack cucurbit plants, are closely related to species of the subgenus Afrodacus, Bactrocera, and Gymnodacus, which attack plants of numerous families. In addition, subgenus Paratridacus is a sister group to subgenus Tetradacus, and 7 species of the Bactrocera (Bactrocera) dorsalis complex (as defined by Drew & Hancock 1994) included in this study formed a monophyletic clade. Subgenus Daculus is 1lineage by itself, which does not fall into the Bactrocera group or Zeugodacus group.View this article in BioOne