Population genetics of the solanum fruit fly, Bactrocera latifrons (Hendel) (Diptera: Tephritidae)

The solanum fruit fly, Bactrocera latifrons (Hendel), is an important pest species of commercial plants in the family Solanaceae. In this study, the population genetic structure of B. latifrons was investigated using mitochondrial cytochrome c oxidase I sequences. A mitochondrial DNA haplotype network revealed no major genetic break, but haplotypes from recently invaded areas in Japan, Tanzania, and Kenya were genetically divergent. The overall haplotype network is approximately star-shaped, characteristic of recent demographic expansion of populations. This is also supported by large negative values of neutrality tests. Despite the overall pattern of recent population history, genetic structure analysis revealed considerable genetic structuring with 33% of pairwise comparisons being significantly different. Populations that were genetically different from the others usually possess low genetic diversity, suggesting that genetic drift is potentially a factor driving genetic differentiation. Local extinction and recolonization processes related to the availability of host plants are most likely responsible for a founder effect and subsequent genetic drift in a population.