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Phylogeography of Diabrotica virgifera LeConte and Diabrotica virgifera zeae Krysan and Smith (Coleoptera: Chrysomelidae)
Diabrotica virgifera zeae, and D. virgifera virgifera are currently classified as subspecies; both are key pests of maize. D. v. zeae is distributed from Central America to Oklahoma in the United States. D. v. virgifera is found from northern Mexico to southeastern Canada. This study was conducted to infer the pattern of intraspecific variation in the mtDNA COI and the pattern of Wolbachia infection in D. virgifera (sensu lato) in Central and North America to reconstruct the history of differentiation and expansion of living populations of the species. Nested Clade Phylogeographic Analysis (NCPA) and phylogenetic analysis of mtDNA sequence data collectively supported the geographic separation of D. virgifera into two phylogroups along a North-South axis. The clades do not geographically correlate with the distribution of the subspecies based on color patterns indicating that there is not a significant genetic association of COI mtDNA and color in this species. Phylogeographic patterns support the working hypothesis that the origin of D. virgifera was in Central America or Mexico and that dispersal of D. virgifera followed the movement of domesticated corn into the southwestern United States. NCPA also recovered in part the well-documented recent geographic dispersion history of D. v. virgifera in the United States. A different A division strain of Wolbachia was found in D. v. zeae in Mexico vs. strains present in D. v. virgifera in the United States. The geographic distribution of Wolbachia in D. virgifera was poorly correlated with D. virgifera COI mtDNA subdivision patterns over the geographic area included in this study. Therefore, these patterns do not support the hypothesis that Wolbachia may be greatly reducing gene flow and acting as a speciation agent between the subspecies. This study demonstrates that phylogeographic analysis can be used to address evolutionary questions in an applied system. In this case, cultivation and spread of a domesticated plant for human use appeared to have facilitated the dispersal of a native insect into new geographical areas. ^
Biology, Molecular|Biology, Ecology|Biology, Entomology
Segura-Leon, Obdulia L, "Phylogeography of Diabrotica virgifera LeConte and Diabrotica virgifera zeae Krysan and Smith (Coleoptera: Chrysomelidae)" (2004). ETD collection for University of Nebraska - Lincoln. AAI3159561.