| Limited information exists on genetic variation and distribution of Reticulitermes from the south central United States: Texas, Oklahoma, Arkansas, and Louisiana.{09}A molecular genetics study, involving DNA sequencing of a portion of the mitochondrial DNA 16S gene, was undertaken to determine the extent of genetic variation with Reticulitermes spp., their respective distributions, and their phylogenetic relationships from this region. From 42 Texas counties a total of 68 R. flavipes , seven R. hageni, eight R. virginicus, and nine R. tibialis were identified. No genetic variation was observed in R. virginicus and R. hageni, whereas seven haplotypes were observed in R. tibialis and 13 for R. flavipes. Among the 13 R. flavipes haplotypes, 9 nucleotides were variable and genetic variation ranged from 0.2 to 1.6%. Phylogenetic analysis did not reveal any relationships among the R. tibialis and R. flavipes haplotypes, and there was no apparent geographical structure to the haplotypes. From 16 Oklahoma counties, 43 R. flavipes, four R. hageni , one R. virginicus, and seven R. tibialis samples were collected, identified and subjected to DNA sequencing. No genetic variation was observed in R. virginicus, whereas two haplotypes were observed in R. hageni, four in R. tibialis, and 10 for R. flavipes. Among the 10 R. flavipes haplotypes, nine nucleotides were variable and genetic variation ranged from 0.2 to 1.4%. From 35 Arkansas counties a total of 59 R. flavipes, 13 R. hageni, and seven R. virginicus were identified. In Arkansas, 11 mitochondrial haplotypes were observed in R. flavipes, three in R. hageni and three in R. virginicus. Among the 12 Louisiana parishes sampled, 13 R. flavipes, three R. virginicus , and one R. tibialis were identified with six, three, and one haplotypes for each species, respectively. Genetic variation among the R. flavipes haplotypes from both states ranged from 0.2 to 0.9%. Reticulitermes flavipes haplotype diversity observed in Arkansas and Louisiana was lower than in Texas and Oklahoma. The phylogenetic nature of Reticulitermes spp. from this region consistently demonstrates the monophyletic nature of each species. Our findings support morphological identities (of Reticulitermes) and clarify non-diagnostic castes, which could not be achieved otherwise. |
