Matriarchal genetic structure of Reticulitermes (Isoptera : Rhinotermitidae) populations

We conducted the first extensive population genetics study of sympatric sub terranean termite populations of the genus Reticulitermes (Isoptera: Rhinot ermitidae) in which maternal gene flow across a large and varied geography was examined. Mitochondrial DNA (mtDNA) was chosen as a molecular marker be cause each termite colony is founded by a single diploid pair to whom all p rogeny are related. Each colony, therefore, carries the unique mtDNA of the foundress. Also, gene dispersion is limited to swarming or budding, neithe r of which results in long distance dispersion. Intra- and interspecific po pulation subdivision was expected, therefore, to be geographically localize d with colonies related by distance: the closer the more related. Species u sed in the study, Reticulitermes flavipes and R. virginicus, are sympatric and continuously distributed throughout the state of Georgia, U.S.A., a lar ge and geographically diverse area. Further, colony sites cover four soil p rovinces and most have been regularly monitored for at least three years. S eventy-eight individuals were sampled from 21 Georgia colony sites and one Canadian colony site for comparison. Amplified mtDNA fragments were sequenc ed from each individual in both directions. Phylogenetic relationships were then inferred using cladistic and phenetic methods. Both methods different iated species but demonstrated low levels of molecular divergence among R. flavipes populations. Lineages were, therefore, difficult to resolve for th is species. Reticulitermes flavipes and R. virginicus populations were also significantly different genetically according to the Hudson, Boos and Kapl an (HBK) statistic, R. flavipes geographic populations, however, were not. Assumptions of intraspecific relatedness, therefore, cannot be based on geo graphic locations in Georgia as expected.