Molecular diagnostics of the formosan subterranean termite (Isoptera: Rhinotermitidae)

Formosan subterranean termite, Coptotermes formosanus Shriaki, is a serious pest of structures in portions of United States. A 467-bp region of the mtDNA 16S rRNA gene was subjected to DNA sequencing from 12 Coptotermes species, including 64 populations of C. formosanus. Genetic diversity among species ranged from 1.8% to 7.0%, with C. formosanus at least 3.0% divergent to the other Coptotermes taxa. No genetic variation was detected among the C. formosanus populations for this marker making it ideal for diagnostics. Comparison of nucleotide sequence of mitochondrial rRNA 16S was used to design polymerase chain reaction (PCR) primers specific for C. formosanus. The diagnostic assay consists of two independent PCR runs of the 16S primer pair along with the C. formosanus primer set. PCR product from samples that are not C. formosanus can be subjected to DNA sequencing and compared with the database of termite 16S sequences on GenBank for identification. This technique provides a non-morphological method to identify field collected termites and may facilitate future quarantine programs for C. formosanus.