The mitochondrial 12S rRNA gene was amplified, cloned, and sequenced from the phytoseiids Neoseiulus fallacis, N. californicus, N. cucumeris, Metaseiulus occidentalis, Iphiseius degenerans and Phytoseiulus persimilis. The sequence divergences detected between these phytoseiids were much higher at the mitochondrial 12S rRNA gene locus (9.5 to 45%) than the nuclear rRNA internal transcribed spacer region (ITS-1, 5.8S and ITS-2) (1.2 to 23%). This allowed us to design a 'molecular ladder assay' that amplifies a diagnostically different sized DNA band from each of the six phytoseiids using species-specific primers designed from the variable regions of the 12S rRNA gene. Reliable amplification by Standard PCR was possible only when DNA was prepared by a PUREGENE method from multiple specimens (>20 females). By contrast, Long PCR, which uses two DNA polymerases (Taq and Pwo), was found to amplify mitochondrial 12S rRNA gene sequences consistently from single females, males, nymphs, larvae or eggs when DNA was extracted in Chelex
Keywords: Biological Control
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA