Molecular markers of two sympatric species of the genus Frankliniella (Thysanoptera: Thripidae)

The genus Frankliniella is comprised of ubiquitous polyphagous insects that inflict losses on vegetable, fruit and ornamental crops. It is known that 5 species of this genus transmit tospoviruses to a wide variety of plant species. Two of these species, F. occidentalis and F. intonsa, occur sympatrically in Korea. These species cannot be easily identified based on morphological characters during their early larval stages. To solve this difficulty, molecular markers were developed in this study. PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) marker, Dde I, was identified at a polymorphic site in mitochondrial cytochrome b region. Although the identified sequences were highly similar to other known cytochrome b sequences, there was some variation between these two species. In addition, another marker was developed using PCR-RAPD (rapid amplified polymorphic DNA bands). PCR using the RAPD marker developed here resulted in the production of different product patterns by these two species, which could be used to determine if the samples were contaminated.