Thrips from the genus Frankliniella (Thysanoptera, Thripidae) are a serious insect pest of various crops, including vegetables, fruits and ornamental plants. Thrips cause significant economic damage plants directly by feeding, and indirectly by acting as vectors for the tospoviruses such as Tomato spotted wilt virus (TSWV) and Chrysanthemum stem necrosis virus (CSNV) in chrysanthemum. To investigate the associations of thrips with tospoviruses and their ability to transmit, we have developed a protocol for identifying tospovirus and thrips species simultaneously in an individual thrips sample was successfully conducted. Total RNA was extracted from thrips according to manufacturer’s insturctions of RNeasy mini kit (Quiagen co.), and then TSWV was identified by reverse transcription-polymerase chain reaction (RT-PCR) using TSWV specific primers for the N genes. The residual genomic DNA in thrips RNA extract was used as a template to identify thrips species by PCR using universal primers for ITS2 region and subsequently digesting the PCR product by an restriction enzyme (RsaI) In addition, a classification into the species of thrips was confirmed using the nucleotide sequence of PCR products. The developed protocol was applied to investigate the occurrence of viruliferous thrips species in thrips populations collected from chrysanthemum fields. In this study, most of thrips were identified to Frankliniella spp. and thirps that acquire TSWV was 14 % of 65 thrips.

Damages of medicinal crops by thrips and identification of thrips species were investigated on major medicinal crops, Platycodon grandiflorum, Schizandra chinensis, Codonopsis lanceolata, Lycium chinense, Bupleurum falcatum, Ledebouriella seseloides, Angelica gigas, Glycyrrhiza uralensis, Liriope platyphylla, Atractyloides sp., in Suwon, Eumseong, Jecheon, Pyeongchang, Chyungyang 2012. Thrips and their damages were found at all of the medicinal crops investigated, mostly occurring at early growing stages of each medicinal crop and causing apical meristem region withered, thereby inhibiting the growth of plants. As a result, Frankliniella intonsa, Thrips tabaci, and Megalurothrips distalis have been identified as dominant species on medicinal crops in open field, whereas Frankliniella occidentalis was restricted to Lycium chinense in which protected cultivation. Occurrence of thrips species on medicinal crops seems to be affected by host specificity and environmental factors such as cultivation types.