D3318: Development of a loop-mediated isothermal amplification assay for the fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae), using species-specific sequences

The fall armyworm (FAW), Spodoptera frugiperda (Lepidoptera: Noctuidae), which is native to tropical and subtropical regions of the Western Hemisphere is now annually arrives in Korea from China with the assistance of seasonal wind. Ubiquitous crop fields, particularly corn fields in nationwide South Korea are now target places for blocking their entry and subsequent development. To achieve the goal of complete eradiation prompt identification in nationwide crop fields is essential. Thus, in this study, we are in the middle of developing loop-mediated isothermal amplification (LAMP) assay, one of the main merits of which is a rapid identification of target species. To design LAMP primers whole genomes were sequenced by Next-Generation Sequencing method for one FAW and 13 lepidopteran species, composed of seven corn-occurring species and six Spodoptera species, and found 158 regions specific to FAW. As a first batch of experiment we randomly selected and tested 11 loci. Among them five loci provided consistent amplification reaction in five loci when ten FAWs, which were collected from eight localities in four countries (Korea, USA, Vietnam, and Zimbabwe) were tested, whereas the 13 non-target lepidopteran species were not amplified. To increase in-field applicability of the method all life stages, reaction time, and stability of pre-mixed primer plus isothermal master mixture will be tested using the quick extracted DNA.