Application of DNA microarray technology for the simultaneous identification of agricultural <i>Frankliniella</i> thrips (Thysanoptera: Thripidae)

Thrips (Insecta: Thysanoptera) are polyphagous insects that feed on various crops. Among them, species within the genus Frankliniella are particularly notorious pests and are subject to quarantine regulations globally. To facilitate rapid identification, species-specific primers based on polymerase chain reaction methods have been developed for certain Frankliniella species. Over the past decade, DNA microarray technology has become a valuable tool for the simultaneous identification of multiple insect pests. In this study, we used DNA microarray technology to identify 10 Frankliniella species. For each species, 4 to 8 species-specific probes were designed on the basis of nuclear ribosomal internal transcribed spacer 2 sequences. The analysis included adults and nymphs collected from agricultural products imported from 15 countries. A total of 62 species-specific probes were successfully developed for the identification of Frankliniella species. All probes demonstrated 100% specificity, except for Ffus_1D, which exhibited cross-hybridization with other Frankliniella species due to sequence similarity. The probes achieved high efficiency (more than 90%) in most cases. In addition, no signals were detected for 6 nontarget thrips species from different genera. However, some probes exhibited weak signal intensity, likely due to intraspecific variations in the internal transcribed spacer 2 sequence. The use of multiple species-specific probes can minimize the false-positive rate. Compared with single species-specific primers, which can identify only a few species, DNA microarray technology offers a reliable and efficient solution for the simultaneous identification of multiple thrips species.