Genetic Diversity and DNA Barcoding of Thrips in Bangladesh

Simple Summary Thrips, the notorious sap-sucking insects, serve as the vector of plant viruses. Their accurate species identification is essential for determining the vector species and implementing successful pest management techniques. Mitochondrial COI (DNA barcode) sequence variation has proven to be effective in identifying species in many insect pest groups. In this study, we identified 19 thrips species that were found on different host plants in Bangladesh. Among the 19 species, we identified four prominent vector species (Frankliniella intonsa, Thrips tabaci, Scirtothrips dorsalis and T. palmi) and one significant pollinator, Microcephalothrips abdominalis. The findings presented here emphasize the importance of conducting DNA barcoding, analyzing population structure, and assessing the genetic diversity of thrips species in this region. This research is crucial for comprehending their host preferences, potential for adaptation, and genetic variation at both local and regional levels. Accurate identification of pests and invasive species is essential for implementing effective control and quarantine measures. Misidentifications can lead to the application of ineffective control strategies.Abstract Thrips are economically important pests, and some species transmit plant viruses that are widely distributed and can damage vegetables and cash crops. Although few studies on thrips species have been conducted in Bangladesh, the variation and genetic diversity of thrips species remain unknown. In this study, we collected thrips samples from 16 geographical locations throughout the country and determined the nucleotide sequences of the mitochondrial cytochrome c oxidase subunit 1 (mtCOI) gene in 207 thrips individuals. Phylogenetic analysis revealed ten genera (Thrips, Haplothrips, Megalothrips, Scirtothrips, Frankliniella, Dendrothripoides, Astrothrips, Microcephalothrips, Ayyaria, and Bathrips) and 19 species of thrips to inhabit Bangladesh. Among these, ten species had not been previously reported in Bangladesh. Intraspecific genetic variation was diverse for each species. Notably, Thrips palmi was the most genetically diverse species, containing 14 haplotypes. The Mantel test revealed no correlation between genetic and geographical distances. This study revealed that thrips species are expanding their host ranges and geographical distributions, which provides valuable insights into monitoring the diversity of and control strategies for these pests.