Geographical distribution and incidence of pesticide resistance mutations in spider mite and thrips species from North Vietnam

Spider mites and thrips are major agricultural pests worldwide. Despite their well-documented impact on crop yields in South-East Asia, their species composition, distribution, and pesticide susceptibility remain poorly studied in the region. This study focused on the Red River Delta region of Vietnam. Multiple populations of spider mites and thrips were collected and subjected to phylogenetic analysis for reliable species identification. For the first time, Tetranychus evansi and Tetranychus pueraricola were reported in Vietnam. All thrips populations were found to belong to the Thrips palmi cryptic species complex, with identification conducted at the clade level. Several well-characterized resistance mutations, useful as molecular diagnostic markers, were identified in both pest groups. Additionally, multiple candidate resistance mutations were reported for the first time in spider mites and their possible role in resistance is discussed. These findings highlight the importance of carefully selecting pesticides, as many field populations may already be resistant to several active ingredients. The results highlight an urgent need for resistance management strategies and the adoption of alternative control methods.