Molecular Diversity of Two-Spotted Spider Mite (Tetranychus urticae) in Apple Orchards across Poland and its Potential Link with the Resistance to Meti-Acaricides

Two-spotted spider mite (Tetranychus urticae, Koch) possess tremendous ability to develop resistance to pest control chemicals. Hence, although METI-acaricides are quite new group of pesticides, the resistance to this chemicals may shortly become a serious obstacle in two-spotted spider mite management. In presented study, molecular and phenotypic diversity of three laboratory strains and seven T. urticae populations collected from pest-protected apple orchards were analysed in reference to METI-acaricides resistance. The inter-population molecular diversity analysis with a set of RAPD markers revealed 6 populations to be in close relation to susceptible reference strain (GSS). Only one population turned out to be linked relatively close with METI-acaricides resistant strain (Akita). Simultaneously, the results of biological test showed similar relation among the analysed populations, according to the resistance incidence ratio. Obtained results suggest that METI-acaricides resistance trait in two-spotted spider mite is likely to be determined at genomic level and may be considered as an initial stage for developing molecular biology tools for early detection of METI-acaricides resistance in T. urticae populations. © 2019 Tomasz Jȩcz et al.