Cross ‐resistance and genetics of field‐evolved resistance to chlorfenapyr in Plutella xylostella

Field-derived high-level resistance to chlorfenapyr inPlutella xylostella was autosomal, incompletely dominant, and controlled by monofactor. Lack of cross-resistance highlights the importance of rotation of chlorfenapyr and other insecticides. AbstractChlorfenapyr is a broad-spectrum halogenated pyrrole insecticide with a unique mode of action. Due to the misuse and overuse of this chemical, resistance has been reported in several arthropods, includingPlutella xylostella, which is one of the most destructive insect pests afflicting crucifers worldwide. A better understanding of the cross-resistance and genetics of field-evolved chlorfenapyr resistance could effectively guide resistance management practices. Here, the chlorfenapyr resistance of a field-derived population ofP. xylostella was introgressed into the susceptible IPP-S strain using a selection-assisted multigenerational backcrossing approach. The constructed near-isogenic strain, TH-BC5F2, shared 98.4% genetic background with the recurrent parent IPP-S strain. The TH-BC5F2 strain showed 275-fold resistance to chlorfenapyr, but no significant cross-resistance to spinosad, abamectin, chlorpyrifos, β-cypermethrin, indoxacarb, chlorantraniliprole, or broflanilide (no more than 4.2-fold). Genetic analysis revealed that resistance was autosomal, incompletely dominant, and conferred by 1 major gene or a few tightly linked loci. The synergism of metabolic inhibitors (PBO, DEM, and DEF) to chlorfen apyr was very weak (<...
Source: Insect Science - Category: Biology Authors: Tags: ORIGINAL ARTICLE Source Type: research