A cytochrome P450 gene involved in methidathion resistance in Amblyseius womersleyi Schicha (Acari: Phytoseiidae)

This study reports on a CYP4 gene possibly involved in methidathion resistance in Amblyseius womersleyi Schicha. This is the first report on a CYP4 gene from a phytoseiid mite. Four different CYP4 genes (CYP4-a, CYP4-b, CYP4-c, and CYP4-d) were detected in this predaceous mites. No differences in CYP4 expression levels were detected for the strains Ishigaki S, Kanaya S (methidathion susceptible strains) and Kanaya R (methidathion resistant strain), using RT-PCR method for CYP4-a, CYP4-b, and CYP4-c. In the case of CYP4-d, the expression level in Kanaya R was significantly higher than in susceptible strains. Studies using RT-PCR indicated that CYP4-d gene is expressed in all stages of A. womersleyi, with a little higher expression in protonymph, deutonymph and adult, in comparison to egg and larva. Significant correlation between CYP4-d expression and monooxygenase activity was observed for the different strains and life stages of A. womersleyi.