Objective:
The main mechanism of pyrethroid resistance in the southern cattle tick, Boophilus microplus, throughout Mexico is a mutation in the sodium channel gene that reduces the target site affinity of pyrethroid acaricides. By silencing the gene that produced the mutated sodium channel it is theoretically possible to render pyrethroid-resistant ticks susceptible to pyrethroid acaricides and thus saving this valuable and relatively safe acaricide.

Approach:
Homozygous, heterozygous, and susceptible engorged female ticks will be injected using standard RNAi technique. Larvae from injected females will be analyzed with bioassay and PCR to determine the phenotypic response to pyrethroid exposure versus the genotype of the individuals tested.