Related Experiment Video
Updated: Jan 21, 2026

A Method for Screening and Validation of Resistant Mutations Against Kinase Inhibitors
Published on: December 7, 2014
Pyrethroid resistance in the pest mite, Halotydeus destructor: Dominance patterns and a new method for resistance
Xuan Cheng1, Paul A Umina2, Siu Fai Lee3
1School of BioSciences, Bio21 Institute, The University of Melbourne, Victoria 3010, Australia.
Abstract:
An L1024F substitution in the para gene, which encodes a subunit of the voltage-gated sodium channel, has been implicated in pyrethroid resistance in a mite pest, Halotydeus destructor, which attacks rape and other grain crops. A high-resolution melt (HRM) genotyping assay was developed for testing the relative pyrethroid susceptibility of different para genotypes and for high-throughput field screening of resistant alleles. The L1024F mutation was found to be incompletely recessive in phenotypic laboratory bioassays with the pyrethroid pesticide, bifenthrin. While the resistance ratio of heterozygotes (RS) to susceptible homozygotes (SS) was <6 in 24 h bioassays, the resistant homozygotes (RR) (with a resistance ratio > 200,000) survived the recommended field rate of bifenthrin (100 mgL-1). HRM genotyping of mites from field populations across Australia indicated the presence of resistant alleles in Western Australia and South Australia, but not in Victoria and New South Wales. The assay developed will be useful for routine screening of pyrethroid resistance, and the dominance relationships established here point to useful resistance management strategies involving the maintenance of reservoirs of susceptible mites to dilute resistant homozygotes in a population.
Related Concept Videos
Resistivity
Resistance
Resistance and Conductance
Various factors impact the resistance of a conductor. Spiraling in stranded conductors increases their...
Equivalent Resistance
Vascular Resistance
The primary determinants of vascular resistance are vessel diameter, blood viscosity, and vessel length. Among these, vessel diameter plays the most significant role due to the fourth power relationship described by...
Rolling Resistance
For instance, imagine a hard cylinder rolling on a comparatively soft surface. The cylinder's weight compresses the surface beneath it. As the cylinder moves, the material in front of it slows down due to...

