Thermal consequences of pyrethroid knockdown resistance in the house fly, Musca domestica

The house fly is a common synanthropic pest, capable of transmitting over 100 known pathogens to both human and animal populations. Current control methods heavily favor utilizing a class of insecticides known as pyrethroids. Due to excessive use, however, mutations known formally as kdr (knockdown resistance) have become a consistent issue for control. kdr mutations are single-nucleotide polymorphisms in the para-sodium channel gene, the target site for pyrethroids. Similar mutations in the para-sodium channel gene, known are para-ts mutations, are well-characterized for the way they modify thermal tolerance in Drosophila melanogaster. Here we look at the effects of kdr on thermal tolerance in congenic strains of house flies with different kdr mutation variants, backcrossed into a common susceptible strain. Results demonstrate that kdr modifies thermal response in various ways. With this information, we hope that new control strategies can be developed that harness temperature as a biological advantage against this challenging pest. Furthermore, we hope to expand the knowledge of possible selective elements for and against tested kdr genes.