Affiliation:
1. Emerging Pathogens Institute, Entomology and Nematology Department University of Florida Gainesville FL USA
2. US Department of Agriculture – Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology Gainesville FL USA
3. Department of Environmental Health Richardson Health Center Decatur GA USA
4. School of Forest Resources and Conservation, Institute of Food and Agricultural Sciences University of Florida Gainesville FL USA
5. VSN International Hemel Hempstead UK
Abstract
AbstractBACKGROUNDAn important component of the biological activity of pyrethroids, when used in disease vector control, is excito‐repellency. In this study, behavioral differences between insecticide susceptible (Orlando) and pyrethroid resistant (Puerto Rican) strains of Aedes aegypti were explored in a round glass arena using fabrics treated with permethrin, etofenprox, deltamethrin, or DDT. Repellency was evaluated across several variables, including the time to first flight (TFF), number of landings (NOL), total flight time (TFT), and maximum surface contact (MSC), all by video analysis.RESULTSResults from the Orlando strain indicated they were less likely than the Puerto Rican strain to tolerate tarsal contact with the treated fabrics. All four response variables indicated that the mosquito flight and landing behavior was most affected by pyrethroid resistance [knockdown resistance (kdr)] status. In other experiments, mosquitoes were surgically altered, with antennae ablated bilaterally, and these mosquitoes were more likely to stay on the treated surfaces for longer periods of time, irrespective of any chemical exposure. There were also differences in the responses to antennal ablation between the two strains of mosquitoes, indicating that resistance factors, probably kdr, influence the reactivity of mosquitoes to pyrethroid and DDT treatments, and that it was not completely negated by antennal ablation.CONCLUSIONSThese findings confirm the role of antennal olfactory components in the expression of excito‐repellent behaviors, and also support the hypothesis that excito‐repellency from pyrethroid/DDT exposure is probably due to a combination of sublethal neurotoxic excitation and interactions with the olfactory system. © 2023 Society of Chemical Industry.
Funder
U.S. Department of Agriculture
U.S. Department of Defense
Subject
Insect Science,Agronomy and Crop Science,General Medicine