Biology: Mosquitoes learn to avoid pesticides after single non-lethal exposure

 
A paper revealing that female mosquitoes once exposed to pesticides learn to avoid pesticides,Scientific Reports Will be published in.The books suggest that these mosquito behaviors may reduce the effectiveness of pesticides against mosquitoes.

Insecticides are used to control the spread of mosquito-borne diseases.Over the last few decades, the number of mosquitoes that have acquired pesticide resistance has increased, but it is not known to what extent it depends on the behavior of mosquitoes.

Frederic Tripet and colleagues now use common pesticides for mosquito control (malathion, propoxul, deltamethrin, permethrin, lambda-sihalotrin) to mediate dengue, zika and western aegypti. ) And Culex quinquefasciatus females were exposed to non-lethal doses of pesticides.They were then re-exposed to the same pesticides to see if they stopped eating and resting and to assess whether this would affect their survival.

Experiments were conducted in which the food source could only be reached through an insecticide-treated net.Pre-exposed mosquitoes were more likely to pass through the pesticide-treated net than mosquitoes not exposed to the pesticide.15.4% of Aedes aegypti and 12.1% of Culex quinquefatus that had been previously exposed to pesticides, 57.7% of Aedes aegypti and 54.4% of Aedes aegypti that had not been exposed to pesticides passed through this net.Also, when mosquitoes were exposed to pesticides using pesticide-treated nets and the subsequent survival rates were compared, the survival rates of mosquitoes previously exposed to pesticides were more than double that of unexposed mosquitoes. was.Only 2% of Aedes aegypti and 38.3% of Culex quinquefatus that were previously exposed to pesticides survived, whereas only 32.1% of Aedes aegypti and 11.5% of Culex quinquefatus that were not exposed survived.

In addition, Tripets and colleagues found that mosquitoes that were previously exposed to pesticides had a higher proportion of mosquitoes resting in containers that smelled of control substances than those that did not. It was revealed that it was expensive.75.7% of Aedes aegypti and 83.1% of Culex quinquefatus previously exposed to pesticides, 50.2% of Aedes aegypti and 50.4% of Aedes aegypti, rested in pesticide-free containers.

From this finding, mosquitoes pre-exposed to non-lethal doses of pesticides can learn to avoid these pesticides and, as a result, seek out safer food sources and rest areas and survive. , It is suggested that it is thought to have propagated.

 
* This article is reprinted from "Nature Japan Featured Highlights".
Reprinted from: "Biology: Mosquitoes once exposed to non-lethal doses of pesticides learn to avoid pesticides'