Slow resistance evolution to neonicotinoids in field populations of wheat aphids revealed by insecticide resistance monitoring in China.

BACKGROUND: The wheat aphids, Rhopalosiphum padi and Sitobion miscanthi, are serious agricultural insect pests of many crops. Neonicotinoid insecticides are commonly used as alternatives to organophosphate and pyrethroid insecticides for controlling wheat aphids. RESULTS: Long-term monitoring of resistance to imidacloprid and acetamiprid in R. padi and S. miscanthi was carried out between 2007 and 2019. For this study, 344 specimens of the two wheat aphids were collected from field populations found in the main wheat production areas in China, from 2007 to 2019. In R. padi, the fluctuation in resistance was 14.7 times for imidacloprid and 1.4 times for acetamiprid; in S. miscanthi, it was 9.7 times for imidacloprid and 6.5 times for acetamiprid. CONCLUSION: Our results demonstrated that both R. padi and S. miscanthi tended to have higher resistance to imidacloprid compared with acetamiprid. However, it is difficult for wheat aphids to develop a high level of neonicotinoid resistance given the pest control practices used in China. These results should be useful for the biorational application and resistance management of neonicotinoid insecticides. © 2021 Society of Chemical Industry.