Work

New mutations of acetylcholinesterase in Bactrocera dorsalis populations across southern China and impact on resistance to organophosphate

Year: 2025

Type: article

Abstract: Bactrocera dorsalis , a highly destructive and invasive fruit pest, has spread from the south to the north, significantly increasing the risk to agricultural and horticultural crops worldwide. Currently, chemical insecticides remain the primary method of controlling B. dorsalis . Chlorpyrifos, an organophosphate insecticide, has become the main alternative in China following the 2008 ban on five highly toxic organophosphates. However, the current status of resistance and its underlying mechanisms remain largely unclear. The study monitored the resistance levels of five field populations in China, revealing moderate resistance to chlorpyrifos (resistance ratios 7.57–17.06-fold). Six mutations (I214V, G420A, G488S, Q643R, H645L and T659A) in the target acetylcholinesterase 2 (AChE2) of chlorpyrifos were firstly identified, with high heterogeneity among field populations. This significant association were found between the G420A mutation frequency and chlorpyrifos resistance, evidence in both the individual survival rates and the population resistance levels. In vitro expression of ten AChE2 variation showed G420A conferred greater reduced sensitivity to chlopyrifos than other mutations, while H645L and T659A combined with Q643R increased sensitivity. Most variants retained substantial substrate hydrolysis activity. We compared twelve mutations in AChE2 reported in insects and discussed their implications. These provides critical insights into B. dorsalis control strategies and the development of more effective insecticides targeting AChE2 in insects. • Filed populations of Bactrocera dorsalis in China exhibit resistant to chlorpyrifos. • Six mutations in BdAChE2 were firstly identified, showing high heterogeneity. • G420A frequency and chlorpyrifos resistance was significant association. • G420A conferred greater reduced sensitivity to chlopyrifos than other mutations • Eight AChE2 mutations showed no codon bias and consistent codon usage across insects

Source: Ecotoxicology and Environmental Safety

DOI: 10.1016/j.ecoenv.2025.118189

Authors: Yinjun Fan, Xinyi Dong, Dan Yang, Yu Qin, Xueping Hu, Hongxu Zhou

Institutions: Qingdao Agricultural University, Shandong University

Language: English

Topic: Insect Resistance and Genetics

Subfield: Molecular Biology

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $3,650