Mechanisms of resistance to insecticides targeting RDL GABA receptors in planthoppers

• Published in: Neurotoxicology (Park Forest South) Vol. 60; pp. 293 - 298
• Main Author: Nakao, Toshifumi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.05.2017; Elsevier BV
• Subjects: Agrochemicals; Animals; Cross-resistance; Cyclodiene resistance; Dieldrin; Endosulfan; Fipronil; Fipronil resistance; gamma-Aminobutyric Acid - pharmacology; Hemiptera; Inhibitory Concentration 50; Insecticide Resistance; Insecticides; Insecticides - toxicity; Insects; Lindane; Low level; Mutation; Pest control; Pesticides; Pests; Pyrazoles - toxicity; RDL GABA receptor; Receptors; Receptors, GABA - genetics; Receptors, GABA - physiology; Resistance to control; γ-Aminobutyric acid receptors; Cyclodiene resistance; Fipronil resistance; RDL GABA receptor
• ISSN: 0161-813X; 1872-9711
• DOI: 10.1016/j.neuro.2016.03.009

•A2′S/G mutations in RDL GABA receptor confer cyclodiene resistance in various pests.•A2′S/G mutations confer low level of cross resistance to fipronil.•A2′N mutation in RDL GABA receptor confers fipronil resistance in planthoppers.•PCR-RFLP assays were developed for detecting fipronil-resistant planthoppers.•There is a need to develop novel insecticides effective against A2′ mutations. Lindane and cyclodienes, such as dieldrin and α-endosulfan, represent the first generation of noncompetitive antagonists (NCAs) against the insect RDL GABA receptor. It has been reported that A2′S and A2′G mutations in the membrane-spanning region M2 of the RDL GABA receptor confer resistance to lindane and cyclodienes. Fipronil is a second-generation NCA, but A2′S and A2′G mutations provide a low level of cross-resistance to fipronil. Moreover, a novel A2′N mutation that confers fipronil resistance was found in M2 of the RDL GABA receptors from fipronil-resistant planthoppers in the heterozygous state. Thus, problems are being caused by a worldwide appearance of cyclodiene-resistant pests. And attention must be paid to development of fipronil-resistant planthoppers, such as Sogatella furcifera and Laodelphax striatellus in Japan.