Acetylcholinesterase point mutations in European strains of Tetranychus urticae (Acari: Tetranychidae) resistant to organophosphates

Abstract

Four AChE1 mutations were found in resistant strains of T. urticae, and three of them, F331W, G328A and A201S, are possibly involved in resistance to OP and CARB insecticides. Among them, F331W is probably the most important and the most common in T. urticae. It can be easily detected by the diagnostic PCR-RLFP assay developed in this study.

A single nucleotide polymorphism in the acetylcholinesterase gene of the predatory mite Kampimodromus aberrans (Acari: Phytoseiidae) is associated with chlorpyrifos resistance

“…Although reductions in chlorpyrifos susceptibility have been reported in other predatory mites, e.g., T. pyri (Fitzgerald and Solomon, 1999;Cross and Berrie, 1994;Bonafos et al, 2008), little is known about the underlying molecular mechanisms. Among the Acari, high AChE insensitivity to chlorpyrifos was strongly associated to a F331W amino acid substitution in Tetranychus urticae Koch (Acari: Tetranychidae) (Khajehali et al, 2010).…”

Resistance to chlorpyriphos in the predatory mite Kampimodromus aberrans

“…Vidal and Kreiter (1995) found hydrolitic and oxidative mechanisms in T. pyri and emphasized the role of modification in pesticide targets, particularly acetylcholinesterase. Among other mite species, resistance to OPs has been well studied in Tetranychus urticae Koch (van Leeuwen et al 2010), in which a prominent resistance mechanism has also been associated with target site modification (Khajehali et al 2010). Our experiments were based on residual exposure only, whereas in field conditions topical and ingestion exposure may also be involved, leading to higher toxicity values in predatory mites (Pozzebon et al 2011).…”

Riscos Ecotoxicológicos do Metamidofós

“…Estudos demonstram que algumas espécies, como por exemplo, o ácaro (Tetranychus urticae), possuem mutações em genes que codificam a enzima AChE, o que conferem resistência a praguicidas organofosforados (KHAJEHALI et al, 2010;KWON et al, 2010 …”