Isolation and Characterization of an Insecticide-Resistance-Associated Esterase in the Tobacco Budworm Heliothis virescens (F.)

Overexpressed esterases in a fenvalerate resistant strain of the cotton bollworm, Helicoverpa armigera

“…The association of multiple CCEs in our study is consistent with previous associations of pyrethroid resistance with elevated staining intensities of multiple esterase isozymes in this species (Gunning et al, 1996(Gunning et al, , 1998(Gunning et al, , 1999Campbell, 2001) and its relatives, Helicoverpa punctigera and Heliothis virescens (Dowd et al, 1987;Goh et al, 1995;Gunning et al, 1997). Interestingly, the same pattern is also evident in two species of Spodoptera that have evolved metabolic resistance to synthetic pyrethroids (Farnsworth et al, 2010, for a review).…”

“…or whether some at least are simply incidentally associated as a result the co-occurrence in regulatory networks or linkage disequilibrium relationships. Also noteworthy here are the associations between esterase isozyme intensities and metabolic resistances to other classes of insecticides, including organophosphates and carbamates, which have been reported among various heliothine pests, including H. armigera (Goh et al, 1995;Srinivas et al, 2006;Zhao et al, 1996;Harold and Ottea, 2000;Campbell, 2001;Farnsworth et al, 2010). Several of the H. armigera isozymes implicated in these resistances have R m values which overlap those associated with pyrethroid resistance .…”

Carboxylesterases in the Metabolism and Toxicity of Pesticides

“…Indeed, structurally related enzymes have evolved in bacteria that catalyze their hydrolysis at relatively fast rates (Pohlenz et al 1992). There is, however, a notable instance in which metabolic carbamate (thiodicarb) resistance has been clearly linked to an overexpressed CarbE in the moth Heliothis virescens (Goh et al 1995). This enzyme was also shown to be immunoreactive to specific antibodies to, and share sequence similarity to, the E4 esterase from M. persicae, suggesting it is likely to be related.…”

Characterization of esterases associated with profenofos resistance in the tobacco budworm,Heliothis virescens (F.)

“…In previous studies, elevated activities of ESTs toward permethrin, α-NA (Dowd et al, 1987) and methyl parathion (Konno et al, 1989(Konno et al, , 1990 have been documented in larvae from laboratory strains of OP-resistant H. virescens. More recently, EST activities toward α-NA from mass homogenates of thiodicarb-selected H. virescens were suggested to be responsible for cross-resistance among carbamate, OP, and pyrethroid insecticides (Goh et al, 1995;Zhao et al, 1996). In the present study, a high level of resistance to cypermethrin (17-fold at the LD 50 ) was measured in OPR larvae (data not shown), suggesting that metabolic mechanisms expressed in this strain may confer cross-resistance between cypermethrin and profenofos.…”