Journal of Economic Entomology (1994) 87, 285-292

Alan L. Knight, J.F. Brunner and D. Alston (1994)
Survey of azinphosmethyl resistance in codling moth (Lepidoptera: Tortricidae) in Washington and Utah
Journal of Economic Entomology 87 (2), 285-292
Abstract: A bioassay in which azinphosmethyl was incorporated into the adhesive of a sex pheromone trap was developed to detect resistance in populations of male codling moth, Cydia pomonella (L.). Experiments were done to evaluate the influence of the length of the bioassay, moth body position in the adhesive, moth age, and extremes of temperature and relative humidity (RH) experienced by moths caught in traps in the field. Moth's body position and age for moths <5 d old were not significant factors affecting moth mortality. Exposure to low humidity (45% RH) or low to high temperatures (10-25°C) for up to 12 h did not significantly affect mortality. Forty-eight populations were surveyed in Washington, and three populations were surveyed in Utah during 1991-1992 with a discriminating concentration, 75 µg (AI)/g adhesive; moth mortality was scored after 64 h at 20°C and >85% RH. Populations from crabapple plantings, certified-organic, abandoned, and conventional orchards were sampled. Twenty of 44 populations monitored in 1991 and 12 of 17 populations monitored in 1992 had significant levels of resistance compared with a susceptible laboratory strain based on nonoverlapping 95% CL. All but one of these resistant populations were from current conventional or recently abandoned conventional orchards. Results from the 10 orchards sampled in both years were not significantly different. Resistance in a population collected in 1991 reverted rapidly when removed from exposure to azinphosmethyl and reared on apple in the laboratory.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Alan L. Knight, Jay F. Brunner

Research topic(s) for pests/diseases/weeds:
pesticide resistance of pest

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Cydia pomonella		U.S.A. (SW)
	Cydia pomonella		U.S.A. (NW)