Environmental Entomology (1981) 10, 676-680

Deifalla H. Osman and William A. Brindley (1981)
Estimating monooxygenase detoxification in field populations: Toxicity and distribution of carbaryl in three species of Labops grassbugs
Environmental Entomology 10 (5), 676-680
Abstract: Carbaryl bioassays were conducted in the field with natural populations of three species of grassbugs (Hemiptera: Miridae). Insecticide-coated vials and a portable incubator were used. Grassbug populations differed in carbaryl LC₅₀ with respect to species, sex, date, and location. Pretreatment of the insects with piperonyl butoxide inhibited the monooxygenase (mixed-function oxidase) system, depriving the insects of a key defense against carbaryl. The differences in synergized and unsynergized LC₅₀ values were used to calculate an estimated 'percent dependency upon monooxygenase detoxification' for the grassbugs. Plotting these values against carbaryl LC₅₀ illustrated hypothetical population differences in tolerance and detoxification potential. These were tested in the laboratory with two species. Males were found to be more susceptible to carbaryl than were the females, with population LC₅₀ values falling as the season progressed. Labops hesperius Uhler was the most tolerant species, with some overlapping values with Labops hirtus Knight. Labops utahensis later was the most susceptible and contained the lowest level of monooxygenase activity.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

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.
	Labops hesperius	Grasses/turf/rangeland	U.S.A. (SW)