Journal of Applied Entomology (2004) 128, 233-239

É. Lucas, S. Giroux, S. Demougeot, R.-M. Duchesne and D. Coderre (2004)
Compatibility of a natural enemy, Coleomegilla maculata lengi (Col., Coccinellidae) and four insecticides used against the Colorado potato beetle (Col., Chrysomelidae)
Journal of Applied Entomology 128 (3), 233-239
Abstract: The toxicity of four insecticides used to control the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae), imidacloprid (Admire^®), cryolite (Kryocide^®), cyromazine (Trigard^®), and Bacillus thuringiensis var. tenebrionis (Novodor^®), to one of its natural enemies, the 12-spotted lady beetle, Coleomegilla maculata lengi Timberlake (Coleoptera: Coccinellidae) was determined in the laboratory. Toxicity assays against C. maculata adults and larvae consisted of (1) topical applications and (2) exposures to treated foliage and prey, using concentrations up to 10 times the manufacturer's recommendations. Over a 6-day period, cyromazine (insect growth regulator) and B. t. var. tenebrionis (microbial insecticide) had no lethal effects on first and third instars C. maculata. For both larval and adult stages, cryolite (inorganic insecticide) caused very low predator mortality when topically applied and moderate mortality when ingested through contaminated eggs of Colorado potato beetles. Imidacloprid (systemic organic insecticide) was highly toxic to adult and larval C. maculata. Its estimated LD₅₀ at 6 days following treatment, corresponded to 0.02-0.09 times the recommended field concentration, depending on the developmental stage and mode of contamination. These results indicate that integrated pest management programmes for Colorado potato beetles using imidacloprid or, to a lesser degree, cryolite, would be detrimental to C. maculata. Cyromazine and B. t. var. tenebrionis seem to present a better compatibility with the protection of C. maculata populations.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Éric Lucas, Daniel Coderre

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
health/environmental effects of pesticides
Research topic(s) for beneficials or antagonists:
environment/habitat manipulation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Leptinotarsa decemlineata
Coleomegilla maculata (predator)	Leptinotarsa decemlineata
Bacillus thuringiensis var. tenebrionis (entomopathogen)	Leptinotarsa decemlineata