Environmental Entomology (1996) 25, 1376-1382

Daniel Cormier, A.B. Stevenson and Guy Boivin (1996)
Seasonal ecology and geographical distribution of Anaphes listronoti and A. victus (Hymenoptera: Mymaridae), egg parasitoids of the carrot weevil (Coleoptera: Curculionidae) in central Ontario
Environmental Entomology 25 (6), 1376-1382
Abstract: Field surveys were conducted during 3 yr in the Holland Marsh and district marshes to evaluate egg parasitism of the carrot weevil, Listronotus oregonensis (LeConte). Anaphes listronoti Huber was the dominant species in Ontario and was widely distributed in the sampled area. In commercial fields, up to 33% of the carrot weevil eggs were parasitized by Anaphes spp. In an untreated plot, parasitism averaged 68% and reached 94% in high density of carrot weevil eggs. Spring emergence of the parasitoids occurred from the end of April to mid-May, at which time the carrot weevil had begun its oviposition period in wild plants. Parasitoids had to complete between 1.6 and 2.3 generations outside the carrot fields before the appearance of carrot weevil eggs in plants. Parasitized eggs were observed in carrot fields from the beginning of the carrot weevil oviposition until September.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Guy Boivin

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
surveys/distribution/isolation
population dynamics/epizootiology

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Listronotus oregonensis	Carrot (Daucus carota)	Canada (east)
Anaphes listronoti (parasitoid)	Listronotus oregonensis	Carrot (Daucus carota)	Canada (east)
Anaphes victus (parasitoid)	Listronotus oregonensis	Carrot (Daucus carota)	Canada (east)