Environmental Entomology (1985) 14, 665-668

Frank L. Filipy, Paul P. Burbutis and Roger W. Fuester (1985)
Biological control of the European wheat stem sawfly in Delaware (Hymenoptera: Cephidae)
Environmental Entomology 14 (6), 665-668
Abstract: Evidence indicates that the introduced parasitoid Collyria coxator (Villers) is providing adequate biological control of Cephus pygmaeus (L.) in Delaware. C. pygmaeus infestations in wheat in 1982 and 1983 averaged ca. 2% while parasitism by C. coxator averaged 44% (range, 0-62%) in 1982 and 52% (range, 27-82%) in 1983. Postharvest (ca. July) sampling of C. pygmaeus larvae along field edges probably provides the best estimates of parasitism rates by C. coxator. There appears to be a strong density-independent parasitoid-host relationship within individual fields, regardless of field size. However, between fields, on an areawide basis, some of the data suggest a density-dependent parasitoid-host relationship.
(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:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
population dynamics/epizootiology
surveys/distribution/isolation

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Cephus pygmeus	Wheat (Triticum)	U.S.A. (NE)
Collyria coxator (parasitoid)	Cephus pygmeus	Wheat (Triticum)	U.S.A. (NE)
Pediobius nigritarsis (parasitoid)	Cephus pygmeus	Wheat (Triticum)	U.S.A. (NE)