The Canadian Entomologist (2010) 142, 234-249

L.D. Andreassen, U. Kuhlmann, J.W. Whistlecraft, J.J. Soroka, P.G. Mason, O.O. Akinremi and N.J. Holliday (2010)
Spring emergence of Canadian Delia radicum and synchronization with its natural enemy, Aleochara bilineata
The Canadian Entomologist 142 (3), 234-249
Abstract: To characterize time of spring emergence following post-diapause development, Delia radicum (L.) (Diptera: Anthomyiidae) from Saskatchewan, Manitoba, and southwestern Ontario were collected in fall, maintained over winter at 1 °C, then transferred to higher constant temperatures until adult emergence. At each location there were "early" and "late" phenotypes. Truncated normal models of temperature dependency of development rate were fitted for each phenotype from each location. We provide the first evidence of geographic variation in the criteria separating these phenotypes. Separation criteria and models for early and late phenotypes at the two prairie locations, approximately 700 km apart, were indistinguishable, but differed from those for Ontario. Prairie phenotypes developed more slowly than Ontario phenotypes, and more prairie individuals were of the late phenotype. Poor synchronization of spring emergence could impair predation of D. radicum eggs by adult Aleochara bilineata Gyllenhal (Coleoptera: Staphylinidae). Aleochara bilineata from Manitoba were reared and development rates modelled as for D. radicum. Models of development rates for the two species, when combined with simulated soil temperatures for two prairie locations, suggest that emergence of adult A. bilineata is well synchronized with availability of D. radicum eggs in prairie canola.
(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): Neil J. Holliday, Juliana J. Soroka, Peter G. Mason, Ulrich Kuhlmann

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

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Delia radicum		Canada (east)
	Delia radicum		Canada (west)
Aleochara bilineata (parasitoid)	Delia radicum		Canada (west)