Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-25T07:31:04.040Z Has data issue: false hasContentIssue false
  • English
  • Français

DISPLACEMENT OF BATHYPLECTES CURCULIONIS (THOMS.) (HYMENOPTERA: ICHNEUMONIDAE) BY B. ANURUS (THOMS.) IN EASTERN ONTARIO POPULATIONS OF THE ALFALFA WEEVIL, HYPERA POSTICA (GYLL.) (COLEOPTERA: CURCULIONIDAE)

Published online by Cambridge University Press:  31 May 2012

D.G. Harcourt
D.G. Harcourt
Affiliation:
Plant Research Centre, Agriculture Canada, Ottawa, Ontario, Canada K1A 0C6
Get access Rights & Permissions [Opens in a new window]

Abstract

Bathyplectes anurus (Thoms.) has displaced B. curculionis (Thorns.) as the main larval parasitoid in populations of the alfalfa weevil, Hypera postica (Gyll.), in eastern Ontario. Following its belated spread to the Bay of Quinte dairy belt, it used a combination of r and K strategies to assert its superiority: a greater reproductive capacity, more rapid search and handling, and more aggressive behaviour. Also, it is not subject to encapsulation by the host and reduces direct competition with the entomopafhogenic fungus Zoophthora phytonomi (Arthur) by laying its eggs in older hosts that have a greater probability of escaping death from disease. Taken together, these factors have enabled it to perform better than B. curculionis and to displace it in the host–parasitoid community. Moreover, it may have the potential to stabilize weevil populations during years when the fungus is enzootic.

Résumé

Bathyplectes anurus (Thoms.) a déplacé B. curculionis (Thoms.) comme parasitoïde larvaire principal aux populations du charançon postiche de la lucerne, Hypera postica (Gyll.), dans l’est de l’Ontario. Suite à sa diffusion tardive à la zone laitière de la Baie de Quinte, il a utilisé une combinaison de stratégies de r et K pour faire valoir sa supériorité : une capacité réproductrice plus grande, la recherche et le traitement plus rapide, et un comportement plus aggressif. Aussi, il n’est pas assujetti d’être enclos par l’hôte et la compétition directe avec le champignon entomopathogénique Zoophthora phytonomi (Arthur) est réduite à cause que la ponte dans les hôtes âgés permet aux oeufs une plus grande possibilité d’échapper à la mort occasionnée par la maladie. Pris dans l’ensemble, ces éléments ont donné le pouvoir de mieux s’acquitter que B. curculionis et de le déplacer dans la communauté hôte–parasitoïde. De plus, il pourrait avoir le potentiel pour stabiliser les populations de charançon pendant les années où le champignon est enzootique.

Type
Articles
Information
The Canadian Entomologist , Volume 122 , Issue 4 , August 1990 , pp. 641 - 645
Copyright
Copyright © Entomological Society of Canada 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bartell, D.P. 1973. Biology of immature forms of Bathyplectes anurus (Thomson), and Bathyplectes curculionis (Thomson), and their effect on the growth, development and tissues of their host, Hypera postica (Gyllenhal). Ph.D. thesis, University of Kentucky, Lexington, KY.Google Scholar
Brunson, M.H., and Coles, L.W.. 1968. The introduction, release, and recovery of parasites of the alfalfa weevil in eastern United States. U.S.D.A. Prod. Res. Rep. 101. 12 pp.Google Scholar
Day, W.H. 1983. Incidence of nonfunctional ovaries in Bathyplectes anurus and B. curculionis (Hymenoptera: Ichneumonidae), parasites of the alfalfa weevil (Coleoptera: Curculionidae) in the northeastern United States. Environ. Ent. 12: 1125–1128.CrossRefGoogle Scholar
Dowell, R.V., and Horn, D.J.. 1977. Adaptative strategies of larval parasitoids of the alfalfa weevil (Coleoptera: Curculionidae). Can. Ent. 109: 641–648.CrossRefGoogle Scholar
Dysart, R.J., and Day, W.H.. 1976. Release and recovery of introduced parasites of the alfalfa weevil in eastern North America. U.S.D.A. Prod. Res. Rep. 167. 61 pp.Google Scholar
Force, D.G. 1972. r- and K-strategists in endemic host-parasitoid communities. Bull. ent. Soc. Am. 18: 135–137.Google Scholar
Harcourt, D.G. 1985. Resurgence of the alfalfa weevil: analysis of the outbreak. Proc. 22nd N.E. Reg. Alfalfa, Corn, and Small Grains Insect Conf. pp. 9–20.Google Scholar
Harcourt, D.G., and Guppy, J.C.. 1975. Population and mortality assessment during the cocoon stage of the alfalfa weevil, Hypera postica (Coleoptera: Curculionidae). Environ. Ent. 107: 1275–1280.Google Scholar
Harcourt, D.G., and Guppy, J.C.. 1990. Numerical analysis of an outbreak of the alfalfa weevil (Coleoptera: Curculionidae) in eastern Ontario. Environ. Ent. In press.Google Scholar
Harcourt, D.G., Guppy, J.C., and Binns, M.R.. 1977. The analysis of intrageneration change in eastern Ontario populations of the alfalfa weevil, Hypera postica (Coleoptera: Curculionidae). Can. Ent. 109: 1521–1534.CrossRefGoogle Scholar
Harcourt, D.G., Guppy, J.C., and Binns, M.R.. 1984. Analysis of numerical change in subeconomic populations of the alfalfa weevil, Hypera postica (Coleoptera: Curculionidae), in eastern Ontario. Environ. Ent. 13: 1627–1633.CrossRefGoogle Scholar
Harcourt, D.G., Guppy, J.C., and Tyrrell, D.. 1990. Phenology of the fungal pathogen Zoophthora phytonomi (Arthur) in southern Ontario populations of the alfalfa weevil, Hypera postica (Coleoptera: Curculionidae). Environ. Ent. In press.Google Scholar
Price, P.W. 1973. Parasitoid strategies and community organization. Environ. Ent. 2: 623–626.CrossRefGoogle Scholar
Puttler, B. 1967. Interrelationship of Hypera postica (Coleoptera: Curculionidae) and Bathyplectes curculionis (Hymenoptera: Ichneumonidae) in the eastern United States with particular reference to encapsulation of the parasite eggs by the weevil larvae. Ann. ent. Soc. Am. 60: 1031–1037.CrossRefGoogle Scholar
Williamson, G.D. 1971. Insect liberations in Canada. 1970. Parasites and predators. Can. Agric. Lib. Bull. 34. 16 pp.Google Scholar
Yeargan, K.V., and Pass, B.C.. 1978. Description and incidence of nonfunctional ovaries in Bathyplectes curculionis (Hymenoptera: Ichneumonidae). J. Kansas ent. Soc. 51: 213–217.Google Scholar