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THE EFFECT OF HOST DENSITY ON EGG DISTRIBUTION BY THE SOLITARY PARASITOID APHIDIUS NIGRIPES (HYMENOPTERA: APHIDIIDAE)1

Published online by Cambridge University Press:  31 May 2012

Conrad Cloutier
Conrad Cloutier
Affiliation:
Département de Biologie, Université Laval, Ste-Foy, Québec G1K 7P4
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Abstract

Egg distribution by the solitary parasitoid Aphidius nigripes was studied experimentally at 14 densities of the host aphid, Macrosiphum euphorbiae. The number of hosts parasitized increased with host density, the functional response being of Holling's type II. However the average number of eggs/female was not significantly affected by host density, and consequently superparasitism increased with decreasing host density. When egg distributions were tested against random models, higher than predicted numbers of both unparasitized and superparasitized hosts were observed at all densities tested. Further analysis assuming random search suggested that female A. nigripes tend to deposit several eggs per host while experiencing a low rate of encounter with hosts. The ecological significance of this behaviour is examined.

Résumé

La distribution des oeufs a été étudiée expérimentalement chez le parasitoide Aphidius nigripes à 14 densités de son hôte aphidien, Macrosiphum euphorbiae. Le nombre d'hôtes parasités a augmenté avec la densité d'hôtes, la réponse fonctionnelle étant du type II de Holling. Cependant, le nombre d'oeufs/femelle n'a pas été affecté significativement par la densité d'hôtes et en conséquence, le superparastisme a augmenté avec la diminution de la densité d'hôtes. Une comparaison des distributions de fréquence du nombre d'oeufs/hôte avec des modèles aléatoires a révélé que les nombres d'hôtes non parasités et superparasités étaient plus élevés que prédit à toutes les densités testées. L'analyse poursuivie en présumant que le parasitoide avait un comportement de recherche aléatoire a révélé une tendance claire de la femelle A. nigripes à déposer plusieurs oeufs par hôte lorsqu'elle rencontre des hôtes avec une fréquence réduite. La signification écologique de ce comportement est abordée dans la discussion.

Type
Articles
Information
The Canadian Entomologist , Volume 116 , Issue 6 , June 1984 , pp. 805 - 811
Copyright
Copyright © Entomological Society of Canada 1984

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References

Alphen, J. J. M. van and Nell, H. W.. 1982. Superparasitism and host discrimination by Asobara tabida Nees (Braconidae: Alysiina), a larval parasitoid of Drosophilidae. Neth. J. Zool. 32: 232–260.CrossRefGoogle Scholar
Bakker, K., Eijsackers, H. J. P.van Lenteren, J. C., and Meelis, E.. 1972. Some models describing the distribution of eggs of the parasite Pseudocoila bochei (Hym., Cynip.) over its hosts, larvae of Drosophila melanogaster. Oecologia (Berlin) 10: 29–57.Google Scholar
Cloutier, C., McNeil, J., and Régnière, J.. 1981. Fecundity, longevity, and sex ratio of Aphidius nigripes (Hymenoptera: Aphidiidae) parasitizing different stages of its host, Macrosiphum euphorbiae (Homoptera: Aphididae). Can. Ent. 113: 193–198.CrossRefGoogle Scholar
Griffiths, D. 1977. Avoidance-modified generalized distributions and their application to studies of superparasitism. Biometrics 33: 103–112.CrossRefGoogle ScholarPubMed
Hamilton, W. D. 1967. Extraordinary sex ratios. Science 156: 477–488.CrossRefGoogle ScholarPubMed
Hassell, M. P. 1978. The dynamics of arthropod predator-prey systems. Princeton University Press, Princeton. 237 pp.Google ScholarPubMed
Holling, C. S. 1959. Some characteristics of simple types of predation and parasitism. Can. Ent. 91: 385–398.CrossRefGoogle Scholar
Laraichi, M. 1978. Le phénomène du superparasitisme chez les parasites oophages des punaises du blé. Entomophaga 23: 121–128.CrossRefGoogle Scholar
Lenteren, J. C. van. 1981. Host discrimination by parasitoids. pp. 153–179in Nordlund, D. A., Jones, R. L., and Lewis, W. J. (Eds.), Semiochemicals, Their Role in Pest Control. Wiley, N.Y.Google Scholar
Mackauer, M. 1983. Quantitative assessment of Aphidius smithi (Hymenoptera: Aphididae): Fecundity, intrinsic rate of increase, and functional response. Can. Ent. 115: 399–415.CrossRefGoogle Scholar
Pollard, J. H. 1977. A Handbook of Numerical and Statistical Techniques. Cambridge University Press, London.CrossRefGoogle Scholar
Read, D. P., Feeny, P. P., and Root, R. B. 1970. Habitat selection by the aphid parasite Diaeretiella rapae (Hymenoptera: Braconidae) and hyperparasite Charips brassicae (Hymenoptera: Cynipidae). Can. Ent. 102: 1567–1578.CrossRefGoogle Scholar
Rogers, D. 1975. A model for avoidance of superparasitism by solitary insect parasitoids. J. Anim. Ecol. 44: 623–638.CrossRefGoogle Scholar
Salt, G. 1935. Experimental studies in insect parasitism III. Host selection. Proc. Roy. Soc. (London) B 117: 413–435.Google Scholar
Salt, G. 1961. Competition among insect parasitoids. Symp. Soc. exp. Biol. 15: 96–144.Google Scholar
Schuster, D. J. and Starks, K. J.. 1974. Response of Lysiphlebus testaceipes in an olfactometer to a host and a non-host insect and to plants. Environ. Ent. 3: 1034–1035.CrossRefGoogle Scholar
Shands, W. A., Simpson, G. W., and Gordon, C. C.. 1972. Survey of internal parasites of potato-infesting aphids in Northeastern Maine, 1963 through 1969. University of Maine Life Sciences and Agriculture Experiment Station, Tech. Bull. 60. 15 pp.Google Scholar
Shands, W. A., Simpson, G. W., Muesebeck, C. F. W., and Wave, H. E.. 1965. Parasites of potato-infesting aphids in northeastern Maine. Maine Agricultural Experiment Station, Tech. Bull. 19. 77 pp.Google Scholar
Singh, R. and Sinha, T. B.. 1982. Factors responsible for the superparasitic ability of the parasitoid wasp Trioxys indicus (Hymenoptera: Aphidiidae). Ent. Gener. 7: 295–300.Google Scholar
Sokal, R. R. and Rohlf, F. J.. 1981. Biometry, 2nd ed. W.H. Freeman, San Francisco.Google Scholar
Vinson, S. B. and Iwantsch, G. F.. 1980. Host suitability for insect parasitoids. A. Rev. Ent 25: 397–419.CrossRefGoogle Scholar