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SEASONAL DEVELOPMENT, BEHAVIOR, AND HOST SYNCHRONY OF DACNUSA DRYAS (NIXON) (HYMENOPTERA: BRACONIDAE) PARASITIZING THE ALFALFA BLOTCH LEAFMINER, AGROMYZA FRONTELLA (RONDANI) (DIPTERA: AGROMYZIDAE)1

Published online by Cambridge University Press:  31 May 2012

J.C. Guppy
Affiliation:
Plant Research Centre, Agriculture Canada, Ottawa, Ontario, Canada KIA OC6
F. Meloche
Affiliation:
Plant Research Centre, Agriculture Canada, Ottawa, Ontario, Canada KIA OC6
D.G. Harcourt
Affiliation:
Plant Research Centre, Agriculture Canada, Ottawa, Ontario, Canada KIA OC6

Abstract

Studies in eastern Ontario showed that the exotic parasite Dacnusa dryas (Nixon) typically has three generations a year that correspond seasonally to those of its host, the alfalfa blotch leafminer, Agromyza frontella (Rondani). The mature larvae of the third generation enter diapause in September and resume development in the spring. The egg – first instar interval, which occurs within the actively feeding leafminer, developed at rates similar to those of the host larva. The remaining two instars and the pupa, which occur within the host puparium, developed at rates similar to those of the host pupa; in the two non-diapausing generations, the durations of these stages decreased with rise in temperature from 13 to 23 °C. Coincidence of wasp flight and hatch of leafminer eggs was high in all three generations. This host–parasite synchrony results mainly from a sequence of three events during their life cycles: lack of development of the parasite beyond the first instar within the host larva, a temperature-dependent rate of development of the subsequent stages which is similar to that of the host pupa, and different overwintering strategies which result in the parasite emerging later than its host to sustain the relationship. Behavior of the parasite is described in relation to host detection, egg deposition, and reproduction.

Résumé

Des études effectuées dans l’est de l’Ontario ont révélé que le parasite exotique Dacnusa dryas (Nixon) produit typiquement trois générations par année qui correspondent de façon saisonnière à celles de son hôte, l’agromyze de la luzerne Agromyza frontella (Rondani). Les larves matures de la troisième génération entrent en diapause en septembre et reprennent leur développement le printemps suivant. L’intervalle entre l’oeuf et le premier stade larvaire qui se déroule dans l’agromyze en pleine activité d’alimentation, se fait au même rythme que celui des larves hôtes. Les deux autres stades larvaires et la pupe qui se rencontrent dans le puparium de l’hôte, se développent au même rythme que ceux de la pupe hôte; dans les deux générations qui n’entrent pas en diapause, la durée de ces stades diminue avec l’élévation de température de 13 à 23 °C. La coïncidence du vol des guêpes et de l’éclosion des oeufs de l’agromyze est élevée pour les trois générations. Ce synchronisme hôte–parasite résulte principalement d’une succession de trois événements au cours de leurs cycles biologiques : l’absence de développement du parasite au-delà du premier stade larvaire de la larve hôte, un taux de développement des stades subséquents tributaire de la température (semblable à celui de la pupe hôte) et diverses stratégies d’hivernage qui font en sorte que le parasite émerge plus tard que son hôte pour maintenir la relation. Les auteurs décrivent le comportement du parasite pour ce qui est de la détection de l’hôte, de l’oviposition et de la reproduction.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1988

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References

Baskerville, G.L., and Emin, P.. 1969. Rapid estimation of heat accumulation from maximum and minimum temperatures. Ecology 50: 514517.CrossRefGoogle Scholar
Boyce, T.M. 1985. Phenological synchrony of the alfalfa blotch leafminer (Agromyza frontella, Diptera: Agromyzidae) and its biological control agent, Dacnusa dryas (Hymenoptera: Braconidae): a model for use in integrated pest management. M.S. thesis, Cornell University, Ithaca, NY. × + 100 pp.Google Scholar
Drea, J.J. Jr., and Hendrickson, R.M. Jr., 1986. Analysis of a successful classical biological control project: the alfalfa blotch leafminer (Diptera: Agromyzidae) in the Northeastern United States. Environ. Ent. 15: 448455.CrossRefGoogle Scholar
Guppy, J.C. 1981. Bionomics of the alfalfa blotch leafminer, Agromyza frontella (Diptera: Agromyzidae) in eastern Ontario. Can. Ent. 113: 593600.Google Scholar
Guppy, J.C., Harcourt, D.G., Guibord, M. O'c., and Thompson, L.S.. 1984. Agromyza frontella (Rondani), alfalfa blotch leafminer (Diptera: Agromyzidae). pp. 1113in Kelleher, J.S., and Hulme, M.A. (Eds.), Biological Control Programme against Insects and Weeds in Canada 1969–80. Commonwealth Agricultural Bureaux, Slough, England.Google Scholar
Guppy, J.C., and Meloche, F.. 1987. Life history and description of the immature stages of Dacnusa dryas (Nixon) (Hymenoptera: Braconidae), a European parasite of the alfalfa blotch leafminer (Diptera: Agromyzidae) in eastern Canada. Can. Ent. 119: 281285.CrossRefGoogle Scholar
Harcourt, D.G., and Binns, M.R.. 1980 a. A sampling system for estimating egg and larval populations of Agromyza frontella (Rond.) (Diptera: Agromyzidae) in alfalfa. Can. Ent. 112: 375385.CrossRefGoogle Scholar
Harcourt, D.G., and Binns, M.R.. 1980 b. Sampling techniques for the soil-borne stages of Agromyza fontella (Diptera: Agromyzidae). Great Lakes Ent. 13: 159164.Google Scholar
Harcourt, D.G., Guppy, J.C., and Ellis, C.R.. 1986. Establishment and spread o Dcnusa dryas (Hymenoptera: Braconidae), an exotic parasite of the alfalfa blotch leafminer in Ontario. ent. Soc. Ont. 117: 2933.Google Scholar
Harcourt, D.G., Guppy, J.C., and Meloche, F.. 1988. Population dynamics of the alfalfa blotch leafminer, Agromyza frontella (Diptera: Agromyzidae), in eastern Ontario: impact of the exotic parasite, Dacnusa dryas (Hymenoptera: Braconidae). Environ. Ent. In press.Google Scholar
Harcourt, D.G., Yee, J.M., and Guppy, J.C.. 1983. Two models for predicting the seasonal occurrence of Agromyza frontella (Diptera: Agromyzidae) in eastern Ontario. Environ. Ent. 12: 14551458.CrossRefGoogle Scholar
Hendrickson, R.M. Jr., and Plummer, J.A.. 1983. Biological control of alfalfa blotch leafminer (Diptera: Agromyzidae) in Delaware. J. econ. Ent. 76: 757761.Google Scholar
Sharpe, P.J.H., and DeMichele, D.W.. 1977. Reaction kinetics of poikilotherm development. J. Theor. Biol. 64: 649670.Google Scholar
Snedecor, G.W., and Cochran, W.G.. 1980. Statistical Methods, 7th ed. Iowa State Univ. Press, Ames, IA. xvi + 507 pp.Google Scholar
Wagner, T.L., Wu, H., Sharpe, P.J.H., Schoolfield, R.M., and Coulson, R.N.. 1984. Modeling insect development rates: a literature review and application of a biophysical model. Forum. Ann. ent. Soc. Am. 77: 208255.CrossRefGoogle Scholar