Hostname: page-component-cd9895bd7-mkpzs Total loading time: 0 Render date: 2024-12-26T04:40:23.786Z Has data issue: false hasContentIssue false
  • English
  • Français

THE DIAPAUSE RESPONSE TO PHOTOPERIOD IN ONTARIO POPULATIONS OF COTESIA MELANOSCELA (RATZEBURG) (HYMENOPTERA: BRACONIDAE)

Published online by Cambridge University Press:  31 May 2012

V.G. Nealis ,
D. Oliver  and
D. Tchir
V.G. Nealis
Affiliation:
Canadian Forest Service-Sault Ste. Marie, PO Box 490, Sault Ste. Marie,Ontario, Canada P6A 5M7
D. Oliver
Affiliation:
Canadian Forest Service-Sault Ste. Marie, PO Box 490, Sault Ste. Marie,Ontario, Canada P6A 5M7
D. Tchir
Affiliation:
Canadian Forest Service-Sault Ste. Marie, PO Box 490, Sault Ste. Marie,Ontario, Canada P6A 5M7
Get access Rights & Permissions [Opens in a new window]

Abstract

The diapause response to photoperiod in Ontario populations of Cotesia melanoscela, an introduced parasitoid of the gypsy moth, Lymantria dispar (L.) (Lepidoptera: Lymantriidae), was investigated under a series of stationary photoperiods and constant temperature. When the parasitic larval stages of C. melanoscela were exposed to different photoperiods, the insect exhibited a typical long-day response: long days (greater than 18 h) promoted continuous development whereas short days (less than 16 h) resulted in diapause in the cocooned prepupal stage. Within the region of the critical photoperiod (16–18 h) the diapause response was associated with larval development time. Individuals that developed more slowly were more likely to enter diapause. Cotesia melanoscela was sensitive to photoperiod throughout its entire larval period. These individual responses are used to interpret patterns of seasonality of the parasitoid in Ontario and to compare with published information from populations of C. melanoscela in New England.

Résumé

L’influence de la photopériode sur la diapause au sein des populations ontariennes de Cotesia melanoscela, un parasotoïde introduit de la Spongieuse, Lymantria dispar (L.) (Lepidoptera : Lymantriidae), a fait l’objet d’une étude dans une série de conditions constantes de photopériode et de température. Lorsque les larves de C. melanoscela sont exposées à différentes photopériodes au cours de leurs stades parasites, l’insecte réagit comme il le fait dans des conditions de jours longs : les jours longs (plus de 18 h) favorisent le développement continu, alors que les jours courts (moins de 16 h) déclenchent le diapause des larves de stade pré-nymphe dans leur cocon. Près du seuil critique (photopériode de 16 à 18 h), le déclenchement de la diapause est relié à la vitesse du développement larvaire : les individus à développement lent sont plus susceptibles d’entrer en diapause. Cotesia melanoscela est sensible à la photopériode durant toute la durée de son développement larvaire. Ces variations individuelles sont utilisées ici pour interpréter les aspects saisonniers de la biologie du parasitoïde en Ontario et elles sont comparées aux données publiées sur les populations de C. melanoscela de Nouvelle-Angleterre.

[Traduit par la Rédaction]

Type
Articles
Information
The Canadian Entomologist , Volume 128 , Issue 1 , February 1996 , pp. 41 - 46
Copyright
Copyright © Entomological Society of Canada 1996

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

Beck, S.D. 1980. Insect Photoperiodism, 2nd ed. Academic Press, New York, NY. 387 pp.Google Scholar
Bourchier, R.S., and Nealis, V.G.. 1992. Patterns of hyperparasitism of Cotesia melanoscela (Hymenoptera: Braconidae) in southern Ontario. Environmental Entomology 21: 907–912.CrossRefGoogle Scholar
Burgess, A.F., and Crossman, S.S.. 1929. Imported Insect Enemies of the Gipsy Moth and the Brown-tail Moth. USDA Technical Bulletin 86: 147 pp.Google Scholar
Feinberg, S.F. 1980. The Analysis of Cross-Classified Data, 2nd ed. MIT Press, Cambridge, MA. 198 pp.Google Scholar
Hoy, M.A. 1975. Hybridization of strains of the gypsy moth parasitoid, Apanteles melanoscelus, and its influence on diapause. Annals of the Entomological Society of America 68: 261–264.CrossRefGoogle Scholar
Nealis, V.G. 1985. Diapause and the seasonal ecology of the introduced parasite, Cotesia (Apanteles) rubecula (Hymenoptera: Branconidae). The Canadian Entomologist 117: 333–342.CrossRefGoogle Scholar
ODell, T.M., Butt, C.A., and Bridgeforth, A.W.. 1985. Lymantria dispar. pp. 355–367 in Singh, P., and Moore, R.F. (Eds.), Handbook of Insect Rearing, Vol. II. Elsevier, Amsterdam. 514 pp.Google Scholar
Saunders, D.S. 1982. Insect Clock, 2nd ed. Pergamon Press, Oxford. 409 pp.Google Scholar
Statistical Sciences. 1994. S-PLUS for Windows Version 3.2 Supplement. Seattle, WA.Google Scholar
Weseloh, R.M. 1973. Termination and induction of diapause in the gypsy moth larval parasitoid, Apanteles melanoscelus. Journal of Insect Physiology 19: 2025–2033.CrossRefGoogle Scholar
Weseloh, R.M. 1976. Reduced effectiveness of the gypsy moth parasite, Apanteles melanoscelus, in Connecticut due to poor seasonal synchrony with its host. Environmental Entomology 5: 743–746.CrossRefGoogle Scholar