Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-24T11:38:42.576Z Has data issue: false hasContentIssue false

PARASITOIDS OF ENDEMIC AND EPIDEMIC POPULATIONS OF CHORISTONEURA OCCIDENTALIS FREEMAN AND CHORISTONEURA RETINIANA (WALSINGHAM) (LEPIDOPTERA: TORTRICIDAE) IN SOUTHERN OREGON

Published online by Cambridge University Press:  31 May 2012

Willis C. Schaupp Jr.
Affiliation:
Department of Entomological Sciences, University of California, Berkeley, California, USA 94720
W. Jan A. Volney
Affiliation:
Department of Entomological Sciences, University of California, Berkeley, California, USA 94720
William E. Waters
Affiliation:
Department of Entomological Sciences, University of California, Berkeley, California, USA 94720

Abstract

Parasitoid species attacking sparse, endemic populations of Choristoneura occidentalis Freeman and C. retiniana (Walsingham) are reported from 2 years of host collections at seven sites across southern Oregon. Results are compared with rearings from epidemic populations either from the same region or the same plot. Collections were designed to allow quantitative estimation of host density. Most of the parasitoid species present during epidemics across North America were recovered from the endemic and epidemic populations studied. The major difference is that at endemic host densities Glypta fumiferanae (Viereck) (Ichneumonidae) is rare to absent, whereas ichneumonids of the tribe Campoplegini, especially Tranosema (= Diadegma) interruptum (Ashmead), are common. This is the reverse of the situation at epidemic densities and consistent with results reported from eastern North America. It is suggested that the observed shift in the parasite complex with budworm density has the potential for predicting population trends.

Résumé

Les espèces de parasitoïdes qui s’attaquent aux populations endémiques éparses de Choristoneura occidentalis Freeman et de C. retiniana (Walsingham) ont été étudiées après récolte d’hôtes durant 2 ans en sept sites d’échantillonnage répartis dans tout le sud de l’Oregon. Les résultats sont comparés à ceux d’élevages issus de populations épidémiques provenant des mêmes régions ou du même territoire. Les échantillonnages ont été planifiés de façon a permettre l’estimation quantitative de la densité des hôtes. La plupart des espèces de parasitoïdes présentes au cours des grandes infestations en Amérique du Nord ont été récoltées aussi bien chez les populations endémiques que chez les populations épidémiques. La principale différence réside dans le fait qu’aux densités endémiques Glypta fumiferanae (Viereck) (Ichneumonidae) est rare ou absent, alors que les ichneumons de la tribu des Campoplegini, surtout Tranosema (= Diadegma) interruptum (Ashmead), sont communs. Aux densités épidémiques, la situation est renversée et correspond aux résultats signalés dans l’est de l’Amérique du Nord. Nous croyons que ce renversement du complexe de parasites en fonction de la densité des tordeuses pourrait servir à prédire les tendances au sein des populations.

[Traduit par la rédaction]

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1991

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

Askew, R.R., and Shaw, M.R.. 1986. Parasitoid communities: Their size, structure and development. pp. 225–264 in Waage, J., and Greathead, D. (Eds.), Insect Parasitoids. Academic Press, New York, NY. 389 pp.Google Scholar
Blais, J.R. 1959. Incidence of overwintering parasites in post-outbreak populations of the spruce budworm in Gaspé. Can. Dep. Agric. For. Biol. Div. Bi-mon. Prog. Rep. 15(6): 12.Google Scholar
Carlson, R.W. 1979. Ichneumonidae. pp. 315–740 in Krombein, K.V. et al. , (Eds.), Catalogue of Hymenoptera in America North of Mexico, Vol. 1, Symphyta and Apocrita (Parasitica). Smithsonian Inst. Press, Washington, DC. 1198 pp.Google Scholar
Carolin, V.M., and Coulter, W.K.. 1959. The occurrence of insect parasites of Choristoneura fumiferana (Clem.) in Oregon. J. econ. Ent. 52: 550555.CrossRefGoogle Scholar
Carolin, V.M., and Coulter, W.K.. 1972. Sampling populations of western spruce budworm and predicting defoliation on Douglas-fir in eastern Oregon. USDA For. Serv. Res. Pap. PNW-149. 38 pp.Google Scholar
Dasch, C.E. 1988. Ichneumon-flies of America North of Mexico: 10. Subfamily Banchinae, Tribe Glyptini. Mem. Am. ent. Inst. 43. 644 pp.Google Scholar
Dodge, H.R. 1961. Parasitism of spruce budworm by Glypta and Apanteles at different crown heights in Montana. Can. Ent. 93: 222228.CrossRefGoogle Scholar
Dolph, R.E. 1980. Budworm activity in Orgeon and Washington 1947–1979. USDA For. Serv. Rep. R6-FIDM-033. 54 pp.Google Scholar
Ferrell, G.T. 1980. Growth of white firs defoliated by Modoc budworm in northeastern California. USDA For. Serv. Res. Pap. PSW-153. 9 pp.Google Scholar
Furniss, R.L., and Carolin, V.M.. 1977. Western Forest Insects. USDA For. Serv. Misc. Publ. 1339. 654 pp.Google Scholar
Fye, R.E. 1963. The status of the spruce budworm in the Black Sturgeon Lake region of Ontario. Can. Dep. Agric. For. Biol. Div. Bi-mon. Prog. Rep. 19(1): 2.Google Scholar
Harris, J.W.E., and Dawson, A.F.. 1979. Parasitoids of the western spruce budworm, Choristoneura occidentalis (Lepidoptera: Tortricidae), in British Columbia 1977–78. J. ent. Soc. Brit. Columbia 76: 3038.Google Scholar
Lewis, F.B. 1960. Factors affecting assessment of parasitization by Apanteles fumiferanae Vier. and Glypta fumiferanae (Vier.) on spruce budworm larvae. Can. Ent. 92: 881891.CrossRefGoogle Scholar
Mason, W.R.M. 1974. The Apanteles species (Hymenoptera: Braconidae) attacking Lepidoptera in the micro-habitat of the spruce budworm (Lepidoptera: Tortricidae). Can. Ent. 106: 10871102.CrossRefGoogle Scholar
McGugan, B.M., and Blais, J.R.. 1959. Spruce budworm parasite studies in northwestern Ontario. Can. Ent. 91: 758783.CrossRefGoogle Scholar
McKnight, M.E. 1974. Parasitoids of the western spruce budworm in Colorado. Environ. Ent. 3: 186187.CrossRefGoogle Scholar
Miller, C.A., and Renault, T.R.. 1976. Incidence of parasitoids attacking endemic spruce budworm (Lepidoptera: Tortricidae) populations in New Brunswick. Can. Ent. 108: 10451052.CrossRefGoogle Scholar
Morris, R.F. 1947. The spruce budworm in the Maritime Provinces, with particular reference to the Green River watershed. Can. Dep. Agric. Ent. Div. Bi-mon. Prog. Rep. 3(2): 12.Google Scholar
Morris, R.F. 1955. The development of sampling techniques for forest insect defoliators, with particular reference to the spruce budworm. Can. J. Zool. 33: 225294.CrossRefGoogle Scholar
Powell, J.A. 1980. Nomenclature of nearctic conifer-feeding Choristoneura (Lepidoptera: Tortricidae): Historical review and present status. USDA For. Serv. Gen. Tech. Rep. PNW-100. 18 pp.Google Scholar
Pschorn-Walcher, H. 1977. Biological control of forest insects. A. Rev. Ent. 22: 122.CrossRefGoogle Scholar
Rappaport, N.R., and Page, M.. 1985. Rearing Glypta fumiferanae [Hymenoptera: Ichneumonidae] on a multivoltine laboratory colony of the western spruce budworm (Choristoneura occidentalis) [Lepidoptera: Tortricidae]. Entomophaga 30(4): 347352.CrossRefGoogle Scholar
Schaupp, W.C. Jr, 1988. Parasitoids of western budworms, Choristoneura occidentalis and C. retiniana (Lepidoptera: Tortricidae). Ph.D. thesis, University of California, Berkeley, CA. 88 pp.Google Scholar
Stevens, R.E., Carolin, V.M., and Markin, G.P.. 1984. Lepidoptera associated with western spruce budworm. USDA For. Serv. Agric. Hndbk. 622. 63 pp.Google Scholar
Torgersen, T.R., and Beckwith, R.C.. 1974. Parasitoids associated with the large aspen tortrix, Choristoneura conflictana (Lepidoptera: Tortricidae), in interior Alaska. Can. Ent. 106: 12471265.CrossRefGoogle Scholar
Torgersen, T.R., Campell, R.W., Srivastava, N., and Beckwith, R.W.. 1984. Role of parasites in the population dynamics of western spruce budworm (Lepidoptera: Tortricidae) in the Northwest. Environ. Ent. 13: 568573.CrossRefGoogle Scholar
Volney, W.J.A., Liebhold, A.M., and Waters, W.E.. 1984. Host associations, phenotypic variation and mating compatibility of Choristoneura occidentalis and C. retiniana (Lepidoptera: Tortricidae) populations in south-central Oregon. Can. Ent. 116: 813826.CrossRefGoogle Scholar
Waters, W.E., and Volney, W.J.A.. 1985. Sampling and analysis of endemic western spruce budworm populations. pp. 124–131 in Bevan, D., and Stoakley, J.T. (Eds.), Site Characteristics and Population Dynamics of Lepidopteran and Hymenopteran Forest Pests (Proc. IUFRO Conf., 1–7 Sept. 1980, Dornoch, Scotland). For. Comm. Res. Dev. Pap. 135, U.K. 139 pp.Google Scholar
Wilkes, A., Coppel, H.C., and Mathers, W.G.. 1948. Notes on the insect parasites of the spruce budworm Choristoneura fumiferana (Clem.) in British Columbia. Can. Ent. 80: 138155.CrossRefGoogle Scholar
Zwölfer, H. 1961. A comparative analysis of the parasite complexes of the European fir budworm, Choristoneura muriana (Hub.), and the North American spruce budworm, C. fumiferana (Clem.). Comm. Inst. Biol. Control, Tech. Bull. 1: 1162.Google Scholar
Zwölfer, H. 1971. The structure and effect of parasite complexes attacking phytophagous host insects. pp. 405–418 in den Boer, P.J., and Gradwell, G.R. (Eds.), Dynamics of Populations. Centre for Agricultural Publishing and Documentation, Wageninigen. 611 pp.Google Scholar