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EFFECT OF TEMPERATURE ON MORTALITY AND RECOVERY OF SPRUCE BUDWORM (LEPIDOPTERA: TORTRICIDAE) EXPOSED TO BACILLUS THURINGIENSIS BERLINER

Published online by Cambridge University Press:  31 May 2012

Kees van Frankenhuyzen
Affiliation:
Forest Pest Management Institute, Canadian Forestry Service, PO Box 490, Sault Ste. Marie, Ontario, Canada P6A 5M7
Carl W. Nystrom
Affiliation:
Forest Pest Management Institute, Canadian Forestry Service, PO Box 490, Sault Ste. Marie, Ontario, Canada P6A 5M7

Abstract

Spruce budworm larvae were bioassayed against Bacillus thuringiensis Berliner to study the effect of temperature on the expression of toxicity. Temperatures between 16 and 28°C did not affect the ultimate level of toxicity (LC50). However, LT50’s increased from 2–8 days at 28°C to 11–20 days at 16°C, depending on concentration of the pathogen. When larvae were force-fed with a single dose, temperature had a similar effect on the time course of mortality without affecting the level of mortality. Feeding inhibition of force-fed larvae commenced immediately after dosing. Larvae that did not recover died without further feeding, even at lower temperatures when death occurred 2–3 weeks after dosing. Recovering larvae resumed feeding after 2 (28°C) to 6 (13°C) days. Recovered larvae took longer to develop and produced lighter pupae than untreated larvae. Our data suggest that temperature-dependent feeding and recovery did not contribute to quicker death at higher temperatures. Expression of the toxin itself appears to depend on temperature, possibly through the influence of temperature on metabolic rate of affected gut cells. Implications of these findings for the efficacy of spruce budworm control operations are discussed.

Résumé

On a étudié l’effet de la température sur l’expression de la toxicité du Bacillus thuringiensis Berliner à rencontre des larves de la tordeuse des bourgeons de l’épinette. Entre 16 et 28°C, la température n’a pas affecté le niveau ultime de toxicité (LC50). Cependant les LT50 ont augmenté de 2–8 jours à 28°C, jusqu’à 11–20 jours à 16°C, selon la concentration du pathogène. Lorsque les larves ont été forcées d’ingérer une dose unique, la température a eu un effet similaire sur la chronologie de la mortalité, sans affecter son niveau. L’arrêt de l’alimentation chez les larves forcées d’ingérer le produit est apparu dès après le traitement. Les larves qui n’ont pu récupérer sont mortes sans reprendre de nourriture, même aux basses températures alors que la mort ne survenait que 2–3 semaines après la traitement. Les larves qui ont récupéré ont recommencé à s’alimenter après 2 (28°C) à 6 jours (13°C). Les larves ayant récupéré ont mis plus de temps à se développer et ont produit des pupes plus petites que les larves non traitées. Nos données indiquent que la thermo-dépendance de l’alimentaiton et de la récupération ne contribuent pas à la mortalité accélérée observée à haute température. C’est l’expression même de la toxine qui semble dépendre de la température, possiblement via l’effect de celle-ci sur le taux métabolique des cellules entériques affectées. On discute des implications de ces observations pour les opérations de lutte contre la tordeuse.

Type
Articles
Copyright
Copyright © Entomological Society of Canada 1987

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References

Beegle, C.C., Couch, T.L., Alls, R.T., Versoi, P.L., and Lee, B.L.. 1986. Standardization of HD-1-S-1980: U.S. standard for assay of lepidopterous-active Bacillus thuringiensis. Bull. ent. Soc. Am. 32: 4445.Google Scholar
Burges, H.D. et al. , 1967. The standardization of products based on Bacillus thuringiensis: tests on three candidate reference materials. pp. 314336in van der Laan, P.A. (Ed.), Insect Pathology and Microbial Control. North-Holland Publishing Company, Amsterdam.Google Scholar
Carrow, J.R. 1983. B.t. and the spruce budworm — 1983. Proceedings of a seminar held in Fredericton, N.B., Sept. 8 1983. N.B. Dept. of Natural Resources. 91 pp.Google Scholar
Chalfant, R.B. 1973. Cabbage looper: effect of temperature on toxicity of insecticides in the laboratory. J. econ. Ent. 66: 339341.CrossRefGoogle Scholar
Dixon, W.J. 1983. BMDP statistical software. University of California Press, Los Angeles, CA.Google Scholar
Farghal, A.I. 1982. Effect of temperature on the effectiveness of Bacillus thuringiensis var. israelensis against Culex pipiens molestus Forsk larvae. Zeitschr. Angew. Ent. 94: 412419.Google Scholar
Fast, P.G. 1977. Bacillus thuringiensis endotoxin: on the relative role of spores and crystals in toxicity to spruce budworm larvae (Lepidoptera: Tortricidae). Can. Ent. 109: 15151519.CrossRefGoogle Scholar
Fast, P.G. 1981. The crystal toxin of Bacillus thuringiensis. pp. 223248in Burges, H.D. (Ed.), Microbial Control of Pests and Plant Diseases, 1970–1980. Academic Press, London.Google Scholar
Fast, P.G., Kettela, E.G.. and Wiesner, C.J.. 1986. Assessment of the efficacy of Bacillus thuringiensis against the spruce budworm. New Brunswick Spray Efficacy Research Group Report C/86/005. 37 pp.Google Scholar
Fast, P.G., and Régnière, J.. 1984. Effect of exposure time to Bacillus thuringiensis on mortality and recovery of the spruce budworm (Lepidoptera: Tortricidae). Can. Ent. 116: 123130.CrossRefGoogle Scholar
Finney, D.J. 1971. Probit analysis. Cambridge University Press.Google Scholar
Grisdale, D. 1970. An improved method for rearing large numbers of spruce budworm, Choristoneura fumiferana (Lepidoptera: Tortricidae). Can. Ent. 102: 11111117.CrossRefGoogle Scholar
Heimpel, A.M., and Angus, T.A.. 1959. The site of action of crystalliferous bacteria in Lepidoptera larvae. J. Insect Pathol. 1: 152170.Google Scholar
Hulme, M.A., Ennis, T.J., and Lavallee, A.. 1983. Current status of Bacillus thuringiensis for spruce budworm control. For. Chron. 59: 5861.CrossRefGoogle Scholar
Knowles, B.H., Thomas, W.E., and Ellar, D.J.. 1984. Lectin-like binding of Bacillus thuringiensis var. kurstaki lepidopteran-specific toxin is an initial step in insecticidal action. FEBS Lett. 168: 197202.CrossRefGoogle ScholarPubMed
Lacey, L.A., and Federici, B.A.. 1979. Pathogenesis and midgut histopathology of Bacillus thuringiensis in Simulium vittatum (Diptera: Simulidae). J. Invert. Path. 33: 171182.CrossRefGoogle Scholar
Morris, O.N., Cunningham, J.C., Finney-Crawley, J.R., Jaques, R.P., and Kinoshita, G.. 1986. Microbial insecticides in Canada: their registration and use in agriculture, forestry and public and animal health. A report prepared by the Special Committee of the Science Policy Committee, Ent. Soc. of Canada. Suppl. Bull. Ent. Soc. Can. 18. 43 pp.Google Scholar
Percy, J., and Fast, P.G.. 1983. Bacillus thuringiensis crystal toxin: ultrastructural studies of its effect on silkworm midgut cells. J. Invert. Path. 41: 8698.CrossRefGoogle Scholar
Retnakaran, A. 1983. Spectrophotometric determination of larval ingestion rates in the spruce budworm (Lepidoptera: Tortricidae). Can. Ent. 115: 3140.CrossRefGoogle Scholar
Retnakaran, A., Lauzon, H., and Fast, P.G.. 1983. Bacillus thuringiensis induced anorexia in the spruce budworm, Choristoneura fumiferana. Ent. exp. appl. 34: 233239.CrossRefGoogle Scholar
Smirnoff, W.A. 1967. Influence of temperature on the rate of development of six varieties of the Bacillus cereus group. pp. 125130in van der Laan, P.A. (Ed.), Insect Pathology and Microbial Control. North-Holland Publishing Company, Amsterdam.Google Scholar
Spies, A.G., and Spence, K.D.. 1985. Effect of sublethal Bacillus thuringiensis crystal endotoxin treatment on the larval midgut of a moth, Manduca: SEM study. Tissue Cell 17: 379394.CrossRefGoogle ScholarPubMed
Svestka, M. 1976. The influence of temperature on the effectiveness of biopreparations of Bacillus thuringiensis Berl. Lesnictvi 22: 7786.Google Scholar
Svestka, M., and Vankova, J.. 1984. Action of preparations of Bacillus thuringiensis Berl. against the population of larch budmoth Zeiraphera diniana Gn in spruce growths of the Krkonose (Giant Mountain) region. Zeitschr. Angew. Ent. 98: 164173.CrossRefGoogle Scholar
Walton, G.S., and Lewis, F.B.. 1982. Spruce budworm core B.t. test — 1980. Combined summary CANUSA spruce budworms programs. Northeastern Forest Experiment Station Research Paper NE-506. 12 pp.Google Scholar
Weseloh, R.M., Andreadis, T.G., Dubois, N.R., Moore, R.E.B., Anderson, J.F., and Lewis, F.B.. 1983. Field confirmation of a mechanism causing synergism between Bacillus thuringiensis and the gypsy moth parasitoid, Apanteles melanoscellus. J. Invert. Path. 41: 99103.CrossRefGoogle Scholar
West, R.J., Raske, A.C., Retnakaran, A., and Lim, K.P.. 1987. Efficacy of various Bacillus thuringiensis Berliner var. kurstaki formulations and dosages in the field against the hemlock looper, Lambdina fiscellaria fiscellaria (Guen.) (Lepidoptera: Geometridae) in Newfoundland. Can. Ent. 119: 449458.CrossRefGoogle Scholar