Hostname: page-component-78c5997874-94fs2 Total loading time: 0 Render date: 2024-11-10T14:33:29.820Z Has data issue: false hasContentIssue false

Desiccation resistance in pre-diapause, diapause and post-diapause larvae of Choristoneura fumiferana (Lepidoptera: Tortricidae)

Published online by Cambridge University Press:  09 March 2007

É Bauce*
Affiliation:
Facultéde foresterie et de géomatique, CRBF, Université Laval, Ste-Foy (Québec), G1K 7P4, Canada
E. Han
Affiliation:
Facultéde foresterie et de géomatique, CRBF, Université Laval, Ste-Foy (Québec), G1K 7P4, Canada
*
*Fax: (418) 656 3677 E-mail: eric.bauce@sbf.ulaval.ca

Abstract

Desiccation resistance was examined in pre-diapause, diapause and post-diapause larvae of the spruce budworm, Choristoneura fumiferana (Clemens), in terms of passive water evaporation under three desiccation conditions: freeze-drying, desiccant-drying at 2°C and desiccant-drying 18°C. Diapausing second instar larvae and post-diapause non-feeding second instar larvae showed strongest desiccation resistance: a significant amount of water was retained after repeated drying under desiccating conditions, while pre-diapause first instar larvae and post-diapause feeding instar larvae lost almost all their water content after one or two drying cycles. A hibernaculum covering had no effect on water evaporation. While dead larvae tended to lose significantly more water than their living counterparts, particularly among first instar larvae, such an impact much weaker among diapausing second instar larvae. Desiccation resistance was lost when post-diapause second instar larvae were allowed access to water while the level of desiccation resistance was maintained or enhanced when the larvae did not have access to water. These results are discussed the context of overwintering ecology of the species and possible mechanisms for the desiccation resistance are also discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2001

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

Blomquist, G.J. & Dillwith, J.W. (1985) Cuticular lipids. pp. 117154 in Kerkut, G.A. & Gilbert, L.I. (Eds) Comprehensive insect physiology, biochemistry and pharmacology. Vol. 3. Oxford, Pergamon Press.Google Scholar
Danks, H.V. (1987) Insect dormancy: an ecological perspective. Biological Survey of Canada (Terrestrial Arthropods), Monograph Series 1, Ottawa.Google Scholar
Danks, H.V. (2000) Dehydration in dormant insects. Journal of Insect Physiology 46, 837852.CrossRefGoogle ScholarPubMed
Edney, E.B. (1977) Water balance in land arthropods. New York, Springer-Verlag.Google Scholar
Hadley, N.F. (1970) Water relations of the desert scorpion, Hadrurus arizonensis. Journal of Experimental Biology 53, 547558.CrossRefGoogle ScholarPubMed
Hadley, N.F. (1994) Water relations of terrestrial arthropods. New York, Academic Press.Google Scholar
Han, E.-N. & Bauce, É. (1993) Physiological changes and cold hardiness of spruce budworm larvae, Choristoneura fumiferana (Clem.), during pre-diapause and diapause development under laboratory conditions. Canadian Entomologist 125, 10431053.Google Scholar
Han, E.-N. & Bauce, É. (1995) Non-freeze survival of spruce budworm larvae, Choristoneura fumiferana (Clem.), at sub-zero temperatures during diapause. Entomologia Experimentalis et Applicata 75, 6574.CrossRefGoogle Scholar
Han, E.-N. & Bauce, É. (1995) Glycerol synthesis by diapause larvae in response to the timing of low temperature exposure, and implications for overwintering survival of the spruce budworm, Choristoneura fumiferana. Journal of Insect Physiology 41, 981985.Google Scholar
Han, E.-N. & Bauce, É. (2000) Dormancy in the life cycle of the spruce budworm: physiological mechanisms and ecological implications. Recent Research Developments in Entomology 3, 4354.Google Scholar
Lundheim, R. & Zachariassen, K.E. (1993) Water balance of overwintering beetles in relation to strategies for cold tolerance. Journal of Comprehensive Physiology 163, 14.CrossRefGoogle Scholar
Palli, S.R., Ladd, T.R., Ricci, A.R., Primavera, M., Mungrue, I.N., Pang, A.S.D. & Retnakaran, A. (1998) Synthesis of the same two proteins prior to larval diapause and pupation in the spruce budworm, Choristoneura fumiferana. Journal of Insect Physiology 44, 509524.Google Scholar
Ramlov, H. & Lee, R.E. (2000) Extreme resistance to desiccation in overwintering larvae of the gall fly Eurosta solidaginis (Diptera, Tephritidae). Journal of Experimental Biology 203, 783789.Google Scholar
Ring, R.A. & Danks, H.V. (1994) Desiccation and cryoprotection: overlapping adaptations. Cryo Letters 15, 181190.Google Scholar
Robinson, W. (1928) Water conservation in insects. Journal of Economic Entomology 21, 897902.CrossRefGoogle Scholar
Zachariassen, K.E. (1991) The water relations of overwintering insects. pp. 4763 in Lee, R.E. Jr. & Denlinger, D.L. (Eds) Insects at low temperature. New York, Chapman and Hall.Google Scholar