|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Journal of Experimental Biology, Vol 203, Issue 4 783-789, Copyright © 2000 by Company of Biologists
JOURNAL ARTICLES |
H Ramlov and RE Lee
Roskilde University, Department of Life Sciences and Chemistry, Building 16.1, DK-4000, Roskilde, Denmark.
During winter, larvae of the goldenrod gall fly Eurosta solidaginis are exposed for extended periods to severe low ambient temperatures and low humidities within plant galls. The resistance of these larvae to desiccation at various temperatures and humidities, the transition (critical) temperature, and the effects of treatment with organic solvents on the larval rates of water loss and on changes in osmolality during desiccation were examined. The water loss rates of the flesh fly Sarcophaga crassipalpis under desiccating conditions were also measured. The water permeability of the cuticle of E. solidaginis larvae was very low (0.038 microgram h(-1 )cm(-2 )Pa(-1) at 20 C and 4% relative humidity) compared with that of larvae of other species. The value for E. solidaginis is equivalent to that of the very drought-resistant larvae of the tenebrionid beetle Tenebrio molitor (0.038 microgram h(-1)cm(-2)Pa(-1) at 30 C). In contrast, the permeability of larvae of the flesh fly Sarcophaga crassipalpis at 20 C and 4 % relative humidity was 0.331 microgram h(-1) cm(-2)Pa(-1). The thermal dependence of the cuticular permeability increased with temperature by approximately 0.0010 +microgram h(-1) cm(-2)Pa(-1) C(-1) in the interval between 4 and 40 C. At the transition temperature of 40 C, the thermal dependence of the permeability increased abruptly to 0.0400 microgram h(-1)cm(-2)Pa(-1) C(-1). Larvae treated with hexane and acetone remained remarkably resistant to water loss. However, treatment with chloroform:methanol increased the water loss rate approximately 25-fold. During desiccation at 4 C and 4% relative humidity for 21 days, E. solidaginis larvae showed a mass loss of 18.5+/-4.4 % (mean +/- s.e.m., N=6). Animals dried under the same conditions over the same period showed a haemolymph osmolality of 851+/-75 mosmol kg(-1) (N=4). Larvae freshly removed from the galls showed a haemolymph osmolality of 918+/-67 mosmol kg(-1)(N=3). A higher osmolality in the dried compared with the fresh larvae would have been expected. The present observation suggests that important ions in the haemolymph may have been excreted or rendered osmotically inactive during desiccation.
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati 
Twitter What's this?
This article has been cited by other articles:
|
|
 |
|
  B. N. Philip, S.-X. Yi, M. A. Elnitsky, and R. E. Lee Jr Aquaporins play a role in desiccation and freeze tolerance in larvae of the goldenrod gall fly, Eurosta solidaginis J. Exp. Biol., April 1, 2008; 211(7): 1114 - 1119. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Williams and R. E. Lee Jr Plant senescence cues entry into diapause in the gall fly Eurosta solidaginis: resulting metabolic depression is critical for water conservation J. Exp. Biol., December 1, 2005; 208(23): 4437 - 4444. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S.-X. Yi and R. E. Lee Jr Changes in gut and Malpighian tubule transport during seasonal acclimatization and freezing in the gall fly Eurosta solidaginis J. Exp. Biol., May 15, 2005; 208(10): 1895 - 1904. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Williams, N. C. Ruehl, and R. E. Lee Jr Partial link between the seasonal acquisition of cold-tolerance and desiccation resistance in the goldenrod gall fly Eurosta solidaginis (Diptera: Tephritidae) J. Exp. Biol., December 1, 2004; 207(25): 4407 - 4414. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. L. Hansen, H. Ramlov, and P. Westh Metabolic activity and water vapour absorption in the mealworm Tenebrio molitor L. (Coleoptera, Tenebrionidae): real-time measurements by two-channel microcalorimetry J. Exp. Biol., February 1, 2004; 207(3): 545 - 552. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. B. Williams, J. D. Shorthouse, and R. E. Lee Jr Extreme resistance to desiccation and microclimate-related differences in cold-hardiness of gall wasps (Hymenoptera: Cynipidae) overwintering on roses in southern Canada J. Exp. Biol., July 15, 2002; 205(14): 2115 - 2124. [Abstract] [Full Text] [PDF]
|
|
