QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Williams, J. B. Articles by Lee, R. E. Search for Related Content PubMed PubMed Citation Articles by Williams, J. B. Articles by Lee, R. E., Jr

Extreme resistance to desiccation and microclimate-related differences in cold-hardiness of gall wasps (Hymenoptera: Cynipidae) overwintering on roses in southern Canada

Jason B. Williams^1,*, Joseph D. Shorthouse² and Richard E. Lee, Jr¹

¹ Department of Zoology, Miami University, Oxford, OH 45056, USA
² Department of Biology, Laurentian University, Sudbury, Ontario, Canada P3E 2C6

View larger version (27K): [in a new window]   Fig. 1. Weekly mean temperatures from September to May 1999-2000 (A) and daily minimum temperatures from 30 December to 26 February 1999-2000 (B) near Sudbury, Ontario, Canada. Snow cover indicates continuous days of at least 10 cm of snowpack, the period represented in B. Subnivean temperatures were recorded at the ground surface while supranivean temperatures were recorded 25 cm above the ground.

View larger version (19K): [in a new window]   Fig. 2. Supercooling point (A), glycerol concentration (B), rate of water loss (C) and body water content (D) for Diplolepis spinosa, D. gracilis and D. radicum prepupae during winter acclimation at 5 °C. Data points that have, but do not share, letters are significantly different. Values are means ± S.E.M. (N=8). Some S.E.M. are within the size of the symbol.

View larger version (15K): [in a new window]   Fig. 3. Supercooling point (mean ± S.E.M., N=8) for cynipid prepupae overwintering in supranivean and subnivean galls. S.E.M. values for D. gracilis are within the symbol.

View larger version (57K): [in a new window]   Fig. 4. Total hemolymph osmolality and the glycerol component of total osmolality for the six cynipid species examined under midwinter conditions. Values are means ± S.E.M. (N=5-8).

View larger version (13K): [in a new window]   Fig. 5. Effects of temperature on water permeability for prepupae of Diplolepis spinosa collected at Medicine Hat, Alberta, Canada. The transition temperature for this species was 33.5 °C. The equation for the regression line below the transition temperature is y=0.028x+0.18 (r2=0.99), where y is cuticular permeability (µg h-1 cm-2 mmHg-1) and x is temperature (°C), and the equation for the regression line above the transition temperature is y=0.426x-13.08 (r2=0.91). Values are means ± S.E.M. (N=5-8).