Most studies examining effects of extreme temperature on insect immunity have focused on negative impacts of high-temperature exposure. Although largely unexplored, a recent study suggests that repeated exposure to freezing temperature may enhance insects’ ability to survive microbial challenge. To determine if repeated low-temperature exposure impacts innate immunity of the goldenrod gall fly, Eurosta solidaginis, we counted hemocyte number, measured phenoloxidase activity and assessed antibacterial activity, and I examined up-regulation of immune-related genes in winter-acclimated larvae 24 h or 96 h after they were subjected to either zero (control), five, or ten diurnal exposures to -18°C. To assess if time spent frozen, rather than freezing and thawing, influenced immunity, we also counted examined immune factors in larvae exposed to a single, six-day constant freeze. Repeated freezing negatively impacts hemocyte number, antimicrobial activity against Gram-negative bacteria, and had varied effects on phenoloxidase activity in the goldenrod gall fly. I suggest the effects of repeated cold exposure on insect immunity are governed by energy trade-offs and are not likely to mimic the effects of a single freeze.
|Advisor:||Williams, Jason, McCracken, Vance|
|Commitee:||DiSalvo, Susanne, McCracken, Vance, Williams, Jason|
|School:||Southern Illinois University at Edwardsville|
|School Location:||United States -- Illinois|
|Source:||MAI 58/01M(E), Masters Abstracts International|
|Subjects:||Entomology, Microbiology, Immunology|
Copyright in each Dissertation and Thesis is retained by the author. All Rights Reserved
The supplemental file or files you are about to download were provided to ProQuest by the author as part of a
dissertation or thesis. The supplemental files are provided "AS IS" without warranty. ProQuest is not responsible for the
content, format or impact on the supplemental file(s) on our system. in some cases, the file type may be unknown or
may be a .exe file. We recommend caution as you open such files.
Copyright of the original materials contained in the supplemental file is retained by the author and your access to the
supplemental files is subject to the ProQuest Terms and Conditions of use.
Depending on the size of the file(s) you are downloading, the system may take some time to download them. Please be