Improving cactus moth SIT by enhancing dispersal, sexual performance, and longevity: The cactus moth, Cactoblastis cactorum, is an invasive pest that threatens the prickly pear (Opuntia sp.) cactus production and biodiversity. This is of particular importance in our area of the US, where prickly pear cacti are used for a variety of purposes, including food. By using hormetic treatments, like those studied and developed for the fruit flies, we are working on improving the cactus moth SIT program. This project has an added component of taking the information learned in the lab bio assays into the field in a series of actual SIT releases. I am collaborating with two research entomologists at the USDA-ARS for this project: James E. Carpenter and Stephen D. Hight, and my former post-doctoral advisor at the University of Florida Daniel A. Hahn.
Water balance and gene expression during water flux: dehydration, rehydration, and overhydration are three very different stressors that share the common aspect of dealing with water flux. Different groups of genes are differentially expressed during each of these unique processes. Using the Antarctic midge, we took transcriptomic and proteomic approaches to shine a light on what happens at the cellular level during periods of water flux.
Antarctic stress physiology: a NSF-funded research expedition to Palmer Station, Antarctica allowed us to study some of the most extreme stress responses in the planet. The Antarctic midge uses a variety of mechanisms to survive the harsh Antarctic winters and summers. There are several species of mites, including a tick, that also call Antarctica home and are well adapted for freezing, dry, and windy polar climates.
Medical Entomology stress physiology: hematophagous insects have to cope with an additional stress in order to complete their lifecycle; blood feeding. Blood-feeding is a multifarious stressor that involves drastic increases in temperature and water content, as well as, increases in solutes and harmful compounds. Mosquitoes and bed bugs (among others) are able to eat, digest, and use those blood meals to make eggs by employing heat shock proteins to maintain their normal cellular machinery working during the heat shock and overhydration bout involved in taking a blood meal.
Heat shock proteins in the field: heat shock proteins are very important molecular chaperones that are crucial during development but particularly important during periods of environmental stress in order to prevent protein misfolding and aggregation. I investigated their role during regular development in a typical 24-hr cycle in the apple maggot, Rhagoletis pomonella; while the larvae are feeding inside apples in a typical hot Midwestern US summer day.
Developing new gene knockdown (RNAi) delivery methods: we recently look for a way to effectively deliver dsRNA into larval mosquitoes in their aquatic environment. We came up with a low-cost, relatively easy solution to this common problem by taking advantage of basic mosquito biology, osmosis, and concentration gradients.