The Risk of Wireworms (Coleoptera: Elateridae) to Manitoban Crop Production
Lead Researcher: Ivan Drahun
Wireworms are one of the most significant threats to crop yield in Manitoba. While the adult click beetles pose no major threat to their host plants, the soil-dwelling larval wireworms are serious pests to crops including corn, potato, grains and soybean. The major problem with wireworms is their extended life cycle, which can last up to five years to complete a single generation. Spending the majority of their life cycle underground, in addition to no perfect method of protection, these pests become very difficult to control. Click beetles enter agricultural areas from undisturbed, non-farmed habitats – areas never treated with insecticides that allow populations to build up in high numbers. Once they have invaded a field, wireworms pose a serious risk to crop in rotation for years to come and can cause significant yield losses in infested fields.
Our objective was to evaluate the threat that wireworms pose to present and future crop production in Manitoba through field surveillance, molecular diagnostics and behavioural bioassays. We trapped wireworms and click beetles in fields across Manitoba to determine species composition and relative abundance of the major species. To determine the population structure and unravel any cryptic species, we performed molecular diagnostics focusing on the COX1 mitochondrial gene. We also wanted to observe wireworm damage by exposing planted soybean seeds to varying wireworm densities to develop an economic threshold for H. bicolor - the major wireworm species found in Manitoba. We took our study further by analyzing the effect that soil composition and seed treatments have on the feeding behaviour of H. bicolor wireworms. This information will be critical in developing a scouting protocol and economic threshold to aid in wireworm management in Manitoba.
Insights into the Repellency Effect of DEET on the American Dog Tick (Dermacentor variabilis)
Lead Researcher: Cody Koloski
Ticks are the second most medically important vector of both human and veterinary pathogens. Ticks are known to spread pathogens responsible for Lyme Disease, Tularemia, and Rocky Mountain Spotted Fever. The best method humans currently have at combating the spread of these pathogens are repellents. The most commonly used repellent in the world contains DEET which is the active ingredient in many commercial repellents such as OFF! Despite the >60 years of DEET use, the molecular way in which it repels ticks is still poorly understood.
My research looks to find out what is happening at the DNA/RNA level in ticks that are exposed to DEET to determine what genes are being expressed. I am also testing the efficacy of DEET to determine whether stronger concentrations of DEET should be made available to consumers.