Examining the Biology and Monitoring Tools of Sitodiplosis mosellana in the Peace River region, Alberta

  • Author / Creator
    Jorgensen, Amanda
  • Wheat midge, Sitodiplosis mosellana Géhin (Diptera: Cecidomyiidae), is an invasive pest of wheat that has spread into the Peace River region of Alberta, Canada. The biology and monitoring of wheat midge has not previously been examined in this region. Wheat midge overwintering density and parasitism rates were examined by rearing field collected soil, and overwintering mortality was determined by rearing wheat midge in soil in different conditions. Parasitism rates were high (>50%). Rates of adult emergence were higher when soil was held under controlled conditions overwinter. Patterns of adult wheat midge emergence in the field were compared to published bioclimatic models. The differences between adult emergence in the Peace River region were great enough that development of a regionally-optimized model is necessary. In the Peace River region, adults emerged 300 GDD base 7 °C after a rainfall event. Multiple peaks of wheat midge emergence and capture on pheromone-baited traps were observed. Capture of adult wheat midges on different delta traps (orange or green), and pheromone lures (Scotts™ flex, Scotts™ septa, or Great Lakes IPM™ septa) were compared. In 2017, delta traps with a larger surface area captured more midges, and traps baited with the Scotts™ flex lure captured more midges than the Great Lakes IPM™ septa lure. Different un-baited yellow sticky cards (Great Lakes IPM™, Alpha Scents™, or Alpha Scents™ rolled into a cylinder) were compared for wheat midge capture. More midges were captured on the smaller, Great Lakes IPM™ unbaited yellow sticky cards than the two, larger Alpha Scents™ cards. We examined relationships between capture of adult midges on pheromone or yellow sticky card traps to larval density by extracting larvae from wheat heads at the same sites. We found no relationships between pheromone-baited traps and larval densities and were unable to determine relationships between yellow sticky cards and larval densities. To compare harvest metrics to trap capture, we collected harvest samples (1 m2) at the same sites. We found no relationships between harvest metrics and pheromone-baited traps and were unable to determine relationships with yellow sticky traps. We examined the longevity of adult females in the lab and found no differences in longevity between females held individually or held with males. In commercial wheat fields, we conducted hourly counts of active female wheat midges to test circadian flight patterns. Peak wheat midge flight occurred at twilight. Soil core samples were collected from sites before monitoring to determine relationships with adult midge densities. No relationships were found between soil core samples and captures of adult midges in the spring.

  • Subjects / Keywords
  • Graduation date
    Spring 2019
  • Type of Item
  • Degree
    Master of Science
  • DOI
  • License
    Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.