Red Clover Casebearer
The Clover Casebearer Research Project carried out at the University of Alberta was partially funded by Saskatchewan Forage Seed Development Commission for 3 years. The three-chapter Final Report is now available. Please see the Chapter 1 abstract below.
Final Report: Development of pheromone-based mating disruption to control the red clover casebearer. Project Team Leader: Dr. Maya Evenden. Project Team Members: Jennifer Otani, Calvin Yoder, Boyd Mori. April 27, 2014
Abstract
The red clover casebearer, Coleophora deauratella Leinig and Zeller (Lepidoptera:Coleophoridae) is a major pest of red clover (Trifolium pratense L.) grown for seed in and parts of Europe. The efficacy and mechanisms of communication disruption were in small plot trials (0.25 ha) with twist-tie dispensers loaded with either the complete pheromone blend (10:1 ratio of (Z)-7-dodecenyl acetate to (Z)-5-dodecenyl acetate) unattractive major component alone ((Z)-7-dodecenyl acetate). Both formulations reduced C. deauratella orientation to pheromone traps (>99.6%). Interestingly, the unattractive component reduced trap capture to a greater degree than the complete blend. In communication disruption-treated plots, males oriented to dispensers that release the complete pheromone but not the major component. In the laboratory, male C. deauratella antennae became measured by electroantennograms conducted 5 minutes after pre-exposure to either the blend or the major component for 1 hour. Adaptation due to pre-exposure to either formulation resulted in a shift in the pheromone response threshold, antennae from pre-exposed moths responded to a greater degree to high pheromone stimuli dosages (5-50 μg) compared untreated control moths. Antennae from moths held in clean air for 24 hours after pre recovered and responded similarly to pheromone stimuli as antennae from control moths. results suggest that both formulations have the potential to cause communication disruption deauratella but the mechanisms of disruption differ between the two formulations.