Evenden: The development of a semiochemical monitoring and detection system for the diamondback moth on canola
Date: 2009
Term: 3 years
Status: Completed
Researcher(s): Dr. Maya Evenden, Department of Biological Sciences, University of Alberta, Dr. L. Dosdall, G. Gries, K. Fry, A. Keddie, S. Meers, M Hartman.
SaskCanola Investment: $13,867
Total Project Cost: $27,735.18
Funding Partners: n/a
Project Summary
Producers are encouraged to use pheromone baited traps to monitor diamondback moth flight. This information can predict expected larval densities in their crop. However, an economic threshold based on moth trap counts and continued larval sampling after moths are detected in traps still needs to be developed.
In the Canadian prairies, diamondback moth (Plutella xylostella) is considered a serious pest of canola. Infestation of diamondback moth in the Canadian prairies is due primarily to migration of adult moths on wind currents from the south each spring. If sufficient numbers of moths arrive in canola crops and lay eggs, the resulting larvae and subsequent generations can cause significant damage to canola as they feed on all plant parts at various stages within the growing season. Under outbreak conditions, insecticide application is necessary to control diamondback moth and prevent large yield losses.
Ellis Chan and Christine Miluch sampling diamondback moth in canola.
Source: Maya EvendenPheromone baited traps can be used to monitor and detect male diamondback moths and a pheromone trapping network is in place in the Prairie provinces. However, female‐baited traps routinely capture more male moths than synthetic traps indicating that key chemical constituents may be missing from the lures currently used. Further, the significance of male moth capture to population densities has not been determined for diamondback moth on canola.
The overall objective of this research was to develop a semiochemical based monitoring system for diamondback moth on canola in western Canada. The research evaluated various commercial lures that are currently available to producers and determined the best lure type, age, and position in which to use these tools in the field. As well, other pheromone blends with various ratios of the known pheromone components with and without the addition a greenleaf volatile were tested. Finally, this research evaluated the potential of diamondback moth trap capture in traps baited with commercially available pheromone lures to predict larval infestation in canola in Alberta.
The findings of this study provided several easy to implement recommendations to improve the efficacy of the pheromone based monitoring system currently used to monitor diamondback moth activity in the Prairie provinces. The results show that PheroTech (now ConTech) lures were consistently among the most attractive of the commercial lures and their continued use in the Prairie Pheromone Monitoring Network is recommended. Lures should be rotated on a 6 week rotation schedule and not on the 3‐week rotation schedule as is currently used in the Prairie Pheromone Monitoring Network. ConTech should dispense pheromone into grey rather than red rubber septa to improve the attractiveness of their product. Producers should position traps at a height of 50 cm along the crop edge instead of the 2m height that is currently the standard used in the Prairie Pheromone Monitoring Network. Several recommendations were also made to improve the pheromone formulation that may result in the development of a more attractive, commercially available lure through future research and collaboration with ConTech.
The findings also demonstrate that pheromone‐based monitoring is related to infestation levels, at least at moderate population densities at the end of the field season. Producers are encouraged to use pheromone‐baited traps to monitor diamondback moth flight and this information can predict expected larval densities in their crop. However, further research is needed to develop an economic threshold based on moth trap counts and continued larval sampling after moths are detected in traps is recommended.
Scientific Publications
Evenden, M.L and Gries, R. 2010. Assessment of commercially available pheromone lures for monitoring diamondback moth (Lepidoptera: Plutellidae) in canola. Journal of Economic Entomology 103: 654-661.
Miluch, C.E. 2010. Development of a semiochemical-based monitoring system for diamondback moth, Plutella xylostella (L.) (Lepidoptera: Plutellidae), in canola in Alberta. MSc thesis, Department of Agricultural, Food and Nutritional Science, University of Alberta (to be defended 23 July, 2010).