IPM and pollinator protection in canola production in the USA

Authors: Reddy, Gadi V.P.; SHARMA, ANAMIKA - Montana State University

Submitted to: Integrative Biological Control
Publication Type: Book / Chapter
Publication Acceptance Date: 12/20/2019
Publication Date: 8/20/2020
Citation: Reddy, G.V., Sharma, A. 2020. IPM and pollinator protection in canola production in the USA. Integrative Biological Control. 20:165-176. https://doi.org/10.1007/978-3-030-44838-7_10.
DOI: https://doi.org/10.1007/978-3-030-44838-7_10

Interpretive Summary: Canola production in the USA has a promising future for growers as well as for the overall economy, despite the presence of some important insect pests, pathogens and weeds. Although conventional pesticides seem to be most reliable tool at present to deal with canola insect pests, pathogens and weeds, caution should be taken in choosing the pesticide, timing and method of application. Even though canola can be self-fertile, pollinators find the copious amount of nectar from the blooming flowers of canola quite attractive, and this attraction of pollinators strengthens the economic value of canola by increasing landscape diversity and improving the health of pollinators. Various biological control methods have shown great potential to perform the same service as various pesticides without the harm to the pollinator community, and these control methods should be promoted among growers. Since canola is a natural attractant for pollinators, better communication between growers and beekeepers is required to reduce possible pesticide drift and the collection of contaminated nectar by bees.

Technical Abstract: Canola belongs to the genus Brassica, and the varieties employed currently yield oil containing less than 2% erucic acid. In the USA, concerted efforts to grow canola began in 1985. Major pests of canola in the USA are the cabbage seedpod weevil (Ceutorhynchus assimilis Paykull) and the flea beetles (Phyllotreta cruciferae Goeze and Phyllotreta striolata Fabricius). The best management of these insect pests still includes pesticides, especially neonicotinoids as seed treatments, while plant pathogens and weeds are managed with conventional fungicide and herbicides. Honey bees and wild solitary bees in various families are the major pollinators of canola, and along with other benefits they increase yield by causing the plant to set seeds earlier, allowing for easier harvesting. While insecticides (including seed treatments) cause greater damage to bees than fungicides and herbicides, all groups of pesticides can be harmful to pollinators, especially when mixed together and with adjuvants. Improving communication between canola growers and beekeepers, selecting low toxicity pesticides, and following label instructions before application all are steps that can reduce bee poisoning. Similarly, increasing plant biodiversity near canola fields to provide habitat and food resources can also improve bee population size and health. A greater focus on cultural and biological management generally would improve pollinator health, and pollinator management should play a major role in the integrated pest management of canola.