The cabbage seedpod weevil, Ceutorhynchus obstrictus (Coleoptera: Curculionidae) - a review
The cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham), which has recently become established in southern Alberta, is a serious pest of oilseed rape (Brassica napus L.) in Europe and the USA and poses a major threat to the economic sustainability of canola production in western Canada. This paper reviews the biology and control of this pest and identifies future research needs. Control strategies in Europe and the USA have so far relied on insecticides because no cultural or biological control methods have been successful. Research on plant resistance is in progress at several research centres and could provide the long term solution. Several parasitoid species are known to suppress populations of the weevil in Europe and are candidates for biocontrol programs in North America. Current research priorities in western Canada are to quantify the effects of weevil densities on canola seed yield, to establish economic thresholds and to design control strategies that integrate chemical, cultural and biological controls. Research programs should be established to screen a wide range of Brassica germplasm to identify sources of resistance for use in developing resistant cultivars for western Canada. Research on the overwintering ecology and seasonal activity of this weevil is needed to model how its range is likely to expand to other canola growing regions of Canada and to enable forecasting of outbreaks.
Key words: Brassica, oilseed rape, Ceutorhynchinae, Ceutorhynchus assimilis, Ceutorhynchus obstrictus, canola insect pests
LicenseAuthors who publish with the Journal of the Entomological Society of British Columbia agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).