Assessing the role of biological control agents of cutworms (Lepidoptera: Noctuidae) in field crops in the Canadian Prairies
| dc.contributor.author | Wanigasekara, R W M Udari M | |
| dc.contributor.examiningcommittee | Currie, Rob (Entomology) | en_US |
| dc.contributor.examiningcommittee | Costamagna, Alejandro (Entomology) | en_US |
| dc.contributor.examiningcommittee | Lawley, Yvonne (Plant Science) | en_US |
| dc.contributor.examiningcommittee | Peterson, Julie (Entomology, University of Nebraska–Lincoln) | en_US |
| dc.contributor.supervisor | Sharanowski, Barbara (Entomology) | en_US |
| dc.date.accessioned | 2021-01-20T17:04:39Z | |
| dc.date.available | 2021-01-20T17:04:39Z | |
| dc.date.copyright | 2020-12-02 | |
| dc.date.issued | 2020-12-02 | en_US |
| dc.date.submitted | 2020-12-02T20:21:06Z | en_US |
| dc.degree.discipline | Entomology | en_US |
| dc.degree.level | Doctor of Philosophy (Ph.D.) | en_US |
| dc.description.abstract | Cutworms can cause serious damage to crops in the Prairies Ecozone of southern Manitoba, Saskatchewan, and Alberta. By far, the best-known biocontrol agents of pest cutworms are parasitoids. However, the community of parasitoids is poorly known, and parasitoids remain as an unutilized resource for controlling cutworms. Thus, this study is designed to identify the economically important cutworms, to characterize the taxonomy and biology of the parasitoid community attacking those cutworm species in relationships to cutworm biology, and to identify and characterize potential plant resources that can enhance pest control services of parasitoids in the Prairies. Cutworms, including redbacked, darksided, dingy, and army cutworms were collected from infested fields and reared in the laboratory conditions during 2012-2016. Hymenopteran parasitoids emerged from cutworms were 64% Encyrtidae, 23% Ichneumonidae, and 13% Braconidae. The percent parasitized by each species was below 10% throughout the study period. Copidosoma bakeri and Copidosoma cuproviridis were the two Encyrtidae species recorded according to their original descriptions, but data obtained from their morphology, morphometry, genetic, collection locality, and host data support did not provide support for two species and new revision for this genus is needed. C. bakeri was the most common parasitoid recorded in the Prairies, and 89.1 % of hymenopteran parasitoids recorded from Manitoba were C. bakeri. Thus, C. bakeri was the only species capable of controlling cutworms in Manitoba. In contrast, both Cotesia spp. and C. bakeri were parasitizing cutworm communities in Alberta. All other hymenopteran parasitoids were recorded in small numbers or recorded only once during the study period. Finally, I assessed potential cover crops that could provide resources to parasitoids with respect to buckwheat, camelina, canola, chickling vetch, field pennycress, flax, oriental mustard, phacelia, and tillage radish and found camelina is the best candidate for cover cropping. This study is the critical first step in developing sustainable management practices for cutworms in canola and will develop the framework for future research on parasitoids and habitat management to develop effective biocontrol strategies. | en_US |
| dc.description.note | February 2021 | en_US |
| dc.identifier.uri | http://hdl.handle.net/1993/35282 | |
| dc.language.iso | eng | en_US |
| dc.rights | open access | en_US |
| dc.subject | Parasitoid taxonomy | en_US |
| dc.subject | Species delimitation | en_US |
| dc.subject | Habitat management | en_US |
| dc.subject | Conservation biological control | en_US |
| dc.subject | Cover crops | en_US |
| dc.subject | Parasitoid wasp host preferences | en_US |
| dc.subject | Parasitoid longevity and survival | en_US |
| dc.subject | Integrated pest management | en_US |
| dc.subject | Phenological match | en_US |
| dc.title | Assessing the role of biological control agents of cutworms (Lepidoptera: Noctuidae) in field crops in the Canadian Prairies | en_US |
| dc.type | doctoral thesis | en_US |
| local.subject.manitoba | yes | en_US |