Local and Landscape-Scale Features Influence Bumble Bee (Hymenoptera: Apidae) Bycatch in Bertha Armyworm Mamestra configurata (Lepidoptera: Noctuidae) Pheromone-Baited Monitoring Traps

The bertha armyworm (BAW) Mamestra configurata Walker is a significant pest of canola Brassica napus L. (Brassicales: Brassicaceae) in western Canada. Its activity is monitored through a large network of pheromone-baited monitoring traps as a part of the Prairie Pest Monitoring Network across the Canadian Prairies. The unintentional bycatch of bee pollinators in pheromone-baited traps targeting moth pests occurs in many agroecosystems and may have repercussions for biodiversity and pollination services of wild plants and managed crops. We conducted field experiments to determine the abundance and diversity of bees attracted to green-colored BAW pheromone-baited traps across the canola growing regions of Alberta, Canada. A higher species diversity and more bumble bees were captured in BAW pheromone-baited than in unbaited control traps. Bombus rufocinctus Cresson (Hymenoptera: Apidae) was the most commonly captured species. Few other wild bees or honey bees Apis mellifera L. (Hymenoptera: Apidae) were captured during this study. Additionally, we evaluated the influence of local and landscape-level habitat features on bee bycatch. Local flowering plant abundance improved overall model fit but did not directly impact bee bycatch. The proportion of natural and seminatural habitat, and especially forested area, in the area surrounding monitoring traps affected bee bycatch. Both local and landscape-scale factors were important in this study and often have combined effects on bee communities. This study provides recommendations to reduce the bycatch of beneficial bee pollinators in a large-scale pheromone-baited monitoring network.

Interactions between Camelina sativa (Brassicaceae) and insect pests of canola

In an investigation of Camelina sativa (Linnaeus) Crantz (Brassicaceae) and five common insect pests of canola (Brassica napus Linnaeus) (Brassicaceae), little feeding damage to the plant was inflicted by crucifer-feeding specialist flea beetles (Phyllotreta Chevrolat species) (Coleoptera: Chrysomelidae), Delia Robineau-Desvoidy (Diptera: Anthomyiidae) root maggots, or diamondback moth (Plutella xylostella Linnaeus (Lepidoptera: Plutellidae)). In choice tests, diamondback moths laid fewer eggs on C. sativa than on B. napus leaves. Diamondback moth larvae consumed less C. sativa leaf tissue, and tended to have a longer developmental period on C. sativa. Larvae of the polyphagous bertha armyworm (Mamestra configurata Walker (Lepidoptera: Noctuidae)) had similar feeding levels on C. sativa and B. napus plants. However, there was a longer developmental period from larval to pupal stage and pupae weighed less when fed on C. sativa foliage, suggesting that C. sativa contains antibiosis factors against bertha armyworm. Two strains of aster yellows phytoplasma, 16SrI-A and 16SrI-B, were identified in C. sativa and in Macrosteles quadrilineatus (Forbes) (Hemiptera: Cicadellidae). Differences in incidence of aster yellows and abundance of M. quadrilineatus were observed among lines of C. sativa. The findings confirm that C. sativa is unlikely to support high populations of these insect pests on the Canadian prairies.