Lifetable of the Pollen Beetle (Brassicogethes viridescens)

The rape pollen beetle, Brassicogethes viridescens Fabricius (Coleoptera: Nitidulidae) is an introduced pest of Brassicaceae plants in eastern North America. The predicted geographical expansion of this pest to major canola growing areas in Canada heightened the need for information on the life cycle of B. viridescens . A field study was carried out in 2014, 2015 and 2017 to determine the life cycle relative to the canola crop phenology and accumulated degree-days (DD) in Prince Edward Island, Canada. Sticky traps, manual collection of buds, pupation traps, and adult emergence traps were used to assess the timing of the different life stages. Results showed that B. viridescens were active between late May and early September and required 250-332 DD above a 10°C developmental threshold to complete their development (egg to newly emerged adult) with one generation per year. Photoperiod or food availability but not temperature, were the main driving factors in the life cycle of B. viridescens. Appearance of different life stages coincided with canola phenology, and the number of damaged buds was positively correlated to the number of buds containing B. viridescens larvae. This information can be used as a decision making tool for timing of insecticide application.