Thus, the pea leaf weevil has one generation per year with two flights: the first in the fall, when newly eclosed adults move to overwintering sites, and another in the spring, when pea fields are colonized by reproductive adults (Figure 6). These flights are mediated by semiochemical cues, including host plant volatiles and pheromones. A trapping system based on synthetic versions of these volatiles is a good step towards integrated management of this pest. The first use of this tool will be to monitor range expansion and to study the phenology of the pea leaf weevil. Later, the lure may be incorporated in control strategies, such as an "attract and kill" strategy, which pairs the attractive lure with a pesticide. If real populations in the fields can be correlated with trap captures, this lure may be useful for predicting future pea leaf weevil damage.
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The objective of this research is to develop an optimal semiochemical trap to monitor the pea leaf weevil in the Prairie Provinces. The current goals that will be discussed here include developing an optimally attractive lure and using it to monitor pea leaf weevil phenology. In 2013, we tested the attractiveness of two doses (21 mg and 42 mg) of aggregation pheromone in two release devices (250 µL and 400 µL Eppendorf tubes). We tested these pheromone lures with and without host plant volatiles (Table 1; Figure 7). This experiment was performed in southern Alberta pea fields during the spring and fall adult activity periods. We found no difference in attractiveness between the two doses and release devices tested for aggregation pheromone. However, the addition of bean volatiles significantly increased the attractiveness of the lure.