Asparagus is globally in decline due partially to increased pest prevalence. One of the main pests is the asparagus miner, a stem-mining fly, that may spread pathogenic fungi (Fusarium spp.). Because conventional pesticides are not sufficient in controlling the asparagus miner, an integrated management program needs to be developed to aid asparagus growers. This dissertation evaluates three different aspects of plant-insect interactions in asparagus fields in order to lay the basis for an IPM program for the miner. These include 1) developing a degree-day model and elucidating the spatial distribution of the asparagus miner within a field so growers can accurately time and place insecticides to achieve increased levels of control with decreased ecological and monetary costs; 2) investigating the natural enemy community of the asparagus miner to lay a foundation for a conservation biological control program; and 3) exploring the chemical ecology of asparagus and its interactions with its arthropod community in order to probe the potential for the use of plant volatiles in IPM. For the first objective, sticky traps were deployed from 2010-2012 at multiple distances into 3-5 commercial fields, and the abundance of miner adults was counted weekly. In addition, the lower developmental threshold for the miner pupae was assessed through environmental chambers set to 10 different temperatures to inform the DD model. Asparagus miner adults were uniformly distributed throughout the field during their first generation, whereas they were primarily clustered around the edges of the field during the second generation. Adults were greatest on field edges bordered by neighboring asparagus, while the lowest abundance was found on edges bordered by forests. The lower developmental threshold for the miner was 12.1$deg;C, and DDs reliably predicted important phenological events in the life cycle of the asparagus miner when using a biofix date of March 1. These results indicate that the conservation of the remaining forested habitats may be beneficial for pest mitigation and that growers may concentrate their insecticide sprays around the edges of asparagus fields during the second generation of the asparagus miner. For the second objective, we sampled for asparagus miner pupal parasitoids from 2010-2013. There were 12 parasitic wasps that used the asparagus miner as a host. Of these, Chorebus rondanii and Thinodytes cephalon were good candidates for biological control. From rearing on artificial diets, sugar-rich resources increased both the lifespan of miner adults and its parasitoids. Rearing on various flowering plants significantly impacted the lifespan of asparagus miner adults, with buckwheat and fava bean being unfavorable resources. This research lays the groundwork for a biocontrol program. For the third objective, asparagus headspace was significantly altered both quantitatively and qualitatively, depending on damage. The main component in all headspace blends, regardless of treatment was 3E-hexenyl acetate. Asparagus miner adults significantly preferred healthy asparagus stem blends over purified air, and preferred asparagus miner-damaged blends in the presence of healthy asparagus. Finally, in the field, the asparagus miner and parasitoids were most attracted to methyl salicylate-containing baits, while other pests were most attracted to cis-3-hexen-1-ol. Consequently, these compounds should not be used in asparagus fields. Future evaluation of the volatiles identified from asparagus headspace in this study should help illuminate those with biological activity for use in an IPM program for the miner. Overall, the results from this study are expected to significantly contribute to the IPM of the asparagus miner, and give growers alternative tactics for suppressing this important pest.
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