"Asparagus production in Michigan is limited in longevity, productivity, and market value by two key monophagous insect pests, the asparagus miner (Ophiomyia simplex Loew) (Diptera: Agromyzidae) and common asparagus beetle (Crioceris asparagi L.) (Coleoptera: Chrysomelidae). Asparagus producers have expressed interest in pursuing the development of biological control management tactics because the current chemical management tactics available are ineffective at controlling these pests. My research seeks to fill knowledge gaps that currently exist in our understanding in biological control tactics for these pests by: 1) establishing pest and natural enemy spatial distributions, 2) developing a molecular gut content analysis protocol for predators of the two pests, 3) determining key predators of these two pests, 4) investigating the influence border habitats have on predator abundance, 5) identifying herbivore induced volatiles of asparagus, 6) determining natural enemy and pest attraction to asparagus volatiles, 7) examining the attraction of volatile lures to pests and natural enemies in a field setting, and 8) investigating the use of volatile lures to increase biological control of the two key pests. Pests and predator arthropods were collected from transects inside fields, on the field edges, or in margin habitats, weekly in 2014 and 2015, from commercial asparagus fields with different border habitat types. Key asparagus pests had significantly higher abundances on the field edge, while predator arthropods were found in higher abundance in the field margin. Key pests had higher abundances in fields bordered by another asparagus field, while predators were found in higher abundance in fields bordered by forests. Molecular gut content analysis revealed predators testing positive for the DNA of either key pest were primarily collected from field margins with forested habitats or margins planted with other (non-asparagus) crops. In 2014, headspace was collected from asparagus grown in field cages that were exposed to either no damage, mechanical damage, or feeding damage from the common asparagus beetle. I found that asparagus responds to specialist herbivory through upregulation in the production of (E)-b-ocimene, (E,E)-a-farnesene, and 1-tetradecanol. In 2015 and 2016, y-tube olfactometer tests revealed that adult asparagus beetles and predatory lady beetles had little attraction to asparagus volatiles. In 2016, field lures were developed from induced asparagus volatiles and tested in commercial fields; all attracted significantly more parasitoids than control lures but did not attract predators or pests. In 2017, the most attractive lure to parasitoids identified in the previous year's research was deployed in an effort to increase the biological control of key pests by parasitoids using two lure deployment densities. It was determined that lures deployed in a low-density arrangement led to increases in the number of asparagus miners attacked by individuals from the Pteromalidae parasitoid family. Overall, the results of this research offer the most comprehensive attempt, to date, to develop a biological pest control tactic in asparagus and represents a promising avenue for future pest management research in this specialty crop."--Pages ii-iii.
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