<p> As herbivorous insects choose where to lay their eggs, maximizing larval performance (optimal oviposition) may be at odds with adult foraging (optimal foraging). Aspen leaf miners (<i>Phyllocnistis populiella</i>; ALM) may choose between leaves with or without extrafloral nectaries (EFNs) as oviposition sites on quaking aspen (<i>Populus tremuloides</i> Michx.). Reduced ALM mining on leaves with EFNs may be linked to predators that defend leaves and feed at EFNs, and to increased concentrations of secondary leaf compounds. However, direct responses of adult ALM to EFN expression may also explain differences in ALM mining among leaves with and without EFNs. ALM might be less likely to oviposit on leaves with EFNs because these leaves provide poor conditions for larval development. With choice experiments and surveys of ALM oviposition, we examined oviposition site preference in relation to EFN expression. In choice experiments and field surveys adults preferred to oviposit on leaves without EFNs. Increased oviposition was also observed on shoots with high EFN frequencies, suggesting a combination of optimal foraging and optimal oviposition, and a role of EFNs at scales above the leaf level. Higher predation on leaves with EFNs likely exerts selective pressure for the observed ALM oviposition preference for non-EFN leaves.</p>
| Identifer | oai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:1551924 |
| Date | 04 March 2014 |
| Creators | Dennis, Russell E. |
| Publisher | University of Alaska Fairbanks |
| Source Sets | ProQuest.com |
| Language | English |
| Detected Language | English |
| Type | thesis |
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