Response of Scotorythra Caterpillars (Geometridae) to Drought Simulation and Nutrient Augmentation of Koa (Fabaceae: Acacia koa)

Simple item page
dc.contributor.advisor Haines, William P.
dc.contributor.author Chi, Megan
dc.contributor.department Biology
dc.date.accessioned 2018-06-28T19:42:01Z
dc.date.available 2018-06-28T19:42:01Z
dc.date.issued 2015-05
dc.description.abstract This study explored the plant stress hypothesis and the plant vigor hypothesis, two opposing hypotheses regarding how bottom-up factors affect herbivores. Our objective was to provide insight into whether drought may contribute to outbreaks of the specialist koa looper moth (Scotorythra paludicola), which is endemic to Hawaiʻi and causes mass defoliation of the important native koa tree (Acacia koa). However, due to the low abundance of koa moths at field sites at the time of the experiment, we used an endemic generalist Scotorythra rara, which is very closely related to the koa moth, to test caterpillar performance on water-stressed or nutrientenriched potted koa. We found no evidence that drought simulation affected phyllode characteristics. Despite this, caterpillar performance was significantly poorer on drought-stressed koa, supporting the plant vigor hypothesis. Caterpillars subjected to drought-stressed koa took longer to develop, and had lower pupal weights than caterpillars reared on unstressed koa. Furthermore, caterpillar performance was correlated with variation in phyllode physical and nutritional traits. Caterpillars performed better on phyllodes with higher water content, higher nitrogen content, lower thickness, and lower toughness.
dc.description.degree Biology
dc.format.extent 61 pages
dc.identifier.uri http://hdl.handle.net/10125/56517
dc.publisher University of Hawaii at Manoa
dc.rights All UHM Honors Projects are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission from the copyright owner.
dc.subject Scotorythra paludicola
dc.subject Scotorythra rara
dc.subject insect outbreaks
dc.subject plant stress hypothesis
dc.subject plant vigor hypothesis
dc.subject forest pests
dc.subject no choice assay
dc.subject tropical ecosystems
dc.subject Pacific islands
dc.title Response of Scotorythra Caterpillars (Geometridae) to Drought Simulation and Nutrient Augmentation of Koa (Fabaceae: Acacia koa)
dc.type.dcmi Text
Files
Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
Chi_Megan.pdf
Size:
2.47 MB
Format:
Adobe Portable Document Format
Description:
Download
Collections
Honors Projects for Biology