Presenter: Mason Hoffman
Authors: Mason Hoffman
Faculty Advisor: Michael Rotter
Institution: Utah Valley University
The ability of non-native plants to successfully invade and dominate ecological communities is a central area of ecological study. Many important hypotheses such as the evolution of increased competitive ability and the novel weapons hypothesis suggest that the reason for non-native success is the ability of non-native plants to have reduced herbivory burdens, allowing them a competitive advantage over native plants that are attacked by insect herbivores. The insects that “choose” the “winners and losers” of plant-plant interactions are also dealing with their own antagonistic relationships, particularly parasitoid predators. Many herbivores have been found to deal with these parasitoids by medicating themselves through their diets. We tested to see if this medication may help explain herbivore preference for native or non-native plant species by testing the immune responses and survivability ofTrichoplusia nifed on the nativeMimulus guttatusand the non-nativeNasturtium officinale.Immune responses of 5th starT. niwere elevated while feeding on N. officionale compared to those feeding onM. guttatus. Further, we found thatT. nineonates were not able to survive onN. officionalewhile neonates survived onM. guttatus.Our results suggest that herbivores may alter plant-plant competition when they are faced with their own top-down pressures, while still having significant restraints on their ability to consume n