DISSERTATION RESEARCH: The effect of plant phylogenetic and chemical diversity on herbivore community structure and plant host herbivore damage

University Of Missouri-Saint Louis, Saint Louis MO

Investigators

Abstract

One of the great challenges for ecologists is to find general rules that apply to all or most ecosystems throughout the world. One such rule that seems to be universally true is that simplification of natural plant diversity to single species plantings, such as occurs in agriculture and forest plantations, leads to high vulnerability of the plantings to pest insect outbreaks. Insects can better find their food plants, and there is more food available in single species plantings than in more diverse vegetation. The goal of this study is to more clearly understand the factors that contribute to vulnerability of simplified ecosystems. Three components are likely to be important: the number of plant species, the evolutionary relatedness of the species, and finally, differences in plant traits that influence attack by insects that are unique to each plant species. The goal of this study is to test the effect of these intrinsic plant differences on patterns of damage caused by insects by creating field experimental plant communities with different evolutionary and chemical intrinsic differences. The study will take place in a tropical wet forest site in Costa Rica using plant species related to the source of the spice black pepper. This study will not only render valuable insight into how biodiversity can affect natural ecosystems, but also enrich our knowledge of plant-herbivore systems so that we can develop novel ways to manage conventional and organic agricultural practices. In addition, because related plant species to those being studied are known to produce chemicals with insecticidal properties that have been used successfully against agricultural pests, the study may discover new compounds of similar value for the control of such insects. This project will also provide an opportunity to collaborate and train undergraduate students from the University of Costa Rica and the Organization for Tropical Studies. Furthermore, the laboratory component of this project that will be carried out at the University of Missouri-St. Louis, will allow two undergraduate students from the university to participate on all aspects of the chemical analysis. This will allow the students to obtain "hands on" research experience.