Dissertation Research: The Effects of Elevated CO2 on Plants, Pathogens, Herbivores, and Natural Enemies: Ecological Consequences and Evolutionary Potentials

Western Michigan University, Kalamazoo MI

Investigators

Abstract

DDIG - DEB-010509 The Effects of Increasing Atmospheric CO2 on Plant Defense Against Pathogens When grown under elevated carbon dioxide, plant leaves typically contain lower concentrations of nitrogen. Because plant defenses against herbivores and pathogens are nitrogen-intensive, rising atmospheric CO2 may make it more difficult for plants to mount an effective defense against pathogens, particularly if they are required to defend themselves against an herbivore at the same time. I will expose turnip grown under current and twice current levels of CO2 to a bacterial pathogen, and measure levels of both salicylic acid (a signal molecule in pathogen response) and anti-pathogen proteins. I will also simultaneously expose a subset of plants to simulated herbivory, and measure levels of protease inhibitors (a nitrogen-rich anti-herbivore defense). Together, these experiments will allow me to determine whether there is a trade-off between defense against pathogens and against herbivores, and whether this trade-off will become more severe as atmospheric CO2 continues to rise.