Co-PI: Sue M. Hum-Musser (Western Illinois University)
Collaborator: Heiko Vogel (Max Planck Institute for Chemical Ecology, Jena, Germany)
Insect herbivory dramatically affects how plants defend themselves against insect feeding, pathogen infection, as well as plant growth habits. Plants respond differently when fed on by insects compared to mere physical wounding. This response is likely due to saliva produced and secreted by the insect. The complexity of plant defense pathways still need to be determined due to interactions between the two major plant defense mechanisms that can be stimulated by herbivores with different methods of feeding. Chewing insects produce large wounds and sucking insects produce smaller punctures in the plant tissue. In addition, the success of plant feeding insects is dependent on their ability to overcome plant produced toxic compounds. This project will investigate the role of caterpillar saliva and aphid secretions simultaneously stimulating the corn and tomato plant defense responses using microarray hybridization technology. To date, there have been few studies of this kind investigating the simultaneous feeding of two different types of plant herbivory that are known to stimulate the opposite and different plant defense pathways, compared to feeding from a single type of insect. Through an international collaboration with scientists at the Max Planck Institute for Chemical Ecology (Germany), the project will concurrently address how the insect herbivore responds to consumption of toxic plant defense compounds and defensive proteins. These experiments may reveal any connection between plant defense compounds in response to insect herbivory and the insect defense responses to plant defensive chemicals. Because insect pests cause billions of dollars of damage to U.S. agriculture annually, information from this project could provide new insight required to develop novel methods for protecting economically important plants.
This project will be performed by an international team of researchers and undergraduate and graduate students at Western Illinois University. Students will be trained and work in all phases of the scientific process that will provide an invaluable research experience that will prepare them for their future as scientists and researchers. Knowledge of these important plant and insect interaction and defense pathways will be disseminated to the general public and scientific communities through scientific meetings and papers, regular course offerings at the University where the project is being run, yearly workshops for students and high school teachers, and general public news communications. In addition, all data will be available through the project website and through Gene Expression Omnibus (GEO) (www.ncbi.nlm.nih.gov/projects/geo/). All biological materials used are available through general seed companies and insectaries.