Role of Endophytic Fungi in Managed and Natural Ecosystems
Principal Investigator: Dr. Thomas Bultman
Students engaged in this research project will have an opportunity to explore how endophytic fungi impact the internal environment of plants, while testing hypotheses concerning the consequences of those impacts on plant and insect herbivore fitness. Endophytic fungi grow intercellularly within the shoots of many grasses and appear to protect the plants from insect herbivores. The mechanism of this protection is purported to be toxic alkaloids produced by the plant/fungal symbiotum. We have shown that grass endophytes mediate wound-induced resistance to insect herbivores. That is, the fungal endophytes are stimulated to provide heightened levels of protection for the plant following initial damage to the plant.
One direction of current research is to assess the molecular basis of the induced response and determine if fungal and/or plant genes are responsible for the wound-induced response. Students will assist in formulating testable hypotheses concerning the interactions among endophytes, tall fescue grasses, and insect herbivores (e.g. aphids and caterpillars). Students will design methods of testing these hypotheses while learning various molecular techniques, and methods for fungal staining and detection.
- Bultman, T.L., J.L. Rodstrom*, K.R. Radabaugh*, J.D. VanDop*, J.M. Librizzi*, L.L. Longwell*, C. Pulas*, L. Grant*, and T. J. Sullivan. 2009. Influence of genetic variation in fungal endophyte of a grass on an herbivore and its parasitoid. Entomologia Experimentalis et Applicata 130: 173-180.
- Bultman, T.L., T.J. Sullivan, M.H. Cortez, and T. Pennings. 2009. Extensions to and Modulation of Defensive Mutualism in Grass Endophytes. in press. Defensive Mutualism in Symbiotic Associations. Torres, M. and White, J.F., Jr. (Eds.). Taylor & Francis Publ.
- Simons*, L., T.L. Bultman, and T.J. Sullivan. 2008. Effects of Methyl Jasmonate and an Endophytic Fungus on Plant Resistance to Insect Herbivores. Journal of Chemical Ecology 34:1511-1517.
- Bultman, T.L. and A. Leuchtmann. 2008. Biology of the EpichloŽ-Botanophila Interaction: an Intriguing Association between Fungi and Insects. Fungal Biology Reviews 22:131-138.
- Bultman, T.L. and D.J. DeWitt*. 2008. Effect of an Invasive Ground Cover Plant on the Abundance and Diversity of a Forest Floor Spider Assemblage. Biological Invasions 10:749-756.
- Gonthier*, D.J., T.J. Sullivan, K.L. Brown, B. Wurtzel*, R. Lawal*, K. VandenOever*, Z. Buchan*, T.L. Bultman. 2008. Stroma-forming endophyte EpichloŽ glyceriae provides wound-inducible resistance to its grass host. Oikos 177:629-633.
- Sullivan, T.J., J. Rodstom*, J. Vandop*, J. Librizzi*, C. Graham*, C. L. Schardl, and T. L. Bultman. 2007. Symbiont-mediated changes in defensive strategy in the invasive grass Lolium arundinaceum: evidence from changes in gene expression and foliar elemental composition. New Phytologist. 176:673-679.
- Bultman, T.L., C. Pulas*, L. Grant*, G. Bell*, T.J. Sullivan. 2006. Effects of endophytic fungal isolate and plant cultivar on host preference by two insect herbivore species. Environmental Entomology 35:1690-1695.
- Bultman, T.L., G. Bell*, and W. Martin*. 2004. A fungal endophyte mediates reversal of wound-induced resistance and constrains tolerance in a grass. Ecology 85:679-685.
*represents undergraduate student