Dissertation Research: Variation in the effects of mycorrhizal fungi on plant resistance to herbivores

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

Intellectual merit: Nearly all biological organisms form partnerships with other species in which they trade resources or services: such partnerships are called mutualisms. Mutualisms incur costs as well as provide benefits to the organisms involved and the net outcome of the partnerships can vary from positive (mutualistic) to negative (parasitic). Quantifying the costs and benefits of resource exchange within mutualisms is required to predict shifts in the outcome of these interactions under a range of environmental conditions. One of the most common mutualisms on earth occurs between the roots of plants and certain fungi that live in soil. The fungi provide essential nutrients to plants, such as phosphorus and nitrogen, while plants provide the fungi with sugars in return. As these resources are traded, it can influence other organisms in the environment, such as the insects that feed on plants. At present, scientists are unable to predict how the outcome of plant-fungal partnerships will vary with the identity and abundance of the fungi in soil and the genetics of the plants. The proposed work will manipulate the identity and abundance of the partners in plant-fungus mutualisms and measure how resources are traded between them. By studying how well the partners perform, the project will help scientists understand how partnerships form and dissolve in nature. Broader impacts: Scientists have yet to develop realistic theories of how mutualisms work, despite the fact that they are extremely common in nature. Results from this work will be broadly applied by ecologists and evolutionary biologists who work on many different kinds of organisms throughout the world. Moreover, results gained from studying mutualisms between plants and fungi can be used in a wide variety of human endeavors including agricultural and forest production, the restoration of degraded environments, the prediction and management of environmental change, and the management of invasive species. Additionally, mutualistic partnerships in nature are mimics of economic partnerships among human institutions in which goods and services are traded, and the results will apply across human and natural systems. During the work described here, scientists from a range of social and ethnic backgrounds will be trained in the methods of science. Finally, results from this work will be transmitted to local, national and international audiences through publications and presentations.