Ethan Thibault
Year: 2016
Faculty Advisor: Maria Harrison

Investigation into Root Colonization of Wild Rice and Brachypodium distachyon by Arbuscular Mycorrhizal Fungi

Project Summary

With an increasingly desperate demand for food and renewable energy, researchers are interested in producing higher yields in agronomic and biofuel plants like rice, wheat, barley, Miscanthus, switchgrass, and Prairie Cordgrass. Arbuscular Mycorrhizal Fungi (AMF) are symbiotic organisms that penetrate the roots of all of these plants and colonize their cortical cells. At these colonization interfaces the fungi provide the plant with nutrients like phosphate and nitrogen from the surrounding soil, while the plant provides the fungus with carbon for its growth. Colonization typically leads to increased tiller production, biomass, and yield. Understanding how AMF enter and move through root cells is crucial to maximizing colonization, which can lead to less fertilizer application, increased yield/biomass in agronomic and biofuel plants, and the ability to grow them on marginal lands. To do this, we are inoculating 17 inbred accession lines of Brachypodium distachyon and 8 lines of wild rice with AMF. Based on the known phenotypic variation within these groups, we expect differences in the amount of colonization and the patterns of infection. Expected changes in gene expression from line to line will lend insight into the mechanisms of colonization as well. We are also creating CRISPR knockouts of multiple candidate cell wall proteins that are upregulated during symbiosis with the fungi. These same genes and their promoters are being tagged with GFP to identify subcellular localization and monitor expression patterns respectively. We expect this to yield insight into how the root cell walls remodel to accommodate the growing fungi.

My Experience

It has been an incredible two months here at BTI. I have learned so many new lab techniques like cloning, bacterial transformations, primer construction and more. I was able to explore the molecular aspects of plant biology in a way that I couldn’t before and I was able to take part in a professional research environment with individuals at different stages of their career. They offered insight into what to expect in graduate school and as a postdoctoral researcher. It was also great being able to explore Cornell University, knowing that I want to apply here for graduate school, and also knowing that I could come to BTI for my graduate degree. Finally, the best part about partaking in this experience, for me, was to be completely surrounded by other researchers who are just as passionate as I am about plant biology and the potential for plant research.