Plants initiate interactions with soil microbiota through root exudation. Thus, manipulating root exudation of plants presents a unique opportunity to influence soil microbial communities in a manner that will ultimately benefit plant/crop health. This project will provide such tools by characterizing a mutant (Atpdr2) of the model plant Arabidopsis thaliana coding for an ATP-binding cassette (ABC) transporter in which the ratio of sugars to secondary metabolites in the root exudates is altered compared to the wild-type (wt). We found that when Atpdr2 is grown in native Arabidopsis soils, a complete overhaul of the microbial community compared with wild-type Arabidopsis roots is seen. The Atpdr2 mutant promotes the growth of beneficial bacteria, such as plant growth and promoting rhizobacteria (PGPRs), nitrogen fixers and bacteria involved in heavy metal remediation. First, the project will address the influence of root-secreted chemical compounds and families from Atpdr2 and wt plants on the growth of beneficial soil microbes within the native microbial community. The second objective of the project is to characterize the Atpdr2 mutant to determine mechanisms used by the mutant to alter the ratio of sugars and secondary metabolites exuded by roots. These studies are transformative because they will provide mechanistic knowledge to develop new approaches by which crops can be genetically manipulated to culture soil microbes for beneficial purposes.
Broader Impacts:
This project will provide training for undergraduate and graduate students, and a post-doctoral trainee in research activities. These activities will be complemented with career development and mentoring workshops particularly targeted to graduate students and postdocs. In addition, the project will provide summer research and training activities for minority undergraduate students from the John Jay College of Criminal Justice of the City University of New York and educational activities for elementary students in Fort Collins. In the third year of the project, a colloquium will be conducted to discuss science, energy issues, third-world country involvement in energy topics, intellectual property, and international treaties related to microbial diversity.