U.S. Department of Energy, Office of Science

Program for Ecosystem Research

Research Project   Genomic regulation of the response of an agroecosystem to elements of global change

Principal investigator:   Evan H. DeLucia

Project goal

To integrate genomic, metabolomic, and ecologic experimental approaches to improve understanding and prediction of the potential effects of global environmental change on the functioning of a model agroecosystem. This integration of approaches is novel and potentially powerful, allowing links to be made among environmental change, gene expression, plant physiology, and ecosystem processes.

U.S. Soybean acerage

Ecosystem being studied

Soybean crop in central Illinois. The ecosystem is being studied both for its value as a crop and as a model ecosystem.

Results

Initial results indicate that growth under elevated atmospheric carbon dioxide concentration causes widespread changes in gene expression and the profile of metabolites in soybean leaves. In addition to directly affecting crop growth, increased expression of genes regulating phenylpropanoid and carbohydrate metabolism might alter plant-insect and plant-microbe interactions, both of which can be important to ecosystem-scale processes such as primary production and biogeochemical cycling.

Why this is important

Elevated atmospheric concentrations of carbon dioxide and ozone, important elements of global environmental change, are likely to affect the capacity of ecosystems to provide essential goods and services, including food, fiber, fresh water, and clean air. This research project will enhance our ability to accurately forecast the responses of terrestrial ecosystems to multiple, interactive changes in the environment.

With respect to this particular crop, soybean occupied more than 26 million hectares in the United States during 2007, or about 3.5% of the 760 million hectares of land in the 48 conterminous states. The value of the 2007 U.S. soybean crop was over $26 billion (see www.nass.usda.gov); for comparison, the 2007 U.S. gross domestic product was about $13,843 billion (see www.bea.gov). Any effects of future changes in atmospheric composition on soybean yield would therefore have important economic implications.

A SoyFACE experimental plot

An early season plot in the SoyFACE experiment.

Methods

The project is using the University of Illinois SoyFACE experimental facility to expose a soybean crop to controlled, elevated concentrations of carbon dioxide and ozone.

Congruent measurements are being conducted to interrelate gene expression, metabolite profiles, whole plant physiology and growth, and ecosystem nutrient cycles in the experimenmtal plots. Because of the broad reach of this research, from genes to ecosystem, the focus is on molecular or cellular processes that translate directly and visibly to ecosystem metabolism and nutrient cycling. These keystone processes are captured by the following two questions: Do combinations of elevated carbon dioxide, elevated ozone, and increasing drought induce cross protection or act multiplicatively to reduce ecosystem metabolism? Do environmentally or biotically induced changes in plant chemistry propagate through the ecosystem by altering nutrient cycling and susceptibility to further assault by insects and pathogens?

Personnel

M.R. Berenbaum, University of Illinois

H.J. Bohnert, University of Illinois

S.J. Clough, USDA Agricultural Research Service (unfunded collaborator)

Evan H. DeLucia, University of Illinois

R.D. Fitzhugh, University of Illinois

S.P. Long, University of Illinois

D.R. Ort, USDA Agricultural Research Service (unfunded collaborator)

Funding period:   July 2004 to present