Davis Lab

Gerald Tuskan

Oak Ridge National Laboratory

John Davis

University of Florida

Stephen DiFazio

West Virginia University

Lee Gunter

Oak Ridge National Laboratory

Matias Kirst

University of Florida

Udaya Kalluri

Oak Ridge National Laboratory

Maude Hinchee

ArborGen

Don Kaczmarek

ArborGen

Alison Morse

University of Florida

Tim Tschaplinski

Oak Ridge National Laboratory

Tongming Yin

Oak Ridge National Laboratory

Wilfred Vermerris

University of Florida

Agency: Department of Energy

$4,084,481.00

3 years (2/1/07 - 1/31/10)

Project Overview: The fate of carbon below ground is likely to be a major factor determining the success of carbon sequestration strategies involving plants. Soil accounts for the greatest proportion of carbon stored in terrestrial systems, totaling more than plant and atmospheric sources combined. Despite their importance, belowground processes are poorly understood and basic research is needed on the processes controlling belowground carbon allocation and partitioning. Relevant processes to consider in the context of carbon sequestration include (1) the allocation of carbon to structural, coarse, and fine roots, (2) the partitioning of carbon into various pools within the cell walls of roots, and ultimately (3) the deposition of carbon into long-term soil pools. We are seeking to enhance carbon allocation to roots by altering the activity of genes involved in sucrose metabolism, thereby stimulating belowground carbon transport and root proliferation. We have targeted genes involved in the auxin and cytokinin pathways, because these growth regulators have strong, interacting effects on root proliferation and development. And, we are in the process of identifying novel genes that control carbon allocation and partitioning in poplar.

Davis Lab Role: Our role is to enhance carbon allocation and partitioning to roots by altering the cytokinin signaling pathway. Cytokinins are growth regulators produced in roots and regulate cell division, tissue differentiation, the release of buds from apical dominance and senescence.  Transgenic trees, altered in their expression profiles of candidate genes in the cytokinin signaling pathway, will be made at Arborgen and returned to the Davis Lab for characterization. Extensive morphological, physiological, biochemical and molecular phenotyping of these transgenic trees will be carried out using various techniques such as whole plant growth measurements, measurement of photosynthetic and respiratory rates, pyrolysis-gas chromatography mass spectrometry and whole genome microarrays.