David Weston

David Weston

Staff Scientist


  • B.S., Cornell Univeristy, 1998
  • M.S., Cornell Univeristy, 2001
  • PhD, Clemson University, 2006

Our research is motivated by a desire to further our understanding of the underling genetics driving plant traits and metabolic processes critical to organismal performance and C cycle dynamics. Our lab takes an integrated approach using high-throughput genomic technologies, biochemistry and genetics, all placed within a physiological framework to address our research questions. Below is a brief description of our main research projects:

Plant and microbe interactions: As part of the Plant Microbes Interface project (pmi.ornl.gov), our primary objective is to understand how host plant genotype and environment interact with microbial members to shape community assembly and function. Populus spp. are known to associate with numerous microbes resulting in an assortment of functional interactions through known and yet to be discovered signaling and metabolic networks that drive neutral, antagonistic and mutualistic responses. Our efforts have identified systemic root-bacteria derived gene network that influences leaf metabolism, photosynthesis and whole plant fitness.

The SPRUCE project is a multi-year interaction among scientists at ORNL and the U.S. Forest Service at the Marcell Experimental Forest. Our objective within this large collaborative project is to define the response surface of gross photosynthesis to warming, tissue water content, and ambient CO2 concentration for dominant Sphagnum species. These results will be incorporated into peatland modeling efforts (with Paul Hanson), and plant community composition change among woody and herbaceous vegetation (with Rich Norby).

NGEE Tropics: Nutrient availability of phosphorus is increasingly recognized as a potential constraint of productivity in tropical ecosystems, potentially limiting the extent of the tropical C sink. One of the primary aims of the Next Generation Ecosystem Experiment: Tropics (NGEE Tropics) is to understand the extent to which nutrient availability is mediated by the interactions between plants and their microbiomes. Understanding the variation of plant functional traits, especially of roots, and the corresponding microbiome provides insight into the capacity to acquire phosphorus and the potential to sustain increased growth under elevated CO2. The data acquired will be used to improve ecosystem models to better predict the affects of climate change.

Ecological Genomics: The moss Sphagnum is a new study organism in our lab as it is a key member in peatland and arctic ecosystems that account for vast stores in terrestrial carbon. Whether these ecosystems continue to store carbon in response to changing climatic conditions remains an open question. This makes Sphagnum arguably the most important plant genus governing terrestrial carbon cycling. Our lab is pioneering the use of Sphagnum for ecological genomics studies and we are currently funded to generate a neutron-based mutagenesis population, a QTL mapping pedigree, and conduct RNA-Seq and physiological investigations.

The SPRUCE site at Marcell Experimental Station (MN, USA) (hi-res image)

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