Grantee Research Project Results
Potential Impacts of Transgenic Poplar CultivationEPA Grant Number: U915226
Title: Potential Impacts of Transgenic Poplar Cultivation
Investigators: DiFazio, Stephen P.
Institution: Oregon State University
EPA Project Officer: Smith, Bernice
Project Period: October 1, 1997 through October 1, 2000
Project Amount: $102,000
RFA: STAR Graduate Fellowships (1997)
Research Category: Fellowship - Forestry , Academic Fellowships , Biology/Life Sciences , Ecological Indicators/Assessment/Restoration
The main goal of this research project is to determine potential environmental impacts of widespread cultivation of genetically engineered hybrid poplar (Populus spp.) trees. The specific objectives of this research project are to: (1) determine current levels of gene exchange between poplar plantations and wild stands; (2) characterize establishment of hybrid poplars; (3) simulate potential spread of transgenic trees; and (4) evaluate potential impacts.Approach:
I am developing two tools critical to risk assessment of transgenic trees: (1) hypervariable DNA markers for monitoring gene flow and paternity; and (2) spatially explicit computer models of gene dispersal over the landscape. To predict gene flow from hybrid plantations, it is necessary to understand both the dynamics of gene movement within and between populations and the ability of hybrid trees to produce fit progeny. I will study dynamics of gene movement in two wild poplar stands, and will analyze hybrid fitness and gene dispersal adjacent to flowering plantations in western Oregon. For both studies, I will use highly polymorphic DNA markers (random amplified polymorphic DNA and simple sequence repeats) and paternity analysis. I also will study dispersal and competitive ability of hybrids in the vicinity of existing plantations by surveying regeneration under natural conditions and in artificially disturbed plots. Using data from these gene flow studies, remote sensing databases, and the literature, I will develop a spatially explicit computer model, and will use it to simulate transgene spread from plantations in two regions in the Pacific Northwest. The model will be used to identify the genetic and ecological parameters most critical to predicting the spread of herbicide and insect resistance transgenes over space and time.Supplemental Keywords:
fellowship, gene flow, genetic engineering, simulation model, tree, poplar.