Risk Assessment of Transgenic Plants: Evaluation of Border Rows as a Containment Strategy for Transgenic Pollen and a Comparison of Pollen Dispersal Patterns for Native and Transgenes

Loading...
Thumbnail Image

View/Download File

Persistent link to this item

Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Risk Assessment of Transgenic Plants: Evaluation of Border Rows as a Containment Strategy for Transgenic Pollen and a Comparison of Pollen Dispersal Patterns for Native and Transgenes

Published Date

1995

Publisher

Type

Thesis or Dissertation

Abstract

Despite full commercial approval of twelve transgenic crops in the U.S. (circa 1995), concern is still being expressed regarding the potential risks associated with the agronomic-scale production of transgenic crops. One commonly mentioned concern involves the pollen-mediated escape of engineered genes into populations of crop wild relatives. In this study two questions relevant to this issue were investigated: 1) Can plantings of border rows effectively limit pollen mediated gene movement, and 2) Do the pollen-mediated dispersal patterns of transgenes differ from those of native genes? The ratio of recessive trap plants to wild type donor plants was varied to test the efficacy of border rows as a means to limit the spread of transgenic pollen to discontiguous satellite plots. Gene movement within the border plots assumed a leptokurtic distribution. Increasing the number of donor plants increased levels of gene flow both within the border and to the discontiguous satellite plots. As the trap/donor ratio increased, there was a significant decrease in long distance gene movement to the satellites, although the observed year to year and site to site variability could limit the effectiveness of this strategy. Furthermore, extremely large numbers of border plants would be required to minimize pollen movement on a commercial scale. Dispersal patterns of transgenes and native genes were evaluated by comparing levels of pollen-mediated gene movement from melon plants (Cucumis melo) expressing dominant morphological and transgenic marker genes into a surrounding border of recessive non-transgenic melon plants. Long distance dispersal patterns for the two genes were identical and dispersal patterns into the plot borders were nearly identical. Several of the apparent discrepancies were explained by transgene inactivation, a phenomenon which has implications for any study measuring gene movement with transgenic plants. Results from this study validate the assumption that native and transgenes have the same dispersal patterns. Thus, application of non-transgenic results to trans gene escape and dispersal issues should be appropriate. However, the assessment of establishment and spread will depend on both pollen movement and the fitness value of the particular transgene crop combination.

Keywords

Description

Dissertation completed at the Michigan State University, 1995

Related to

Replaces

License

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Hokanson, Stan C.. (1995). Risk Assessment of Transgenic Plants: Evaluation of Border Rows as a Containment Strategy for Transgenic Pollen and a Comparison of Pollen Dispersal Patterns for Native and Transgenes. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/162865.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.