Submitted to: Abstract of International Horticultural Congress
Publication Type: Abstract Only
Publication Acceptance Date: April 1, 2002
Publication Date: June 21, 2002
Citation: WISNIEWSKI, M.E., FULLER, M., GLENN, D.M., DUMAN, J. USING INFRARED THERMOGRAPHY TO STUDY ICE NUCLEATION AND PROPAGATION IN PLANTS. ABSTRACT OF INTERNATIONAL HORTICULTURAL CONGRESS. 2002. Technical Abstract: Infrared thermography has provided new details about the freezing process in most of the plant species in which it has been used. It offers a distinct advantage over other methods of studying ice nucleation and propagation, in that it allows one to directly visualize the freezing process. This is done in a non-intrusive manner which overcomes any influence of attached objects, such as thermocouples, on the pattern of freezing. As a result of a number of studies, several new possibilities for providing an externally-applied, hydrophobic barrier, may provide a way of blocking extrinsic ice formation from propagating into a plant and initiating a freezing event. In particular, the application of a hydrophobic particle film to the surface of tomato plants has provided frost protection and prevented tomato plants from freezing despite the presence of ice on the external leaf surface. Selecting for the presence of barriers to ice propagation in woody plants that allow expanded flowers or inflorescences to supercool despite the formation of ice in stem tissues, may also be a practical approach for enhancing cold hardiness during spring frosts. We have also obtained evidence that the expression of transgenes coding for insect antifreeze proteins in transgenic Arabidopsis can enhance supercooling in plants in the absence of extrinsic ice nucleation. Examples of the factors involved in ice nucleation and propagation in plants, as observed with infrared thermography, will be presented along with recent applications of this technology.