|NEUNER, GILBERT - University Of Innsbruck|
|GUSTA, LAWRENCE - University Of Saskatchewan|
Submitted to: Journal of Visualized Experiments
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/12/2015
Publication Date: 2/20/2015
Citation: Wisniewski, M.E., Neuner, G., Gusta, L.V. 2015. The use of high-resolution infrared thermography (HRIT) for the study of ice nucleation and ice propagation in plants. Journal of Visualized Experiments. DOI: 10.3791/52703.
Interpretive Summary: Frost events in the spring can have a devastating effect on plants causing significant injury to fruit and vegetable crops, as well as plants grown for the nursery industry. These frost events can result in severe economic losses to farmers and higher food prices for consumers. Frost events can also play a role in determining what plants live and die in natural populations of plants, especially in alpine, sub-arctic, and arctic ecosystems. Some plants have the ability to avoid freezing and escape injury by a process called supercooling. Studying and documenting the freezing process in plants has been difficult and usually relies on indirect measurements that reflect freezing events but mask the complexity of the freezing process in plants. In this report, USDA-ARS researchers, in collaboration with scientists from two international universities, have demonstrated the ability of high-resolution infrared thermography (HRIT) to observe, visualize, and document the freezing process in plants. This technology can be used to gain a wealth of information on how, when, and where ice forms and propagates in plants. This report documents the approach and demonstrates its utility. Since it includes a video demonstration of the protocol, the report can serve as an educational tool for USDA-ARS researchers and other scientists developing frost protection strategies, as well as students interested in low-temperature science.
Technical Abstract: Freezing events that occur when plants are actively growing can be a lethal event particularly if the plant has no freezing tolerance. Such frost events often have devastating effects on agricultural production and can also play an important role in shaping community structure in natural populations of plants, especially in alpine, sub-arctic, and arctic ecosystems. Therefore, a better understanding of the freezing process in plants can play an important role in the development of methods of frost protection and understanding mechanisms of freeze avoidance. Here, we describe a protocol to visualize the freezing process in plants using high-resolution infrared thermography (HRIT). The use of this technology allows one to determine the primary sites of ice formation in plants, how ice propagates, and the presence of ice barriers. Furthermore, it allows one to examine the role of extrinsic and intrinsic nucleators in determining the temperature at which plants freeze and evaluate the ability of various compounds to either affect the freezing process or increase freezing tolerance. The use of HRIT allows one to visualize the many adaptations that have evolved in plants, which directly or indirectly impacts the freezing process and ultimately enables plants to survive frost events.