Genomics of Cold Hardiness in Woody Plants

The term cold hardiness or freezing tolerance is used to represent, in a general sense, the ability of plants to adapt to and withstand freezing temperatures. It is a complex, multigenic trait that is too often viewed as a single entity when in fact it is composed of many aspects, all of which can be to some extent viewed as genetically distinct. Advances in molecular biology and genomics have provided significant advances in understanding how plants respond to low temperature and acquire freezing tolerance. Among the most important discoveries has been the identification of the CBF/DREB transcription factor. This transcription factor, along with its regulators such as ICE transcription factors, play a major role in sensing low temperature, initiating the process of cold acclimation, and inducing the expression of a large set of cold-regulated genes. These latter genes are presumed to ameliorate injury to plant cells as a result of freeze-induced desiccation and the presence of extracellular ice. The pres...