Book excerpt: Low-temperature stress is the primary abiotic stress that affects the growth and development of plants and their geographical distribution. This can lead to the solidification of membrane lipids and decrease of enzymatic reaction rate in plants in a relatively short time, or indirectly affect the imbalance of respiration and photosynthesis, accumulation of toxic substances, ATP depletion, cell solute leakage and wilting due to water loss. Low-temperature stress can be divided into chilling stress and freezing stress according to the damage caused to plants. Both chilling and freezing stress drastically threaten global food security and species diversity in the northern and frigid temperate zones. Once plants experience low-temperature stress, the regulation mechanism of gene expression is rapidly activated to cope with the adverse environment.