Abstract:

Chilling injury is one of the ecological factors causing environmental stress in plants. Exploring the physiological and ecological mechanisms of cold tolerance in plants can understand how plants grow at low temperature, which has important meaning in theory and practice. At present, study on cold tolerance in plants focuses on physiology, genes, and relationship between plants and environment and so on. This article reviews the physiological and ecological response of plants to low temperature during cold acclimation. Overwintering plants encased in ice can be exposed to anaerobic conditions and suffer phytotoxicity. Photoinhibition induced the increase of reactive oxygen species (ROS), causing the degradation of photosystems, which is unfavorable for cold hardiness of plants. Short days induce dormancy in plants, resulting in a increase in cold hardiness of plants. Phytochrome has been considered to be the photoreceptor responsible for triggering the initiation of the first stage of cold acclimation. The accumulation of carbohydrates and pathogenesis-related proteins enhances the resistance of plants to low-temperature pathogens. Scientists predict that plants will suffer greater risk of low-temperature damage with the changes in climate. An initial partial disassembly of microtubles is sufficient to trigger efficient cold acclimation. The adaptation of plants to cold also associates with the increased levels of antioxidants enzymes, sugar, proline, polymines and so on. Changes in dormancy status are more likely related to changes in ABA sensitivity than to variations in ABA levels. The expression of COR (cold responsive) genes is critical in plants for both chilling tolerance and cold acclimation. Genotypes from colder environments have greater cold hardiness in situ than those from milder environments. The QTL analysis of multiple phenotypic traits provides the basis for marker assisted selection (MAS) of important agronomic characters. Calcium is an important second messenger in a low temperature signal transduction pathway involved in regulation of cold-acclimation response. Signal transduction, gene regulation, genetics, metabolomics, and climate change affecting the plant survival are important aspects in the future study of cold tolerance in plants.

Key words: plants, environment, cold tolerance, physiology, molecular mechanism