Abiotic stress is one of the main causes of crop reduction globally. Among the different abiotic stresses, cold is an essential factor that limits crop productivity worldwide. Low temperature affects the growth, development and distribution of agronomic species throughout the world. Cold stress is a serious threat to the sustainability of crop yields. Indeed, cold stress can cause major crop losses. A significant number of researches have been reviewed and discussed in this study in order to improve the understanding of the physiological and genetic nature and function of plant cold tolerance. Recent developments in determining the mechanism of genes with roles in freezing tolerance and the systems involved in low-temperature gene regulation and signal transduction are described. The roles of a family of Arabidopsis transcription factors, the CBF/DREB1 proteins, have been described and its role in controlling the expression of a regulon of cold-induced genes (COR) that increase plant freezing tolerance has been explained. Moreover, this study has reviewed the recent application applied to improve the cold tolerance of plants such as molybdenum. The use of infrared camera to study the process of plant injuries caused by low temperature has also been reviewed.

Under cold stress, reactive oxygen species (ROS) are considered the main source of damage to plant cells. Mechanisms of ROS scavenging in wheat are very important during stress and the antioxidant enzymes superoxide dismutase, Catalase and Glutathione peroxidase are key to facilitating ROS scavenging. Molybdenum (Mo) is involved in many plant physiological and biochemical processes including antioxidant enzymes. This study reports research to investigate the effect of Mo application in enhancing antioxidant enzymes in two wheat cultivars. The results confirmed that antioxidant defense is important in wheat that is exposed to abiotic stress and that changes in activities of antioxidant enzymes occurred during exposure of plants to low non-freezing temperatures and by adding Mo. Mo application had a positive effect on gene expression of both Cbf14 and COR15a protein expression, indicating upregulation of the stress response regulon. In addition, Mo enhanced antioxidant enzymes activity and improved frost tolerance.