Cold stress in Brassica vegetables: Morpho-physiological and molecular responses underlying adaptive mechanism

Brassica vegetables are cultivated worldwide and commonly experience cold stress. Cold stress hampers the production of Brassica vegetables through several morphological, physiological, and molecular changes. Brassica plants adapt to these alterations by regulating their physiological and molecular behavior. Physiologically, cold stress leads to decreased antioxidant enzyme activities and increased ROS damage. Moreover, various molecular pathways are also regulated under cold stress and regulate cold-responsive genes, including COR, inducer of CBF expression 1 (ICE1), and several transcription factors, including bZIP, HOS9, SCOF1, and WRKY. Furthermore, the CBF and COR genes also regulate dehydration-responsive elements (CRT and DRE) and play a significant role in Brassica cold tolerance. Our review emphasizes recent explorations and identifies knowledge gaps about how Brassica vegetables react to cold stress. This review provides an integrative view of the morphological, molecular, physiological, genetic, and genomic aspects of cold stress in Brassica vegetables and could be valuable for future research programs in understanding cold stress resilience in Brassica vegetables.