Coronatine alleviates cold stress by improving growth and modulating antioxidative defense system in rice (Oryza sativa L.) seedlings

Low temperature represents a key environmental stress adversely affects rice growth and productivity worldwide. The application of cold resistance regulators is an effective way to enhance crop cold tolerance and yields. Coronatine (COR), a structural and functional analog of JA, plays a crucial role in plant stress response. In order to investigate the role of COR in alleviating cold stress of rice, the cold-resistant variety Nipponbare and cold-sensitive variety Guichao2 were used to study. The results indicated that 0.01 mu mol L-1 COR possessed the most favorable cold resistance potential. Under cold stress conditions, 0.01 mu mol L-1 COR treatment promoted the germination of rice seeds, increased the accumulation of osmotic adjustment protective substances, and mitigated the toxic effect of reactive oxygen species on cells. Additionally, COR induced the expression of cold-responsive genes, including OsCBF1, OsCBF2, OsCBF3 and OsMYB2. Overall, COR regulated the antioxidative defense system and CBF genes expression of rice to withstand cold stress.