Jasmonic acid enhances aluminum tolerance of rice by regulating detoxification genes.

Aluminum (Al) stress in acidified soils represents a critical limitation for rice productivity and sustainable cropping. Jasmonic acid (JA) plays a crucial role in plant responses to Al stress, yet its underlying molecular mechanisms remain poorly understood. This study aimed to elucidate the role and mechanisms of JA in mitigating Al toxicity in rice. We found that Al stress upregulates the expression of the genes associated with JA biosynthesis in rice roots, leading to elevated endogenous JA levels, implying its involvement in Al stress responses. Exogenous JA application significantly reduced Al accumulation in root tips and alleviated Al-induced root growth inhibition. Mechanistically, JA upregulated the expression of the transcription factor OsWRKY22 (WRKY GENE 22), citrate transporter genes OsFRDL4 and OsFRDL2 (FRD3-LIKE PROTEIN 2/4), and the Al-binding protein gene OsCDT3 (CADMIUM TOLERANCE 3), thereby preventing the entrance of the Al into the cytoplasm. Furthermore, JA increased nitric oxide (NO) levels in root tips, alleviating root growth inhibition. These findings demonstrate that JA mitigates Al toxicity through enhancing NO-mediated stress tolerance and restricting Al uptake, providing new insights into the molecular basis of JA-mediated Al resistance in rice.