Abstract
Chrysanthemum × morifolium is a commercially important flower worldwide. Chrysanthemum lavandulifolium is the main model plant for the research on Chrysanthemum. Enhancing stress resistance in C. lavandulifolium is highly significant for improving commercial chrysanthemum production. NAC transcription factors are key regulators of plant growth, development, and stress responses. In this study, we cloned ClVND1-a member of the OsNAC7 subfamily within the NAC transcription factor family-from Chrysanthemum lavandulifolium. The gene comprises a 1164 bp coding sequence (CDS) encoding a protein of 387 amino acids. Overexpression of ClVND1 promotes secondary cell wall thickening in the stems of transgenic Arabidopsis, stimulates lateral root growth, and consequently enhances tolerance to salt and low-temperature stress in seedlings. Phenotypic analysis showed that transgenic Arabidopsis exhibited reduced inflorescence elongation and plant height compared to wild-type controls, but an earlier flowering time. These findings suggest that ClVND1 enhances stress resistance by promoting lateral root development, while also suppressing inflorescence growth and accelerating flowering time.