Abstract:In order to understand the function and expression patterns of the MADS-box gene family in Yulania liliiflora, based on the transcriptomic data of ‘Hongyuanbao’, the members of MIKC MADS-box gene family were identified, their physical and chemical properties, phylogenetic evolution and conserved domain were analyzed. The results showed that a total of 19 MIKC MADS-BOX gene family members were identified, all of which were located in the nucleus and shared common MADS or K-box conserved domains. Most MlMADSs played role in floral organogenesis, and MlAGL6 and MlAGL12-c might be important nodes in the protein interaction network. MlMADS-box members had high expression in stamen, flower bud and stem tissues, and play an important role in flower organ formation and flower development. The candidate key gene MlAGL6 was screened regulating the secondary flower formation of ‘Hongyuanbao’. These would provide data support for exploring the function of MIKC MADS-box gene in the reproductive development of Y. liliiflora ‘Hongyuanbao’.