Objective By analyzing the phenotypic traits of Syringa, the authors aim to clarify the diversity and variation characteristics of phenotypic traits in Syringa germplasm resources, provide a theoretical basis for the breeding of ornamental traits and new varieties of Syringa plants.

Methods Using 74 germplasm resources of Syringa plants as the research object, 24 phenotypic traits were selected for correlation analysis, principal component and Q-type clustering analysis.

Results 74 germplasm resources of Syringa plants exhibit rich phenotypic diversity, with a wide range of variations in flower color, corolla tube color, and leaf color traits; Correlation analysis shows that there are varying degrees of correlation between various quantitative traits, and most of them have significant or extremely significant positive correlations. Based on systematic clustering analysis, 74 Syringa germplasm resources were divided into three major groups. The first category includes 7 species, characterized by large leaves, long petioles, large flower diameters, long inflorescences, and a high number of small flowers; The second category includes 28 species, characterized by small leaves and small flower diameter; The third category includes 39 species, which are mainly characterized by multiple double petals and the least amount of small flowers;Principal component analysis shows that the cumulative contribution rate of the first 9 principal components reaches 81.27%. According to the comprehensive score of principal components, at the top of Syringa, such as Syringa vulgaris ‘Sensation’ have the best comprehensive performance.

Conclusion By analyzing the phenotypic traits of 74 germplasm of Syringa plants, it was found that there are abundant types of variation in Syringa plant traits, and different phenotypic traits can be selected for breeding and new variety selection according to breeding requirements and needs.