Component Analysis of Anthocyanins in Petals at Different Flowering Stages of Three Rosa rugosa Hybrid Cultivars

The species and contents of anthocyanins in plant petals can make plants appear pink, red, violet and blue, etc., and play a major role in the coloration of plants. In this study, the species and contents of anthocyanins in the petals of three R. rugosa hybrid cultivars, R. rugosa “Zizhi”, R. rugosa “Fenzizhi” and R. rugosa “Baizizhi”, were analyzed, and the direct cause of the differences in flower color of three R. rugosa hybrid cultivars was inferred. This paper provides a reference for the coloration mechanism and flower color breeding of R. rugosa. The specific methods are as follows: the petals of five flowering stages of three R. rugosa hybrid cultivars were used as materials, and the types and contents of anthocyanins contained in them were qualitatively and quantitatively analyzed by high performance liquid chromatography (HPLC). The same six kinds of anthocyanins were identified in R. rugosa “Zizhi” and R. rugosa “Fenzizhi”, mainly based on the diglycoside of paeoniflorin and cyanidin. The relative contents of the two anthocyanins were higher at budding stage and initial opening stage. In the different flowering stages of R. rugosa “Zizhi”, the content of Pn3G5G was up to 4280.84 ± 20.82 μg·g-1, and the content of Cy3G5G was up to 789.41 ± 1.21 μg·g-1. In R. rugosa “Fenzizhi”, the highest content of Pn3G5G reached 1293.50 ± 17.64 μg·g-1, and the content of Cy3G5G was up to 358.86 ± 3.94 μg·g-1. It could be speculated that the difference in the contents of Pn3G5G and Cy3G5G was the main reason for the difference in coloration between the petals of R. rugosa “Zizhi” and R. rugosa “Fenzizhi”. A total of five species of anthocyanins were identified in R. rugosa “Baizizhi” and their contents were relatively low. Compared with R. rugosa “Zizhi” and R. rugosa “Fenzizhi”, the presence of Cy3G was not detected. Therefore, we speculated that the two reasons above might be responsible for the visual white flowers of R. rugosa “Baizizhi”.