*2.1. Color Di*ff*erences and Quantity Distribution Pattern*

After applying quantitative statistics to the individuals with the three distinct flowers at the full bloom stage randomly distributed in three rock populations, we concluded that the rose-purple individuals account for nearly 60%, the pink ones occupied about 30%, and the white ones not more than 10% (Table 1). The ratio of the number of the three differently flowered plants (rose-purple:pink:white) is roughly 6:3:1. Thus rose-purple is the main flower color in the Huanglong population, while white is the rarest color.

**Table 1.** Number of *P. limprichtii* individuals of each flower color polymorph in three selected populations at the opening stage.


The percentage indicates the proportion of individuals with a given color account for the total number of individuals in the population.

According to principle component analysis, there were significant differences in the a\*(redness and greenness) values of the three colors (Figure 1. A comparison of L\* (lightness) and C\* (chroma) values among the three color groups indicated that C\* values can also be used as an indicator to distinguish these three colors, since the rose-purple group has the highest C\* value, the white group the lowest, and the pink group an intermediate value (Table 2).

**Figure 1.** Principal component analysis of petal color of *P. limprichtii*. Distribution based on bivariate values of a\* (redness and greenness) and b\* (yellowness and blueness). a\* means difference in red and green, b\* means difference in yellow and blue.


**Table 2.** Color parameters of three distinct colors of *P. limprichtii* petal.

RHS, Royal horticulture society color chart evaluation index; L\*, lightness; a\*, b\*, chromatic components; C\*, chroma (brightness).
