Phenotypic Diversity in Natural Populations of Chimonanthus praecox

According to the morphology of leaf, fruit and seed and other 5 phenotypic traits of Chimonanthus praecox plants, the phenotypic diversity of C. praecox was analyzed by randomly choosing 9 natural populations as study objects in its distribution areas. The results showed that there was a great variation in morphological characteristics among the populations, the F values of the 8 phenotipic traits ranged from 0.99 to 65.90. There were significant differences or extremely significant differences in 6 of the 8 traits among the populations, except for the fruit length and unit grain weight indices. While inside the populations, there was significant difference only in the fruit width trait, and there were no significnat differences in other 7 traits within the populations. The mean phenotypic differentiation coefficient (Vst) of the 8 traits was 63.16%. The percentage of variance portion among populations was 8.90%, but 3.04% within the populations, indicating that the variance among populations was the main source of the phenotypic variation. The correlation analyses of the phenotypic traits with the geographical factors showed that there was extremely significant negative correlation between the width of fruit and latitude, and there was significant negative correlation between seed quantity, the unit grain weight and the latitude respectively. There was no significant correlation between 6 other phenotypic traits and the geographical factors. The UPGMA cluster analysis showed that the phenotypic traits of the 9 natural populations of C. praecox were not fully clustered in accordance with the geographical distance, and this conclusion was reflected by the interrupted island distribution pattern of C. praecox populations.