Species Identification and Genetic Diversity Analysis of Medicinal Plants Busch and Hand.-Mazz.

The classification system for the genus is highly complex. It is also the subject of ongoing debate. Busch and Hand.-Mazz. are perennial herbs of the genus . Dried roots of these two plants are used in traditional Chinese medicine. In this study, morphological observations and ISSR molecular markers were employed to discriminate between and , with the objective of gaining insights into the interspecies classification of . The pubescence on the inflorescence of was found to be appressed, while that on the inflorescence of was spread. UPGMA (unweighted pair-group method with arithmetic average) cluster analysis, PCoA (principal coordinates analysis), and Bayesian structural analysis divided the 199 individuals (99 individuals from DWM population and 100 individuals from QHL population) into two main branches, which is consistent with the observations of the morphology of pubescence on the inflorescence. These analyses indicated that and are distinct species. No diagnostic bands were found between the two species. Two primer combinations (UBC808 and UBC853) were ultimately selected for species identification of and . This study revealed high levels of genetic diversity in both ( = 0.254, = 0.395, = 95.85%) and ( = 0.291, = 0.445, = 94.58%). We may say, therefore, that ISSR molecular markers are useful for distinguishing and , and they are also suitable for revealing genetic diversity and population structure.