Abstract:

Rhododendron huadingense is a rare and endangered wild plant species endemic to Zhejiang Province, China, with narrow distribution and very few individuals, thus this species needs to be protected. In this study, leaves of R. huadingense from different populations were collected, and SRAP (sequence related amplified polymorphism) molecular marker technology was applied to study its genetic diversity. Fifty genomic DNA samples were used for PCR amplification. The results indicated 8 pairs of primers with high levels of polymorphism, clear bands, and high reliability were screened from 140 primer pairs. Totally, 263 bands were detected, including 261 polymorphic sites, and the percentage of the polymorphic band reached 99.24%. On species level, the number of observed alleles (N_a), number of effective alleles (N_e), Nei’s gene diversity (H), and Shannon’s information index (I) were 1.992 4, 1.340 1, 0.221 5, and 0.357 9, respectively, revealing its high genetic diversity on species level. On population level, the coefficient of genetic differentiation (G_st) and gene flow (N_m) were 0.459 6 and 0.587 8, respectively, indicating genetic differentiation and gene flow have occurred among populations, and most of the variation existed within populations. UPGMA results showed samples from 5 populations could be divided into 5 groups, which were consistent with principal component analysis results. Studies on genetic diversity of R. huadingense provided insights on protection and utilization of this rare plant species.

Key words: Rhododendron huadingense, genetic diversity, relationship