ASSESSMENT OF GENETIC DIVERSITY AND POPULATION STRUCTURE OF ENDANGERED CAMELLIA CHEKIANGOLEOSA HU USING ISSR MARKERS

The genetic diversity of 210 individuals from seven Camellia chekiangoleosa Hu populations was analyzed using ISSR markers. Results revealed an extraordinarily high level of genetic diversity at the species level. The total percentage of polymorphic loci (P) was 96.88%. Shannon's information index (I) and Nei's gene diversity (h) were 0.4966 and 0.3331 in the species, respectively. At the population level, the genetic diversity of C. chekiangoleosa Hu was relatively low. The mean values of P, I, and h were 59.79%, 0.3106, and 0.2077, respectively. The level of genetic differentiation among populations was lower than that within populations, and a certain level of genetic differentiation (G(sT) = 0.3758) was observed among the populations. Analysis of molecular variance revealed that among-population, among-region, and within-population components accounted for 28.0%, 12.0%, and 60.0% of the total variations, respectively. Genetic differentiation was high (0.6242), and the gene flow was low (0.8304). These results suggested that population isolation and inbreeding regression played major roles in genetic differentiation among the C.chekiangoleosa Hu populations. The pair wise mean genetic distance among the populations was 0.1696.