Study on Genetic Diversity of Orchidantha chinensis (Lowiaceae)

Inter-simple sequence repeats (ISSR) marker was used to analyze the genetic diversity and differentiation of 137 individuals within and among 7 populations of Orchidantha chinensis, an endangered species, in Guangdong Province. Ten ISSR primers generated 101 bands, of which 58 (57.43%) were polymorphic. ISSR diversity within the population was lower than that among the populations (at species level: P=57.43%, H=0.1254, I=0.2000; at population level: P=18.24%, H=0.057, I=0.0876). Based on Nei's GST value calculated by POPGENE1.31, gene diversity within populations was 0.1254±0.1686, Shannon information index was 0.2000±0.2429. Variation coefficient among populations was 0.5481, and that within population was 0.4519. The ranger of gentic identity among populations was from 0.8855 to 0.9511. Based on the gene diversity information available for Orchidantha, two management strategies are proposed. A conservation area is suggested to be established in Honghuatan (HHT) where is considered to be an optimal habitat for O. chinensis growth. And because of the differentiation among the populations, cross transplantation is suggested in order to enhance the gene flow among the populations. By this means, the genetic diversity resources of the species could be preserved to the greatest extent.