title: Genetic diversity across natural populations of Dendrobium officinale, the endangered medicinal herb endemic to China, revealed by ISSR and RAPD markers.
abstract: Dendrobium officinale is a rare and endangered herb with special habitats and endemic to China. Genetic diversity was examined within and among nine natural populations using inter-simple sequence repeat (ISSR) and random amplified polymorphic (RAPD) for conservation. Both molecular markers revealed a high percentage (>89%) of polymorphic bands and ISSR markers detected more diversity than RAPD markers. Analysis of molecular variance (AMOVA) revealed that 78.84% (ISSR) and 78.88% (RAPD) of variability was partitioned among individuals within populations. This genetic structure was probably due to severe genetic drift resulting from habitat fragmentation and human overexploitation since 1950s. Moreover, there is a lack of significant association between genetic and geographic distances (r = 0.276; p > 0.05) in the populations of D. officinale. From the conservation point of view, populations GL, GS and GSD with higher genetic diversity should be protected firstly to maintain the species potential for evolutionary change and population YG with lower diversity but representing a novel evolutionary unit should also be paid more attention to during D. officinale conservation practice.
authors.affiliation: Jiailgsu Provicinal Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing 210046, China. dingge2001@yahoo.com.cn
authors.forename: Ge
authors.initials: G
authors.lastname: Ding
authors.forename: Xuexia
authors.initials: X
authors.lastname: Li
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Ding
authors.forename: Liang
authors.initials: L
authors.lastname: Qian
mesh_terms: D002681:China; D031667:Dendrobium / Q000235:genetics*; D019143:Evolution, Molecular; D005819:Genetic Markers / Q000235:genetics; D010946:Plants, Medicinal / Q000235:genetics*; D011110:Polymorphism, Genetic; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods
chemical_list: D005819:Genetic Markers