03003nas a2200229   4500008004100000245011300041210006900154260001200223300001600235490000700251520223800258653000902496653002802505653002202533653002102555653002502576653001702601100001302618700001102631700001402642856011702656       2005                        eng d00aGenetic consequence of restricted habitat and population decline in endangered Isoetes sinensis (Isoetaceae)0 aGenetic consequence of restricted habitat and population decline  c2005///  a1265 - 12740 v963 a• Background and Aims: Isoetes sinensis (Isoeteaceae) is a critically endangered aquatic quillwort in eastern China. Rapid decline of extant population size and local population extinction have occurred in recent years and have raised great concerns among conservationists. • Methods: Amplified fragment length polymorphisms (AFLPs) were used to investigate the genetic variation and population structure of seven extant populations of the species. • Key Results: Eight primer combinations produced a total of 343 unambiguous bands of which 210 (61·2 %) were polymorphic. Isoetes sinensis exhibited a high level of intra-population genetic diversity (H E) = 0·118; hs = 0·147; I = 0·192; P = 35·2 %). The genetic variation within each of the populations was not positively correlated with their size, suggesting recent population decline, which is well in accordance with field data of demographic surveys. Moreover, a high degree of genetic differentiation (FST = 0·535; G ST = 0·608; θB = 0·607) was detected among populations and no correlation was found between geographical and genetic distance, suggesting that populations were in disequilibrium of migration-drift. Genetic drift played a more important role than gene flow in the current population genetic structure of I. sinensis because migration of I. sinensis is predominantly water-mediated and habitat range was highly influenced by environment changes. • Conclusions: Genetic information obtained in the present study provides useful baseline data for formulating conservation strategies. Conservation management, including both reinforcement for in situ populations and ex situ conservation programmes should be carefully designed to avoid the potential risk of outbreeding depression by admixture of individuals from different regions. However, translocation within the same regional population should be considered as a measure of genetic enhancement to rehabilitate local populations. An ex situ conservation strategy for conserving all extant populations to maximize genomic representation of the species is also recommended. © The Author 2005. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved.10aAFLP10aGenetic differentiation10aGenetic diversity10aIsoetes sinensis10aPopulation structure10aPteridophyte1 aKang, M.1 aYe, Q.1 aHuang, H.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-27944462292&partnerID=40&md5=26404edf2320e666820f93f6dd369ebf02543nas a2200229   4500008004100000245016000041210006900201260001200270300001400282490000800296520175700304653000902061653001202070653002202082653001202104653001402116653002502130100001202155700001302167700001602180856011702196       2009                        eng d00aGenetic diversity and population structure of diploid and polyploid species of isoetes in east asia based on amplified fragment length polymorphism markers0 aGenetic diversity and population structure of diploid and polypl  c2009///  a496 - 5040 v1703 aIsoetes L. is critically endangered in areas of East Asia, including Taiwan, Japan, and South Korea. The genetic diversity and the population structure of six Isoetes species from East Asia were evaluated by using amplified fragment length polymorphism (AFLP). Three AFLP-selective primer combinations generated a total 923 amplification products, of which 919 (99.6%) were polymorphic. The levels of genetic diversity of two diploid species (I. taiwanensis [percentage of polymorphic loci (PPL) = 33.1%-38.3%] and I. asiatica [PPL = 49.0%]) are higher than those of polyploid species (tetraploid: I. jejuensis [PPL = 9.3%-29.3%] and I. hallasanensis [PPL = 22.3%]; hexaploid: I. coreana [PPL = 1.6%-20.6%] and I. japonica [PPL = 5.6%-20.5%]). Higher genetic differentiation was detected for populations of I. coreana (0B = 0.730) than for the diploid species I. taiwanensis (0B = 0.074). In addition, analysis of molecular variance showed that a large proportion (79.8%) of genetic differentiation existed among population of I. coreana. However, 93.2% of the total genetic variation was attributed to differentiation within populations of I. taiwanensis. A neighbor-joining dendrogram resulted in three clusters, one for I. asiatica, one for I. japonica, and one for the rest of the species, subdivided into two: (1) I. taiwanensis/I. jejuensis and (2) I. coreana/I. hallasanensis. Furthermore, individuals from each population of I. coreana and I. jejuensis were clustered into population-specific subclusters. The probable causes of the current pattern of genetic variation and population structure are discussed, and suggestions on the future protection of Isoetes species are also given. © 2009 by The University of Chicago. All rights reserved.10aAFLP10aDiploid10aGenetic diversity10aIsoetes10aPolyploid10aPopulation structure1 aKim, C.1 aShin, H.1 aChoi, H.-K.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-67649230633&partnerID=40&md5=794650fbe3653559e7cb90004dfa45c6