02540nas a2200253   4500008004100000245016000041210006900201260001200270300001200282490000700294520168100301653001901982653002202001653001502023653001202038653001902050653002902069100001602098700001302114700001102127700001402138700001702152856011702169       2009                        eng d00aHigh allozyme diversity and unidirectional linear migration patterns within a population of tetraploid Isoetes sinensis, a rare and endangered pteridophyte0 aHigh allozyme diversity and unidirectional linear migration patt  c2009///  a52 - 580 v903 aIsoetes sinensis (Isoetaceae), an aquatic quillwort which occurs only in two fragmented sites of China as an allotetraploid, is critically endangered. Genetic variation among eight subpopulations of I. sinensis was examined in the Xin'an River (119°14′-15′E, 29°28′N) by using allozyme polymorphism. Eighteen loci of 10 enzyme systems were examined and used for the analysis of population genetic parameters. As expected for allotetraploids, fixed heterozygosity was found at four loci. A high level of genetic diversity was observed in the population, with mean number of alleles per loci of 1.8, and mean percentage of polymorphic loci of 55.6%, which were much higher than the average values in fern species. The genetic variation within each subpopulation was not positively correlated with its size, which may be explained by high gene flow (Nm = 2.57), clonal reproduction and fixed heterozygosity of allopolyploid. The I. sinensis population contained high clonal diversity (PD = 0.39, D = 0.95), indicating the successful seedling recruitment of the population. Significant positive relationship was detected between clonal diversity and the size of subpopulation. Partitioning the genetic diversity indicated that 91.1% of the genetic variation was within subpopulations and only 8.9% existed among subpopulations. The migration pattern of I. sinensis along the Xin'an River is best explained by a source-sink model, but with unidirectional gene flow among subpopulations underlined by hydrochoric force. The results were then discussed in relation to both in situ and ex situ conservation efforts of the population. © 2008 Elsevier B.V. All rights reserved.10aAllotetraploid10aGenetic diversity10aHydrochory10aIsoetes10aRiparian plant10aUnidirectional migration1 aChen, Y.-Y.1 aYang, W.1 aLi, W.1 aLi, Z.-Z.1 aHuang, H.-W.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-54249105798&partnerID=40&md5=962f14606c468408a8b8d98333cd329202091nas a2200229   4500008004100000245013800041210006900179260001200248300001400260490000800274520130400282653000901586653002201595653002201617653002301639653002801662100001601690700001301706700001101719700001401730856011701744       2010                        eng d00aGenetic diversity and population structure of the endangered alpine quillwort Isoetes hypsophila Hand.-Mazz. revealed by AFLP markers0 aGenetic diversity and population structure of the endangered alp  c2010///  a127 - 1390 v2903 aIsoetes hypsophila Hand.-Mazz. (Isoetaceae) is an endangered quillwort endemic to the Qinghai-Tibetan Plateau. Genetic variation and population structure of 12 I. hypsophila populations were examined by using amplified fragment length polymorphism (AFLP) markers. Eight primer pairs produced a total of 472 unambiguous bands, of which 229 (48.5%) were polymorphic. Intra-population genetic variation of Isoetes hypsophila was low (PP = 14.9%, HE = 0.039, hs = 0.084 and I = 0.061). The F statistics calculated by different approaches consistently revealed high genetic differentiation among populations, contributing approximately 50% of total gene diversity. Four genetic groups corresponding to four geographic regions were detected, indicating significant geographic structure. Our results suggest that both ongoing evolutionary forces (e.g., inbreeding system, bottlenecks resulting from fluctuation of water level) and historical events (e.g., orogenic movements which reduce gene flow among populations, repeated population retreat, and recolonization during ice ages) may have contributed to the genetic structure of I. hypsophila. In conservation, attention should be paid to preserving every population, and intra-region translocations can currently be recommended. © 2010 Springer-Verlag.10aAFLP10aAquatic quillwort10aGenetic structure10aIsoetes hypsophila10aQinghai-Tibetan Plateau1 aChen, Y.-Y.1 aLiao, L.1 aLi, W.1 aLi, Z.-Z.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-78149498133&partnerID=40&md5=4c18cfb671d1d50e919e742e3bf8659301725nas a2200241   4500008004100000245012600041210006900167260001200236300001600248490000700264520092400271653002401195653002201219653001501241653002301256653002101279653001901300100001101319700001201330700001301342700001101355856011701366       2012                        eng d00aMicrosatellite primers in the endangered quillwort Isoetes hypsophila (Isoetaceae) and cross-amplification in I. sinensis0 aMicrosatellite primers in the endangered quillwort Isoetes hypso  c2012///  ae184 - e1860 v993 aPremise of the study: The first microsatellite primers were developed for Isoetes hypsophila, an endangered quillwort species endemic to the Qinghai-Tibetan Plateau in China, to further describe its genetic variability and population structure. We also examined their cross-amplification in a congeneric species, I. sinensis. Methods and Results: Using the Fast Isolation by AFLP of Sequences COntaining Repeats (FIASCO) protocol, nine microsatellite loci were isolated and characterized in 32 samples from four natural populations of I. hypsophila. The primers amplified di-and hexanucleotide repeats with three to 11 alleles per locus. Seven of nine primers were cross-amplified in I. sinensis with two to seven alleles per locus. Conclusion: The microsatellite loci primers will be useful for studies of genetic diversity and gene flow in natural populations of Isoetes species. © 2012 Botanical Society of America.10aCross-amplification10aGenetic diversity10aIsoetaceae10aIsoetes hypsophila10aIsoetes sinensis10aMicrosatellite1 aLi, Z.1 aHan, Q.1 aChen, Y.1 aLi, W.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-84860573611&partnerID=40&md5=4de1802063e8ced0a9e32ab46966d215