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Gene flow in an endangered willow Salix hukaoana (Salicaceae) in natural and fragmented riparian landscapes

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Abstract

Salix hukaoana is an endangered riparian pioneer tree that is distributed within a restricted area of Japan. Microsatellite genetic variations and genetic structures were investigated in 80 subpopulations patchily distributed within five river basins with varying degrees of habitat fragmentation. The correlation between geographic distance and genetic distance based on the Bayesian assignment test was significant across relatively intact riparian habitats, with steeper slopes of regression for more densely grouped subpopulations, suggesting restricted gene flow. However, the correlation became less apparent with increasing spacing of the habitat patches. These contradictory results are attributed to the increased chance of long-distance dispersal of sexual propagules among more isolated habitat patches. The observed accumulation of genetic diversity with increasing distance downstream along a few, but not all, of the rivers and the results of assignment tests suggested a downstream directionality of gene flow. The results of this study illustrate the patterns of genetic diversity and contemporary dispersal of S. hukaoana, and provide important insights into understanding the gene dispersal of riparian trees and into the conservation of genetic resources for this species.

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References

  • Andersson E, Nolsson C, Johansson ME (2000) Plant dispersal in boreal rivers and its relation to the diversity of riparian flora. J Biogeogr 27:1095–1106

    Article  Google Scholar 

  • Bacles CFE, Burczyk J, Lowe AJ, Ennos RA (2005) Historical and contemporary mating patterns in remnant populations of the forest tree Fraxinus excelsior L. Evolution 59:979–990

    PubMed  Google Scholar 

  • Ban N, Ide Y (2004) Life historical traits of Salix hukaoana along the Yubiso River. Bull Tokyo Univ For (in Japanese) 112:35–43

    Google Scholar 

  • Bohonak AJ (2002) IBD (isolation by distance): a program for analyses of isolation by distance. J Hered 93:153–154

    Article  CAS  PubMed  Google Scholar 

  • Castric V, Bernatchez L (2003) Individual assignment test reveals differential restriction to dispersal between two salmonids despite no increase of genetic differences with distance. Mol Ecol 13:1299–1312

    Article  Google Scholar 

  • Cornuet JM, Luikart J (1996) Description and power analysis of the two for detecting recent population bottlenecks from allele frequency data. Genetics 144:2001–2014

    CAS  PubMed  Google Scholar 

  • Drezner TD, Fall PL, Stromberg JC (2001) Plant distribution and dispersal mechanism at the Hassayampa River Preserve, Arizona, USA. Glob Ecol Biogeogr 10:205–217

    Article  Google Scholar 

  • Environment Agency of Japan (2000) Threatened wildlife of Japan: red data book, 2nd edn, vol 8, vascular plants. Japan Wildlife Research Center, Tokyo

    Google Scholar 

  • Fisher MJ (1928) The morphology and anatomy of the flowers of the Salicaceae I. Am J Bot 15:307–326

    Article  Google Scholar 

  • Gage EA, Cooper DJ (2005) Patterns of willow seed dispersal, seed entrapment, and seedling establishment in a heavily browsed montane riparian ecosystem. Can J Bot 83:678–687

    Article  Google Scholar 

  • Gornall RJ, Hollingsworth PM, Preston CD (1998) Evidence for spatial structure and directional gene flow in a population of an aquatic plant, Potamogeton coloratus. Heredity 80:414–421

    Article  Google Scholar 

  • Goudet J (1995) Fstat version 1.2: a computer program to calculate Fstatistics. J Hered 86(6):485–486

    Google Scholar 

  • Hurlbert SH (1971) The nonconcept of species diversity: a critique and alternative parameters. Ecology 52:577–586

    Article  Google Scholar 

  • Imbert E, Lefèvre F (2003) Dispersal and gene flow of Populus nigra (Salicaceae) along a dynamic river system. J Ecol 91:447–456

    Article  Google Scholar 

  • Jacquemyn H, Honnay O, Van Looy K, Breyne P (2006) Spatiotemporal structure of genetic variation of a spreading plant metapopulation on dynamic riverbanks along the Meuse River. Heredity 96:471–478

    Article  CAS  PubMed  Google Scholar 

  • Jansson R, Zinko U, Merritt DM, Nilsson C (2005) Hydrochory increases riparian plant species richness: a comparison between a free-flowing and a regulated river. J Ecol 93:1094–1103

    Article  Google Scholar 

  • Kalinowski ST (2005) HP-RARE 1.0: a computer program for performing rarefaction on measures of allelic richness. Mol Ecol Notes 5:187–189

    Article  CAS  Google Scholar 

  • Kikuchi S, Suzuki W, Ban N, Kanazashi A, Yoshimaru H (2005) Characterization of eight polymorphic microsatellites in endangered willow Salix hukaoana. Mol Ecol Notes 5:869–870

    Article  CAS  Google Scholar 

  • Kimura A (1973) Salicis nova species ex regione Okutonensi in Japonia. J Jpn Bot 48:321–326 (in Japanese with Latin description)

    Google Scholar 

  • Klein EK, Lavigne C, Gouyon P-H (2006) Mixing of propagules from discrete sources at long distance: comparing a dispersal tail to an exponential. BMC Ecol 6:3

    Article  PubMed  Google Scholar 

  • Kudoh H, Whigham DF (1997) Microgeographic genetic structure and gene flow in Hibiscus moscheutos (Malvaceae) populations. Am J Bot 84:1285–1293

    Article  Google Scholar 

  • Liu Y, Wang Y, Huang H (2006) High interpopulation genetic differentiation and unidirectional linear migration patterns in Myricaria laxiflora (Tamaricaceae), an endemic riparian plant in the Three Gorges Valley of the Yangtze River. Am J Bot 93:206–215

    Article  Google Scholar 

  • Lundqvist E, Andersson E (2001) Genetic diversity in populations of plants with different breeding and dispersal strategies in a free-flowing boreal river system. Hereditas 135:75–83

    Article  CAS  PubMed  Google Scholar 

  • Naiman RJ, Décamps H (1997) The ecology of interfaces: riparian zones. Annu Rev Ecol Syst 28:621–658

    Article  Google Scholar 

  • Nilsson C, Andersson E, Merritt DM, Johansson ME (2002) Differences in riparian flora between riverbanks and river lakeshores explained by dispersal traits. Ecology 83:2878–2887

    Article  Google Scholar 

  • Ohashi H, Kikuchi S, Sashimura N, Fujiwara R (2007) Distribution of Salix hukaoana Kimura (Salicaceae). J Jpn Bot 82:242–244

    Google Scholar 

  • Paetkau D, Waits IP, Clarkson PL, Craighead I, Strobeck C (1997) An empirical evaluation of genetic distance statistics using microsatellite data from bear (Ursidae) populations. Genetics 147:1943–1957

    CAS  PubMed  Google Scholar 

  • Pálsson S (2004) Isolation by distance, based on microsatellite data, tested with spatial autocorrelation (SPAIDA) and assignment test (SPASSIGN). Mol Ecol Notes 4:143–145

    Article  Google Scholar 

  • Peakall R, Smouse PE (2006) GenAlEx 6: genetic analysis in Excel. Population genetic software for teaching and research. Mol Ecol Notes 6:288–295

    Article  Google Scholar 

  • Piry S, Luikart G, Cornuet JM (1999) BOTTLENECK: a computer program for detecting recent reductions in effective population size from allele frequency data. J Hered 90:502–503

    Article  Google Scholar 

  • Piry S, Alapetite A, Cornuet J-M, Paetkau D, Baudouin L, Estoup A (2004) GeneClass2: a software for genetic assignment and first-generation migrant detection. J Hered 95:536–539

    Article  CAS  PubMed  Google Scholar 

  • Rannala B, Mountain JL (1997) Detecting immigration by using multilocus genotypes. Proc Natl Acad Sci USA 94:9197–9201

    Article  CAS  PubMed  Google Scholar 

  • Ritland K (1988) Genetic differentiation, diversity, and inbreeding in the mountain monkeyflower (Mimulus caespitosus) of the Washington Cascades. Can J Bot 67:2017–2024

    Article  Google Scholar 

  • Rood SR, Kalischuk AR, Polzin ML, Braatne JH (2003) Branch propagation, not cladoptosis, permits dispersive, clonal reproduction of riparian cottonwoods. For Ecol Manag 186:227–242

    Article  Google Scholar 

  • Seiwa K, Tozawa M, Ueno N, Kimura M, Yamasaki M, Maruyama K (2008) Roles of cottony hairs in directed seed dispersal in riparian willows. Plant Ecol 198:27–35

    Article  Google Scholar 

  • Suzuki W, Kikuchi S (2006) Floristic composition and stand structure of riparian forests in the Tadami River basin, and the ecological distribution of an endangered tree, Salix hukaoana. Jpn J Conserv Ecol 11:85–93 (in Japanese with English abstracts)

    Google Scholar 

  • Tamura S, Kudo G (2000) Wind pollination and insect pollination of two temperate willow species, Salix miyabeana and Salix sachalinensis. Plant Ecol 147:185–192

    Article  Google Scholar 

  • Tero N, Aspi J, Siikanäki P, Jäkäläniemi A, Tuomi J (2003) Genetic structure and gene flow in a metapopulation of an endangered plant species, Silene tatarica. Mol Ecol 12:2073–2085

    Article  CAS  PubMed  Google Scholar 

  • White GM, Boshier DH, Powell W (2002) Increased pollen flow counteracts fragmentation in a tropical dry forest: an example from Swietenia humilis Zuccarini. Proc Natl Acad Sci USA 99:2038–2042

    Article  CAS  PubMed  Google Scholar 

  • Yeh FC, Yang RC, Boyle TJB (1999) POPGENE, version 1.31. Molecular Biology and Biotechnology Centre, University of Alberta, Edmonton. Available from http://www.ualberta.ca/~fyeh/

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Acknowledgments

We thank A. Kanazashi and H. Yoshimaru for their valuable comments and advice, and Dr. Barney Davies and anonymous reviewers for their comments on an early version of the manuscript. We are grateful to I. Nikkuni and T. Abe for providing information helpful for our fieldwork in the Tadami River basin and in the Tone River basin, respectively, and to E. Ihara for assistance in the laboratory experiments. This study was supported by a grant from the Ministry of the Environment of Japan for the research project “Fundamental Research on In Situ Conservation of Endangered Tree Species”.

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Authors and Affiliations

  1. Forestry and Forest Products Research Institute, 1 Matsunosato, Tsukuba, Ibaraki, 305-8687, Japan

    Satoshi Kikuchi & Wajiro Suzuki

  2. Department of Ecosystem Studies, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo, Tokyo, 113-8657, Japan

    Naoko Sashimura

Authors
  1. Satoshi Kikuchi
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  2. Wajiro Suzuki
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  3. Naoko Sashimura
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Correspondence to Satoshi Kikuchi.

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Kikuchi, S., Suzuki, W. & Sashimura, N. Gene flow in an endangered willow Salix hukaoana (Salicaceae) in natural and fragmented riparian landscapes. Conserv Genet 12, 79–89 (2011). https://doi.org/10.1007/s10592-009-9992-z

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  • DOI: https://doi.org/10.1007/s10592-009-9992-z

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