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Increased inbreeding and inter-species gene flow in remnant populations of the rare Eucalyptus benthamii

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Abstract

Eucalyptus benthamii Maiden & Cambage is a forest tree of interest for conservation and plantation forestry. It is vulnerable to extinction, occurring on the alluvial floodplains of the Nepean River and its tributaries, south-west of Sydney, Australia. These floodplains were largely cleared of native vegetation for agriculture by the mid-1800s. Flooding of the Cox Valley for Sydney’s water supply further decreased the species distribution. The species is now confined to one population of approximately 6500 trees in the Kedumba valley and three remnant populations on the Nepean River at Bents Basin (about 300 trees), Wallacia (nine trees) and Camden (about 30 trees). Genetic analysis of the four populations using microsatellite markers revealed significant divergence among all populations, despite the Bents Basin, Wallacia and Camden remnants being separated by distances of only a few kilometres. Trees in these populations have been estimated to range from 35 to 200 years old, suggesting genetic divergence among populations occurred prior to land clearing. To investigate the impact of fragmentation on the next generation, outcrossing rates were estimated from 41 families. While no direct relationship was found between population size and outcrossing rates, fragmentation and the isolation of trees appears to have resulted in higher levels of selfing and biparental inbreeding in seed collected from the Camden and Wallacia remnants. There was also evidence from seedling morphology that inter-species gene flow increased with fragmentation since 20% of the progeny from Camden and 30% of the progeny from Wallacia were hybrids. Seed viability and germination rates were significantly lower in the remnant populations, reducing their value as seed sources for regeneration and plantation forestry. To maintain the genetic integrity of the remnant populations, germplasm should be sourced from the local area. Outcrossed, non-hybrid seed could be produced by controlled pollination in ex-situ conservation stands or by using seedling morphology and microsatellites to screen seedlings from the remnant populations.

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References

  • DH Benson (1985) ArticleTitleAspects of the ecology of a rare tree species, Eucalyptus benthamii, at Bents Basin, Wallacia Cunninghamia 1 371–383

    Google Scholar 

  • DH Benson J Howell L McDougall (1996) Mountain Devil to Mangrove Royal Botanic Gardens Sydney

    Google Scholar 

  • RPV Brondani C Brondani R Tarchini D Grattapaglia (1998) ArticleTitleDevelopment, characterization and mapping of microsatellite markers in Eucalyptus grandis and E. urophylla Theor. Appl. Genet 97 816–827 Occurrence Handle1:CAS:528:DyaK1cXotVaht7o%3D

    CAS  Google Scholar 

  • Brooker MIH, Kleinig DA (1999) Field Guide to Eucalypts Volume 1. South Eastern Australia (revised edn). Bloomings Books, Melbourne.

  • AHD Brown (1990) Genetic characterisation of plant mating systems. Ch. 9 AHD Brown MT Clegg AL Kahler BS Weir (Eds) Plant Population Genetics, Breeding and Genetic Resources Sinauer Associates. Inc Sunderland, MA 145–162

    Google Scholar 

  • GE Burrows (2000) ArticleTitleSeed production in woodland and isolated trees of Eucalyptus melliodora (yellow box, Myrtaceae) in the South Western Slopes of New South Wales Aust. J. Bot 48 681–685

    Google Scholar 

  • PA Butcher ER Williams (2001) ArticleTitleVariation in outcrossing rates and growth in Eucalyptus camaldulensis from the Petford Region Queensland; evidence of outbreeding depression Silv. Genet 51 6–12

    Google Scholar 

  • M Byrne MI Marquez-Garcia T Uren DS Smith GF Moran (1996) ArticleTitleConservation and genetic diversity of microsatellite loci in the genus Eucalyptus Aust. J. Bot 44 331–341 Occurrence Handle1:CAS:528:DyaK28Xltleku7c%3D

    CAS  Google Scholar 

  • JF Crow M Kimura (1970) An Introduction to Population Genetics Theory Harper and Row New York

    Google Scholar 

  • SA Cunningham (2000) ArticleTitleDepressed pollination in habitat fragments causes low fruit set Proc. R. Soc. Lond. B 267 1149–1152 Occurrence Handle1:STN:280:DC%2BD3M%2FhtFCksw%3D%3D

    CAS  Google Scholar 

  • MF Ellis M Sedgley (1992) ArticleTitleFloral morphology and breeding system of three species of Eucalyptus, section Bisectaria (Myrtaceae) Aust. J. Bot 40 249–262

    Google Scholar 

  • OH Frankel AHD Brown JJ Burdon (1995) The Conservation of Plant Biodiversity Cambridge University Press Cambridge

    Google Scholar 

  • JC Glaubitz LC Emebiri GF Moran (2001) ArticleTitleDinucleotide microsatellites from Eucalyptus sieberi: inheritance, diversity, and improved scoring of single-base differences Genome 44 1041–1045 Occurrence Handle1:CAS:528:DC%2BD38XjvVOgug%3D%3D Occurrence Handle11768207

    CAS  PubMed  Google Scholar 

  • Goudet J (2001) FSTAT, a program to estimate and test gene diversities and fixation indices (version 2.9.3). Available from http://www.unil.ch/izea/softwares/fstat.html.

  • AR Griffin PP Cotterill (1988) ArticleTitleGenetic variation in growth of outcrossed, selfed and open-pollinated progenies of Eucalyptus regnans and some implications for breeding strategy Silv. Genet 37 124–131

    Google Scholar 

  • AR Griffin IP Burgess L Wolf (1988) ArticleTitlePatterns of natural and manipulated hybridisation in the genus Eucalyptus L’Herit. – a review Aust. J. Bot 36 41–66

    Google Scholar 

  • CM Hardner BM Potts (1995) ArticleTitleInbreeding depression and changes in variation after selfing in Eucalyptus globulus ssp. globulus Silv. Genet 44 46–54

    Google Scholar 

  • LM Hodgson (1976) ArticleTitleSome aspects of flowering and reproductive behaviour of Eucalyptus grandis (Hill) Maiden at J.D.M. Keet Research Station 2 The fruit, seed, seedlings, self-fertility, selfing and inbreeding effects Sth Afr. For. J 98 32–43

    Google Scholar 

  • SH James WJ Kennington (1993) ArticleTitleSelection against homozygotes and resource allocation in the mating system of Eucalyptus camaldulensis Dehnh Aust. J. Bot 41 389–391

    Google Scholar 

  • WJ Kennington SH James (1997) ArticleTitleThe effect of small population size on the mating system of a rare clonal mallee, Eucalyptus argutifolia (Myrtaceae) Heredity 78 252–260

    Google Scholar 

  • Lewis PO, Zaykin D (2001) Genetic Data Analysis: Computer program for the analysis of allelic data. Version 1.0 (d16c). Free program distributed by the authors over the Internet from http://lewis.eeb.uconn.edu/lewishome/software.html.

  • TC Marshall J Slate LEB Kruuk JM Pemberton (1998) ArticleTitleStatistical confidence for likelihood-based paternity inference in natural populations Mol. Ecol 7 639–655 Occurrence Handle1:STN:280:DyaK1c3ps1Olsw%3D%3D Occurrence Handle9633105

    CAS  PubMed  Google Scholar 

  • MW McDonald M Rawlins PA Butcher JC Bell (2003) ArticleTitleRegional divergence and inbreeding in Eucalyptus cladocalyx (Myrtaceae) Aust. J. Bot 51 393–403

    Google Scholar 

  • GF Moran SD Hopper (1983) ArticleTitleGenetic diversity and insular population structure of the range granite rock species Eucalyptus caesia Benth Aust. J. Bot 31 161–172

    Google Scholar 

  • GF Moran SD Hopper (1987) Conservation of the genetic resources of rare and widespread eucalypts in remnant vegetation DA Saunders GW Arnold AA Burbidge AJM Hopkins (Eds) Nature Conservation: The Role of Remnants of Native Vegetation Surrey Beatty and Sons Sydney 151–162

    Google Scholar 

  • NSW National Parks and Wildlife Service (2003) Draft Eucalyptus benthamii, Eucalyptus copulans, Eucalyptus sp. Howes Swamp Creek Recovery Plan. NPWS, Sydney.

  • BM Potts JE Wiltshire (1997) Eucalypt genetics and genecology JE Williams JCZ Woinarski (Eds) Eucalypt Ecology Cambridge University Press Cambridge 56–91

    Google Scholar 

  • LM Pound MAB Wallwork BM Potts M Sedgley (2002) ArticleTitleSelf-incompatibility in Eucalyptus globulus ssp. globulus (Myrtaceae) Aust. J. Bot 50 365–372

    Google Scholar 

  • SM Prober AHD Brown (1994) ArticleTitleConservation of the grassy white box woodlands: population genetics and fragmentation of Eucalyptus albens Cons. Biol 8 1003–1013

    Google Scholar 

  • SM Prober C Tompkins GF Moran JC Bell (1990) ArticleTitleThe conservation genetics of Eucalyptus paliformis L Johnson et Blaxell and E. parvifolia Cambage, two rare species from south-eastern Australia Aust. J. Bot 38 79–95

    Google Scholar 

  • M Raymond F Rousset (1995) ArticleTitleGENEPOP (version 1.2): population genetics software for exact tests and ecumenicism J. Hered 86 248–249

    Google Scholar 

  • M Raymond F Rousset (1995) ArticleTitleAn exact test for population differentiation Evolution 49 1280–1283

    Google Scholar 

  • K Ritland (1989) ArticleTitleCorrelated matings in the partial selfer Mimulus guttatus Evolution 43 848–859

    Google Scholar 

  • K Ritland (2002) ArticleTitleExtensions of models for the estimation of mating systems using n independent loci Heredity 88 221–228 Occurrence Handle11920127

    PubMed  Google Scholar 

  • DL Robinson (1987) Program REML: Estimation of variance components in non-orthogonal data by residual maximum likelihood Scottish Agricultural Statistics Service Edinburgh

    Google Scholar 

  • JF Sampson SD Hopper SH James (1988) ArticleTitleGenetic diversity and the conservation of Eucalyptus crucis Maiden Aust. J. Bot 36 447–460

    Google Scholar 

  • Swain T-L (2001) Institute for Commercial Forestry Tree Improvement Project: Status Report Eucalyptus badjensis and Eucalyptus benthamii. ICFR Bulletin 09/2001, 1–19.

  • KA Thamarus K Groom J Murrell M Byrne GF Moran (2002) ArticleTitleA genetic linkage map for Eucalyptus globulus with candidate loci for wood, fibre, and floral traits Theor. Appl. Genet 104 379–387 Occurrence Handle1:CAS:528:DC%2BD38XislOgtrY%3D Occurrence Handle12582710

    CAS  PubMed  Google Scholar 

  • BS Weir (1996) Genetic Data Analysis II Methods for Discrete Population Genetic Data Sinauer Associates Inc Sunderland, MA

    Google Scholar 

  • BS Weir CC Cockerham (1984) ArticleTitleEstimating F-statistics for the analysis of population structure Evolution 38 1358–1370

    Google Scholar 

  • A Young T Boyle A Brown (1996) ArticleTitleThe population genetic consequences of habitat fragmentation for plants Trends Ecol. Evol 11 413–418

    Google Scholar 

Download references

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Author notes

  1. P. A. Butcher

    Present address: Kings Park and Botanic Garden, Fraser Avenue, West Perth, WA, 6005, Australia

Authors and Affiliations

  1. CSIRO Forestry and Forest Products, GPO Box E4008, Kingston, ACT, 2602, Australia

    A. K. Skinner & C. A. Gardiner

Authors
  1. P. A. Butcher
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  2. A. K. Skinner
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  3. C. A. Gardiner
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Correspondence to P. A. Butcher.

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Butcher, P.A., Skinner, A.K. & Gardiner, C.A. Increased inbreeding and inter-species gene flow in remnant populations of the rare Eucalyptus benthamii. Conserv Genet 6, 213–226 (2005). https://doi.org/10.1007/s10592-004-7830-x

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  • DOI: https://doi.org/10.1007/s10592-004-7830-x

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