Genetic Erosion: Context Is Key

  • Deborah RogersEmail author
  • Patrick McGuire
Part of the Sustainable Development and Biodiversity book series (SDEB, volume 7)


Genetic erosion is a useful concept for conservationists, collection curators, natural lands managers, and practitioners of restoration and revegetation. However, there is variation in how the term has been used and how faithfully it follows from the genetic concepts upon which it was based. Genetic erosion is the loss of genetic diversity—often magnified or accelerated by human activities. It can result from habitat loss and fragmentation, but it also can result from a narrow genetic base in the original populations or collections or by practices that reduce genetic diversity. Just as loss of diversity is relative (to some baseline condition), so too is the biological significance of that loss, the management implications, and the human-applied value. Thus we emphasize the context in this chapter’s treatment of genetic erosion. Although few species-specific guidelines are available, practitioners can minimize the risk of genetic erosion by being familiar with the biology of the affected species (including breeding system, mode of reproduction, and pattern of genetic diversity). Narrowly based genetic collections should be avoided, providers of plant materials for revegetation projects should offer information on their collection methods, and nursery managers should endeavor to minimize diversity losses at all stages of nursery culture.


Genetic diversity Reforestation Restoration Revegetation Source materials Inbreeding Natural areas Conservation 



This chapter is based on a 2004 paper published in Native Plants Journal by DL Rogers (Genetic erosion: No longer just an agricultural issue, 5(2):112–122). The text has been revisited, updated, and enlarged.


  1. Bannister MH (1965) Sampling the pines of Guadalupe Island and Cedros Island. Internal Silviculture Report No. 49. Forest Research Institute, Rotorua, New ZealandGoogle Scholar
  2. Bartlett E, Novak SJ, Mack RN (2002) Genetic variation in Bromus tectorum (Poaceae): differentiation in the eastern United States. Am J Bot 89:602–612CrossRefPubMedGoogle Scholar
  3. Beatty GE, Reid N, Provan J (2014) Retrospective genetic monitoring of the threatened Yellow marsh saxifrage (Saxifraga hirculus) reveals genetic erosion but provides valuable insights for conservation strategies. Divers Distrib 20:529–537CrossRefGoogle Scholar
  4. Bever J, Felber F (1992) The theoretical population genetics of autopolyploidy. Oxford Sur Evol Biol 8:185–217Google Scholar
  5. Bijlsma R, Loeschcke V (2012) Genetic erosion impedes adaptive responses to stressful environments. Evol Appl 5:117–129CrossRefPubMedGoogle Scholar
  6. Brown AHD (2008) Indicators of genetic diversity, genetic erosion and genetic vulnerability for plant genetic resources for food and agriculture. Thematic Background Study for the Second Report on the State of the World’s Plant Genetic Resources for Food and Agriculture, 2010. Food and Agriculture Organization of the United Nations, Rome, Italy.
  7. Brown AHD, Briggs JD (1991) Sampling strategies for genetic variation in ex situ collections of endangered plant species 1. In: Falk DA, Holsinger KE (eds), Genetics and conservation of rare plants. Oxford University Press, New York, pp 99–119Google Scholar
  8. Brown AHD, Brubaker CL (2002) Indicators of sustainable management of plant genetic resources: how well are we doing? In: Engels JMM, Ramanatha Rao V, Brown AHD, Jackson MT (eds), Managing plant genetic diversity. CABI Publishing, Oxon, pp 249–262Google Scholar
  9. Buis S (2000) Writing woody plant specifications for restoration and mitigation practices. Native Plants J 1:116–119CrossRefGoogle Scholar
  10. Burton TL, Husband BC (2000) Fitness differences among diploids, tetraploids, and their triploid progeny in Chamerion angustifolium: mechanisms of inviability and implications for polyploid evolution. Evolution 54:1182–1191CrossRefPubMedGoogle Scholar
  11. Buza L, Young A, Thrall P (2000) Genetic erosion, inbreeding, and reduced fitness in fragmented populations of the endangered tetraploid pea Swainsona recta. Biol Conserv 93:177–186CrossRefGoogle Scholar
  12. Campbell RK, Sorensen FC (1984) Genetic implications of nursery practices. In: Duryea ML, Landis TD (eds) Forest nursery manual: production of bare root seedlings. Martinus Nijhoff, Dordrecht, pp 183–191CrossRefGoogle Scholar
  13. CBD (1992) Convention on biological diversity. Secretariat for the Convcention on Biological Diversity, Montreal, Quebec Canada.
  14. CBD (2001) Global Biodiversity Outlook 1. Secretariat of the Convention on Biological Diversity, Montreal, Quebec Canada.
  15. CBD (2010) Strategic plan for biodiversity 2011–2020. Secretariat of the Convention on Biological Diversity, Montreal, Quebec Canada.
  16. Charlesworth D, Charlesworth B (1987) Inbreeding depression and its evolutionary consequences. Annu Rev Ecol Syst 18:237–268CrossRefGoogle Scholar
  17. Charlesworth D, Willis JH (2009) The genetics of inbreeding depression. Nat Rev Genet 10:783–796CrossRefPubMedGoogle Scholar
  18. CNPS (2001) Guidelines for landscaping to protect native vegetation from genetic degradation. California Native Plant Society, Sacramento CA.
  19. Cole CT (2003) Genetic variation in rare and common plants. Annu Rev Ecol Evol Syst 34:213–237CrossRefGoogle Scholar
  20. CPC (Center for Plant Conservation) (1991) Genetic sampling guidelines for conservation collections of endangered plants. In: Falk DA, Holsinger KE (eds), Genetics and conservation of rare plants. Oxford University Press, New York, pp 225–238Google Scholar
  21. Crow JF (1993) Mutation, mean fitness, and genetic load. Oxford Sur Evol Biol 9:3–42Google Scholar
  22. Demauro MM (1993) Relationship of breeding system to rarity in the lakeside daisy (Hymenoxys acaulis var. glabra). Conserv Biol 7:542–550CrossRefGoogle Scholar
  23. Edmands S, Timmerman CC (2003) Modeling factors affecting the severity of outbreeding depression. Conserv Biol 17:883–892CrossRefGoogle Scholar
  24. Ellstrand NC, Elam DR (1993) Population genetic consequences of small population size: implications for plant conservation. Annu Rev Ecol Syst 24:217–242CrossRefGoogle Scholar
  25. El-Kassaby YA, Thomson AJ (1996) Parental rank change associated with seed biology and nursery practices in Douglas-fir. For Sci 42:228–235Google Scholar
  26. Falconer DS (1981) Introduction to quantitative genetics (2nd edn). Longman, New YorkGoogle Scholar
  27. Falk DA (1987) Integrated conservation strategies for endangered plants. Nat Areas J 7:118–123Google Scholar
  28. Falk DA, Holsinger KE (eds) (1991) Genetics and conservation of rare plants. Oxford University Press, New YorkGoogle Scholar
  29. FAO (1999) Global strategy for the management of farm animal genetic resources: executive brief. Food and Agriculture Organization of the United Nations, Rome.
  30. FAO (2007a) Global plan of action for animal genetic resources and the interlaken declaration. In: International technical conference on animal genetic resources for food and agriculture, Interlaken, Switzerland, 3–7 Sept 2007. Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations, Rome.
  31. FAO (2007b) The state of the world’s animal genetic resources. Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations, Rome.
  32. FAO (2010) The second report on the state of the world’s plant genetic resources for food and agriculture. Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations, Rome.
  33. FAO (2011) The second global plan of action for plant genetic resources for food and agriculture. In: FAO Council, Rome, Italy, 29 Nov 2011. Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations, Rome.
  34. FAO (2014) The state of the world’s forest genetic resources. Commission on Genetic Resources for Food and Agriculture, Food and Agriculture Organization of the United Nations, Rome.
  35. Frankham R, Ballou JD, Briscoe DA (2004) A primer of conservation genetics. Cambridge University Press, CambridgeCrossRefGoogle Scholar
  36. Futuyma DJ (1979) Evolutionary Biology. Sinauer, SunderlandGoogle Scholar
  37. Gitzendanner MA, Soltis PS (2000) Patterns of variation in rare and widespread plant congeners. Am J Bot 87:783–792CrossRefPubMedGoogle Scholar
  38. Given DR (1987) What the conservationist requires of ex situ collections. In: Branwell D, Hamann O, Heywood V, Synge H (eds) Botanic gardens and the world conservation strategy. Academic Press, London, pp 103–116Google Scholar
  39. Glémin S (2003) How are deleterious mutations purged? Drift versus nonrandom mating. Evolution 57:2678–2687CrossRefPubMedGoogle Scholar
  40. Glendinning D (1989) Some aspects of autotetraploid population dynamics. Theor Appl Genet 78:233–242CrossRefPubMedGoogle Scholar
  41. Guarino L, Ramanatha Rao V, Reid R (eds) (1995) Collecting Plant Genetic Diversity: Technical Guidelines. CAB International, WallingfordGoogle Scholar
  42. Guerrant EO (1992) Genetic and demographic considerations in the sampling and reintroduction of rare plants. In: Fiedler PL, Jain SK (eds), Conservation biology: the theory and practice of nature conservation, preservation, and management. Routledge, Chapman and Hall, Inc., New York, pp 321–344Google Scholar
  43. Guerrant EO (1996) Designing populations: demographic, genetic, and horticultural dimensions. In: Falk DA, Millar CI and Olwell M (eds), Restoring diversity: strategies for reintroduction of endangered plants. Island Press, Washington, pp 171–207Google Scholar
  44. Guerrant EO, Havens K, Maunder M (eds) (2004) Ex situ plant conservation: supporting species survival in the wild. Island Press, WashingtonGoogle Scholar
  45. Hamrick JL, Godt MJW (1990) Allozyme diversity in plant species. In: Brown AHD, Clegg MT, Kahler AL, Weir BS (eds) Plant population genetics, breeding, and genetic resources. Sinauer, Sunderland, pp 43–63Google Scholar
  46. Hufford KM, Mazer SJ (2003) Plant ecotypes: genetic differentiation in the age of ecological restoration. Trends Ecol Evol 18:147–155CrossRefGoogle Scholar
  47. Hipkins VD, DeWoody J (2014) Isozyme data indicate variation in ploidy and significant genetic structure in Acanthomintha ilicifolia (gray) gray, San Diego thornmint. Revised report to the Center for Natural Lands Management, NFGEL Project #279Google Scholar
  48. ITPGRFA (2004) International treaty on plant genetic resources for food and agriculture. Food and Agriculture Organization of the United Nations, Rome.
  49. Jensen DB, Torn MS, Hart J (1993) In our own hands: a strategy for conserving California’s biological diversity. University of California Press, Berkeley and Los Angeles, CaliforniaGoogle Scholar
  50. Karron JD (1987) A comparison of levels of genetc polymorphism and self-compatibility in geographically restricted and widespread plant congeners. Evol Ecol 1:47–58CrossRefGoogle Scholar
  51. Karron JD (1991) Patterns of genetic variation and breeding systems in rare plant species. In: Falk DA, Holsinger KE (eds), Genetics and conservation of rare plants. Oxford University Press, New York, pp 87–98Google Scholar
  52. Keeler KH (2004) Impact of intraspecific polyploidy in Andropogon gerardii (Poaceae) populations American. Midl Nat 152:63–74CrossRefGoogle Scholar
  53. Kitchen SG, McArthur ED (2001) Native or not: subjective labels and their application in wildland plantings. Native Plants J 2:21–24CrossRefGoogle Scholar
  54. Kitzmiller JH (1990) Managing genetic diversity in a tree improvement program. For Ecol Manage 35:131–149CrossRefGoogle Scholar
  55. Lawrence MJ, Marshall DF, Davies P (1995) Genetics of genetic conservation, I, sample size when collecting germplasm. Euphytica 84:89–99CrossRefGoogle Scholar
  56. Lacy RC (1987) Loss of genetic diversity from managed populations: interacting effects of drift, mutation, immigration, selection, and population subdivision. Conserv Biol 1:143–158CrossRefGoogle Scholar
  57. Ledig FT (1987) Genetic structure and conservation of California’s endemic and near-endemic conifers. In: Elias TS (ed), Conservation and management of rare and endangered plants. California Native Plant Society, Sacramento, pp 587–594Google Scholar
  58. Ledig FT (1991) Secret extinctions: the loss of genetic diversity in forest ecosystems. In: Fenger MA, Miller EH, Johnson JA, Williams EJR (eds), Our living legacy: proceedings of a symposium on biological diversity. Victoria, pp. 127–140Google Scholar
  59. Ledig FT (1992) Human impacts on genetic diversity in forest ecosystems. Oikos 63:87–108CrossRefGoogle Scholar
  60. Linder HP, Barker NP (2014) Does polyploidy facilitate long-distance dispersal? Ann Bot 113:1175–1183CrossRefPubMedPubMedCentralGoogle Scholar
  61. Linhart YB (1995) Restoration, revegetation, and the importance of genetic and evolutionary perspectives. In: Roundy BA, McArthur ED, Haley JS, Mann DK (eds), Proceedings: wildland shrub and arid land restoration symposium. General Technical Report INT-GTR-315. US Department of Agriculture, Forest Service, Intermountain Research Station, Ogden, pp 271–287Google Scholar
  62. Lippitt L, Anderson S, Epperson B (2013) San Diego thornmint seed and common garden study. Final report to the Center for Natural Lands Management, TemeculaGoogle Scholar
  63. Lynch M, Gabriel W (1990) Genetic load and the survival of small populations. Evolution 44:1725–1737CrossRefGoogle Scholar
  64. McNeely JA, Miller KR, Reid WV, Mittermeier RA, and Werner TB (1990) Conserving the world’s biological diversity. World Conservation Union, World Resources Institute, Conservation International, World Wildlife Fund-US, and the World Bank, WashingtonGoogle Scholar
  65. Meyer SE, Kitchen SG (1994) Life history variation in blue flax (Linum perenne: Linaceae) seed germination phenology. Am J Bot 81:528–535CrossRefGoogle Scholar
  66. Meyer SE, Monsen SB (1993) Genetic considerations in propagating native shrubs, forbs, and grasses from seed. In: Proceedings, Western Forest Nursery Association Symposium, Sept 14–18, 1992, Fallen Leaf Lake, CA. General Technical Report RM-GTR-221. US Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station, Fort Collins, pp 47–54Google Scholar
  67. Millar CI, Libby WJ (1989) Disneyland or native ecosystem: genetics and the restorationist. Restor Manage Notes 7:18–24Google Scholar
  68. Pappert RA, Hamrick JL, Donovan LA (2000) Genetic variation in Pueraria lobata (Fabaceae), an introduced, clonal, invasive plant of the southeastern United States. Am J Bot 87:1240–1245CrossRefPubMedGoogle Scholar
  69. Pellegrin D, Hauber DP (1999) Isozyme variation among populations of the clonal species, Phragmites australis (Cav.) Trin. ex Steudel. Aquat Bot 63:241–259CrossRefGoogle Scholar
  70. Reinhartz JA (1995) Planting state-listed endangered and threatened plants. Conserv Biol 9:771–781CrossRefGoogle Scholar
  71. Rogers DL, Ledig FT (1996) The status of temperate North American forest genetic resources. Report No. 16. University of California Genetic Resources Conservation Program, Davis.
  72. Rogers DL, Matheson AC, Vargas Hernández JJ, Guerra Santos JJ (2006) Genetic conservation of insular populations of Monterey pine (Pinus radiata D. Don). Biodiver Conserv 15:779–798CrossRefGoogle Scholar
  73. Saltonstall K (2002) Cryptic invasion by a non-native genotype of the common reed, Phragmites australis, into North America. Proc Natl Acad Sci USA 99:2445–2449CrossRefPubMedPubMedCentralGoogle Scholar
  74. Scarascia-Mugnozza GT, Perrino P (2002) The history of ex situ conservation and use of plant genetic resources. In: Engels JMM, Ramanatha Rao V, Brown AHD, Jackson MT (eds), Managing plant genetic diversity. CABI Publishing, Oxon, pp 1–22Google Scholar
  75. Schmid B (1994) Effects of genetic diversity in experimental stands of Solidago altissima: evidence for the potential role of pathogens as selective agents in plant populations. J Ecol 82:165–175CrossRefGoogle Scholar
  76. Tecic DL, McBride JL, Bowles ML, Nickrent DL (1998) Genetic variability in the federal threatened Mead’s milkweed, Asclepias meadii Torrey (Asclepiadaceae), as determined by allozyme electrophoresis. Ann Mo Bot Gard 85:97–109CrossRefGoogle Scholar
  77. Templeton AR, Shaw K, Routman E, Davis SK (1990) The genetic consequences of habitat fragmentation. Ann Mo Bot Gard 77:13–27CrossRefGoogle Scholar
  78. Thompson JN, Nuismer SL, Merg K (2004) Plant polyploidy and the evolutionary ecology of plant/animal interactions. Biol J Linn Soc 82:511–519CrossRefGoogle Scholar
  79. Tsutsui ND, Suarez AV, Holway DA, Case TJ (2000) Reduced genetic variation and the success of an invasive species. Proc Natl Acad Sci USA 97:5948–5953CrossRefPubMedPubMedCentralGoogle Scholar
  80. UNEP (1972) Declaration of the United Nations conference on the human environment. United Nations Environment Programme, Nairobi.
  81. Wang RL, Wendel JF, Dekker JH (1995) Weedy adaptation in Setaria spp. I. Isozyme analysis of genetic diversity and population genetic structure in Setaria viridis. Am J Bot 82:308–317CrossRefGoogle Scholar
  82. Williams SL (2001) Reduced genetic diversity in eelgrass transplantations affects both population growth and individual fitness. Ecol Appl 11:1472–1488CrossRefGoogle Scholar
  83. Williams SL, Davis CA (1996) Population genetic analyses of transplanted eelgrass (Zostera marina) beds reveal reduced genetic diversity in southern California. Restor Ecol 4:163–180CrossRefGoogle Scholar
  84. Wright S (1931) Evolution in Mendelian populations. Genetics 16:97–159PubMedPubMedCentralGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2015

Authors and Affiliations

  1. 1.Department of Plant SciencesUniversity of CaliforniaDavisUSA
  2. 2.Center for Natural Lands ManagementTemeculaUSA

Personalised recommendations