Optimal sampling strategies for core collections of plant genetic resources

  • A. H. D. Brown
  • D. J. Schoen
Part of the EXS book series (EXS, volume 68)


A core collection of crop germplasm aims to represent the genetic diversity in a single collection or in a crop species with minimum similarity between its entries. Core collections have a major role to play in conserving genetic resources and using them in plant improvement. Core selection can be based on stratified sampling from groups of related accessions. Elementary neutral theory indicates that the relative number from each group should be proportional to its level of polymorphism. This procedure has some biases when alleles are finite in number, or heterotic, or deleterious. However, in general, the weighting strategy is in practice robust to these departures from the assumptions underlying theory. Variation in divergence among populations is a factor that merits attention. In general, weighting in conservation should include both elements of richness and degree of divergence.


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Copyright information

© Springer Basel AG 1994

Authors and Affiliations

  • A. H. D. Brown
    • 1
  • D. J. Schoen
    • 2
  1. 1.Division of Plant IndustryCSIROCanberraAustralia
  2. 2.Department of BiologyMcGill UniversityMontrealCanada

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