spagedi: a versatile computer program to analyse spatial genetic structure at the individual or population levels

  title={spagedi: a versatile computer program to analyse spatial genetic structure at the individual or population levels},
  author={Olivier J. Hardy and Xavier Vekemans},
  journal={Molecular Ecology Notes},
spag e d i version 1.0 is a software primarily designed to characterize the spatial genetic structure of mapped individuals or populations using genotype data of codominant markers. It computes various statistics describing genetic relatedness or differentiation between individuals or populations by pairwise comparisons and tests their significance by appropriate numerical resampling. spag e d i is useful for: (i) detecting isolation by distance within or among populations and estimating gene… 

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  • O. HardyX. Vekemans
  • Biology, Medicine
    Evolution; international journal of organic evolution
  • 2001
Numerical simulations showed that the striking difference in patterns observed at small and large geographic scales could be accounted for by a combination of isolation by distance within cytotypes; and partial reproductive barriers between cytotypes and/or recurrent formation of tetraploids.

Spatial effects and rare outcrossing events in Medicago truncatula (Fabaceae)

Interestingly, fine‐scale spatial structure could be observed in only one subpopulation suggesting that other mechanisms are acting elsewhere, the first study of fine spatial genetic structure in a predominantly selfing species.