Comparative study of genetic variation and differentiation of two pedunculate oak (Quercus robur) stands using microsatellite and allozyme loci

In a comparative study four codominant microsatellite loci and seven allozy me gene loci have been used to investigate the genetic variation and differ entiation of two pedunculate oak stands in North Germany. Both number and e ffective number of alleles were five to six times higher and the observed h eterozygosity was three times higher for the microsatellite than for the al lozyme loci. One stand showed an overall excess of homozygotes. In general the microsatellites were closer to Hardy-Weinberg expectation. The genetic distances between the two stands were distinctly higher for microsatellites . For most parameters microsatellites exhibited smaller interlocus variatio n than the allozymes. The different impact of population genetic processes on the genetic structure as assessed by microsatellites or allozymes is dis cussed.