Genetic variation at marker loci and in quantitative traits in natural populations of Arabidopsis thaliana.

Genetic variation was studied in quantitative traits and molecular markers in six natural Scandinavian populations of Arabidopsis thaliana. Only two of the populations had several molecular marker haplotypes and significant between-family variance components in quantitative traits. There was no genetic variation in the other four populations. The differentiation between the populations was high in both molecular markers and quantitative traits, with FST estimates of above 0.60 in almost all traits. The patterns of variation of the neutral markers and morphological and phenological traits were consistent in all the analyses, as opposed to what has been found in predominantly outcrossing species. The general picture of the level and distribution of genetic variance agrees with the information from other predominantly inbreeding species.