ALLOPOLYPLOID ORIGIN OF ARABIDOPSIS-SUECICA (FRIES) NORRLIN - EVIDENCE FROM CHLOROPLAST AND NUCLEAR GENOME MARKERS

The origin of the presumed allopolyploid Arabidopsis suecica has been explored through isozyme electrophoresis and mutational analysis of chloroplast (cp) DNA. Nuclear encoded isozymes are inherited biparentally and were used to indicate A. thaliana and Cardaminopsis arenosa as parental species. Analysis of the maternally inherited cpDNA provided strong evidence for A. thaliana as maternal parent. The isozyme data suggest multiple origin of A. suecica, because the alloploid shows polymorphisms at the same loci that are polymorphic in its progenitors. The molecular data are in agreement with the hypothesized recent origin of A. suecica at the Late glacial/Holocene boundary in Fennoscandia, in areas opened up by retreating glaciers.