Comparative analysis of hexaploid Avena species using REMAP and ISSR methods

Taxonomic relationships in Avena genus are not evident. Avena sativa L. might have originated either from Avena sterilis L. or Avena fatua L. Alternatively, it may have evolved independently during formation of the hexaploid form. A. fatua may have a different A genome than the other hexaploids. Studies performed with Ty1-copia retrotransposon probes demonstrated that this retrotransposon is present at low copy number in the C genome, while it is abundant in A, B, and D. The observed differences provide an opportunity for analyzing the putative origin of A. fatua as well as its relationships with other hexaploids. Two marker systems were applied. Retrotransposon-microsatellite amplified polymorphism (REMAP) was used to obtain evidence that the A genome of A. fatua has a different origin than the other hexaploids, and inter-simple sequence repeat (ISSR) was applied to screen for whole genome polymorphisms. The results tend to favor the hypothesis that A. sterilis could be the progenitor of A. sativa and A. fatua and showed that A. fatua could not have originated via cross with a maternal species having a different A genome than A. sterilis and A. sativa.