posted on 2004-08-25, 00:00authored byJörg Storsberg, Hartwig Schulz, Michael Keusgen, Fadi Tannous, Klaus J. Dehmer, E. R. Joachim Keller
Interspecific hybridization between wild and cultivated species of the genus Allium has been performed
to generate plant material possessing biochemical properties of both parental plants. These cross-breeding experiments should lead to Allium plants with higher amounts of valuable constituents. The
chemical characterization of interspecific hybrids between A. cepa and A. kermesinum is described
on the basis of their sulfur-containing constituents and secondary metabolites. In addition, the hybrid
character has been proven by random amplified polymorphic DNA (RAPD) analysis of the progenies
obtained from the crosses. It has been shown that the distribution of the cysteine sulfoxides as well
as the volatile secondary metabolites in the hybrids is not uniform. The profiles are mainly determined
by the paternal wild species A. kermesinum. It has been ascertained that the gas chromatography
profiles of the hybrids show increasing amounts of unsymmetrical substituted oligosulfides, which
are known to be physiologically active substances. On the basis of statistical calculations, three
different types of hybrids can be separated. The chemical analysis of cysteine sulfoxides and volatile
sulfur-containing substances is shown to be a useful tool for breeding purposes as it allows an effective
selection with regard to optimal distribution and amount of valuable constituents.
Keywords: Allium hybrids; RAPD analysis; SPME-GC analysis, cysteine sulfoxides; aroma profiles