Flavor and odour characteristics of species of Allium in relation to their capacity to stimulate germination of sclerotia of Sclerotium cepivorum.

Of many species or cultivars of Allium tested only six ornamental species showed little or no capacity to stimulate germination of sclerotia of Sclerotium cepivorum. All six species had S-methyl-L-cysteine sulphoxide as their principal flavour and odour precursor and their overall flavour and odour levels were low. All other species and cultivars were highly stimulatory, contained considerahle amounts of S-1 or S-2-propenyl-L-cysteine sulphoxide as flavour and odour precursors and, with a few exceptions, they possessed high overall flavour and odour levels. These included several species which are thought to be related to cultivated edible forms. With the possible exception of A. caeruleum and A. cyaneum no evidence of resistance to infection by S. cepivorum was detected.