CROP IDENTIFICATIONS OF SOME BRASSICA OLERACEA CULTIVARS

Among the different cole crops (Brassica oleracea L.) to have been derived from the wild forms of the species by artificial selection and hybridisation are 'savoy' (var. bullata DC. et var. sabauda L.) and 'cabbage'. They are distinguished uished from each other in that 'the leaves of savoy are puckered or rugose and the head is generally less compact' (Wellington and Quartley, 1972). Cabbage is considered to comprise two cultivar groups namely 'white cabbage' (f. alba DC.) and 'red cabbage' (f. rubra L.). White cabbage has 'green outer leaves and white inner leaves' whereas red cabbage has 'outer leaves which are red or purple and red inner leaves' (ibid.).

The cultivars which belong to each of the three groups savoy, white cabbage and red cabbage are listed in the EC Common Catalogue of vegetable species (Anon., 1984). While most are deemed to have been correctly listed the crop identifications of some are less certain. These are cultivars intermediate in morphology between savoy and white cabbage eg 'Tundra', 'January King', 'Clipper' and also cultivars listed as savoy eg 'January King' or white cabbage eg 'Late Purple Flat Poll' which, because of the presence of anthocyanin pigmentation, bear some resemblance to red cabbage.

This paper reports on the use of numerical methods to re-examine the crop identifications of 17 'intermediate' cultivars. Sixteen cultivars were intermediate between savoy and white cabbage. On the basis of the sum of the means of the diagnostic characters and the results of a principal components analysis one was identified as savoy and 15 as white cabbage. Twelve of the 15 had previously been identified as savoy. Ten cultivars were intermediate between savoy or white cabbage and red cabbage but none was identified as red cabbage. The degree to which the intermediate cultivars extend the crop definitions is described and the implications discussed.