Diversity for enzymes, flowering behaviour and purple plant colour of perennial kale (Brassica oleraceae L. var. ramosa DC) in the Netherlands.

Perennial kale has probably been domesticated and distributed by the Romans. Some relic populations are still being grown in various parts of western Europe (Ireland, Scotland, England, the Netherlands, Belgium, France, Portugal), in Ethiopia, in Brazil and Haiti up to the present. Most accessions of perennial kale grown in gardens in the Dutch province Limburg have lost their flowering ability. Some of them flower occasionally, others every year. No explanation can be given for this inconstant behaviour. This predominantly diploid material is quite uniform for the enzymes acid phosphatase (ACD), esterase (EST), glutamate oxaloacetate transaminase (GOT) and shikamata dehydrogenase (SKD). The same is true for presence of anthocyanins in the leaves. The 40 fully investigated accessions could be grouped into 8 phenotypes: 26 with phenotype 1 (at least 9 are tetraploid), three with phenotype 2, six with phenotype 3, and one for each of the phenotypes 4 to 8. Accessions with phenotypes 2 and 3 had the same phenotype for the four enzymes as phenotype 1, and so have most of the 13 accessions, only investigated for enzymes.