Diploids and natural autotetraploids in the predominantly vegetatively propagated Brassica oleracea L. var. ramosa DC and their cytology

Summary Perennial kale is a rare vegetable and forage crop in the Dutch province of Limburg where it is disappearing. It may be a relic of a primitive kale form which could have been grown on a large scale in West-Europe. The crop is predominantly vegetatively propagated.Cytological investigations indicated that a number of accessions are autotetraploid with 2n=4x=36. The origin and age of these autotetraploid accessions are not known, but they may stem from adventitious buds on wounded tissue during the vegetative propagation.