Construction of intergeneric somatic hybrids between Brassica oleracea and Armoracia rusticana

Abstract

Somatic hybridization of Brassica oleracea (cauliflower, cabbage, kohlrabi) and Armoracia rusticana (horseradish) protoplasts was performed to test the possibility of the formation of intergeneric hybrids. Out of three B. oleracea crops tested only cauliflower (B. oleracea var. botrytis) yielded viable hybrids when fused with horseradish protoplasts. Regenerated plants were asymmetric hybrids as revealed by morphological, karyological, and DNA analysis. In these plants, extensive elimination of A. rusticana genome occurred during subsequent cultivation. Using a chloroplast DNA probe no A. rusticana-specific hybridization signals were detected thus indicating a rapid elimination of horseradish cytoplasmic (chloroplast) components.