AbstractEight Rubus genotypes (the red raspberry (R. idaeus) cultivars Autumn Bliss, Glen Moy, Glen Clova and Glen Prosen, the blackberry (R. fruticosus) cultivars Loch Ness, Chester and Hull Thornless, and the red raspberry-blackberry cross Tayberry) were examined for their ability to regenerate on 55 media differing in their plant growth regulator content. Regeneration was obtained from all cultivars examined, though efficiency varied greatly depending on genotype. A minimum threshold level of thidiazuron was found to be required for regeneration from leaf discs, and the optimum level for efficient regeneration varied among cultivars. Zeatin was not found to be as effective. Thidiazuron supplemented with a range of individual auxins was investigated, and it was found that NAA had a complementary effect, applicable across a wide range of cultivars at relatively low levels. Using five random primers, 28 polymorphic PCR amplification products (RAPD markers) were stably generated and used to discriminate all eight genotypes investigated. A similarity matrix and dendrogram was generated from the markers and this was related to their regenerative ability.