Genetic stability of cultured hairy roots induced by Agrobacterium rhizogenes on tuber discs of potato cv. Bintje

Agrobacterium rhizogenes induced hairy roots on discs of the tuber tissue of the tetraploid potato cv. Bintje after infection. Early and late generated hairy roots (transformed roots) were excised directly from the tuber discs and analysed for genetic stability by chromosome counts and determination of nuclear DNA content with flow cytometry. Another part was cloned by subculturing on MS-medium without hormones and subsequently analysed. Twenty-one of the 27 primary hairy roots and all 16 subcultured hairy roots were tetraploid thus suggesting genetic stability of transformed roots. Shoot regeneration was observed on hairy roots and therefore, it is suggested that A. rhizogenes transformation can be a suitable system for genetically stable plant regeneration from transformed cells.