Genetic fidelity evaluation of micropropagated Malus cultivars and rootstocks

Ex vitro and in vitro apple (Malus domestica Borkh., cvs. Fiorina, Idared, Rebra, Goldrush, Romus3, Romus4 and the rootstocks M9 and M26) plants were selected to assess donal fidelity by RAPD markers. In vitro cultures were grown on Murashige and Skoog (1962) medium supplemented with Lee and De Fossard (1977) vitamins, 1.2 mg l⁻¹ N⁶-benzyladenine (BA), 0.004 mg l⁻¹ -naftil-acetic acid (NAA), 30 g l⁻¹ dextrose and 7 g l⁻¹ agar. The plants were grown at 24°C under a 16 hr light photoperiod with a light intensity of 40 mmol m⁻² s⁻¹ photosynthetic active radiation (PAR). Subcultures were performed every four weeks. Genomic DNA isolated from the mentioned cultivars and rootstocks was amplified using four different unspecific primers (OPB 04, OPB 07, OPB 17, OPF 04) ranging between 9 and 10 nucleotides. No significant variations among micropropagated plants on the basis of RAPD markers in comparison with the genetic profile of the corresponding ex vitro donor plants were detected.