A Reliable Protocol for Adventitious Shoot Regenerationin GF677 and Rabi Cultivar, a Late Flowering Almond

In vitro leaf explants of GF677 hybrid rootstock and Rabi cultivar were placed on MQL medium supplemented with BAP at 0, 1, 2, 3 and 4 mg/L and NAA at 0, 0.15 and 0.3 mg/L concentrations. The results revealed that BAP, NAA, genotype and their interactions had significant effect on both percentage and mean number of the regenerated shoots. For GF677, the highest percentage of shoot regeneration (44 ± 1.74)and mean number of shoots (2.64 ± 0.10) were obtained using 3 mg/L BAP without NAA. However, there were no significant differences among treatment combinations of BAP and NAA with regard to the Rabi cultivar. Furthermore, for GF677 and Rabi genotypes, using NAA at 1 mg/L produced the highest rooting rate (60 and 75%, respectively) and number of roots per shoot (1.85 ± 0.47 and 2.4 ± 0.46, respectively) when the shoots were maintained in the dark on the rooting medium for 10 days before transferring to a 16/8 h photoperiod. In total, 90% of the plantlets survived during acclimatization phase in the greenhouse.