The present investigation was conducted in the Laboratory of Tissue Culture, Horticulture Department, Faculty of Agriculture, Damietta University, Egypt. The objective of this study was to establish a micropropagation protocol suitable for three imported peach rootstocks {Okinawa (P. persica), Nemared (P. persica × P. davidiana) × P. persica) and Garnem (P. dulcis × P. persica)} In vitro. According to the results, soaking the explants in sodium hypochlorite (NaOCl) at 20% for 15 min achieved the highest value of responsive (82.81%) and survived (96.61%) with a minimum value of dead (3.14%) and contaminated (0.24%). Garnem genotype explants had achieved the best response (89.12%) and Survived (90.62%) with minimum dead (0.00%) and maximum contamination (9.37%). The shoot tips showed the highest responsive, Survived, and dead% (100, 87.40 and12.59% respectively) and minimum significant contaminated (0.00%) in comparison with axillary buds. Also, the explants differed significantly in their percentages of responsive, survived, dead, and contaminated at the different collected dates.
The 6-benzylaminopurine (BAP) concentrations used (3 to 5.0 mg/L-1) demonstrated similar behavior in terms of in vitro proliferation, with rates of 3.77 to 6.11, 4.33 to 8.88 and 3.33 to 7.44 shoots per explant for Okinawa, Nemared, and Garnem peach rootstocks respectively, indicating that the number of shoots proliferation is genotype dependent. Moreover, using 5.0 mg/L-1 BAP in combination with 0.2 mg/L-1 IBA produced higher significant values of average shoot proliferation % (96.29%) as well as number of shoots per explant (7.48) and average Leaves number/explant (16.33) than the other treatments. From these results, we could conclude that indole-butyric acid (IBA) synergists with 6-benzylaminopurine (BAP) improved adventitious bud development in vitro multiplication of Okinawa, Nemared, and Garnem peach rootstocks.