ESTABLISHMENT OF AN EFFICIENT In vitro PROPAGATION PROTOCOL FOR RAPID REGENERATION OF APPLE (Malus x domestica Borkh) ROOT STOCK AND SCION VIA NODE CULTURE

Apple (Malus × domestica Borkh) is an important fruit tree grown mainly in temperate regions of the world. In vitro tissue culture is a modern biotechnological application that has been used to improve crop cultivars. Hence, this study was intended to develop optimal micro propagation protocol for selected apple cultivars using nodal explants. The research was arranged in Completely Randomized Design by four replications with factorial arrangement. The collected data was analyzed by SAS software. Apart from 70% Ethanol, NaOCl and HgCl2 in three concentrations was used for surface sterilization. Shoot initiation explants were cultured by using MS basal medium by adding with 0.25 mg/L 0.5 mg/L, 1 mg/L and 2 mg/L of TDZ alone or in mixture with 0.01 mg/L of NAA. MS basal media supplemented with 0.75 mg/L, 1.5 mg/L and 3 mg/L of TDZ alone or in mixture with 1 mg/L of BAP for shoot multiplications. Results obtained from sterilization experiment using 0.3% HgCl2 for 7min showed higher percentage (83.4%) without contamination for M26 root stock. The maximum contamination free and survived explants percentage (66%, 62% and 61.3%) for cultivar Red Delicious, Dorset Golden and Agena local were recorded at 0.2% HgCl2, 2% NaOCl and 0.1% HgCl2 respectively. Related to the control, nearly all levels of hormone treatments had positive effect on all measured parameters. However, of all hormonal treatments, only specific hormone types, concentrations and mixes occasioned better performance in shoot initiation and multiplication(P<0.05). All tested Apple cultivars responded differently to the shooting and rooting treatments. Thus, the findings of this research could be appropriate in in vitro apple plantlet production to encounter the market demand of Apple planting resources.