Micro-propagation of olive provides the possibility of mass production true to type plants with appropriate attributes in short period of time, compared to conventional methods. Micropropagation of olive requires optimization of protocols adapted to specific cultivars requirements. This experiment was carried out during 2020 and 2021 seasons in tissue culture laboratory of Pomology Department, Faculty of Agriculture, Cairo University in order to evaluate the potential effects of Nano silver at

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... , 5, 10 and 20 mg L -1 to improve sprouting percentage and shoot growth of Picual olive cv. The effect of nutrient media composition (MS modified, OM and OM modified) and cytokinins (BAP and Zeatin) on multiplication rate and shoot growth were examined. IBA and NAA (2 and 4 mg L -1 ) were examined during rooting stage. The obtained results cleared that silver Nanoparticles (AgNPs) at 5 mg L -1 recorded the highest percentage of bud sprouting, shoot length, number of shoots/explant and number of leaves/ shoot. Olive medium (OM) recorded the highest shoot length, number of shoots/explant and number of leaves/ shoot compared with OM modified and MS modified media. Also, Zeatin at 4 mg L -1 recorded the highest shoot growth parameters during in vitro multiplication stage. During in vitro rooting stage, both the type and concentration of auxins have a significant influence on number of roots, root length and rooting % of Picual olive cultivar. In conclusion, it is recommended that very low concentrations of Nano silver particles to be used in plants tissue culture on olive media (OM) supplemented with Zeatin at 4mg L -1 .