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The present research carried out to compare in vitro rooting as well as shoot proliferation and elongation of Pyrus betulaefolia shoots after infecting basal part with Agrobacterium rhizogenes suspension strain DSM 30200 and vitamin B₁₂ at either 1.0 or 1.5 mg/L and two combinations between them. Untreated control micro-cuttings failed completely to induce adventitious roots. Otherwise, Agrobacterium rhizogenes inoculation treatment gave the best in vitro effect on rooting performance and root parameters of the treated micro-cuttings. Addition of antioxidant (vitamin B₁₂) at 1.0 and 1.5 mg/L to culture medium showed positive effects on rooting formation and root parameters with special emphasis to the concentration of 1.5 mg/L. This later treatment, among the examined ones, recorded the earliest start rooting (10.33 days) and the highest value of explants survival and rooting percentages (50 and 50.33%, respectively). As for shoots proliferation and elongation parameters, it showed the better response than the applied 1.0 mg/L “T₂” in most measured parameters and it occupied the next rank after A. rhizogenes inoculation treatment “T₁” in that respect. In contrast, the combined treatments failed completely to induce adventitious roots and recorded the lowest levels of shoot multiplication and elongation parameters on the treated micro-cuttings.