In Vitro Propagation of Ottawa 3 Apple Rootstock

Methods were developed for obtaining normal shoot cultures and for rapid in vitro proliferation and rooting of Ottawa 3 apple rootstock from meristem tips. The presence of naphthalene acetic acid (NAA) and benzyladenine (BA), both at concentrations of either 0.5 or 1.0 mg/L in the culture medium, was most effective for in vitro shoot proliferation, but growth was abnormal. Normal growth was achieved when shoots were cultured with a combination of 0.5 mg/L NAA, 0.5 mg/L BA and 5.0 mg/L gibberellic acid. One hundred percent rooting was achieved after 2 wk on agar medium supplemented with 6.25 mg/L indole butyric acid.