Micropropagation of chokecherry and pincherry cultivars

In vitro culture establishment, shoot proliferation and ex vitro rooting re sponses of chokecherry (Prunus virginiana L.), 'Garrington', and pincherry (P. pensylvanica L.f), 'Mary Liss' and 'Jumping Pound', were examined using various combinations of growth regulators. Dormant winter buds were used a s explants. MSMO medium supplemented with 0.49 muM IBA and either 4.44 or 8 .87 muM BA was found to be optimal for culture initiation of both species a nd cultivars. GA(3) (28.89 muM) significantly reduced (p = 0.0001) the numb er of successfully established cultures. BA concentrations 8.87-12.82 muM S ave optimal shoot proliferation in chokecherry and 4.44 muM BA in both cult ivars of pincherry. Auxin treatments were required for ex vitro rooting of approximately 10 mm long shoots in peat/perlite (1:1 v/v) mixture, at 25 de greesC, under mist. The best rooting (84%) was obtained with IBA/NAA (9.80/ 2.69 muM) A commercial rooting powder, Rootone F, containing IBA/NAA (0.057 /0.067%) mixture, was also effective (75%). The ex vitro rooted plantlets d id not require any additional acclimatization prior to transplanting to the regular greenhouse conditions.