Micropropagation of Cold Resistant Blackberry Cultivar 'Gazda'

Abstract

Blackberries are some of the most consumed berries in the world. Areas planted with blackberry in Europe and especially in Romania are limited mainly due to low frost resistance of traditional varieties. One of the most frost resist ant cultivar, suitable for cold Romanian winters, i s the variety 'Gazda'. Due to several drawbacks of the co nventional propagation of this cultivar when using root cuttings, the efficiency of a micropropagation protocol was tested, in order to obtain high quali ty planting material. For the in vitro culture establishment axillary dormant buds were i ncubated on MS medium supplemented with BAP. Proliferation of the regenerated shoots was tested on MS and DKW media using different concentrations of plant growt h regulators: BAP, 4-CPPU and Zeatin. BAP caused average proliferation rates but also generat ed large masses of basal callus. 4-CPPU was the solely plant hormone that did not generate severe c allus at any concentration and also provided the highest proliferation rate. It was also tested the callus induction potential from in vitro obtained leaves using 15 hormonal variants (5 hormone types in diff erent concentrations). For most variants it was achieved a substantial mass of callus, however no d irect regeneration was obtained. In vitro plantlets were successfully rooted and acclimatized directly ex vitro in Jiffy-7 pellets.