Optimization of the protocol for in vitro propagation of autochthonous plum genotype ‘Metlaš’

Abstract

Fast and cost-effective clonal propagation of planting material is possible to achieve by application of tissue culture in vitro. In this way, problems associated with traditional propagation, such as rapid spreading of diseases, lack of initial material caused by dependence on seasonal growth or low propagation coefficient can be overcome. This paper deals with optimization of micropropagation of autochthonous plum ‘Metlaš’ (Prunus domestica L.) originated from Guberevci (Municipality Knić, Serbia). ‘Metlaš’ is very often considered to be the same genotype as ‘Okruglica’ (syn. ‘Dragačica’), but they can be clearly distinguished according to plant habit, stone and fruit characteristics. To optimize multiplication stage, the influence of benzyladenine (BA at 0.5, 1.0, 1.5 and 2.0 mg/l) and thidiazuron (TDZ at 0.25, 0.5, 1.0 and 1.5 mg/l) on the multiplication capacity (multiplication index, length of axial and lateral shoots) was examined. Rooting ability of shoots (rooting rate, number and length of roots, and height of rooted plants) was monitored on half strength Murashige and Skoog (MS) medium containing 1.0 mg/l indole-3-butyric acid (IBA) or 1-naphthaleneacetic acid (NAA), each combined with 0.1 mg/l gibberellic acid (GA3). TDZ applied at 0.25 mg/l gave the highest multiplication index (9.1), while the longest axial (14.1 mm) and axillary shoots (8.6 mm) were obtained on medium with 1.5 mg/l BA. Although both auxins proved to be efficient in rhizogenesis (rooting rates being 85.7% and 95.2%), higher values of all rooting parameters were observed in the presence of IBA. Rooted shoots were successfully acclimatized.