The influence of different concentration of cytokinin (BA) and auxin (IBA) on in vitro multiplication of two plum cultivars

This research focused on two domestic plum cultivars, ‘Timočanka’ and ‘Boranka’, aiming to optimize the multiplication stage across ten different media. The study examined the influence of benzyladenine (BA at concentration of 1.0, 1.125, 2.225 and 3.335 mg l-1) and indole-3-butyric acid (IBA at concentration of 0.0, 0.1, and 0.5, mg l-1) on the multiplication capacity. The evaluated parameters included the multiplication index, length of axial and lateral shoots, and number of leaves of both shoot types, as well as fresh and dry weight (FW and DW) of shoots (axial and lateral shoot in total) and callus. For ‘Timočanka’, BA applied at 1.125 mg l-1 gave the best results in mention parameters, with multiplication index of (4.2). In contrast, significant differences in assessed parameters were less evident for ‘Boranka’. Therefore, advanced statistical methods, including Z-score normalization and principal component analysis (PCA), were applied to further investigate the correlation between medium composition and multiplication parameters. Both PCA and Z-score normalization confirmed the positive effect of media with higher BA concentration in the absence of IBA on the multiplication capacity of ‘Boranka’.