Effect of Mesos Components (MgSO, CaCl, KHPO) on In Vitro Shoot Growth of Blackberry, Blueberry, and Saskatoon.

Berry fruit species are, in many countries, considered biologically and economically valuable and important species of small fruits. The aim of this work was to examine the influence of either decreased or increased mesos concentrations (MgSO, CaCl, and KHPO) on shoot multiplication of five cultivars of three small fruit species ( var. , 'Black Satin' and 'Loch Ness', and 'Brigitta Blue' and 'Toro'). Mesos nutrients were manipulated from half to four times their base concentration. The results indicate that mesos manipulation significantly influences the number and length of shoots in most of the studied cultivars. The greatest multiplication rate for was achieved with tripled mesos, whereas 'Black Satin' and 'Loch Ness' reacted positively to a lower (1-2x) concentration of mesos. Decreasing the concentration of mesos to half led to worse quality in both blackberry and Saskatoon shoots. 'Brigitta Blue' was more sensitive to greater mesos concentrations compared to 'Toro'. Optimizing the mineral nutrition of plants cultivated in vitro enhances their multiplication rate and contributes to a higher production of good quality plantlets.