Evaluación de metatopolina en micropropagación de genotipos de eucalyptus globulus

The objective of this thesis was to evaluate the effect of two cytokinins in Eucalyptus globulus individuals in the micropropagation process, focusing on the multiplication and rooting phases. For the multiplication phase, the study evaluated shoot proliferation, height growth, callus production and vitrification in explants, while in the rooting phase the study focused on determining rooting percentages and root length. Four genotypes and five treatments were used for the experiment, depending on the type and concentration of cytokinin supplied in the multiplication phase.

In the multiplication phase, the explants were subcultured every four weeks for a period of 3 months. The results indicated that the supply of cytokinins is necessary in the multiplication phase, since without, are obtained small explants, with low proliferation and with a high incidence of calluses in leaves and apex. The explants from Mt1 treatments turned out to be superior in height, as it was the only treatment that differed from the control for the three height intervals studied. Comparatively, the explants obtained from Ba1 resulted in a lower height than the Mt1 explants.

To evaluate the variables of the rooting phase, the explants were transferred to rooting media for three weeks. The results showed that treatment without cytokinin registered low rooting percentages (6,3%), due to poor explant conformation in the multiplication phase. The treatment with Mt1 obtained the highest rooting percentages (39,0%) and root length, and the 19G40 genotype presented the highest rooting percentages (45,8%), being the only genotype that rooted in all treatments. In turn, the 19G40-Mt1 combination presented the highest rooting percentage, 93%.