Tibouchina urvilleana is a very popular small tree or shrub known for its beautiful velvety foliage and violet-blue flowers. It can be used in the mild climate in any landscape or as an indoor container plant in cooler regions. The aim of the present study was to determine the effect of mineral salt composition and growth regulators (BA and IAA) on the growth and development of Tibouchina urvilleana shoots. Shoot tips, obtained from aseptically grown shoots, were cultured on Murashige and Skoog (MS) (full and half strength), Nitsch and Nitsch (NN) or Lloyd and McCown (WPM) media supplemented with BA at 2.5 mg·dm^-3 and IAA at 0.1 mg·dm^-3. Also, the effects of BA (1.0, 2.5, 5.0 mg·dm^-3) and IAA (0.1 or 0.5 mg·dm^-3) applied alone or in combination were investigated. Explants cultured on medium without growth substances were used as a control. The study results showed that the application of full-strength Murashige and Skoog salt mixture has a more beneficial effect on the growth of the main shoot and the induction of axillary shoots of Tibouchina urvilleana compared to ½ MS, WPM and NN salt mixtures. The number of axillary shoots increases with the increasing concentration of BA (from 1 to 5 mg∙dm^-3), but they are characterized by a smaller length. The combined application of BA and IAA does not have a significant effect on the induction of axillary shoots. The addition of IAA at a concentration of 0.5 mg∙dm^-3 to the media containing BA (1 to 5 mg∙dm^-3) has a beneficial effect on elongation growth of axillary shoots.

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