S04 - Session P1 - New Tools I - Meta-topolin riboside and dikegulac for improved micropropagation of olive (Olea europea L.)

Authors: Saba Taheri*, Isaac Kofi Bimpong, Shoba Sivasanka, Stefaan P.O. Werbrouck

Olive ( Olea europaea L.) is one of the most profitable fruit trees in the Mediterranean, due to its numerous harvestable products such as oil, wood and fruit. Its cultivation is severely plagued by the bacterial disease Xylella fastidiosa. Micropropagation could allow the rapid introduction of new resistant selections. Olive in vitro plants are characterised by a strong apical dominance that makes branching virtually impossible and thus limits the potential for micropropagation. We used the widely cultivated cultivar 'Arbequina'. To increase the proliferation rate, we combined 5 µm zeatin or meta-topolin riboside with 0.088 mM sucrose or mannitol and 10 or 20 µM dikegulac in Rugini's Olive Medium. Dikegulac is used in the field to break dormancy and promote branching in woody crops. We showed that mTR was as good as the classically used and very expensive zeatin and that the relatively expensive mannitol was no improvement. Dikegulac was slightly phytotoxic but had a branching effect in decapitated shoots.