S04 - Session P1 - New Tools I - Could meta-Topoline improve the multiplication and rooting of micropropagated walnut plants - a case study with ‘Lara’ (Juglans regia L.)?

Authors: Lilyana Nacheva *

Persian walnut ( Juglans regia L.) is a very important species as a healthy food and a source of valuable timber. But Juglans are considered amongst the most recalcitrant genera for in vitro culture. The commercial micropropagation and significant breeding efforts for improving marketable traits of walnut is limited because of variable and highly genotype dependent results. The aim of this study was to improve the micropropagation protocol using meta -topolin (mT) instead 6-benzylaminopurine (BAP). An i n vitro culture was maintained on a modified DKW culture medium supplemented with mT (0 -8 μM) or BAP (1.25 μM). Two-stage system for rooting was used n agar solidified medium, supplemented with different concentrations indole butyric acid (IBA) for the root induction and hormone free liquid medium for root elongation. The application of mT in the multiplication nutrient medium stimulated the formation of roots on the rooting stage in J. regia 'Lara' plantlets by achieving 60% rooting.