S04 - Session P1 - New Tools II - Solving hyperhydricity in Tabebuia guyacan by means of lignin precursor p-coumaric acid

Authors: Maroua Grira *, Jean-Paul Reynoird, Romain Martin, Stefaan Werbrouck

The wood of Tabebuia guyacan is very valuable, which is why this tropical tree is threatened by illegal logging. The seeds are becoming rare and therefore in vitro propagation is the only way to propagate this tree in sufficient quantities. A bottleneck during in vitro culture is hyperhydricity, which is responsible for a large percentage loss during acclimatization. P-coumaric acid, a lignin precursor, is known to resolve hyperhydricity in some crops. Lignin is hydrophobic and an increased concentration would cause water to be repelled a little more, away from the intracellular space, to the benefit of the air. The effect of 10, 100, 1000, 10,000 µM p-coumaric acid in the propagation medium of T. guyacan was investigated and the lignin content was analyzed. Also, the percentage of water and air in the intracellular space was determined. 1000 µM coumaric acid did have a positive effect on hyperhydricity: the leaves and stem returned to normal.