Veränderte Wundreaktion in der Apfelrinde durch Phytophthora-Exsudate

The aim of this study was to evaluate the effect of elicitins in the culture filtrates on the phenylproanoid metabolism and the live status of cells in apple bark tissues. Trees, genotype MM106, were wounded at stem base with a cork borer and a filter paper saturated with culture filtrates of Phytophthora citricola and Phytophthora quercina was inserted. The content of flavan-3-ols and proanthocyandins decreased with the increasing concentration of the solution. As a reaction to wounding phenolics accumulated in the surrounding zone. Changes in the phenylpropanoid metabolism, but no change in necrosis development as seen in tobacco and tomato, were observed. A direct protective effect of flavan-3-ols and proanthocyanidins against fungal elicitins is discussed.