Institute of Bioanalytical Sciences

Untersuchungen zur antifungalen Wirkung der Wurzelextrakte und Fraktionen aus Rheum rhabarbarum L. gegenüber dem Pflanzenpathogen Phytophthora capsici Leonian am Modellsystem Tomate

Angefertigt von: Loreen Sommermann

  1. Gutachter: Prof. Dr. Ingo Schellenberg
  2. Gutachter: Dr. Helmut Baltruschat

Subject of this master thesis was to test the antifungal effect of obtained fractions of rhubarb extract against Phytophthora capsici. In addition to that, the composition of the substances contained in those fractions were analyzed to derive a correlation between their antifungal activity and their structure. In order to achieve that, a model system of tomato (as host) and Phytophthora capsici has been established at the Institute of Bioanalytical Sciences. The antifungal assays have been investigated using a leaf segment test. According to this system, leafs were inoculated with a zoospore suspension of Phytophthora capsici and later the infected parts were estimated. Depending on these tests, the fractions have been analyzed for typical substances contained in Rheum spp. The literature part gives a review about Rheum spp., Phytophthora capsici and the fundamentals of the used methods. The third part of this thesis, holds information about these methods and their parameters. The results of the antifungal activity as well as the analyzed substances of the fractions are described in the fourth part in more detail. In combination with the above-mentioned studies, the results were derived and discussed concerning the antifungal activity. The final part of the thesis is a summary of this thesis as well as a prospect of subsequent investigations related to this topic.