The Effects of Some Phenolic Compounds Upon the Growth of Two Species of Phytophthora

Abstract

The effects of the addition of 26 phenolic compounds at three concentrations-O.S mM, 1.0 mM, and 2.0 mM-to liquid basal media, JPon the growth of Phytophthora cactorum (Leb. and Cohn) Schroet. and Phytophthora parasitica Dast., were determined. In general, the growth responses of the two fungi were similar. The toxicity of the compounds can be related to their structural formulae. Compounds with a hydroxyl group in the ortho position were more inhibitory than those with the hydroxyl group in the para position. The presence of additional hydroxyl groups reduced the inhibitory effect. Compounds with one methoxyl group were more inhibitory than those with two. Chlorogenic acid, an important naturally-occurring polyphenol, had l ttle effect upon the growth of either fungus. Cinnamic acid inhibited the growth of both fungi mare than any other compound. © 1965 Taylor & Francis Group, LLC. All rights reserved.