PHENOLIC-ACIDS IN HEALTHY AND INFECTED-LEAVES OF ZOSTERA-MARINA AND THEIR GROWTH-LIMITING PROPERTIES TOWARDS LABYRINTHULA-ZOSTERAE

Using high-performance liquid chromatography, we found four phenolic a cids (gallic, caffeic, p-coumaric and ferulic acid) to be present in l eaves of Zostera marina L. from Roscoff, France. Comparison of the con centrations in healthy leaves and leaves infected with Labyrinthula zo sterae Porter and Muehlstein (assumed to be the biological agent of wa sting disease) showed a sharp increase of especially caffeic acid in i nfected leaves. Bioassays give indications that caffeic acid, present in the concentrations as measured in infected leaves, influences the g rowth of Labyrinthula. (C) 1997 Elsevier Science B.V.