Phenolic Compounds in Roots and Leaves of Four Citrus Cultivars

Abstract

As part of an investigation of the biochemical changes associated with the decline of citrus trees caused by the burrowing nematode, Radopholus similis (Cobb) Thorne, a study was undertaken on the isolation of growth promoters and inhibitors in both the roots and young branch terminals. Since a number of phenolics have been identified as co-factors for indolyl-3-acetic acid (IAA) oxidase¹, a better understanding of the type of growth associated with citrus decline would involve information concerning possible changes in the phenolic constituents. Another reason for consideration is the participation, if any, of phenolics in host resistance either prior to or after pathogenesis. This portion of the investigation is concerned with the extraction, chromatography and identification of the free and acid hydrolysable (bound) phenolics in the leaves and roots of 4 citrus cultivars.