The organic acid composition of Calluna heathland soil with special reference to phyto- and fungitoxicity - I. Isolation and identification of organic acids

Abstract

A number of 'free' phenolic and simple fatty acid compounds of potentially high phytotoxicity have been isolated from Calluna heathland soil and identified by GC and GC-MS methods. Amongst these the aromatic acids o-hydroxybenzoic (salicylic), p-methoxybenzoic and benzoic acid are reported for the first time in 'free' form in soil, as are the fatty acids octanoic (caprylic), and decanoic (capric) acid both of which occur mostly in the hydroxy form. These short chain (C8 and C10) acids are known to have particularly strong phytotoxic properties. Hydroxynonanoic (pelargonic) acid was also extracted and identified. In addition to being phytotoxic these compounds have strong fungitoxic properties. Their potential effects in Calluna heathland soils are discussed from a physiological and ecological viewpoint. © 1983 Martinus Nijhoff/Dr W. Junk Publishers.