Soil microorganisms and phenolics: Their implication in spruce natural regeneration failure.

Among other factors, allelopathy due to phenolics is a cause of natural reg eneration deficiency in subalpine spruce (Picea abies L. Karst.) forests. T urnover of these allelochemicals in soil with and without microorganisms is reported herein. Microflora not only appeared to be able to metabolize som e aromatic compounds naturally occurring in soil (p-hydroxy-benzoic and van illic acids) but also being able to synthesize other molecules (ferulic and p-coumaric acids), probably by means of lignin degradation. Thus, results presented in this study suggest to pay attention to soil microorganisms in order to decrease the allelopathic potential and to improve natural regener ation.