Fungal decomposers of leaf litter from an invaded and native mountain forest of NW Argentina

Abstract

The impact of plant species invasions onthe abundance, composition and activity of fungaldecomposers of leaf litter is poorly understood. In thisstudy, we isolated and compared the relative abundanceof ligninocellulolytic fungi of leaf litter mixturesfrom a native forest and a forest invaded byLigustrum lucidum in a lower mountain forest ofTucuman, Argentina. In addition, we evaluated therelationship between the relative abundance ofligninocellulolytic fungi and properties of the soil ofboth forest types. Finally, we identified lignin degradingfungi and characterized their polyphenol oxidaseactivities. The relative abundance of ligninocellulolyticfungi was higher in leaf litter mixtures from thenative forest. The abundance of cellulolytic fungi wasnegatively related with soil pH while the abundance ofligninolytic fungi was positively related with soilhumidity. We identified fifteen genera of ligninolyticfungi; four strains were isolated from both forest types,six strains only from the invaded forest and five strainswere isolated only from the native forest. The resultsfound in this study suggest that L. Lucidum invasioncould alter the abundance and composition of fungaldecomposers. Long-term studies that include ananalysis of the nutritional quality of litter are needed,for a more complete overview of the influence ofL. Lucidum invasion on fungal decomposers and onleaf litter decomposition.