THE INFLUENCE OF THE HERBICIDE GLYPHOSATE ON INTERSPECIFIC INTERACTIONS BETWEEN 4 SOIL FUNGAL SPECIES

The influence of the herbicide glyphosate on two-way interactions between four fungal species was investigated on agar using direct opposition, volatile inhibitor and non-volatile inhibitor tests, and on barley straw using tests for competitive saprotrophic ability. The results indicated that glyphosate was often capable of shifting the direction of two-species interactions, but there was little agreement between the different tests. Reanalysis of particle colonization data presented earlier demonstrated that glyphosate frequently eliminated negative associations between the same four species, possibly by acting as a resource. It is concluded that interactions between pairs of fungi can be influenced directly by glyphosate (especially at high concentrations) and that this may influence soil fungal community structure.