Potential spread of forest soil-borne fungi through earthworm consumption and casting

To test if forest soil-borne fungi concerned with plant health can be selectively dispersed by earthworms, 10 fungal species isolated from 5 forests were presented at 2 concentrations to 3 ecologically distinct earthworm species in laboratory trials. Between 5 and 13 days after introduction, casts were collected (where possible) from each earthworm species fed with a different fungus. These casts were analysed using molecular methods for the presence of the given fungus and its vitality verified through traditional plating techniques. The research confirmed that earthworms have an important role in dispersal of soil fungi in forests, and that such activity can depend on the taxonomical position of the fungus, ecological category of the earthworm species involved and the fungal concentration. In certain instances there is a suggestion that some fungi may be toxic to some earthworms at the given concentrations, which equated to those within and outside of the rhizosphere.