Amy Treonis, Roger Cook, Amanda Currie, Lorna Dawson, Alan Gange, Sue Grayston, & Phil Murray

Root feeding organisms, such as insect larvae and plant-parasitic nematodes, can consume significant amounts of plant material, and their control can be a considerable expense in many agricultural systems, including upland grassland.  However, despite the potential of belowground herbivory as a key ecological interaction, little research has been done to examine the effects of root feeding on soil biodiversity and nutrient cycling.  As part of the U.K.'s Soil Biodiversity Thematic Programme, we are studying the diversity and interactions between invertebrate root feeders (insect larvae, nematodes) and soil microbial communities in both field and laboratory studies.  Our results suggest that root feeding may lead to changes in patterns of rhizodeposition and root turnover that impact on rhizosphere carbon flow and soil microbial diversity and functioning.  Furthermore, these effects also have been found to be plant species specific.  In terrestrial ecosystems, root herbivory may indirectly regulate the structure and activity of the soil microbial biomass.