Amanda Currie, Alan Gange, Philip Murray

Arbuscular mycorrhizal (AM) fungi are ubiquitous in ecosystems, but the vectors which enable their dispersal are poorly known.  As the majority of these fungi sporulate in soil or within roots, it seems likely that subterranean invertebrates must play a major role in the dispersal process.  While there is some evidence that earthworms are important, the effect which subterranean insects have on dispersal is virtually unknown.

In this paper, we outline examples of subterranean insects which can potentially disperse mycorrhizal inoculum, through their feeding activities on roots.  Field and laboratory studies will be described which have been designed to investigate whether these insects can disperse inoculum, and if they do, whether the fungi can remain viable after passage through the digestive system of the insects.

The evidence suggests that chafer larvae (Coleoptera: Scarabaeidae) and crane fly larvae (Diptera: Tipulidae) may be important vectors of AM inoculum.  Chafers have been studied in several long-term improved grassland sites in southern England and tipulids in the NERC Soil Biodiversity site at Sourhope, Scotland.  Spores of AM fungi and colonized root fragments have been found within these larvae and in some cases these have successfully initiated colonization in plant roots.