Food choice of fungus-feeding Collembola and fungal defence against Collembola

Abstract

Fungal defence against mushroom-feeding Collembola was studied. Field observations and experiments showed that the mushroom-feeding collembolan Ceratophysella denisana chooses food fungus species based on its preference for fruiting bodies, suggesting that fruiting body characteristics affect food choice by C. denisana and may play roles in fungal defence. Further observations suggest that C. denisana potentially reduces fungal fitness by damaging spores, rather than increasing fitness by dispersing spores via gut passage. In the ascomycetes Ciborinia camelliae and Spathularia flavida, repulsion of C. denisana by fruiting bodies in response to injury has been discovered. The bioactivity is suspected to be involved in food avoidance of C. denisana and defence by the ascomycetes. In the basidiomycetes Russula bella and Strobilurus ohshimae, we found that their cystidia are capable of killing C. denisana on contact and can act as a defence by reducing attacks of C. denisana on spore-bearing gills.