Soil fungi are important food resources for soil fauna. Here we ask whether the collembolan Folsomia
candida shows selectivity in grazing between four saprophytic fungi (Penicillium chrysogenum, Penicillium
expansum, Absidia glauca, and Cladosporium herbarum), whether grazing preference corresponds to
effects on collembolan reproduction, and whether the effects of fungi on grazing and reproduction
depends on the fungal substrate, which included three kinds of litter (Alnus glutinosa, Salix caprea, and
Quercus robur) and one kind of agar (yeast extract). On agar, C. herbarum and A. glauca were the most
preferred fungi and supported the highest collembolan reproduction. On fungal-colonized litter, grazing
preference was more affected by litter type than by fungal species whereas collembolan reproduction
was affected by both litter type and fungal species. On fungal-colonized litter, the litter type that was
most preferred for grazing did not support the highest reproduction, i.e., there was an inconsistency
between food preference and suitability. Alder and willow were preferred over oak for grazing, but alder
supported the least reproduction.