Cultural Studies On Soil Nematodes and Their Fungal Hosts

Abstract

In laboratory experiments survival, feeding and reproduction of nematodes in cultures with mycorrhizal and saprophytic fungi were investigated. Nematodes extracted from the organic layer of a spruce forest soil were inoculated to fungal plates. The fungal feeder Aphelenchoides saprophilus was the most successful species to multiply. With mycorrhizal fungi as a food source its population developed faster and to a greater extent than it did with saprophytic fungal species. The grazing of A. saprophilus reduced mycelial weight and fungal growth rate. Similar effects are likely to occur in the field, and can influence mycorrhizal development or affect competition between soil fungi. Besides A. saprophilus, the saprophagous nematode Acrobeloides nanus reproduced well in cultures with mycorrhizal fungi. There may be an element of substrate ingestion or grazing on fungal hyphae for some bacterial feeding nematodes.