What does the published scientific research say about Laccaria laccata?

Eight PubMed records index Laccaria laccata — also known as Agaricus laccatus, Clitocybe laccata, and Omphalia laccata — in a plant-input context. Research documents this ectomycorrhizal fungus forming associations with Pinus sylvestris, Eucalyptus diversicolor, Pinus pinaster, and Casuarinaceae hosts including Allocasuarina littoralis and Casuarina equisetifolia.

Multiple rhizosphere studies report L. laccata mantle hyphae suppressing competing soil fungi — Trichoderma virens, Trichoderma harzianum, and Mucor hiemalis — through coiling, inhibition, and hyphal degradation in vitro. On mycorrhizal Pinus sylvestris roots, germination of T. virens conidia and Mucor sporangiospores was substantially reduced or blocked in these laboratory investigations.

In Eucalyptus diversicolor pot trials, L. laccata inoculation produced the largest growth response among four tested ECM fungi, with effects strongest at low phosphorus supply. Mycorrhizal infection is reported in the peer-reviewed literature to increase phosphorus content in plant tissues at sub-optimal soil P levels.

A greenhouse nursery experiment found that a fungal mixture including Laccaria laccata improved Pinus pinaster seedling growth and nutrition without added chemical fertilizer. The Douglas fir/L. laccata ectomycorrhizal pairing is also cited in the literature as a reference system for research on mycorrhization helper bacteria.