Associations between myxomycetes, macrofungal fruiting bodies, and fungus-structured detritus in forests and mushroom cultivation

This is the authors' abstract. We don't add key points for this paper.

Myxomycetes (Myxogastria) commonly fruit on decaying organic matter, where they exploit moist, microbe-rich substrates. Macrofungal fruiting bodies and fungus-structured detritus can function as persistent microhabitats that retain moisture and concentrate microbial prey, and may increase opportunities for encounter between myxomycetes and macrofungi. We conducted a structured evidence synthesis of published field records, cultivation reports, and experimental studies to characterise associations between myxomycetes, macrofungal fruiting bodies, and fungus-structured detritus across forest systems and mushroom production environments. The synthesis compiled 45 evidence entries from 38 distinct evidence-bearing sources. Forest reports indicate repeated co-occurrence of myxomycetes with wood-inhabiting macrofungi, including sporocarp formation directly on basidiomata as well as on adjacent, fungus-structured deadwood. Cultivation environments can increase opportunities for contact, and cultivation reports describe fruiting body deterioration or competitive surface colonisation associated with reduced cropping, whereas experimental studies demonstrate attraction of plasmodia to fungal cues, digestion of fungal mycelia in feeding assays, and inhibition of selected fungi by myxomycete secretions in vitro. Overall, the available evidence supports a gradient from shared-habitat associations to context-dependent antagonism. Most records remain descriptive and are better explained by indirect, substrate-mediated coupling than by obligate parasitism.