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Wood residues from forestry industries can be potential raw materials for specialty and edible mushroom production. The aim of this study was to evaluate the suitability of wood residues for the cultivation of Ganoderma lucidum originating from boreal forests. The substrates tested included sawdust and wood chips of Betula spp., Populus tremula, Picea abies, Pinus sylvestris and Larix sp. The suitability of the substrates and the ability of the strains to develop fruiting bodies and produce β-glucan were evaluated. Fruiting body formation was supported by applying two different cold shock treatments to substrate bags. The highest yields were observed with MUS192 strain and Betula spp. and P. tremula wood-based substrates. β-Glucan content in the fruiting bodies was highest with the MUS75 and P. tremula wood-based substrate. Based on these findings, the combination of P. tremula wood residues and the MUS192 strain is proposed to enhance the yield and β-glucan content of the fruiting bodies. A cold treatment of 5 °C is suggested to induce primordia formation and to increase fruiting probability. This is the first time that strains of G. lucidum originating from boreal forests have been compared and successfully cultivated simulating commercial indoor cultivation.

To understand the positional and temporal defense mechanisms of coniferous tree bark at the tissue and cellular levels, the phloem topochemistry and structural properties were examined after artificially induced bark defense reactions. Wounding and fungal inoculation with Endoconidiophora polonica of spruce bark were carried out, and phloem tissues were frequently collected to follow the temporal and spatial progress of chemical and structural responses. The changes in (+)-catechin, (−)-epicatechin, stilbene glucoside, and resin acid distribution, and accumulation patterns within the phloem, were mapped using time-of-flight secondary ion mass spectrometry (cryo-ToF-SIMS), alongside detailed structural (LM, TEM, SEM) and quantitative chemical microanalyses of the tissues. Our results show that axial phloem parenchyma cells of Norway spruce contain (+)-catechins, the amount of which locally increases in response to fungal inoculation. The preformed, constitutive distribution and accumulation patterns of (+)-catechins closely follow those of stilbene glucosides. Phloem phenolics are not translocated but form a layered defense barrier with oleoresin compounds in response to pathogen attack. Our results suggest that axial phloem parenchyma cells are the primary location for (+)-catechin storage and synthesis in Norway spruce phloem. Chemical mapping of bark defensive metabolites by cryo-ToF-SIMS, in addition to structural and chemical microanalyses of the defense reactions, can provide novel information on the local amplitudes and localizations of chemical and structural defense mechanisms and pathogen–host interactions of trees.