The Specific and Total CO2 Emission Activity of Wood-Decaying Fungi and Their Response to Increases in Temperature.

The CO2 emission activity of xylotrophic fungi responding to an increase in temperature in the range of 10-30 °C with pure dikaryotic cultures of Fomes fomentarius s. str., F. inzengae, Fomitopsis betulina, F. pinicola, and Phellinus igniarius was analyzed. Emission activity was assessed by the difference in CO2 concentration in 0.5 L exposure chambers with Petri dishes with mycelium growing on agar at the beginning of exposure and an hour later using a Gasmet DX-4030 FTIR spectrometer (Gasmet Technologies Oy, Finland), error measurements ±50 ppm. Specific (µg CO2/cm2/h) and total (µg CO2/h) emission activity and its relationship with temperature and size (area) of the mycelium were assessed. It is shown that in the range of 10-30 °C, the specific and total CO2 emission activity of the mycelium is closely and positively related to temperature. Specific emission, which is an indicator of the respiratory activity of the mycelium, does not depend on its size; its only driver is temperature, the relationship with which is linear: an increase in temperature by 10 °C causes an increase in the specific emission activity of the mycelium by 1.7 times. The total CO2 emission activity, which is an indicator of the total amount of CO2 emitted, is directly proportional to the specific emission activity and the size of the mycelium. In the range of 10-30 °C, an increase in temperature causes an almost equal increase in both the specific emission activity of the mycelium (Q10 1.7) and its growth (Q10 1.5) and causes an exponential increase in the total emission of CO2. This must be taken into account when predicting CO2 emissions from woody debris under climate change, as it could potentially contribute to accelerating climate change.

Eco-Physiological Adaptations of the Xylotrophic Basidiomycetes Fungi to CO2 and O2 Mode in the Woody Habitat.

The aim of this research is to study of eco-physiological adaptations of xylotrophic fungi (Basidiomycota, Agaricomycetes) to hypoxia, anoxia and hypercapnia as the main environmental factors that determine the activity of fungi in woody habitat. The study was carried out on seven species of polypore fungi widespread in the preforest-steppe pine-birch forests of the Central Urals, including both white (D. tricolor, D. septentrionalis, F. fomentarius, H. rutilans, T. biforme) and brown (F. betulina, F. pinicola) rot. Their CO2 and O2 gas exchange were analyzed in natural samples of woody substrates (Betula pendula, Pinus sylvestris) and basidiocarps by the chamber method using a CO2/O2 gas analyzer. It was shown that the intensity of O2 gas exchange is positively related to the oxygen concentration but is not very sensitive to a decrease in its content in the woody habitat. Xylotrophic fungi are able to completely exhaust the O2 in the habitat, and this process is linear, indicating that they do not have threshold values for oxygen content. Oxygen consumption is accompanied by an adequate linear increase in CO2 concentration up to 18-19%. At a concentration of 5-10%, carbon dioxide does not affect the gas exchange of xylotrophic fungi and can even enhance it, but at 20% it significantly reduces its intensity. Xylotrophic fungi are resistant to high CO2 concentrations and remain viable at 100% CO2 concentration and are capable of growth under these conditions. In an oxygen-free habitat, anaerobic CO2 emissions are recorded; when O2 appears, its consumption is restored to the level preceding anoxia. Xylotrophic fungi are the specialized group of saprotrophic microaerophilic and capnophilic facultative anaerobes adapted to develop at low oxygen and high carbon dioxide concentration, anoxia.

Notes on Medicinal Polypore Species from the Genus Daedaleopsis (Agaricomycetes), Distributed in the Asian Part of Russia.

We present a study on the medicinal value, taxonomy, and ecology of the polypore mushrooms Daedaleopsis confragosa and D. tricolor isolated from the Asian part of Russia (the Urals, Siberia, and the Far East). The phylogenetic analysis of recombinant DNA internal transcribed spacer sequences data has shown that D. confragosa and D. tricolor do not differ taxonomically and should be considered as one species. However, because D. confragosa and D. tricolor differ significantly in their ecological characteristics, they may be considered as two morpho-ecological varieties: D. confragosa var. confragosa and D. confragosa var. tricolor (both nomen provisiorum).

Genetic Variability of the Medicinal Tinder Bracket Polypore, Fomes fomentarius (Agaricomycetes), from the Asian Part of Russia.

We analyzed intraspecies genetic variability of the medicinal tinder bracket polypore, Fomes fomentarius, from the Asian part of Russia, including the Ural, Altai, Western Sayan, and Baikal regions. We used nuclear ribosomal DNA internal transcribed spacer (ITS) sequence data as a standard marker for fungal DNA barcoding. In the Asian part of Russia, lineage A occurs as sublineage A2, which differs from sublineage A1 by a single nucleotide insertion at ITS2.3. Sublineage A2 is distributed up to Lake Baikal in the Ural, Altai, and Western Sayan regions. It can be characterized as a Eurasian sublineage of F. fomentarius. Lineage B is also represented by 2 sublineages (B1 and B2), which differ from each other by nucleotide sequences at ITS2.1. Sublineage B1 is represented by a small group of isolates from Asia (Iran, China, Nepal, South Korea), whereas sublineage B2 mainly includes isolates from Europe (Great Britain, Italy, Latvia, Slovakia, Slovenia) and 2 separate samples from Asia (Iran, China); these locales compose the distribution area of F. fomentarius. In the Asian part of Russia, lineage B is represented by sublineage B2 found in the Southern Urals (at the border between Europe and Asia), which is the only area where sublineages A2 and B2 are present. These sublineages are characterized by different substrate spectra: sublineage A2 is predominantly associated with Betula spp. and rarely with Alnus and Larix trees, whereas sublineage B2 does not have a pronounced substrate preference and is found in basidiomes collected from Acer, Duschekia, Prunus, and Salix trees, but not Betula trees. In general, the spectrum of substrates for F. fomentarius lineages A and B in the Asian part of Russia corresponds to that in other parts of this polypore's distribution area. Data are needed on genetic intraspecies variability (polymorphism) in relation to pharmacological properties for further biotechnological cultivation and use of the medicinal fungus F. fomentarius.