Interactions between Fine Wood Decomposition  and Flammability

Abstract Saprotrophic cord-forming basidiomycetes, with their mycelial networks at the soil/litter interface on the forest floor, play a major role in wood decomposition and nutrient cycling/relocation. Many studies have investigated foraging behaviour of their mycelium, but there is little information on their intelligence. Here, we investigate the effects of relative size of inoculum wood and new wood resource (bait) on the decision of a mycelium to remain in, or migrate from, inoculum to bait using Phanerochaete velutina as a model. Experiments allowed mycelium to grow from an inoculum across the surface of a soil microcosm where it encountered a new wood bait. After colonisation of the bait, the original inoculum was moved to a tray of fresh soil to determine whether the fungus was still able to grow out. This also allowed us to test the mycelium’s memory of growth direction. When inocula were transferred to new soil, there was regrowth from 67% of the inocula, and a threshold bait size acted as a cue for the mycelium’s decision to migrate for a final time, rather than a threshold of relative size of inoculum: bait. There was greater regrowth from the side that originally faced the new bait, implying memory of growth direction.

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Decomposition of Organic Chemical Components in Wood by Tropical Xylaria Species

Journal of Fungi ◽

10.3390/jof6040186 ◽

2020 ◽

Vol 6 (4) ◽

pp. 186

Author(s):

Takashi Osono

Keyword(s):

Mass Loss ◽

Leaf Litter ◽

Tree Species ◽

Chemical Components ◽

Organic Chemical ◽

Klason Lignin ◽

Wood Decomposition ◽

Recalcitrant Compounds ◽

Initial Content

The ability of Xylaria species obtained from tropical wood and leaf litter to cause a mass loss of lignin and carbohydrates in wood was examined in vitro with pure culture decomposition tests. The mass loss of wood of four tree species caused by nine Xylaria isolates ranged from 4.5% to 28.4% of the original wood mass. These Xylaria isolates have a potential ability to decompose lignin and other recalcitrant compounds, collectively registered as acid unhydrolyzable residues or Klason lignin in wood. The origin of isolates (i.e., isolates from wood versus leaf litter) did not affect the mass loss of acid unhydrolyzable residue in wood. The Xylaria isolates tested generally caused a selective decomposition of polymer carbohydrates in wood in preference to acid unhydrolyzable residue. The mass loss of acid unhydrolyzable residue caused by Xylaria isolates varied with the tree species of the wood and was negatively related to the initial content of acid unhydrolyzable residue in wood, implying the limiting effect of lignin and recalcitrant compounds on wood decomposition by Xylaria isolates.

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Bedding of Wetland Soil: Effects of Bed Height and Termite Activity on Wood Decomposition

Soil Science Society of America Journal ◽

10.2136/sssaj2018.12.0492 ◽

2019 ◽

Vol 83 (S1) ◽

Cited By ~ 3

Author(s):

Martin F. Jurgensen ◽

Chris A. Miller ◽

Carl T. Trettin ◽

Deborah S. Page‐Dumroese

Keyword(s):

Wetland Soil ◽

Wood Decomposition ◽

Bed Height ◽

Soil Effects

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Exploratory Sampling of Spalting Fungi in the Southern Peruvian Amazon Forest

Challenges ◽

10.3390/challe11020032 ◽

2020 ◽

Vol 11 (2) ◽

pp. 32

Author(s):

Sarath M. Vega Gutierrez ◽

Javier F. Illescas Guevara ◽

Claudia C. Andersen ◽

Jose Koechlin von Stein ◽

Seri C. Robinson

Keyword(s):

Tree Species ◽

Economic Value ◽

Economic Importance ◽

Edible Mushrooms ◽

Amazon Forest ◽

Peruvian Amazon ◽

Fruiting Bodies ◽

Wood Decomposition ◽

Decay Fungi ◽

Madre De Dios

Most of the research related to Peruvian Amazon fungi is focused on edible mushrooms and pathogens. Other important fungi, such as the spalting type (decay fungi that pigment wood internally), are not broadly studied, as most of them do not produce fruiting bodies and can be difficult to locate. Spalting fungi, however, are of broad economic importance due to their ability to produce pigments that enhance wood aesthetics, resulting in an increased economic value. In order to begin understanding the diversity of spalting fungi within certain regions of the Amazon, a sampling of downed trees and branches (through the opening of the xylem to identify potential pigmenting and zone line producing fungi) was done in the district of Las Piedras, Madre de Dios, Peru. Fungi suspected of causing internal pigment and zone lines were collected, cultured, isolated, and sequenced. The species found belonged to the orders Helotiales, Xylariales, Hypocreales, Russulales, Polyporales, Botryosphaeriales and two specimens of the class Leotiomycetes. The fungi collected produced pigments or zone lines in wild conditions and all of them were capable of wood decomposition. Interestingly, these are the same orders and genera as North American spalting fungi, which may indicate a correlation within species that pigment wood. The results obtained start a specific database of spalted fungi in the Amazon and, with it, help support an effort to increase the forest value of ecosystems primarily used for a few high-valued tree species.

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