FUNGAL POPULATION AND COMMUNITY DEVELOPMENT IN CUT BEECH LOGS: II. ESTABLISHMENT VIA THE BURIED CUT SURFACE

Area of Science:

• Mycology
• Forest Ecology
• Wood Decay Fungi

Background:

• Fungal colonization of wood is crucial for decomposition.
• The entry point of fungi (basal vs. aerial) can influence colonization patterns and decay dynamics.
• Understanding these patterns is key to forest ecosystem processes.

Purpose of the Study:

• To investigate and compare fungal colonization patterns from the base versus the aerial surface of cut beech logs.
• To identify the primary fungal species involved in wood decay from different entry points.
• To analyze the role of somatic incompatibility in fungal community structure within decaying logs.

Main Methods:

• Cut beech logs were placed upright and partly buried in a mixed deciduous woodland.
• Fungal colonization from the basal and aerial surfaces was monitored over time.
• Isolates were identified, and somatic incompatibility reactions were assessed between different fungal species and isolates.

Main Results:

• Basal colonization by Xylaria hypoxylon and basidiomycetes (e.g., Armillaria bulbosa, Phanerochaete velutina) was rapid and distinct from aerial colonization.
• Xylaria hypoxylon frequently formed discrete decay columns, showing frequent somatic incompatibility.
• Armillaria bulbosa exhibited a lack of somatic incompatibility, suggesting a single widespread mycelial type.

Conclusions:

• Fungal colonization patterns are highly dependent on the wood surface of entry.
• Vertical penetration from the log base is faster than from the aerial surface, with X. hypoxylon as a key pioneer species.
• Somatic incompatibility plays a significant role in structuring fungal communities within decaying wood, with variations observed between species.