Abortiporus biennis

Abortiporus biennis is a pathogenic polypore fungus known for causing white rot in a variety of woody plants. As an agronomical threat, it primarily targets the root system and the base of the trunk, leading to severe decay of the inner wood and overall structural instability of the infected tree.

The host range for this pathogen is broad, encompassing many fruit trees such as apple and cherry, as well as various ornamental and forest species. The fungus typically enters the host through root wounds or compromised bark near the soil line, often where moisture levels are high, creating an ideal environment for colonization.

Symptoms are often not visible until the fungal infection is well-advanced. The most distinct sign is the emergence of bracket-like, porous fruit bodies near the base of the tree, which may appear leathery and brownish. Internally, the wood loses its integrity, becoming soft and fibrous, which significantly increases the risk of the tree collapsing during strong winds.

Environmental conditions that favor Abortiporus biennis include high soil humidity, poor drainage, and existing stress factors like drought or mechanical damage. The fungus persists in the soil through mycelial mats and rhizomorphs, allowing it to spread from tree to tree through underground root contacts.

Effective management requires a combination of cultural and chemical strategies. Proactive measures include removing dead wood, maintaining proper soil drainage, and preventing mechanical injury to the trunks and roots. If the infection is detected early, specialized fungicides may be applied to the surrounding soil, though severe cases often require the removal of the tree and the sterilization of the affected soil site.