Tomentella lateritia

Tomentella lateritia is a basidiomycetous fungus belonging to the Thelephoraceae family. It is recognized as a soil-borne pathogen or saprotroph that can influence plant health, particularly in nursery settings, forestry, and areas with high soil moisture. The name originates from its distinct rusty, brick-red (lateritious) fungal mats that form on infested substrates.

This fungus primarily affects the root systems and the root collars of various woody plants and shrubs. By colonizing these areas, the mycelium can disrupt the water and nutrient uptake of the host plant. While it often acts as a secondary invader, under favorable conditions, it can become a primary stressor leading to the decline of seedlings and young plants.

The characteristic symptoms of infection involve the appearance of a visible, brick-red, crust-like mycelial layer on the root neck or directly on the exposed roots near the soil line. Plants showing signs of infestation often exhibit reduced vigor, yellowing leaves, stunting, and in severe cases, progressive dieback as the root integrity is compromised.

The spread of Tomentella lateritia is highly dependent on environmental factors, specifically high humidity and waterlogged soil conditions. Poor aeration, shading, and the accumulation of decaying woody debris serve as ideal substrates for the fungus to thrive and produce spores. These conditions facilitate its transmission throughout a planting area or nursery bed.

Control and prevention are centered on good cultural practices, such as ensuring proper soil drainage and optimizing spacing between plants to improve airflow. Infected plant materials should be promptly removed and destroyed to prevent spore dispersal. When necessary, chemical control using targeted soil fungicides can help manage outbreaks in high-value ornamental or forest nurseries.

• High soil moisture levels.
• Poor air circulation.
• Accumulation of decaying organic matter.
• Inadequate root zone aeration.