Cylindrocladiella elegans

Cylindrocladiella elegans is a soil-borne fungal pathogen responsible for significant root and basal stem rot diseases in a variety of horticultural and nursery crops. This fungus is known for its ability to persist in soil for extended periods, utilizing resilient structures that survive various environmental stresses, making it a persistent challenge for plant health management in greenhouse environments.

The pathogen primarily affects the root systems and crowns of young plants, including seedlings and cuttings. Common hosts include ornamental woody species, such as Eucalyptus and Protea, as well as various greenhouse crops. Infection often occurs at the root-stem junction, leading to systemic damage that compromises the entire vascular system of the host plant.

Clinical signs of infestation manifest as stunted growth, leaf chlorosis, and sudden wilting. A detailed inspection of the root system often reveals dark, necrotic tissue and a significant reduction in fine root density. As the rot progresses, the base of the stem may become soft and discolored, eventually causing the plant to collapse due to total system failure.

Disease development is heavily favored by warm, humid conditions and poorly aerated growth media. The pathogen spreads effectively through contaminated irrigation water, infected soil particles, and handling by human activity, including contaminated tools and pots. Once established in a nursery, the disease can spread rapidly through closely spaced plant batches.

Effective management requires a multi-faceted approach centered on strict sanitation. Essential practices include:

• Utilizing pathogen-free, sterilized potting media for all propagation.
• Implementing rigorous sanitation protocols for tools, benches, and irrigation systems.
• Ensuring proper drainage and ventilation to maintain root zone health.
• Applying preventive fungicide treatments based on biological or chemical standards when conditions for infection are high.