Cylindrocladium root rot

The fungus produces microsclerotia, which serve as long-term survival structures. These structures allow the pathogen to withstand adverse environmental conditions and initiate new infections once host plants are present.

This pathogen primarily targets soybeans, causing severe root and hypocotyl rot. It is a major threat in regions with warm, wet growing seasons where the pathogen can spread rapidly through the soil profile.

Beyond soybeans, C. parasiticum has a wide host range, attacking numerous nursery crops and woody ornamental species. The damage results in stunted plant growth, reduced stand density, and significant yield losses.

Symptoms typically manifest as yellowing and wilting of the leaves, starting from the lower canopy. If the plants are pulled from the soil, the roots will show distinct reddish-brown to black necrotic lesions.

Under high humidity, a characteristic white to light-grey fungal sporulation layer may develop on the stems near the soil line. This indicates active spore production and potential spread to neighboring plants.

Management of the disease centers on preventative measures, primarily crop rotation with non-host species to reduce the level of inoculum in the field. Improving soil drainage is also critical to minimize the moisture levels required for fungal proliferation.

• Utilizing resistant soybean varieties.
• Sanitizing farm equipment to prevent soil movement.
• Applying systemic fungicides as seed treatments.
• Implementing deep tillage to incorporate infested debris.