Cavity spot

Pythium sulcatum

Causal Agent:

Pythium sulcatum is a species of water mold (oomycete) that can cause damping-off and root rot in various plants, including vegetables, ornamentals, and crops.

Symptoms:

  1. Damping-Off:

    • Seedlings may exhibit damping-off symptoms, leading to the rotting of seeds before or after germination.

  2. Root Rot:

    • Infected plants may show symptoms of root rot, including discoloration, decay, and a general lack of healthy root development.

  3. Stunted Growth:

    • Plants infected with Pythium sulcatum may exhibit stunted growth due to impaired root function.

  4. Wilting:

    • Wilting may occur as a result of damaged or non-functional root systems.

Conditions Favoring Disease:

  1. Waterlogged Soil:

    • Optimal Growth Conditions: Pythium species thrive in waterlogged or overly moist soil conditions.

  2. High Soil Moisture:

    • Excessive irrigation or poor drainage can contribute to the development of Pythium diseases.

Management:

  1. Proper Drainage:

    • Ensure proper drainage to prevent waterlogged soil conditions.

  2. Avoid Overwatering:

    • Practice careful irrigation to avoid overwatering and waterlogging.

  3. Sanitation:

    • Remove and destroy infected plant material to reduce the source of inoculum.

  4. Fungicide Treatment:

    • In some cases, the application of fungicides may be considered, especially as preventive measures in areas prone to Pythium issues.

Note: Pythium sulcatum is one of many Pythium species that can cause root rot and damping-off diseases in plants. Prevention and management strategies often focus on improving soil drainage, avoiding overwatering, and employing sanitation practices. Additionally, using disease-resistant plant varieties and treated seeds can be effective preventive measures.