Seedling Damping-Off in Plumeria: Identification, Prevention, and Control

Damping-off is a widespread and destructive disease complex that kills plumeria seedlings before or shortly after emergence. Prompt recognition and preventative cultural practices are vital to minimize losses and promote healthy seedling establishment.

Understanding Damping-Off

• Caused by multiple soilborne fungi including Pythium, Phytophthora, Fusarium, and Rhizoctonia.
• Infects seeds and seedlings at or just below the soil surface, attacking roots and stem bases.

Symptoms

• Failure of seeds to germinate or produce weak seedlings.
• Seedlings collapse suddenly at soil level or below, often appearing water-soaked.
• Seedlings may show yellowing or wilting before falling over.
• Soil surface may be covered with fungal growth or slimy patches.

Favoring Conditions

• Excess moisture and poor drainage are primary contributors.
• High humidity and stagnant air increase fungal activity.
• Overcrowding creates favorable microclimates for infection.

Prevention

• Use sterile growing media and containers.
• Avoid overwatering; maintain moist but well-drained conditions.
• Ensure good airflow and avoid dense seedling arrangements.
• Surface sterilize seeds before planting.
• Disinfect tools and surfaces regularly.

Control Measures

• Remove infected seedlings immediately.
• Apply fungicides recommended for damping-off prevention and treatment.
• Adjust watering and environmental conditions to discourage pathogen survival.