What is damping-off, which stage of plant growth does it affect, and how can it be prevented in seed starting trays?

What is damping-off, which stage of plant growth does it affect, and how can it be prevented in seed starting trays?

• A. A pest insect that feeds on seeds; use insecticides
• B. A fungal disease that causes seedling collapse at the seedling stage; prevent with sterile starting mix, proper spacing, adequate air circulation, and controlled moisture
• C. A nutrient deficiency causing leaf curling; apply fertilizer
• D. A drought stress causing seed dormancy; water less

Answer: (B)

Damping-off is a fungal disease that attacks very young seedlings, usually causing the stem near the soil line to soften, collapse, and the plant to fall over or fail to stand. It shows up at the seedling stage, right after germination, when plants are most vulnerable in crowded, moist conditions. Prevention in seed starting trays centers on minimizing the conditions that favor these pathogens. Start with sterile starting mix and clean trays and tools to reduce the amount of inoculum introduced. Give seedlings enough space and ensure good air movement so humidity around the tops of the pots isn’t kept high and stagnant. Manage moisture carefully—water the trays so the mix stays evenly moist but never waterlogged, and avoid keeping soil surface constantly wet by allowing it to dry slightly between waterings and ensuring the tray drains well. Maintaining moderate temperatures and good drainage, along with sanitizing equipment, further lowers risk. If you notice a seedling collapsing, remove the affected plants promptly to reduce spread.

Damping-off is a fungal disease that attacks very young seedlings, usually causing the stem near the soil line to soften, collapse, and the plant to fall over or fail to stand. It shows up at the seedling stage, right after germination, when plants are most vulnerable in crowded, moist conditions.

Prevention in seed starting trays centers on minimizing the conditions that favor these pathogens. Start with sterile starting mix and clean trays and tools to reduce the amount of inoculum introduced. Give seedlings enough space and ensure good air movement so humidity around the tops of the pots isn’t kept high and stagnant. Manage moisture carefully—water the trays so the mix stays evenly moist but never waterlogged, and avoid keeping soil surface constantly wet by allowing it to dry slightly between waterings and ensuring the tray drains well. Maintaining moderate temperatures and good drainage, along with sanitizing equipment, further lowers risk. If you notice a seedling collapsing, remove the affected plants promptly to reduce spread.