Green House Management Practice Test

Damping-off happens when the young seedlings are attacked at the soil line by pathogens that live in the soil. The most common culprits are fungi that colonize the soil and infect the tender stem and seedling roots, especially under wet, poorly drained, and crowded conditions. These soilborne fungal pathogens (and related water molds) thrive when humidity and dampness are high, allowing them to girdle or rot the stem at the soil surface and cause the seedling to collapse. That broad group explains why damping-off is so prevalent in nurseries and seedbeds with wet media. Bacteria, nematodes, and viruses can cause other seedling problems, but they don’t typically produce the classic damping-off pattern of rapid collapse at the soil line driven by soilborne fungal pathogens. To reduce damping-off, manage moisture, improve drainage and air movement, use clean, sterile media, avoid overcrowding, and sanitize tools and benches.