Damping off diseases
Rhizoctonia spp.
Also Known As - Damping off and seed rotsWhat is Damping off diseases (Rhizoctonia spp., Fusarium spp., and Pythium spp.)?
Damping off is a soil-borne fungal disease that affects seeds and new seedlings in gardens. It is caused by pathogens such as Rhizoctonia spp., Fusarium spp., and Pythium spp. The disease is distributed worldwide and can impact a wide range of plants including vegetables (tomatoes, peppers, cucumbers, lettuce, etc.) and flowers (marigolds, petunias, snapdragons, etc.) It primarily targets seeds and new seedlings, causing the rotting of stem and root tissues. Symptoms include water-soaked, mushy seedlings, wilting leaves, and grayish-brown discoloration. Older, established plants are less affected by damping off.
How does Damping off diseases (Rhizoctonia spp., Fusarium spp., and Pythium spp.) occur?
These fungi can survive in the soil or plant debris and are introduced to the seedling tray through contaminated tools, potting media, or dirty hands. The pathogens spread from plant to plant through shared irrigation water or by growing through the potting media. Cool, wet conditions, overwatering, and slow plant growth contribute to increased susceptibility to damping off.
Symptoms
1 - Impacts on Plants
• It leads to seedling failure, stunted growth, and poor plant establishment. In addition, it can also cause root rot or crown rot in mature plants. • This disease reduces crop production, resulting in financial losses for farmers.
2 - Impact on Soil
• Damping off pathogens, including fungi and molds, can persist in the soil and plant debris. Infected soil can continue to pose a risk for future plantings and contribute to disease spread. • The presence of damping off pathogens can affect soil health and nutrient availability.
Solutions
1 - Prevention
• Use good-quality, sterile potting soil or sterilize your soil before planting. • Ensure proper sanitation of pots, trays, and gardening tools to prevent pathogen transfer. • Plant seeds thinly to avoid overcrowding and promote good air circulation. • Provide adequate drainage and avoid overwatering to reduce moisture levels. • Avoid planting seeds in cool, wet conditions and ensure optimal soil temperatures for germination. • Maintain proper light levels and ventilation to discourage fungal growth.
2 - Treatment
• Unfortunately, there is no cure for damping off once plants are infected. • Remove and discard affected seedlings and contaminated soil to prevent further spread. • Consider using biological fungicides, such as Mycostop, as a seed treatment to prevent disease. • Apply a systemic fungicide, like Organocide® Plant Doctor, as a soil drench or foliar spray to combat fungal problems. • Consult with local extension services or agricultural experts for specific treatment recommendations based on the causative pathogen.
