Fairy-ring leaf spot
Cladosporium echinulatum
Also Known As - Leaf spot Fairy-ringWhat is Fairy Ring Spot (Cladosporium echinulatum)?
Fairy Ring Spot is a fungal disease affecting carnations (Dianthus caryophyllus) caused by Cladosporium echinulatum. Symptoms include circular to oval spots with purple margins developing on flower stalks, diminishing their aesthetic appeal. The disease is found in various regions, including Africa, India, Japan, Europe, Brazil, and Venezuela. Cladosporium echinulatum can also infect other plants like Sweet Williams, Lychnis, Saponaria, and other members of the Caryophyllaceae family.
How does Fairy Ring Spot (Cladosporium echinulatum) occur?
Cladosporium echinulatum harms plants in its conidial stage. The fungus has septate mycelium, appearing as subhyaline to olivaceous brown. Conidiophores produce conidia, which are yellowish-brown and echinulate. Abundant spores form on leaf undersides during the rainy season, spreading through wind, cultural practices, and more. It begins in greenhouse corners, thriving in cool and humid conditions, quickly causing substantial damage to plants.
Symptoms
1 - Impact on Plants
The fungus causes Fairy Ring Spot disease, forming circular to oval spots on plants. These spots diminish the plants' appearance and can cause significant damage if not treated.
2 - Soil Health
1. Cladosporium echinulatum competes with plants for nutrients, potentially reducing nutrient availability for plant growth and development. 2. The presence of pathogens can impact the composition and diversity of soil microbial communities, which play a vital role in nutrient cycling and overall soil health.
3 - Impacts on Environment
1. Its presence can disrupt ecosystem balance by impacting plant communities and potentially altering species composition. 2. The airborne spores of the pathogen contribute to the spread of the fungus, potentially affecting neighboring plants and ecosystems.
Solutions
1 - Cultural Practices
1. Regulate Greenhouse Condensation: Control condensation by improving ventilation and heating practices to reduce moisture buildup. 2. Utilize Ventilation and Heating: Ensure proper airflow and temperature to create unfavorable conditions for Cladosporium growth. 3. Morning Irrigation: Water plants in the morning to allow foliage to dry quickly and minimize moisture for fungal development. 4. Remove Senescing and Dead Tissue: Regularly eliminate senescent and dead plant material to prevent Cladosporium sporulation.
2 - Bioagent
Bacillus amyloliquefaciens is a beneficial bioagent that can be used as a natural control method against carnation fairy ring spot.
3 - Application of Fungicides
Several fungicides can be used to manage Fairy Ring Spot in carnations. Examples include Mancozeb tebuconazole, propineb, captafol, zineb, tricarbamix, chlorothalonil, and triforine. These fungicides target the pathogen directly, reducing its growth and suppressing disease symptoms.
