Sooty mold (black mold)

Disease name: sooty mold (black mold)

The scientific name: pezizomycotina

Type of disease: fungal

Disease family: Pezizomycetes

(Image showing the shape of a mushroom Pezizomycetes)

• The causes of disease:

considered as pezizomycotina Non-parasitic fungi, they derive their food from the secretions of insects and plants. The most common food for these fungi is honeydew, which is a liquid secretion released from the anus of some types of insects and some types of leafhoppers.

• Symptoms of the disease:

Dark fungal deposits appear on the leaves, coloring the leaf surface in different shades of black. As the infection progresses, the fungi cover all the leaves. Because they are considered non-pathogenic parasites, they do not show any disease symptoms on the tree as they do not colonize in plant tissues.

(mushroom pezizomycotina covers infected lemon plant leaves)

• Disease development cycle:

These fungi reproduce through ascospores and conidia. Some insects, such as ants, aphids, and whiteflies, tend to protect the fungal colonies so that they can attack the phloem fluid of the plant.

• Conditions suitable for the spread of the disease:

Mold grows in humid conditions resulting from irrigation water or rainwater, and (15-20) degrees Celsius is considered the optimal temperature for mushroom growth.

(Sooty mold disease develops and spreads greatly)

• Losses resulting from the spread of the disease:

This fungus blocks sunlight from the leaves, which prevents the leaves from carrying out the photosynthesis process, by covering the leaves, and also prevents them from breathing and exchanging gases with the atmosphere, which may lead to the death of the plant.

• Control:

1. Isolate the infected plant to avoid its spread in the field.
2. Use organic neem oil to repel insects that protect fungal colonies and even limit the growth of fungi.
3. Spray insecticidal soap on infected plants and rinse with water to remove the mold.
4. Use pesticides that contain organophosphates, such as malathion, to prevent insects from feeding on the plant.

• preventive measures:

1. Good fertilization of the plant to combat parasites that attack the plant.
2. Irrigate trees in moderation to avoid providing a suitable environment for fungus growth.
3. Ensure there is a distance between trees in the field to avoid transmission of the disease between nearby trees.
4. Sterilizing agricultural tools to ensure that the disease is not transmitted.

• Sources:
• https://plantix.net/en/library/plant-diseases/100192/sooty-mold/
• https://ipm.ucanr.edu/PMG/PESTNOTES/pn74108.html