Botryosphaeria dothidea

Causal Agent: Botryosphaeria dothidea is a fungal pathogen that causes canker diseases in a wide range of woody plants, including trees, shrubs, and fruit crops.

Symptoms:

1. Cankers:

   • The fungus induces the formation of cankers on branches, stems, and trunks of infected plants.
   • Cankers often appear sunken, discolored, and may have a dark, necrotic center.

2. Dieback:

   • Infected branches may experience dieback, leading to a reduction in the plant's overall vigor.

3. Fruit Rot (in fruit crops):

   • In fruit crops, such as apples and pears, Botryosphaeria dothidea can cause fruit rot, resulting in the decay of fruits.

4. Foliage Symptoms:

   • Wilting, yellowing, or browning of foliage in the affected areas.

Identification:

1. Cankers:

   • Identification is based on the presence of sunken, discolored cankers on stems and branches.

2. Fruiting Bodies:

   • The fungus may produce small, dark, pimple-like structures (pycnidia) on the surface of infected bark.

Conditions Favoring Disease:

1. Wounds and Stress:

   • Infection often occurs through wounds or stressed plant tissues.

2. Warm and Humid Conditions:

   • Optimal Growth Conditions: The fungus thrives in warm and humid environments.

Management:

1. Pruning:

   • Prune and remove infected branches, promoting air circulation and reducing disease spread.

2. Sanitation:

   • Remove and destroy infected plant material, including cankered branches, to minimize inoculum.

3. Fungicides:

   • Application of fungicides may be considered for managing the disease, especially in high-risk situations.

4. Stress Reduction:

   • Minimize stress factors, such as drought or excessive pruning, to enhance plant vigor.

Note: Botryosphaeria dothidea is known to be a significant pathogen causing canker diseases in various plant species. Effective disease management involves a combination of cultural practices, pruning, and, in some cases, chemical control.