Colletotrichum rusci

The causative agent of this disease is the fungus Colletotrichum rusci, which is a significant pathogen belonging to the class of imperfect fungi. It is primarily known for causing anthracnose-type symptoms on specific ornamental hosts, leading to necrotic damage on the plant tissue.

The primary host for this fungus is Ruscus (butcher's broom). This plant is highly valued in the nursery industry and floriculture, making the management of this pathogen essential for maintaining economic value and plant aesthetics in commercial production.

The symptoms of infection include the appearance of small, irregular spots on the cladodes. These spots initially appear as water-soaked lesions, which later transition into brown or grey necrotic areas. As the disease progresses, small, dark fruiting bodies of the fungus emerge in the center of these spots, which can lead to complete tissue death.

Environmental conditions that favor the spread of Colletotrichum rusci include high humidity levels, poor air circulation, and warm temperatures, typically ranging from 20°C to 25°C. Spores are primarily disseminated by splashing water, irrigation, and through contaminated tools used during pruning or harvesting.

The economic impact of the disease is significant, as infected plants lose their visual appeal, rendering them unsellable. Effective management and protection strategies include:

• Implementing drip irrigation to avoid wet foliage.
• Improving greenhouse ventilation to reduce relative humidity.
• Removing and destroying infected plant debris immediately.
• Applying preventative fungicidal treatments, such as copper-based or systemic fungicides, during peak risk periods.