Colletotrichum sydowii

Colletotrichum sydowii is a fungal pathogen belonging to the Colletotrichum genus, primarily recognized as a causative agent of anthracnose. This fungus is a significant threat in agricultural production, capable of infecting a wide range of host plants and causing substantial damage to vegetative and reproductive tissues.

The host range of Colletotrichum sydowii includes various berry crops, such as strawberries, as well as several ornamental plants and vegetables. The fungus typically attacks leaves, petioles, stems, and fruits, leading to localized necrosis that can eventually result in the total collapse of infected organs if conditions remain favorable for the pathogen.

Symptoms of the disease are characterized by the appearance of sunken, dark-colored lesions on the affected plant parts. These lesions often contain acervuli, which are tiny, cushion-shaped fruiting bodies that emerge through the epidermis. Under high humidity, these structures produce masses of spores, often appearing as gelatinous pinkish or whitish droplets that spread via rain splash or irrigation water.

The development and spread of Colletotrichum sydowii are heavily influenced by environmental conditions, particularly high relative humidity and temperatures between 20°C and 25°C. The pathogen persists in the environment by surviving on decaying plant debris, in the soil, or on alternative weed hosts, acting as a reservoir for annual re-infection.

Managing this disease requires an integrated plant protection strategy. Essential practices include the implementation of crop rotation, the use of disease-free propagation material, and the removal of infected plants to reduce inoculum pressure. Furthermore, the targeted application of systemic and contact fungicides during periods of high humidity is critical for maintaining crop health and productivity.