Stigmina leaf spot

Stigmina leaf spot is a plant disease caused by the fungal pathogen Stigmina sapii. This fungus primarily acts as a parasite, specifically infecting the foliage of woody plants. It belongs to the group of fungi that thrive in moist environments, causing significant damage to the photosynthetic capacity of the host plant.

The primary hosts of this pathogen are plants within the Sapium genus. While the disease may not always lead to immediate tree mortality, it significantly reduces the plant's vigor and ornamental value. In nursery settings, infections can spread rapidly, leading to substantial economic losses for growers.

Symptoms typically start as small, chlorotic spots on the leaves, which gradually develop into dark brown or necrotic lesions. As the fungus matures, it produces fruiting bodies that appear as tiny black pustules on the leaf surface. In severe cases, these spots can coalesce, leading to premature yellowing and dropping of the leaves.

The development and spread of Stigmina sapii are heavily influenced by environmental conditions, particularly high humidity, persistent leaf wetness, and moderate temperatures. The spores are disseminated through rain splashes, wind currents, and contaminated irrigation water, allowing the fungus to infect new leaves throughout the growing season.

Effective management requires a combination of sanitation and chemical control. Growers should prioritize the removal and disposal of all infected plant debris, which acts as a primary source of inoculum.

• Prune to improve airflow
• Remove fallen leaves
• Apply fungicides periodically