Broomella acuta

Broomella acuta is a pathogenic fungus belonging to the class Ascomycetes. In agricultural practice, this microorganism is identified as the causative agent of specific fungal infections in plant tissues, which manifest primarily as necrotic spots. The pathogen leads a parasitic lifestyle, utilizing plant tissues as a substrate for the development of its fruiting bodies, known as pseudothecia.

The primary hosts of this fungus are various species of trees and shrubs, as well as certain herbaceous crops. Broomella acuta is most frequently found on fallen leaves and weakened shoots, where the fungus completes its sexual reproductive cycle. Although the pathogen is often considered a saprotroph, under high humidity conditions, it shifts to actively attacking living tissues, causing premature wilting and necrosis of stem or leaf segments.

The symptoms of the disease appear as small, well-defined, irregularly shaped spots that darken and crack over time. At the site of infection, the plant epidermis breaks down, facilitating the entry of secondary infections. A characteristic sign of the disease is the appearance of tiny black dots—the ascostromata—on the surface of the affected areas, which serve as the fungus's spore-bearing organs.

The development and spread of the infection are favored by periods of prolonged rain, high air humidity, and moderate temperatures. The fungus's spores, known as ascospores, are actively dispersed by air currents or rain splashes, infecting healthy parts of the plant. The spring-summer period is considered the most favorable time for disease outbreaks, as plants are in their active growth stage and may be stressed by environmental factors.

Strategies for controlling the pathogen involve an integrated agronomic approach. Firstly, it is essential to perform sanitary pruning and timely disposal of infected plant debris, as this is where the fungus overwinters. To prevent widespread outbreaks, the application of broad-spectrum fungicides during the growing season is recommended. Effective prevention also includes ensuring proper airflow and canopy management to reduce humidity levels in the root and foliage zones.