Phloeospora leaf spot

Phloeospora leaf spot is a dangerous fungal disease of plants caused by imperfect fungi of the genus Phloeospora. The disease belongs to the leaf spot group and is characterized by damage mainly to the leaf apparatus, which leads to a disruption of photosynthesis processes and premature leaf fall.

The main crops susceptible to this disease include pome and stone fruit trees, as well as some ornamental shrubs. The fungus causes the greatest damage in nurseries and young orchards, where the weakening of the foliage leads to reduced winter hardiness and slowed overall growth of the saplings.

Symptoms of the infection manifest as small, often angular spots, which can be brown, tan, or grayish in color. Over time, the tissue in the spots necrotizes, may crack, and fall out. In high humidity, conidial sporulation pads of the pathogen form on the underside of the leaves.

The development of the disease is closely linked to weather conditions. High air humidity, frequent rainfall, and moderate temperatures provide an ideal environment for the spread of fungal spores. The infection most often persists in diseased fallen leaves, where the fungus overwinters in the form of mycelium or conidia, beginning its active cycle in spring when favorable weather conditions occur.

Protection measures include a complex of agrotechnical and chemical practices. It is crucial to timely remove and destroy fallen foliage, where the primary inoculum accumulates. During the growing season, it is recommended to carry out preventive and curative treatments with fungicides based on copper or broad-spectrum systemic preparations.

• Adherence to crop rotation and spatial isolation.
• Sanitary pruning and destruction of plant debris.
• Regular fungicide applications during the growing season.
• Cultivation of resistant varieties and hybrids.