Brown Spotting of Pear

Brown Spotting of Pear

Stemphylium vesicarium

Stemphylium vesicarium is a parasitic fungus that affects plants and causes brown spots on the pear tree. It is an insidious fungus that is capable of ruining entire crops. The fungus is capable of causing lesions on the epidermis of pear trees since during its vegetative activity it processes toxic substances for the plant. In the areas that are then necrotized by toxins, a process of rotting develops that extends to the plant. The fungus is easily localized in humid areas, where there are loamy or clayey soils and in the absence of proper ventilation of the plants. The fungus is able to resist from one year to the next both on the leaves and on the fruits fallen to the ground, resuming its vegetative and pathogenetic activity in the spring. The fungus develops with a temperature between 22 and 26 degrees.


Brown spot on the pear tree

The main symptoms of this particular type can be highlighted throughout the period from flowering to harvest. The disease manifests itself with necrotic spots on the leaves, on the fruits, on the twigs. On the green parts of the plant you may begin to notice pinpoint spots which, proceeding with the infection, are capable of causing necrotization of all tissues. On the fruits, the lesions can be more evident in the parts most exposed to light. On the fruits initially brown spots are formed with a size of a few millimeters which then enlarge while always maintaining a circular shape. If the infection is not adequately counteracted, it could extend to the pulp starting a process that will lead to the rot of the fruit.


Development of the brown spot of the pear tree

The development of the pathology is strongly influenced by the environmental conditions and the general conditions of the plants that are affected by this pathology. For example, a high incidence of the disease was found on plants that were not very vigorous or with chlorosis due to a lack of nutrients or water stagnation. Soils that are too compact and lacking in aeration and oxygenation can be one of the causes of the development of the disease. The lack of tillage and excessive irrigation can represent factors that influence the proliferation of the fungus, creating an environment suitable for its survival. The most sensitive parts of the plant are those that are in the growth phase. The disease develops mainly in the presence of wet parts of the plant which, if it persists for a long time, is an ideal environment for the development of the pathology.


Brown Pear Spotting: Prevention and treatment of this pathology

For the care of plants affected by brown pear spots, specific fungicides could be used, or products based on copper salts or ethyl aluminum phosphite could be used. In addition to proceeding with products for the treatment of the disease, preventive interventions should be implemented that do not allow the adequate development of the fungus. First of all, watering should be limited, above all you should absolutely avoid wetting the hair. Fruits affected by the disease and fallen to the ground should be destroyed, the leaves should be buried, but only after being treated with urea to facilitate the degradation process. The fertilization phase is delicate and should be correctly balanced in the elements introduced.


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