According to the database Species fungorum , Taphrina insititiae is not recognized as an independent species, this name is considered a synonym for Taphrina pruni - plum Tafrina [1] . This point of view was expressed repeatedly over the course of the 20th century, for example, in 1949 by A. Mix , in 2000 by Herum [Halvor B. Gjaerum] [2] . At the same time, many researchers pointed to morphological differences - in tafrina, torns are shorter and wider asks than in plum; tafrina was also called a causative agent of witch brooms, and plum was called “ blown fruit ” [3] [4] .
Tafrina of thorn causes the growth of shoots and the formation of “witch brooms,” the leaves on such shoots become wavy, “corrugated” [2] [5] . “Witches brooms” have a densely bushy appearance, branches are deformed, the affected shoots are dense, thin, poorly developed [6] .
The intercellular mycelium hibernates in the tissues of branches.
The marsupial layer (" hymenia ") is waxy, gray or whitish, develops more often on the underside of leaves.
Ascores are eight-spore, club-shaped or cylindrical with a rounded, less often sharp apex, measuring 25-30 × 8-10 microns. Basal cells ( see Tafrin's article ) 6-8 × 7-10 microns, short, usually with a pointed, less often with a flat base, wedge between the cells of the epidermis of the plant.
Ascospores are spherical or ellipsoidal, 3.5–4 μm in size, sometimes budged in the asci [2] [5] .
The typical host is Stubborn ( Prunus insititia ), which also infects home plums ( Prunus domestica ). The species was first described in Denmark , and its distribution is also indicated for the Scandinavian Peninsula , Central and Eastern Europe ( Poland , Ukraine ), Transcaucasia , Asia Minor, and Japan [2] .
When “witch brooms” appear on the drain, the affected branches are cut and destroyed, the wounds are covered. For spraying, 1% copper sulfate or 2% Bordeaux fluid is used , treatment with these drugs is carried out in the spring, a few days before the buds open [7] .