Gaupsin – this is a biological preparation intended for protecting apple trees. The preparation contains bacteria Pseudomonas aureofaciens Kluyver, strains B-306 and B-111, with a titre of not less than 10×10 cells/cm³. The manufacturer of the preparation is the company TOV «Zakhyst-Agro», located in Ukraine, Odesa region, Belyaevsky district, village Vasilivka. The preparation belongs to the category of biological plant protection agents and can be used to prevent apple tree diseases. Using the biological preparation helps improve plant health and reduces the need for chemical pesticides, making it an environmentally safe solution.