The tough sanitary requirements are applied towards the growing of potatoes for food purposes. The intensive farming systems based on chemicals have led to a significant land degradation, violation of the ecological balance of agro-ecosystems, deterioration in the quality of agricultural products, radionuclide and heavy metals  – carcinogens, pesticides, various chemical minerals contamination. The accumulation of xenobiotics by plants from the soil determines the extent of the initial inclusion in the food chain in the system: soil – agricultural crops – people. In recent years, the development of methods of environmental protection has studied as an alternative way to chemical methods of protection, affecting the ecology of the agrophytocenoses.

Multi-method study of the efficacy of the composition of biological preparations based on bacteria strains Pseudomonas fluorescence AR-33, Agrobacterium radiobacter 204, Enterobacter nimipressuralis 32-3 were not carried out or were studied fragmentarily  in growing potatoes, as well as their effectiveness in the application at all stages (treatment of tubers in spring, during the growing season, before the storage) in Ukraine.

The studying of conditions under which the cultivation and processing techniques have a minimum number of non-standard forms, diseased tubers was the purpose of investigation. The aim of research was to study the influence of abiotic factors, timing of planting, processing of chemical and biological agents on yield and its structure in Lviv region. The study was conducted during 2009-2012. Planryz was studied as biological preparation – Pseudomonas fluorescence strain AR-33, 2.0 l/ha, Diazophit (active ingredient – bacteria Agrobacterium radiobacter, 0,2 l/ha), Phosphoroenteryn – biological preparation based on phosphorus bacteria Enterobacter nimipressuralis 32-3, 0.2 l/ha. Phitotsyd was used as biological control (based on Bacillus subtilis, 1 l/ha). The tubers were treated by preparations before planting, before the storage and plants during the budding. Experiments conducted on the 1st term (27-30 April), 2nd (12-15 May). The study was conducted in 4 districts of Lviv region, which differ in their soil and climatic conditions: West Woodlands, Radekhiv area; West Zone of steppe, Zhovkivsky area; Carpathian Foothills area, Strysky area; Carpathian, Skole district. The crop was harvested the 3rd week of August – 2nd week of September. Repeated experiments – 3-5 fold. The third term of planting (late May) was unsuitable from the economic side (low yield), but because it has been excluded from the scheme of studies. The study was carried out by conventional methods. Statistical analysis of the data was performed by a computer program Excel.

It was found that the productivity and marketability, the standard fraction of potatoes tuber increased at treatment of biological preparations (Phitotsid, Planriz, Diazophit and Phosphoenterin) on the average in varieties and planting terms in Lviv region. In this case, the composition of the non-standard fraction changed due to a significant decrease of small, mechanically damaged and diseased tubers. The yield of potatoes exceeded the control in 1.3-1.7, and the number of infected tubers decreased in 2,1-5,4 times. The concentrations of Planriz 2.0-2.5 l/ha, and Planriz + Diazophit +PMB – 2.5+0.2+0.2 l/ha were the best among the variants. The 1st planting time in the third decade of April was the best due to the smaller number of tubers damaged by disease.

The using of Planryz, Diazophit and Phosphoenteryn softened the action of unstable weather conditions, especially the excess moisture, contributed to a more yield, high marketability of potatoes and non-standard potatoes in comparison with control. Using a mixture of  Planryz, Phosphoenteryn (PMB) and Diazophit as environmentally safe microbiological preparations based on microorganisms will improve phosphorus and nitrogen nutrition potatoes contribute to accelerate the growth process, strengthen the immune system of plants due to the production of biologically active substances that contribute to biocontrol of pathogens followed increase productivity and commercial quality potatoes. These properties make it possible to use these microbiological agents in Bioorganic agriculture. In the future study of plant resistance, biological products processed, with lesions pathogens that are important for the development of highly efficient environmentally friendly measures to protect plants from disease. The study of plant resistance, processed by biological preparation, at affect of pathogens is in the works in the future that are important for the development of highly efficient environmentally measures to protect plants from disease.

Key words: Solanum tuberosum L., microbiological preparations, marketability, diseased, stability