The influence of inoculation of seed with biopreparations, spraying crops with the preparation Biocomplex-BTU (solution) is presented in the article. This influence depends on the background of fertilization on the disease and productivity of the spring barley varieties, i.e. Avgii and Voievoda. The resistance of the spring barley to pathogens of mesh helminthosporiosis and root rot depending on fertilization, inoculation of seeds and the treatment of crops with biopreparations under the conditions of the Right-bank Forest-steppe of Ukraine are determined. It was investigated that the inoculation of barley seeds with biopreparations Agrobakteryn (Agrobakterium radiobakter 10), Polimiksobakteryn (Paenibacillus polymyxa КВ with the titer of 5х10cells/g dry form) reduced the infestation of plants with root rot. It has been found that the treatment of seeds with biopreparation (Bacillus subtilis 221 – 40±10%, Azotobacter 30±10%, Paenibacillus polymyxa 10±5%, Enterococcus 10±5%, Lactobacillus 10±5% with the titer of 1–3x107 1х108 –1х109 CFU/cm2 ) reduces the development of the ordinary root rot by 59,4–86,2 and 71,4–83,3%, depending on the type and the background of a fertilizer. Application of biopreparation Biocomplex-BTU (solution) in the phase of entering the tube of barley varietie. Avgii and Voievoda diminishes the development and distribution of mesh helminthosporiosis. We have determined that the dressing of spring barley seeds with bacterial preparations exerts a positive influence on its yielding capacity. The highest yielding capacity can be achieved through the complex usage of bacterization a mineral fertilizers. It was established that pre-sowing inoculation of spring barley seeds increases the grain yield by 2,0– 10,7%, depending on the type and the background of a fertilizer. Under the effect of mineral fertilizers both individually and in combination with green manure, grain yield increased by 26,2–37,7% compared with control. The treatment of crops of spring barley varieties Avgii and Voievoda with biopreparation Biocomplex-BTU (solution) promotes an increase in grain yield by 1,1–7,4% depending on fertilization and inoculation of seeds

Keywords: barley, biopreparations, fertilizers, diseases, yield