BIOLOGICAL CONTROL OF RASPBERRY SPUR BLIGHT CAUSED BY <i> DIDYMELLA APPLANATA </i> USING A MIXTURE OF MICROBIAL AGENTS

Abstract

The article presents the results of three-year field trials of the mixed experimental bio preparation Phytop 26.82, consisting of the bacteria Bacillus amyloliquefaciens RCIM (All-Russian Collection of Industrial Microorganisms) B 10642, Bacillus licheniformis RCIM (All-Russian Collection of Industrial Microorganisms) B 10562, Bacillus subtilis RCIM (All-Russian Collection of Industrial Microorganisms) Microorganisms) B 10641, nematophagous fungi Arthrobotrys oligospora RCIM (All-Russian Collection of Industrial Microorganisms) F-1141 and Duddingtonia flagrans VKM F-2574, as well as the entomopathogenic fungus Beauveria bassiana, against the central raspberry disease - purple spot in the production plantations of the culture. The concentration of the mixture was 105 CFU/ml. As a comparison, we used the chemical fungicide Topaz, EC (emulsion concentrate) at 0.1% concentration. Previously, the authors evaluated the effect of this microbial mixture on the pathogen Didymella applanata in laboratory conditions, which was the basis of field trials. It was found that when one-year-old raspberry shoots were affected by purple spotting, the treatment of vegetative plants reduced the development of the disease by almost three times for more than a month after applying the microbial mixture. Furthermore, the prevalence of the disease decreased by two times or more relative to the control. The biological efficiency of the experimental bio preparation Phytop 26.82 reached 72.7%, comparable to the Topaz chemical fungicide. This mixed microbiological preparation is promising as an environmentally friendly means of protecting raspberries from purple spotting while suppressing other potential diseases and pests on this crop and reducing the undesirable influence of abiotic environmental factors.