The elements of technology of application of the different preparation forms of microbiopreparations on the base of the perspective strains-antagonists Xk-1-4 Chaetomium olivaceum and B-12 Bacillus licheniformis against white rot of winter rapeseed

As a result of a graded screening strains Xk-1-4 Chaetomium olivaceum and B-12 Bacillus licheniformis were selected from a collection of the laboratory of biological methods of VNIIMK. These strains decompose actively sclerotia of white rot of rapeseed Sclerotinia sclerotiorum (Lib.) De Bary and possess growth-stimulating activity to this crop. The purpose of this work was to ascertain methods, dates and norms of usage of the different preparation forms of microbiopreparations developed on a base of selected strains-antagonists for decreasing of viability of sclerotia and infection of vegetating plants of win ter rapeseed. During the research the seeds were treated before sowing, and infected plant residues were treated after harvesting, before soil disking. The method of an artificial infection of rapeseed with a white rot pathogen developed by our laboratory was considered as the optimal one. It is modified by us method when rapeseed seeds are displayed on a wetted filter paper, then placed into Petri’s dishes on a white rot mycelium. In this case up to 80.0% of seeds were infected. The high efficiency of rapeseed seeds treatment with a biopreparation based on a strain of fungus Xk-1-4 Chaetomium olivaceum to control white rot pathogen was proved; the preparation form powder with a usage rate 3.0 kg/t (72.7%) had the highest biological efficiency. A possibility to decrease viability of white rot sclerotia at treatment of winter rapeseed residues with microbiopreparations developed on a base of the promising strains Xk-1-4 Chaetomium olivaceum and B-12 Bacillus licheniformis in summer and autumn, before soil disking is determined. In summer, application of microbiopreparations in form of powder with a usage rate 20.0 kg per ha (83.6-85.4%), and a liquid culture with a usage rate 50.0 l per ha (81.8-85.4%) was the most effective. When using these microbiopreparations in autumn, before soil disking, for treatment of plant residues the most effective usage rate was 30.0 l per ha (effectiveness was 79.9-82.3%).