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The different methods and application rates of an inoculum powder of sunflower Phoma rot pathogen Plenodomus lindquistii Gruyter, Aveskamp & Verkley for an artificial infection of seeds in the laboratory in soil were studied, the results are presented. The following methods of application of Phoma inoculum powder into soil were studied: into row, mixtures with soil, and on the bottom of a growth tray covered with a filter paper under soil. The application rates of an inoculum powder were 2.5 and 5.0 g per a row of 11 cm length; 5.0 and 10.0 g per 600 g of soil – mixing with soil and on the bottom of the growth tray. The method of application of the inoculum powder into a row in a rate of 5.0 g when the most seeds perished before sprouting were considered to be an optimal one. The sunflower infection with Phoma rot pathogen was weak in variants where pathogen powder was mixed with soil or placed under soil on the bottom of the growth tray. [ABSTRACT FROM AUTHOR]

Phytosanitary instability of agrobiocenoses and deterioration of the general ecological situation suggest increasing use of biological plant protection means. The purpose of this research was to study the mechanism of antagonistic action of the promising antagonist strain 11-1 Bacillus sp. on the sunflower Phoma rot pathogen Plenodomus lindquistii Gruyter, Aveskamp & Verkley, as one of the stages of developing elements of microbiopreparation production technology. The interaction of the promising antagonist strain with the Phoma rot pathogen before colony adhering was expressed in the formation of spherical swellings of apical parts of hyphae, giant cells, vacuolization, and compression of cytoplasm in mycelium of the pathogen. After colony adhering, we noted sorption of bacteria along pathogen hyphae, which resulted in even greater compression of cytoplasm, destruction of a cell wall, release of contents, dissolution of substrate, and vesiculation of aerial mycelium. Death of the pathogen mycelium under co-cultivation with bacillus-antagonist occurred on the seventh-eighth day. [ABSTRACT FROM AUTHOR]

To develop environmentally safe multifunctional biological preparations, we carried out the primary screening of bacterial strains (from the collection of the biomethod laboratory of V.S. Pustovoit All-Russian Research Institute of Oil Crops) against the sunflower dry rot pathogen Rhizopus oryzae Went & Prins. Geerl. by the method of double or reciprocal cultures. 17 strains of the Bacillus genus exhibited antagonistic activity against the sunflower dry rot pathogen with two types of mechanism of action (competition for feeding area and antibiosis). Strains 01 kor f and D 1-1 Bacillus sp. competed for surface feeding area and inhibited the growth of aerial mycelium of the pathogen. We observed the maximum sterile zone in three strains: 3-3 Bacillus sp. and K 1-1 B. subtilis – 4.0 mm, and P-9 B. polymyxa – 3.0 mm. 6 bacterial strains of the genus Pseudomonas had antagonistic activity against the dry rot pathogen with one type of mechanism of action – antibiosis. Strain 12-2 Pseudomonas sp. had the largest sterile zone on potato sucrose agar (PSA) (5.5 mm), and strains 14-4 and 15-1 Pseudomonas sp. had the largest sterile zone on the King B medium (5.0 and 6.0 mm). [ABSTRACT FROM AUTHOR]

The article presents the results of development of technology elements of application of the laboratory samples of microbiopreparations in the preparative form of wettable powder (WP) based on the promising producer strains against the pathogen of oil flax Fusarium blight Fusarium oxysporum var. orthoceras on the background of artificial inoculation in a humidity chamber in vitro, depending on the application rate. On the backgrounds of flax inoculation with the Fusarium blight pathogen in control without treatment of 70.0 and 90.0 %, we established the optimum application rates for the laboratory samples of WP microbiopreparations: based on the fungal producer strain T-1 Trichoderma sp. with a titer of 2.3×1010 CFU/g – 0.05 kg/t, with the effectiveness of 71.4-57.2 %, respectively; based on the bacterial producer strain 11-3 Bacillus sp., with a titer of 5.5×1012 CFU/g – 0.3 kg/t, with the effectiveness of 100 and 85.7 %, respectively. [ABSTRACT FROM AUTHOR]

Compatibility of strains-producers of microbiopreparations with pesticides recommended for application on oil flax is determined. The strains-producers of microbiopreparations 11-3 Bacillus sp. and Т-1 Trichoderma sp. Are compatible with fungicides, insecticides, and a herbicide (TMTD, WSC (thiram, 400 g/l); Raxil Ultra, CS (tebuсonazole, 120 g/l); Faskord, EC (alpha-cypermethrin, 100 g/l); Rogor-S, EC (dimethoate, 400 g/l); Egida, SC (mesotrione, 480 g/l). This allows applying mixtures on their basis in an integrated crop protection. A partial compatibility of a fungus strain Т-1 Trichoderma sp. with a fungicide Raxil Ultra, CS is an exclusion. Bacterial and fungus strains-producers are not compatible with fungicides Redigo Pro, CS (prothioconazole, 150 g/l, tebuсonazole, 20 g/l) and Tebu 60, ME (tebuсonazole, 60 g/l). [ABSTRACT FROM AUTHOR]

The article presents the results of the development of technology elements of microbiopreparation laboratory samples application in the preparative form of wettable powder (WP) based on two promising producer strains against the pathogen of oil flax Fusarium blight Fusarium oxysporum var. orthoceras on the background of artificial inoculation in the soil depending on application rates. We established the optimum application rates for laboratory samples of WP on the background of oil flax inoculation with Fusarium blight pathogen of 67.5 % in control without treatment: based on fungal producer strain T-1 Trichoderma sp. – 0.05 kg/t; based on bacterial producer strain 11-3 Bacillus sp. – 0.3 kg/t. The laboratory sampleof WP based on the bacterial strain showed higher effectiveness against the pathogen of oil flax Fusarium blight. [ABSTRACT FROM AUTHOR]

The article presents the results of primary screening of a collection of fungal antagonist strains to the most widespread and harmful in the Krasnodar region isolate of dry rot pathogen Rhizopus oryzae Went & Prins. Geerl. We conducted the screening by the method of double or reciprocal cultures to develop environmentally safe microbiological preparations of multifunctional type of action. The evaluation of 30 fungal antagonists on two nutrient media (potato sucrose and Rudakov's) established 14 strains with one or more types of mechanisms of antagonistic action against the dry rot pathogen. 7 strains had a double mechanism of action (competitionfor feeding area and hyperparasitism). Of these, six strains (T-1, T-2, T-3, Т-4, Т-5 Trichoderma sp., and А-1 Basidiomycota) showed activity on both media. The growth area of these strains was 100%, with hyperparasitic area sizes ranging from 35.3 ± 0 to 43.4 ± 2.2 cm2. We observed the maximum hyperparasitic zone in the strain A-1 Basidiomycota – 43.4 ± 2.2 cm2 on the potato sucrose medium and 40.2 ± 4.5 cm2 on the Rudakov's medium. We observed the maximum sterile zone to the dry rot pathogen in the strains Xk-2 and Xk-1 Chaetomium olivaceum (5.0 ± 0 and 5.5 ± 0.6 mm) on the potato sucrose medium, and Pbc-1 Penicillium brevi-compactum and Xk-2 Chaetomium olivaceum onthe Rudakov's medium (3 ± 0 mm). [ABSTRACT FROM AUTHOR]