[FORMATION AND FUNCTIONING OF SYMBIOTIC SYSTEMS AND RHIZOSPHERE MICROBIOCENISIS OF SOYBEAN UNDER VARIOUS FUNGICIDES APPLICATION].

The Relevance. At the recent years in soybean crops the quantity of plant pathogenic fungi has increased. The fungicides of systemic and contact action have been applicated intensively against of them. After introducing into the soil fungicides and/or their deg- radation products can to disrupt the activities of non-target objects - beneficial soil mi- croorganisms, inhibit nodulation process and the nitrogen-fixing activity of diazotrophs. The purpose of the work was to investigate the impact of combined application of fungi- cides with inoculation on the soybean symbiotic system and rhizosphere microorganisms. The Methods. The microbiological and statistical methods, gas chromatography method. The Results. Inoculation of seeds by the highly active Bradyrhizobiumjaponicum UCM B-6035, UCM B-6018 and UCM B-6023 strains the activity of nitrogen-fixing symbiotic systems increased by 1.4-3.4 times in comparison with the variant without of fungicides application and bacterization. Seed treatment by Vitavaks 200 FF fungicide caused a de- crease of'nitrogen-fixing activity of rhizobia industrial strains in symbiosis with soybean by 3-5 times. The seeds inoculation by B. japonicum UCM B-6035 strain promoted to reduce the negative impact of the Maxim Star 025 FS fungicide on the nitrogenase activity of nodulation apparatus. The positive effect of seeds bacterization was observed in the in- crease of the quantity of rhizosphere microorganisms of main ecological trophic groups. In the variant with seed treatment by Maxim Star 025 FS and Kinto duo fungicides was found a decrease in the number of microorganisms of studied groups in comparison with the control variant; the Vitavaks 200 FF fungicide application promoted to improve of these microorganisms development compared with the variant without the fungicides application and bacterization. At the inoculation of rhizobia industrial strains the negative effect of the Maxim Star 025 FS and Kinto duo fungicides to oligoazotrophic and prototrophic micro- organisms was not observed. The Conclusion. The symbiotic system of variant with the combined application of the Kinto duo fungicide with B. japonicum UCM B-6023 strain characterized by the highest nodulation and nitrogen-fixing activity.

[INFLUENCE OF FUNGICIDES COMPLEX INOCULUM EKOVITAL ON RHIZOSPHERE MICROBIOCENOSIS, DISEASES RESISTANCE AND SOYBEEN PRODUCTIVITY].

It has been investigated the effect of fungicide with systemic action of Vitavaks 200 FF, Maxim Star 025 FS, Kinto duo and the complex inoculum Ekovital on rhizospheric microbial communities, diseases resistance and soybean productivity of Annushka biovar. The combined use of fungicides and inoculation has contributed to better formation of nodulation apparatus (the number of nodules on the roots was increased in 1.3-2.8 times), resistance increase to soybean pathogens septoriosis and ascochitosis, plant productivity increase on 17.4-32.1% relatively to the variant with Ekovital. The efficiency of the combined treatment of seeds against septoriosis and ascochitosis has become 45.8-64.1% and 82.0-95.1% respectively, in the flowering-early fruiting stage and 38.1-60.6% and 70.3-82.1% respectively, in the loading beans phase.

[Comparative analysis of isolation methods of DNA from rhizosphere soil for research of microbiocenosis].

The comparative analysis of different methods for the isolation of microbial DNA from ordinary black earth and dark-gray podzolic soil of soybean rhizosphere was carried out. All preparations of DNA which isolated from dark-gray podzolic soil after purification using highly dispersed silica (AppliChem, Germany) were suitable for 16S rRNA genes amplification with universal bacterial primers 11F i 1492R. For DNA extraction from ordinary black earth suitable for PCR DNA preparations were obtained using two of the six investigated methods. Isolation of DNA using a commercial Power Soil DNA Isolation Kit (MO BIO, USA) can get a small amount of DNA suitable for molecular studies without further purification procedures.