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Studies on determination of the effect of herbicides on survivability of Plant Growth Promoting Bacteria have a strategic usefulness in determination of plant health and the fate of applied agrochemicals in agroecosystem. Antimicrobial potential was assessed using estimation of a minimum inhibitory concentration of the Roundup 360 SL against Pseudomonas sp. A quantitative analysis of bacteria was performed, and the tendency of physicochemical changes in the mineral medium was evaluated during long-term exposure to the herbicide. Furthermore, the antagonism of the SP0113 strain against F. culmorum and F. oxysporum under stress conditions caused by Roundup® 360 SL was verified. It was demonstrated that use of the undiluted and 2.6-fold diluted product resulted in the inhibition of growth of the investigated strain. Pseudomonas sp. SP0113 showed survivability and resistance to near recommended dose concentration of Roundup® 360 SL. The possibility of bacterial development on the Tryptic Soy Agar (TSA) medium at contact concentrations of 14.4 and 5.4 mg mL^-1, as per the diluents quantity declared by the producer, indicates the role of cofactors such as: adiuvant or pH, redox potential (mV) or salinity. They comprise pH change, oxidation and salinity that may be due to the reaction of the active substance of the herbicide with mineral nutrient ingredients. The high salinity of environment, as a result of the reactions with the ingredients contained in the medium, is characteristic for concentrations higher than those recommended in practice. Furthermore, it was found that glyphosate limits the growth of fungi of the Fusarium genus, which support plant protection using strain SP0113.

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The SP-A9 strain of Bacillus sp., which is most closely related to Bacillus subtilis, demonstrated excellent antifungal properties in laboratory analyses. The percentage of inhibition in the dual culture test was similar for all investigated phytopathogens (Fusarium culmorum, F. oxysporum and Monographella nivalis) at approximately 46%. The analyzed strain was found to be cellulolytic and strongly chitinolytic, and its biochemical properties indicate that it easily adapted to various environmental conditions. The strain's sporulation ability and high proliferation rate in acidic, alkaline, and highly saline environments (9% NaCl) further confirmed its adaptability to adverse conditions. In a pot experiment, the basic biometric parameters of spring wheat grain inoculated with Bacillus sp. SP-A9 were not modified, but a significant increase in grain yield was observed (by 18% in soil contaminated with F. culmorum and by 19% in soil contaminated with F. oxysporum). The increase in yield was correlated with the number of wheat plants, which suggests that the analyzed strain minimized the pathogen-induced inhibition of plant growth. Bacillus sp. SP-A9 can reduce economic losses resulting from diseases caused by fungi of the genus Fusarium and contribute to reduced use of crop protection chemicals, thus minimizing environmental pollution.