The purpose of this work was to evaluate the introduction of microorganisms capable of destroying toxic compounds to seed germination. To develop methods for soil restoration using biological products, experiments were conducted on the introduction of isolated soil bacteria that exhibit the ability to grow on diesel fuel to cleanse the soil. The experimental design included the following: 1) control, 2) sterile soil + diesel fuel (DF), 3) sterile soil + DF + bacterial suspension (BS), 4) non-sterile soil + DF, 5) non-sterile soil + DF + BS.

From the soil sample, 45 microbial cultures were isolated, of which 13 can use diesel fuel as a carbon source. DF was added to the soil in an amount of 5% (w/w) and mixed with the soil until homogeneous. BS for soil treatment was prepared by mixing suspensions of each bacterial culture grown to 1.5 p.u. (600 nm), 1 ml each. In total, 13 ml of the resulting mixture was added to samples of sterile and non-sterile soils, and the soil was mixed again. The effectiveness of cleaning was assessed by the germination of wheat seeds and an assessment of the general toxicity of the soil using the recommendations of the Russian Federation, 1.39.2007.03223 [chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://www.gostrf.com/normadata/1/4293842/4293842245.pdf].

As a result, it was revealed that the soil with 5% (w/w) DF was characterized as slightly polluted throughout the experiment. The growth rates of wheat in DF-treated soil were 32% and 34% with sterile and non-sterile soil, respectively, while the growth rates in DF- and BS-treated soil were 86% and 88%, respectively. In the control sample, it was 82%. Thus, the introduction of a bacterial suspension of diesel-fuel-degrading strains, although it did not significantly reduce the toxicity of the soil, contributed to a significant increase in germinating wheat seeds.