THE INFLUENCE OF HUMIC ACIDS IN THE PRESENCE OF OIL-DEGRADING MICROORGANISMS OF THE GE-NUS RHODOCOCCUS ON THE SOWING QUALITIES OF COCKWEED IN OIL POLLUTION

Abstract

By the method of biotesting, it has been established that the addition of oil-degrading microorganisms of the genus Rhodococcus to the soil contaminated with hydrocarbonshas a positive effect on morphogenesis and sowing qualities of the cockweed test culture, which is associated with the microbiological oxidation of oil by bacteria of the studied strains. It was revealed that a positive effect was observed in 5 of 8 variants of the experiment on the medium with hexadecane with the joint introduction of humic acids and microorganisms. Under the conditions of oil pollution, the introduction of Rh. erythropolis X5 and Rh. erythropolis S67 microorganisms into the substrate with the addition of humic acids as a whole has a stimulating effect on the morphogenesis and sowing qualities of cockweed. It should be noted that it was in the “oil + humic acids + microorganism” variant that the indicators were obtained that maximally exceeded the values of the contaminated control. Reducing the toxicity of oil and hexadecane, and in some cases, the complete removal of the negative effects of toxicants in the relation to the test culture are apparently connected with the intensification of the process of oil biodegradation due to the stimulating effect of humic acids on the microorganisms. It is proved that the introduced humic acids act as adaptogens in the relation to the microorganisms Rh. erythropolis X5 and Rh. erythropolis S67, increasing their resistance to stress loads under conditions of oil stress. Thus, the results show that the introduction of humic acids can contribute to more effective biodegradation of oil pollution of soils. At the same time, in order to increase the efficiency of humic acids, the use of humic acids of sphagnum transitional peat + Rh.erythropolis X5, humic acids of sphagnum high-moor peat + Rh. erythropolis X5, humic acids of reed fen peat + Rh. erythropolis S67 in the conditions of oil pollution seems more promising. On a substrate with hexadecane, it is advisable to consider the use of humic acids of sphagnum high-moor peat, because in this variant, the parameters that maximally exceed the contaminated control were noted.