Correlation analysis of indicators of biotechnological process of vermicultivation under the influence of biologically active substances

Abstract

In the process of utilization of agricultural organic waste by the method of vermiculture, humus is formed. It is a valuable biofertilizer because it contains nutrients of organic and inorganic origin for plants. Of particular importance are humic substances that are involved in the formation of the plant organism. The search for new ways to increase the enzymatic activity in the intestines of vermiculture and the impact of processes on the accumulation of humic substances in biofertilizers during vermiculture may be promising, which may provide greater use of compost in agricultural production. The aim of the study was to establish correlations between the content of humic substances in biohumus and the activity of hydrolytic enzymes in the homogenate of vermiculture under the influence of Humilide in the process of vermiculture. Methods. The research was conducted in the conditions of the vermifery of LLC “Natural Biotechnology” in Zaporizhzhya. Biohumus and a hybrid of the California red worm were used as the object of the study. The nutrient substrate was a mixture of fermented cattle manure and waste oyster mushrooms. Burts of nutrient substrate were populated with vermiculture at the rate of 5–7 thousand per 1 m2. Control and experimental burts were distinguished, which differed in that the study was supplemented with the biologically active additive Humilid (15 mg/kg) in the form of a solution once a month, and in the control – the same amount of water. Selection of vermiculture and compost from control and experimental plots was performed on days 135 and 180 of the study. The amount of humic substances was determined in the prepared biohumus samples. Red California worms with an uncleaned intestine were used to obtain a homogenate in which enzymatic activity was determined. Statistical calculations were performed using the editor “Microsoft Excel”. Results. According to the results of correlation analysis, it was found that almost all the studied parameters of the control and experimental groups have a correlation of varying degrees. At day 135 of the study, the correlation coefficient between the indicators of humic substances, both watersoluble and alkali-soluble, and the cellulosolytic activity of the homogenate of the biomass of worms of the control group showed no connection. At the same time, there is a weak positive relationship between these indicators of the experimental group (r = 0.27 and r = 0.23), which is explained by the accumulation of humic substances in biohumus under the influence of Humilid and the growth of enzymatic activity. At 180 days of the experiment, a very strong positive correlation was observed in both the control (r = 0.96) and experimental (0.92) groups between the indicators of water-soluble humic substances in biohumus and cellulosolytic activity of vermiculture biomass homogenate. Regarding the correlation between the control (r = 0.77) and experimental (r = 0.78) groups between the indicators of alkali-soluble humic substances and the cellulosolytic activity of red California worm homogenate for 180 days of the experiment, it is strongly positive. Conclusions. According to the results of correlation analysis of humic substances content and enzymatic activity of vermiculture homogenate, it was found that on 135 days of vermiculture in the experimental group there was a weak correlation, while in the control connection is almost absent. At 180 days of the study, the strength of the correlation bond is stronger in both control and experimental groups, which is due to the accumulation of humic substances in compost and increased enzymatic activity of red California worm biomass homogenate during vermiculture.