The effect of chlorsulfuron and MCPB-Na on the enzymatic activity of microorganisms

Sulphonylureic herbicides have a broad spectrum effect on weeds in relatively low doses and with a much reduced toxicity to livestock. In this study, two herbicides: dacsulfuron with the active substance chlorsulfuron (0.005–0.035 µg g-1 soil) and butoxone with the active substance MCPB-Na (0.005–0.035 mg L-1 g-1 soil) were investigated. The sAMples were collected from a depth of 0–20 cm from chernozem soil. The effects of the herbicides were estimated by measuring the activities of catalase, actual and potential dehydrogenase, urease and cellulase. All sAMples were incubated for 10 days at 27 °Cusing Stapp medium for the isolation and study of cellulosolytic bacteria. The inhibitory effect of the tested herbicides was the most intense on the enzymatic activities of urease and dehydrogenase. The most resistant cellulosolytic bacteria to the effects of dacsulfuron were Cellfalcicula fusca, C. viridis, Cellvibrio fulvus and Cellfalcicula sp., and for butoxone C. mucosa,C. viridis and C. fulvus.