Rimsulfuron in Soil: Effects on Microbiological Properties under Varying Soil Conditions

Abstract

The effects of rimsulfuron a sulfonylurea herbicide on the growth and activity of soil microorganisms under laboratory conditions was investigated in two soils. The application rates were: 0.2, 2.0 and 20.0 mg a.i kg-1 soil. The lowest concentration tested was the label rate (0.2 mg a.i kg-1), and the other two were ten and hundred times higher. No adverse effects on microbiological processes were observed for the label rate. Decrease in microbial biomass carbon, dehydrogenase activity, fungi and bacteria in comparison with untreated control, were found at higher rates. The magnitude of these effects were generally slight and transitory.

Na dva tipa zemljišta, u laboratorijskim uslovima, ispitivan je uticaj herbicida rimsulfurona iz grupe sulfonilurea na brojnost i aktivnost zemljišnih mikroorganizama. Rimsulfuron je primenjen u koncentracijama 0,2, 2,0 i 20,0 mg a.s. na kilogram zemljišta. Najmanja ispitivana koncentracija (0,2 mg) odgovarala je količini koja se preporučuje za primenu, a druge dve su deset i sto puta veće od preporučene. Kada je primenjen u preporučenoj količini, rimsulfuron nije imao uticaja na ispitivane mikrobiološke parametre. Smanjenje mikrobiološke biomase ugljenika, dehidrogenazne aktivnosti, brojnosti gljiva i bakterija utvrđene su kod većih koncentracija rimsulfurona. Intenzitet ovih promena je, uglavnom, bio slab i prolaznog karaktera.