Soil microorganisms' carbon transformation test for Picoxystrobin 25% SC (w/v) in loamy sand soil

Abstract

The effect of Picoxystrobin 25% SC on soil microorganisms (carbon transformation) was assessed in a test that measured induced respiration rate following the application of Picoxystrobin 25% SC to soil. Picoxystrobin 25% SC was incubated in loamy sand soil over a period of 28days for the carbon turnover at 1-fold and 5-fold concentrations, equivalent to 0.340mg/kg dry weight (T1) and 1.700mg/kg dry weight (T2) on product basis, respectively (corresponding to a field application rates of 400mL/ha and 2000mL/ha). Control consists of soil treated with equivalent quantity of distilled water and it was also incubated in the dark along with the treated soil samples. Carbon transformation was determined by short term respiration of soil microorganisms by amending soil samples with glucose. The oxygen consumption (BOD) during short term respiration of soil microorganisms in soil samples was measured up to 12 consecutive hours following addition of glucose on days 0, 7, 14 and 28 after application of Picoxystrobin 25% SC. In loamy sand soil respiration study at the end of the 28th day, deviations in respiration rates compared to controls after applying the test item to soil were −18.34% and −19.55% for the test concentrations of 0.340mg and 1.700mg of Picoxystrobin/kg soil dry weight, respectively. The dose concentrations (T1 and T2 levels) of Picoxystrobin 25% SC ware determined by validated HPLC method.