A. V. Rama Subbaiah^1,, Atmakuru Ramesh¹

Oxyfluorfen widely using in paddy field and unknowingly polluting the soil. The present study soil microorganism’s carbon and nitrogen transformation test was conducted in loamy sand soil, the experiment conducted as per Organization for Economic Co-operation and Development (OECD) Guideline 216 and 217. The application of oxyfluorfen 23.5% EC applied dose rates T0-Control, T1-100 g a.i/ha (active ingredient/hectare) and T2-1000g a.i/ha soil dry weight. The test concentrations were one and ten times the recommended field application rate. After application of the soil boxes were incubated at 20°C in dark conditions. The soil samples were collected at 0 (within the 6 hours), 7, 14, and 28 days after imposing the treatment. Carbon transformation (short-term respiration) was determined by amended the glucose to soil samples. Short-term respiration was calculated based on oxygen consumption (BOD) during the experiment. Soil nitrification was determined by measuring the NO3- contents of aqueous soil extracts using calibrated ion-sensitive electrodes and the Orion expandable ion analyzer. The deviation in respiration rates and nitrification compared to controls after applying the test item after 28 days 2.8 % and 7.0 % for the; -3.12% and -7.18% for the respiration rates and nitrification respectively T1 and T2 test concentrations. There was no significant variation between the treatment and control samples.

carbon, nitrogen, HPLC and Loamy sand