Persistence of carbofuran in two Malaysian soils
G.H.N. FarahaniA, Zuriati ZakariaA, Aini KuntomB, Dzolkifli OmarC and B.S. IsmailA
A Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor, Malaysia.
B Malaysian Palm Oil Board, No.6, Persiaran Institusi Bandar Baru Bangi, 43000 Kajang, Selangor, Malaysia.
C Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.
Summary
Persistence of carbofuran in two Malaysian soils namely the Bagan Datoh and Labu soils was studied under laboratory conditions at a constant temperature of 30°C. Air-dried soil was sieved and then spiked with 10 µg g-1 of carbofuran at three different moisture levels, namely 100%, 90% and 60% field capacity. It was observed that the half-lives of carbofuran in the Labu soil samples (which are low in organic matter content) at 100%, 90% and 60% field capacity were 57.28, 38.51 and 115.52 days respectively. However the corresponding half-lives of carbofuran in the Bagan Datoh samples (which are high in organic matter content) at 100%, 90% and 60% field capacity were 192.54, 141.46 and 203.87 days respectively. The half-life recording of carbofuran in autoclaved Bagan Datoh and Labu soil samples were 147.5 days and 301.37 days respectively at 100% field capacity and at a constant temperature of 30°C. The degradation of carbofuran followed a first order kinetic reaction. The results of this study showed that soil moisture content, micro-organisms and the organic matter content (OM) affected the degradation of carbofuran in both soils studied.
Key words: Carbofuran, insecticide, dissipation, half-life, soils, water content, pH.
Plant Protection Quarterly (2008) 23 (4) 179-183.