INFLUENCE OF THE INSECTICIDE CARBOFURAN ON THE PRODUCTION AND OXIDATION OF METHANE IN A FLOODED RICE SOIL

Applications of a commercial formulation of carbofuran, a carbamate in secticide, at rates of 2 kg and 12 kg active ingredient ha(-1) to floo ded fields planted to rice led to significant inhibition of methane em ission. Likewise, laboratory incubation studies showed that carbofuran applied at low rates (5 and 10 mu g g(-1) soil) inhibited the net met hane production relative to that of the control, but stimulated it whe n applied at a rate of 100 mu g g(-1) soil. Interestingly, carbofuran increased the oxidation of methane when applied at low rates and inhib ited it when applied at a rate of 100 mu g g(-1) soil.