Degradation of carbofuran and carbaryl by a suspension from a flooded soil incubated at 35°C and retreated with carbofuran

Abstract

An enrichment culture was prepared by repeated additions of carbofuran to a flooded alluvial soil that was incubated at 35°C. In a mineral salts medium inoculated with this enrichment culture and then incubated at 35°C, more than 90% of the14C-carbofuran and14C-carbaryl were lost within 5 and 3 days of inoculation respectively; during the same period no appreciable loss of both insecticides was noticed in the uninoculated medium. Carbofuran was degraded by the enrichment culture at a concentration as high as 1000 μg ml−1. Addition of ammonium nitrogen to the medium temporarily slowed down the degradation of carbofuran by enrichment culture.