Microbial degradation of pirimiphos-methyl and carbaryl by pure cultures of two soil fungi

Microbial degradation of pirimiphos-methyl and carbaryl was studied in a pure liquid culture media of either Rhizoctonia solani or Fusarium oxysporum. The detection limits ofpirimiphos-methyl and carbaryl by the utilized method were 97 and 75 ppb. High performance liquid chromatographic analysis revealed that both pirimiphos-methyl and carbaryl disappeared in part from the media enriched by R. solani or F. oxysporum. The amounts ofpirimiphos-methyl reached 25.6 and 16.9%, meanwhile, carbaryl amounts were 15.2 and 11.2% of the applied doses after 21 days in the media cultured with R. so/ani and F. oxysporum, respectively. The half-life values (Tl/2) for pirimiphos-methyl and carbaryl were 8.0 and 6.7 days, respectively in the culture amended with R. solani, while in case of F. oxysporum they were 6.8 and 6.9 days, respectively. The amounts of carbaryl declined with time faster than pirimiphos-methyl. Data showed that F. oxysporum was capable of degrading pesticides under investigation much faster than R. solani