title: Degradation of [14C]photodieldrin by Trichoderma viride as affected by other insecticides.
abstract: Various soil fungi were tested for their capacity to degrade the insecticide [14C]photodieldrin. Of nine species investigated, Trichoderma viride was the only one which degraded the insecticide to an appreciable extent into water-soluble, non-insecticidal compounds within 4-5 weeks. These products amounted to 32-41% of the radiocarbon applied to the culture media. The degradation was a function of live mycelia, which metabolized the insecticide and excreted water-soluble compounds into the culture media. Since soils usually contain a mixture of pesticide residues, the effects of several chlorinated hydrocarbon insecticides on the capacity of the fungus to degrade [14C]photodieldrin were studied. Thus, in fungal cultures treated with compounds structurally similar to photodieldrin, such as aldrin and dieldrin, only 4-17% of the applied radiocarbon was water-soluble and more photodieldrin remained. In controls, however, 35% of the applied radiocarbon was in the form of water-soluble products and less photodieldrin remained. The degradation of [14C]photodieldrin by T. viride, with time, was associated with a continuous decline of hexane-soluble radiocarbon and a steady increase of water-soluble metabolites, which appeared in the fungal media. The amount of hexane-soluble radiocarbon in mycelia was directly related to the fungal mass.
mesh_terms: D001673:Biodegradation, Environmental; D002250:Carbon Radioisotopes; D004026:Dieldrin / Q000378:metabolism*; D005658:Fungi / Q000378:metabolism*; D007306:Insecticides / Q000494:pharmacology; D003904:Mitosporic Fungi / Q000378:metabolism*; D012988:Soil Microbiology; D012995:Solubility; D013045:Species Specificity; D014242:Trichoderma / Q000378:metabolism*
chemical_list: D002250:Carbon Radioisotopes; D007306:Insecticides; D004026:Dieldrin