Abstract
Phosphorothionate and phosphate degradation was investigated as a factor which could influence the tolerance of organochlorine compound-resistant and susceptible mosquitofish ( Gambusia affinis) to parathion and methyl parathion. The greater toxicity of methyl parathion than parathion can be attributed in part to a higher rate of degradation of methyl paraoxon than paraoxon (7-fold), but not to any difference in phosphorothionate dearylation. Resistant fish possess higher levels of microsomal mixed-function oxidases which can degrade methyl parathion (1.3-fold); these higher levels could contribute to the increased methyl parathion tolerance by this population over the susceptible population. Environmentally induced tolerance to parathion in the resistant population may be the result of increased levels of parathion degradation by induced mixed-function oxidases which can dearylate parathion. The increased tolerance of either insecticide by the resistant population is not caused by degradation of the phosphates by phosphotriesterases.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.