Genotoxicity of two organophosphorous pesticides : dimecron and diazinon in Aspergillus terreus

Abstract EN

In attempt to investigate the genotoxicity and the mode of action of the organophosphorous pesticides ; Dimecron (2-chloro-N,N-diethyl-3-hydroxycrotonamide dimethyl phosphate) and Dizinon [o,o-diethyl o-(2-isopropyl-4-methyl-6-pyrimidyl) phosphorothioate], the conidial spores of Aspergillus terreus were treated by four different concentrations (including the field concentration) of each pesticide individually as follows : Conidia were treated with 0.1 ml / 10 ml, 0.15 ml / 10 ml, 0.2 ml / 10 ml and 0.25 ml / 10 ml conidial suspension of the pesticide Dimecron, and survival andmutation frequencies were calculated to find out the optimal dose for induction of mutation (by scoring the auxotrophs if possible).

In the same way, conidia were treated with 0.075 ml / 10 ml, 0.1 ml / 10 ml, 0.15 ml / 10 ml and 0.2 ml / 10 ml-conidial suspension of the pesticide Diazinon, and the same procedure above mentioned was followed.

As a results, it was found in both of the two experiments that, with increasing of Dimecron or Diazinon concentration and exposure time, a decrease in survival percentage and an increase up to a certain limit in mutation frequency were always observed.

The optimal dose for inducing mutation by Dimecron was found to be 0.2 ml/10 ml-conidial suspension for 30 min.

and 0.15 ml / 10 ml conidial suspension of Diazinon for 30 min.

too.