Cytological effects of pesticides. XII. Effects of the phosphorothioate insecticide dursban on the mitosis of Vicia faba

The effects of the phosphorothioate insecticide “dursban” have been studied on root-mitosis of Vicia faba. Two types of treatments were carried out using different concentrations of the insecticide: Seed-soak-treatment for 24 hours, and roottreatment for 4 hours. Both treatments induced a significant percentage of abnormal mitoses, the percentage of which increased as the concentration of the experimental agent increased. The different treatments with dursban did not effect the mitotic index. Disturbed meta- and anaphases where the chromosomes spread irregularly over the cell dominated. Lagging chromosomes and chromosome fragmentation were also observed. Micronuclei were observed in the different mitotic stages.