THE POTENTIAL EFFECT OF ORGANOPHOSPHORUS INSECTICIDES ON PEROXIDASE ENZYME ACTIVITY IN TOMATO PLANTS

Abstracts

In this study, the effect of three organophosphate insecticides on the peroxidase activity in growing tomato plants under greenhouse conditions was investigated. The peroxidase activity was significantly increased under the influence of insecticide treatments with increasing concentrations of treatments, 2.0 fold of the recommended doses of the common uses organophosphorus insecticides (methidion, acephate and parathion) in Al-Hassa province. However, the significant interactions between insecticide and doses were observed at 20 days after spraying and then decreased after 40 days in treated plants compared with untreated plants. The most affecting insecticides were parathion and acephate, while methidion was the lowest. However, the parathion caused a highest peroxidase activity that reflected as intensity in electrophoresis gel and in concentration of peroxidase. The stress of organophosphate-insecticide in tomato plants was evaluated by the results of specific peroxidase activity in the treated tomato plants. The uses of electrophoresis and spectrophotometer approaches to measure the peroxidase allowed to assess different features of the enzymatic activity. These results definite that; in addition to a great number of peroxidase enzyme isoforms and each isoform is activated depending on the chemical structure and properties of the insecticide. Thus the misuse of pesticides affects normal plant growth, which could result in reduction of yield or quality.

Keywords :

Peroxidase activity, organophosphorus insecticides, electrophoresis, enzyme isoform, tomato. Please see full information

isoform, tomato.