Pesticide Residues As Affected By The Crop, Season And Method Of Application

Pesticide residues after application on vegetable plants should be follwed to determine the waiting period between application and harvesting to be sure that the residues are below the tolerance levels and the edible parts became safe for human consumption . The two organophosphorus insecticides, profenofos, and pirimiphos - methyl are widely used in Egypt to control some economic insects such as white fly, aphid and grass hoppers especially on vegetable plants . This work aimed to study the behaviour of the aforementioned insecticide residuse in squash and tomato fruits as affected by the season and the used spraying equipment (back spray motor, knap sack sprayer and ground spray motor). The effect of peeling and wshing in removing the residues of the two insecticides from treated fruits was taken in consideration . Comparison between the chemo - and biossay assessment of both cpmpounds was dealt with .