EFFECIENCY OF TWO ORGANOPHOSPHOURUS INSECTICIDES ON THE CITRUS WHITEFLY, DIALEURODES CITRI WITH SPECIAL REFERENCE TO THEIR RESIDUAL BEHAVIOUR ON ORANGE FRUITS.

Document Type : Original Article

Authors

1 Central Agricultural Pesticides Laboratory, Agricultural Research Centre, Dokki, Giza, Egypt

2 Plant protection Research Institute, Agricultural Research Centre, Dokki, Giza, Egypt

Abstract

Two experiments were carried out during the two successive years 1986, 1987 in Tant EI-Gizierah, Qalubia governorate to evaluate the efficiency of two organophosphorus insecticides against the citrus whitefly, Dialeurodes citri on navel orange trees. Selecron (profenofos) at the rate of 0.075% and Tokuthion 500 (prothiophos) at the rate of 0.1 5% were applied on orange trees and an untreated area was left for comparison. Both insecticides gave satisfactory results and no phytotox‌icity was obseved after application. Residues of either pesticide were mainly detected on and in the orange peel, while the amounts penetrated into the pulp were negligible. Pre - harvest intervals of 21 days and zero day were determined for prothiophos and profenofos according to the maximum residue limits of 0.05 and 3.0 ppm, respectively . Persistence of either chemical followed a similar pattern but the RL50 was 6.0 days for profenofos and 10.5 days for prothiophos. As the amounts of residues determined in the orange peel were relatively high at the pre - harvest intervals and as it might be used in flavour and jam manufacture, further studies should be directed to inves‌tigate the effect of washing, heat and cooking processes on the disap‌pearance of pesticides residues from the peel.

Files

Share

How to cite

Statistics