Investigation on the reduction of Orvego® fungicide (ametoctradin + dimethomorph) residue levels used to control tomato downy mildew disease in Mazandaran province
Subject Areas : Plant ProtectionMohsen Morowati 1 * , Abbas Ali Ravanlou 2 , Vahideh Mahdavi 3 , ُSeyed Ali Reza Dalili 4
1 - Associate Professor, Pesticides Research Department. Iranian Research Institute of Plant Protection (IRIPP), Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
2 - Assistant Professor, Plant Diseases Research Department, Iranian Research Institute of Plant Protection, Agricultural Research, Education and Extension Organization, Tehran, Iran
3 - Associate Professor, Pesticides Research Department. Iranian Research Institute of Plant Protection (IRIPP), Agricultural Research, Education and Extension Organization (AREEO), Tehran, Iran
4 - Assistant Professor, Plant Protection Research Department, Agricultural and Natural Resources Research Centre of Mazandaran Province, Agricultural Research, Education and Extension Organization, Mazandaran, Sari, Iran
Keywords: chemical control, LC-MS/MS, MRL, Orvego®, pesticide residues,
Abstract :
In order to measure the residue of Orvego® fungicide (ametoctradin+dimethomorph) which was used by the dose of 80 ml/100 liters of water (the dose recommended by the producing company), 15 samples of treated tomatoes (5 samples in 3 replications) and one control sample were collected at 1, 2, 3, 5 and 8 days after spraying. Extraction of pesticides was carried out according to the national standard of Iran "measurement of pesticide residues" which recommends to use QuEChERS method of extraction. Pesticides were analyzed by LC-MS/MS and the determined values were compared with the national and Codex MRLs. The results obtained show that according to the MRL of ametoctradin, which is 1.5 mg/kg (Codex), the mean residue detected in the samples was less than the MRL one day after spraying. Dimethomorph has a MRL of 3 mg/kg (National), and the mean residue detected in the samples was 0.076 mg/kg, one day after spraying which is less than the MRL. According to the recommendation of the manufacturer of Orvego® and the references studied the pre-harvest interval (PHI) of Orvego® (Ametoctradin+Dimethomorph) is 1 day, which is confirmed in the present research. Therefore Orvego® used at a rate of 80 ml/100 liters with the PHI of one day could be recommended to control tomato downy mildew disease.