The dissipation behavior of three pesticides, bifenazate, spirodiclofen and abamectin was studied in strawberry fruits using a modified QuEChERS extraction technique. The residues of the tested acaricides were determined under field conditions after 1 hour (zero days), 1, 3, 7, 14, and 21 days. The maximum residue limits (MRLs) were 2, 2, and 0.15 mg/kg for bifenazate, spirodiclofen and abamectin, respectively. The strawberry fruits could be used safely after 15 days from bifenazate spraying and after 3 days from spirodiclofen spraying. The concentration of abamectin after 21 days did not reach MRL. The half-life values (t1/2) of bifenazate, spirodiclofen, and abamectin in strawberry fruits were 0.99, 0.86, and 5.7 days, respectively.

The monitoring of the counterfeit situation of a pesticide widely used in Egypt (abamectin) was done through the present study as seven samples of Abamectin formulations were collected from the Egyptian market. Packaging and labels were checked and analyzed by HPLC to determine the active ingredient content present in these samples. GC-MS and FTIR were used for additional analysis and detection of other active ingredients in the formulation.Counterfeit pesticides were studied in Egypt by doing questionnaires for all workers in the pesticide system (farmer - trader - researchers in the pesticide field) and the results of these forms were analyzed to show the most dominant pesticides in Egypt, in addition to random purchase of pesticides from the Egyptian market and the most number of samples Is from (abamectin pesticide) (7 samples).To obtain this number of abamectin formulations, 58 different pesticide formulations (16 different active ingredients) were collected from the Egyptian markets, and the share of abamectin was 7 samples (one active substance), representing 12.1% of the total tested samples. The obtained results showed that Examination of Packaging and indicated that three samples were not registered through Egyptian Agricultural Pesticides Committee thus representing 42.86% of the total tested samples. The non-registered products are Komaktin Gold Plus, Super Vertimic and Abamectine Strela. Three samples have registration number as other formulations already registered in Ministry of Agriculture which are Abamectin Super, Farmactine and Abamectin power. The last product (Tinam) has the correct registration number (no.1391) and it is the same number used to register it in Ministry of agriculture. The percentage of the active ingredient in 5 samples was less than the acceptable limits, The samples were (Abamectin super, Komaktin Gold Plus, Abamectin Power, Super vertimic and Abamectine strela) active ingredient content was 1.416, 0.64, 1.01, 0.2 and 0.12% respectively. One sample (Farmactine) didn’t contain Abamectin, and the sample (Tinam) was within the acceptable limits (1.53%). GC-MS used to determine the presence of any other materials or active ingredients within the samples. The result showed that Abamectin Super sample contains (Lambda cyhalothrin at R.t. 29.512 min), Farmactine sample contains (Fenpropathrin at R.t. 28.634 min), Abamectin Power sample contains (Diazinon at R.t. 16.088 min and Cypermethrin at R.t. 26.554 min) and Super Vertimic sample contains (Fenpropathrin at R.t. 23.916 min and Lambda cyhalothrin at R.t. 34.85 min). Three products Komaktin Gold Plus, Tinam and Abamectine Strela didn’t contain other active ingredients.The physical properties of the studied samples before and after storage were determined through emulsion characteristic test and four samples (Abamectin super, Farmactine, Abamectin Power and Tinam) showed good emulsion characteristics before and after storage. Super vertimic and Abamectine strela samples showed poor emulsification characteristics before and after storage. Komaktin Gold Plus showed good emulsification before storage but poor emulsion characteristics after storage.

The dissipation behavior of three pesticides, bifenazate, spirodiclofen and abamectin was studied in strawberry fruits using a modified QuEChERS extraction technique. The residues of the tested acaricides were determined under field conditions after 1 hour (zero days), 1, 3, 7, 14, and 21 days. The maximum residue limits (MRLs) were 2, 2, and 0.15 mg/kg for bifenazate, spirodiclofen and abamectin, respectively. The strawberry fruits could be used safely after 15 days from bifenazate spraying and after 3 days from spirodiclofen spraying. The concentration of abamectin after 21 days did not reach MRL. The half-life values (t1/2) of bifenazate, spirodiclofen, and abamectin in strawberry fruits were 0.99, 0.86, and 5.7 days, respectively.

The toxic effect of Abamectin and Pyriproxyfen action on the 1st instar larvae of the pink bollworm, Pectinophora gossypiella (Saund.) was studied under laboratory conditions. The toxic action of the tested compounds at their estimated LC50 values on some biological aspects of the treated insect as well as total protein content and the activity of b-esterase in the affected larvae were also studied. Based on the obtained results, abamectin was more toxic than pyriproxyfen after 24, 48 and 72 hr of treatment. In addition, the effect of treatment with the LC50 value of both tested compounds on newly hatched larvae was extended to the following developmental stages, represented as some morphological deformities. Also, total protein content in treated larvae increased than their control when Pyriproxyfen was tested but decreased when Abamectin was administered to larval diet. The electrophoretic analysis using SDS-PAGE for β-esterase enzyme in the larval stage fed on diets treated with tested compounds showed clear variation in the dense and number of enzyme bands.

The toxicological effect of two pesticides, pyriproxyfen and abamectin were eva-luated on third instar larvae of the cotton leafworm, Spodoptera littoralis (Boisd.). According to the estimated toxicity values, i.e. LC50, LC90 and slope values, the chemical abamectin showed that it was slightly more toxic than pyriproxyfen. The effect of these two insecticides, at the determined LC50 and LC25 values on the di-gestive physiology of treated larvae, as indicated by some nutritional indices was conducted. Obtained results demonstrated that pyriproxyfen and abamectin caused a significance reduction in growth of treated larvae as depicted by larval weight gain Also, a significant decrease was found in the efficiency of ingested food to body matter and efficiency of conversion of digested food to body matter as compared to untreated insects. These effects were generally more evident when abemectin was used. The two tested compound also caused histological changes in the midgut of treated larvae, in form of disruption in the columnar epithelium cells and stretching leading to tearing in the peritrophic membrane. This observation might explain the impairment in nutritional indices in treated larvae as compared to the control.