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Showing 2 results for Kandil
Life-stage-Dependent Secondary Responses of Some Biorational Insecticides on Trichogramma dendrolimi (Matsumura) (Hymenoptera: Trichogrammatidae)

Volume 0, Issue 0 (ARTICLES IN PRESS 2024)
Abstract
In the study, lethal and sub-lethal doses of Neem Azal (azadirachtin 10 g/l), Nimiks (azadirachtin 40 g/l), Nimbecidine (azadirachtin 0.3 g/l), Oread (spinosad 480 g/l), and Nostalgist BL (1.5% Beauveria bassiana strain Bb-1-) were tested on different developmental stages of the egg parasitoid, Trichogramma dendrolimi  under laboratory conditions. The lowest melanized egg were found on the larval stage of parasitoid in the 200 ml dose of Nimiks (79.17%), on 5 ml dose of Oread (75.25 %) and on 250 ml dose of Nimbecidine (79.37 %). An approximately 10-fold decrease in emergence rates was determined in the larval, prepupal and pupal stages of the parasitoid at doses of 5 ml and 6.25 ml of Oread.  The other doses of the same insecticides resulted in 100% of mortality. The longest development time of T. dendrolimi was found on Oread with 6.25 ml (11.00 days), on Nimiks with 200 ml (11.04 days), and on Oread with 5 ml (10.90 days). No significant difference was observed in the sex ratio. The longevity of T. denrolimi was shorter than that of the control for all insecticides and doses applied to the larval, prepupal and pupal stages of the parasitoid. Parasitism rates of F1 and F2 varied greatly depending on the insecticides, doses and biological stage of the parasitoid. The new crop protection strategies aim to reduce the use of chemical insecticides while supporting the combined use of biorational insecticides and natural enemies. The study offers helpful data for IPM that is focused on the ecology.  
 
Toxicity of Insecticides against Tomato Leaf Miner, Tuta absoluta, and Its Predators and Determination of Their Residue Dissipation in Tomato Fruits

Volume 25, Issue 5 (9-2023)
Abstract
 Tomatoes are an important vegetable crop in different parts of the world, where they are grown year-round. Currently, the most important problem facing tomato growers in the world is the devastating damage caused by the invasive tomato leaf miner, Tuta absoluta Meyrick (Gelechiidae: Lepidoptera). In this study, the efficacy of three bioinsecticides (Bacillus thuringiensis formulations, spinosad and emamectin benzoate, and two chemical insecticides (indoxacarb and chlorpyrifos) against T. absoluta and their adverse effects on predators were conducted in two different governorates in Egypt, based on recommended doses of the tested insecticides. In addition, the residue dissipation of the tested insecticides was determined in tomato fruits. Results indicated that emamectin benzoate was the most effective insecticide, exhibiting the highest reduction in T. absoluta density of 78.05 and 87.11% in Giza and Qualybia governorates, respectively, followed by indoxacarb (77.01%) in Giza and spinosad (80.44%) in Qualybia. In addition, our finding proved that the tested biopesticide formulations, especially Bt formulations, are environmentally friendly to two of the most important predators in tomato cultivation: Nesidiocoris tenuis and Macrolophus pygmaeus Reuter. Moreover, the analysis of insecticide residues on tomato fruits revealed that bioinsecticide residues dissipated faster than conventional insecticide (chlorpyrifos). The results of this research suggested that bioinsecticides could be used for the management of T. absoluta under field conditions.
 
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