Effect of certain pesticides and their alternatives on the two-spotted spider mite Tetranychus urticae Koch on tomato crop under laboratory and greenhouse conditions

The purpose of this study was to determine the toxicity of fenpyroximate, bifenazate, emamectin benzoate, buprofezin, sulfur, K. Z oil, and chili nanosilver (AgNPs) extract against the two-spotted spider mite ( Tetranychus urticae ) associated with tomato plants ( Lycopersicum esculentum ) during the summer cultivations of 2017/2018 and 2018/2019 seasons, The bioassay revealed that the tested pesticides were in the same order of efficacy at both the LC50 and LC90 levels. The pesticides that were tested could be sorted in the following order: fenpyroximate ˃ bifenazate ˃ emamectin benzoate ˃ buprofezin ˃ sulfur ˃ K. Z oil ˃ chili AgNPs extract. The corresponding LC50 values were 90.02, 112.18, 131.96, 154.60, 220.14, 269.48 and 314.44 ppm, while the LC90 values were 4403.98, 742.45, 756.11, 1293.59, 914.76, 1568.16 and 1500.05ppm, respectively. On the other hand, χ2 values were 2.09, 1.68, 2.65, 2.96, 2.75, 5.20, and 5.24 respectively. The field experiments show that fenpyroximate, bifenazate, emamectin benzoate, buprofezin, sulfur, K. Z oil, and chili AgNPs succeeded in controlling T. urticae , where the means of reduction percentages of infestation were 76.91, 67.00, 71.64, 55.54, 69.40, 64.96 and 72.23 % in 2017/2018 season, respectively. While the means of reduction percentages of infestation were 83.55, 80.55, 78.62, 77.30, 78.29, 73.20, and 72.37 % in the 2018/2019 season, respectively.