Efficacy of essential oils as antiseptics on the productive characteristics of the mulberry silkworm Bombyx mori L.

The study aimed to test the efficacy of three essential oils (basil Ocimum basilicum L., lemon Citrus limon (L.) Osbeck, and thyme Thymus vulgaris L.) as disinfectants, including their positive and negative effects, on the biological and productive parameters of the silkworm Bombyx mori. Biological parameters: basil oil treatment at 2000 ppm the highest significant 5th instar larval weight and pupal weight were 2.226 g and 0.787 g. In addition, at the same concentration, recorded the lowest significant mortality percentage and 5th instar larval duration, were 0.787 g and 5.09% respectively. On the other hand, lemon and thyme oils at 4000 ppm come in the second place the same parameters, compared to the control and the chemical disinfectant. While it is equal to the concentration of 8000 ppm for the oils tested in all biological parameters with the control and chemical disinfectant. Economical parameters: basil oil at 2000 ppm and lemon and thyme oils at 4000 ppm had the highest significance for cocoon weights, cocoon shell weight, and silk productivity, which were 1.203 g, 0.220 g, 2.34 cg for basil oil, 1.139 g, 0.210 g, 2.367 cg for lemon oil and 1.265 g, 0.216 g, 2.397 cg for thyme oil, compared with control and disinfectant chemical groups (0.993 g, 0.157 g, 1.49 cg and 0.991 g, 0.160 g, 1.68 cg, respectively). The highest significant difference of cocoon percentages was seen with basil oil at 2000 ppm, compared to the other treatments. DOI: http://dx.doi.org/10.5281/zenodo.590659

The Binary Mixtures of Lambda-Cyhalothrin, Chlorfenapyr, and Abamectin, against the House Fly Larvae, Musca domestica L.

The house fly Musca domestica L. is one of the medical and veterinary pests that can develop resistance to different insecticides. Mixing insecticides is a new strategy for accelerating pest control; furthermore, it can overcome insect resistance to insecticides. This study aims to evaluate three insecticides, chlorfenapyr, abamectin, and lambda-cyhalothrin, individually and their binary mixtures against 2nd instar larvae of M. domestica laboratory strain. Chlorfenapyr exhibited the most toxic effect on larvae, followed by abamectin then the lambda-cyhalothrin. The half-lethal concentrations (LC50) values were 3.65, 30.6, and 94.89 ppm, respectively. These results revealed that the high potentiation effect was the mixture of abamectin/chlorfenapyr in all the mixing ratios. In contrast, the tested combination of lambda-cyhalothrin/abamectin showed an antagonism effect at all mixing ratios against house fly larvae. The total protein, esterases, glutathione-S-transferase (GST), and cytochrome P-450 activity were also measured in the current investigation in the larvae treated with chlorfenapyr. Our results indicate that GST may play a role in detoxifying chlorfenapyr in M. domestica larvae. The highest activity of glutathione-S-transferase was achieved in treated larvae with chlorfenapyr, and an increase in cytochrome P-450 activity in the larvae was observed post-treatment with Abamectin/chlorfenapyr