A study was done on the feeding behaviour, development indices, and biochemical response of 4th instar larvae ofSpodoptera littoralisin which seven cotton genotypes were used: Giza86, Giza88, Giza92, 10229 × Giza 86, H10, Suvin, and Karshenseki. Castor bean leaves were used as the control. All the tested cotton genotypes decreased the feeding behavior ofS. littoralislarvae in terms of consumption percentages, consumption rate (CR), growth rates (GR), efficiency of conversion of ingested and digested food (ECI and ECD), approximate digestibility (AD), and feeding deterrence (FDI) compared to the control. Additionally, all the tested cotton varieties prolonged the time taken for larval and pupal duration and reduced both the pupation percentages and the weight of the resulting pupae, as compared to the control. Giza86 recorded the lowest values of both larval growth index and fitness (7.31 and 1.05, respectively) while the genotype Suvin recorded the lowest standardised growth index (0.020) more than other genotypes and the control that gave 10.16, 1.53, and 0.032, respectively. There was a significant inhibition in the level of both total soluble protein and total lipids, and activities of amylase and the trehalase enzymes in all the tested varieties, compared to that found in the control.

The carried out investigations evaluated ovicidal activity of mahlab, Prunus mahaleb L. kernel oil against cotton leafworm, Spodoptera littoralis (Boisd.). The chemical constituents of the fixed oil of mahlab were analyzed using gas-liquid chromatography (GLC). Timnodonic (33.07%), oleic (28.71%) and linoleic (24.35%) were the basic fatty acids, while the major hydrocarbon and sterol were found to be heneicosane (62.57%) and β-sitosterol (10.57%). The LC50 values for the one-day-old egg masses were found to be more susceptible than 3-day-old ones. Moreover, the leaf dip technique occurred to be more efficient than spraying technique. The results also showed abnormalities in the external morphology of egg shell, chorion surface, shell imprints and aeropyles of S. littoralis eggs treated with mahlab and KZ oils as compared to a control by using scanning electron microscope. Generally, the tested oils significantly reduced the activities of transaminase enzymes (AST and ALT), acid and alkaline phosphatases and total soluble protein except mahlab oil on acid phosphatase as compared to a control. Additionally, the oils of both mahlab and KZ oil affected some biological aspects such as incubation period, larval duration, larval mortality and pupal weight comparing to a control.

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The chemical constituents of the essential oil of lemongrass, Chymbopogon citratus that collected from Sharquia Governorate, Egypt, were determined by GC-MS analysis. Geranial and neral were the basic constituents in the essential oil that recorded (48.692 and 34.137%, respectively). Moreover, the acaricidal and repellent activity of the essential oil were evaluated against T. urticae under laboratory conditions. According to LC50 and LC90, the lemongrass oil was more toxic against adults of T. urticae using spraying method than leaf dip technique method (direct feeding). Moreover, all the tested concentrations of the essential oil significantly reduced hatchability percentages of T. urticae eggs than control, that recorded (85.33 ± 3.72, 77.33 ± 3.76, 57.33 ± 3.59 and 33.33 ± 3.01%) for (0.25, 0.50, 1.00 and 2.00 %, respectively). Control gave 96.00 ± 0.00%. Also, the higher used concentration of lemongrass oil, recorded the highest significant repellency percentages against adults of T. urticae (79.96 ± 3.44%). While the lower one gave the least significant decrease (46.32 ± 2.61%).

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Current research has focused on the inhibitory effects on the reproductive organs of cotton leafworm, Spodoptera littoralis resulting from 4 th instar larvae treated with sublethal concentration (LC 25) of methoxyfenozide. Results showed elongation in the immature stages and longevity of adults than control, as well as reduce pupal weight, oviposition period, fecundity and hatchability percentages. Anatomical structures of virgin moths surviving from larvae treated with LC 25 of methoxyfenozide showed general atrophy and abnormal features for ovaries and testes than that of untreated ones. Histological disruptions were recorded in ovaries in vitellogenesis and post vitellogensis stages as deformation in follicular shape, clumping of the chromatin material in nurse cells and disorganization of yolk and appearance of vacuoles between yolk and chorion. While in treated testes the testicular wall disappeared and vacuoles between follicles take place. Methoxyfenozide caused alterations in the amounts of both total soluble protein and total lipids and also in the activities of acid and alkaline phosphatases and phenol oxidase in the ovaries and testes of the resulted adults as compared to control adults.

Fourth instar of silkworm larvae, Bombyx mori L. were fed on mulberry leaves fortified with two different multivitamin sources, natural (bee honey) and synthetic (Pharovit iron). The impact of the larval, cocoon, shell and pupal weight, filament length and weight and the number of breaks during reeling (filament size) were examined. Different results on biological parameters were obtained based on used concentrations or treatments. All the tested concentrations of two multivitamins increased filament size than control except the least concentration of Pharovit iron. Results also established highly significant elevation in the total soluble protein and increased number of protein bands, while decreased significantly the activity of transaminase enzymes (AST and ALT) either in honey or Pharovit treatments comparing to control. Thus, fortification of mulberry leaves with honey enhance protein metabolism, consequently, improving the commercial qualities of filament size, that's very important in sericulture.

Background: Neonicotinoids have become the most widely used class of insecticides with a global market share of more than 25%. They are a class of neuroactive insecticides chemically related to nicotine. Thiamethoxam is a second generation neonicotinoid insecticide in the thianicotinyl subclass used worldwide that contains nitro group. Acetamiprid is a systemic insecticide, belonging to the chloronicotine subclass and having a broad insecticidal spectrum that contains cyano group. Aim: The present study aims to investigate: Toxic effects of some neonicotinoid insecticides (Thiamethoxam and Acetamiprid) and investigate also biochemical, hematological and histological alterations of these insecticides. Materials & Methods: Adult male Swiss albino rats were divided into 3 groups: 1st negative control group; 2nd Thiamethoxam group administrated 156 mg/Kg body weight every day along 30 days; 3rd Acetamiprid group administrated orally 100 mg/Kg body weight every day along 30 days. Blood, liver and kidney tissues samples were collected for some biochemical, hematological and histopathological studies. At the end of the experiment, animals were scarified every 10, 20 and 30 days. Results: Thiamethoxam and Acetamiprid induced alterations in liver function tests, kidney function tests and hematological parameters. As these changes were accompanied with hepatic necrosis as well as inflammation. Moreover, they induced cloudy swelling of renal tubules and renal inflammation. Conclusion: Our data suggested that, Thiamethoxam may be more hepatotoxic, nephrotoxic and produced hematological changes than Acetamiprid. Use of these insecticides should be limited.