A crude acetone extract and oil of ripe fruits from Melia azedarach L. were evaluated against the 2 nd and 4 th instar larvae of Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae). Both oil and extract exhibited highly signifi cant growth inhibition at all concentrations tested, while the oil of M. azedarach recorded higher insecticidal activity against both instars than the crude extract. GC-MS analysis of the oil revealed the presence of linoleic acid methyl ester, oleic acid methyl ester, and free oleic acid as the main components in addition to hexadecanol, palmitic acid, methyl esters of stearic acid and myristic acid. Fatty acids and their esters were not only the main constituents of essential oil from the ripe fruits of M. azedarach, but also mainly responsible for the insecticidal and growth inhibition activity against S. littoralis.

Powdery mildew disease, caused by Erysiphe cichoracearum, is considered one of the most severe pathogenic threats of sunflower worldwide. This study discusses how to improve the effect of biocontrol agents, as a more economic and ecofriendlier alternative to fungicides, by mixing different bioagents (Trichoderma harzianum and Bacillus subtilis) with different antioxidants (ascorbic acid and salicylic acid), either individually or combined. They were applied to sunflower during two successive seasons to determine their effectiveness in promoting growth and inducing resistance in sunflower against powdery mildew disease under field conditions. Results show that all treatments reduced the severity of powdery mildew disease significantly compared with control. A synergistic effect was noticed when combining T. harzianum and salicylic acid led to a significant decrease in powdery mildew disease severity in sunflower in comparison to control. In general, the results suggested that the integration of antioxidants with bioagents showed a better response to control powdery mildew disease than single treatments. Applied treatments in the field significantly increased all of the studied growth parameters, plant length, fresh and dry weight. All treatments showed a remarkable increase in physiological aspects (enzymes activity and total phenol content).

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Toxicity and reduction in larval body weight studies were performed to determine the activity of linoleic acid against the 2 nd and 4 th instar larvae of Spodoptera littoralis. The tested fatty acid showed high significant toxic effect on the two instars, with LC 50 values of 4.78 and 9.11 g/100 mL, respectively. Linoleic acid resulted in significant larval weight reduction. The percentage of larval body weight reduction against the 4 th instar was higher than that of the 2 nd instar larvae.

Herein, we declare on the biosynthesis of synthesised silver nanoparticles utilizing the aqueous extract of Origanum Marjorana by reducing 1 mM silver nitrate at room temperature. AgNPs were characterized by using some common techniques such as an ultra violet spectrophotometer, Fourier transforms infrared spectroscopy, X-ray diffraction, and transmission electron microscopy. Morphologically, AgNPs demonstrated a spherical shape with an average particle size distribution of 63-85 nm. FT-IR studies showed the presence of bioactive useful bunches such as phenolic compounds, amines, and aromatic rings are found to be the capping, stabilizing specialists and required for the reduction of silver ions of AgNPs. The measurement of toxicity of AgNPs and the plant extract of O. marjorana against Earias insulana was also discussed. After the treatment of synthesized nanoparticles for two successive seasons, general reduction percentages on the infestation of the green boll caused by E. insulana larvae in the second season was more by 60.4% than the first season which was 44.73%. Synthesized AgNPs treatment was considered more effective than plant extract for controlling E. insulana. General reduction percentages in the infestation of the green boll caused by E. insulana larvae in the first season associated with the treatments with AgNPs and plant extract were 44.73 and 37.53% while the second season record 60.4 and 51.82%; respectively.

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Peanuts (Arachis hypogaea L.) represent one of the most vulnerable crops to infection by Aspergillus flavus under storage conditions. Accordingly, peanuts represent a major source of aflatoxin. The mycelial growth diameter of A. flavus was dramatically reduced by all tested plant extracts and their various concentrations as compared to the control. Thyme extract was the most effective in reducing the linear growth and the total aflatoxin production of A. flavus in vitro. Application of plant extracts on peanuts before the artificial infection with A. flavus under storage conditions showed high efficiency of reducing total aflatoxin production compared to the control. Thyme extract at concentration 5% was the most effective treatment in reducing total aflatoxin production. According to the protein electrophoresis results of A. flavus treated with rosemary, thyme, and basil plant extracts, thyme treatment caused the development of newly produced proteins with about 25 kDa molecular weights. Whereas in A. flavus isolate treated with rosemary, two bands with molecular weights of 63 and 75 kDa, respectively, entirely were vanished. Similarly, A. flavus isolate treated with basil resulted in disappearance of one band with molecular weight of 63 kDa.

oxicological, biological and histological effects of the isolated entomopathogenic fungus Metarhizium anisopliae from the red palm weevil adult on the newly molted 2 nd and 4 th instar larvae of the Egyptian cotton leaf worm, Spodoptera littoralis (Boisd.), were investigated under laboratory conditions at 27º ± 2º and 60% ± 5% R.H. Results revealed a decrease in the mean larval, pupal, and adult durations for the 2 nd and 4 th instar larvae surviving treatment with the LC 50 of 2.8x10 8 and 2.8x10 9 spore/ml for the two tested instar larvae, respectively. Treatment also caused a reduction in the pupation and adult emergence percentage. There was also a great reduction in the mean number of eggs/female and the mean number of hatched eggs; The histological changes in the mid gut tissues in 6 th instar surviving treatment with LC 50 of M. anisopliae as newly ecdysed 3 rd instar larvae was investigated. Sections in mid gut of untreated S. littoralis showed linning with columnar cells surrounded by cross longitudinal muscles fiber, the epithelial cells linning mid gut with its brush border and goblet cells. While, in mid gut of treated S. littoralis some epithelial cells which linning mid gut have lost their brush border, others were completely destructed.