Objectives: The present study was prepared to investigate the impact of insect density, adult emergence of Tribolium castaneum on the secretion of Benzoquinones (BQs) consist of methyl-1,4-benzoquinone(MBQ) and Ethyl-1,4-Benzoquinone (EBQ), and accumulation of Aflatoxins (AFs) in wheat flour stored at different periods. Methods: Forty grams of wheat flour were put into small glass jars (8 cm diameter and 12 cm length). Then T. castaneum was put in each jars at rates of 10, 20 and 30 unsexed pairs of insect adult. The jars were covered with muslin cloth and the rubber band was fixed to prevent insects to escape. A glass jar without any insects served as the control. The jars lifted on bench in the laboratory for two, three and four months of storage under laboratory temperature conditions (with average 28 ± 20C and 65±5 R.H). The previous design was replicated three times. At the end of each storage period, the jars containing the flour were sieved thoroughly by 40 wire mesh size to separate the insects. The insects have been counted on the other hand wheat flour was prepared to determine MBQ, EBQ and AFs by HPLC methods. Results: The results indicated the levels of EBQ higher than MBQ in all infested samples at all insect densities (No. of insect pairs). The concentrations of MBQ in wheat flour released by ten adult pairs (10P) with the three storage periods two, three and four months were 10.42 ± 0.56, 22.38 ± 3.67, 27.06 ± 6.71µg/g, respectively. These results increased with insect densities to (30p) were 39.67 ± 0.10, 63.58 ± 2.35 and 106.24 ± 7.4 µg/g after storage periods two, three and four months, respectively. In addition to the concentrations of EBQ with (10P) were 67.45 ± 3.64, 98.0 ± 6.1 204.66 ± 5.8 µg/g with storage periods two, three and four months, respectively. In case (30P) the levels of EBQ were 376.7 ± 0.87, 570.1 ± 2.11 and 1558.66 ± 10.88 (µg/g). The highest concentration of the BQs 1664.90 ± 11.43 (µg/g) released by T. castaneum achieved with the highest adult emergence (1021 insect adult) and the highest insect density (30p) at four months storage period. In general, AFs levels enhanced with a period of storage and insect densities. Conclusion: Levels of the BQs (MBQ and EBQ) increased with an increase of storage periods and insect densities. Therefore, the presence of this insect should be prevented in stored wheat flour reducing AFs contamination is possible by storage for short time and prohibit insects which causes an increase temperature of the flour and moisture, all of which promote production of AFs.

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Carbohydrates, lipids and proteins contents were evaluated in 5 th larval instar haemolymph of Spodoptera littoralis (Boisd.) that treated with four isolates of entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Paecilomyces lilacinus and Lecanicillium antillanum at 1 st , 2 nd , 3 rd and 4 th days. Generally, data in present work cleared that, there was significant decrease in haemolymph carbohydrates of larvae injected with the entomopathogenic fungi in the three time intervals (1 st , 2 nd and 3 rd) under investigation compared to control. The concentration level of protein content of larvae injected with the fungi significantly increased as compared with control insects in (1 st) day, then there is no significant change in the content after 2 nd and 3 rd day except increasing was noticed with the two fungi (B. bassiana and L. antillanum).There were significant increases of carbohydrates and protein contents observed in the last day (4 th day) due to effect of fungal infection. Significant increases of lipid content was noticed in the 5 th instar cotton leaf worm larvae inoculated with the four tested fungi from 1 st to 4 th day. The overall results indicated that total S. littoralis larvae proteins, carbohydrates and lipids contents vary significantly during infection of the tested fungi at the four time intervals (1 st , 2 nd 3 rd and4 th days) and this tend to dramatically changes in the composition of haemolymph, thus abnormal growth and development of insect caused.

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Experiments were conducted to estimate the susceptibility of two apple cultivars (Anna and Golden dorset) to infestation with Panonychus ulmi Koch (Acari: Tetranychidae) and its population fluctuation during the two successive seasons, 2012 and 2013 at Menoufia governorate. The results showed that, Anna cultivar was the most highly susceptible recording average of 7.34 and 10.5 mite moving stages/leaf during the two successive seasons, respectively. The lower infestation was recorded with Golden dorset cultivar, being 1.6 & 7.49 mite moving stages/leaf during the two successive seasons, respectively. Susceptibility of apple cultivars to infestation with P. ulmi may be affected by plant leaf morphological structure and its chemical contents. The density of trichomes of Golden dorset cultivar was higher than that of Anna cultivar, the less density of trichomes the more mite infestation. Also, when the level of total phenolic compounds increased the infestation percentage decreased, while no effect of Tannins occurred. Mite populations reached its peak during May and April in the first and second seasons, respectively, and infestation was lower in the first season.

The selected four tomato cultivars {(Alissa F1, Super strain B, G.S 12 F1and Logain (E603 F1)} differed in their susceptibilities to the tomato borer, Tuta absoluta in the two studied successive years (2013 and 2014). Seasonal abundance of this pest was higher in early summer and summer plantations of year 2013 than that recorded in year 2014. The highest seasonal mean number was recorded on Alissa cultivar for both studied years followed by Super strain cultivar then G.S. cultivar. While the lowest mean number was achieved with Logain cultivar. The essential oil analysis by GC/MS of four tomato cultivars leaves revealed the presence of 33 peaks. A total of 33 components of the essential oil were identified. Aliphatic hydrocarbons terpenes compounds were found to be the most abundant volatiles in the four tomato cultivars except G.S. cultivar. The analyses revealed that the major identified aliphatic hydrocarbon components in the leaves oil of Logain and Alissa tomato cvs. (The lowest and the highest infestation with T. absoluta) were Octacosane, Hexacosane, Triacontane, Heptacosane, Nonacosane, Tetratriacontane, Hexatriacontane and Tetracosane. Susceptibility interpretation of Logain and Alissa tomato cvs. to T. absoluta may be attributed to the presence of high contents of the toxic and repellent hydrocarbons octacosane and hexacosane in Logain tomato cv. and high content of the attractant hydrocarbon tetracosane in Alissa cv. From these results it can be recommend to use the tolerable Logain tomato cultivar in breeding programs and also, preparing a commercial product/formulation from hydrocarbons octacosane and hexacosane to be used as repellent and tetracosane as a trap to T. absoluta.

fficacy of three acaricides (Ortus 5% EC, Milbeknock 1% EC and Cascade 10% DC) and predatory insect; Chrysoperla carnea Stephens was evaluated on the European red mite Panonychus ulmi Koch (Acari: Tetranychidae) movable stages infested apple orchards during the two successive seasons; 2012 and 2013 at Darawa village, Ashmon, Menoufia governorate, as well as determining the biochemical changes in the treated insects. The results show that, The highest reduction percentages of P. ulmi movable stages during 2012 and 2013 seasons were recorded with Ortus followed by Milbecknok then the predatory insect; C. carnea, while the lowest reduction percentages were recorded with Cascade. The effect of the two acaricides Ortus and Milbecknok (the highest toxic acaricides) on the major biochemical components of P. ulmi adult females showed that, the acaricide Ortus achieved high effects on the total lipids content and the two enzymes Acetylcholinesterase (AchE) and Glutathione-S-transferase (GST). The acaricide Milbecknok recorded high effects on the total lipids and carbohydrates contents and lipase, trehalase, amylase, AchE and GST enzymes. The two acaricides Ortus and Milbecknok are effective in controlling European red mite on apple trees and this can be attributed to abnormal changes of the major biochemical components in the treated mites. The predatory insect; C. carnea has efficient predation against P. ulmi and resulting increasing in the reduction of mite populations.

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