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.