الفهرس 
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Abstract
The cigarette beetle, Lasioderma serricorne (F.) is a serious economic insect pest of many stored products, spices and dried fruits. This work was carried out in the laboratory of Plant Protection Department, Faculty of Agriculture, Zagazig University, Egypt to study the effect of eight different botanical foods as insect diets [standard insect rearing diet (95% flour and 5% dry yeast), wheat germ, oat grains, cumin seeds, corn flakes, chamomile flowers, roselle flowers and fenugreek seeds] on some biological aspects of this insect, under non-choice and free-choice bioassays. Also, insect population growth after one and three months of storage as well as percentage of weight loss was investigated. The effect of the heavy insect infestation on certain chemical constituents of the tested foods as food moisture content, total carbohydrates, total proteins, ash, total fats and total fibers was determined and compared to control after three months of storage. Moreover, the contact and fumigant toxicity of five essential oils (clove, mint, orange, garlic and rosemary oils) to the adult stage of cigarette beetle was studied as a relative safety method to control of this insect pest. The obtained results revealed that the standard insect rearing diet and wheat germ were the best foods where the insect larval period was very short (17.90 and 18.09 days, respectively), while fenugreek seeds was least preferred food as larval diet (36.91 days). Pupal period ranged from 7.18 to 11.82 days on wheat germ and corn flakes, respectively. The shortest complete developmental period was 30.67 days on wheat germ and the longest one was 53.21 days on fenugreek seeds. Values of the susceptibility index ranged from 3.03 to 8.08% for fenugreek seeds and wheat germ, respectively. The standard insect rearing diet and wheat germ were the best foods since they produced the highest mean progeny number after one and three months of storage (204.33, 151.67 and 3151.30, 4313.30 adults, respectively). Mean weight loss percentages ranged from 0.53 to 5.33% on corn flakes and oat grains after one month of storage, respectively. However, it reached its maximum value (31.12%) on the standard insect rearing diet and minimum value on fenugreek seeds (1.03%) after three months of storage. The highest relative weight loss per each adult insect was 27.83% on chamomile flowers and the lowest one was 2.46% occurred on corn flakes after one month of storage. After three months of storage, the value increased on corn flakes, standard insect rearing diet, roselle flowers, fenugreek and cumin seeds, while decreased on the other tested food kinds. A positive correlation was found between heavy insect infestation on some different food kinds and their chemical constituents as moisture content, total proteins, total fibers, ash, total carbohydrates and total fats. In contrast a negative one was recorded on the other chemical constituents. Positive correlation coefficients with all tested chemical constituents on uninfested and infested foods were detected by highly significant for total carbohydrates and total proteins, while significant for total fats. The heavy insect infestation increased both the progeny number and the weight loss which affected the chemical constituents of the different tested food kinds compared to control. All tested food kinds were infested by the cigarette beetle L. serricorne and no immune food was found free from the insect infestation with preferable some tested food kinds to the insect. Moreover, the heavy insect infestation after three months affected the chemical constituents of the tested food kinds. Standard diet and wheat germ were the most attractive foods under free-choice bioassay, while fenugreek and cumin seeds appeared the least ones. The most preferred foods had the highest numbers of eggs and resulted progeny. In contrast, fenugreek and cumin seeds recorded the lowest ones. The results of surface contact toxicity after one day of exposure to the tested essential oils showed that clove oil was the most effective oil based on its lower LC50 value (0.77%) followed by rosemary, garlic and orange oils, while the mint oil was the least effective one due to its higher LC50 value (1.28%). After two days of exposure, rosemary and clove oils were the most effective oils based on its LC50 values (0.63 and 0.64%), respectively, while mint oil was the least effective one where its LC50 value was 1.06%. The fumigant activity studies of the of the tested oils showed that mint oil was the greatest effect on the L. serricorne adults, its LC50 value was 0.099µl/ml of air after two days of exposure, while rosemary oil had the least effective one with LC50 value of 2.141µl/ml of air. All tested oils as contact or fumigant agents showed variable activity against L. serricorne adults and can be used in integrated pest management. This part needs other complementary studies as investigating the combined effect of mixing the oils together or with the one of the recommended pesticides and bioassayed against the different insect stages.