الفهرس 
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Abstract
Peanut (Arachis hypogaea L) is an important oil and food crop. In storage, it is infested by several insect pests, such as the Almond moth, E. cautella, and the Red flour beetle, T. castaneum, which are the most important peanut insects; and the need for efficient control methods is important. The use of natural pest control agents especially those derived from host plants, may offer good promise in grain storage. Plant semiochemicals manipulate insect behaviour as safe control methods. Therefore, the present study aims to develop lures from semiochemicals as food odours for trapping both sexes of E. cautella and T. castaneum; and that can be integrated with other methods of control.
The following topics were studied and the obtained results could be summarized as follows: 1. Biological effects of different food sources on insect development:
The biological parameters (larval and pupal durations, pupal weight, percentage of emerged adults, their fecundity and sex ratio) of E. cautella were studied when fed on different host plants (date, peanut and whole wheat flour). The most preferred food was date which significantly gave the shortest larval and pupal durations, the highest pupal weight, the lowest larval and pupal mortality, the highest fecundity and egg hatchability. It was followed by whole wheat flour and peanut. The sex ratio was almost the same on the tested foods. Results of the above mentioned biological parameters also significantly showed that whole wheat flour was the most favorable food for T. castaneum, followed by peanut and then date. The sex ratio biased towards males on whole wheat flour, towards females on date and almost similar in case of peanut.
2. Oviposition preference (multi-choice test):The oviposition preference of E. cautella females was studied in multi-choice test by using date, peanut seeds, peanut shells, wheat flour and bran. Females strongly preferred date for egg laying followed by wheat flour then peanut seeds which had moderate attractive effect. Neither peanut shells nor bran induced oviposition by E. cautella females. The oviposition preference in case of T. castaneum female beetles showed that the mean number of deposited eggs was significantly higher in the wheat flour, wheat bran and then peanut seeds. Neither date nor peanut shells induced oviposition behaviour of female beetles.3. Behavioural response of tested insects towards food odours in olfactometer: In olfactometric analysis, the most favorite food odour for both male and female moths was date (48 and 64%), followed by wheat flour (36 and 50%) and peanut seeds (34 and 46%) attractant activity, respectively. The odds ratio of females was higher in all cases than those of males Concerning T. castaneum, wheat flour was strongly attractive to males, females and mixed sexes of beetles showing 67, 69 and 67% attractant activity, respectively; followed by wheat bran (45, 49 and 47%) peanut seeds (44, 42 and 41%) attractant activity, respectively, in olfactometric analysis. Peanut shells had the least attractive food odour (12, 13 and14%, respectively). In most cases, the odds ratio of females was higher than in males or mixed sexes.
4. Behavioural response of tested insects towards extracted food odours in olfactometer: The most attractive extracted food odour to E. cautella male and mated female moths was that of date (34 and 58%, respectively) at 0.1 ml concentration; where, the odds ratio of females recorded three times more than males. On the other hand, extracted wheat flour odour had moderate attractant activity recording 30 and 44% attractant activity, respectively, at the same concentration. Peanut seeds extracted odour had also moderate attractant activity towards both males and females (24 and 38%, respectively) at 0.02 ml concentration. This was followed by extracted wheat bran odour, then extracted peanut shells odour which showed no significant attraction than control at all tested concentrations. As to T. castaneum, extracted wheat flour odour showed the highest attractant activity for males, females and mixed sex beetles (61, 64 and 60%, respectively) at 0.1 ml concentration. It was followed by extracted wheat bran odour, recording 47, 49 and 46% attractant activity, respectively, at the same concentration. It was followed by peanut extracted odour, showing 32, 39 and 36% attractivity, respectively, at 0.02 ml concentration. Extracted date odour came next with different attractant activity at different concentrations, although following the same trend as above, that females were the most attracted sex. On the other hand, different concentrations of peanut shells extract gave weak attractant activity to the three tested groups of beetles. However, in all cases, the odds ratio of females was higher than that of males or mixed sexes.
5. Identification of main constituents of extracted most attractive food odours The relative percentage, molecular weight and chemical structure of the main constituents of date and wheat flour odours were carried out by using GC-MS analysis.The identified compounds of date odour extract accounted 94.83 % of the total constituents. The major compounds were identified as oleic acid followed by butylated hydroxytoluene and linoliec acid. They accounted 76.46%; while the other identified compounds accounted about 18.37 % only. Therefore, pure authentic sample from the fatty acid (oleic acid) was subjected for biological activity study as moths attractant. The identified compounds of wheat flour odour extract, on the other hand, represented 86.69 % of the total constituents. The first major compound was identified as palmitic acid followed by stearic acid and naphthalene. These three compounds formed 81.08 %; while the other eight identified compounds recorded 5.61 % only. Therefore, pure authentic sample from the fatty acid (stearic acid) was subjected for biological activity as beetles attractant.
6. Evaluation of date and wheat odours and their active compounds as lures in traps: The obtained results indicated that both sexes of E. cautella moth could be attracted and captured in the white sticky traps baited with extracted date odour. Bating traps with oleic acid (an active component of date) also captured both sexes of the moth, but in much less numbers. In both cases, females were highly more attracted to baited traps than to control ones. In case of T. castaneum, also more beetles were attracted and caught in the sticky traps baited with wheat flour odour than in traps baited with stearic acid (an active component of wheat flour). Both were more highly attractive than control. Bait concentration also appeared important in traps efficiency.
Finally, traps baited with semiochemicals or food odours can be used for catching both sexes of the insect pests; and can successfully and safely integrated with other insect control measures in IPM programs.