الفهرس 
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Abstract
”Efficacy of Some Insecticides against Cotton Mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) I. Toxicological studies on the cotton mealybug Phenacoccus solenopsis Tinsley: 1- Susceptibility of the 3rd instar nymph of CMB after one and three days after synthetic compounds application Results showed that Profenofos exhibited a high degree of efficiency as insecticide after one day of initial application followed by Lambda-cyhalothrin, Malathion, Flufenoxuron and Hexaflumuron . However Lambda-cyhalothrin proved a high degree of efficiency as insecticides after three days of application followed by Profenofos, Hexaflumuron, Flufenoxuron and Malathion. 2- Susceptibility of the 3rd instar nymph of CMB after three and seven days after oils and plant extracts application Data showed that Rosemary exhibited a high degree of efficiency as insecticide after three days of initial application followed by Lemon grass, Camphor, Olibanum, House pine and Diver® oil. However Lemon grass proved a high degree of efficiency as insecticides after seven days of application followed by Rosemary, Olibanum, Diver® oil, Camphor and House pine. II. Gas chromatography-Mass Spectrometer/ analysis of essential oils: The qualitative and quantitative compositions of the essential oils were analyzed and the most abundant constituents of E. melliodora were found to be (z)-tagetenone (20.56%), p-cymene (16.62%) and (-)-spathulenol (14.60%). The S. rosmarinus essential oil mainly consisted of 1,8-cineol (18.37%), (-)-spathulenol (5.79%), and (+)-limonen (3.17%), while the major constituents of C. citratus essential oil were ɤ-citral (70.44%) and γ-dodecalactone (9.22%). S. rosmarinus and C. citratus essential oil showed a significant relative percentage of monoterpenes (90.87% and 89.06%), respectively than E. melliodora (77.2%), indicating that their presence and percentages may responsible for the highly insecticidal properties against P.solenopsis 3rd instar nymph. III. Biochemical studies: 1- Determination of transaminases activity GPT (ALT) and GOT (AST) Data indicated that all tested compounds caused fluctuation in GPT and GOT activities during experimental periods. Lambda-cyhalothrin (pyrethroid insecticide) caused a significant decrease in GPT enzyme activity then changed to significant increase in enzyme activity to reach (135.32 %) 5th day post treatment. While a significant increase was obvious in GOT enzyme activity with no significant changes found in the 3rd day post treatment. Lemon grass Cymbopogon citratus essential oil caused a significant increase in GPT enzyme activity 1st day after treatment with no significant changes found in the 3rd and 5th day post treatment. While a significant increase was obvious in GOT enzyme activity in 1st, 3rd and 5th day post treatment. Olibanum Boswellia carterii natural unorganized drug caused a significant increase in GPT and GOT enzymes activity in 1st, 3rd and 5th day post treatment, while a significant increase appeared on the GPT enzyme activity in the 5th day post treatment. The miniral oil, Diver® caused a significant decrease in GPT and GOT enzymes activity in the 1st and 3rd day after treatment. 2- Determination of Alkaline phosphatase (ALP) activity Data demonstrated the effect of the LC50’s of the tested compounds on ALP activity of the 3rd instar nymph of P. solenopsis to confirm their insecticidal potency. All treatments exhibited significant inhibition of ALP activity along the experimental period except in case of lemon grass after one day from treatment. The Diver® miniral oil caused the greatest inhibition of ALP activity followed by Lambda-cyhalothrin then, Lemon grass EO and Olibanum natural unorganized drug below the control level in the 5th day post treatment. IV. Biological studies: Developmental durations after treatment with the LC50 of the synthetic compounds Egg incubation period Data about the control experiment showed that there is no difference from control. Immature stages Data showed that the LC50 of Lambda-cyhalothrin caused an increase in the duration of newly hatched nymph’s first instar (crawlers). Decrease appearance in the third nymphal instar duration compared to control. After using the LC50 of Diver® oil with young adult females an increase observed with the durations of crawlers and second nymphal instars but a highly decrease was found in the third nymphal instar duration compared to control. Mature female stage: Data showed that when treated with LC50 of Lambda-cyhalothrin the pre-oviposition and oviposition periods of P. solenopsis increased. While, a high decrease appeared with the post-oviposition period . Total life cycle highly decreased . Data reported that the number of eggs laid by a single female (fecundity) during its entire life period increased. Results showed that when treated with LC50 of Diver® oil pre-oviposition and oviposition periods of P. solenopsis increased . While, a high decrease appeared with the post-oviposition period . Total life cycle highly decreased . Data reported that fecundity during its entire life period highly increased compared to control. 2. Developmental durations after treatment with the LC50 of the phytochemical compounds Egg incubation period Data indicated that there is no difference from control. Immature stages Data showed that the LC50 of Lemon grass caused an increase in the duration of crawlers; it lasted for 17 days. The second nymphal instar duration was 11 days. Highly decrease appearance in the third nymphal instar duration compared to control. After using the LC50 of Olibanum with young adult females a decrease observed with the duration of crawlers and also the second nymphal instar duration increasedbut the a highly decrease was found in the third nymphal instar duration compared to control. Mature female stage: Data showed that no differences happened in the pre-oviposition and oviposition periods of P. solenopsis when treated with the LC50 of Lemon grass. While, a highly decrease appeared on the post-oviposition period. A highly decrease in female longevity and total life cycle happened compared to control. Results showed a decrease on pre-oviposition, oviposition and post-oviposition periods of P. solenopsis when treated with LC50 of Olibanum. A highly decrease is obvious in female longevity and total life cycle compared to control. Data reported that fecundity decreased compared to control. Number of females of P. solenopsis Tinsley laying eggs after treatment with the tested compounds Our results revealed that the number of females of P. solenopsis laying eggs after treatment was not affected when treated with the studied synthetic compounds, but we found a highly significant decrease when treated with the Lemon grass essential oil (N=1) followed by Olibanum the natural unorganized drug (N=4), compared to control, consequently, a decrease in the pest population and a decrease in the rate of infestation of preferred economic field crops.