Nine scale insect species (Hemiptera: Coccoidea) belongs to four families were collected during updated survey at Qaliobiya Governorate for two successive years. A key with photographs and illustrations are introduced; the seasonal fluctuation and the population density of all stages of the most serious soft scale insect, Pulvinaria psidii Maskell (Hemiptera: Coccidae) were studied in relation to five main weather factors. Three predators, Rodalia cardinalis Mulsant, Chilocorus bipustulatus L. (Coleoptera: Coccinellidae) and Amblyserius swiriskii (Athias-Henriot) (Acari: Phytoseiidae) were collected associated with P. psidii and their effect with the other meteorological factors are analyzed statistically using partial regression method to decide their contemporary effect. The half monthly variation was calculated and the number of generations of this soft scale per year were estimated throughout the two successive years of investigation to indicate the high infestation of this pest to reach 327 insect/ leaf at 1 st may, the lowest population density were during winter season. The efficacy of the alternative pesticides (Biological insecticides, mineral oils, IGRs) and organophosphorus insecticides for controlling this serious pest different stages during summer and winter field sprayings were applied to insure that: the summer spray was more effective than the winter spray, the mineral oils and soap gave high efficacy after two weeks of spraying and still increasing till the end of the experiment, without observed phytotoxicity; IGRs and biological insecticides started to give good efficacy after one month of spraying and also still to increase till the end, in addition to their safety effect, opposite to the synthetic insecticides that gave a very good efficacy at the beginning of the experiment and decreased gradually. Finely the application time is very important; the organophosphorus compounds must be replaced by these other friendly alternatives; rearing and releasing these predators must be used in this pest control management.

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The effect of a chitin synthesis inhibitor (Lufenuron) on the antennal segements and their sensilla of cowpea beetle, Callosobruchus maculatus (Fabricius) was studied by using scanning electron microscope.Seven types of sensilla were recognized on both untreated and treated antennae with 9 ppm of lufenuron, including Böhm bristles (BB), two types of sensilla trichodea (ST 1 , ST 2 ), sensilla chaetica (SC), two types of sensilla basiconica (SB 1 , SB 2 ) and grooved peg (GP). The functions of these sensilla were discussed in relation to their position on the antenna.Significant difference in lengths of most segments of the antennae between untreated and treated beetles was observed. A significant difference in lengths and diameters of nearly all types of sensilla was recorded. The highest increase in length of sensilla was noticed for the sensilla chaetica followed by sensilla trichodea. These types are used by insects as mechanosensory, sex pheromone and gustatory receptors that help them to make a decision to select their food and oviposition sites.

The present study was conducted to evaluate the neurotoxic effect of spinetoram on Spodoptera littoralis (Boisd.) larvae. Testing different concentrations of this green chemical compound against 4 th instar larvae showed that spinetoram is a fairly toxic with LC 50 (1.11 ppm). Its neurotoxicity was manifested as evident histopathological changes in the structure of neurosecretory (NSCs) and ordinary nerve cells (NCs) of suboesophageal ganglion (SOG) of this pest after treatment with LC 50 of this compound.Photo and electron micrographs of suboesophageal ganglion (SOG) of treated S.littoralis larvae with LC 50 of spinetoram showed aggregation of neurosecretory granules in the oval, triangle and irregular shaped neurosecretory cells but not in the round shaped cells. Also, the SOG of treated larvae showed an apparent vacuolization and increase in the size of cytoplasm, abundance and aggregation of mitochondria in nerve cells and all kinds of NSCs (round, irregular, triangle and oval) and the appearance of multivesicular bodies in the cytoplasm of neurosecretory cells.

The ultrastructure changes in the ovarian follicle of normal adult females and those developed from treated 5 th nymphal instar of Schistocerca gregaria with LC 50 of anti-chitin compound (cascade), plant extract (Oriza sativa bran extract) and synthetic pyrethroid (Karate) were examined. In the present study electron micrographs of follicle cells of treated adult females with previous compounds showed a degeneration of ovarioles and oocytes .There is also evidence of mitochondrial disintegration. It is also noticed that vacuoles were increased and enlarged in follicle cells and yolk bodies were cracked mostly in two halves.

The present data showed that the activities of all the tested enzymes except acetylcholinesterase (α,β-esterases, acid phosphatase and glutathione S-transeferase) were significantly higher in the whole body homogenates of the virgin queens ant, Camponotus maculatus (Fabricius) than that recorded for the workers. Also, the concentration of total soluble proteins of the virgin queens was higher than of workers. These proteins were electrophoretically separated into 22 bands (258.6 to 35.4KDa) in the virgin queen samples while they were separated into 19 bands (216.7 to 35.4KDa) in the worker samples. Ten protein bands were common between the two castes (108.1, 103.9, 99.8, 94.6, 63.7, 61.3, 55.9, 48.1, 40.6 and 35.4KDa) and the remaining bands were characteristic for each caste .Finally, there was difference in the genomic DNA of the two studied castes.

Repeated exposure to insecticides, particularly pyrethroids and organophosphates, has resulted in the development of insecticide resistance in the mosquito Culex pipiens, a primary disease vector. Glutathione S-transferase (GST) is involved in the phase II detoxification of numerous xenobiotics, including insecticides. In this study, a GST gene (CPIJ002678) was amplified, sequenced, and used in comprehensive molecular analyses ending up in development of a rapid assay to distinguish more tolerant individuals from susceptible Culex pipiens using the Restriction Fragment Length Polymorphism (RFLP) technique. Field collected Culex pipiens strains from untreated areas, organophosphates-treated areas and a lab strain reared for many generations, all were used in CDC bottle bioassays to evaluate the susceptibility status of the studied individuals to malathion insecticide. Interestingly, both field sites collected groups showed high levels of resistance at the malathion diagnostic time. Gene amplification, and bidirectional direct sequencing results were analyzed. Compared with the reference genome sequence, the pairwise alignment of the amplified sequences showed 96.6% similarity to the reference sequence in the GenBank database. The confirmed gene sequences were assembled and aligned using various bioinformatic softwares. The assembled contigs were used in NEBcutter V2.0 for constructing restriction maps and checked for the availability of differences (if present) between susceptible and more tolerant strains. Specific molecular RFLP markers were successfully recognized to differentiate the more tolerant from the susceptible Culex pipiens phenotypes.

The insecticide malathion (57% E.C.) was applied at the rate of 712.5 gm active ingredient per feddan on dill, Anethum graveolens L. and coriander, Corianderum sativum L. for controlling aphids infesting these plants. An analytical method, using gas chromatography equipped with flame photometric detector was used for detecting the insecticide residues. A field trial was conducted to determine the rate of dissipation of malathion in dill and coriander plants and in the resulting oil. Residue analysis showed that the initial deposits determined one hour after application were 35.81 & 22.7 ppm in dill and coriander plants, respectively. Rates of dissipation of malathion were 4.