POPULATION DYNAMICS OF CHAFF SCALE, PARLATORIA PERGANDII COMSTOCK IN COMPARATIVE ANALYSIS OF FLUCTUATING POPULATION DENSITIES ON THREE CITRUS VARIETIES IN EL-BEHEIRA GOVERNORATE, EGYPT.

Investigation throughout the subsequent years of 2011-2012 and 2012-2013 indicated that chaff scale, P. pegandii is an important economic pest on citrus trees in Abou El-Matamer area, El-Beheira Governorate, Egypt. It has been recorded in relatively high rates all over the year on three citrus varieties called Succari, Baladi and Navel oranges. Field observation and recorded data revealed that the common abundance was recorded for chaff scale on Succari oranges followed by Navel oranges then the least abundant on Baladi oranges. Generally, the calculated data on Succari oranges showed that, the population of P. pergandii reached the maximum during July and there were five highly variation periods in both the growing seasons of 2011-2012 and 2012-2013. The maximal percent of pre and adult females was observed during Spring and early Summer and reached 100% of the total counted individuals during October and December in the first year, but in the second one a higher population was recorded during Summer and early Winter months. The adult males were observed during Summer and Autumn months. Results showed also that the relationship between daily mean temperature and population density of chaff scale was weak, insignificantly negative in the two growing seasons (2011-2012 and 2012-2013) and also insignificantly but positive with relative humidity. That relationship with wind speed indicated weak positive significance in the first year and strong in the second season. The relationship between dew point and insect population was weak of positive significance in both growing seasons.

TOXIC ACTIVITY AND DELAYED EFFECTS OF FIVE BOTANICAL OILS ON THE FOLLOWING GENERATIONS OF AGROTIS IPSILON (HUFNAGEL) (INSECTA: LEPIDOPTERA: NOCTUIDAE) AFTER PARENTS TREATMENT.

The present study is carried out to evaluate the toxic efficiency and delayed effects of five botanical oils on the greasy cut worm Agrotis ipsilon (Lepidoptera: Noctuidae), as a trial for the attainment of a possible use of an alternative safe and effective phytochemicals against the insect-pest. So as to minimize or prevent the repeated usage of conventional insecticides, then reduce the environmental pollution as well as the occurring hazards to man and domestic animal due to the use of the pesticides alone. Four tested concentrations (0.5, 1.0, 1.5 and 2.5% v/v) from each of camphor, red basil, menthol, rose and anise oils, were bioassayed by treating the offered castor oil bean leaves, to the 4th instar larvae along 48h, under the laboratory higrothermic conditions of 25±2 °C and 65±5% R.H. The obtained results showed that the five tested oils were found to have more or less toxic activity and drastic effects on the inspected parameters of fitness components of the treated parent generation of the insect, in particular, pupae, emerged adult moths and laid eggs/female. In this respect camphor and red basil oils were highly effective, followed by menthol oil, anise oil and the least effective one was rose oil. Moreover, the assessed unprofitable delayed effects on the going on of the biological performance within the treated insects showed the adverse effects on the fitness components of the consequent generations (fs) post (p) one treatment with each of the bioassyed oils. The prevalence of adverse effects and disturbance in the going on biological performance through the period of (p) generation; which is followed by the distinct failure of insect development in (f1) generation were recorded for each of the tested menthol oil at 0.5 and 1.5% (v/v); camphor oil at 1.5 and 2.5% and red basil oil at 2.5% (v/v). While anise and rose oils were somewhat less efficient causing the distinct failure of the following generations up to the 3rd and/or the 6th ones. That observed distinct failure of the insect development could be attributed to the rapid or/and slow cumulative effect of the induced recessive lethal genes in both influenced sexes along the interval of the following developed generations (fs) after (p) one treatment, causing apparent adverse disturbance of the normal biological performance, which finally appears at the beginning of the failed generation.

EFFICIENCY OF PREPARED BAITS OF LONE OR/AND ADMIXED FOUR BOTANICAL OILS ON THE VIABILITY OF SUCCESSIVE RAISED GENERATIONS OF AGROTIS IPSILON (HUFNAGEL) (INSECTA: LEPIDOPTERA: NOCTUIDAE) AFTER TREATING THE PARENT ONES.

The present study is initiated to determine the toxic and delayed effects of four botanical oils on the greasy cutworm A. ipsilon, aiming to attain an alternative environmentally safe and effective phytochemicals against the insect-pest. Four botanical oils (camphor, red basil, menthol and rose oil) were added at rates of 0.5 and 1.0% (v/w). The tested oils were added alone, and/or admixed at proportional rate of 1:1 in the prepared baits against the exposed 4th instar till the 6th instar larvae of the insect. The study was run under the laboratory higrothermic conditions of 25±2°C and 65±5% R.H. The results showed that the tested baits of camphor, red basil and menthol oils at concentration rates of 0.5 and 1.0% (v/w) adversely affected the inspected parameters of fitness components of the treated individuals of parent (p) generation. They gave more or less fewer numbers of weak unviable adult-moths, which were either sterile or they laid few numbers of infertile eggs and died before the induction of (F1) progeny. That failure could be elucidated by the rapid occurrence of drastic effects on the biological performance of both the influenced sexes of adult-moths along the period of parent's development. Finally it ended by the inhibited induction of (F1) progeny. A delayed effect of the prepared baits of rose oil at 0.5 and 1.0% (v/w), was assessed on the following raised F1, F2, F3 and F4 generations after parent's treatment. The delayed effect was detected as less efficient latent effect on each of these consequently raised generations; characterized by the gradual decrease of the number of alive immatures and adult-moths. The effect was recorded as gradual increase of dead and malformed individuals and adult-moths. In addition to the gradual decrease of deposited and/or hatched eggs up to the 4th generation, which ended by the complete failure of the development. That failure could be also attributed to the cumulated effects of the induced recessive lethal genes in both the influenced sexes during the periods of raised F1, F2 and F3 generations. The recessive lethal genes caused drastic unprofitable effects that appeared at the beginning of the 4th generation that failed. Also, the tested baits (0.5 and 1.0%, v/w) of each of admixed camphor, red basil and menthol oil with rose oil (1:1), greatly affected the developmental parameters of the treated insects. The highest efficient toxicity and an adverse biological performance of the admixed camphor and/or red basil oils with rose oil at 0.5 and 1.0 (v/w), and menthol/rose oil at 0.5% (v/w) on the treated parent generation were detected. The previous treatment gave unviable sterile adults, which died before the induction of (F1) progeny. That recorded failure of (F1) proves the fastest toxic efficiency and a drastic biological performance which were entirely unable to induce (F1) progeny. The tested bait of mixed menthol/rose oils (1.0%, v/w), showed significant reduction in all studied parameters of F1 and F2 fitness components. The tested bait raised sterile unviable adult-moths of (F2) generation which furtherly ended by the distinct failure of (F2) development. This effect may be caused by the cumulative effects of the induced recessive lethal genes in both of the affected sexes through the developmental period of (F1) generation after (P) one treatment, inducing apparent drastic effects, which were revealed at the beginning of (F2) generation. Remarkably, the inspected faster or slower occurred toxicity and drastic biological performance of these admixed botanical oils, may be referred to the synergistic action for most of the evaluated mixtures or/and the additive one for menthol/rose oil (1.0%), which needs further investigation.

BIOEFFICACY OF PIPER RIBESIOIDES (PIPERACEAE) EXTRACTS AGAINST NILAPARVATA LUGENS STAL. (HOMOPTERA: DELPHACIDAE).

The extracts of stem and seeds of Piper ribesioides (Piperaceae) were prepared in hexane, dichloromethane, ethyl acetate and ethanol and evaluated for their efficacy against 3-day-old adult brown plant hoppers, Nilaparvata lugens Stal under laboratory conditions. The treatment was given topically and results suggest the dose dependent response related to exposure time. The ethyl acetate extract was the best with an LC50 = 738 ppm-, 24 h post-treatment. There was substantial increase in activity (LC50 = 27.298 ppm) with the increase in duration of exposure. This trend was observed in all treatments that suggests the potential of Piper ribesioides as an insecticide for N. lugens as an alternative control.

PROPOSED MEASURES OF CONTROL MANAGEMENT OF THE GRAPE MOTH, LOBESIA BOTRANA DEN AND SCHIFF (LEPIDOPTERA: TORTRICIDAE), IN REFERENCE TO INFESTATION PERCENTAGES, YIELD LOSS AND ECONOMICS OF CONTROL IN EGYPT.

This study aims to evaluate the efficacy of five measures; including the release of two strains of Trichogramma, Bacillus thuringiensis (B.t.). Sweetened B.t. and the environmentally friend insecticide (Tracer®), to manage the grape moth, Lobesia botrana that infested the grape vines c.v. "Thompson seedless " in Egypt severely during the two successive years of 2011 and 2012. In concern to the release of the worldwide, Trichogramma evanescens Westwood., the mean total grape yield ranged from 8.00 to 14.00 ton/fed and from 6.90 to 11.9, in respect to the two seasons and the mean infestation percentages fluctuated between 50.00 and 16.14; 43.48 and 21.01 in sequence for the same years. The corresponding grape bunches loss percentages averaged from 21.43 to 6.91; 18.63 to 9.00,respectively for the same periods of this study. Whereas, it was noticed that in releasing the indigenous T. bourarchae was more effective than T. evanescens in reducing all the above mentioned grape yield particularly. Applying Bacillus thuringiensis (B.t.) and/or adding sugar as a stimulant to improve yields reduced the infestation and the crop loss percentage. However, Bacillus thuringiensis mixed with sugar which overweighed the use of Bacillus thuringiensis alone. Although Tracer® provided good harvest in both years, but unfortunately it affected the grape berries components rather than the other treatments. Control plots indicated 48 and 50% infestation, with very low yield compared with the other five trials to manage the assigned insect pest. For the first time worldwide economics and profits were computed taking into account the whole market sale, the total control costs and the gross income to decide the most profitable treatment for the table grape growers under the Egyptian conditions. It was found that the mean (L.E.) profits/fed were arranged in a descending order as follows: 470.95, 513.28, 504.78, 500.82, 397.25 and 0.00 for Bacillus thuringiensis + sugar, Trichogramma bourarchae, Trichogramma evanescens Westwood, Dipel-2x®, Tracer® and control in respect in 2011. The corresponding values in the year 2012 were 453.85, 445.58, 427.18, 377.00, 349.18 and 0.00 for Trichogramma bourarchae, Bacillus thuringiensis + sugar, Dipel-2x®, Trichogramma evanescens Westwood, Tracer® and control in respect. The obtained results were analysed and discussed in the text.

Some ecological aspects on olive parlatoria scale, Parlatoria oleae (Colvee) infested plum and olive trees under irrigation system at Burg El-Arab area, Alexandria, Egypt.

Field studies were conducted under irrigation system at Burg El-Arab area (50 K.m. west of Alexandria city) to study some ecological aspects of Parlatoria oleae (Colvee) and its parasitoid, Aphytis maculicornis (Masi) that infested olive and plum trees during the two successive years of 2010 and 2011. Field observations revealed that the most of the inspected individuals occurred mainly on the branches of plum trees as compared with those found on leaves, but on olive the insect occurred on all the plant parts including fruits. On plum trees, the obtained data showed that the population of P. oleae reached the maximum during April, November and January in the first year, but in the second one it had four peaks of high population levels during March, August, November and January. The maximal percent as adult females was observed during March, September and January, whereas the adult males appeared only during October and November. The parasitized individuals by A. maculicornis represented higher rate of parasitization from March to August in the first year that extended to September in the second year. On olive trees under irrigation the population of Parlatoria scale and its parasitoid was relatively low. It had three high peaks, during March, December and February in the first year, while in the second one the population reached the maximum during March, December and February. The parasitoid Aphytis maculicormis appeared in March and April marking high percentage levels in the first year, noticeably it was nearly parasitized the scale insect all the year round.

Assessment of genetic relatedness in the honeybee Apis mellifera L. (Hymenoptera: apidae) colonies by using microsatellite loci.

In this study the relatedness was estimated between mother queen's colony and her daughters' queens' colonies, by extracting DNA from their individual workers offspring (N= 20) and using five microsatellite loci. Locus As indicated more diversity in the length of alleles from 130 to 162 PB with frequency from 0.05 to 0.1, followed by locus A76 that showed alleles lengths 210 to 340 PB with frequency 0.05 to 0.2 that means big diversity in the colonies individuals due to the numbers of drones mated with mother queen. On the other hand, A107 illustrated the weight of alleles from 179 to 205 PB with frequency 0.05 to 0.25. Loci B124 and ACOO6 also showed high frequency of 0.25 and indicated more relatedness. Through locus 8124 the Correlation coefficient was 1.00 between P.Q and F,.QO and 0.87 for P.Q and F1.Q1 and F,.Q3. A43 indicated relatedness through the correlation coefficient (0.968) between F.Q1.and F2.Q2. The microsatellites demonstrated that there was a genetic diversity within and between colonies.

Comparative studies of semi-artificial diets on the biology and the bionomics of the European corn borer, Ostrinia nubilalis Hübner (Or.: Lepidoptera, Fam. : Pyralidae).

Comparative studies of two semi-artificial diets (S.A.1 and S.A.2) as well as a natural corn diet were studied on the biology and bionomics of the European corn borer, Ostrinia nubilalis under laboratory conditions. The insect was successfully mass reared for ten successive generations at the conditions of 27 +/- 2 degrees C, 60-80% R.H. in addition of photoperiod of 6:18 (L: D) for larvae and 12:12 (L: D) for the other stages, respectively. Along ten successive generations, there were no significant differences between the larval periods for both artificial diets. The S.A.1 induced the shortest larval period (22.5 days) compared to the artificial diet S.A.2 (24 days) and the natural diet (25 days). Meanwhile, the rearing larvae on the natural diet revealed means of pre-pupal and pupal periods of 2 and 8 days which decreased to 2 and 6.5 days in both artificial diets (S.A.1 and S.A.2), respectively. However, the pupal weight and length were insignificantly increased in S.A.1 (121.7 g and 1.7 cm) than that in the natural diet (115.5 g and 1.8 cm) and were in the artificial diet S.A.2 (101.2 g and 1.7 cm), respectively. Moth longevity (pre-oviposition, oviposition and post-oviposition periods), was affected to a certain extent by the larval diets. The maximal moth longevity was recorded (15 days) for larva reared on the natural diets. On the other hand, the shortest period was observed (10.5 days) for the moth longevity in S.A.1. The artificial diet S.A.2 showed the moth longevity (13 days). The longest oviposition period was recorded (10 days) in the natural diet, while it was only (6.5 days) in the artificial diet S.A.1 compared with (8 days) in the artificial diet S.A.2. The number of the deposited eggs/female throughout the 10 successive generations was (400) in the natural diet, while the artificial diet S.A.1 revealed the least number (304.4) versus (358.2) in the artificial diet S.A.2. On the other hand, the number of hatched eggs/female were (320) in the natural diet, versus (310.9 and 256.5) in the artificial diet S.A.2 and S.A.1, consequently. The highest mean of hatchability percent was 86.93% resulted in the artificial diet S.A.2 compared to. 83.92% in the artificial diet S.A.1 and 80% in the natural diet. It was observed that the shortest total generation period found (41.5) days in the artificial diet S.A.1 while it was (50 and 45.5)days in the natural diet and the artificial diet S.A.2, consequently. The results declared that the artificial diet S.A.1 is a suitable artificial diet as it is considered mass rearing of the European corn borer, Ostrinia nubilalis Hub.

Different patterns of acid and alkaline phosphatases activities during embryogenesis and in emerged adults of Helicoverpa armigera (Lepidoptera: Noctuidae).

The acid phosphatase and alkaline phosphatase activities were studied in the developing eggs and in aging ovary and testis of pot-emerged adult of the cotton bollworm, Helicoverpa armigera at different time intervals from 0-72 hours. Acid phosphatase activity was higher than alkaline phosphatase and acts as cyclic during embryonic development. Alkaline phosphatase activity was slightly increased in the freshly laid eggs but decreased more sharply than acid phosphatase during embryonic development. In all groups of post-emerged adults, acid phosphatase activities were much greater than alkaline phosphatase at any given stage of progressively increasing age. Both enzymes were noticed to be cyclic in the post-emerged mated and non-mated adults. A conspicuous difference was noted between the activities of these enzymes in ovaries and testes of mated and non-mated adults. This phenomenon could be due to the periods of spermatozoa production in the testes and yolk accumulation in oocytes and ovulation. Mating could be also a factor that affected the phosphatases in both males and females.

Efficiency of guva and lemon grass fine dusts on the potato tuber moth Phthorimaea operculella (Zeller) (Lepidoptera: Gelechiidae).

The present study was initiated to elucidate the effect of potato tubers treatment using fine dusts of Psidium guajava, Cymbopogon citratus, talc powder and their progressive dilutions(w/w) on the fitness components of raised generations of the potato tuber moth (PTM), Phthorimaea operculella. Results showed a direct as well as cumulative delayed effect of the tested plants fine dusts, either alone or admixed with talc powder in progressive dilutions from 5% up to 50% w/w on the viability of developing immatures and potentiality of adult moths. The revealed effects of each of the tested crude plant fine dusts or talc powder alone and/or their progressive dilutions (w/w) could be explained briefly as gradual significant shortening of life span of both sexes, prolongation of larval duration, reduction in number of raised pupae, increase of malformed ones, sharp decrease in the rate of emerged moths, deposited eggs, and developing of immatures; According to lower used dilutions of each tested plant fine dust from 5% to 20%, the complete inhibition of reproductive potential of both adult sexes, the going on metamorphic development of deposited eggs and/or raised immatures of the following generation, after the treatment of parent one, had been revealed the following distinct failure of: a) F1 development after former treatment of parent generation with the higher concentrations of 30-50% of both tested plant fine dusts and the lower prepared dilutions (10% and 20% (w/w)) of both the tested Psidium guajava and (20% (w/w)) Cymbopogom citratus plant fine dusts, resulted in fewer number of the emerged moths that were unviable, weak, sterile and died before induction the F1 progeny, b) F2 development due to the former treatment of the parents with talc powder, Psidium guajava fine dusts alone or its prepared dilutions of (5% (w/w)) and Cymbopogom citratus dilution of (10%(w/w)) gave unviable weak and sterile moths unable to induce the F2 progeny, c) F3 development post former treatment of the parent generations with Cymbopogom citratus dilution of 5% (w/w) induced unviable sterile moths and died after emergence and d) F4 development owing to the former parent treatment with Cymbopogon citratus fine dust alone; The complete failure of each of the above mentioned generations could be attributed to the cumulative effect of induced recessive lethal genes in both sexes along the extended period of each of these following generations, post former treatment of parent one, causing apparent undesirable effects, that appeared at the beginning of each of them.

Mass rearing of the pink corn borer, Sesamia cretica Led. (Lepidoptera: Noctuidae) larvae, on semi artificial diets.

The effect of two different semi-artificial diets (S.A.D1 and S.A.D2) as well as a natural corn diet on the biology and bionomics of the pink stem borer, Sesamia cretica was studied under laboratory conditions. The insect was successfully mass reared for ten successive generations at the conditions of 27 +/- 2 C degrees and 60-80% R.H. In addition, a photoperiod of 0:24 (L:D) for larvae and 12:12 (L:D) in concern to the other stages, respectively. ALong the ten successive generations, there were no significant differences between the larval periods for both the artificial diets. The S.A.D2 induced the shortest (24.0 days) larval period compared with the natural diet (27.5 days) and S.A.D1 (31.5 days). Rearing larvae on the natural diets revealed a pupal period of 11.0 days, while it was 10.0 days and 8.5 days for the artificial diets (S.A.D1) and in (S.A.D2), in respect. Moth longevity (pre-oviposition, oviposition and post-oviposition periods), to a certain extent, was affected by the larval diets. The maximal moth longevity (13.0 days) was observed for larva reared on corn plants (4, 8 and 1 days). On the other hand, the shortest period (10.5 days) of moth longevity was noticed in SAD2 (1, 9 and 0.5 days). S.A.D1 showed 11.0 days moth longevity (3,7 and 1 days). The longest oviposition period (9.0 days) was recorded in the artificial diet S.A.D2, while it was only 7.0 days in the artificial diet S.A.D1 compared with 8.0 days in case of the natural diet. The number of deposited eggs increased with the progress of the 10 successive generations (G1:G10) from 150 to 265 and from 384 eggs to 564 eggs / female for the S.A.D1 and S.A.D2, in sequence. The highest mean number of deposited eggs per female (564) was for the derived females from larvae fed on the artificial diet in G10 of S.A.D2. The rate of the deposited eggs in S.A.D2 was gradually increased (from 9.70 to 61.14% increase) more than those reared on the natural diet throughout the ten generations. The highest significant percent hatchability (92.69%) has been resulted from the artificial diet SAD2. But, it has been decreased to 85.59% in the artificial diet S.A.D1 in comparison to 65.71% in the natural diet. In addition, the significant shortest total generation period was 44.0 days resulted from the artificial diet S.A.D2, while it was 53.5 and 54.0 days for corn plants and the artificial diet S.A.D1, consequently. In short, results indicated that the S.A.D2 could be considered as a suitable artificial diet for a feasible mass rearing of the pink corn borer, Sesamia cretica led. The S.A.D2 showed the shortest larval, pupal and life span for the generation periods. Moreover, it induced the longest oviposition period and the highest mean number of deposited eggs per female and the highest significant percent of eggs hatchability/fertility. The utilization of this artificial diet (S.A.D2) would supply the researchers with high-quality insects in adequate numbers, at specified times and specific stages of development for the bioassay, toxicological and biological studies.

Efficacy of some oils and chemical compounds on Insignorthezia insignis (Browne) (Hemiptera: Ortheziidae) infesting Lantana camara in Alexandria, Egypt.

Field and laboratory experiments were conducted in March, 2008 in El-Nouzha garden, Alexandria governorate. Pre-and post treatment inspections of the insects were examined and recorded before and after (2,4,8, and 12 weeks). Spraying was applied to evaluate the efficiency of the tested compounds, [Mineral oils (KZ oil and Star oil); IGRs (Chlorfluazuron, lufenuron and pyriproxyfen); Neem oil; emamectin benzoate and thiamethoxam]. Percentages of reduction were calculated. The ensign scale insects Insignorthezia insignis (Browne) were collected from treated Lantana camara shrubs to investigate the effect of the tested chemicals on Aspartate transferase (AST), Alanine transferase (ALT) and Alkaline-phosphatase (ALPK) of the insect enzymes activities. From the obtained results, it could be concluded that the tested materials gave good results for controlling both adult and immature stages of the ensign scale insect Insignorthezia insignis (Browne) that infested Lantana camara shrubs, through affecting enzymes activities of the assigned insect pest.

Efficacy of five volatile oils and their mixtures against the soft scale insect, Saissetia coffeae (Walker) (Hemiptera: Coccidae) infesting the Sago palm, Cycas revoluta in Alexandria, Egypt.

Five tested plant volatile oils and their mixtures were evaluated for controlling the coccid, Saissetia coffeae (Walker) on growing Sago palms Cycas revoluta in Antoniades public gardens, Alexandria, Egypt. The tested volatile oils at concentration rates of 0.5, 1 and 1.5% (v/v) were: Camphor 20%, Dill 20%, Rose 30%, Peppermint 20% and Clove 30% (v/v). Their mixtures were : Camphor/Peppermint, Camphor/Rose at a rate of 1:1, Camphor/Rose/Peppermint at 1:1:2 rate and Camphor/Rose/Dill at 2:1:1 rate. The results, as a general mean of residual reduction percent for the whole inspection intervals of the test lasted 2 days up to 9 days post treatment, indicated that the superior volatile oils in reducing the insect were both Camphor and Rose, followed by Dill, Peppermint and the least efficient one was the Clove oil. The evaluated mixtures of the volatile oils showed that each of Camphor/Rose/Peppermint, Camphor/Rose and Camphor/Peppermint mixtures attained a higher rank of efficiency against that of the assigned soft scale insect.

Comparative analysis of three scale insect species populations (Hemiptera: Coccoidea: Diaspididae) and their parasitoid, Aphytis diaspidis(Howard) on pear trees in Burg el-Arab area, Alexandria, Egypt.

The infestation abundance of each of the inspected scale insect species: San Jose scale, Diaspidiotus perniciosus (Comstock), Greedy scale, Hemiberlisio rapax (Comstock) and Olive scale, Parlatoria oleae (Cloveé) on pear trees, more or less varied as the months of each growing season differed. The comparative abundance percentages in both seasons of 2004-2005 and 2005-2006 were (51.80 and 51.40), (41.20 and 40.90) and (7.10 and 7.70) of the counted individuals of the grand total of H. rapax, D. perniciosus and P. oleae, in respect. In other words, the Greedy scale (GS) was the highly abundant scale followed by the San Jose scale (SJS), but the olive scale represented the lowest one. The more or less increased and/or decreased abundance of each of the investigated scale insect species pointed to the existence of three overlapping generations throughout the season which were characterized by fluctuating peaks of population densities of the studied pests during the months of each annual season: autumn, winter, spring and summer.

Ultrastructure and description of the first immature stage of four different scale insect species (Hemiptera: Coccoidea) in Egypt.

The first stage of four different species belonging to three families of the super family; Coccoidea were described and illustrated by using the scanning electron microscope. These species: Mycetaspis personata (Comstock) and Fiorinia fioriniae (Targioni Tozzetti), pertaining to the family Diaspididae; Pulvinaria psidii (Maskell) (Family: Coccidae) and lcerya seychellarum seychellarum (Westw.) of the family Margarodidae. The dimensions of the first stage (crawler), as well as some taxonomical aspects were examined and discussed. The obtained data showed that the first instar of the mealybug, I. seychellarum seychellarum gave the largest diameter of 299.33 +/- 0.94 pm in length and 183.44 +/- 0.17 microm in width followed by the diaspidid species, F. fioriniae recorded 208.1 +/- 0.78 microm in length and 178.96 +/- 2.34 pm in width; while the coccid species, P. psidii measured 119.17 +/- 0.85 microm in length and 74.83 +/- 1.03 microm in width and the smallest first stage crawler was for the diaspidid, M. personata measured 85.50 +/- 0.41 microm in length and 63.88 +/- 0.27 microm in width. The modes of assigned insects in protecting their eggs were also discussed briefly.

Efficacy of five volatile oils and their mixtures against the mealybug, Icerya seychellarum seychellarum (Westw.) infesting Sago palm, Cycas revoluta in Alexandria, Egypt.

Five tested plant volatile oils and their mixtures were evaluated for controlling the Margarodid, Icerya seychellarum seychellarum (Westw.) on growing Sago palms in Antoniades public gardens, Alexandria, Egypt. The tested volatile oils at concentration rates of 0.5, 1 and 1.5 % (v/v) were as follows: Camphor 20%; Dill 20%; Rose 30%; Peppermint 20% and Clove 30% (v/v). Their mixtures were Camphor/Peppermint; Camphor/Rose; at a rate of 1:1 Camphor/Rose/ Peppermint at 1:1:2 and Camphor/Rose/Dill at 2:1:1. The calculated results as general mean of residual reduction percent for the whole inspection periods of the test indicated that the superior volatile oils in reducing mealybugs were both Camphor and Rose, followed by Dill, Peppermint and the least efficient was Clove volatile oil. The evaluated volatile oils mixtures showed that each of Camphor/Rose/Peppermint, Camphor/Rose, and Camphor/Peppermint mixtures occupied a higher rank of efficiency against the treated mealybugs.

Ecological studies on San José scale, Diaspidiotus perniciosus (Comstock) (Homoptera: Diaspididae) as a new insect pest on pear trees in Burg El-Arab area, Alexandria, Egypt.

The San José scale, D. perniciosus (Comstock) (Homoptera: Diaspididae) was noticed on pear trees all the year round in Burg El-Arab area (50 km West of Alexandria). Bio ecology and population fluctuations of this serious scale insect were carried out during the two subsequent seasons of September, 2004 until August, 2006. The calculated infestation rates (%) assured the presence of three peaks in both seasons. The estimated densities of fluctuating individuals of D. perniciosus on the inspected pear trees showed two distinctly prominent peaks, in addition to an overlapping one between them. It means, that the San Josè scale, D. perniciosus had three overlapping annual generations on pear trees in Burg El-Arab area under an irrigation system. The individuals of all stages could be found on trees all over the year. The population of the inspected immature stages; adult females and adult males were recorded and discussed as well as the parasitized individuals by the aphilinid parasitoid, Aphytis diaspidis (Howard) (Hymenoptera: Aphelinidae). The population density of the San José scale (SJS) reached its maximum during spring, folLowed by summer, winter, whereas the least percentage was recorded in autumn months. The obtained data showed also variable effects of the prevailing abiotic factors on the dynamical oscillation of (SJS) individuals. The daily mean temperature and the dew point were not the dominant efficient physical factors. On the contrary, it has been proved that there were either significant strong negative or positive relationships between daily relative humidity, wind speed, infestation rate, and population density of this studied insect pest.

Ultrastructure of egg shell of four different Coccoidea species in Egypt.

The present study was initiated to perform a comparative measurements of egg dimension and structure of four different species pertaining to three families of the super family: Coccoidea. These species were: Mycetaspis personata (Comstock) (Diaspididae), Ceroplastes floridensis (Comstock) (Coccidae), Pulvinaria psidii (Maskell) (Coccidae), and Icerya seychellarum seychellarum (Westw.) (Margarodidae). The studied species differed in their means of egg laying and chorion structure, which may explain the mode of insect protection. The dimensions of chorion shell, as well as the ultra structure of the egg shell of each species were examined and discussed.

Scale insects and mealy bugs (Homoptera: Coccoidea) attacking deciduous fruit trees in the western north coast of Alexandria, Egypt.

This investigation covered a survey of scale insects and mealy bugs infesting ten growing species of deciduous fruit trees in three localities in Alexandria govemorate. These localities were Merghem, Burg El-Arab, and El-Nahda about 50 Km. West of Alexandria under both rain-fed and irrigation system conditions. The common inspected fruit trees were fig, white mulberry, pomegranate, apple, pear, apricot, European plum, peach, almond, and persimmon. It was shown that a group of twenty scale insects and meaty bug species pertaining to fifteen genera belonging to six families of the super family: Coccoidea were collected and identified during the elapsing period from January to December, 2004. Among these species, Diaspidiotus perniciosus (Comstock) was recorded for the first time in Egypt. In the present study, many insect and non-insect parasitoids and predators were also found associated with these scale insects and mealy bugs on deciduous fruit trees in the three concerned localities throughout this investigation. These natural enemies were identified and recorded.

Ecological studies on the greedy scale, Hemiberlisia rapax (Comstock) (Homoptera: Diaspididae) on pear trees in burg El-Arab area, Alexandria, Egypt.

The greedy scale, Hemiberlisia rapax (Comstock) causes economic damage on pear trees under irrigation system in Burg El-Arab area (50 Km. West of Alexandria). The infestation rate of H. rapax reached its first maximum rate during August to October, and the second one occurred from January to March. The 1st highest peak of insect population occurred during September and October; the second was during January and February, and the third one corresponded to April for the 1st and the 2nd successive seasons. The statistical analysis was performed to determine the relationship among the weather factors of mean daily temperature, daily relative humidity, wind speed, and dew point in relation to the population activity of Hemiberlisia rapax. The immature stages had two peaks of fluctuation during October to November and July to August. The adult females reached their maximum rates during winter and spring months. Adult males appeared in late March in few numbers. The insect was parasitized by Aphytis diaspidis (Howard) (Hymenoptera: Aphelinidae) in maximum numbers in June and July. This parasitoid had three overlapping generations all the year round. The first in September-October; the second extended from March to May; while the third one lasted from July to September.