ALY H. RASMY
Plant Protection Dept., National Research Centre, Dokki , Cairo , Egypt .

Key Words: Predacious mites, Biological control , Egypt .

SEASONAL ABUNDANCE OF APHIDS AND THEIR NATURAL ENEMIES IN WHEAT FIELDS IN UPPER EGYPT .

A.H.EL-HENEIDY
Biological Control Dept., Plant Protection Research Institute, ARC
Dokki, Giza , Egypt

ABSTRACT

Seasonal abundance of certain biocontrol agents associated with aphids in wheat fields was studied for the two seasons 1988/89 and 1989,90 in two districts of each of Assiut and Sohag Governorates in Upper Egypt. Four species of aphids were recorded infesting wheat plants during the study. The highest rates of aphid infestation were observed during March. Six groups of predators were counted weekly. Highest numbers of predators were recorded during April. Coccinellids were the most abundant predatoiy species in wheat fields. Highest parasitism % was estimated in early April and late of February in 1988/89 and 1989,90 seasons, respectively in the two Govemorates. Four hymenopterous parasitoid species were identified parasitizing aphids in wheat fields.

Key Words: Aphids, Predators, Parasitoids, Wheat , Egypt .

INSECTS INHABITING SAFFLOWER AND THE ROLE OF PREDATORY INSECTS IN MANSOURA , EGYPT .

M.E. RAGAB
Plant Protection Dept., Fac. of Agric., Mansoura Univ. , Egypt .

ABSTRACT

Field studies were carried out for two successive seasons 1989 and 1990 to survey the main insects inhabiting safflower plants at Mansoura district, Egypt . The collected insects included 14 injurious and 16 beneficial species. The injurious species were affiliated to the following sex orders: Thysanoptera, Homoptera, Diptera, Hemiptera, Lepidoptera and Coleoptera, of which the first two orders were the main ones. Thrips tabaci Lind., Trypaneaeluta Meigen and Oxycarenus hyalinipennis Costa. were the main insects infesting safflower heads as indicated by their catch numbers. Insect predators recorded were eleven species, and Oriusalbidipennis Reut. was the most dominant one. The numbers, population fluctuations and ratios of the main injurious and predatory insects are presented. The role of predators in suppressing the poopulations of noxious insects was also discussed.

Key Words: Safflower, Carihamustinctorius L., Insect pests, Predatory insects.

M.O. KOLAIB
Faculty of Agric., Menoufia University , Shebin el-Kom, Egypt .

ABSTRACT

Rate of parasitism by Diaeretiellarapae (MTntosh), on the cabbage aphid, Brevicoryne brassicae (L.), as well as rate of hyperparasitism on D.rapae were recorded through September, 1989 till August, 1990 at Shebin El-Kom district, Egypt . Results revealed that D.rapae occurred during all months with highest activity during November, December, and January as rates of parasitism were 93.9, 96.4, and 83.9%, respectively.The parasitoid, D.rapae was parasitized by two hyperparasitoids, i.e. Pachyneuron aphidis Bouche, first record in Egypt , and Alloxysra sp. P. aphidis was found during all months except August and September. Its maximum activity was observed during January, February, and March as the rates of hyperparasitism reached 74.33, 87.07, and 83. 12%, respectively. Rates of hyperparasitism by Alloxysta sp. did not exceed 10%. The total hyperparasitism by the two species reached 91% in February.

Key Words: Cabbage, Aphids, Parasitoids, Hyperparasitoids , Egypt .

SAMIA A. G. METWALLY
Plant Protection Research Institute, Agric. Res. Center , Dokki, Cairo , Egypt

ABSTRACT

Liriomyza trfolii (Burg.). is considered one of the main pests of cowpea in Egypt . The population dynamics of the pest and parasitoids species associated with it were studied for two growing seasons, 1989 and 1990. Highest pupal population (1284) of L. trifolii was observed by the end of September, while the lowest (210) was observed by mid-August. Four hymenopterous parasitoids, Ilallicoptera circulus Walker , Anagriss sp., Chrysonotomyia sp. and Hemiplarsenus zilahzsebessi Er- dos were recorded, for the first time in Egypt , associated with the pest in cowpea. Highest rates of parasitism (33.09%) were estimated by mid-October, while the lowest rate reached (8.0%) by mid-July. Obtained data showed that Anagrus sp. and Chrysonotomyia sp. recorded the relatively highest rates of parasitism (6.3 and 5.2%, respectively), while H. zilahisbessi recorded the lowest (0.81%). Data also indicated that the most active period of the parasitoids, Anagrus sp., 11. circulus and Chrysonotomyia sp. took place during October and in case of H. zitahisebessi, it was during August

Key Words: Liriotnyza trifolii, Population, Parasitoids Cowpea, Egypt .

L.M. SHANAB
Plant Protection Dept., Fac. of Agric., Mansoura Univ. , Egypt .

ABSTRACT

Diethyl ether, chloroform and acetone were used as solvents for extracting the sex pheromone of Lepidosaphes beckii females. The preparations in diethyl ether or chloroform exhibited a positive response to L. beckii males. The highest response was obtained by using diethyl ether extract. Moreover, the highest number of the ectoparasitoid Aphytis lepidosaphes was caught by this extract. Diethyl ether extract lost its biological activity after 48 h under field conditions. The number of males attracted in pheromone traps increased as pheromone concentrations increased. Under laboratory conditions L.beck i males elicited mating behavior in response to diethyl ether extract. The proportion of males which exhibited mating behavior increased in proportion to increasing female equivalent concentration.

Key Words: Diaspididae, L. beckii, Sex pheromone, Bioassay, Extract.

LIFE HISTORY AND MORPHOLOGY OF THE LARVAL PARASITOID, EPYRIS NIGER WESTWOOD (BETHYLIDAE : HYMENOPTERA)

KHALAFALLA S. AHMED
Dept. of the Biological and Geological Sciences,
Faculty of Education, Ain Shams University .

ABSTRACT

Epyris niger Westwood is a solitary larval ectoparasitoid on coleopteran species such as Tribolium confususn Jaq. duval and Triboliwn caslaneu,n Hbst. At 262oC and 65±5 $ R.H. The egg. larval, prepupal and pupal stages lasted 1,7,6, 9,2, 0 and 13.3 for female and 1, 7,5, 2, 2, 0 and 11.6 days for male, respectively. The preoviposition, oviposition and postoviposition periods were 5, 3, 14.9 and 2.1 days for the mated females at the same temperature, respectively. The daily number of eggs laid per female was 8.2 while the total number per female during the life span was 123.2 eggs. The females lived longer than males. They also lived longer when mated and fed on honey (22.3 days) than virgin starved ones (1.9 days).

Key Words: Parasitoid, E. niger , Morphology, Biology, Life cycle

F.A. ABDEL-GALIL, Y.A. DARWISH, A.M.K. EL-SAYED AND G.H. ABU-EL-HAGAG
Plant Protection Dept., Fac. of Agric. Assiut University, Assiut, Egypt

ABSTRACT

Threshold of development and the thermal units (day-degrees) required for the development of the egg, larval and pupal stages of the common green lacewing, Chrysoperla carnea Stephens reared on Aphis gossypii Glover at constant temperatures ranged from 18 to 34 ‘C were determined. Temperature thresholds of 6.5, 7.0 and 13.13 ‘C were assessed for the egg, larval and pupal stages, respectively. About 79, 206 and 114 day-degrees, were needed for egg, larval and pupal development, respectively. A total of 390 thermal units was required for a predator, generation.

Key Words: Chrysoperla carnea, Developmental threshold, Temperature, Biological control.

INFLUENCE OF PHOTOPERIOD AS AN ENVIRONMENTAL FACTOR ON THE BIOLOGY AND FEEDING CAPACITY OF THE LADYBIRD BEETLE COCCINELLA UNDECIMPUNCTATA L. (COLEOPTERA : COCCINELLTDAE)

M.E. RAGAB, AND L.M. SHANAB
Plant Protection Dept., Fac. of Agric, Mansoura Univ. Egypt

ABSTRACT

The influence of three different photoperiods, i.e. 8/16, 12/12 and 16/8 hours light/dark per day on larval and pupal duration, prey consumption and fecundity of Coccinellaundecimpunctata L. was investigated. The experimented photoperiods had a significant effect on the durations of the first and second larval mstars and consequently affected the total larval duration. Also, the pre-oviposition period was greatly influenced. The intermediate photoperiod (12/12 h. L.D) is the most favourable light regime that increases prey consumption and fecundity of the predator.

Key Words: Coccinellids, Photoperiod, Biology, Feeding capacity

LAILA A. ABD ALLAH
Plant Protection Dept. Fac. of Agric. Mansoura University , Egypt

Key Words: Insecta, Exochomus flavAves , Thershold temperature, Thermal constant.

LAILA A.ABDALLAH
Plant Protection Dep. Fac. of Agric. Mansoura University

ABSTRACT

A biological study was carried out on the insect predator Exochoiniss Jiavipes (Thub.) at constant temperatures of 20,25 and 30'C. Rearing of the predator was conducted when fed on the cotton aphid, Aphis gossypii Glover. Results reported for immature stages revealed that the larval feeding capacity attained its maximum during the fourth larval instar. Detailed data about durations and feeding capacity of various larval instars were given. Results concerning the daily rate of prey consumption for the adult predator, male and female, and female fecundity were also given. Highly significant differences in longevity, rate of consumption, and female fecundity were obtained due to tested temperatures. The results assured the efficiency of E. flavipes in its active stages, larval and adult, in controlling A . gossypii at the all tested temperatures. Rate of consumption increased with the increase of temperature in the studied range (20-30'C.).

Key Words: Predators, Exochomus flavipes, Aphis gossypii, Temperature, Efficiency.

INFLUENCE OF FLUCTUATING PATTERN OF TEMPERATURE ON THE BIOLOGY OF THE PREDACIOUS MITE PHYTOSEJULUS PERSIMILIS ATHIAS-HENRIOT

A.Y.M. EL-LAITFIY
Acarology Unit, Plant Protection Dept., National Research Centre, 12311 Dokki Cairo , Egypt

ABSTRACT

The present investigation aimed to study the biology of the predatory mite Phyroseiulss persimilis Athias-Henriot under temperature which would prevail in spring season in protected cultivation in Egypt . P. persimilis was reared on a daily regular fluctuating temperature i.e. 39-41'C for six hours, then temperature was decreased gradually to 22 ‘C for 18 hours. Relative humidity in the rearing incubator varied between 50-85% according to temperature. Eggs of P. persimilis developed to the adult stage after 3.35 and 3.6 days for adult female and male respectively. The daily oviposition of adult female averaged 2.87 eggs per female. Immature stages of the predatory female and male consumed 17.0 and 10.33 eggs of the prey Tetranychus urticae Koch respectively, before maturity, while the daily consumption of adult female averaged 29.7 eggs. This study revealed the adaptability and efficiency of P. persimilis as a biological control agent of two spotted spider mite T. urlicae under the temperature pattern used herein.

M.A. RAKHA, M.E.E. EL-NAGGAR AND I.I. IL-SEBBAEY
Agric. Res. Centre, Plant Prot. Res. Institute, Dokki , Giza , Egypt

ABSTRACT

Biological studies on Cheyletus malaccensis (Oud.) were carried out in laboratory at 27'C & 70% R.H. Laboratory experiments showed that eggs of Lasioderma serricorne L. seem to be a very adequate prey for this predaceous mite. Duration and feeding capacities of the various stages of this cheyletid predator were recorded. Longevities of females and males lasted 603 and 29.6 days, respectively. During larval, protonymphal and adult stages, the male consumed 2.0, 4.2 and 2.6 eggs, while the female consumed 2.3 ,3.6 and 106.4 eggs, respectively.

Key Words: Predaceous mites, Biocontrol, Cheyleltidae, Lasioderma serricorne.

MOHAMMED A. HUSSEIN, ADEL K. EL-SAYED AND NADIA M. LOTFY.
Entomology Dept., Faculty of Science, Am Shams University .

ABSTRACT

The use of Bacillus ihuringiensis H-14 and B. sphaericus form one of the most important group of biological control agents against mosquito larvae. Data proved that the two fractions of mitochondrial ATPase (Na, K and Mg) in larvae of Cider pipiens and Aedes caspisu Pal, were more sensitive to B. ihuringiensis rather than B. sphaericus. On the other hand, the inhibitoTy action of the two bacterial agents on the ATPase fractions of C. pipiens. There is a positive correlation between post treatment time and ATPase inhibition.

Key Words: Bacillus, Mosquito, ATPase

G.H. SEWIFY AND A.M. MABROUK
Cairo University , Faculty of Agriculture, Dept. of Economic Entomoloy, and
Dept. of Agricultural Zoology and Nematology , Egypt .

ABSTRACT

Laboratory bioassay of the fungus Verticillium lecanii included different stages of the citrus brown mite, Eutetranychus orientolis under two different temperatures (20 and 27'C). The fungus proved virulent against all stages of the mite. Treatment of the eggs resulted a reduced rate of hatchability. None of the fungal treated eggs hatched at 20'C and only 15% hatchability was obtained at 27'C. Newly hatched larvae from treated eggs failed to develop and died soon after emergence. It was evident that, immature and mature stages were susceptible to fungal infection. Also, newly deposited eggs appeared more susceptible to infection than those about to hatch (7 day old). However, none of larvae, hatched from treated eggs, survived the Treatment. This prelimenaiy results may suggest a promising potential of the fungus as a biocontrol agent against the mite.

Key Words: Entomopathogenic fungi, Verticilliwn lecanii, Tetranychid mite.

BIOLOGICAL STUDIES ON THE MALACOPHAGOUS PREDATOR LIMNOGETON FIEB ER! MAYR (HEMIPTERA: BELOSTOMATIDAE.)

K.T. AWADALLAH, M.F.S. TAWFIK, F. YOUSIF* and K.M. AZZAM*.
Biological Control Laboratory, Faculty of Agriculture, Cairo University , Giza .
* Medical Malacology Department, Theodor Bitharz, Research Institute, Embaba , Egypt .

ABSTRACT

The biology of the malacophagous belostomatid, Limnogeton fieberi Mayr was studied in association with the two snail species Biotnphalaria alexandrina and Hetisoma duryi (at 18-2WC). The durations of the various stages of this predator together with the rate of mortality among immature forms and fecundity were estimated under this feeding condition. It appeared that B. alexandrian, the intermnediate host of Schistosoma inansoni, is more adequate prey than H. duryi and accordingly it could be considered one of the efficient biological control agents of this harmful snail.

Key Words: Biocontrol, Predator, Limnogeton fieberi, Snails.

M.F.S. TAWFIK, K.T. AWADALLAH, F. YOUSIF* AND K.M. AZZAM*.
Biological Control Laboratory, Faculty of Agriculture, Cairo University , Giza , Egypt .
* Medical Malacology Department, Theodor Bilharz Research Institute, Embaba , Egypt .

ABSTRACT

Feeding capacity of the various feeding stages of the belostomatid Limiwgeronfieben upon the two snails, Biomphalarta alexandrina and Ilelisoma duryi was estimated. During the nymphal stage of the predator, this capacity increased progressively in the successive instars, while in the adult stage it appeared higher on II. duryi than on, Balexandrina and in the female than in the male. Observations of the factors affecting rate of consumption upon the last snail showed that this rate increased as temperature increased from 15CC to 30'C. It also increased, but at a decreasing rate with the increase of prey-density. On the other hand, the depth of water did not affect consumption that increased as the size of water decreased.The prey preferability of L. fieberi towards the different snail species living on its natural habitat could be arranged descendingly as follows: Bulinus Iruncatus, Ilelisoma duryi and physa acuta, Biomphalaria alexandrina, Lymnaea cailliaudi, Planorbis planorbis and lastly G. ehrenbergi. The most preferable species was B. truncarus; the intermediate host of Schistosoma haematobium.

Key Words: Predator, Limnogeton fiebeni, Snails, Consumption.

SALWA K. MOHAMMED AND FATHEY H. A. NEGM*
Entomology Dept., Faculty of Science, Am Shams University , Cairo , Egypt
*Plant Protection Institute, Ministry of Agriculture, Giza , Egypt .

ABSTRACT

A list of 2 subfamilies, 5 general and 20 species of family Conopidae occuring in Egypt as well as, keys to all taxa are presented. New taxonomic situations and synonyms according to recent taxonomic status are taxonomically studied.

Key Words: Diptera, Conopidae, Taxanomy , Egypt .

EFFECT OF MELIA AZEDARACH EXTRACT ON EARIAS INSULANA (BOISD.) AND PECTINOPHORA GOSSYPIELLA (SAUNDERS).

AMIRA M. RASHAD, SUZAN H. TAHER, SONIA M. NAGUIB and N.M. ABD EL-SALAM
Plant Protection Research Institute, Dokki, Giza , Egypt .

ABSTRACT

Crude extract of the Meiw azedarach (Meliaceae) leaves was tested at different concentrations against the cotton bolloworms,Eariasinsulana (Boisd.) and Pectinophoragossypiella (Saunders). Obtained results indicated that highest concentrations increased mortality of newly hatched larvae of the two species, prolonged larval and pupal durations and reduced moths emergence too. LC 50 was 0.04623 and 0.53235 for E. insulana and P. gossypiella, respectively. Due to the toxicity and! or antifeeding effect of this extract, such substances could be used as pest control agents in integrated pest control programs but they still require further studies under field conditions.

Key Words: Melia azedaracl, Extract, Boll worms

I.M. KELANY, M.A. EL-DEEB and A.A. EL-FISHAWI
Faculty of Agriculture, Zagazig University , Zagazig , Egypt

ABSTRACT

A pasteform consisted of 150 g wheat bran, 50 g milk powder, 3 g brewer's yeast and 300 ml. water was used as standard rearing medium for the larvea of Musca domesfica. L. The medium was treated with an aqueous neem, Azedirachta indica A. Juss. seed kernel extract (ANSKE); 50 g seed kernel/litre of medium. Third in- star larvae of M. domestica were fed on the treated medium until pupation. Such treatment delayed larval pupation, reduced pupal weight, inhibited adult emergence and caused various malformations for emerged adults.

Key Words: Aqueous Neem, Azadirachta indicq Extraction, House fly.

M.F.S. TAWFIK
Parasites Laboratory, Plant Protection Dept., Faculty of Agriculture, University of Cairo , Egypt .

ABSTRACT

In this investigation, the actual way of dissociation, stnicture in various stages and function of the teratocytes of Apanteles glomeratiss and their fate in the normal host Pieris brassicae L. were described in details. The nutritive role of these elements played towards the parasite larvae is now considered the main function, while their role in protecing them from capsulation appears secondarily and occurs indirectly. They do not represent a special adaptation for the latter role.

SCIENTIFIC NOTE

 

Egyptian Journal of Biological Pest Control

(Egypt. J. Biol. Pest Control)
Volume 1 (2) 1991

A.M. HEKAL
Faculty of Agriculture, Am Shams University , Cairo , Egypt .

ABSTRACT

Biology and habits of Elasmus plazyedrae Ferr., a gregarious ectoparasitoid of diapausing larvae of Pecrinophora gossypiella (Saund.) were studied at 25 0 C and 65% R.H . Developmental durations of immature stages and feeding habits were estimated. Number of developing progeny of virgin females on a single host larva exceeded that of mated ones . Sex tatio of males to females was 1:3.5, while unmated females produced males only. Mating occurs soon after adult emergence . Mated females laid 32.1 eggs during 14.9 days , while virgin ones deposited 19.5 eggs within 9.8 days . Singly captivated males survived longer than those which were allowed to mate • while the reverse was recorded for females.

Key Words: Elasnuat platyedrae, Pectinophora gossypiella Biology Habits

M. A. RAKHA AND M.E. EL-NAGGAR
Plant Protection Research Institute, Agric . Res . Center, Dokki , Giza * Egypt .

ABSTRACT

Four soil stigmaeid species were recorded m Giza associated with soil fauna, Apostigmaeiss navicella Grandjean , A. aegypaacus Soliman & Gomaa, Sri gmae u.s triramous Soliman &Gomaa and S . africanas Soliman & Gomaa Biological studies on S. africaniss revealed that female life span averaged 39.8 days and deposited 44.5 eggs.

Key Words: Biocontrol , predecious mites, Stigmaeidae.

M.O. KOLAIB
Faculty of Agriculture , Menoufia University , Egypt

ABSTRACT

The tephritid Schistopterum r,we&iusi Beker feeds on the ovarioles of the wild plant Conyza dioscorides Dc. (Family Composizie) . The population fluctuation of the insect revealed that it h five peaks of abundance per year on this wild plant at Shebin El-Kom . The highest peaks occurred during July and September . Insect destniction to C &oscorides heads reached a maximum of 100%, However , -the desoctian to flowers within heads reached the maxima of 92 % and 89 % during 1989 and 1990, respectively . S moebizssi Beker seems to be specific in destroying C. dioscorides and may be used in future as a biological control agent against this wild plant in Egypt .

Key Words: Wild plant , Schistopterum moebiusi , Bioagent control.

ESMAT A. KARES
Biological Control Dept. Plant Protection Research Institute, ARC , Dokki . Giza , Egypt

ABSTRACT

The efficacy of two commercial products of Bacillus rhuringiensis , Bactospeine and Thuricide ; two different chemical insecticides, Cyanophos and Fenvalerate and their combinations on the 4th instar larvae of the pink boliworm Pecrinophore' gonssypiella was studied . The LC50 values were 3.65 x i0 I.U. for Bactospeine and 4.6 x i04 I.U. for Thuricide. Results indicate that Bactospeine was more efficient than Thuricide . The toxicity of Fenvalerate was higher than that of Cyanophos, where the LC50 values were 20.5 p.p.m for Fenvalerate and 35 p.p.m for Cyanophos Bactospeine and Thuricide when combined with LC10 of Cyanophos or Fenvalerate at low concentrations of 1.5 x 1O4 and Thuricide was combined with the synthetic pyrethroid Fenvalerate , the potentiation effect was more active ( + 49.54 and + 28.30 ) than when each of them was combined with the organophosphorus compund Cyanophos ( +46.66 and +24.52) . In general, Bactospeine was more active than Thuricide when it is combined with cyanophos or Fenvalerate . At high concentrations of Baccospeine and Thuricide (4.5 x 1O4, 6 x io and 7.4 x iO I.U. ) , combination with LC10 of Cyanophos or Fenvalerate generally produced additive effects.

Key Words: Bacillus rhuringiensis. Insecticides . Pectinophora gossypiella.

S.S. AWADALLA; M . E . RAGAB AND H.M. FATHY
Plant Protection Dept., Faculty of Agric., Mansoura University, Egypt .

ABSTRACT

The insects inhabiting sugar beet plants at Mansoura district included 18 injurious and 10 predatory species. Aphids. Cassida viuara (Vill.) Spodoptera lirroralis (Boisd.) Scoroobipalpa ocelLatella Boyed. and Pegomyia mixta Vill were the main insects infesting suger beet plants as indicated by their catch numbers . Coccinellids were the most abundant predatory species Numbers, ratios and population peaks of these insects were recorded. Prey / predator ratio between injurious and predatory insects reached 4.7- 4.8 during March, while the ratio reached a minimum of 1.1 aphids /1 predator in April. The differences between average population densities of aphids and that of their predators were insignificant but a postive correlation (r) between aphids and aphidophagous predators was recorded during the two growing seasons 1989/90 and 1990/91

Key Words: Suger beet, Insect pests, predators, Interaction,

S.M. AHMED, M.K. EL-KHISHIN. S.H. TAHER*, AND S.M. NAGUB*
Plant Protection Dept., Fac. Agric., Zagazig Univ.
* Plant Protection Research Institute, Dokki, Cairo , Egypt .

ABSTRACT

Newly hatched larvae of Pecrinophora gossypiella (S.) were reared on artificial diet contained gossypol and coumarin at different concentrations and at constant temperature of 27 ± I °C. and 80 ± 5 R.H. Treated larvae suffered mortality throughout the larval stage. Mortalities were concentration dependent. Coumarin was about 4.56 times more toxic than gossypol at LC 50 level. The two compounds decreased the rate of larval development. The two compounds caused reduction in larval and pupal weight and percentage of pupation. The reduction was proportional to concentration. Coumarin caused more malformation and elongation of pupal stage than gossypol. The two compounds reduced the percentage of emergency. Adults emerged from larvae reared on the diet containing the two compounds laid less number of eggs than control, and the frequency of mating was reduced. The tested compounds did not prove to be diapause inducers.

Key Words: Allelochemics , Gossypol , Coumarin , Biological aspects, Pectinophora gossypiella.

SAYED M. MOAWAD , SHAHIRA S. MAREI , MAMDOUH M. MATTER AND MOHAMED R. SALEH
Plant Protection Dept., National Research Centre , Cairo , Egypt .

ABSTRACT

The relative. pathogenicity of the microsporaidian Vairimorpha (Nosema) ephestiae to the second and fourth - instar larvae of Heliothis armigera (Hubner) was investigated . The results indicated that the larval mortality increased with the increase of the protozoan concentration in the diet Younger Iavae of the second instar were more susceptible than elder ones of the fourth instar . On the other hand, the latent effects, expressed as mortality or deformity of pupae and adults, were more pronounced among treated fourth instar larvae . The expression of CLD50 ( cumulative median lethal dose was used to calculate all deleterious effects of any protozoan concentration on all stages (larvae, pupae and adults) and averaged 7.2 x10 6 and 12.0 x 10 6 spores / ml for the second and the fourth larval instars , respectively . Larvae survived after infection showed an obvious reduction in pupal formation and adult emergence . The results revealed that V. ephestiae is an efficient biological agent against H. armigera.

Key Words: Protozoa, Vairimorpha (Nosema ) ephesriae , Helior his armigera

ADEL H- GHARIB
Plant Protection Dept ., Faculty of Agric ., Minia Univ. , Egypt

ABSTRACT

Three Bacillus sphaericus H-5a5b strains designated Ghar.l & 10 Ghar. 2 & 20 and Ghar . 3 & 30 were evaluated against Culex mosquitoes in simulated
and natural breeding sites . Broth suspensions of all strains at 1.5 x io to io6 cells I ml gave 89 - 97 % and 97 - 100 % mortality in field - collected C. pipiens larvae exposed outdoors ( 1.5 L buckets ) for 2 and 4 days respectively . Further testing of strain Ghar . 2 & 20 at io - 10 cells I ml against larval populations of the same species breeding in 25 L dishes showed
94.2 - 100 % control within 2 days . All strains at 2 x 1O4 - I0 cells I ml also exhibited excellent control ( 94 - in two days ) of a mixed population of C. wiiviuatus and C. anlennatus breeding in 1 - m2 plastic - bottomed ponds . Generally , larval control persisted for 7 - 14 days Application of strain Ghar. 2 & 20 at l0 cells I ml to cesspools and Ghar. 3 & 30 at lO cells I ml to a ditch produced 98.2 % and 94.5 % of C. pipiens larvae within 3 days, respectively. Primary powders of strains Ghar. 2 & 20 and Ghar . 3 & 30 at 12 - 24 mg I liter provided 92.2 - 100 % control of G. wuviliatus and C. aluennazus larvae breeding in 10 liter dishes.

Key Words: Bacillus sphaencus, local strains. Cider mosquitoes, field efficacy.

M.E. RAGAB
Plain Protection Dept., Fac of Agric., Mansoura Univ. , Mansoura , Egypt

ABSTRACT

The anthocorid predator Montandoniella moraguesi Puton. and the eulophid parasitoid Pleurotropis sp . are widely distributed among populations of Gynaikothrips Jicorwn Marchal, as specific control agents against this thrips that infests Ficus ,utida Thumb . in Egypt . The pest, predator and the parasitoid are continually present in Mansoura region during the year where the prey-predator ratios assured the important role of M. moraguesi as a controlling agent of the pest especially during January, February, March , July August and September The percentage of parasitism of Pleisrorropis sp . on host nymphs ranged from 1.6 to 95 % with a general annual rate of 35.18 % The parasitoid was able to reduce more than 50% of the host nymphs during January , February, March and August . The Larvae of Chrysoperla carnea Steph . are also associated with the immature stages of this thrips but with relatively low populations . The development and efficiency of C. carnea on diets of eggs or nymphs of G. ficorum were investigated under laboratory conditions.

Key Words: Ficus nitride Gynaikothrips ficorum. predators, parasitoids.

F.M. EL - AGAMY AND K.F. HAYNES *
* Entomology Dept., Fac. of Agric , Kentucky Univ., Lexington, U.S.A.
Department of Plant Protection , Faculty of Agric., Tanta Univ. Kafr l - Sheikh, Egypt.

ABSTRACT

The obstinacy behaviour of pea aphid, Acyrthosiphon piswn ( Harris) against synthetic alarm pheromone applied in combinazion with the malathion insecticide or the predator Nabis americoferiss (Carayon) was rested in green house studies . Aphid alarm pheromone, (E) - B- famesene did have a lithe synergistic effect when combined with malathion, but survival was decreased by 14.7 % .Aphids were not more accepted by the predator , N. americoferus in the presence of aphid alarm pheromone . The presence of alarm pheromone stimulated dispersal in the form of walking and significantly fewer aphids remained stationary at 5 and 15 minutes after the introduction of a rubber septum containing alarm pheromone than in the control groups.

Key Words: Insecta, Acyrthosiphon pisum. Alarm pheromone, Nabis americoferiss.

A.H. EL-HENEIDY, YAJ-IIA H.FAYAD AND MONA A.SHOEB
Dept .of Biological Control, Plant Protection Institute, ARC, Giza , Egypt

ABSTRACT

The present study was carried out to evaluate the effect of chemical treatments on aphids and their natural enemies in wheat fields during 1990-1991 planting season at Sohag Govemoraze (upper Egypt) Twos districts ; El - Maragha and Shandaweel were selected for this study Rate of aplds infestation , numbers of predators and percentage of parasitism were estimated weeldy aflover the season in the two locations El - Maragha field was treated three times with insecticides by laze February, while Shandaweel fields was treated only once early in the season . Obtained data showed that in spite of the frequent spray at El-Maragha field,aphid infestation lasted lenger than that of Shandaweel and continued relatively higher throu!hout the season Sharp decline in the number of predators (40-48%) and in the percentage of parasitism (66%) was observed after the insecticidal application, while a gradual increase in the number of predators was occurred towards the end of the season Shandaweel field Therefore an integrated aphid control programme in wheat fields considering the positive role of parasitoids and predators rather than dependance on chemical control should be developed.

Key Words: Wheat, Aphids, Parasitoids, Predators, Insecticides.

HEDAYA H. KARAM, AFILAM A. ALFAZAIRY, ELM. HEGAZI . AND LAMYA M. ABO-ABD-ALLAH
Faculty of Agriculture, Plant Protection Dept., Entomology Divi, University of Aleandria , Alex . Egypt .

ABSTRACT

The probability of survival to maturity of the parasitoid Microplitis rufwenrris in NPV-infected Spodoptera littoralis (Boisd.) larvae was greatly affected by the timing of eXposure of the host to the S. Liuoratis nuclear polyhedrosis virus (SLNPV) In general, survival fractions of the parasitoid increased as the period L>tween parasitization and virus-infection was increased. When host-infection was delayed by at least 2days following parasitization, the percentages â M.ruflvcntris cocoon formation and emerging of adults were not greatly irtluenced by virus-infection. However, the mean total developmental tinie (from egg to 4dult) of M.ruJIveniris increased as the period between oviposition and host virus infection increased, The parasitoid adult longevity did riot differ significantly when infection was delayed by at least 2 days after parasitizacort. On the contrary, longevity of parasitoids developed from host larvae infectea immediately following parasitization was less than that of the control.

Key Words: Macropilis rufiventris, Spodoptera littoralis, Nuclear polyhedrosis virus, Development, Longevity.

LAILA A. EL - BATRAN AND H.M FATHY
Plant Protection Dep., Faculty Of Agriculture , Mansoura University

ABSTRACT

The feeding capacity of C. carnea larvae on T.aurantii and C.hesperidum was investigated under laboratory conditions of 25°C ± 2 and 60-70 % R. H. It was found that the predating efficiency increased as the larvae grew older. Rate of prey consumption was highest on T.aurantii. The biomasses of carbohydrate, lipid and protein consumed by larvae were estimated. The results showed that a certain quantity of protein was consumed by the larva at each instar whatever the type of prey, while the quantity of the other two components depended on the prey type.

Key Words: Predators, Chrysoperla carnea, Biomass, Protein.

M.F.S. TAWFIK AND S.M. ABOL-ELA
Laboratory of Biological Control; Faculty of Agriculture; University of Cairo , Giza , Egypt

ABSTRACT

The fine structure of the anal vesicle in different larval instars of the braconid Apanteles glomezanss was studied aiming to shed light on its function. It appears that this organ, in the first larval instar, absorbs fat from the haemolymph of the host (caterpillars of Pieris brassicae) and at the same time may be excretory The specialized systems at this stage, are not yet functioning It is only during the second stage that these systems are working and consequently, the vesicle no more performs food ingestion and to a large extent excretion.

Key Words: Apanteles glomeratus L Pieris brassicae L ; vesicle ingestion, excretion , locomotion

A.M. HEKAL
Faculty of Agric., Am Shams University , Cairo , Egypt

ABSTRACT

Development and longevity of Chelonus sukazus Nees, an egg larval parasitoid of the pink bollworm, Pectinophora gossypiella ( Saund. ), were studied at different constant temperatures. Successful development occurred at all tested temperatures between 20 and 35 °C . The developmental period was negatively correlated with temperature ; the shortest period was 21.9 days at 35 °C Female longevity reached a maximum of 30 - 7 days at 27 °C.

Key Words: Chelonus sulcarus. Pecrinophora gossypiella, Development Longevity.

G. FEDIERE, A.A. TAHA, X. LERY, J. GIANNOTTI, J.L. ZEDDAM, A. MONSARRAT AND S. ABOL-ELA.
Entomovirology laboratory - ORSTOM - Faculty of Agriculture, Cairo University , Giza , Egypt .

ABSTRACT

A small RNA virus was isolated from larvae of the maize stem borer Sesamia cretica Lederer (Lepidoptera: Noctuidae) . Some properties of this virus (Maize Stem Borer Virus : MSBV ) have been studied. Electron microscopic observations of the purified suspention showed the presence of non-envelopped isometric viral particles. 30 nm in diameter. The viral genome was composed of RNA, the virus capsid contained three major proteins ( VP!, VP3, VP4) with molecular weights of 60 000, 45 000 and 28 000 as well as one minor (VP2) with molecular weight of 58 000 daltons . Immunodiffusion tests showed that MSBV was serologically unrelated to certain insect Picorna-like viruses. This new virus could be provisionally arranged among the unclassified small RNA viruses of invertebrates and represents a great interst as a biological control agent.

Key Words: Sesamia cretica . Noctuidae RNA virus. Biocontrol agent

EMAN B. MOURSY AND G.H. SEWIFY
Faculty of Agriculture Dept. of Economic Entomology. Cairo University

ABSTRACT

A decrease in concenation of otal ctude protein in hacsmolymçth was recorded in fingus infected Apkis craccivora Koch and Brcvkoryrw brassicat (L) compued to the minfecied ems . A. craccivora was more affected by the fungus; Verticillium lecasii (Zimm.) Viegas, infection than B. brassicae . Moreover, the quantity of free amino acids in the haemolymph of A. craccivora was significantly affected by the fungus infection AU amino acids of haemolymph except histidine and arginme were significantly reduced in the infected aphids.

Key Words: Entomopathogenic fungi, Verticillium lecanu, Aphis craccivora, Brevicoryne brassicae

A.M.A. IBRAHIM; K.T. AWADALLAH and MOUNIR D. ABDAILAH
Biological Control Laboratory, Faculty of Agriculture, Cairo University .

ABSTRACT

Chrysopids, especially Chrysoperla carnea Stephens, are efficient predators against different aphid species. Their effectiveness could be increased by providing supplementary diets. Three diets were used; i.e. yeast + Sugar + water, molasses and sucrose solutions. The former diet showed the best results; either in increasing chrysopids eggs and subsequently decreasing aphids counts or in its long lasting effect. The effect of molasses and sugar solutions ranked second and third category; with insignificant variations. It is recommended to use yeast + sugar-i- water, as a stimulant for C. carnea.

Key Words: Biological, Predators, Chrysopids species.

A.H.FOULY and A.M.MABROUK*
Dept. of Plant Protec., Faculty of Agric., Mansoura Univ.
* Dept. of Agric. Zoology and Nematology, Fac. of Agric., Cairo Univ. , Egypt .

ABSTRACT

Certain biological aspects of the predatory mite Amblyseius scut fed on Tdranychzss urticae nymphs were studied at 25,30 and 35°C correlated with 50,70 and 90% RH. Low humidity when accompanied with high temperature reduced egg viability. Also.developmental duration negatively correlated with temperature and relative humidity. Moreover, temperature and relative humidity as well as their interaction highly affected the feeding capacity of immature stages. Longevity of adult female decreased by rising teperature. Female mite consumed the greatest number of prey and produced the greatest amount of eggs at 3O°C.

Key Words: Temperatuire , Relative Humidity , Predatory mite , Amblyscius scutalis.

ALY H. RASMY
Plant Protection Dept., National Research Centre, Dokki, Cairo , Egypt .

ABSTRACT

The different avenues , strategies and potential exploitation for the employment of semiochemicais in pest management are discussed. These avenues are monitoring mass - trapping , disrupting mating of pests and improving the efficiency of conventional insecticides without damaging the environment . In some cases semiochemicals can enhance the reproduction and activities of predators. Although the use of such chemicais in some case.s,shows promise for controlling pests and minimizing the environmental impact of insecticides, their implement in pest management still requires further investigations.

Key Words: Semiochemicals pheromones Ailelochemics

A. R. HAMED AND FAWZIA A. HASSANEIN
Biological Control Res. Dept., Plant Protection Res. Inst., Dokki, Giza , Egypt .

ABSTRACT

A survey of natural enemies of scale insects, mealy bugs and white flies was conducted in different regions of Egypt during the period 1987 - 1990 . Twenty two parasitoid species and nine predators were recorded. Most of the recorded natural enemies belong to the families Aphelinidae, Encyrtidae.. Pteromalidae, Coccinellidae, Nitidulidae and Chrysopidae.

Key Words: Parasitoids, Hyperparasitoids, Predators, Sclae insects, Mealy bugs, white flies.