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.