Mortalität des Kornkäfers,Sitophilus granarius,bei Begasung mit Methylbromid in Abhängigkeit von der relativen Luftfeuchte

the mortality of the grain weevil,Sitophilus granarius, treated with methyl bromide at 25° and 30°C is influenced by the relative humidity. The concentrationtime product for a mortality of 90% increases significantly with humidity.     

Einige Beobachtungen über die Flucht von adulten Lepidopteren aus den Netzen orbiteler Spinnen

Zusammenfassung Beobachtungen bei Zürich ergaben, daß Lepidopteren-Falter oft in der Lage sind, sich aus Spinnennetzen von Arten der Argiopidae und Tetragnathidae zu befreien. Lepidopteren machen nur einen sehr kleinen Teil der Nahrung dieser Spinnen aus. Diese Tatsache muß bei der Bewertung von Spinnen als Schädlingsfeinde mit berücksichtigt werden.

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Some observations on the escape of adult Lepidoptera from webs of orb-weaving spiders

Field studies near Zurich (Switzerland) have shown, that adult Lepidoptera often are able to escape from spider webs of the families Argiopidae and Tetragnathidae. In the food of these orb-weaving spiders Lepidoptera made up only a very small part. The capability of the lepidopterans to escape from spider webs seems to be of great ecological importance.

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Mit einer Tabelle

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Ausgeführt mit Unterstützung durch den schweizerischen Nationalfonds zur Förderung der Wissenschaftlichen Forschung.     

Zur Bekämpfung von Larven des Tabakkäfers (Lasioderma serricorne Fab.) durch Gefrieren von Rohtabak und Tabakfertigprodukten

Freezing of tobacco balls (Brasil, 90×50×50 cm.) and boxed cigars in a cold room at ?20°C was found to control the larvae of the cigarette beetle satisfactory. All test larvae in the center of balls and boxed cigars were killed at a temperature of ?12°C which was reached after 11 respectively 14,5 hours.     

Ein praxisnaher Versuch zur Ermittlung der Dauerwirkung von Bacillus thuringiensis Berliner gegen die Dörrobstmotte Plodia interpunctella Hbn in einem Getreideschüttbodenlager

In order to test, under warehouse conditions, the longterm effectiveness of THURICIDE® dust, containingBacillus thrungiensis var.kurstaki (=Serotype H_{3a, 3b}), with a viable spore count of 6 to 10 million per mg, the biopreparation was applied to rye, stored in bulk, on which larvae of the Indian Meal Moth (Plodia interpunctella Hbn.) were fed. From May to October, moth eggs were exposed monthly to rye dusted with 100 mg (320×10³ IU) resp. 150 mg (480×10³ IU) THURICIDE® dust per 100 g grain respectively. At a concentration of 100 mg 0.2% to 2.4% of the larvae, which hatched from the eggs in May, June and August, survived to the adult stage. No moths were observed in the experiments continued during September and October. At a cocentration of 150 mg, only in the experiments started in June and July 2.7% and 0.1% respectively of the eggs and larve survive to become adults. In the experiments of May, August, September and October, none were stated to have survived. The biopreparation-free control of May, June and July showed that about 75% of the eggs/larvae reached the adult stage, whereas, in August, September and October, untreated eggs and larvac reaching the adult stage amounted to 14% and 1% respectively. In reason of the combination of the efficiency ofBacillus thuringiensis and of the only small amount of surviving larvae due to the low temperatures during autumn and winter months, the surface application of THURICIDE® dust would be promising measure for combatting moth pests in bulk-stored grain.     

Rasterelektronenmikroskopische Untersuchungen an von Vorratsschädlingen angegriffenen Verpackungsfolien aus synthetischen Kunststoffen und abgewandelten Naturstoffen

Packaging foils made of cellulose actetate, cellophane, polyethylene, polypropylene, polystyrene, polyester, polyvinyl chloride, attacked byRhizopertha dominica F.,Stegobium paniceum L.,Tribolium castaneum Hbst. and larvae ofPlodia interpunctella Hbn. were examined with the scanning electron microscope (SEM). Because of the destruction marks made by the insects, it is possible to determine with the SEM the side of packaging material which has been attacked by the pests. Due to the shape and position of the mouthparts of the insects the gnawing marks are rather typical for the different species. By means of a standard of comparison it might be possible to determine the family and perhaps the genus or species of the insects involved. The influence of shape and size of the mouthparts as well as the position of the mandibles in relation to the anatomy and to the axis of the body on the gnawing ability of stored-product pests is discussed. The reasons for the insect resistance of packaging materials are discussed (smoothness of the surface, rigidity, thickness).     

Aus der Vorratsschutz-Arbeit des Pflanzenschutzamtes Berlin. Tierische Schädlinge in Nahrungs- und Genußmitteln der Großlagerhaltung und Bekämpfungsmaßnahmen in den Jahren 1980–1986

Zusammenfassung Es wird über das Auftreten von 25 Vorratsschädlingen, darunter 17 Käfer- und 3 Mottenarten, in den Lägern der Bevorratungsabteilung des Senators für Wirtschaft und Arbeit, der sonstigen Großlagerhaltung sowie in den Vorräten privater Haushalte berichtet. Die häufigsten Schädlinge in der Großlagerei waren Brotkäfer (Stegobium paniceum L.) und Speichermotten (Ephestia elutella Hbn.). Für den Vorratsschutz interessante Fälle und besondere Arten werden ausführlicher behandelt. Außerdem wird ein Überblick über die Entwesungs- und Entseuchungsarbeiten gegeben, bei denen neben den Begasungsmitteln mit den Wirkstoffen Methylbromid, Phosphorwasserstoff und Blausäure auch Vorratsschutzmittel auf der Grundlage von Dichlorvos, Pyrethrum und Piperonylbutoxid in verschiedenen Anteilen eingesetzt werden.

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Stored products protection activities of the Plant Protection Office Berlin. Pests of foodstuffs and pest-control in warehouses from 1980 to 1986

It is reported about the appearance of 25 stored-product pests, within 17 species of beetles and 2 species of moths in warehouses of the Bevorratungsabteilung des Senators für Wirtschaft und Arbeit as well as in the other warehouses and private households. The drugstore bettle (Stegobium paniceum L.) and the warehouse moth (Ephestia elutella Hbn.) were the most common pests. Cases of special interest and particular species are described in detail. Also is given a survey about the pest-controlling measures carried out with poisongas as methylbromide, phosphine and hydrocyanic acid and with insecticides on basis of dichlorvos, pyrethrum and piperonylbutoxide.

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Mit einer Abbildung und 3 Tabellen     

Einsparung von Herbiziden bei gleichzeitiger Erhöhung des Zuckergehaltes bei Zuckerrüben

The present trial was destined to find out whether it is possible to reduce the herbicides-amount of application by 50% i.e. on the one hand with normel water and on the other hand on a basis of Carborain-CO₂-water. The effects resulting from this in comparison with the full-application amount control, should be estimated. After the one year trial in summary one can say that in general the level of yield between half and full application amount did not vary substantially. Though the yield of each of the plots sprayed with CO₂-water were higher than the comparable normal water plots. Far extremer was the comparison of the sugar content. The sugar content of the reduced normal water plot was even below the one of the control. In comparison to that with the Carborain-water a higher sugar content by 5% relative was ashieved.     

Einsatz von Prallmaschinen zur Bekämpfung der MehlmotteEphestia kuehniella Zeller (Lepidoptera: Pyralidae) in Mehl und Grieß

Zusammenfassung Durch den Einsatz eines Doppelrotors konnte die Durchsatzleistung beim Prallvorgang von Mehlen von 7 t/h auf 12 t/h bei gleichzeitiger vollständiger Abtötung der Eier vonEphestia kuehniella gesteigert werden.Bei der Prallung von Grießen in Prallmaschinen kann durch Verringerung der Umlaufgeschwindigkeiten der Prallbolzen eine unerwünschte Verfeinerung des Produktes vermieden werden. Eine Abtötung von Mehlmotteneiern ist bei Leistungen von mindestens 12 t/h weiterhin gewährleistet.

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Use of impact machines to control the Mediterranean Flour MothEphestia kuehniella (Lepidoptera: Pyralidae) in flour and semolina

By using a double rotor system in impact machines for flour treatment the capacity can be increased from 7 t/h to 12 t/h and still showing 100% mortality of eggs from the Mediterranean Flour MothEphestia kuehniella.By semolina treatment in impact machines the velocity of the bolts can be reduced to insure that the granulation of the treated product is not influenced to an unacceptable degree. A 100% kill ofE. kuehniella eggs can be reached for a capacity of at least 12 t/h.

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Mit 3 Tabellen     

Untersuchungen über die Wirkung von Bacillus thuringiensis Berliner auf die Dörrobstmotte (Plodia interpunctella Hbn.)

For testing the prompt and long-term effectiveness of a THURICIDE-dust containingBacillus thuringiensis var.kurstaki, serotype 3a, 3b with a viable spore count of 6 to 10 million per mg and an insecticidal activity of 3,2×10³ international units (IU) per mg, the biopreparation was applied to rye on which larvae of the Indian Meal Moth (Plodia interpunctella Hbn.) were fed. A concentration of 20 mg (64×10³ IU) of dust in 100 g of grain caused in 82% mortality, and a six-fold higher concentration (120 mg, 384 × 10³ IU respectively) resulted in 99,0% mortality. The efficiency of the preparation was not reduced by storage for as long as 5 months in any five tests, which were at temperatures from 12°C to 28°C with 75% r.h. The larval stage of the surviving was prolonged by 3 to 4 weeks. Surviving moths, whose larvae were reared on grain to which the preparation was applied, were fertile and did not infest the following generation.