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81.
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.  相似文献   
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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).  相似文献   
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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.
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.


Mit einer Abbildung und 3 Tabellen  相似文献   
87.
Seasonal fluxes of CO2 from soil and the contribution of autotrophic (root + mycorrhizal) to total soil respiration (SR) were estimated for a mixed stand of European beech (Fagus sylvatica) and Norway spruce (Picea abies) in Central Europe. Mature trees of each species were girdled in August 2002 to eliminate carbohydrate allocation to roots. SR was measured at distances of 0.5, 1.0, and 1.5/2.0 m from the bole of each tree at 1–2 weeks intervals throughout the fall of 2002 and monthly during the spring and summer of 2003. The contribution of roots and mycorrhizae to total SR was estimated by the decrease in SR compared to ungirdled control trees to account for seasonal patterns evident in controls. SR decreased with soil temperature in the fall 2002 and increased again in 2003 as soil warmed. During most of the study period, SR was strongly related to soil temperature. During the dry summer of 2003, however, SR appeared to be uncoupled from temperature and was strongly related to soil water content (SWC). Mean rates of SR in beech and spruce control plots as well as root densities did not show a clear pattern with distance from the bole. SR decreased to levels below controls in beech within a few days after girdling, whereas spruce did not show a significant decrease until October 2002, 6 weeks after girdling. In both beech and spruce, decreased SR in response to girdling was greatest closest to the bole, possibly reflecting increased mycorrhizal activity close to the bole. Autotrophic respiration was estimated in beech to be as much as 50% of the total SR in the stand. The contribution of autotrophic respiration was less certain for spruce, although close to the bole, the autotrophic fraction may contribute to total SR as much as in beech. The large fraction of autotrophic respiration in total SR requires better understanding of tree level stresses that affect carbon allocation below ground.  相似文献   
88.
It is predicted that dryland salinity will affect up to 17 Mha of the Australian landscape by 2050, and therefore, monitoring the health of tree plantings and remnant native vegetation in saline areas is increasingly important. Casuarina glauca Sieber ex Spreng. has considerable salinity tolerance and is commonly planted in areas with a shallow, saline water table. To evaluate the potential of using the nitrogenous composition of xylem sap to assess salinity stress in C. glauca, the responses of trees grown with various soil salinities in a greenhouse were compared with those of trees growing in field plots with different water table depths and groundwater salinities. In the greenhouse, increasing soil salinity led to increased allocation of nitrogen (N) to proline and arginine in both stem and root xylem sap, with coincident decreases in citrulline and asparagine. Although the field plots were ranked as increasingly saline-based on ground water salinity and depth-only the allocation of N to citrulline differed significantly between the field plots. Within each plot, temporal variation in the composition of the xylem sap was related to rainfall, rainfall infiltration and soil salinity. Periods of low rainfall and infiltration and higher soil salinity corresponded with increased allocation of N to proline and arginine in the xylem sap. The allocation of N to citrulline and asparagine increased following rainfall events where rain was calculated to have infiltrated sufficiently to decrease soil salinity. The relationship between nitrogenous composition of the xylem sap of C. glauca and soil salinity indicates that the analysis of xylem sap is an effective method for assessing changes in salinity stress in trees at a particular site over time. However, the composition of the xylem sap proved less useful as a comparative index of salinity stress in trees growing at different sites.  相似文献   
89.
Zusammenfassung Nach einem kurzen Überblick über die gesetzlichen Grundlagen für die Durchführung der Pflanzenbeschau wird über die Ergebnisse der Kontrollmaßnahmen bei der Einfuhr von Pflanzenerzeugnissen (Getreide) nach Berlin (West) berichtet. Von 1980 bis 1985 wurden insgesamt mehr als 700 000 Tonnen Weizen, Braugerste, Roggen, Hafer, Sonnenblumenkerne, Hirse und Erdnüsse aus 12 europäischen, amerikanischen und afrikanischen Ländern eingeführt, davon mehr als 99% allein aus der DDR.Die Importe aus der DDR waren im Durchschnitt zu knapp 1% mit Vorratsschädlingen befallen, und zwar mit dem Reiskäfer (Sitophilus oryzae L.), dem Gemeinen Kornkäfer (Sitophilus granarius L.), Leistenkopfplattkäfern (Cryptolestes spp.), dem Amerikanischen Reismehlkäfer (Tribolium confusum Duv.) und dem Rotbraunen Reismehlkäfer (Tribolium castaneum Hbst.).
Stored products activities of the plant protection office Berlin. The inspection of imported stored products from 1980 to 1985
A brief survey is given about the legal basis for the inspection of stored products (cereals) imported to Berlin (West). This follows a report about the results of those controls. From 1980 to 1985 more than 700,000 tons of wheat, barley, reye, oats, sunflower seeds, millet and peanuts were imported from 12 European, American and African countries, more than 99% of them from the GDR.On average about 1% of the imports from the GDR were infested by stored product pests; there were rice weevil (Sitophilus oryzae L.), grain weevil (Sitophilus granarius L.), grain beetles (Cryptolestes spp.), confused flour beetle (Tribolium confusum Duv.) and red flour beetle (Tribolium castaneum Hbst.).


Mit 2 Abbildungen und 3 Tabellen  相似文献   
90.
The effects of weaning on beef calves of different ages were investigated. Forty male and 40 female calves were either weaned at 6 (W6, n = 40) or 8 (W8, n = 40) months of age. The vocalization activity and behaviors (feeding, lying and standing/walking) were observed during the first 3 days following weaning. Body weight was recorded at 6 and 8 months and 2 weeks following weaning. W6 animals vocalized more often than W8 calves and females more than males on day 1 (P < 0.05). The vocalization activity decreased at a higher rate in W8 than in W6 from days 1 to 3. On day 2, W6 calves spent less time lying and more standing/walking than W8 calves (P < 0.05). The behaviors did not differ between males and females. The average daily gain after weaning did not differ between weaning ages (P > 0.05), but W8 calves gained more from 6 to 8 months of age. In conclusion, weaning distress was more pronounced in W6 than in W8 calves. W8 calves also had a superior growth performance during 6 to 8 months of age. The effect of the calves' sex was less pronounced. Therefore, it is recommended to wean beef calves later than 6 months of age.  相似文献   
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