AbstractIn South-East Asia, cocoa production is dramatically affected by cocoa pod borer (CPB) infestations. As an alternative tool to chemical control, the efficacy of attract-and-kill strategy (CPB sex-pheromone as attractant and Delta trap without sticky liner sprayed with cypermethrin solution as killing station) was evaluated and compared with current standard CPB management approach as control treatment during two main cocoa harvest seasons in Malaysia (with 100 µg and 33.3 µg CPB-pheromone loading per station, respectively). In both seasons, attract-and-kill strategy was highly effective at reducing male flight activity (p?<?0.05) in attract-and-kill plots comparing with standard CPB management plots. For the percentage of CPB-infested pods, the attract-and-kill strategy (100 µg) was as good as the conventional pesticide spray applications of cypermethrin (p?=?0.083) in first season. However, it was significantly (p?=?0.021) reduced in the second season with lower pheromone loading (33.3 µg), indicating that this semiochemical based strategy is far superior to and more feasible than the currently applied conventional synthetic pesticide treatment and is therefore a good alternative in CPB integrated pest management. 相似文献
Summary Kraft and ethanol organosolv lignins from Picea abies and Fagus sylvatica were carboxymethylated with bromoacetic acid. Of the total hydroxyl groups in the lignins, 60–70% were carboxymethylated. The reaction led to an increase of the number-average molecular weights. The moisture adsorption of the carboxymethylated products is about one and a half as high as that of the original lignins. There are no remarkable differences between the solubilities of the treated and untreated products.The authors wish to express their appreciation to Mr. Dietrich Meier, Federal Research Organization for Forestry and Forest Products, Hamburg, Federal Republic of Germany, for preparation and donation of lignin samples 相似文献
Zusammenfassung Die in eigenen Versuchen ermittelten Minimum - Dosierungen von Toxaphen und Endrin bei der Flächenbehandlung gegen Feldmäuse (Microtus arvalis PALLAS) werden an Hand der von anderer Seite veröffentlichten Untersuchungen zur Toxizität der Wirkstoffe für Weidevieh diskutiert. Die vorliegenden Versuche mit Futter, das unmittelbar nach der Applikation der Wirkstoffe verabreicht wurde, lassen jedoch keine Rückschlüsse auf die Verhältnisse bei der Feldmaus-Flächenbegiftung zu. Denn bei der Durchführung dieses Verfahrens während der Vegetationsruhe werden die Wirkstoffe in der zwangsläufig gegebenen Wartezeit bis zur Wiederbeweidung abgebaut, so daß es kaum zur Bildung von bedenklichen Rückstandsmengen in Fleisch, Fett und Milch der Weidetiere kommen kann. Eine einmalige Flächenbehandlung gegen Feldmäuse auf Grünland mit den jetzt erreichten Minimal-Dosierungen, die eine weitere Annäherung an den insektiziden Bereich bedeuten, ist augenscheinlich in toxikologischer Hinsicht nicht anders zu bewerten als z. B. eine zweimalige Behandlung von Kulturpflanzen mit insektiziden Konzentrationen. 相似文献
To identify the perspectives of seed sowing for reforestation of degraded dry Afromontane savanna in exclosures in northern Ethiopia, seeds of a fleshy-fruited, secondary climax tree, Olea europaea ssp. cuspidata, were placed under two pioneer shrub species (Euclea racemosa and Acacia etbaica) and in open microhabitats. Seed removal and germination rates were examined. The effects of bird ingestion, manual pulp removal and mechanical endocarp treatments on germination rates were also studied.
Pulp removal promoted seed germination, in particular in seeds without endocarp manipulation. Seed removal, presumably by rodents, was concentrated in narrow strips along linear soil conservation structures, and not different between shrubs and open microhabitats. In the absence of water stress, humus types did not have a significant effect on germination rates. Under field conditions however, germination was higher under Euclea canopies. The observed facilitative effect of Euclea shrubs on germination may be attributed to moisture retention effects, related to the deep humus layer and canopy architecture, preventing desiccation and promoting imbibition of seeds. When readily available Olea seeds are not used for seedling production, direct sowing of seeds in the humus under dense Euclea shrubs could offer a cheap complement to planting of nursery-raised seedlings for forest restoration projects in recovering Afromontane savanna. 相似文献
To determine potential growth strategies for the German fresh potato market, production area, harvested quantities, producer prices and consumption values for the German potato market were examined using trend analysis. German potato harvests were stable over time due to improved growing techniques. Producer longterm prices stayed stable despite their periodic volatility. Overall production area and levels of fresh potato consumption are undergoing a sharp decline. Furthermore, there is a significant relation between total yield and producer prices as dependent variables. In order to compensate for the reduction in consumption, a framework was developed to change the commodity status of fresh potatoes into a differentiated product with new market potential. A consumer and product orientated market segmentation and analysis was applied to the fresh potato market to identify trends and future opportunities. Application of these new differentiated products will help stop the decline of fresh potato consumption by attracting new customers in urban and rural areas. In addition, these new markets are expected to reduce the producer price volatility. 相似文献
The objective of this study was to investigate the maternal protection of gruntlings derived from wild sows vaccinated orally against classical swine fever (CSF) using C-strain vaccine. Three vaccinated sows and one unvaccinated control sow were included. Challenge infection of the progeny was carried out either intranasally or by contact at the beginning of the third month of life (61-65 days post-natum). Whereas, two of three litters had maternal antibodies, the progeny of one vaccinated sow was seronegative at challenge. The progeny of the control sow, which was challenged by contact infection, developed moderate clinical signs except for one animal which became ill and died. Two gruntlings derived from the vaccinated sows also died of CSF, although one of them had a relatively high maternal antibody titre (128 ND(50)). The transient infection and partial virus shedding observed in a small number of gruntlings with maternal antibodies and the fact that one animal with maternal antibodies became ill and died confirm the incomplete maternal protection at this age. The reason for this incomplete protection is discussed. As none of the surviving gruntlings could be shown to carry CSFV or viral RNA at the end of the experiment (36 or 70 d.p.i.), it may be concluded that these animals do not represent a potential CSFV reservoir. 相似文献
Obesity is a heritable trait and a risk factor for many common diseases such as type 2 diabetes, heart disease, and hypertension. We used a dense whole-genome scan of DNA samples from the Framingham Heart Study participants to identify a common genetic variant near the INSIG2 gene associated with obesity. We have replicated the finding in four separate samples composed of individuals of Western European ancestry, African Americans, and children. The obesity-predisposing genotype is present in 10% of individuals. Our study suggests that common genetic polymorphisms are important determinants of obesity. 相似文献