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The efficacy of a new class of insecticide (chloronicotinyl) Mospilan 20 SP (a.?i. acetamiprid), compared with Lannate 90 SL (a.?i. methomyl) and Applaud WP 25 (a.?i. buprofezin), in glasshouse control of whitefly (Trialeurodes vaporariorum) on tomatoes, was investigated. All investigated insecticides significantly decreased the number of whitefly larvae, compared with untreated plots where population density grew during the trial. Based on statistical analysis, efficacy of all insecticides on whitefly larvae were in the same category. Some differences occurred 7 days after the third treatment. Deposited egg number was significantly different between checks and each insecticide plot. Efficacy of investigated insecticides, evaluated according to deposited egg number, was also good and in the same category.  相似文献   
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Although BACE1 (beta-site amyloid precursor protein-cleaving enzyme 1) is essential for the generation of amyloid-b peptide in Alzheimer's disease, its physiological function is unclear. We found that very high levels of BACE1 were expressed at time points when peripheral nerves become myelinated. Deficiency of BACE1 resulted in the accumulation of unprocessed neuregulin 1 (NRG1), an axonally expressed factor required for glial cell development and myelination. BACE1-/- mice displayed hypomyelination of peripheral nerves and aberrant axonal segregation of small-diameter afferent fibers, very similar to that seen in mice with mutations in type III NRG1 or Schwann cell-specific ErbB2 knockouts. Thus, BACE1 is required for myelination and correct bundling of axons by Schwann cells, probably through processing of type III NRG1.  相似文献   
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Four 9-month-old Simmental male calves were presented with a history of sudden death. The necropsy and microscopic findings allowed a diagnosis of enteritis and severe intraluminal hemorrhage with blood clots in the jejunum, suggestive of jejunal hemorrhage syndrome.  相似文献   
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The results of a preliminary antifungal screening of the methanol extracts and the major anthraquinone aglycones, alizarin and emodin, of Rubia tinctorum and Rhamnus frangula in comparison with the antifungal activity of the anthraquinone-containing lichen Caloplaca cerina and its main secondary metabolite parietin are reported.  相似文献   
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Leptinotarsa decemlineata (Say), the Colorado potato beetle (potato beetle), is the most destructive potato pest in Serbia. Up to four pesticide treatments are necessary for its control. Insecticide resistance of the potato beetle in Serbia is well-investigated and documented, especially to organophosphates and carbamates. Toxicity of chlorpyriphos (organophosphates) and carbosulfan (carbamates) was investigated by topical application, using adults of the first generation from nine field populations. Adults of all populations possessed a certain level of resistance to both insecticides, with very low regression slopes (0.50–1.09 for chlorpyriphos and 0.57–0.85 for carbosulfan). Resistance ratios for chlorpyriphos ranged from 1.0 to 109.7 and from 1.0 to 52.8 for carbosulfan. There was no correlation between resistance to chlorpyriphos and carbosulfan. The key modes of resistance to organophosphates and carbamates are metabolism [overproduction of aliesterase (ALiE), a carboxylesterase] and altering the target site of acetylcholine esterase (AChE). Biochemical research of potato beetle resistance to organophosphates and carbamates, based on activity of ALiE and AChE, proved that the key mode of resistance to organophosphates was modification of ALiE and AChE to carbamates. Our results correspond to this research concerning the lack of correlation between resistances to these two insecticides. A certain level of resistance of the potato beetle to organophosphates and carbamates is widespread in Serbia. Different modes of resistance suggest the possibilities of control of this pest, such as choice of insecticide and insecticide rotation, wherever possible.  相似文献   
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Supplementing the diet of Coeloides scolyticida, Dendrosoter protuberans and Ecphylus silesiacus (Hymenoptera: Braconidae) with Parker's diet and the nectars of melliferous plants: Daucus carota L., Sinapis alba L. and Stachys recta L. had a significant effect on longevity, reproduction, developmental rate, and parasitizing of Scolytus scolytus (Fab.), Scolytus multistriatus (Marsh.) and Scolytus pygmaeus (Fab.) (Coleoptera: Scolytidae). These values were considerably lower for wasps fed with the nectar of Sinapis arvensis L. and Trifolium repens L. and the lowest for those without dietary additives. Parker's diet had the most significant effect on the parasitoids and parasitizing of the bark beetles. Nectar of S. recta and S. alba proved most suitable for C. scolyticida and D. protuberans, while E. silesiacus using the nectar from D. carota flower significantly increased parasitizing of S. pygmaeus. T. repens flowers were not a suitable additive for the diet of parasitoids. The parasitoids without additives in their diet had shorter lives, shorter development, and were less effective in reducing host numbers. E. silesiacus wasps had the longest development, and C. scolyticida the shortest. Generally, the parasitoids of the second generation had a slightly prolonged development (1–2 days).  相似文献   
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Abstract

Three thermal power plants in Serbia, Croatia and Bosnia of the Western Balkan region were expected to be metal polluting sources, and this study was performed to investigate the bioavailability and chemical speciation of trace metals in soils and soil water extracts, respectively. Surface (0–15 cm) soil samples along with maize and grass samples were collected at a gradient from the pollution source. The chemical speciation of metals was conducted using the Windereme Humic Aqueous Model (WHAM)/Model VI for water, whereas the Diffusion Gradient in Thin Films (DGT) technique was used to estimate plant availability. The chemical speciation indicated that more than 99% of all four metals in soil water extracts were complexed to fulvic acid. This is connected to relatively high soil pH (> 6.5) and high contents of soil organic matter in these soils. The accumulation of trace metals by DGT was not correlated to plant uptake. This is connected to the very low partitioning of free ions in solution, but also to the low variation in metal solubility and metal concentration in plant tissue between sites. In spite of active thermal power plants located in the areas, hardly any differences in concentration of soil metals between sites were seen and the partition of metals in soil waters was insignificant. The latter indicates that these soils have a large metal-retaining capacity. The only significant soil chemical variable affecting the variation in metal solubility was the soil pH. In a time with large infrastructure and industrial expansion in these areas, this investigation indicates the importance of protecting these high-quality soils from industrial use and degradation. High industrial activity has so far had insignificant effect on soil quality with respect to bioavailability of trace metals in these soils.  相似文献   
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