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101.
BACKGROUND: Greenhouse whiteflies, Trialeurodes vaporariorum (Westwood), are notorious pests that, through the reduction of crop yields and excretion of honeydew, cause significant economic losses for sweet pepper (Capsicum annuum L.) growers. Chemical and biological controls are the two most common forms of whitefly management in greenhouses. Consequently, insecticide resistance and inadequate control have rejuvenated interest in alternative tactics. In the present study, whitefly responses to trap crops (eggplant and squash) and yellow sticky traps were compared in order to identify the most effective traps for dispersing and resident adults. RESULTS: Results indicated that yellow sticky traps were most effective at trapping adult whiteflies. Significantly more dispersing whiteflies were recorded on eggplant than on squash trap crops. None of the traps significantly reduced adult populations on the main crops (peppers) compared with the control. However, yellow sticky traps did significantly reduce oviposition on peppers. CONCLUSIONS: Adult whiteflies were most effectively trapped on yellow sticky traps followed by eggplant trap crops. Further study of whitefly trapping using visual cues may enhance trapping management. Specifically, research combining yellow sticky traps with other control strategies is recommended. Copyright © 2011 Society of Chemical Industry  相似文献   
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A sensitive liquid chromatographic (LC) method with UV detection was developed for the determination of residues of lidocaine (LID) and its major metabolite, monoethylglycinexylidide (MEGX), in elk velvet antler. The drugs were extracted from alkaline velvet antler homogenates, cleaned up on a C(18) solid-phase extraction cartridge, and separated on an Inertsil ODS-3 (3.0 x 250 mm, 5 microm) column using an isocratic mobile phase made up of 0.05 M phosphate buffer (pH 4.0)/acetonitrile (88:12, v/v) at a flow rate of 1.0 mL/min. The limits of quantification for LID and its major metabolite, MEGX, were 10 and 20 ng/g, respectively. The method was validated and used to measure the concentration of residues of LID and MEGX in elk velvet antlers harvested after either LID anesthesia or application of a drug-free control method (electro-anesthesia, EA). No LID or MEGX residues were detected in any of the antlers harvested after EA application. No MEGX residues were detected in any of the velvet antlers harvested after LID application, but residues of LID ranging in concentration from 68 to 4300 ng/g were detected in the three sections of the velvet antlers harvested after LID administration. LC-tandem mass spectrometry was used to confirm the presence of lidocaine detected in the velvet antlers.  相似文献   
104.
This study attempts to identify the soil properties controlling the fractionation of copper into various soil pools and determine the influence of pH and metal loading on soil-solution free copper activity (pCu2+). The pCu2+ was determined in 0.01 M CaCl2 soil extracts using a copper ion selective electrode. We analyzed a wide variety of soils: urban, agricultural and forest soils from the Province of Québec, New York State and Denmark. The pCu2+ ranged from 12.21 to 6.18. The relationships among pCu2+, total soil copper, total dissolved copper and soil pH are studied for their variability within and between sites as well as for the whole data set. Regression equations are presented for predicting soluble copper as a function of total soil copper and also for predicting pCu2+ as a function of total soil copper and soil pH.  相似文献   
105.
A commercial bullfrog (Rana castesbeiana) operation in south Georgia had multiple epizootics of systemic bacterial infections over a 3-year period, 1998-2000. A number of potential pathogens (Aeromonas hydrophila, Chryseobacterium (Flavobacterium) meningosepticum, Chryseobacterium (Flavobacterium) indolgenes, Edwardsiella tarda, Citrobacterfreundii, Pseudomonas spp., and (Streptococcus iniae) were isolated from various tissues. Clinically, frogs demonstrated acute onset of torticolis, stupor, and indifference to stimuli. Cutaneous hyperemia, subcutaneous and muscular hemorrhage, and peripheral edema were consistent gross findings. Histologically, clusters of lymphocytes, monocytes, and occasional acidophiles with scattered granulomas occurred in liver, kidney, and spleen. This is the first report of S. inae and C. meningosepticum as potential disease agents in R. castesbeiana. These findings suggest that a variety of bacteria may be associated with redleg and that culture results must be obtained for accurate diagnosis.  相似文献   
106.
A comparative study of the treatment of 306 severe, moderate, or mild cases of bovine endometritis was carried out over two calving seasons. The cases were treated with alfaprostol, or an intrauterine antibacterial preparation, or with a combination of both therapies. There was no significant difference between the efficacies of these treatments, and a single injection of alfaprostol was effective in 74 per cent of the cases treated. The effectiveness of the treatments was related to the degree of self-cure of the endometritis after parturition, the luteal activity at the time of treatment, and farm management factors affecting the health and condition of the calving cows.  相似文献   
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Barley stunt disorder in Scotland.   总被引:6,自引:5,他引:1  
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110.
The semisynthetic aminoglycoside amikacin is a potentially valuable antibiotic in broodmare practice due to its efficiency against Gram negative bacteria which have developed resistance to gentamicin. Each of 4 mares conceived when amikacin at 200 ug/ml in buffered extender was used in artificial insemination or as a prebreeding infusion. After intrauterine infusion of 2 g amikacin in 200 ml saline, 4 mares conceived to natural service or insemination with untreated semen after seven hours. In unbuffered saline solutions, amikacin (1 g/100 ml) and gentamicin (1 mg/ml) were spermicidal in vitro.  相似文献   
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