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Schroeder C Horner S Bürger N Engemann C Bange U Knoop EV Gabert J 《Berliner und Münchener tier?rztliche Wochenschrift》2012,125(7-8):290-296
The low sensitivity of the IBR-gE ELISA compared to other diagnostic ELISA tests for IBR is a major disadvantage of IBR control programmes based on IBR marker vaccination. Therefore the IBR-gE ELISA is not generally recommended for testing pooled or bulk milk samples.The aim of this study was to determine the performance of a commercially available kit for concentrating and purifying antibodies in milk in order to improve the sensitivity of detecting IBR-gE antibody positive cows from pooled and bulk milk samples. A single IBR-gE positive cow is likely to remain undetected in a pool of 49 negative milk samples without concentration. By contrast, the bulk milk concentration procedure improved sensitivity from 5.4% to 75.7% in a positive herd. Milk samples with a high or moderate positive signal are more likely to be detected after pool milk concentration compared to weak positive samples. Whereas a follow up study involving a monthly testing of bulk milk samples from three marker vaccinated IBR-gE negative herds over a period of seven months yielded negative results each month, bulk milk from a herd containing <5% IBR-gE positive cows always detected positive after concentration. Although the milk concentration procedure had no impact on specificity, it significantly enhanced the sensitivity of the detection of IBR-gE positive milk in pooled and bulk milk samples. After further evaluation this procedure could allow a cost efficient and reliable method of monitoring IBR marker-vaccinated herds for IBR-gE antibodies. 相似文献
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Michael Preisitsch Stefan E. Heiden Monika Beerbaum Timo H. J. Niedermeyer Marie Schneefeld Jennifer Herrmann Jana Kumpfmüller Andrea Thürmer Inga Neidhardt Christoph Wiesner Rolf Daniel Rolf Müller Franz-Christoph Bange Peter Schmieder Thomas Schweder Sabine Mundt 《Marine drugs》2016,14(1)
In this study, the influence of halide ions on [7.7]paracyclophane biosynthesis in the cyanobacterium Nostoc sp. CAVN2 was investigated. In contrast to KI and KF, supplementation of the culture medium with KCl or KBr resulted not only in an increase of growth but also in an up-regulation of carbamidocyclophane production. LC-MS analysis indicated the presence of chlorinated, brominated, but also non-halogenated derivatives. In addition to 22 known cylindrocyclophanes and carbamidocyclophanes, 27 putative congeners have been detected. Nine compounds, carbamidocyclophanes M−U, were isolated, and their structural elucidation by 1D and 2D NMR experiments in combination with HRMS and ECD analysis revealed that they are brominated analogues of chlorinated carbamidocyclophanes. Quantification of the carbamidocyclophanes showed that chloride is the preferably utilized halide, but incorporation is reduced in the presence of bromide. Evaluation of the antibacterial activity of 30 [7.7]paracyclophanes and related derivatives against selected pathogenic Gram-positive and Gram-negative bacteria exhibited remarkable effects especially against methicillin- and vancomycin-resistant staphylococci and Mycobacterium tuberculosis. For deeper insights into the mechanisms of biosynthesis, the carbamidocyclophane biosynthetic gene cluster in Nostoc sp. CAVN2 was studied. The gene putatively coding for the carbamoyltransferase has been identified. Based on bioinformatic analyses, a possible biosynthetic assembly is discussed. 相似文献
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Low Incident Light Combined with Partial Waterlogging Impairs Photosynthesis and Imposes a Yield Penalty in Cotton 
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下载免费PDF全文 U. Najeeb M. P. Bange B. J. Atwell D. K. Y. Tan 《Journal of Agronomy and Crop Science》2016,202(4):331-341
Through field studies, cotton responses to dual stresses – waterlogging and low light (shade) were investigated. The hypothesis was that shade would amplify yield losses in waterlogged (WL) cotton. Either early or late in the reproductive phase, the crop was WL (96 h and 120 h, in 2012–2013 and 2013–2014, respectively) and/or shaded (6 days or 9 days in 2012–2013 and 2013–2014, respectively). Waterlogging at early reproductive phase significantly reduced lint yield (17 % averaged across both years) of cotton, although shade‐induced yield losses (18 %) were only significant in 2013–2014. Shade significantly exacerbated yield losses only when the impact of waterlogging damage was modest (2013–2014). More intense waterlogging impaired lint yield independently of the light levels. Yield reductions in these experiments were the consequence of both accelerated fruit abscission and fewer fruiting nodes produced. Plants had lower leaf nitrogen levels and photosynthetic rates after waterlogging and/or shade treatments and produced fewer fruiting nodes. Although long‐term shade increased specific leaf area (30 %) and leaf N (20 %) immediately following 5 days of waterlogging, it did not restore shoot growth, node formation or lint yield because of suppressed photosynthetic performance (area basis) and carbohydrate supply. 相似文献
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Immature cotton fiber will negatively impact textile processing. Three field experiments were undertaken that applied chemical harvest aids to upland cotton (Gossypium hirsutum L.) crops at varying times with the intention of manipulating the maturity of bolls and fibers. The aim was to quantify the effects of these treatments on the textile performance of the harvested cotton and relate these differences to the status of the crop at the time of treatment application. Although earlier treatments produced less mature fiber that was lower in linear density, yarn and fabric strength was not affected. However less mature cotton from a cooler growing season produced stronger yarns (by 3 cN tex−1) and fabric (by 0.39 N (g m−2)−1) which was partly attributed to the smaller ribbon width of this fiber affecting more fiber packing density and inter-fiber friction. Yarns made from this immature cotton also contained more neps. Micronaire and linear density were equally well related, and more strongly related than maturity ratio, to dyed fabric color dimensions, which were greatly influenced by treatments. Percent immature bolls at the time of harvest aid application related well to changes in the degree of fabric blueness (R2 = 0.89). Knowing the status of a crop in the final stages of production will help cotton producers and the supply chain to predict some of the processing performance aspects of harvested fiber. 相似文献
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Ullah Najeeb Daniel K. Y. Tan Michael P. Bange 《Archives of Agronomy and Soil Science》2016,62(8):1136-1146
Increased ethylene biosynthesis in cotton tissues have been associated with accelerated fruit abscission and yield losses in waterlogged cotton. In a series of glasshouse and field experiments, we investigated the effect of various application rates (0, 50, 100 and 150 [active ingredient, ai] ha?1) and time (pre- and post-waterlogging) of an anti-ethylene agent, aminoethoxyvinylglycine (AVG) on the growth and yield of cotton. The glasshouse study suggested that AVG (100–150 g [ai] ha?1) applied 24 h prior to waterlogging can increase growth and fruit retention (FR) of waterlogged (WL) and non-waterlogged (NWL) cotton. The positive effects of AVG were further validated in two years of field studies, suggesting that AVG (125 g [ai] ha?1) applied at an early reproductive phase of cotton can significantly increase cotton yield under WL (13%, averaged over two years) and NWL (9%, averaged over two years) environments. Yield increase in AVG-treated cotton was associated with increased number of bolls, boll weight and FR. On the other hand, no further improvement in cotton yield under higher AVG concentration (150 g [ai] ha?1) indicated the saturation of AVG on ethylene inhibition. Thus, appropriate AVG concentration and application timing may help overcome waterlogging-induced yield losses in cotton production systems. 相似文献
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Cotton leaf nutrient concentrations in response to waterlogging under field conditions 总被引：1，自引：0，他引：1
Cotton is known to be poorly adapted to waterlogged conditions. When grown on soils with inherently low drainage rates, combined with the use of furrow irrigation and with summer dominant rainfall patterns, there is a significant risk of intermittent waterlogging. Good surface drainage is the most effective management option but when land-forming is poor or when substantial rain occurs soon after an irrigation application, significant yield loss can occur. Two field experiments were conducted in which cotton was subjected to waterlogging by extending the duration of furrow irrigation events. In order to assess the impact of waterlogging on plant nutrition, mineral nutrient concentrations in the youngest fully expanded leaves were measured repeatedly during the imposition of waterlogging, during recovery and through to the end of the growing season. Almost all nutrient concentrations were reduced by waterlogging but the extent and timing of recovery varied. A single early waterlogging event had a much greater impact (especially on N, P and K) than a single event late in development. Recovery from waterlogging appears to have been impaired during the period of rapid boll growth. During this period also, normal irrigation events caused transient reductions in some nutrients if the crop had been previously waterlogged. As with other studies on waterlogging, there was evidence that sodium concentration in leaves increased. While P and K concentrations were negatively associated with leaf sodium, there was no evidence that this relationship was altered by waterlogging.Management of nutrition after waterlogging has previously focused on the correction of leaf N and Fe concentrations. The wide range of nutrients that was affected in our experiments suggests that the value of correcting nutrients other than N needs to be explored. In addition, the results suggest that there is also a need to promote growth after waterlogging, rather than only correcting the nutrient concentration, to provide a larger reserve of key nutrients to meet reproductive demand. 相似文献
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The worldwide need to improve water use efficiency within irrigated agriculture has been recognised in response to environmental concerns and conflicts in resource use. Within the Australian cotton industry, the imperative to reduce water use and optimise irrigation management through the understanding of risk, using information generated by computerised decision aids was identified and subsequently developed into the HydroLOGIC irrigation management software. This paper summarises the attributes of the HydroLOGIC irrigation management software, with particular emphasis on functionality and its application to irrigation decisions within the Australian cotton industry. The software development process is documented to provide direction for future software application initiatives, with particular emphasis on a process of user feedback, evaluation and support requirements providing direction to software development. On-farm experiments throughout the development period allowed the validation of internal software logic, irrigator decision processes, and the OZCOT cotton growth model. The software demonstrated the ability to improve yield and water use efficiency by optimising strategic and tactical irrigation decisions in the Australian furrow irrigation cotton production system. In 7 of the 11 on-farm experiments conducted, the use of HydroLOGIC helped improve overall field water use efficiency by optimising the timing of irrigation events or by indicating further irrigations would not provide yield or maturity benefits. The paper also presents useful insights into the development of software targeted for irrigation utilising in-field measurements of soil water, crop growth and a crop growth simulation model. 相似文献
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