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F. A. Hakkaart Gusta Hartel 《European journal of plant pathology / European Foundation for Plant Pathology》1979,85(2):39-46
On the older leaves ofPelargonium zonale chlorotic rings and flecks are common, especially during spring and fall. From such plants an isometric virus can be isolated that causes local lesions on the leaves ofChenopodium quinoa. An attempt was made to produce symptomless plants, reacting negatively onC. quinoa. Meristem tips on a basal medium supplemented with α-naphthalene acetic acid and coconut milk produced abundant callus, but no plantlets. However, on media containing low concentrations of indole acetic acid and kinetin or benzyl adenine, some plants were produced that fulfilled the above requirements. Those selected on horticultural properties, are considered as valuable mother plants. Of twenty-one cultivars such plants were obtained. They may prove an important contribution to the improvement of theP. zonale industry in the Netherlands. 相似文献
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The effect of cooling rate on the crystallization behavior of mixes of high-melting milk fat fraction (HMF) and sunflower oil (SFO) was studied by following nucleation with laser-polarized turbidimetry. The initial crystals were photographed, and their thermal and polymorphic behaviors, as well as chemical composition, were investigated by calorimetry, X-ray diffraction, and capillary gas chromatography. Activation energies of nucleation were calculated using the Fisher-Turnbull equation. Despite small differences in Mettler dropping points for different ratios of SFO to HMF, induction times were significantly different between samples and were shorter at a slow cooling rate for the same supercooling. Rapidly cooled samples required more time at crystallization temperature to crystallize than slowly cooled samples because molecular organization prior to nuclei formation took place under different conditions. Regardless of cooling rate or composition, all crystals were in the beta' polymorph. However, morphology, thermal behavior, and chemical composition showed differences with cooling rate. Activation free energies of nucleation were of the same order of magnitude as those published for hydrogenated SFO. 相似文献
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The immersible culture medium MICUR-BT used in human medicine for the detection of antimicrobial substances in the urine was tested for its suitability in pigs. In in-vitro tests, 15 pure antibiotic substances, 2 pure substance mixtures as well as 5 veterinary injection preparations with no direct antimicrobial effect were checked. The agar perforation test was used as a reference procedure. In a total of 65 pigs the detectability of 9 pure antibiotic and chemotherapeutic agents, 2 pure substance mixtures as well as 5 veterinary drugs with no direct antimicrobial effect was tested after oral or parenteral application. In the in-vivo tests the MICUR-BT test turned out to be more reliable than the agar perforation test. In 76.9% of the untreated pigs below 30 kg b.w. the MICUR-BT-test showed an antimicrobial effect. Such effects were reduced by 38.3% in the reference procedure. 相似文献
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Differences in the progress of the biopesticide revolution between the EU and other major crop‐growing regions 
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下载免费PDF全文 Adalbert Balog Tibor Hartel Hugh D Loxdale Kenneth Wilson 《Pest management science》2017,73(11):2203-2208
The five‐year value in the compound annual growth rate of the biopesticides sector is predicted to be 16% by 2017 and to produce a global market worth $US 10 billion. Despite this, several impediments occur within the EU that negatively affect biopesticide research and innovation. At present, there are fewer biopesticide‐active substances registered in the EU compared with the United States, India, Brazil and China. The relatively low level of biopesticide research in the EU (6880 ISI papers) versus the United States (18 839), India (9501) and China (7875) relates to the greater complexity of EU‐based biopesticide regulations compared with these other countries. In this light, it is worth noting that tensions may exist between regulators that emphasise the beneficial nature of biopesticides in environmentally friendly crop management and those that adopt a more technologically based approach dependent on a chemical‐pesticide‐driven model. Compared with the other aforementioned countries, far fewer biopesticide products are available in the EU market, mainly as a direct result of the severe regulatory factors present there. The extent to which this trend will continue depends largely on a range of interacting political and/or regulatory decisions that influence environmentally friendly agricultural industries. © 2017 Society of Chemical Industry 相似文献
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Plieninger Tobias Torralba Mario Hartel Tibor Fagerholm Nora 《Landscape Ecology》2019,34(7):1565-1581
Context
Around 30% of European agricultural landscapes are classified as high nature value (HNV) farmlands. Current policies emphasize the multifunctionality of these landscapes, but little is known about the positive and negative associations of multiple ecosystem services within HNV farmland.
ObjectivesThis study aims to identify perceived ecosystem services synergies, trade-offs, and bundles in agricultural landscapes of HNV from a socio-cultural perspective.
MethodsWe performed a participatory mapping survey of 10 ecosystem services categories among 2301 rural residents in 13 European sites. We analyzed bivariate synergies and trade-offs between perceived ecosystem services through nonparametric correlation analyses. Spatial bundles of perceived ecosystem services were identified through hierarchical cluster analysis. Multinomial logit models were used to assess the influence of land cover on generating associations of ecosystem services.
ResultsWe find two strong and 16 moderate synergies of perceived ecosystem services (out of 46 possible ecosystem services pairs), mainly among different cultural ecosystem services. We do not reveal moderate or strong trade-offs. We identify five spatial bundles of ecosystem services, termed “Ecosystem services coldspots”, “Wild harvesting ranges”, “Nature areas”, “Recreational spaces”, and “Ecosystem services hotspots”. Of all land-cover co-variates, natural areas, urban areas, and roads have the strongest explanatory power.
ConclusionsOur study complements prevailing biophysical and economic analyses of ecosystem services synergies, trade-offs and bundles by a spatially explicit, socio-cultural perspective. We conclude that socio-cultural mapping of ecosystem services is useful for understanding the perceived multifunctionality of a landscape.
相似文献7.
For the purpose of detecting the synthesis of zinc metalloenzymes after zinc supplementation in an experiment using rats the animals were first depleted for 15 days and subsequently injected a labelled zinc salt solution (65Zn-ZnCl2) in a dosis of 0.4 mg (in terms of Zn) and with an activity of 3.0 muCi/100microliter. After a 5-day depletion period, the activity of the metallo-enzymes alkaline phosphatase in plasma and in the femur and carboxy-peptidase A and B in the pancreatic gland was found to rise at the same rate as the 65Zn-measuring rate in plasma, femur and pancreatic gland. By calculating correlations this interdependence was demonstrated. Thus the highly significant correlation coefficients prove for these metalloenzymes that a synthesis with the injected zinc salt has taken place whilst for carbo-anhydrase in blood this evidence was not furnished. As the zinc dosis is not exclusively used for the enzyme synthesis, but additional 65Zn is incorporated into the individual organs, it does not appear to be possible to draw conclusions from the 65 Zn-measuring rate in the individual organs on the intermediary availability. 相似文献
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G. Moreno S. Aviron S. Berg J. Crous-Duran A. Franca S. García de Jalón T. Hartel J. Mirck A. Pantera J. H. N. Palma J. A. Paulo G. A. Re F. Sanna C. Thenail A. Varga V. Viaud P. J. Burgess 《Agroforestry Systems》2018,92(4):877-891
Land use systems that integrate woody vegetation with livestock and/or crops and are recognised for their biodiversity and cultural importance can be termed high nature and cultural value (HNCV) agroforestry. In this review, based on the literature and stakeholder knowledge, we describe the structure, components and management practices of ten contrasting HNCV agroforestry systems distributed across five European bioclimatic regions. We also compile and categorize the ecosystem services provided by these agroforestry systems, following the Common International Classification of Ecosystem Services. HNCV agroforestry in Europe generally enhances biodiversity and regulating ecosystem services relative to conventional agriculture and forestry. These systems can reduce fire risk, compared to conventional forestry, and can increase carbon sequestration, moderate the microclimate, and reduce soil erosion and nutrient leaching compared to conventional agriculture. However, some of the evidence is location specific and a better geographical coverage is needed to generalize patterns at broader scales. Although some traditional practices and products have been abandoned, many of the studied systems continue to provide multiple woody and non-woody plant products and high-quality food from livestock and game. Some of the cultural value of these systems can also be captured through tourism and local events. However there remains a continual challenge for farmers, landowners and society to fully translate the positive social and environmental impacts of HNCV agroforestry into market prices for the products and services. 相似文献
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Yellowwood (Cladrastis kentukea) grows in small, widely scattered populations in the wild, but is also a popular ornamental tree that thrives when planted in urban areas outside its natural range. Since the small native populations of yellowwood in several states are considered at risk of extirpation, the cultivated population could serve as an ex situ repository of yellowwood genetic diversity that could be used to restore lost local populations of the species. The potential value of cultivated yellowwood for conservation depends on the genetic diversity among cultivated trees compared to natural populations. Using nuclear microsatellite markers, we genotyped 180 yellowwoods from natural populations in Indiana, Missouri, Arkansas, and Kentucky, along with 61 trees from urban parks and landscapes in Indiana, Ohio, and Missouri. We found that, even when statistics were adjusted based on population size, the urban “population” had higher genetic diversity than any of the wild populations sampled, indicating that commercially-grown yellowwood is most likely a mixture of genotypes from isolated wild populations. We observed strong genetic differentiation among wild populations, and evidence for inbreeding in at least one of the wild populations. 相似文献