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341.
Ing. Dr. Octavianus Farský 《Journal of pest science》1938,14(6):65-67
Ohne Zusammenfassung
Mit 3 Abbildungen. 相似文献
342.
343.
Enhanced phytoextraction of heavy metals using chelating agents and agricultural crops is widely discussed as a remediation technique for agricultural soils contaminated with low mobile heavy metals. In this study, phytoextraction efficiency of Zea mays after single and split applications of EDTA was tested on the laboratory and the field scale. EDTA effectively increased the mobility of target heavy metals (Pb and Cd) in the soil solution. Split applications provided generally lower water-soluble levels of Pb and Cd both in the pot and the field experiment. Therefore, the risk of groundwater contamination may be reduced after split applications. Higher Pb and Cd mobilisation after single applications increased plant stress, phytotoxicity and reduced plant dry above-ground biomass production compared to corresponding split doses. Single doses enhanced plant uptake of Pb and Cd and the phytoremediation efficiency compared to corresponding split doses. Results of plant dry above-ground biomass and heavy metal uptake obtained from the pot experiment could be to some extent verified in the field experiment. Plant uptake of Pb and Cd was lower and biomass production dropped after EDTA additions in the field experiment. Remediation factors in the field experiment were in general significantly lower than in the pot experiment mainly due to the much higher mass of soil per plant under field conditions. This highlights the limitations when going from the lab to the field scale. The low phytoremediation efficiency in the field and the mobilisation of high amounts of Pb and Cd down the soil profile may make the use of EDTA and Z. mays not suitable for the remediation of severely heavy metal contaminated soils in a reasonable time frame and may result in substantial groundwater pollution under used crop management. 相似文献
344.
Eva Chumanová Dušan Romportl Ludmila Havrdová Daniel Zahradník Vítězslava Pešková Karel Černý 《Scandinavian Journal of Forest Research》2019,34(4):254-266
Ash dieback, caused by the ascomycete fungus Hymenoscyphus fraxineus, has been rapidly expanding across Europe during the last two decades, posing a considerable threat to native ash populations. In this study, we applied regression-based models trained by field data, in conjunction with geographic information systems, to produce spatial predictions of ash dieback severity and environmental suitability for the disease in Czech forests. A model of actual ash dieback severity relates disease extent to silvicultural and environmental characteristics of forest stands and their neighbourhood, while a model of environmental suitability for the disease quantifies the relative susceptibility of sites to the disease, independent of the current silvicultural characteristics. The final predictive maps suggested that fertile lowlands and humid areas bordering Poland and Slovakia were the most endangered regions. Areas at the lowest risk of damage were concentrated in dry areas and in highland and mountain areas in the western part of the country, usually with poor soils on acid bedrock. Predictions of actual disease severity are an effective tool for guiding the current management of infested stands whereas predicting environmental suitability is useful for making long-term strategic decisions, e.g. identifying areas where future ash regeneration and cultivation may be unsuccessful. 相似文献
345.
Rosemarie Tedeschi Pavel Lauterer Lorenzo Brusetti Federica Tota Alberto Alma 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(3):301-310
Hawthorn (Crataegus monogyna) is one of the natural hosts of Cacopsylla melanoneura, the acknowledged vector of ‘Candidatus Phytoplasma mali’, the causal agent of Apple Proliferation disease, a serious and growing problem for apple production in
Europe, particularly in northern Italy. Wild plants could be important sources of both insects and phytoplasmas, but their
role in the epidemiology of phytoplasma diseases and their insect vectors has never been thoroughly examined. Cacopsylla melanoneura’s primary host is hawthorn, a plant closely related to apple which often grows wild near orchards. Other psyllid species
feed on hawthorn, but no data are available on their possible role as phytoplasma vectors. We investigated the hawthorn’s
psyllid fauna in northwestern Italy using yellow sticky traps, beat trays, and molecular analyses from 2003–2005, to study
the relationship between hawthorn, the phytoplasma and the insect vector. Population dynamics were monitored, and insects
and hawthorn samples were analysed by polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and
DNA sequencing for the presence of phytoplasmas. Cacopsylla melanoneura was the dominant psyllid species, followed by C. peregrina, C. affinis and C. crataegi. PCR and RFLP analyses revealed the presence of different fruit tree phytoplasmas in hawthorn plants, and in all four psyllid
species. 相似文献
346.
Aleš Mráček Marián Lehocký Petr Smolka Ondřej Grulich Vladimír Velebný 《Fibers and Polymers》2010,11(8):1106-1110
This article describes the novel possibility of the polyester (polyethylene terephthalate) surface modification by plasma
treatment. Moreover, this modified polyester could be component for the composite material (with hyaluronic acid) used in
the wound healing. In this study, the experimental methods: FT-IR spectroscopy, the contact angle measurement, X-ray photoelectron
spectroscopy and scanning electron microscopy were used for the surface modified polyester characterisation. 相似文献
347.
Jiří Skuhrovec Miloslav Zouhar Marie Maňasová Pavel Nový Matěj Božik 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(6):489-495
Purpose: Plant-derived essential oils and their encapsulations have recently received increasing interest as an alternative to synthetic biopesticides suitable for integrated pest management and organic farming. In this study, combinations of essential oils (EO) from Rosmarinus officinalis with Cymbopogon citratus and Pelargonium graveolens with Thymus vulgaris in two formulations including encapsulate were tested for their potential for wheat protection against adults and larvae of Oulema melanopus (L.).Materials and methods: The chemical composition of the essential oils was analyzed by gas chromatography-mass spectrometry (GC-MS). Testing of insecticidal activity of the evaluated substances was conducted with 2.5?ml of tested combinations of EOs sprayed on the paper. Ten adults or larvae of O. melanopus were placed into a vessel. Control of mortality of O. melanopus specimens was assessed after 24?h after establishment of the experiment.Results and conclusions: Tarsal contact toxicity assay showed the effectiveness of EO in concentration against O. melanopus larvae and adults in both formulations (essential oil and encapsulation) causing 100% mortality within 24?h. These results indicate the great potential of these essential oils and their encapsulations for future use in crop protection against insect pests. 相似文献
348.
Pavel Matušinsky Ivana Svačinová Akvilė Jonavičienė Ludvík Tvarůžek 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):199-209
Trichoderma aggressivum is an aggressive contaminant mould in the cultivation of Agaricus bisporus leading to severe reductions in mushroom yields. Production of fully colonised A. bisporus substrate in Europe is commonly carried out in large tunnels (Phase III), after which the substrate undergoes several bulk handling (mixing) operations before ending up on shelves in mushroom growing facilities. The work presented here studied the effect of Trichoderma aggressivum inoculum, substrate mixing and supplementation on Agaricus bisporus yields and evaluated four methods to detect T. aggressivum in bulk handled substrate. Inoculum dilution level was shown to correlate well with mushroom yield (P < 0.0001) with reductions of 2–6 % at the most dilute level (10?4) and 60–100 % at the most concentrated level (10?1), depending on the experiment. Supplementation, with or without T. aggressivum, had no significant effect on mushroom yield (P ≥ 0.85) but a high degree of substrate mixing was shown to significantly increase (P < 0.0001) T. aggressivum-associated crop losses. Four T. aggressivum detection methods were evaluated and a quantitative polymerase chain reaction (qPCR) method gave the most consistent and least variable results. Cycle threshold (CT) values ranged from 24 to 40, depending on the experiment and the inoculum dilution level, and false negatives (CT = 40) were reported on one occasion with the most dilute samples. The results indicate that Phase III mushroom substrate is vulnerable to infection by T. aggressivum when the fully colonised substrate is broken up and mixed during bulk handling operations, identifying a previously unidentified risk for Phase III substrate producers. 相似文献
349.
Stanislav Vacek Michal Hejcman Věra Semelová Jiří Remeš Vilém Podrázský 《European Journal of Forest Research》2009,128(4):367-375
In 1998, a fertilizer experiment aiming to investigate the effects of slow-release N, P, K and Mg fertilizer (SILVAMIX Mg NPK®) on a 60-year-old spruce stand with symptoms of yellowing was established. In this paper, trees were selected to investigate the relation between annual diameter increment, yellowing, foliation, needle and soil chemical properties: ten from the fertilized treatment (F), ten green trees from the control (CG) and ten yellow trees from the control (CY). CG and CY trees were growing in close proximity at a distance of only several meters apart under the same soil conditions. In treatment F, increased annual diameter increment, improved foliation, needle Mg concentration, plant-available Mg and P concentrations in the soil and absence of yellow trees were recorded 7 years after a single application of the fertilizer. During the last 15 years, annual growth increment and foliation of CY trees have continuously decreased while relatively stable values were recorded for CG trees and increased for F trees. In 2006, CG and CY trees differed significantly in Mg concentration in needles, foliation, yellowing and annual diameter increment. Although differences in soil chemical properties between CG and CY treatments were not significant, lower concentrations of plant-available Mg2+ and higher concentrations of H+ and Al3+ were found in soils under CY trees. There was a negative correlation between soil concentration of Mg and yellowing, but this correlation was relatively weak, indicating that there is no simple relation between soil and needle concentrations of Mg. In the investigated locality, the “new type” of yellow tree decline has been a long-term gradual process. 相似文献
350.
Makoschey B Franken P Mars JM Dubois E Schroeder C Thiry J Alvarez M Rypuła K Cavirani S Arnaiz I Houtain JY Bartak P Brownlie J Wolf G Meyer G Klees W Beer M Moennig V Thiry E 《Berliner und Münchener tier?rztliche Wochenschrift》2010,123(11-12):519-21, 516-8
Control of IBR and BVD should be possible in Europe. Effective vaccines and reliable tools for monitoring are available. Systematic approach and strict implementation of control measures are essential. Voluntary or mandatory programs are ongoing on regional or national level in a lot of countries. Successful programs put pressure on surrounding regions/countries to initiate control program as well. 相似文献