249 research outputs found
Use of Fungi for Pest Control in Sustainable Agriculture
The registration procedures for microbial pesticides have been based by and large on those developed for registration of chemical pesticides. However, fungi as living organisms differ in many aspects from inert substances. These differences are pointed out and discussed in the light of practical experiences. A pragmatic registration procedure is proposed taking into account the use of a fungus based product in relation to its natural distribution and behaviour. On the one hand, the use of a fungus naturally occurring on the target host does not need a sophisticated registration procedure. On the other hand, however, a genetically altered fungus applied against a non natural host in a non natural habitat needs very careful examination
Entomopathogenic fungi – a fascinating field of research
Mehr als 800 Arten von Pilzen sind als Pathogene von Insekten und anderen Arthropoden beschrieben (Tab. 1). Ohne Zweifel stellen diese Arten erst einen Bruchteil der tatsächlich existierenden Arten dar. Das zunehmende Interesse an diesen Pilzen und die um genetische Methoden erweiterten Identifikationsmöglichkeiten lassen ein rasches Ansteigen der Artenzahlen erwarten. Im Gegensatz zu den meisten anderen insektenpathogenen Organismen infizieren sie ihre Wirte durch die Kutikula. Sie sind weltweit verbreitet und spielen eine wichtige Rolle als natürliche Regulierungsfaktoren.More than 800 species of fungi are described as pathogens of insects and other arthropods. Many of them play a significant role in the natural regulation of insect and mite populations. The best known representatives belong to the anamorphic fungi (Deuteromycota), to the Clavicipetales (Ascomycetes) and to the Entomophthorales (Zygomycota). Some of the anamorphic fungi are used as biocontrol agents but also as indicators to assess soil and farm management. Most entomopathogenic fungi are specialised and have a narrow host range. The highest degree of specialisation exists with the Entomophthorales which are not only closely adapted to their hosts but able to alter their behaviour in order to maximise their own reproductive potential
White grub control with fungi
Engerlinge, die Larven der Scarabaeidae (Coleoptera), gehören weltweit zu den wichtigsten Bodenschädlingen und ihre Bedeutung scheint zuzunehmen. Wirksame, aber umweltschädigende und gesundheitsgefährdende Insektizide wurden verboten. In gewissen Regionen oder für bestimmte Indikationen waren nie welche bewilligt und im biologischen Anbau standen keine Bekämpfungsmittel zur Verfügung. Aus diesen Gründen wurde die Entwicklung von Mykoinsektiziden gegen Ende des letzten Jahrhunderts forciert. Heute stehen in der Schweiz zwei Produkte zur Verfügung: Ein Produkt basierend auf Beauveria brongniartii (Sacc.) Petch (Ascomycetes, Clavicipitaceae) zur Bekämpfung der Maikäfer (Melolontha melolontha L.)-Engerlinge und ein anderes basierend auf Metarhizium ansiopliae (Metschn.) Sorokin (Ascomycetes, Nectriaceae) zur Bekämpfung der Engerlinge des Juni- und des Gartenlaubkäfers [Amphimallon solostiale L., A. majale (Razoum.), Phyllopertha horticola L.]. Ersteres ist seit seiner Markteinführung 1991 zum Mittel der Wahl geworden, rund 2500 ha wurden bis heute damit behandelt (Keller, 2000a, 2004). Die Erfahrungen zeigen, dass besonderes Augenmerk auf die Qualität des Produktes und die Applikation sowie auf den Applikationszeitpunkt gelegt werden muss. Mit genetischen Markern stehen wirksame Hilfsmittel zum Studium der Ausbreitung, der Persistenz und der Nebenwirkungen zur Verfügung (Enkerli et al. 2001). Bei der Anwendung von M. anisopliae bestehen noch wenige Praxiserfahrungen. Das Produkt wurde bisher vorwiegend auf Golfplätzen eingesetzt. Über Langzeitwirkungen, die im Falle der Blastosporenanwendung von B. brongniartii gut dokumentiert sind (Keller, 2004), liegen erst wenige Daten vor. In den letzten Jahren wurden vermehrt Engerlingsschäden beobachtet, die durch zwei oder mehr Arten von Engerlingen verursacht werden. Wenn Maikäfer-Engerlinge beteiligt sind, stellt sich das Problem, dass zwei Pilzarten zur Bekämpfung eingesetzt werden müssen. Zur Zeit laufen Untersuchungen in solchen Schadgebieten, die Aufschluss geben werden über die wirksamste Art der Behandlung und über mögliche Interaktionen zwischen den Pilzen. In diesem Beitrag werden die neuesten Untersuchungsergebnisse vorgestellt.In Switzerland four species of white grubs (larvae of Coleoptera, Scarabaeidae) cause damages. The most important one is Melolontha melolontha L., a pest mainly of grassland in alpine regions. The other species, Amphimallon solstitiale L., A. majale (Razoum.) and Phyllopertha horticola L. cause damages mainly in lawn and turf. All these species have entomopathogenic fungi as naturally occurring enemies. Beauveria brongniartii (Sacc.) Petch (Ascomycetes, Clavicipitaceae) is registered to control M. melolontha, and Metharhizium anisopliae (Metschn.) Sorokin (Ascomycetes, Nectriaceae) is currently used to control Amphimallon spp. and P. horticola. Several field trials are ongoing to study long-term effects of the treatments and possibilities to improve the effectiveness. Both fungi showed good potential to control their hosts within a season when applied in spring. In the following generation they were still effective and were present in the untreated plots, thus showing their ability to be disseminated probably by soil water and small soil invertebrates. A crucial point is the correct application of the product which must be placed at the soil depth where the grubs are active. Studies to control white grub species associations with simultaneous application of both fungi show possible interactions between the two fungi but need further investigations
Susceptibility of different life stages of Rhagoletis cerasi to entomopathogenic fungi
Die Kirschfruchtfliege Rhagoletis cerasi Loew (Diptera: Tephritidae) ist der wichtigste Schädling im Süßkirschenanbau in Europa. Bei unbehandelten Bäumen können bis zu 100% der Kirschen Madenbefall aufweisen. Da Handel und Verbraucher nur einen Befall von maximal 2% tolerieren, sind effiziente Bekämpfungsmaßnahmen gefragt. Der bisher verwendete Wirkstoff Dimethoate könnte im Zuge der Re-Evaluation von Pflanzenschutzmitteln in der EU seine Zulassung verlieren. Danach stünde die gesamte Kirschenproduktion in Europa vor der gleichen Situation wie derzeit der biologische Landbau: eine Regulierung der Kirschfruchtfliege wäre nur noch über Leimfallen oder durch den Einsatz von Netzen möglich. Beide Methoden sind sehr arbeitsintensiv und oft nicht ausreichend wirksam. Der Einsatz von Mikroorganismen als Biocontrol-Maßnahme könnte eine Alternative darstellen. Die Verwendung von entomopathogenen Pilzen zur Bekämpfung von Tephritiden wurde in den letzten Jahren von mehreren Autoren beschrieben (Anagnou-Veroniki et al., 2005; Ekesi et al., 2005; Konstantopoulou & Mazomenos, 2005; Yee & Lacey, 2005), wobei bisher noch keine Erfahrungen zu R. cerasi vorliegen. Ziel dieser Untersuchung war die Beurteilung verschiedener Pilzstämme (Deuteromycotina: Hyphomycetes) hinsichtlich ihrer Pathogenität und Virulenz gegen die Kirschfruchtfliege.The effects of six fungus strains (Deuteromycotina: Hyphomycetes) on the mortality of different life stages of the European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae), were assessed in a series of laboratory experiments. All fungus strains caused mycoses in larvae and adults of R. cerasi. Virulence however varied considerably between the strains. Effects on L3-larvae were negligible; none of the fungus strains caused mortalities of more than 25% of larvae. Adults by contrast were highly susceptible to fungal infection. Beauveria bassiana and Paecilomyces fumosoroseus caused 90 to 100% mortality and had a strong influence on fecundity. Metarhizium anisopliae also showed reliable effects. The pathogenicity of Paecilomyces farinosus was low. Higher conidia concentrations lead to higher mortality, whereas B. bassiana was most efficient at low concentrations. Young flies showed lower mortality rates than older flies but, sub-lethal effects on eclosion rate of eggs were greater in young than in older flies
Field efficacy of entomopathogenic fungi to control Rhagoletis cerasi
Die Kirschfruchtfliege Rhagoletis cerasi Loew (Diptera: Tephritidae) ist der wichtigste Schädling im Süßkirschenanbau in Europa. Bei unbehandelten Bäumen können bis zu 100% der Kirschen Madenbefall aufweisen. Da Handel und Verbraucher nur einen Befall von maximal 2% tolerieren, sind effiziente Bekämpfungsmaßnahmen gefragt. Der bisher verwendete Wirkstoff Dimethoate könnte im Zuge der Re-Evaluation von Pflanzenschutzmitteln in der EU seine Zulassung verlieren. Danach stünde die gesamte Kirschenproduktion in Europa vor der gleichen Situation wie derzeit der ökologische Landbau: eine Regulierung der Kirschfruchtfliege wäre nur noch über Leimfallen oder durch den Einsatz von Netzen möglich. Beide Methoden sind sehr arbeitsintensiv und oft nicht ausreichend wirksam. Im Labor wurden mehrere Pilzstämme gegen verschiedene Entwicklungsstadien der Kirschfruchtfliege geprüft, mit dem Ergebnis, dass nur adulte Fliegen befallen werden. Dabei zeigten die Pilze Beauveria bassiana und Paecilomyces fumosoroseus die beste Wirkung. Diese beiden Pilze, die bereits in kommerziellen Produkten formuliert sind, wurden 2006 in zwei Feldversuchen gegen adulte Kirschfruchtfliegen appliziert.Two myco-insecticides, Naturalis-L (Beauveria bassiana) and PreFeRal®WG (Paecilomyces fumosoroseus), were applied against adult R. cerasi Loew (Diptera: Tephritidae) in two orchards in north-western Switzerland in summer 2006. Both products were able to cause mycosis on adult flies under field conditions. However, only Naturalis-L significantly reduced the number of damaged fruits (efficacy: 69-74%), whereas damaged fruits were not significantly reduced with PreFeRal (efficacy: 27%). For B. bassiana living fungal propagules were still detectable seven days after application while the fungal propagules of P. fumosoroseus remained only three days. A control of R. cerasi with myco-insecticides seems possible under field conditions; however, the application regime still has to be improved
Professionalisation and governance in Swiss sports clubs – Establishing a club office
Introduction
Sports clubs in Switzerland face increasing expectations and challenges from internal and external stakeholders. Therefore, more and more sports clubs professionalise their structures and processes, e.g., by establishing a club office with (part-time) employees. Since there is little knowledge in the sports management literature about the causes, forms and consequences of establishing a club office, this study answers the following research questions based on the multi-level framework from Nagel et al. (2015): Why and how do Swiss sports clubs establish a club office? What are the consequences of establishing a club office?
Methods
We selected five Swiss sports clubs in the context of a multiple case study design (Yin, 2014). Case selection aimed to include sports clubs of varying sizes, sports and professionalisation types. Data were collected through document analysis, expert interviews with decision-makers and focus groups with club members. Data were analysed using causation coding (Miles et al., 2014).
Results
Findings show different causes for establishing a club office. The main reason was to relieve volunteer board members. The various causes imply different roles and responsibilities of the established club office. While in some sports clubs, the club office is primarily responsible for administrative tasks, in others, it is also responsible for sponsorship. This circumstance explains why some sports clubs did not have to increase their membership fees to finance the club office because they could increase their sponsorship revenue. Although the club office staff is paid in all sports clubs, the volume of work varies. However, the paid staff often works more than agreed (“volunteer professionals”). Regarding the consequences, all sports clubs that established a club office are satisfied with their decision. Positive consequences are that a “place to go” was created for internal and external stakeholders, and many club processes are more efficient now. However, establishing a club office with (part-time) employees raises the question of strategic and operational responsibilities and decision-making power.
Discussion/Conclusion
The findings offer several implications for sports clubs that want to establish a club office. At the same time, the study provides further research perspectives. First, it might be insightful to analyse if there are any relevant differences in whether a sports club transforms its secretariat into a club office or establishes a club office for the first time. Second, there are further changes regarding the organisational structures and processes that are worth looking at when analysing the establishment of a club office, such as creating an executive/management board or employing a (paid) CEO. To conclude, it might be interesting to analyse sports clubs that have established a club office but shut it down after a while.
References
Miles, M. B., Hubermann, A. M., & Saldaña, J. (2014). Qualitative Data Analysis. A Methods Sourcebook (3rd ed.). SAGE.
Nagel, S., Schlesinger, T., Bayle, E., & Giauque, D. (2015). Professionalisation of sport federations–A multi-level framework for analysing forms, causes and consequences. European Sport Management Quarterly, 15(4), 407–433. https://doi.org/10.1080/16184742.2015.1062990
Yin, R. K. (2014). Case Study Research: Design and Methods (5th ed.). SAGE
Temperature dependent resistivity under pressure and magnetoresistance data of the organic superconductor (BEDO-TTF)2ReO4(H2O)
The temperature dependence of the resistivity under pressure (up to 6 kbar) of the organic metal (BEDO-TTF)2ReO4(H20) is reported. An increase of the resistivity below 35 K, which is observed at ambient pressure, is already suppressed at 1 kbar. In addition at this pressure the superconducting transition sharpens and the onset temperature of 2.3 K is nearly the same as at ambient pressure. Magnetoresistance data, observed at 1.3 K and 6.7 Tesla show a strong angle dependence. In addition at 1.3 K first SdH -oscillations in the magnetoresistance are found already at such low fields as 5 Tesla
Bulk superconductivity at ambient pressure in polycrystalline pressed samples of organic metals
Bulk superconductivity in polycrystalline pressed samples of αt-(BEDT-TTF)2I3 and βp-(BEDT-TTF)2I3 is reported. This finding shows that organic superconductors can be used in principle for the preparation of electronic devices and superconducting cables
[DL-1,2-bis(2-hydroxyphenyl)ethylenediamine]dichloroplatinum(II), a new compound for the therapy of ovarian cancer
The synthesis of diastereoisomeric [1,2-bis(2-hydroxyphenyl)ethylenediamine]dichloroplatinum(II) complexes, DL-3-PtCl2 and meso-3-PtCl2, and their evaluation on the hormone-independent, human MDA-MB231 breast cancer cell line, on the cisplatin-sensitive and -resistant L1210 leukemia cell line, on the cisplatin-resistant human NIH:OVCAR 3 ovarian cancer cell line, on the P-388 leukemia of the mouse and on the cisplatin-sensitive and -resistant Ehrlich ascites tumor of the mouse are described. On all tumor models DL-3-PtCl2 produces a marked inhibitory effect. The diastereoisomer meso-3-PtCl2 is less active and more toxic. It is striking that DL-3-PtCl2 leads to a pronounced inhibition of all cisplatin-resistant tumors. At non-toxic concentrations DL-3-PtCl2 produces cytocidal effects on the NIH:OV-CAR 3 cell line. Therefore DL-3-PtCl2 is of interest for further evaluation for the therapy of ovarian cancer
Organic metals from chiral BEDT-TTF donors
We have shown that is is possible to obtain organic metals from chiral molecules. The X-ray results prove an oxidation number of + 1.5 for the radical cations in at least two cases. To our best knowledge. these are: the first examples of BEDT-TTF-related radical cation salts with this oxidation number. As expected, we obtained statistically disordered crystals, containing the two different enantiomers in a "racemic" mixture. The broad smeared-out phase transitions are probably due to this disorder, or may be caused by the three-dimensional interactions which have been observed, so far, only once in a BEDT-TTF radical salt. We will crystallize the metallic compounds using "optically pure" isomers, in the hope to be able to isolate chiral metals
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