Die Eigenschaften der Bodenkörner und die Plastizität der Böden

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Influence of soil on the efficacy of entomopathogenic nematodes in reducing Diabrotica virgifera virgifera in maize

The use of entomopathogenic nematodes is one potential non-chemical approach to control the larvae of the invasive western corn rootworm (Diabrotica virgifera virgifera LeConte, Coleoptera: Chrysomelidae) in Europe. This study investigated the efficacy of Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), Heterorhabditis megidis Poinar, Jackson and Klein (Rh., Heterorhabditidae) and Steinernema feltiae Filipjev (Rh., Steinernematidae) in reducing D. v. virgifera as a function of soil characteristics. A field experiment was repeated four times in southern Hungary using artificially infested maize plants potted into three different soils. Sleeve gauze cages were used to assess the number of emerging adult D. v. virgifera from the treatments and untreated controls. Results indicate that nematodes have the potential to reduce D. v. virgifera larvae in most soils; however, their efficacy can be higher in maize fields with heavy clay or silty clay soils than in sandy soils, which is in contrast to the common assumption that nematodes perform better in sandy soils than in heavy soils

Classification and Definition of Social Anthropology A Comparative Study from a Hermeneutical Point of View

The purpose of this thesis is to study the relationship between the definition and bibliographical classification of a certain academic subject; social anthropology. The theoretical framework consists of views held in Information Science regarding the definition and classification of subjects. The methodological onset is based on hermeneutical concepts that allow an extended analysis of abstract structures of thought. This analysis comprises of two parts; a descriptive analysis and a comparative analysis. The result of the descriptive analysis, whose aim is to describe the academic subject social anthropology, shows that this is not easy to define, instead it is nowadays almost the same as cultural anthropology. The comparative analysis results partly in a definition of the academic subject social anthropology, partly it shows that there are pronounced differences in how the SAB and the Dewey bibliographical schemes classify social anthropology. My interpretation is that the social anthropological research more or less vanishes in the classification. In the SAB social anthropology has no division of its own, in the Dewey it has its own division but it is not clearly defined. Therefore it can seem like that the SAB is better adjusted to the research of today than the Dewey is. My theoretical framework provides me with valuable viewpoints, because they make me aware of the difficulties with subject definition. The methods recommended show me that there is a conflict between a changing academic discipline and the representation of it. I also found out that there are risks of using predetermined terms and divisions during indexing, they might restrict the subject contents. My final conclusion is that further studies about how documents dealing with cultural- and social anthropology are indexed, might explain more about the relationship between the bibliographic schemes and the research in these areas.Uppsatsnivå: