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The European (Melolontha melolontha L.) and Forest (M. hippocastani F.) cockchafer are widespread pests throughout Central Europe. Both species exhibit a 3-5-year life cycle and occur in temporally shifted populations, which have been monitored and documented for more than 100 years. Visual identification of adults and larvae belonging to these morphologically similar species requires expertise and, particularly in the case of larvae, is challenging and equivocal. The goal of the study was the development of an efficient and fast molecular genetic tool for the identification and discrimination of M. melolontha and M. hippocastani. We established a collection of both species from Switzerland, Austria and Northern Italy in 2016, 2017 and 2018. An approximately 1550 bp long fragment of the cytochrome c oxidase subunit 1 (CO1) mitochondrial gene was amplified and sequenced in 13 M. melolontha and 13 M. hippocastani beetles. Alignment of the new sequences with reference sequences (NCBI GenBank and BOLDSYSTEMS databases) and subsequent phylogenetic analysis revealed consistent clustering of the two species. After the identification of M. melolontha and M. hippocastani species-specific single nucleotide polymorphisms (SNPs) in the CO1 alignment, we developed an effective SNP tool based on the ABI PRISM (R) SNaPshot (TM) Multiplex Kit for the rapid and accurate species discrimination of adults and larvae., Bulletin of Entomological Research, 111 (5), ISSN:0007-4853, ISSN:1475-2670

The European (Melolontha melolontha L.) and Forest (M. hippocastani F.) cockchafer are widespread pests throughout Central Europe. Both species exhibit a 3-5-year life cycle and occur in temporally shifted populations, which have been monitored and documented for more than 100 years. Visual identification of adults and larvae belonging to these morphologically similar species requires expertise and, particularly in the case of larvae, is challenging and equivocal. The goal of the study was the development of an efficient and fast molecular genetic tool for the identification and discrimination of M. melolontha and M. hippocastani. We established a collection of both species from Switzerland, Austria and Northern Italy in 2016, 2017 and 2018. An approximately 1550 bp long fragment of the cytochrome c oxidase subunit 1 (CO1) mitochondrial gene was amplified and sequenced in 13 M. melolontha and 13 M. hippocastani beetles. Alignment of the new sequences with reference sequences (NCBI GenBank and BOLDSYSTEMS databases) and subsequent phylogenetic analysis revealed consistent clustering of the two species. After the identification of M. melolontha and M. hippocastani species-specific single nucleotide polymorphisms (SNPs) in the CO1 alignment, we developed an effective SNP tool based on the ABI PRISM® SNaPshot™ Multiplex Kit for the rapid and accurate species discrimination of adults and larvae.

Innovative biological pest control of the western corn rootworm (WCR) Diabrotica virgifera virgifera and wireworms Agriotes spp. in maize and potato cultivation in Europe is driven by (1) the economic damages caused and (2) the restrictions on chemical pesticides. We analyze the efficacy of biological control agents for WCR and wireworms based on European field trails. A partial equilibrium displacement model is used to estimate the changes in producer and consumer surplus for France, Italy, Spain, Germany, Austria and Romania given different adoption ceiling and adoption speed. Furthermore, the benefit of a potential reduction in pesticide use due to biological control application is evaluated. The results suggest a total annual welfare gain of ca. €190 million from biocontrol of WCR in maize production for the countries under consideration at an adoption ceiling and adoption speed of 30% and 2.41, respectively. In potato production, an annual welfare gain of over €2 million may be recorded in ecological and/or organic cultivation. Overall, the biological control methods provide an economical alternative in maize and can contribute to increase the competitiveness of European Union (EU) agriculture, while they look promising for certified organic potato production at the current level of control efficiency.

The western corn rootworm, Diabrotica virgifera virgifera LeConte, is one of the most deleterious pests of corn worldwide. Severe root injury interferes with the roots` ability to absorb water and nutrients and results in plant lodging and yield losses. After the pupation in the soil, the emerged adults primarily feed on leaves, corn silk, pollen, and kernels on exposed ear tips of corn. An absolute sampling method for adult western corn rootworm was developed exploiting the strong positive phototropic and negative geotactic behaviour of this coleopteran species. The novel developed pyramidal designed emergence trap is characterized by numerous features which facilitate the estimation of western corn rootworm populations in the field: The trap is highly efficient, simple and economical to construct, portable, easy and quick to install, durable and thus nearly maintenance-free. The installation of the trap relies on cutting corn plants at a height of 20 cm. Both the efficacy of recapturing of ten...

Entomopathogenic fungi are used for biological control of insect pests. Metarhizium brunneum Petch (Hypocreales) has potential to control Diabrotica virgifera virgifera LeConte (Chrysomelidae), which is a major pest of maize in North America and has recently invaded Europe. The inundative application of an entomopathogenic fungal strain in biological control results in high densities of fungal propagules in the soil which can potentially affect soil microbial communities and their multiple functions in soil. The objective of the present study was to assess potential effects of M. brunneum on soil fungal and prokaryotic communities in a pot experiment over a time course of 4 months using high-throughput sequencing (HTS) of ribosomal markers. The application of M. brunneum formulated as fungus colonised barley kernels (FCBK) led to a significant increase of the applied strain in soil, as assessed by cultivation-dependent (plating on selective medium followed by genotyping of Metarhizium isolates) and cultivation-independent (HTS of ribosomal markers) approaches. Data revealed that soil fungal and prokaryotic community structures did not change after the application of M. brunneum. Temporal changes of the fungal and prokaryotic communities were observed and the prokaryotic communities showed minor changes to barley kernels (BK), the matrix of the formulation. Results of this study are in accordance with other investigations lacking any evidence for adverse effects on microbial communities caused by applied entomopathogenic fungi., Biocontrol Science and Technology, 29 (6)

The entomopathogenic fungus Metarhizium brunneum is widely applied as a biological pest control agent. Consequently, its use has to be accompanied by a risk management approach, which includes the need to monitor the fate of its bioactive metabolites in the environment, for example, in treated crops. A fast and selective UHPLC-QTOF-MS method was developed to monitor the presence of secreted destruxins in two model food plants for the application of this fungal biocontrol agent, namely, strawberry and maize. The liquid chromatography-mass spectrometric assay for destruxin trace analysis is combined with a novel QuEChERS-based extraction protocol. The whole assay was optimized for the application in these crops, and it allows quantitative analysis of the major M. brunneum metabolites destruxin A, 1, destruxin B, 2, and destruxin E, 3, down to the parts per billion range. In strawberry, limits of quantitation (LOQs) were found to be

Melocont® Pilzgerste, a commercial product based on the entomopathogenic fungus Beauveria brongniartii (Sacc.) Petch (Ascomycota: Hypocreales) strain BIPESCO 2, was applied at different rates and time points over a period of 24 years in East-, North- and South Tyrol (Austria and Italy) to control the European cockchafer (Melolontha melolontha L. and M. hippocastani F.). Beauveria spp. density was assessed and Beauveria spp. isolates were characterized at species and genotype level using Bloc intergenic region sequence and simple sequence repeat marker analyses. BIPESCO 2 was detected at 41 % of the treated sites, predominantly at sites where the fungus was applied at least once during the four years prior to sampling. At one site BIPESCO 2 was detected 15 years after the last treatment. Results showed that applications should be repeated to achieve good persistence of the biological control agent, and it indicated that despite intensive applications diverse populations of B. brongniartii or Beauveria spp. consortia can coexist in these habitats.

It was a great honor for me to emotionally and scientifically celebrate with many others the 70th birthday of my friend and colleague Nico Stehr.

A fast and selective ultrahigh-performance liquid chromatography diode array detector (UHPLC-DAD) method combined with an off-line solid phase extraction (SPE) protocol was established to monitor destruxins (dtxs), a secondary metabolite class of highly bioactive cyclic depsipeptides. Sample purification via SPE was tailored to remove both more polar and apolar matrix constituents by applying analyte class-selective washing and elution conditions. To separate and detect destruxin congeners an UHPLC-DAD system hyphenated to a quadrupole-time-of-flight (Q-TOF) hybrid mass spectrometer was utilized. Analyses were performed on a sub-2-μm-particle-size RP-18 column with an acidified (0.02% acetic acid) 12 min water/acetonitrile solvent gradient. In the dtx congener elution zone 22 chromatographic peaks were separated. Four of these were identified by comparison with reference materials as dtx A, dtx B, dtx E, and dtx E-diol; 16 were tentatively assigned as known or novel dtx congeners by the analysis of high resolution UHPLC-DAD-QTOF-MS/MS data recorded in the positive electrospray ionization (ESI) mode. The applicability of the UHPLC-DAD assay to investigate biological materials in a qualitative and quantitative manner was proven by the application of the platform to monitor the dtx production profile of three Metarhizium brunneum strain fungal culture broths.

The entomopathogenic fungi Metarhizium brunneum, Beauveria bassiana, and B. brongniartii are widely applied as biological pest control agent in OECD countries. Consequently, their use has to be flanked by a risk management approach, which includes the need to monitor the fate of their relevant toxic metabolites. There are still data gaps claimed by regulatory authorities pending on their identification and quantification of relevant toxins or secondary metabolites. In this chapter, analytical methods are presented allowing the qualitative and quantitative analysis of the relevant toxic B. brongniartii metabolite oosporein and the three M. brunneum relevant destruxin (dtx) derivatives dtx A, dtx B, and dtx E.

Amending plant growing media with biocontrol agents is becoming an increasingly popular strategy for protecting plants against insect pests and diseases. Although this practice offers potential for pest and disease control, very little is known about the influence of introduced microbes on the indigenous microbial communities and vice versa. This study examines fungal and bacterial community structures of diverse horticultural growing media and evaluates their interactions with a plant Euonymus fortunei and/or the insect pathogenic fungus Metarhizium anisopliae. Complementary physiological (Biolog™) and molecular (automated ribosomal intergenic space analysis – ARISA) techniques were applied to analyse community structure and diversity over 1 yr. These studies clearly showed distinct microbial communities in different plant growing media. Irrespective of media or any treatment, initial microbial diversity was very low but increased significantly over 1 yr. A succession of new fungal and bacterial species was observed, with species originally present being displaced. This succession led to the establishment of distinct microbial community structures for each medium over 6–12 months. ARISA studies showed that bacterial and fungal community profiles were influenced by the presence of plant and M. anisopliae, but in complex ways depending on the medium. Certain microbes were specifically associated or inhibited by the presence of M. anisopliae and/or E. fortunei. Physiological studies, however, showed that neither M. anisopliae nor plant had any significant effect on the communities' ability to decomposition a batch of carbon sources. Although diverse microbial communities were observed in different media, none of these communities influenced the efficacy of M. anisopliae.

Nutritional conditions causing droplet exudation by Metarhizium anisopliae var. anisopliae were studied. Exudation in droplets occurred only on media with more than one carbon source and was highly dependent on the ratio of a well metabolized sugar such as trehalose and a nonpreferred sugar, in particular arabinose. Exuded droplets contained destruxin A, B and E in concentrations similar to those on submerged culture on Czapek Dox medium with equivalent C : N ratios but was clearly less than previously reported on standard Czapek Dox or Sabouraud dextrose broth. Destruxins also were found in agar samples from directly below mycelium and from up to 2 cm from the colony edge. Exudates retrieved from different media were proven to have Pr1 protease-related enzyme activity. Additional HPLC analysis indicated that droplets from diverse media did not differ in their sugar and acid content. A hypothesis is presented regarding the trigger for guttation in Metarhizium during growth under these conditions.

Selected biological control agents and conventional pesticides were used to critically review the applicability of a newly developed Risk Indicator (RI) system. Five basic components are proposed for the calculation of the overall environmental risk score: persistence of the active ingredient, dispersal potential, range of non-target organisms that are affected, and direct and indirect effects on the ecosystem. Several risk measurement systems were reviewed; risk categories in the proposed system were modified from a model developed for classical biocontrol agents. Additionally, one new category was included, to assess the risks to vertebrate non-target species. Besides a detailed discussion of the new RI model, the suitability of the model was demonstrated by calculating the risk scores for 17 selected products. It became obvious that the environmental risk score varied greatly within the assessed chemical products, and also within the group of biological products. The use pattern greatly influe...

Destruxins (dtx) A, B, and E, showing a variety of biological activities, are the main toxic secondary metabolites of the entomopathogenous ascomycete Metarhizium anisopliae Bipesco 5, a widely used biocontrol production strain. Dynamics of dtx biosynthesis were monitored during liquid fermentation in a chemically defined medium. During shake flask cultivation with excess carbon, nitrogen and phosphate, approximately 50, 20, and 100 mg l–1 dtx A, B, and E were produced after 12 d. Destruxins were produced during exponential growth phase and in the stationary phase. Carbon exhaustion in the culture broth was demonstrated to affect destruxin production to a minor degree: Absolute dtx amounts in the liquid increased also after glucose exhaustion; dtx amounts referred to biomass increased further evidently in shake flasks or slightly in bioreactor experiments after carbon limitation occurred. Contrarily, nitrogen exhaustion resulted in an evident decline in dtx amounts referred to biomass. Absolute amounts in the culture broth, however, still increased slightly the following four days in bioreactor experiments. From this we conclude that dtx production is highly influenced by nitrogen availability. Generally, dtx production in bioreactors with controlled aeration (1 vvm) was significantly lower than in shake flasks. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Diabroticina is a speciose subtribe of New World Chrysomelidae (Subfamily Galerucinae: Tribe Luperini) that includes pests such as corn rootworms, cucumber beetles and bean leaf beetles (e.g. Diabrotica, Acalymma, Cerotoma species). The evolution and spread of pesticide resistance, the European invasion of Diabrotica v. virgifera LeConte, and possible development of resistance due to the large-scale deployment of Diabrotica-active Bt maize in North America have generated a sense of urgency in developing biological control options against Diabroticina pests. In the present study, we review available knowledge on biological control options, including 290 publications on natural enemy–Diabroticina associations in the New World. Several natural enemy species or groups appear to be promising candidates for control strategies with different ecological rationales. We propose that future research should pursue: (1) development of inundative biological control products, particularly mass-produced entomopa...

Zusammenfassung Seit Anfang der 90er Jahre ist die Globalisierung in aller Munde. Der Beitrag beleuchtet den kulturellen Wandel, der sich im Globalisierungsdiskurs sozialer Beziehungen in Unternehmen und Offentlichkeiten vollzieht. Globalisierung dient als externe Zurechnungsinstanz von Sachzwangpolitik. Wahrend der zunehmende globale Austausch von Gutern und Dienstleistungen den Burger in neuartige ungleiche Beziehungen fuhrt, bleiben seine institutionellen Wege, um Unzufriedenheit zum Ausdruck zu bringen, auf zunehmend unangemessene, nationale Kanale angewiesen. Abstract Since the 1990’s globalization is on everybody’s mind and discussed in all media. This article throws light on the cultural change taking place in these discussions as far as social relationships in corporations and the public sphere are concerned. Globalization serves as a policy of external attribution of inherent necessity. While the citizen is led into new unequal relations by the increasing global exchange of goods and services, hi...

Aims: Synthetic media should be designed for the production of Metarhizium anisopliae conidia with improved virulence properties. Methods and Results: A genetic algorithm (GA), demonstrated to be suitable for the design of media for spore mass production (Hutwimmer et al. 2008), was utilized for a multi-objective medium design to improve conidia yield and three proposed virulence properties of conidia: C : N ratio, germination speed and amount of spore-bound Pr1 protease. After five iterative optimizations, 52 media were improved over Sabouraud dextrose agar (SDA). Four media exhibited medium performances (a factor derived from the four single optimization variables) of around 0·7; cf. SDA = 0·532; media with enhanced properties were reached for each single optimization variable; Bioassays against Tenebrio larvae indicated also a slight improvement in virulence of conidia from designed media. A degenerated phenotype of the same strain did not exhibit differences in colony appearance, spore characteristics and virulence if grown on designed media. Conclusions: The application of a problem-oriented GA is a practical and rapid method to design media for multi-objective purposes. Significance and Impact of the Study: The applicability of a GA for multi-objective medium design was demonstrated for the cultivation of anamorphic fungi on solid media.

Seit Ende der 1990er Jahre verzeichnet Deutschland einen Anstieg der Armutsrisikoquote. Bezogen auf alle Einwohner der Bundesrepublik durfte sich diese deutlich von 10 auf 15–16 Prozent erhoht haben (vgl. Deckl 2013).

The entomopathogenic fungi Metarhizium brunneum, Beauveria bassiana, and B. brongniartii are widely applied as biological pest control agent in OECD countries. Consequently, their use has to be flanked by a risk management approach, which includes the need to monitor the fate of their relevant toxic metabolites. There are still data gaps claimed by regulatory authorities pending on their identification and quantification of relevant toxins or secondary metabolites. In this chapter, analytical methods are presented allowing the qualitative and quantitative analysis of the relevant toxic B. brongniartii metabolite oosporein and the three M. brunneum relevant destruxin (dtx) derivatives dtx A, dtx B, and dtx E.

A fast and selective ultrahigh-performance supercritical fluid chromatography photodiode array detector method was established for the qualitative and quantitative analysis of destruxins, cyclic hexadepsipeptides, from fungal culture broth samples. Prior to analysis, sample purification was carried out using an off-line solid-phase extraction protocol on a reversed-phase material in order to remove unwanted matrix constituents. For separation, detection, and identification, an ultrahigh-performance supercritical fluid chromatography photodiode array detector system hyphenated to a triple quadrupole mass spectrometer was utilized. Analyses were performed on an Acquity ethylene bridged hybrid 2-ethylpyridine sub 2 µm particle size column with CO2 and an acidified (0.02% trifluor acetic acid) modifier mixture of methanol/acetonitrile (8/2 v/v) serving as mobile phase. For the optimal separation of destruxins, the amount of the modifier was increased in a 10 min linear gradient from 2% to 20%, and the column outlet pressure and temperature was set at 140 bars and 60 °C, respectively. Seventeen analytes were separated within an elution window of 4 minutes. Five destruxin congeners (destruxin A, destruxin B, destruxin D, destruxin E, and destruxin E-diol) were identified using reference material. Additionally, eight analytes were tentatively assigned as known destruxins by the evaluation of mass spectrometry data performed as multiple reaction monitoring experiments in the positive electrospray ionization mode.

A novel high yield isolation procedure for lipophilic cyclic peptide derivatives is presented. Destruxin (dtx) A, B, D, E, and E-diol retrieval from Metarhizium anisopliae culture broth was achieved with a three-step purification protocol. After liquid-liquid extraction column chromatography over Sephadex LH-20 served as enrichment step. High-speed counter-current chromatography (HSCCC) was used for the final purification. Within the first chromatographic step dtx D and dtx E-diol were separated in purities exceeding 90%. The separation of dtx A, B, and E was achieved from an enriched Sephadex LH-20 fraction by a HSCCC protocol using light petroleum-ethyl acetate-methanol-water = 2:5:2:5 (v/v) as eluent system. These derivatives were obtained in purities above 98% and total yields exceeding 40%.

A high-performance liquid chromatography-diode array detection (HPLC-DAD) assay is described for the detection and quantification of the secreted Beauveria brongniartii metabolite oosporein from potato tubers. Analyte recovery was achieved with a Britton-Robinson buffer system at pH 5.5 diluted with methanol 3:7 (v/v) (BR5.5-MeOH). An internal standard protocol using 2-iodobenzoic acid was established to minimize analytical error. The resulting assay, using a binary solvent gradient with acidic modifiers and detecting the metabolite at 287 nm, showed a limit of detection (LOD) of 2.4 mg oosporein/kg potato tubers. The oosporein content of potato tuber samples obtained from a field trial using the biological pest control B. brongniartii formulation Melocont-Pilzgerste in up to five-fold higher doses (250 kg Melocont-Pilzgerste/ha) as recommended per year was found to be below the established LOD.

Non-target effects of the entomopathogenic fungus Beauveria brongniartii (Ascomycota: Clavicipitaceae) on Poecilus versicolor (Coleoptera: Carabidae), a potential antagonist of the European cockchafer Melolontha melolontha , were studied with three different B. brongniartii formulations, Melocont-Pilzgerste, Melocont-WP, and Melocont-WG. All formulations induced significantly enhanced mortality rates among third instar larvae of the target pest M. melolontha , but no negative effects on the non-target organism were observed. However, small but statistically significant differences were observed for P. versicolor when the fungus was applied: larval development time from first instar to adult stage was decreased by 6.8% (4 days) and the biomass of teneral beetles increased by 8.4% (3.7 mg) compared to that of the control groups. Additionally, third instar larvae of P. versicolor were exposed to B. brongniartii -infected M. melolontha cadavers to either consume material from the mycosed carcasses or come in contact with them while searching for food. Again, no significant negative effects on P. versicolor could be observed. The results suggest that under field conditions B. brongniartii would be a negligible risk for P. versicolor .

Zusammenfassung Für Durkheim ist Kriminalität eine ebenso normale wie notwendige gesellschaftliche Erscheinung. Kriminalität erfülle Funktionen, die für den Fortbestand und die Weiterentwicklung einer Gesellschaft wichtig seien. Durch Kriminalität würden die gesellschaftlichen Normen symbolisch verdeutlicht, solidarisierten sich die Gesellschaftsmitglieder und werde die zukünftige Moral antizipiert. Vor diesem Hintergrund scheint die Prävention von Kriminalität, wie sie zur Zeit in den Kommunen verstärkt betrieben wird, zum Scheitern verurteilt und kontraproduktiv für die gesellschaftliche Entwicklung zu sein. Dieser Beitrag untersucht, inwiefern auch Kriminalprävention gesellschaftliche Funktionen erfüllt, die jene der Kriminalität verstärken oder ergänzen. So dient Kriminalprävention vor allem zur Demonstration der Handlungs- und Steuerungsfähigkeit des Staates, zur symbolischen Normverdeutlichung; sie stiftet aber auch Identität und stärkt den Zusammenhalt der Bürger.

This investigation deals with the control effects of the insect pathogenic fungus Metarhizium anisopliae var. anisopliae on Daktulosphaira vitifoliae. In pot experiments, the soil surrounding phylloxera-infected grapes was inoculated with barley colonised with M. anisopliae. After thirty-two days, ineight of ten Metarhizium-applied pots nofresh phylloxera infections could be observed.In two of ten plants, a few fresh nodositiessingly occupied with phylloxera or phylloxeraeggs could be found. In all untreated plants,fresh nodosities with either single (two of sixplants) or multiple (four of six plants)occupation with phylloxera could be observed.M. anisopliae could be re-isolated in aconcentration of

A simple and accurate differential pulse polarographic method has been developed for the determination of oosporein in the culture broth of the fungus Beauveria brongniartii. This hydroxybenzoquinone derivative is the only major secondary metabolite secreted by this entomopathogenic fungus, which is used as biological pest control agent (BCA) against Melolontha melolontha larvae. It can be found in the host organism as well as in the formulated product. The polarographic behavior of oosporein was examined in various buffer systems over the pH range 3-10. In Britton-Robinson buffer/methanol solution (3:7 v/v, pH 5.5) the differential pulse polarograms exhibited reproducible peaks at E(p) = -0.18 V vs silver/silver chloride/potassium chloride (3 M). Under these conditions, a plot of peak height vs concentration of oosporein was found to be linear over the range 5.9 x 10(-)(7) to 2.5 x 10(-)(5) M (0.18-7.74 microg mL(-)(1); r = 0.9998). The detection limit was calculated to be 54 ng mL(-)(1). To evaluate the concentration of oosporein, the standard addition method was applied. The analysis of oosporein in the culture broth led to a mean value of 524.9 microg mL(-)(1) broth with a relative standard deviation (S(rel)) of +/-2.6%. The proposed polarographic method is accurate, not time-consuming, and it is of low cost because no separation steps are necessary.

This paper examines the life and career of the prominent sociologist Werner Stark (1909–1985), born and raised in Marienbad, Bohemia, and after 1918 in the multi-ethnic state of Czechoslovakia. As a prolific and wide-ranging scholar whose many works failed to find an enduring place in American sociology, Stark is a prime example of academic marginalisation. The authors analyse Stark’s major contributions from the standpoint of the sociology of knowledge. They argue that his ideas regarding human nature, the need for social discipline, and the desirability of community were rooted in a pervasive biographical marginality that found resolution in his conversion to Catholicism. In turn, these ideas reinforced the marginality from which they emerged. The reception of Stark’s work in the United States was governed by a perceived incompatibility of his outlook with the assumptions and goals of his American audience. In particular, Stark offered an explicitly value-directed sociology, one which asserted the importance of social order, individual discipline, and universal community, at a time (the 1960s and 1970s) when the field sought to maintain its credibility as an objective scientific discipline in the face of growing challenges from sociologists and non-sociologists alike. Stark’s American colleagues focused on aspects of his work that were incompatible with their own cultural and disciplinary orientations and this obscured the full range of his achievements, especially his analyses which anticipated contemporary sociological work.

In this provocative analysis of the central issues and developments in modern social theory, Dr Strasser contends that enquiry into the function, tasks and mission of sociology as a discipline can be understood only in relation to the subject's historical development. He believes that a discussion of the origin and intention of sociology, particularly in relation to the established social order, enables us to grasp fully the nature of sociological theory, both past and present. He maintains that a sociologist's own position in society, and consequently his views on its development and his way of expressing those views, will affect the theoretical position he takes up.

Entomopathogenic fungi are promising alternatives to chemical insecticides. However, a major hurdle concerning the registration of these fungi as plant protection agents is the possible toxicity of secreted metabolites, especially secondary metabolites. This review summarizes data on specific secondary metabolites (destruxins, efrapeptins, oosporein, beauvericin and beauveriolides) produced by the important genera Beauveria, Metarhizium and Tolypocladium . The quantities of secondary metabolites produced by these fungi in vivo are usually much less than those secreted in nutrient rich liquid media. Methods and strategies are suggested which could standardize the risk assessment of fungal biological control agents.

The phytotoxic potential of Beauveria brongniartii and its main secondary metabolite oosporein were evaluated against seed potatoes ( Solanum tuberosum ) both in vitro and in situ . In a tray test, potatoes were inoculated using conidiospores and grown either in garden soil or in B. brongniartii -enriched soil. The only significant effect of the treatment was the fact that the weight of the roots was different compared with the controls. The weight of haulm and tubers was unaffected by the treatment with B. brongniartii . No oosporein was detected in the potatoes, although the density of B. brongniartii in the soil was forty times higher than recommended for the usage of this biological control agent (BCA). This indicates that oosporein does not enter the food chain via potato tubers. The effect of BCA on seed potatoes was also tested in situ . No B. brongniartii was detected in the potato field before the application of BCA. Three months after application, an average of 3 &#50 10 4 colony forming units p...

Oosporein was the only major secondary metabolite produced by three commercial isolates of the entomopathogenic fungus Beauveria brongniartii in submerged cultures and on sterilised barley kernels. None of the other toxins (bassianin, beauvericin and tenellin) normally produced by Beauveria species were detected by sensitive HPLC and MS techniques. The maximum amount of oosporein produced in batch reactors was 270 mg l−1, after 4 days incubation, while that produced on sterilised barley kernels ranged between 2.0 and 3.2 mg kg−1, after 14 days incubation. The mean amount of oosporein detected in cockchafer larvae infected with B. brongniartii was 0.23 mg. Melocont®-Pilzgerste, a commercial product based on B. brongniartii, was not phytotoxic to Lepidium sativum and Phleum pratense nor were fungal metabolites detected in these indicator plants. No systemic effects of oosporein were observed in treated pasture turf maintained for several months in the greenhouse.

Heterotrophic microorganisms are able to solubilize metals via excreted metabolites-most often di- or tricarboxylic acids but also amino acids. With amino acids Cu, Zn, Au, Ni, U, Hg and Sb have been solubilized from metal oxides, metal sulfides or elementary metals. In this work it was investigated if excreted amino acids play a role in the leaching of zinc from a zinc oxide containing industrial filter dust. Two bacteria-Pseudomonas putida andCorynebacterium glutamicum-and a fungus-Penicillium simplicissimum were used.P. putida andP. Simplicissimum have already been used to solubilize zinc oxide, whereasC. glutamicum was used because of its known ability to excrete amino acids. Amino acids in culture fluids were analyzed via derivatization with phenyl isothiocyanate, separation on a RP-18 column and UV-detection. All three microorganisms solubilized zinc from the filter dust and excreted much more citric acid than amino acids. Thus citric acid rather than amino acids was regarded to be the leaching agent. Of the two bacteriaP. putida was more resistant towards the heavy metalcontaining filter dust.

Heavy metal-loaded sewage sludge was leached abiotically using FeCl2 and FeCl3 which are applied in waste water treatment plants to eliminate phosphate and for coagulation. Due to the hydrolyzing nature of ferric iron, ferric chloride (100 mmll L−1) was able to solubilize more than 90% of copper and zinc and more than 80% of cadmium, with an optimal pulp density of 3% (w/v), after 10 h of exposition at 25°C. Chromium, lead and nickel were solubilized to an extent of 40–70%. With the exception of copper (redoxolysis), all heavy metals monitored were leached following the principle of acidolysis. Chemical leaching with iron resulted in a secondary contamination of sewage sludge (96 g iron per kg dry weight). The insoluble iron compounds which were precipitated for adsorbed to sludge flocks could be resolubilized with oxalic acid (100 mM, pH