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The volatile organic compounds (VOCs) 1-octen-3-ol and 3-octanone produced by the entomopathogenic fungus Metarhizium brunneum are known to have pesticidal properties at high doses against a range of invertebrate pests. Very little is known about their behavior-modifying (semiochemical) properties. This study focused on investigating the behavioral responses of three subterranean crop pests, wireworm (Agriotes lineatus), western corn rootworm (Diabrotica virgifera virgifera), and garden chafer (Phyllopertha horticola), to relatively low doses of 1-octen-3-ol and 3-octanone. The behavior of wireworms and corn rootworms were slightly influenced by the VOCs, yet not significantly. Western corn rootworms appeared to be slightly attracted by 100 µl and 200 µl 1-octen-3-ol and 100 µl dose of 3-octanone, respectively but slightly repelled by the higher dose of 3-octanone. Wireworms appeared to be slightly repelled by 1-octen-3-ol and high dose 3-octanone, but slightly attracted by the 100 µl dose of 3-octanone. The VOCs had no significant impact on garden chafer. In silico studies showed that corn rootworm odorant binding proteins (OBPs) had a strong binding affinity of 1-octen-3-ol and high dose 3-octanone, indicating that these VOCs can be detected and recognized by corn rootworm. OBPs are well conserved between species; thus, wireworm and garden chafer OBPs should also be able to bind with the VOCs. Further trials will be done to confirm that VOCs could be used as semiochemicals. Appropriate formulation of the VOCs should increase their efficacy and prevent rapid dissipation of the VOCs. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

The individualization thesis has thoroughly challenged our picture of social inequality. The question whether social inequality today should be regarded as ‚structured‘ or rather ‚individualized‘ cannot be answered satisfactorily. Therefore, in our paper we present an alternative interpretation. Individualization constitutes an interpretative scheme (Deutungsmuster) of social inequality. Individualization does not stand for the end or ‚destructuration‘ of social inequality. Rather, it reminds us that research up until now has not adequately reconstructed what social inequality actually means. Especially class theorists have not taken Max Weber’s sociology aiming at the interpretive understanding of social action and thereby a causal explanation of its course and consequences seriously enough. Research in social inequality must reconstruct context specific motives of action and connect these interpretive data with quantitative distributions. In an asymmetric society (Coleman), it will focus on interpretative schemes of occupational classes, on the one hand, and interpretative schemes of informal groups, life styles and individual self-descriptions, on the other hand. So far, an elaborated concept of this kind is not available. The debate on individualization has at least shown that we need it. [ABSTRACT FROM AUTHOR]

In this paper it is shown that the recent debate over the explanatory power of traditional class theories has taken two routes. As such, It continues the fundamental debate between Marx and Weber. But on the one hand, we observe the neomarxist attempt to bridge the gap between an abstract class structure analysis on the level of the mode of production and a concrete class analysis on the level of collective actors. By introducing a marxist concept of the middle class, it is hoped to establish the class character of the "new" classes. On the other hand, following Weber's message of the multi-dimensionality of social stratification, representatives of the individualization thesis call for a first class exit of traditional class theories in view of historical changes of the welfare state resulting in a diversification of social positions and an individualization of life courses. Hence, they cast doubt not only on the homogeneity of the working class(es) but also on the postulate to study social inequality in vertical terms within work societies and national boundaries. It is argued that economic growth, improvements of individual incomes, and the growth of public and private organizations have contributed to a pervasive tertiarization of industrial society, particularly in its Western style. The concept of tertiarization will be used to indicate the combined effects of recent educational expansion, bureaucratization, and professionalization in Western societies. The major thrust of the paper is to show that these effects consist mainly of a further differentiation and hierarchization of these societies. The monopolization of the means of production, of organizational and educational resources is interpreted as leading to new tendencies toward social closure and hence to changes in the contours of traditional classes and strata. The conclusion is that beyond status and class there is no explanatory theory of social inequality in sight and that the perennial issue of destructuration of class society must be modified into one of restructuration of class society. [ABSTRACT FROM AUTHOR]