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Due to their versatile lifestyle as saprophytes, endophytes and entomopathogens, fungi of the genera Metarhizium and Beauveria are exposed to varying illumination conditions in their natural habitats, which makes a thorough adaptation to light very likely. While the few available studies for these genera support this assumption, research in this field is still in its infancy and the data material restricted to only a few fungal species. Thus, the aim of this work was to explore how light influences growth, conidial production and secondary metabolite formation of two industrial relevant strains of M. brunneum (MA 43, formerly M. anisopliae var. anisopliae BIPESCO 5/F52) and B. brogniartii (BIPESCO 2). To achieve this, we constructed an easily adjustable illumination device for highly standardized photophysiological studies of fungi on Petri dishes, the so-called LIGHT BOX. With the aid of this device, M. brunneum and B. brongniartii were grown on S4G or S2G agar at 25°C for 14 days either in complete darkness or under constant illumination with red light (λpeak = 635 nm), green light (λpeak = 519 nm) or blue light (λpeak = 452 nm). In addition, for each wavelength the effect of different illumination intensities was tested, i.e., intensities of red light ranging from 22.1 ± 0.1 to 136.5 ± 0.3 µW cm-², green light from 16.5 ± 0.1 to 96.2 ± 0.1 µW cm-², and blue light from 56.1 ± 0.2 to 188.9 ± 0.6 µW cm-². Both fungi strongly responded in terms of growth, conidial production, pigmentation and morphology to changes in the wavelength and irradiation intensity. The wavelength-dependent production of the well-known secondary metabolite oosporein which is secreted by the genus Beauveria in particular, was also increased under green and blue light exposure. The established LIGHT BOX system allows not only to optimize spore production yields with these biotechnologically relevant fungi, but also allows the photobiological exploration of other fungi.

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.

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.

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.

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