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Pandora sp. nov. inedit. (ARSEF13372) is a recently isolated entomophthoralean fungus with high potential for psyllid pest control. The use of entomopathogenic fungi as biocontrol agents in large-scale field application requires biomass production in a sufficient quantity and quality. This work is the first attempt to explore the biomass production of the novel entomophthoralean Pandora species in a liquid medium. This study aims at establishing a submerged fermentation process with potential for mass production of the fungus. Three different complex nutrient sources were evaluated for maximising biomass in a liquid shaking culture. Pandora sp. nov. grew best in media containing skimmed milk, but even faster in a mixture of skimmed milk, yeast extract and a low-cost protein hydrolysate from animal by-products. Subsequently, the produced biomass can be encapsulated in biopolymer beads or granules in order to transfer the fungus into an easily applicable form. Therefore, growth as finely dispersed mycelium was promoted by increased media osmolality through the addition of sodium chloride. After the medium had been transferred to a stirred tank bioreactor with a working volume of 8 L, a maximum biomass dry weight of 21 g·L−1 was reached after 48 h. These promising results can pave the way for large-scale fermentation and formulation processes of this novel Pandora species for biological psyllid pest control. [ABSTRACT FROM AUTHOR]

BACKGROUND Pandora sp. nov. inedit. (Entomophthorales: Entomophthoraceae) (ARSEF 13372) is a recently isolated entomophthoralean fungus with potential for psyllid pest control. This study aimed to develop a formulation based on biocompatible hydrogel beads in order to transfer the fungus into an easily applicable form and to test the effects on psyllids. RESULTS: After encapsulation in calcium alginate beads, Pandora sp. nov. grew from the beads and discharged conidia over 12 days under optimal humidity conditions at 18 °C. Conidial number was increased 2.95‐fold by the addition of skimmed milk as nutritional formulation adjuvant to the beads. The virulence of the encapsulated fungus was assessed with the two target psyllid species; the summer apple psyllid, Cacopsylla picta and the pear psyllid, Cacopsylla pyri. Beads containing skimmed milk as nutritional adjuvant led to the highest mortalities (48.3% on C. picta and 75.0% on C. pyri). In a second bioassay, survival time of C. pyri exposed to beads containing different concentration (10%, 20% or 40%) of Pandora sp. nov. was tested. The survival time of C. pyri was significantly reduced when exposed to beads containing 10% or 20% Pandora sp. nov. The median survival time was reached after 5–6 days past inoculation and the cumulative mortality for C. pyri treated with Pandora sp. nov. beads showed up to 89% mortality. CONCLUSION: The promising results of this study will ease the way for large‐scale field application of a novel Pandora species in biological psyllid pest control. [ABSTRACT FROM AUTHOR]

[Display omitted] The new species Pandora cacopsyllae Eilenberg, Keller & Humber (Entomophthorales) is described. The fungus was found on infected pear psyllids Cacopsylla pyri (Hemiptera: Psyllidae) in a pear orchard in Zealand, Denmark. Morphological structures (conidia, rhizoids, cystidia) were described on the designated type host C. pyri. In addition, conidia from an in vitro culture were described. Pandora cacopsyllae differs from other Pandora species by a) C. pyri is the natural host; b) conidia are different from other Pandora species infecting Psylloidea; c) ITS differs from other Pandora species infecting Hemiptera. The fungus has a high potential for future use in biological control of Cacopsylla pest species as well as other psyllids. [ABSTRACT FROM AUTHOR]

A two-year field study using a blend of entomopathogens in conjunction with chemical insecticides was carried out to determine to which extent they affect western corn rootworm (WCR), Diabrotica virgifera virgifera , survival, maize root damages, and grain yield and to assess the potential for side-effects on natural arthropod enemies. The products tested were conducted on a maize crop and included maize seeds dressed with the neonicotinoid clothianidin (Poncho™), Belem™ (ai: cypermethrin), dianem™ (entomopathogenic nematode: Heterorhabditis bacteriophora ), and a granular formulation of the insect pathogenic fungus Metarhizium brunneum . Trials were conducted at four (2014) and two (2015) sites heavily infested with WCR in the Southeast of Styria, Austria. The lowest number of WCR adults were recorded in 2015 at sites where the nematode and fungal biocontrol agents were used with clothianidin dressed maize seeds. The treatments did not significantly influence plant lodging and grain yield compared with the untreated (negative) control. The WCR population density rose during the investigation period and the average number of beetles in all treatments and in both study years far exceeded the stipulated economic threshold value for continuous maize of around one beetle per plant. Non-target evaluation using pitfall traps did not show any significant impact of the treatments on the abundance or diversity of indigenous predatory beetles and spiders. The lack of damage suggests that the WCR threshold is considerably higher than the stipulated economic threshold under favourable growing conditions, but a systematic crop rotation is recommended as an integral part of the WCR management both as a prophylaxis and as a background for the best treatment. [ABSTRACT FROM AUTHOR]

The entomopathogenic fungal Metarhizium anisopliae lineage harbors cryptic diversity and was recently split into several species. Metarhizium spp. are frequently isolated from soil environments, but the abundance and distribution of the separate species in local communities is still largely unknown. Entomopathogenic isolates of Metarhizium spp. were obtained from 32 bulked soil samples of a single agroecosystem in Denmark using Tenebrio molitor as bait insect. To assess the Metarhizium community in soil from the agricultural field and surrounding hedgerow, 123 isolates were identified by sequence analysis of 5′ end of elongation factor 1-α and their genotypic diversity characterized by multilocus simple sequence repeat (SSR) typing. Metarhizium brunneum was most frequent (78.8%) followed by M. robertsii (14.6%), while M. majus and M. flavoviride were infrequent (3.3% each) revealing co-occurrence of at least four Metarhizium species in the soil of the same agroecosystem. Based on SSR fragment length analysis five genotypes of M. brunneum and six genotypes of M. robertsii were identified among the isolates. A single genotype within M. brunneum predominated (72.3% of all genotypes) while the remaining genotypes of M. brunneum and M. robertsii were found at low frequencies throughout the investigated area indicating a diverse Metarhizium community . The results may indicate potentially favorable adaptations of the predominant M. brunneum genotype to the agricultural soil environment. [ABSTRACT FROM AUTHOR]