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[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]

Graphical abstract Highlights • Strongwellsea from 15 dipteran hosts were strongly associated with host species. • Strongwellsea genotypes infecting seven species from Anthomyiidae formed a monophyletic lineage. • Strongwellsea genotypes infecting four species from Muscidae clustered at different places. • All infections in three Fannidae species were caused by the same genotype of Strongwellsea magna. • Based on host species, conidial morphology and phylogeny, the genus Strongwellsea contains several undescribed species. Abstract The genus Strongwellsea (Entomophthorales) has a unique pathobiology. Infected adult dipteran hosts develop a large hole in their abdomens, through which conidia are actively discharged while the hosts are still alive. We analyzed the IST II region of Strongwellsea from 29 infected hosts representing 15 dipteran species from Anthomyiidae, Fanniidae, Muscidae, and Scathophagidae. Each genotype was found on only one host species or a few closely related host species. Strongwellsea genotypes infecting flies from Anthomyiidae represented a monophyletic lineage, including the species Strongwellsea castrans , while genotypes infecting Muscidae were very diverse and clustered at different places. All three host species from Fanniidae were infected with the same Strongwellsea genotype, namely the species Strongwellsea magna. It appears that members of the genus Strongwellsea are strongly adapted to their host species and have co-evolved. [ABSTRACT FROM AUTHOR]

[Display omitted] • Two new species from the fungal genus Strongwellsea (Entomophthorales) are described. • Strongwellsea selandia infects adult Helina evecta (Diptera). • Strongwellsea gefion infects adult Helina reversio (Diptera). • The two new species differ from other described species from the genus. • Differences include morphology of spores, genetic identity, and host species. Two new species from the genus Strongwellsea (Entomophthorales: Entomophthoraceae) that infect adult flies from the genus Helina (Muscidae) are described: Strongwellsea selandia Eilenberg & Humber infecting adult Helina evecta (Harris), and Strongwellsea gefion Eilenberg & Humber infecting adult Helina reversio (Harris). The descriptions are based on pathobiological, phenotypical and genotypical characters. The new species differ from other described members from the genus Strongwellsea by a) pathobiology as revealed by natural host species, b) morphology of primary conidia, c) color of resting spores, and d) genotypical clustering based on analysis of ITS2. The two new species have only been documented from North Zealand, Denmark. [ABSTRACT FROM AUTHOR]

In temperate regions, insect pathogenic fungi face the challenge of surviving through the winter. Winter is a time when hosts are immobile, low in number or are present in a stage which is not susceptible to infection. Fungi from Entomophthoromycota have so far been known to survive the winter in two ways: either as (1) thick-walled resting spores released into environment from dead hosts, or as (2) structures inside the dead host (e.g., hyphal bodies). Here we report, from the Danish environment, a third way to survive the winter, namely a slow progression and transmission of Entomophthora schizophorae in adult dipteran Pollenia hosts that hibernate in clusters in unheated attics, sheltered areas outdoors (under bark etc.). Fungus-killed sporulating flies were observed outside very early and very late in the season. By sampling adults at the time of their emergence from hibernation in late winter/early spring we documented that the fungus was naturally prevalent and killed flies after a period of incubation. Experimentally we documented that even at the low temperature of 5 °C, the fungus was able to maintain itself in Pollenia cohorts for up to 90 days. From these observations the full winter cycle of this fungus is elucidated. The three types of winter survival are discussed in relation to fungus epidemic development. [ABSTRACT FROM AUTHOR]

Strongwellsea crypta Eilenberg & Humber. [Display omitted] • Strongwellsea crypta is a new species infecting its dipteran host adult Botanophila fugax. • The description includes symptoms on the infected host, and morphology of spores. A new species from the genus Strongwellsea (Entomophthorales: Entomophthoraceae) is described: Strongwellsea crypta Eilenberg & Humber from adult Botanophila fugax (Meigen) (Diptera: Anthomyiidae). The description is based on pathobiological, phenotypical and genotypical characters. The abdominal holes in infected hosts develop rapidly and become strikingly large and edgy, almost rhomboid in shape. The new species S. crypta differs from S. castrans, the only described species infecting flies from Anthomyiidae, by: (a) naturally infecting another host species, (b) by having significantly longer primary conidia, and (c) by genotypical clustering separately from that species when sequencing ITS2. [ABSTRACT FROM AUTHOR]

1 Weevil larvae of the genus Otiorhynchus are a serious problem in agriculture and forestry, causing damage to a wide range of plant species, primarily by larval feeding on roots. Otiorhynchus larvae are a serious pest in forest plantations in Iceland, causing 10–20% mortality of newly-planted seedlings. 2 We studied the effects of soil fungi on the survival of Otiorhynchus sulcatus larvae. The larvae were introduced into pots with birch seedlings grown in: (i) nursery peat; (ii) nursery peat inoculated with three different species of ectomycorrhizal fungi; (iii) nursery peat inoculated with insect pathogenic fungi; (iv) nursery peat inoculated with ectomycorrhizal fungi and insect pathogenic fungi; and (v) nursery peat inoculated with natural forest soil from Icelandic birch woodland. 3 Larval survival was negatively affected by inoculation of: (i) the ectomycorrhizal fungus Laccaria laccata; (ii) the ectomycorrhizal fungus Cenococcum geophylum; (iii) the insect pathogenic fungus Metarhizium anisopliae; and (iv) forest soil. Inoculation with the ectomycorrhizal fungus Phialophora finlandia did not have any significant effect on larval survival. No significant synergistic effect was found between insect pathogenic and ectomycorrhizal fungi. 4 It is concluded that ectomycorrhizal and insect pathogenic fungi have a significant potential in biological control of Otiorhynchus larvae in afforestation areas in Iceland. Further studies are needed to establish the effect of these fungi in the field and to analyse how mycorrhizal fungi affect root-feeding larvae. [ABSTRACT FROM AUTHOR]

Abstract: We present novel findings highlighting the early effects of inoculation of downy birch (Betula pubescens Ehrh.) seedlings with factorial combinations of beneficial soil fungi, namely, ectomycorrhizal and insect pathogenic fungi, on Otiorhynchus spp. larval root herbivory under Icelandic field conditions. Birch seedlings were pre-treated with (1) a mixture of four ectomycorrhizal fungal species: Paxillus involutus (Batsch: Fr.) Fr., Telephora terrestris Ehrh.: Fr., Phialophora finlandia Wang & Wilcox. and Hebeloma sp., (2) the insect pathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin or (3) a combined inoculum that included the four ectomycorrhizal fungal species and M. anisopliae. Non-inoculated seedlings served as untreated controls. Inoculated and control seedlings were transplanted into soils at three different sites representing eroded land, birch woodland and heathland. Assessment following the first growing season indicated that the effects on Otiorhynchus spp. larval root herbivory and seedling productivity of pre-inoculation with the ectomycorrhizal fungal species mixture and the insect pathogenic fungus, M. anisopliae, were highly dependent on site and treatment. Inoculation with ectomycorrhizal fungi and M. anisopliae significantly reduced root herbivory in both the birch woodland and, in particular, the eroded land sites. In the heathland site, no or even negative effects on root herbivory were observed. However, potential synergistic effects of combined inoculation with both ectomycorrhizal fungi and M. anisopliae were not identified under these experimental conditions. Accumulated seedling mortality ascribed to root herbivory after three growing seasons showed a significant site dependent response, but no significant treatment effect was detected. The effects of ectomycorrhizal and insect pathogenic fungi on root herbivory are discussed and we conclude that significant, although mostly unidentified, interactions between the inoculated fungi and the naturally occurring soil microorganisms may explain these findings. Such interactions require further detailed investigation in order to develop an efficient strategy for soil inoculation with beneficial fungi. [Copyright &y& Elsevier]

Three DNA regions (ITS 1, LSU rRNA and GPD) of isolates from the insect-pathogenic fungus genus Entomophthora originating from different fly ( Diptera) and aphid ( Hemiptera) host taxa were sequenced. The results documented a large genetic diversity among the fly-pathogenic Entomophthora and only minor differences among aphid-pathogenic Entomophthora. The evolutionary time of divergence of the fly and the aphid host taxa included cannot account for this difference. The host-driven divergence of Entomophthora, therefore, has been much greater in flies than in aphids. Host-range differences or a recent host shift to aphid are possible explanations. [ABSTRACT FROM AUTHOR]

Abstract: It is increasingly recognized that the biodiversity in agroecosystems deliver significant ecosystem services to agricultural production such as biological control of pests. Entomopathogenic fungi, specifically the anamorphic taxa Beauveria bassiana and Metarhizium anisopliae, Hypocreales (Ascomycota), are among the natural enemies of pests in agroecosystems and the fungi are candidates for future conservation biological control in temperate regions. Conservation biological control is a biological control strategy in which farming practices and environmental manipulations are adopted to enhance the living conditions for specific natural enemies of pests. However, in order to manipulate the environment for the benefit of populations of the entomopathogens, knowledge of fundamental aspects of the ecology of the fungi considered is necessary. This knowledge is still scarce despite the large bulk of recent research into inoculation and inundation biological control with these fungi. Here, we review the current knowledge of the ecology of indigenous populations of B. bassiana and M. anisopliae in agroecosystems of temperate regions, primarily Europe and North America. We suggest anamorphic life cycles of B. bassiana and M. anisopliae in these regions based on the literature of their natural occurrence and distribution in agroecosystems, population dynamics, and interactions with other organisms, environmental factors, and agronomical practices. [Copyright &y& Elsevier]

Abstract: By baiting soil samples with larvae of Galleria mellonella detailed surveys of the occurrences of entomopathogenic fungi were conducted over two consecutive years in the soil of an organically farmed field (17.1ha) and the associated hedgerow. Samples were collected at specific points (at distances of 25m) based on Geographical Information Systems (GIS) and sample point coordinates were relocated by Global Positioning System (GPS). In the agricultural field soil Beauveria bassiana was the most common fungus while Paecilomyces fumosoroseus was most common in soil from the hedgerow. Significant clustering of B. bassiana in the agricultural field was found in one of the two years. High and low densities of B. bassiana were subsequently confirmed within selected areas by reducing distances between sample points. The results demonstrated the suitability of the sampling method for identifying distribution patterns of soil borne entomopathogenic fungi and the importance of large sample sizes to describe local biodiversity of the fungi in the soil environment. [Copyright &y& Elsevier]

Abstract: A leaf imprinting technique combined with a selective medium was used to document the natural occurrence of Beauveria bassiana on phylloplanes of typical hedgerow plants (grasses, stinging nettle and hawthorn) in May, July and September in a hedgerow in Denmark. The density of B. bassiana (as measured by numbers of colony forming units) was greatest in September and on lower nettle leaves. B. bassiana was isolated from phylloplanes in a different hedgerow the following year and a similar picture of occurrence was found. Genetic diversity of selected in vitro isolates were characterised by Universally Primed (UP) PCR, and 13 distinguishable banding patterns were found at the two localities. Of these, four were shared between the field sites and all plant species harboured isolates of B. bassiana with at least two different banding patterns. The isolation method described represents a valuable tool for studying naturally occurring B. bassiana and for rapid isolation of indigenous strains of the fungus for future development of biocontrol agents. The significance of the findings for the life-cycle of B. bassiana is discussed. [Copyright &y& Elsevier]

A method for baiting soil samples with Delia floralis larvae was developed, and a systematic survey was conducted on soils from northern Norway for insect pathogenic fungi, using D. floralis and Galleria mellonella larvae as bait. The occurrence of insect pathogenic fungi in soils from arable fields and adjacent field margins of conventionally and organically managed farms was compared. The study showed a significantly higher occurrence of insect pathogenic fungi in soils from arable fields of organically managed farms. No significant differences in the occurrence of insect pathogenic fungi were, however, found between the field margins of the two cropping systems. Fungal species identified in the study were Beauveria bassiana, Fusarium merismoides, Metarhizium anisopliae and Tolypocladium cylindrosporum. T. cylindrosporum was found more frequently when using D. floralis as the bait insect than when using G. mellonella. [Copyright &y& Elsevier]

[Display omitted] • Laboratory infection bioassay with conidia shower from Pandora sp. nov. mycelial mat. • The entomopathogen infects insect families Psyllidae and Triozidae. • Survival times of fruit crop pests are significantly reduced after inoculation. • No interaction between phytoplasma infection of vector, host plant and the fungus. • Pandora sp. nov. has high potential to become a biocontrol agent for vector control. A new but still unpublished entomopathogenic fungus (ARSEF13372) in the genus Pandora (Entomophthorales: Entomophthoraceae) was originally isolated from Cacopsylla sp. (Hemiptera: Psyllidae). Several species of the genus Cacopsylla vector phloem-borne bacteria of the genus ' Candidatus Phytoplasma', which cause diseases in fruit crops such as apple proliferation, pear decline and European stone fruit yellows. To determine Pandora 's host range and biocontrol potential we conducted laboratory infection bioassays; Hemipteran phloem-feeding insects were exposed to conidia actively discharged from in vitro produced mycelial mats of standardized area. We documented the pathogenicity of Pandora sp. nov. to species of the insect families Psyllidae and Triozidae, namely Cacopsylla pyri L., C. pyricola (Foerster), C. picta (Foerster, 1848), C. pruni (Scopoli), C. peregrina (Foerster), and Trioza apicalis Foerster. The occurrence of postmortem signs of infection on cadavers within 10 days post inoculation proved that Pandora sp. nov. was infective to the tested insect species under laboratory conditions and significantly reduced mean survival time for C. pyri (summer form and nymph), C. pyricola , C. picta , C. pruni , C. peregrina and T. apicalis. Assessing a potential interaction between phytoplasma, fungus and insect host revealed that phytoplasma infection (' Candidatus Phytoplasma mali') of the vector C. picta and/or its host plant apple Malus domestica Borkh. did not significantly impact the survival of C. picta after Pandora sp. nov. infection. The results from infection bioassays were discussed in relation to Pandora sp. nov. host range and its suitability as biocontrol agent in integrated pest management strategies of psyllid pests, including vector species, in orchards. [ABSTRACT FROM AUTHOR]

[Display omitted] • In Brazilian strawberry soil, M.robertsii was the most abundant species. • M. brunneum was the most abundant species in Denmark. • 17 Metarhizium haplotypes were determined. • We found a higher Shannon's diversity index in organically managed soils. Studies on community composition and population structure of entomopathogenic fungi are imperative to link ecosystem functions to conservation biological control. We studied the diversity and abundance of Metarhizium spp. from soil of conventionally and organically farmed strawberry crops and from the adjacent field margins in two different climatic zones: Brazil (tropical) and Denmark (temperate), using the same isolating methods. In Brazilian strawberry soil, Metarhizium robertsii (n = 129 isolates) was the most abundant species, followed by M. humberi (n = 16); M. anisopliae (n = 6); one new taxonomically unassigned lineage Metarhizium sp. indet. 5 (n = 4); M. pingshaense (n = 1) and M. brunneum (n = 1). In Denmark, species composition was very different, with M. brunneum (n = 33) being isolated most commonly, followed by M. flavoviride (n = 6) and M. pemphigi (n = 5), described for the first time in Denmark. In total, 17 haplotypes were determined based on MzFG543igs sequences, four representing Danish isolates and 13 representing Brazilian isolates. No overall difference between the two climatic regimes was detected regarding the abundance of Metarhizium spp. in the soil in strawberry fields and the field margins. However, we found a higher Shannon's diversity index in organically managed soils, confirming a more diverse Metarhizium community than in soils of conventionally managed agroecosystems in both countries. These findings contribute to the knowledge of the indigenous diversity of Metarhizium in agricultural field margins with the potential to contribute to pest regulation in strawberry cropping systems. [ABSTRACT FROM AUTHOR]

• Two new species from the genus Strongwellsea are described from dipteran hosts. • Strongwellsea tigrinae was found on the host Coenosia tigrina (Muscidae) • Strongwellsea acerosa was found on the host Coenosia testaceae. • The circumscription of the genus Strongwellsea is emended. Two new species from the genus Strongwellsea (Entomophthorales: Entomophthoraceae) are described: Strongwellsea tigrinae from adult Coenosia tigrina (Diptera: Muscidae) and Strongwellsea acerosa from adult Coenosia testacea. The descriptions are based on pathobiological, phenotypical and genotypical characters. Further, the circumscription of the genus Strongwellsea is emended. Our findings suggest that Strongwellsea harbors a high number of species, of which now only five have been described. [ABSTRACT FROM AUTHOR]

• We described two types of actively discharged secondary conidia in species from the insect pathogenic fungus genus Strongwellsea. • Ellipsoid type secondary conidia are broadly ellipsoidal with a clearly pointed basal papilla. • Subglobose type secondary conidia are subglobose to almost bell-shaped with a flattened papilla. Two types of secondary conidia and their formation are described from six species of Strongwellsea infecting hosts from Anthomyiidae, Muscidae and Fanniidae. We used a simple device allowing secondary conidia to be produced under very moist or comparatively dry conditions. Ellipsoid type s econdary conidia , which are formed under very moist conditions, have never been reported before from the genus Strongwellsea , and they are unique for Entomophthorales; these are broadly ellipsoidal with a clearly pointed basal papilla and are actively discharged. Subglobose type secondary conidia are, for the first time, described from several species in the genus Strongwellsea ; they are subglobose to almost bell-shaped with a flattened papilla and are actively discharged. Subglobose type secondary conidia are formed under more dry conditions. A general pattern of the formation of secondary conidia in Strongwellsea and the ecological roles of primary conidia and of the two types of secondary conidia are discussed. [ABSTRACT FROM AUTHOR]

In this special issue the focus is on the factors and (molecular) mechanisms that determine the transmission efficiency of a variety of insect pathogens in a number of insect hosts. In this editorial, we summarize the main findings of the twelve papers in this special issue and conclude that much more needs to be learned for an in-depth understanding of pathogen transmission in field and cultured insect populations. Analyses of mutual interactions between pathogens or between endosymbionts and pathogens, aspects rather under-represented in the scientific literature, are described in a number of contributions to this special issue. [ABSTRACT FROM AUTHOR]

Opportunistic bacteria are often ubiquitous and do not trigger disease in insects unless the conditions are specifically favorable for bacterial development in a suitable host. In this paper, we isolated and identified a bacterium, Pseudomonas aeruginosa, from the larvae of the giant mealworm Zophobas morio and we studied the possible entry routes by challenging larvae with per os injection and subdermal injection. We also evaluated the effect of exposing groups of larvae to P. aeruginosa inoculated in their feed and the effect of exposing wounded larvae to P. aeruginosa. We concluded that the mortality rate of Z. morio larvae is higher when P. aeruginosa gets in direct contact with the hemolymph via intracoelomic injection compared to a situation where the bacterium is force-fed. Larvae with an open wound exposed to P. aeruginosa presented higher mortality rate compared to larvae with a wound that was not exposed to the bacterium. We documented too, that cannibalism and scavenging were more prevalent among larvae in a group, when P. aeruginosa is present compared to when it is absent. We discuss hereby different aspects related with the pathogen's entry routes to insects the complexity of pathogen´s transmission in high population densities and different ways to prevent and/or control P. aeruginosa in mass rearing systems. [ABSTRACT FROM AUTHOR]

The fungus Metarhizium anisopliae is a facultative insect pathogen used as biological control agent of several agricultural pests worldwide. It is a dimorphic fungus that is able to display two growth morphologies, a filamentous phase with formation of hyphae and a yeast-like phase with formation of singlecelled blastospores. Blastospores play an important role for M. anisopliae pathogenicity during disease development. They are formed solely in the hemolymph of infected insects as a fungal strategy to quickly multiply and colonize the insect's body. Here, we use comparative genome-wide transcriptome analyses to determine changes in gene expression between the filamentous and blastospore growth phases in vitro to characterize physiological changes and metabolic signatures associated with M. anisopliae dimorphism. Our results show a clear molecular distinction between the blastospore and mycelial phases. In total 6.4% (n = 696) out of 10,981 predicted genes in M. anisopliae were differentially expressed between the two phases with a fold-change. 4. The main physiological processes associated with up-regulated gene content in the single-celled yeast-like blastospores during liquid fermentation were oxidative stress, amino acid metabolism (catabolism and anabolism), respiration processes, transmembrane transport and production of secondary metabolites. In contrast, the up-regulated gene content in hyphae were associated with increased growth, metabolism and cell wall re-organization, which underlines the specific functions and altered growth morphology of M. anisopliae blastospores and hyphae, respectively. Our study revealed significant transcriptomic differences between the metabolism of blastospores and hyphae. These findings illustrate important aspects of fungal morphogenesis in M. anisopliae and highlight the main metabolic activities of each propagule under in vitro growth conditions. [ABSTRACT FROM AUTHOR]

The generalist entomopathogenic fungus, Metarhizium brunneum, has proved to have great potential as a versatile biological pest control agent. The gall midge Aphidoletes aphidimyza is a specialist predator that occurs naturally in Europe and has been successfully used for aphid suppression. However, the interaction between these two biological control organisms and how it may affect the biological control of aphids awaits further investigation. As part of the EU-supported project INBIOSOIL, this study was conducted in greenhouse conditions to assess the possible effects of combining both biological control agents. In a randomized complete block design, sweet corn (Zea mays var. saccharata) plants were grown in large pots filled with natural soil or natural soil inoculated with M. brunneum. At the third leaf stage, before being individually caged, plants were infested with Rhopalosiphum padi and A. aphidimyza pupae were introduced in the soil. Aphidoletes aphidimyza midge emergence, number of living midges and number of aphids were recorded daily. The presence of conidia in the soil and on leaves was assessed during the experiment. At the conclusion of the experiment, the number of live aphids and their developmental stage, consumed aphids, and A. aphidimyza eggs was assessed under stereomicroscope. This study’s findings showed that the presence of M. brunneum did not affect A. aphidimyza midge emergence. However, longevity was significantly affected. As the study progressed, significantly fewer predatory midges were found in cages treated with M. brunneum compared to untreated cages. Furthermore, by the end of the study, the number of predatory midges found in the Metarhizium-treated cages was four times lower than in the untreated cages. Both daily and final count of aphids were significantly affected by treatment. Aphidoletes aphidimyza applied alone suppressed the aphid population more effectively than M. brunneum applied alone. Additionally, the aphid population was most suppressed when both agents were combined, though the suppression was less than additive. [ABSTRACT FROM AUTHOR]

Obligate parasites are under strong selection to increase exploitation of their host to survive while evading detection by host immune defences. This has often led to elaborate pathogen adaptations and extreme host specificity. Specialization on one host, however, often incurs a trade-off influencing the capacity to infect alternate hosts. Here, we investigate host adaptation in two morphologically indistinguishable and closely related obligate specialist insect-pathogenic fungi from the phylum Entomophthoromycota, Entomophthora muscae sensu stricto and E. muscae sensu lato, pathogens of houseflies ( Musca domestica) and cabbage flies ( Delia radicum), respectively. We compared single nucleotide polymorphisms within and between these two E. muscae species using 12 RNA-seq transcriptomes from five biological samples. All five isolates contained intra-isolate polymorphisms that segregate in 50:50 ratios, indicative of genetic duplication events or functional diploidy. Comparative analysis of dN/ dS ratios between the multinucleate E. muscae s.str. and E. muscae s.l. revealed molecular signatures of positive selection in transcripts related to utilization of host lipids and the potential secretion of toxins that interfere with the host immune response. Phylogenetic comparison with the nonobligate generalist insect-pathogenic fungus Conidiobolus coronatus revealed a gene-family expansion of trehalase enzymes in E. muscae. The main sugar in insect haemolymph is trehalose, and efficient sugar utilization was probably important for the evolutionary transition to obligate insect pathogenicity in E. muscae. These results support the hypothesis that genetically based host specialization in specialist pathogens evolves in response to the challenge of using resources and dealing with the immune system of different hosts. [ABSTRACT FROM AUTHOR]

Among fungi from the order Entomophthorales (Entomophthoromycota), there are many specialized, obligatory insect-killing pathogens. Pandora formicae (Humber & Bałazy) Humber is a rare example of an entomophthoralean fungus adapted to exclusively infect social insects: wood ants from the genus Formica . There is limited information available on P. formicae ; many important aspects of this host-pathogen system remain hitherto unknown, and the taxonomical status of the fungus is unclear. Our study fills out some main gaps in the life history of P. formicae , such as seasonal prevalence and overwintering strategy. Field studies of infection prevalence show a disease peak in late summer and early autumn. Typical thick-walled entomophthoralean resting spores of P. formicae are documented and described for the first time. The proportion of cadavers with resting spores increased from late summer throughout autumn, suggesting that these spores are the main overwintering fungal structures. In addition, the phylogenetic status of Pandora formicae is outlined. Finally, we review the available taxonomical literature and conclude that the name P. formicae should be used rather than the name P. myrmecophaga for ant-infecting fungi displaying described morphological features. [ABSTRACT FROM AUTHOR]

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]

We studied the bee specialist fungus Ascosphaera in wild solitary bees to investigate the diversity of the genus in nature and the ecology of these fungi with their bee hosts. A new morphologically distinctive species was discovered which also has a unique nrITS sequence. This new species, here named Ascosphaera callicarpa, is common on the larval feces of the solitary bee Chelostoma florisomne which nests in the Phragmites reeds of thatched roofs in Europe. Because collections of Ascosphaera from wild bees are scarce and because little is known about the ecology and distribution of the majority of the species in the genus, a key to the species thus far reported for Europe is included. [ABSTRACT FROM AUTHOR]

The natural occurrence of entomophthoralean fungi pathogenic towards aphids on cereal and potato crops was investigated in the years 2009, 2010, and 2011. Infected aphids were sampled in three bioclimatic zones in Tunisia (Beja, Cap bon, and Kairouan) and fungal species were determined based on morphological characters such as shape, size, and number of nuclei in the primary conidia. Polymerase Chain Reaction (PCR) on the internal transcribed spacer 1 region (ITS1) was used to verify morphological determination. Both methods gave consistent results and we documented for the first time the natural occurrence of two fungal species from the order Entomophthorales (phylum Entomophthoromycota), Pandora neoaphidis and Entomophthora planchoniana. Both fungi were recorded on the aphid species Sitobion avenae and Myzus persicae on barley ears and potato leaves, respectively. Moreover, natural mixed infections by both species (P. neoaphidis and E. planchoniana) were documented on the target aphids. This investigation provides basic information of entomopathogenic fungi infecting economically important aphids in Tunisia. [ABSTRACT FROM AUTHOR]

Knowledge of the occurrence, distribution and diversity of pathogens of insects and arachnids (entomopathogens) in the Arctic is very limited. Climate change is expected to affect Arctic terrestrial arthropod communities and therefore also host-pathogen interactions, given that entomopathogens are present. We conducted a survey of fungal entomopathogens in soil samples collected at four localities in Greenland; two at low Arctic sites (Ritenbenk and Disko Island) and two at sites in the high Arctic (Zackenberg and Danmarkshavn). Fungi were isolated from soil samples using larvae of the insect species Galleria mellonella (Lepidoptera) and Tenebrio molitor (Coleoptera) as baits providing evidence that the fungal isolates were indeed entomopathogenic. Five fungal species (Ascomycota; Hypocreales) were found: Isaria fumosorosea Wize, Isaria farinosa (Holmsk.) Fr., Beauveria bassiana (Bals.) Vuill., Beauveria pseudobassiana Rehner and Humber and Tolypocladium inflatum W. Gams (syn. = T. niveum). I. farinosa was found at all four localities, while I. fumosorosea was detected in single samples at each of three localities including both high Arctic sites. Only the locality on Disko Island revealed B. bassiana, whereas B. pseudobassiana was isolated at the three other sites. T. inflatum was only found on Disko Island and only isolated with T. molitor as a bait insect. The results document that fungal entomopathogens are widely distributed in the soil environment in Greenland. Entomopathogens should therefore be included in future studies of arthropod ecology in the Arctic. [ABSTRACT FROM AUTHOR]

Ascosphaera subglobosa (Eurotiomycetes: Onygenales) is newly described from the pollen provisions and nesting material of the solitary leaf-cutting bee Megachile rotundata in Canada and the western United States. This new species, related to A. atra and A. duoformis, is distinguished from other Ascosphaera species by its globose to subglobose ascospores, evanescent spore balls and unique nuclear ribosomal DNA sequences (ITS and LSU). [ABSTRACT FROM AUTHOR]

Abstract: The below- and aboveground communities of fungal entomopathogens (Ascomycota: Hypocreales) were investigated in an experimental conventional and organic vegetable cropping system over two seasons in Denmark. The experimental design allowed for evaluating differences between farming practices in the occurrence of soil-borne fungal entomopathogens and as natural infections aboveground in arthropod hosts. Belowground, Metarhizium anisopliae dominated the agricultural field with Beauveria bassiana, Metarhizium flavoviride, and Isaria fumosorosea being present at lower frequencies. Abundances of M. anisopliae were not different between conventional and organic soils. Aboveground, B. bassiana was the most common fungal entomopathogen in arthropod host cadavers. Infections of M. flavoviride, Isaria farinosa, and Gibellula spp. were also recorded. Most mycosed cadavers were recovered in August and September from conventionally farmed plots. Cadaver sizes ranged from 1.9 to 23.6mm with means of 3.7–4.1mm. Among host functional groups, predators dominated (47–63%) over herbivores, parasitoids, and nectar-feeders. No occurrence of M. anisopliae was recorded among >200 mycosed cadavers aboveground. The results therefore suggest that M. anisopliae is not involved in direct below- and aboveground interactions in the investigated agroecosystem. Conservation biological control strategies targeting M. anisopliae should thus be solely for controlling soil-dwelling pests in temperate regions as this fungus is unlikely naturally to infect aboveground hosts in the agroecosytem. [Copyright &y& Elsevier]

Abstract: Recent studies have shown that the entomopathogenic fungus Beauveria bassiana occurs naturally on the phylloplanes of several plants, including nettles. Insects could, by their activity, be contributing to this inoculum by dispersing it from other sites. The potential of nettle aphids Microlophium carnosum and their predator Anthocoris nemorum to disperse conidia of B. bassiana from soil to nettles and from sporulating cadavers in the nettle canopy was investigated in laboratory experiments. In petri dish assays, aphids showed potential to distribute B. bassiana from soil to nettle leaves. Predators dispersed inoculum from both soil and cadavers to nettle leaves in petri dishes. In microcosms, aphids did not disperse B. bassiana from the soil or from cadavers confined in the canopy, but A. nemorum were able to transfer inoculum from soil into the nettle canopy and to distribute conidia from cryptic cadavers. In some instances, infections were initiated in aphids and predators as a consequence of dispersal. [Copyright &y& Elsevier]

Abstract: Entomopthora muscae sensu lato is a complex of morphologically similar fungal species pathogenic to evolutionarily advanced flies (Cyclorrhapha). To reach an operational species definition and recognition of species within this complex, the values of host range, morphological and genetic characteristics are reconsidered. Within the E. muscae species complex morphological and nuclear characteristics of the primary conidia are taxonomically important. In this study we compared the dimensions and nuclear numbers of the primary conidia of isolates from their original (natural) hosts and after being transferred to alternative hosts (cross-transmission) in order to check the stability of these characteristics. The conidial characteristics change substantially when produced in alternative host species, but their overall range in variability still fit within the traditional morphological species circumscriptions. The phylogenetic analyses of the ITS II and LSU rRNA gene sequences, revealed three distinct lineages within the complex: E. schizophorae, E. muscae and E. syrphi. Within each of these lineages sequence divergence was seen between isolates originating from different host species. Our studies on the physiological host range showed that several isolates were able to infect alternative dipteran species. Musca domestica was a particularly good receptor. The ecological host range of any individual isolate seems, however, to be limited to one host species evidenced by the occurrence of distinct genotypes within each natural infected host species shown by RAPD. The high host specificity of these fungi emphasizes the importance of identifying the host taxon at species level in the recognition of Entomophthora species. We recommend that morphological characteristics of fungal structures and host taxon, together with molecular data, serve as criteria for species determination in future studies on members of the E. muscae complex. [Copyright &y& Elsevier]

The plasmid pHT73 containing cry1Ac and tagged with an erythromycin resistance gene was transferred from Bacillus thuringiensis subspecies kurstaki KT0 to several Bacillus cereus group strains by conjugation. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE) and phase contrast microscopy showed that the transconjugants containing plasmid pHT73 could express Cry1Ac toxin and produce bipyramidal crystalline inclusion bodies during sporulation. The study demonstrated that pHT73 could be transferred to B. thuringiensis subsp. kurstaki, several B. cereus strains and Bacillus mycoides. Under non-selective conditions, the stability of the pHT73 plasmid in the transconjugants was found to be 58.2–100% after 100 generations and 4–96% after 200 generations. The variations are mainly caused by the choice of receptor strain. [Copyright &y& Elsevier]

The present research addressed spray-drying and air-drying techniques applied to Metarhizium robertsii blastospores to develop wettable powder (WP) formulations. We investigated the effect of co-formulants on blastospore viability during drying and assessed the wettability and stability of formulations in water. The effect of oxygen-moisture absorbers was studied on the shelf life of these formulations stored at 26 °C and 4 °C for up to 90 days. Additionally, we determined the virulence of the best spray-dried and air-dried formulations against the corn leafhopper Dalbulus maidis. While sucrose and skim milk played an essential role as osmoprotectants in preserving air-dried blastospores, maltodextrin, skim milk, and bentonite were crucial to attain high cell survival during spray drying. The lowest wettability time was achieved with spray-dried formulations containing less Ca-lignin, while charcoal powder amount was positively associated with formulation stability. The addition of oxygen-moisture absorbers inside sealed packages increased from threefold to fourfold the half-life times of air-dried and spray-dried formulations at both storage temperatures. However, the half-life times of all blastospore-based formulations were shorter than 3 months regardless of temperature and packaging system. Spray-dried and air-dried WP formulations were as virulent as fresh blastopores against D. maydis adults sprayed with 5 × 107 blastospores mL−1 that induced 87.8% and 70.6% mortality, respectively. These findings bring innovative advancement for M. robertsii blastospore formulation through spray-drying and underpin the importance of adding protective matrices coupled to oxygen-moisture absorbers to extend cell viability during either cold or non-refrigerated storage. Key points: • Cost-effective wettable powder formulations of M. robertsii blastospores were developed. • Bioefficacy of formulations against the corn leafhopper was comparable to fresh blastospores. • Cold storage and dual oxygen-moisture absorber are critical for extended shelf life. [ABSTRACT FROM AUTHOR]

The influence of clone and morph on the infection of Sitobion avenae with Erynia neoaphidis was examined in laboratory assays. The LC[sub 50]-values were low; green alates: 0.8–1.8, green apterae: 2.9, brown alates: 1.5 and brown apterae: 2.6–3.6 conidia mm[sup -2]. Within each of the two inoculation occasions, alates of both clones were significantly more susceptible than apterae, while there was no difference between the two clones. The LT[sub 50]-values at 18°C varied between 6.4 and 7.5 days and there was no significant difference in LT[sub 50]-values between either the two different coloured clones or between alates and apterae. [ABSTRACT FROM AUTHOR]

Three species within the Entomophthora muscae (Cohn) Fresenius complex (Entomophthora schizophorae Keller & Wilding, E. muscae s.str., and E. muscae "group B") were investigated for resting spore formation in vivo in the house fly (Musca domestica L.). Resting spores of E. muscae group B were experimentally induced from August to the beginning of February, while no resting spores were ever observed in E. schizophorae infected M. domestica or in flies infected by E. muscae s.str. originating from M. domestica. When newly dead fly cadavers containing E. muscae group B resting spores were kept moist, cystidia emerged from the abdomen; this is the first report of cystidia in the genus Entomophthora. Resting spore production was significantly affected by both temperature and E. muscae group B strain. More infected flies formed resting spores when kept 1 week at 10°C compared with constant exposure at 22°C, but the tendency of the different E. muscae group B strains to form resting spores persisted with shifting temperatures. After 4 months of incubation under natural winter conditions in Denmark, E. muscae group B resting spores germinated on water agar at 20°C with a 16 h light : 8 h dark photoperiod within 1 week, but no germ conidia were observed.Key words: Entomophthorales, Entomophthora muscae complex, Diptera, Musca domestica, resting spore formation, resting spore germination.Les auteurs ont examiné, chez la mouche de maison (Musca domestica L.), la formation in vivo des spores de repos de trois espèces du complexe Entomophthora muscae (Cohn) Fresenius (Entomophthora schizophorae Keller & Wilding, E. muscae, s.str., et E. muscae "groupe B"). Les auteurs ont induit expérimentalement la formation de spores de repos de l'E. muscae groupe B, à partir du mois d'août jusqu'en février, alors qu'aucune spore de repos n'a jamais été observée chez les M. domestica infectées par l'E. schizophorae, ou chez des mouches infectées par l'E. muscae s.str., provenant de M. domestica. Lorsque qu'on maintient humide des cadavres de mort récente, contenant des spores de repos de l'E. muscae groupe B, des cystides émergent de l'abdomen; il s'agit de la première mention de cystides pour le genre Entomophthora. La production des spores de repos est significativement affectée à la fois par la température et par la souche d'E. muscae groupe B. Un plus grand nombre de mouches infectées forment des spores de repos lorsqu'on les maintient à 10°C pendant une semaine comparativement à une exposition constante à 22°C, mais la tendance des différentes souches de l'E. muscae groupe B à former des spores de repos persiste avec des températures changeantes. Après 4 mois d'incubation sous les conditions hivernales naturelles du Danemark, les spores de l'E. muscae groupe B germent sur eau gélosée à 20°C et sous une photopériode de 16 h : 8 h L:O, en moins d'une semaine, sans qu'on puisse observer de conidies de germination.Mots clés : Entomophthorales, complexe Entomophthora muscae, Diptères, Musca domestica, formation de spores de repos, germination de spores de repos.[Traduit par la Rédaction] [ABSTRACT FROM AUTHOR]

Simple Summary: The white-spotted longicorn beetle, Anoplophora malasiaca, is one of the most destructive pests of many fruits and street trees. Effective controls are needed because the effect of marketed insecticides is limited. Entomopathogenic fungi offer a solution, combination with the beetles' contact sex pheromone. The surface of the female body is covered with contact sex pheromone, which we extracted. Males held onto a glass model coated with female extract for 5 h, but males held onto one without extract for <0.3 h. Males that held onto coated model, attached to fabric impregnated with an entomopathogenic fungus, Beauveria brongniartii, picked up significant fungi. The fungi were then transferred to females during mating. Our results indicate that a combination of contact pheromone with a pathogen could improve entomopathogenic infection of both male and female beetles. The white-spotted longicorn beetle, Anoplophora malasiaca, is one of the most destructive pests of horticultural crops and street trees. Effective controls are needed because the effect of marketed insecticides is limited. Entomopathogenic fungi offer a solution, and improving the rate of infection would be a breakthrough in this beetle's control. The combination of pathogenic fungi and the beetle's contact sex pheromone was suggested. The surface of the female body is covered with contact sex pheromone, which elicit male mating behavior. To develop a method for the practical control of this beetle, we evaluated the arrestant activity of female extract containing contact pheromone coated on a black glass model. Males presented with a coated model held on for 5 h (mean) during an 8-h experiment. In contrast, males presented with a control model held on for <0.3 h. Males that held onto coated models attached to fabric impregnated with conidia of the fungus Beauveria brongniartii picked up much conidia, which they then passed on to females during mating. [ABSTRACT FROM AUTHOR]

Gall midges are important pests in many crops. In fruit, they are difficult to control due to their life cycle, which takes place partially within the fruit. Here, we provide the first successful laboratory experiment to infect pear gall midge (Contarinia pyrivora) with the insect pathogenic fungus Metarhizium brunneum. We developed a procedure for sampling larvae, maintaining them in the laboratory and subjecting them to the fungus. We demonstrated that dipping larvae in a fungus suspension or adding a fungus suspension to the soil result in significant fungus induced mortality of the pear gall midge. An immune response in treated larvae was recorded proving that there was a real pathogenesis. Finally, we discuss next steps and a strategy for field experiments. [ABSTRACT FROM AUTHOR]

Black soldier fly [BSF; Hermetia illucens L. (Diptera: Stratiomyidae)] larvae are very effective in transforming low‐grade food waste into valuable high‐end proteins and fat, in intensive production facilities. The production output of this species is growing quickly, but upscaling brings risks to the health status of the reared insects. Until now, not a single major case of disease outbreak caused by a pathogen in a BSF production unit has been reported. This contrasts with data on other species of mass‐produced insects, which have experienced various disease outbreaks, indicating that BSFs are comparatively resistant to insect diseases. Further, there are no records of natural infections caused by entomopathogens in BSF. In this review, the known entomopathogens of Diptera, especially BSF, and their potential risks for causing disease in these insects are summarized. [ABSTRACT FROM AUTHOR]

In contrast, AHT requires 1) a living host and 2) host behavior that facilitates pathogen transmission, thereby increasing pathogen fitness at the expense of host fitness (Fig 1). To achieve these ends, AHT pathogens must produce transmissible reproductive structures while still allowing the host some level of functionality, which is a major distinction between AHT and most other entomopathogenic fungi, in which infectious spores (conidia) are not produced until after host death. Many fungi from the subphylum Entomophthoromycotina are so highly specialized for life on their preferred insect hosts that they can be cultivated beyond a vegetative stage outside of their host only with difficulty (or even not at all), making laboratory studies on transmission, host behavior, etc. based on fungi produced in vitro difficult. The existence of cyclic AHT infections in diverse insect species suggests that this lifestyle is an effective means of transmission for these host-specific fungal pathogens regardless of whether or not these host-parasite systems are easy to observe. [Extracted from the article]

The cosmopolitan entomopathogenic and root endophytic fungus Metarhizium robertsii has a versatile lifestyle and during liquid fermentation undergoes a dimorphic transformation from hyphae to conidia or microsclerotia, or from hyphae to blastospores. In all cases, these processes are mediated by environmental and nutritional cues. Blastospores could be used in spray applications to control arthropod pests above ground and may serve as an attractive alternative to the traditional solid-grown aerial conidial spores of Metarhizium spp. found in commercial products. Nitrogen is a vital nutrient in cell metabolism and growth; however, it is the expensive component in liquid cultures of entomopathogenic fungi. Our goals in this study were to optimize nitrogen sources and titers for maximum production of M. robertsii blastospores cultured in shake flasks at highly aerated conditions and to further determine their virulence against the corn leafhopper Dalbulus maidis, an important vector of serious pathogens in maize crops worldwide. Our fermentation studies revealed that the low-cost corn steep liquor (CSL) was the most suitable nitrogen source to improve blastospore growth in M. robertsii. The growth kinetic assays determined the optimal titer of 80 g L−1 and a yield up to 4.7 × 108 cells mL−1 within 5 days of cultivation (3 days preculture and 2 days culture), at a total cost of US$0.30 L−1. Moreover, the blastospore growth kinetic was strongly dependent on glucose and nitrogen consumptions accompanied by a slight drop in the culture pH. Insect bioassays evidenced a high virulence of these blastospores, either as dried or fresh cells, to D. maidis adults fed on maize plants. Our findings provide insights into the nutritional requirements for optimal and cost-efficient production of M. robertsii blastospores and elucidate the potential of blastospores as an ecofriendly tool against the corn leafhopper. [ABSTRACT FROM AUTHOR]

Entomophthoralean fungi are insect pathogenic fungi and are characterized by their active discharge of infective conidia that infect insects. Our aim was to study the effects of temperature on the discharge and to characterize the variation in the associated temporal pattern of a newly discovered Pandora species with focus on peak location and shape of the discharge. Mycelia were incubated at various temperatures in darkness, and conidial discharge was measured over time. We used a novel modification of a statistical model (pavpop), that simultaneously estimates phase and amplitude effects, into a setting of generalized linear models. This model is used to test hypotheses of peak location and discharge of conidia. The statistical analysis showed that high temperature leads to an early and fast decreasing peak, whereas there were no significant differences in total number of discharged conidia. Using the proposed model we also quantified the biological variation in the timing of the peak location at a fixed temperature. [ABSTRACT FROM AUTHOR]

The European Union (EU) has recently published its first list of invasive alien species (IAS) of EU concern to which current legislation must apply. The list comprises species known to pose great threats to biodiversity and needs to be maintained and updated. Horizon scanning is seen as critical to identify the most threatening potential IAS that do not yet occur in Europe to be subsequently risk assessed for future listing. Accordingly, we present a systematic consensus horizon scanning procedure to derive a ranked list of potential IAS likely to arrive, establish, spread and have an impact on biodiversity in the region over the next decade. The approach is unique in the continental scale examined, the breadth of taxonomic groups and environments considered, and the methods and data sources used. International experts were brought together to address five broad thematic groups of potential IAS. For each thematic group the experts first independently assembled lists of potential IAS not yet established in the EU but potentially threatening biodiversity if introduced. Experts were asked to score the species within their thematic group for their separate likelihoods of i) arrival, ii) establishment, iii) spread, and iv) magnitude of the potential negative impact on biodiversity within the EU. Experts then convened for a 2‐day workshop applying consensus methods to compile a ranked list of potential IAS. From an initial working list of 329 species, a list of 66 species not yet established in the EU that were considered to be very high (8 species), high (40 species) or medium (18 species) risk species was derived. Here, we present these species highlighting the potential negative impacts and the most likely biogeographic regions to be affected by these potential IAS. We identified 66 species, that are currently absent from the EU, which pose a very high, high or medium threat to biodiversity and ecosystems. The species span a range of functional groups, with primary producers being numerically dominant. Escape from confinement is the pathway considered to be the most likely route of introduction for many species, particularly among plants and vertebrates. [ABSTRACT FROM AUTHOR]

We provide insights into how the interactions of two entomopathogenic fungi and a virus play a role in virulence, disease development, and pathogen reproduction for an economically important insect crop pest, the sugarcane borer Diatraea saccharalis (Fabricius) (Lepidoptera: Crambidae). In our model system, we highlight the antagonistic effects of the co-inoculation of Beauveria bassiana and granulovirus (DisaGV) on virulence, compared to their single counterparts. By contrast, combinations of Metarhizium anisopliae and B. bassiana, or M. anisopliae and DisaGV, have resulted in additive effects against the insect. Intriguingly, most cadavers that were derived from dual or triple infections, produced signs/symptoms of only one species after the death of the infected host. In the combination of fungi and DisaGV, there was a trend where a higher proportion of viral infection bearing conspicuous symptoms occurred, except when the larvae were inoculated with M. anisopliae and DisaGV at the two highest inoculum rates. Co-infections with B. bassiana and M. anisopliae did not affect pathogen reproduction, since the sporulation from co-inoculated larvae did not differ from their single counterparts. [ABSTRACT FROM AUTHOR]

According to the Convention on Biological Diversity, by 2020 invasive alien species (IAS) should be identified and their impacts assessed, so that species can be prioritized for implementation of appropriate control strategies and measures put in place to manage invasion pathways. For one quarter of the IAS listed as the '100 of the world's worst' environmental impacts are linked to diseases of wildlife (undomesticated plants and animals). Moreover, IAS are a significant source of 'pathogen pollution' defined as the human-mediated introduction of a pathogen to a new host or region. Despite this, little is known about the biology of alien pathogens and their biodiversity impacts after introduction into new regions. We argue that the threats posed by alien pathogens to endangered species, ecosystems, and ecosystem services should receive greater attention through legislation, policy, and management. We identify 10 key areas for research and action, including those relevant to the processes of introduction and establishment of an alien pathogen and to prediction of the spread and associated impact of an alien pathogen on native biota and ecosystems. The development of interdisciplinary capacity, expertise, and coordination to identify and manage threats was seen as critical to address knowledge gaps. [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]

• Yeast-like cells from solid and liquid media have similar virulence. • Yeast-like cells of Metarhizium rileyi express specific genes related to virulence. • Yeast-like cells grown on solid medium express unique genes. • Few up-regulated orthologous genes in common between M. rileyi and M. anisopliae yeast-like cells. • Many unknown protein-coding genes up-regulated in the yeast-like cells from solid medium. Metarhizium rileyi is an entomopathogenic fungus with a narrow host range which distinguishes it from other Metarhizium species with broad host ranges. This species is also unique because the initial yeast-like growth on solid media is only observed in liquid culture in other Metharizium species. A lack of knowledge about the metabolism and genetic signatures of M. rileyi during this yeast-like phase on solid and in liquid media is a bottleneck for its large-scale production as a commercial biocontrol agent. In this study we found that M. rileyi yeast-like cells produced on solid medium infected and killed the important insect pest Spodoptera frugiperda with comparable efficiency as yeast-like cells grown in liquid medium. Secondly, we used comparative transcriptomic analysis to investigate the active genes and genomic signatures of the M. rileyi yeast-like morphotypes produced on solid and in liquid media. Yeast-like cells grown in liquid medium had upregulated genes relating specifically to signal transduction and particular membrane transporters. Thirdly, we compared the transcriptomic profiles of yeast-like phases of M. rileyi with those of M. anisopliae. The yeast-like phase of M. rileyi grown on solid medium upregulated unique genes not found in other Metarhizium species including specific membrane proteins and several virulence factors. Orthologous genes associated with heat shock protein, iron permease, membrane proteins and key virulence traits (e.g. collagen-like protein Mcl1) were upregulated in both species. Comparative transcriptome analyses of gene expression showed more differences than similarities between M. anisopliae and M. rileyi yeast-like cells. [ABSTRACT FROM AUTHOR]

Establishment, persistence and local dispersal of the entomopathogenic fungi Metarhizium anisopliae (ESALQ1037) and M. robertsii (ESALQ1426) (Ascomycota: Hypocreales) were investigated in the soil and rhizosphere following soil drench application in strawberries between 2012 and 2013 at a single location in Inconfidentes, Minas Gerais, Brazil. Metarhizium spp. isolates (n = 108) were collected using selective agar media and insect bait methods, and characterized by sequence analyses of the 5’–end of the translation elongation factor 1-α and the MzFG543igs intergenic region and by multilocus simple sequence repeat analysis. Both applied fungal isolates were frequently recovered from bulk soil and rhizosphere samples of the treated plots, suggesting that they were able to establish and disperse within the soil. Persistence within the soil and strawberry rhizosphere for both fungal isolates was observed up to 12 months after application with frequencies of 25% of haplotypes similar to isolate ESALQ1037 and 87.5% of haplotypes similar to isolate ESALQ1426, respectively. Overall, M. robertsii was the most abundant species in the agroecosystem studied representing 77.8% of the isolates recovered across all sample dates. [ABSTRACT FROM AUTHOR]

Metarhizium spp. have recently been shown to be associated with the roots of different plants. Here we evaluated which Metarhizium species were associated with roots of oat ( Avena sativa ), rye ( Secale cereale ) and cabbage ( Brassica oleracea ), common crop plants in Denmark. Thirty-six root samples from each of the three crops were collected within an area of approximately 3 ha. The roots were rinsed with sterile water, homogenized and the homogenate plated onto selective media. A subset of 126 Metarhizium isolates were identified to species by sequencing of the 5′ end of the gene translation elongation factor 1-alpha and characterized by simple sequence repeat (SSR) analysis of 14 different loci. Metarhizium brunneum was the most common species isolated from plant roots (84.1% of all isolates), while M. robertsii (11.1%) and M. majus (4.8%) comprised the remainder. The SSR analysis revealed that six multilocus genotypes (MLGs) were present among the M. brunneum and M. robertsii isolates, respectively. A single MLG of M. brunneum represented 66.7%, 79.1% and 79.2% of the total isolates obtained from oat, rye and cabbage, respectively. The isolation of Metarhizium spp. and their MLGs from roots revealed a comparable community composition as previously reported from the same agroecosystem when insect baiting of soil samples was used as isolating technique. No specific MLG association with a certain crop was found. This study highlights the diversity of Metarhizium spp. found in the rhizosphere of different crops within a single agroecosystem and suggests that plants either recruit fungal associates from the surrounding soil environment or even govern the composition of Metarhizium populations. [ABSTRACT FROM AUTHOR]

Pandora formicae is an obligate entomopathogenic fungus from the phylum Entomophthoromycota, known to infect only ants from the genus Formica . In the final stages of infection, the fungus induces the so-called summit disease syndrome, manipulating the host to climb up vegetation prior to death and fixing the dead cadaver to the surface, all to increase efficient spore dispersal. To investigate this fascinating pathogen–host interaction, we constructed interaction transcriptome libraries from two final infection stages from the material sampled in the field: (1) when the cadavers were fixed, but the fungus had not grown out through the cuticle and (2) when the fungus was growing out from host cadaver and producing spores. These phases mark the switch from within-host growth to reproduction on the host surface, after fungus outgrowth through host integument. In this first de novo transcriptome of an entomophthoralean fungus, we detected expression of many pathogenicity-related genes, including secreted hydrolytic enzymes and genes related to morphological reorganization and nutrition uptake. Differences in expression of genes in these two infection phases were compared and showed a switch in enzyme expression related to either cuticle breakdown or cell proliferation and cell wall remodeling, particularly in subtilisin-like serine protease and trypsin-like protease transcripts. [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]