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Abstract Background The entomogenous fungus Beauveria bassiana is used as a biological insecticide worldwide, wild B. bassiana strains with high pathogenicity in the field play an important role in controlling insect pests via not only screening of highly virulent strains but also natural infection, but the pathogenicity degeneration of wild strains severely affected aforementioned effects. Previous studies have showed that multiple factors contributed to this phenomenon. It has been extensively proved that the mycovirus infection caused hypovirulence of phytopathogenic fungi, which has been used for plant disease biocontrol. However, it remains unknown whether the mycovirus epidemics is a key factor causing hypovirulence of B. bassiana naturally in the field. Methods Wild strains of B. bassiana were collected from different geographic locations in Jilin Province, China, to clarify the epidemic and diversity of the mycoviruses. A mycovirus Beauveria bassiana chrysovirus 2 (BbCV2) we have previously identified was employed to clarify its impact on the pathogenicity of host fungi B. bassiana against the larvae of insect pest Ostrinia furnacalis. The serological analysis was conducted by preparing polyclonal antibody against a BbCV2 coat protein, to determine whether it can dissociate outside the host fungal cells and subsequently infect new hosts. Transcriptome analysis was used to reveal the interactions between viruses and hosts. Results We surprisingly found that the mycovirus BbCV2 was prevalent in the field as a core virus in wild B. bassiana strains, without obvious genetic differentiation, this virus possessed efficient and stable horizontal and vertical transmission capabilities. The serological results showed that the virus could not only replicate within but also dissociate outside the host cells, and the purified virions could infect B. bassiana by co-incubation. The virus infection causes B. bassiana hypovirulence. Transcriptome analysis revealed decreased expression of genes related to insect epidermis penetration, hypha growth and toxin metabolism in B. bassiana caused by mycovirus infection. Conclusion Beauveria bassiana infected by hypovirulence-associated mycovirus can spread the virus to new host strains after infecting insects, and cause the virus epidemics in the field. The findings confirmed that mycovirus infection may be an important factor affecting the pathogenicity degradation of B. bassiana in the field.

【Objective】This study aimed to evaluate the biocontrol potential of an entomogenous fungus strain isolated from Phenacoccus solenoposis, for providing the basis of its development as a biocontrol agent.【Method】The strain was isolated and purified from the diseased P.solenoposis using tissue isolation method. Based on the cultural traits, morphological traits and phylogenetic tree analysis, its taxonomic ststus was clarified. The infection mode of strain on P.solenoposis was explored by scanning electron microscope, which clarified its ability to infect P.solenoposis. The pathogenicity of the strain to P.solenoposis was measured by leaf dipping and insect dipping method.【Result】A strain FE-1 was isolated and purified from the diseased P.solenoposis, the morphological traits results showed that the colony diameter of strain FE-1 ranged from 50 to 60 mm at 5 days on PDA medium, and the colony was orange-white in front. The conidia morphology had two types, which small type was long column shape and large spore was sickle shape. The strain FE-1 was identified as Fusarium equiseti based on cultural traits, morphological traits and phglogenetic tree analysis. The strain FE-1 infected into the insect body cavity of P.solenoposis mainly by conidia germination forming germ tubes at the epidermis for growing horizontally, and the formation of expanded appressorium at the specific contact epidermis, which clarified its ability to infect P.solenoposis. The results of indoor toxicity measuremerts showed that the pathogenicity of strain FE-1 against female adults of P.solenoposis was gradually increased with the concentration of conidial suspension. At the spore concentration of 1×108 CFU / mL, LT50 was 3.32 days, while at 7 days after inoculation, the adjusted mortality of P.solenoposis female adults was 87.50±1.79%, LC50 was 1.8×105 CFU /mL.【Conclusion】A strain FE-1 isolated and purified from the diseased P.solenoposis can form expanded appressorium at the specific contact epidermis for infection, which clarifies its ability to infect P.solenoposis. Meanwhile, the strain FE-1 is highly pathogenic against P.solenoposis, which has great potential for biocontrol and provide original material for the biocontrol research of P.solenoposis.

Background: The entomogenous fungus Beauveria bassiana is used as a biological insecticide worldwide, wild B. bassiana strains with high pathogenicity in the field play an important role in controlling insect pests via not only screening of highly virulent strains but also natural infection, but the pathogenicity degeneration of wild strains severely affected aforementioned effects. Previous studies have showed that multiple factors contributed to this phenomenon. It has been extensively proved that the mycovirus infection caused hypovirulence of phytopathogenic fungi, which has been used for plant disease biocontrol. However, it remains unknown whether the mycovirus epidemics is a key factor causing hypovirulence of B. bassiana naturally in the field. Methods: Wild strains of B. bassiana were collected from different geographic locations in Jilin Province, China, to clarify the epidemic and diversity of the mycoviruses. A mycovirus Beauveria bassiana chrysovirus 2 (BbCV2) we have previously identified was employed to clarify its impact on the pathogenicity of host fungi B. bassiana against the larvae of insect pest Ostrinia furnacalis. The serological analysis was conducted by preparing polyclonal antibody against a BbCV2 coat protein, to determine whether it can dissociate outside the host fungal cells and subsequently infect new hosts. Transcriptome analysis was used to reveal the interactions between viruses and hosts. Results: We surprisingly found that the mycovirus BbCV2 was prevalent in the field as a core virus in wild B. bassiana strains, without obvious genetic differentiation, this virus possessed efficient and stable horizontal and vertical transmission capabilities. The serological results showed that the virus could not only replicate within but also dissociate outside the host cells, and the purified virions could infect B. bassiana by co-incubation. The virus infection causes B. bassiana hypovirulence. Transcriptome analysis revealed decreased expression of genes related to insect epidermis penetration, hypha growth and toxin metabolism in B. bassiana caused by mycovirus infection. Conclusion: Beauveria bassiana infected by hypovirulence-associated mycovirus can spread the virus to new host strains after infecting insects, and cause the virus epidemics in the field. The findings confirmed that mycovirus infection may be an important factor affecting the pathogenicity degradation of B. bassiana in the field. [ABSTRACT FROM AUTHOR]

【Objective】This study aimed to evaluate the biocontrol potential of an entomogenous fungus strain isolated from Phenacoccus solenoposis, for providing the basis of its development as a biocontrol agent.【Method】 The strain was isolated and purified from the diseased P.solenoposis using tissue isolation method. Based on the cultural traits, morphological traits and phylogenetic tree analysis, its taxonomic ststus was clarified. The infection mode of strain on P.solenoposis was explored by scanning electron microscope，which clarified its ability to infect P.solenoposis. The pathogenicity of the strain to P.solenoposis was measured by leaf dipping and insect dipping method. 【Result】A strain FE-1 was isolated and purified from the diseased P.solenoposis, the morphological traits results showed that the colony diameter of strain FE-1 ranged from 50 to 60 mm at 5 days on PDA medium, and the colony was orange-white in front. The conidia morphology had two types, which small type was long column shape and large spore was sickle shape. The strain FE-1 was identified as Fusarium equiseti based on cultural traits, morphological traits and phglogenetic tree analysis. The strain FE-1 infected into the insect body cavity of P.solenoposis mainly by conidia germination forming germ tubes at the epidermis for growing horizontally, and the formation of expanded appressorium at the specific contact epidermis, which clarified its ability to infect P.solenoposis. The results of indoor toxicity measuremerts showed that the pathogenicity of strain FE-1 against female adults of P.solenoposis was gradually increased with the concentration of conidial suspension. At the spore concentration of 1×108 CFU / mL, LT50 was 3.32 days, while at 7 days after inoculation, the adjusted mortality of P.solenoposis female adults was 87.50±1.79%, LC50 was 1.8×105 CFU /mL. 【Conclusion】A strain FE-1 isolated and purified from the diseased P.solenoposis can form expanded appressorium at the specific contact epidermis for infection, which clarifies its ability to infect P.solenoposis. Meanwhile, the strain FE-1 is highly pathogenic against P.solenoposis, which has great potential for biocontrol and provide original material for the biocontrol research of P.solenoposis. [ABSTRACT FROM AUTHOR]

• The fungus Fusarium sp. LGWB-7. was isolated from the Harmonia axyridis. • Two new compounds isolated from the entomogenous fungus Fusarium sp. LGWB-7. • Beauvericin showed obvious inhibitory activity against K562 comparable to cisplatin. • Sesquiterpeniods and alkaloids are the main metabolites of Fusarium sp. LGWB-7. Two new compounds, named fusariumtrin A (1) and climacomontaninate D (2) , together with eight known ones were isolated from the rice culture of the Fusarium sp. LGWB-7, an entomogenous fungus isolated from the Harmonia axyridis. The structures of the new compounds were elucidated by the analysis of 1D and 2D spectroscopic data as well as mass spectrum (MS). Compound 10 showed cytotoxicity against K562, A549, SGC-7901, and Hela human tumor cell lines with IC 50 values of 1.46, 13.97, 9.34, and 6.64 μM, respectively. [ABSTRACT FROM AUTHOR]

Investigation of the entomogenous fungus Setosphaeria rostrate LGWB-10 from Harmonia axyridis led to the isolation of four new isocoumarin derivatives, setosphlides A–D (1–4), and four known analogues (5–8). Their planar structures and the relative configurations were elucidated by comprehensive spectroscopic methods. The absolute configurations of isocoumarin nucleus for 1–4 were elucidated by their ECD spectra. The C-10 relative configurations for the pair of C-10 epimers (1 and 2) were established by comparing the magnitude of the computed 13C NMR chemical shifts (Δδcalcd.) with the experimental 13C NMR values (Δδexp.) for the epimers. All of the isolated compounds (1–8) were evaluated for their cytotoxicities against four human tumor cell lines MCF-7, MGC-803, HeLa, and Huh-7. [ABSTRACT FROM AUTHOR]

Abstract In the present work we report the first occurrence of the entomogenous fungus Hirsutella saussurei, in the Galápagos Islands, and also the first evidence of this fungus parasitizing a new host: the invasive paper wasp Polistes versicolor. Some wasps parasitized by the fungus were found in Santa Cruz island in 2018 and 2019, while two new specimens were found in Floreana in 2019. Our data enlarge both the geographical distribution of the fungus and the host range. Even though P. versicolor is considered an important threat for the Galapagos endemic fauna, it is necessary a deep research to know if H. saussurei could be included under control programs of this invasive wasp.

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Copyright of Mycosystema is the property of Mycosystema Editorial Board and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to identify effective surfactants for Isaria fumosorosea PF904, the surface free energies of the leaves of cabbage, apple, eggplant and cucumber were measured by the OWRK method. When 4 different surfactants were added respectively into the spore suspension of Isaria fumosorosea, the surface tension and critical micelle concentration (CMC) of each solution were determined by the surface tension method. Their contact angle and maximum retention (Rm) on plant leaves were measured by angle measuring and weight difference method. Safety assessments of these screened surfactants were also conducted. The results showed that the wetting ability of Isaria fumosorosea spore suspension on 4 types of the tested plant leaves were improved when 125-500 mg/L of OFX-0193, AOS or Nekal was added. Nekal (250 mg/L) functioned best on cabbage and apple leaf surfaces(Rm: 11.90±0.23 and 13.28±0.28 mg/cm2; contact angle: 29.5°, 27.5°), indicating its advantage in promoting the wetting ability of Isaria fumosorosea PF904. OFX-0193 showed the best maximum retention at the concentration of 9.45 mg/cm2 on the surface of eggplant leaf at the concentration of 125 mg/L. Pullulan surface tension values were greater than the surface free energy values of cabbage, apple and eggplant leaves. Its contact angles were greater than 90° when reaching the concentration of CMC, which revealed that it was not effective in the activating of the wetting ability of PF904. The results of the inhibition rates of spore germination measurement showed that Nekal and OFX-0193 did not restrain Isaria fumosorosea PF904 germination, but AOS did. In conclusion, surfactants Nekal and OFX-0193 can be employed to assist Isaria fumosorosea to protect apple and cabbage from pests, OFX-0193 can also be used to control eggplant pests. [ABSTRACT FROM AUTHOR]

Copyright of Acta Edulis Fungi is the property of Acta Edulis Fungi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[Objective] The biocontrol effects of different entomogenous fungus on different stages of Tenebrio molitor were tested so as to provide a reference for biological control of stored grain insects. [Method] In dry environment with simulated grain storage, the effects of 4 strains (Metarhizium anisopliae MAX-2, Isaria fumosorosea IFK-20, Beauveria bassiana BBL-3, Isarui cicadae ICG-1 ) on 3 stages of T. molitor (larvae of 8 instars, pupa, newly emerged adults) were tested. [Result] In the environment with simulated grain storage, BBL-3 had relatively low virulence to 3 stages of insects, showing that it was not appropriate to effect in desiccation. The virulence of MAX-2 was the highest both to the larvae and the adults, IFK-20 was the second. For the pupae treated by spore suspension, the lethal speed of ICG-1 was the fastest, then MAX-2 and IFK-20. ICG-1 showed no virulence to the larvae and the adults in the environment with simulated grain storage, but its virulence could reach the highest, suggesting that some of the entomogenous fungi could keep stable virulence at different stages of insects, while some might only play an effective role at certain developmental stage of insects or in specific environment. The infective characteristics of MAX-2 against T. molitor at different stages were described, showing that its control efficacy was sustainable. Some of the infected larvae and pupa could survive as carriers, while their viability declined and some turned developmental malformation, eventually leading to death. [Conclusion] The virulence for strains of different species was significantly different and the virulence for the same strain to different stages of insects was also different. These strains except ICG-1 had good effect at different stages of T. molitor and MAX-2 showed the best sustainable efficacy to 3 stages of T. molitor, indicating hopeful application for biological control of stored grain insects. [ABSTRACT FROM AUTHOR]

A new sesquiterpene, (+)-S-1-methyl-abscisic-6-acid (1), together with five known compounds, (+)-S-abscisic acid (2), fusicoccin J (3), 3α-hydroxyfusicoccin J (4), (R)-5-hydroxymethylmellein (5) and 4-hydroxyphenethyl acetate (6) was isolated from the fermentation extract ofPhomopsis amygdali, an entomogenous fungus isolated fromCall midge. Their structures were determined mainly by analysis of MS and NMR spectroscopic data. Compounds1–6were tested for antimicrobial activity against three plant pathogenic fungi:Gibberella zeae,Verticillium albo-atrum, andFusarium nivale, and two bacteria:Escherichia coliandPseudomonas aeruginosa2033E. As a result, compounds1–4displayed antibacterial activity against Gram-negativeP. aeruginosa2033E, and the minimum inhibition concentration (MIC value) of1–4is 30 μg/mL, 58 μg/mL, 26 μg/mL, and 26 μg/mL, respectively. [ABSTRACT FROM PUBLISHER]

The fungus Metarhizium anisopliae var. acridum, strain CG 423, was tested under field conditions against the gregarious grasshopper Rhammatocerus schistocercoides (Rehn) (Orthoptera: Acrididae). Conidia formulated in a racemic mixture of soybean oil and kerosene were sprayed under field conditions using an ultralow-volume hand-held atomizer Ulva Plus adjusted to deliver 2.9 L/ha. Bands composed of 2nd instar nymphs were treated with either 5.0x10(12) or 1.0x10(13) viable conidia/ha. The number of insects in each band was estimated at day one following spraying and by the end of the field trial (15 to 16 days post-treatment). Reductions in population size reached, in average, 65.8% and 80.4% for bands treated with the higher and lower dosage, respectively. For both dosages, total mortality rates of insects collected at two days post-application, and kept in cages for 14 days under lab conditions, showed no significant differences as compared to that obtained with insects collected immediately after spraying. Healthy insects were fed to native grasses sprayed on the field with 1.0x10(13) viable conidia/ha. Mortality levels of the nymphs fed on grasses collected two and four days post-application were not affected when compared to nymphs fed on grasses collected immediately following application.

Hawaiinolides E–G ( 1 – 3 ), three additional new secondary metabolites including two cassane ( 1 and 2 ) types of diterpene lactones and one cleistanthane ( 3 ) diterpenoid, were isolated from the scale-up fermentation extract of Paraconiothyrium hawaiiense , an entomogenous fungus isolated from the Septobasidium -infected insect Diaspidiotus sp. The structures of 1 – 3 were elucidated by nuclear magnetic resonance experiments, and 1 and 3 were further confirmed by X-ray crystallography. The absolute configurations of 1 and 3 were assigned by single-crystal X-ray diffraction analysis using Cu K α radiation, whereas that of 2 was deduced via the circular dichroism data. Compound 1 showed significant cytotoxic effects against the human tumor cell line T24, with an IC 50 value (9.32 μM) comparable to that of the positive control cisplatin. [ABSTRACT FROM AUTHOR]

To investigate the host specificity of Ophiocordyceps nutans against hemipteran insects in the wild, we determined the relationship between host species and rDNA-internal transcribed spacer (ITS) variation in O. nutans. The analyzed fungal specimens infected 16 host species belonging to four families of Hemiptera. The molecular phylogenetic analysis revealed that O. nutans can be classified into two types corresponding to their host families. The genetic distance values between the two types were very remote (>0.084), and the strains of O. nutans that parasitized Halyomorpha halys and Plautia crossota stali, well-known insect pests, formed a subclade. The results suggest that O. nutans should have host specificity which can be valuable for developing biological control agents against specific hemipteran insects. [ABSTRACT FROM AUTHOR]

An inhibitor of the prophenoloxidase activation using extract from a silkworm pupa was isolated from a culture filtrate of Cordyceps militaris and identified as dipicolinic acid (DPA). The production of DPA in Clavicipitaceae fungi was examined. Entomogenous fungi that produce DPA were integrated into one group by a phylogenetic analysis based on 18S rDNA. It is suggested that the group acquired an ability to produce DPA during its evolution from plant pathogenic fungi to entomogenous fungi. [Copyright &y& Elsevier]

Producers in many North American sugarbeet (Beta vulgaris L.) growing areas rely heavily on organophosphate insecticides to manage the sugarbeet root maggot. Tetanops myopaeformis Röder. The threat of losing organophosphate options because of the potential for development of resistant root maggot strains or regulatory action has prompted a search for alternative control tools. American Type Culture Collection (ATCC) accession no. 62176, a strain of the entomopathogenic fungus Metarhizium anisopliae (Metschnikoff) Sorokin, was studied in field trials as a bioinsecticidal option for control of T. myopaeformis larvae because of shown virulence in preliminary laboratory testing. The fungus was evaluated at four field sites during 2001 and 2002 as a planting-time granule, an aqueous postemergence spray, or a combination of both. Three rates of M. anisopliae conidia, 4 × 1012 (1×), 8 × 1012 (2×), and 1.6 × 1013/ha (4×) were applied as granules, and the spray was tested at the 1× rate. A significant linear response in sucrose yield in relation to M. anisopliae granule application rate confirmed its entomopathogenic capacity raider field conditions. Each multiple of M. anisopliae granules applied .affected a yield increase of ≈171 kg sucrose/ha. The fungus was less effective than conventional insecticides at preventing stand loss from high root maggot infestations early in the season. It is concluded that, with additional research, mycoinsecticides could potentially be incorporated into management systems to complement chemical control tactics such as insecticidal seed treatments, soil insecticides (possibly at reduced rates), or postemergence materials for integrated control of T myopaeformis adults or larvae. [ABSTRACT FROM AUTHOR]

In order to reveal the differences between Cordyceps, Paecilomyces (= Isaria) and Nomuraea, we collected seven entomogenous fungi grown in natural field and analyzed the profiles of water-soluble constituents derived from some different sources of Cordyceps, Paecilomyces and Nomuraea by determination using capillary electrophoresis. C. sinensis and C. kyushuensis showed similar peak clusters of protein migrated at 5–7, 8–9, and 12–20 min. The peak clusters obtained from N. atypicola was similar to those of C. sinensis and C. kyushuensis. The water-soluble constituent clusters of C. militaris migrated at 5–9 and 10–15 min were partly different from those of other Cordyceps. It was also revealed that the P. tenuipes and P. cicadae showed lesser peak clusters rather than Cordyceps. These results indicated that the profiles of protein of these entomogenous fungi by capillary electrophoretic analysis could serve as fingerprints for classification and medicinal quality control of Cordyceps. [ABSTRACT FROM AUTHOR]

A trypsin-like protease, P-1-1, was purified from the culture supernatant of the fungus Cordyceps militaris by (NH4)2SO4 precipitation, chromatography on DEAE Bio-Gel Agarose, TSKgel CM-5PW, and gel-filtration with HiLoad 26/60 Superdex 75 pg, and its properties were examined. Purified P-1-1 showed a single band by SDS-PAGE and was estimated to have a molecular mass of 23,405 by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). The optimum pH of the enzyme was between 8.5 and 12.0. It was inhibited strongly by leupeptin and diisopropyl fluorophosphate (DFP), and definitely did by N α-tosyl-L-lysine chloromethyl ketone hydrochloride (TLCK), phenylmethanesulfonyl fluoride (PMSF) and chymostatin. The carbonyl group sides of Arg and Lys were confirmed as the sites of cleavage by the enzyme toward cecropin B. These results indicate that P-1-1 is a trypsin-type serine protease. The N-terminal amino acid sequence of P-1-1 showed a high homology with those of trypsins or chymotrypsin derived from Diptera insects. [Copyright &y& Elsevier]

Cordyceps owariensis f. viridescens forma nov. (Nom. Jap., Amami-yarinohosemitake) is described from an underground nymph of Platypleura kuroiwae collected in Amami-oshima Island, southwestern Japan. Cultural isolations were made from ascospores of the fresh material of this fungus, and consequently a new hyphomycete was developed as its anamorph. Nomuraea owariensis is described to accommodate this anamorphic state. This is the first report on the association of a Nomuraea anamorph with cicadicolous Cordyceps species. [ABSTRACT FROM AUTHOR]

Three new sesquiterpenoids, peniterpenoids A − C (1 – 3), together with six known metabolites (4 – 9) were isolated from an entomogenous fungus Penicillium janthinellum (LB1.20090001) collected from a wheat cyst nematode. The structures of the new compounds were elucidated based on NMR and HRESIMS spectroscopic analyses. The absolute configuration of the C-8 secondary alcohol of peniterpenoid B (2) was determined by [Rh 2 (OCOCF 3) 4 ]-induced ECD experiment. Subsequently, the antimicrobial and DPPH scavenging activities were determined. Compounds 6 – 8 exhibited moderate antibacterial activities against Staphylococcus aureus (CGMCC1.2465) with MIC values of 25.0, 50.0 and 12.5 μg/mL, respectively. Unlabelled Image [ABSTRACT FROM AUTHOR]

An illustrated scheme of the life cycle of Entomophthora virulenta shows that an alternation of the conidal and resting spore stages is involved. The resting spores are azygospores; chlamydospores are also present. [ABSTRACT FROM AUTHOR]

The objective of the present study was to investigate the optimal nutritional requirements for mycelial growth and sporulation of entomopathogenic fungus Aschersonia aleyrodis Webber by orthogonal layout methods. Herein the order of effects of nutrient components on mycelial growth was tryptone > Ca(2+) > soluble starch > folacin, corresponding to the following optimal concentrations: 1.58% Soluble Starch, 3.16% Tryptone, 0.2 mmol l(-1) Ca(2+) and 0.005% Folacin. The optimal concentration of each factors for sporulation was 1.16% lactose, 0.394% tryptone, 0.4 mmol l(-1) Fe(2+) and 0.00125% VB1, and the effects of medium components on sporulation were found to be in the order lactose > VB1 > Fe(2+) > tryptone. Under the optimal culture conditions, the maximum production of mycelial growth achieved 20.05 g l(-1) after 7 days of fermentation, while the maximum spore yield reached 5.23 ×10(10) spores l(-1) after 22 days of cultivation. This is the first report on optimization of nutritional requirements and design of simplified semi-synthetic media for mycelial growth and sporulation of A. aleyrodis.