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The original Bacillus subtilis was isolated from the soil of an apple orchard, and B. subtilis strain BS80-6, selected from Bacillus subtilis by ion implantation , was used as an antagonist for postharvest biological control against apple anthracnose (colletotrichum gloeosporioides). The mechanisms of action and efficacy of Bacillus subtilis strain BS80-6 against apple anthracnose caused by colletotrichum gloeosporioides were studied in vitro and on apples in controlled and semi-commercial conditions. An application of cell suspension (108 cells per mL) of the antagonist in artificial wounds of apples reduced growth of C. gloeosporioides after storage at different temperatures. The inhibitory actions of cell culture to hyphal growth and to spores germination were 86.6% and 98.65% , respectively, and the control efficacy of cell culture against the disease was 60.34% at room temperature. The results showed that BS80-6 was more effective against apple anthracnose. The cell culture of BS80-6 received better control efficacy against apple anthracnose than culture filtrates and autoclaved cell. All treatments significantly inhibited the disease both in vitro and in vivo compared with control. Fruits treated with cell culture and stored at 10 °C had lower infection rate, more delayed formation of acervwlus and smaller lesion diameter than those stored at 20 °C. There was better control efficacy in fruits inoculated with spores after application of BS80-6. The mechanisms of BS80-6 activity appeared to involve production of an antifungal substance, deformation of hyphal cell and disintegration of cell wall. Besides, BS80-6 could improve the activity of major defense enzymes of apple, such as peroxidase (POD) and polyphenol oxidase (PPO). [ABSTRACT FROM AUTHOR]

Field survey of the entomopathogenic fungusBeauveria bassianain association with the red turpentine beetle,Dendroctonus valens, was undertaken in three pine plantations in Northern China. In total, 88 strains ofB. bassiana sensu latowere isolated from the soil, bark, beetle frass, living adult and cadaver samples and soil was proved to be an important inoculum reservoir for fungal entomopathogens. Of these, 77 isolates were included for genetic diversity analysis by PCR for inter-simple sequence repeats (ISSR). Genetic diversity and population structure analysis of the isolates from three sites and five niches demonstrated high genetic diversity and heterogeneity between and/or within populations. Wright's statistics revealed a high gene flow rate (4.529) among the three populations, especially among the soil-derived isolate subpopulations. Low variation was mainly caused (94.8%) by variation among different substrates, suggesting the importance of microhabitat substrates on genetic diversity ofB. bassiana. Phylogenetic variation was not associated with geographic distance. [ABSTRACT FROM AUTHOR]

Abstract: In the knowledge engineering, the fuzzy conceptual graphs and the production rule are two important knowledge representation methods. Because the confidence information can’t be represented in the fuzzy conceptual graphs and the fuzzy knowledge can’t be represented in the production rules, the ability of their knowledge representation is grievous insufficiency. In this paper, the extended production rule which is a new knowledge representation method has been presented. In the extended production rule, the antecedent and consequent of a rule are represented by fuzzy conceptual graphs, and the sustaining relation between antecedent and consequent is the confidence. The rule combines the fuzzy knowledge with the confidence effectually. It not only retains the semantic plentifulness of facts and proposition, but also makes the reasoning results more effectively. According to the extended production rule, the uncertain reasoning algorithm based on fuzzy conceptual graphs is designed. By the experiment test and analysis, the reasoning effects of the extended production rule are more in reason. The researching results are applied in the designed of uncertain inference engine in fuzzy expert system. [Copyright &y& Elsevier]

Three field experiments using cages were conducted in Anhui, China, to test the efficacy of entomopathogenic fungi against adult Asian longhorned beetles, Anoplophora glabripennis (Motschulsky). The use of two commercially available Beauveria spp. strains, Beauveria bassiana (Balsamo) Vuillemin and Beauveria brongniartii (Saccardo) Petch, applied as cultures in fiber bands fastened around tree trunks, was compared with trunk sprays in the first cage experiment. Longevity of A. glabripennis was decreased by both strains compared with controls, with females killed earlier by B. brongniartii than by B. bassiana. This decrease in longevity was independent of the application method used. In addition, oviposition scars per cage and daily oviposition rate per female were also reduced by both strains, showing a sublethal effect of the entomopathogens. After 10 d, conidial viability was still high on the bands but was drastically reduced when the strains were sprayed onto tree trunks. In the second cage experiment, four strains, proven to be highly pathogenic in the laboratory, were applied as bands alone. During the second cage experiment, daily temperatures were much higher and relative humidities were much lower than during the first cage experiment, and these conditions probably reduced fungal pathogenicity and decreased the sublethal oviposition reduction effect. It was demonstrated that one other B. bassiana strain and one Metarhizium anisopliae (Metchnikoff) Sorokin strain reduced male A. glabripennis longevity. None of the four strains tested had any significant effect on A. glabripennis when applied as 15-d-old bands in a third field experiment. [ABSTRACT FROM AUTHOR]

Summary Triplicate molecular methods, i.e. polymerase chain reaction-restriction fragment length polymorphism of the pr 1 gene, microsatellite markers and 28S rDNA haplotyping by detecting the presence or absence of group I introns, were used for population study of the entomopathogenic fungus, Beauveria bassiana . The findings showed that the average genetic diversity index of geographical populations was significantly smaller than that of populations derived from insect host orders, indicating that the genetic relatedness of B. bassiana strains was highly associated with geographical locality rather than insect host species. The reproductive style of all the B. bassiana populations was found to be non-clonal. Population structure analysis revealed that the average divergent coefficient among populations of B. bassiana was far below 1 (0.1112), which indicated that there was no significant genetic differentiation between populations, and that the overall genetic diversity mainly resulted from the genetic variations within geographical populations. Statistically, genetic distances between populations were positively correlated with geographical distances, suggesting that geographical separation poses an obstacle to the possibility and frequency of genetic exchanges between populations. On the other hand, gene flow was indirectly established to occur between B. bassiana populations. [ABSTRACT FROM AUTHOR]

Describes the teleomorph of entomopathogenic fungus Beauveria bassiana. Discovery of the genus Beauveria; Physical characteristics; Type locality and host; Anatomic description.

The genus Samsoniella was erected based on orange cylindrical to clavate stromata, superficial perithecia and conidiophores with Isaria -like phialides and to segregate them from the Akanthomyces group. In this study, based on morphological features and multigene (SSU, LSU, TEF , RPB1 and RPB2 ) phylogenetic analysis six Samsoniella species parasitizing spiders were collected in China. Three of them belong to known species S.alpina , S.erucae and S.hepiali . Three new species S.anhuiensis sp. nov. , S.aranea sp. nov. and S.fusiformispora sp. nov. are illustrated and described. They are clearly distinct from other species in Samsoniella occurring in independent subclades. Furthermore, among the four insect-pathogenic fungi specimens collected from similar sites, three of them were identified as the new species described below. Our study significantly broadens the host range of Samsoniella from Insecta to Arachnida, marking a noteworthy expansion in understanding the ecological associations of these fungi. Additionally, the identification of both mononematous and synnematous conidiophores in our study not only expands the knowledge of Samsoniella species but also provides a basis for future research by comparing the ecological significance between these conidiophore types. In conclusion, our study enhances the understanding of Samsoniella diversity, presenting a refined phylogenetic framework and shedding light on the ecological roles of these fungi in spider parasitism., Competing Interests: The authors have declared that no competing interests exist., (Ting Wang, Jun Li, Xiaoyun Chang, Zengzhi Li, Nigel L. Hywel-Jones, Bo Huang, Mingjun Chen.)

The entomopathogenic fungus, Beauveria bassiana, is commonly used as a biological agent for pest control. Environmental and biological factors expose the fungus to oxidative stress; as a result, B. bassiana has adopted a number of anti-oxidant mechanisms. In this study, we investigated metabolites of B. bassiana that are formed in response to oxidative stress from hydrogen peroxide (H2O2) by using a liquid chromatography mass spectrometry (LC-MS) approach. Partial least-squares discriminant analysis (PLS-DA) revealed differences between the control and the H2O2-treated groups. Hierarchical cluster analysis (HCA) showed 18 up-regulated metabolites and 25 down-regulated metabolites in the H2O2-treated fungus. Pathway analysis indicated that B. bassiana may be able to alleviate oxidative stress by enhancing lipid catabolism and glycometabolism, thus decreasing membrane polarity and preventing polar H2O2 or ROS from permeating into fungal cells and protecting cells against oxidative injury. Meanwhile, most of the unsaturated fatty acids that are derived from glycerophospholipids hydrolysis can convert into oxylipins through autoxidation, which can prevent the reactive oxygen of H2O2 from attacking important macromolecules of the fungus. Results showed also that H2O2 treatment can enhance mycotoxins production which implies that oxidative stress may be able to increase the virulence of the fungus. In comparison to the control group, citric acid and UDP-N-acetylglucosamine were down-regulated, which suggested that metabolic flux was occurring to the TCA cycle and enhancing carbohydrate metabolism. The findings from this study will contribute to the understanding of how the molecular mechanisms of fungus respond to environmental and biological stress factors as well as how the manipulation of such metabolisms may lead to selection of more effective fungal strains for pest control., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Beauveria bassiana is a kind of world-wide entomopathogenic fungus and can also colonize plant rhizosphere. Previous researches showed differential expression of genes when entomopathogenic fungi are cultured in insect or plant materials. However, so far there is no report on metabolic alterations of B. bassiana in the environments of insect or plant. The purpose of this paper is to address this problem. Herein, we first provide the metabolomic analysis of B. bassiana cultured in insect pupae extracts (derived from Euproctis pseudoconspersa and Bombyx mori, EPP and BMP), plant root exudates (derived from asparagus and carrot, ARE and CRE), distilled water and minimal media (MM), respectively. Principal components analysis (PCA) shows that mycelia cultured in pupae extracts and root exudates are evidently separated and individually separated from MM, which indicates that fungus accommodates to insect and plant environments by different metabolic regulation mechanisms. Subsequently, orthogonal projection on latent structure-discriminant analysis (OPLS-DA) identifies differential metabolites in fungus under three environments relative to MM. Hierarchical clustering analysis (HCA) is performed to cluster compounds based on biochemical relationships, showing that sphingolipids are increased in BMP but are decreased in EPP. This observation further implies that sphingolipid metabolism may be involved in the adaptation of fungus to different hosts. In the meantime, sphingolipids are significantly decreased in root exudates but they are not decreased in distilled water, suggesting that some components of the root exudates can suppress sphingolipid to down-regulate sphingolipid metabolism. Pathway analysis finds that fatty acid metabolism is maintained at high level but non-ribosomal peptides (NRP) synthesis is unaffected in mycelia cultured in pupae extracts. In contrast, fatty acid metabolism is not changed but NRP synthesis is high in mycelia cultured in root exudates and distilled water. This indicates that fungal fatty acid metabolism is enhanced when contacting insect, but when in the absence of insect hosts NRP synthesis is increased. Ornithine, arginine and GABA are decreased in mycelia cultured in pupae extracts and root exudates but remain unchanged in distilled water, which suggests that they may be associated with fungal cross-talk with insects and plants. Trehalose and mannitol are decreased while adenine is increased in three conditions, signifying carbon shortage in cells. Together, these results unveil that B. bassiana has differential metabolic responses in pupae extracts and root exudates, and metabolic similarity in root exudates and distilled water is possibly due to the lack of insect components., (Copyright © 2015. Published by Elsevier Inc.)

The fungal pathogen Beauveria bassiana causes serious economic losses in sericulture. Its origin is usually attributed to the release of B. bassiana insecticides against pine caterpillars (Dendrolimus punctuatus). In the present study, 488 B. bassiana isolates obtained from silkworm (Bombyx mori) collected from 13 Chinese provinces, and 327 B. bassiana isolates obtained from D. punctatus collected from 9 provinces, were analyzed for population genetic structure using the ISSR technique based on genetic distance. A UPGMA dendrogram clustered them into three independent clades: two B. mori clades and one D. punctatus clade. A 3-D principal component analysis further divided them into two completely independent host groups, revealing high host-specificity. This suggested that white muscardine occurring in B. mori populations throughout southern China was not caused by any B. bassiana strain either naturally prevailing in D. punctatus populations or by any strain artificially released as a fungal insecticide against D. punctatus. We further investigated the genetic differentiation coefficient Gst and gene flow between B. mori-pathogenic and D. punctatus-pathogenic B. bassiana isolates from across China and from five provinces inhabited by both B. mori and D. punctatus. The Gst value across China was computed as 0.410, while the values of the five provinces ranged from 0.508 to 0.689; all above 0.25, which is the threshold for significant genetic differentiation. This suggests that B. bassiana strains isolated from the two different hosts maintained their respective heredity without a convergent homogenization trend, and reduces the possibility that the host range of the caterpillar isolates could expand and enhance their virulence in B. mori. These findings indicate that the use of B. bassiana does not threaten the safety of sericulture., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Ophiocordycipitaceae is a diverse family comprising ecologically, economically, medicinally, and culturally important fungi. The family was recognized due to the polyphyly of the genus Cordyceps and the broad diversity of the mostly arthropod-pathogenic lineages of Hypocreales. The other two cordyceps-like families, Cordycipitaceae and Clavicipitaceae, will be revised taxonomically elsewhere. Historically, many species were placed in Cordyceps, but other genera have been described in this family as well, including several based on anamorphic features. Currently there are 24 generic names in use across both asexual and sexual life stages for species of Ophiocordycipitaceae. To reflect changes in Art. 59 in the International Code of Nomenclature for algae, fungi, and plants (ICN), we propose to protect and to suppress names within Ophiocordycipitaceae, and to present taxonomic revisions in the genus Tolypocladium, based on rigorous and extensively sampled molecular phylogenetic analyses. When approaching this task, we considered the principles of priority, monophyly, minimizing taxonomic revisions, and the practical utility of these fungi within the wider biological research community.

Based on the internal transcribed spacer and inter-simple sequence repeats (ISSR), the phylogenetic relationship and genetic diversity of Metarhizium spp., pathogens found in Chinese burrower bugs, Schiodtella formosana, were analyzed. The results showed that the causative agents of the epizootic green muscardine disease in populations of S. formosana were actually composed of M. anisopliae and its sister species, M. robertsii. The genetic structure of Metarhizium spp. populations were assessed using ten ISSR. A 3D principal component analysis of 51 isolates sampled on different occasions revealed that the Metarhizium spp. populations were temporally heterogeneous. They differentiated into two main clades including over 71 % of all strains causing epizootics, with a similarity of 83 %. The population differentiation was relatively low (G ( ST ), 0.2080), reflecting a large proportion of gene differentiation (79.2 %) within the populations. Further knowledge of the complex species and heterogeneous populations of Metarhizium spp. may be necessary for sustainable control methods of S. formosana.

A panzootic in praying mantid species Tenodera sinensis and Statilia maculate, caused by Beauveria bassiana, occurred in north, southwest and southeast regions of Anhui Province, eastern China in Autumn, 2009. A 3-d principal component analysis (PCA) of 123 isolates from three sites revealed that the B. bassiana populations were heterogeneous with obvious dominance. Furthermore, the causal source of the panzootic in Anhui was shown to be polyphyletic. The populations were homogenized into homogenous subunits for investigation of genetic structure by inter-simple sequence repeat (ISSR) markers. Variance was greater than 70%, largely due to genetic differences within populations and subpopulations. Genetic distances and genetic differentiation were negatively associated with geographic distances and it was speculated that this was due to the effects of monsoons and topography. Mantid isolates were divided into five pathotypes based on a two-way cluster analysis of genetic distance. Pathotype I consisted of the predominant subpopulations of Huangcangyu and Chashui populations, with a genetic distance of 0.120 and gene flow up to 1.833. This pathotype caused a widespread epizootic in north and southwest Anhui, and Pathotype III caused enzootic at Site A in September and then epizootic in October, while the other three pathotypes caused enzootics at all three investigation sites. The widespread epizootics and isolated enzootics composed the polyphyletic panzootic in Anhui. A strong gene flow between isolates from the two mantid species was identified, resulting in negligible gene differentiation. This indicated a lack of host specificity in mantid isolates of B. bassiana., (Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.)

Objective: The aim was to identify the antitumor compounds of the fermentation broth of Paecilomyces militaris (strain RCEF0927)., Methods: Anti-tumor activity was tested with a resazurin cytotoxicity assay model with Chinese hamster ovary (CHO) cells. Bioactive compounds were analysed with combined method of High Performance Liquid Chromatography (HPLC), High Resolution Mass Spectrometer (HRMS) and antitumor assay., Results: Antitumor test showed that the fermentation broth had strong cytotoxicity against CHO cells. Extraction tests showed that ethylacetate was the best solvent for the bioactive constituents extracting. HPLC-DAD- HRMS-Cytotoxicity assay revealed that the molecular formula of the active compounds in the extract were possibly C10 H13 N5 O3, C22 H22 O9, C23 H24 O10, C22 H22 O10, C15 H10 O4, C15 H10O, C36 H70 O11, C36 H68 O12, C38 H74 O11, C40 H76 O13 and C44 H82 O14., Conclusion: The possible structures of the bioactive compounds were deduced with bioassay, HRMS, Uv and database inquiry as cordycepin, daizein, genistein 7,4'-dihydroxyisoflavone-7-O-(4"-O-methyl)-b-D-glucopyranoside, 7, 4'-dihydroxy-6- methoxyisoflavone-7-O-( 4"-O-methyl)-b-D-glucopyranoside, 5, 7, 4'-trihydroxy-isoflavone-7-O-(4"-O-methyl)-b-D-glucopyranoside, polyoxyethylene ether oleate, dehydro products of polyoxyethylene sorbitan monostearate, polyoxyethylene sorbitan monooleate, polyoxypropylene or polyoxybutene contained derivants of polyoxyethylene sorbitan fatty acid ester. Cytotoxicity of the compounds was revealed for the first time.

To improve the insecticidal efficacy of the entomopathogen Beauveria bassiana, the fungus was genetically modified with an insect-specific scorpion neurotoxin AAIT and an insect cuticle degrading protease PR1A from another insect pathogen (Metarhizium anisopliae). The wild-type and the transformants were bioassayed against the larvae of Masson's pine caterpillar Dendrolimus punctatus and the wax moth Galleria mellonella. In comparison to the wild-type strain, engineered isolates took fewer spores to kill 50% of pine caterpillars, 15-fold less for the aaIT single transformant Bb13T and eightfold less for the double transformant Bb13TPR1A, respectively. The median lethal times for Bb13T and Bb13TPR1A were reduced by 40% and 36.7%, respectively against D. punctatus and 24.4% and 20.9%, respectively against G. mellonella. Our data showed that the cotransformation of these two genes produced no synergistic effects on virulence improvement. It is evident from this study that AAIT could be degraded by the protease PR1A when they are expressed together, emphasizing that protein interactions need to be evaluated when working with multiple genes, particularly if they include proteases.

Objective: During a screening for free radical scavengers from metabolites of entomogenous fungi, we fond a fermentation broth of the strain RCEF 0881 of Hirsutella sp. exhibited strong radical scavenging activity. To make clear of the constituents of the active compounds, and prepare some pure active compound for further structure identification we launched this study., Methods: We used organic solvent for active compounds extraction. DPPH-TLC and DPPH- Microplate assay were used for activity analysis. Components analysis was carried out on a HPLC-DAD-HRMS, and bioactive compound preparation on a preparative RP-HPLC., Results: Our extraction tests showed that ethylacetate was the best solvent for the bioactive constituents extracting. HPLC-DAD-HRMS-DPPH assay revealed that the molecular formular of the radical scavengers existed in the extract were possibly C7H6O4, C8H8O3 and C12H14N2O. From the chromatographic and Uv properties, and the MS fragments, and database consulting, the compounds could be deduced as dihydroxybenzoic acid, methyl-hydroxyl benzoic acid, and an alkaloid, however, the structures are still needed to be confirmed. The pick area of HPLC and MS showed that the compound C12H14N2O was the main component of the extract. It was isolated via activity directed fractionation. The activity of the prepared compound was confirmed with DPPH-TLC assay and its purity was confirmed with HPLC-DAD-HR-ESIMS. The occurance of the three active compounds in entomogenous fungi was revealed for the first time.