Species classified in Cordycipitaceae ( Hypocreales ) include multiple entomopathogenic fungi. Numerous changes have recently occurred in the nomenclature of cordycipitaceous fungi due to the single ...naming system proposed for pleomorphic fungi in 2011. Species of Cordycipitaceae are widely applied as herbal medicines, especially in Asian cultures. However, the diversity of Cordycipitaceae in Taiwan is based on relatively few literature records. Here we conducted a comprehensive survey of this family throughout the island of Taiwan and provided a glimpse of the diversity and distribution patterns. In addition, the present study reassesses the generic and species boundaries of Cordycipitaceae and finally provides an updated phylogenetic overview of Cordyceps and allied genera. Phylogenetic reconstructions using combined ITS, nrLSU, tef1-α , rpb1 , and rpb2 sequence data, along with morphological features, resulted in 10 novel species: Akanthomyces taiwanicus sp. nov. , Blackwellomyces taiwanensis sp. nov. , Cordyceps hehuanensis sp. nov. , C. locastrae sp. nov. , C. malleiformis sp. nov. , C. pseudorosea sp. nov. , C. siangyangensis sp. nov. , Samsoniella lasiocampidarum sp. nov. , S. yuanzuiensis sp. nov. , and Simplicillium salviniae sp. nov. ; and nine new records for Taiwan: A. kanyawimiae , A. muscarius , S. cardinalis , S. hepiali , B. lii , B. medogensis , C. lepidopterorum , C. neopruinosa , and Si. chinense . Furthermore, we provided DNA sequence data of the ex-type strains of C. ninchukispora for the first time and determined the species limits of the taxon. In addition, the present study proposed to synonymize B. staphylinidicola and C. jakajanicola under B. bassiana and C. lepidopterorum , respectively. Moreover, three species, C. roseostromata , C. kyushuensis , and C. shuifuensis , that clustered within the species clade of C. militaris are proposed to be synonymized under the latter taxon. To maintain the monophyly of Cordyceps , we propose to classify Parahevansia koratensis in Cordyceps , which makes the genus Parahevansia obsolete.
Infections mediated by broad host range entomopathogenic fungi represent seminal observations that led to one of the first germ theories of disease and are a classic example of a co-evolutionary arms ...race between a pathogen and target hosts. These fungi are able to parasitize susceptible hosts via direct penetration of the cuticle with the initial and potentially determining interaction occurring between the fungal spore and the insect epicuticle. Entomogenous fungi have evolved mechanisms for adhesion and recognition of host surface cues that help direct an adaptive response that includes the production of: (a) hydrolytic, assimilatory, and/or detoxifying enzymes including lipase/esterases, catalases, cytochrome P450s, proteases, and chitinases; (b) specialized infectious structures, e.g., appressoria or penetrant tubes; and (c) secondary and other metabolites that facilitate infection. Aside from immune responses, insects have evolved a number of mechanisms to keep pathogens at bay that include: (a) the production of (epi) cuticular antimicrobial lipids, proteins, and metabolites; (b) shedding of the cuticle during development; and (c) behavioral-environmental adaptations such as induced fever, burrowing, and grooming, as well as potentially enlisting the help of other microbes, all intended to stop the pathogen before it can breach the cuticle. Virulence and host-defense can be considered to be under constant reciprocal selective pressure, and the action on the surface likely contributes to phenomena such as strain variation, host range, and the increased virulence often noted once a (low) virulent strain is "passaged" through an insect host. Since the cuticle represents the first point of contact and barrier between the fungus and the insect, the "action on the surface" may represent the defining interactions that ultimately can lead either to successful mycosis by the pathogen or successful defense by the host. Knowledge concerning the molecular mechanisms underlying this interaction can shed light on the ecology and evolution of virulence and can be used for rational design strategies at increasing the effectiveness of entomopathogenic fungi for pest control in field applications.
Previous research on the identification of fungi by means of their Raman spectra (i.e. spectra based on the inelastic scattering of light) of their spores indicates that this approach could be a ...fast, cheap and reliable method to distinguish fungi. Entomopathogenic fungi are used in commercially available insecticides (mycoinsecticides), in particular species of the genera Beauveria and Metarhizium. The identification of fungi in infected organisms is necessary for efficacy studies as well as in environmental impact assessments. This study aims at developing a method to differentiate isolates of these fungi, more precisely isolates of Metarhizium brunneum (Ca8II, Cb15III, Cb16III), Metarhizium pemphigi (X1c) and Beauveria bassiana (DSM 62075) as a non-related reference. To this end, fungi were grown on different culture media (both artificial and natural); samples were taken at different ages of the culture to assess possible impacts of nutrition and age on conidial pigmentation. It was possible to obtain spectra from the conidia of these fungi. The final predictive model was capable of determining isolated conidia grown on model insects with an overall goodness of prediction of 98.8% without any further sample preparation. In conclusion, Raman microspectroscopy proves to be a reliable and fast approach to distinguish entomopathogenic fungi.
Entomopathogenic fungi (EPF) are the microorganisms thatspecifically infect and often kill insects and other arthropods. EPF is themost effective biocontrol agent against insects in the natural ...ecosystem whichcould be an effective alternative to chemical insecticides in bio-intensivepest management. Beauveria bassiana, one of the most prevalentsoil-borne entomopathogens, has virulence on insect pests. The present study isaimed to evaluate the pathogenicity of a native isolate of the entomopathogenicfungus B. bassiana isolated from the soil samples of a cotton field(Kuthukkal) in the Tirunelveli district of Tamil Nadu against Dysdercuscingulatus. Bio-efficacy trials were carried out with six differentconcentrations viz., 4.6 × 103,1.5× 104, 5.0 × 105, 2.7 × 106, 3.2 × 107,and 2.8 x 108 (spores/mL) in all the five nymphal instars and theadults of D. cingulatus. A 100% mortality was observed in higherconcentrations 2.8 x 108 (spores/mL) at 120hrs after treatment. The resultsof the present study show that the isolate seems to be highly promising in thepest management of D. cingulatus.
The objectives of this study were to quantify the virulence of four entomopathogenic fungal species to pupae of Rhagoletis pomonella (Walsh) (Diptera: Tephritidae) and to determine the potential to ...combine entomopathogenic fungi (EPFs) and entomopathogenic nematodes (EPNs) for biological control of this pest. The four species of EPFs included Beauveria bassiana (strain GHA), Metarhizium brunneum (strain F52), Isaria javanica (wf GA17), and Isaria fumosorosea (Apopka 97 strain). In laboratory assays, all fungi reduced adult emergence but there were no differences between fungal species. Isaria javanica and M. brunneum were examined further in a EPFs and EPNs bioassay that also included the EPNs Steinernema carpocapsae (ALL strain) and S. riobrave (355 strain). All nematodes and fungi were applied either alone or in combination (fungus + nematode). There were no differences between species within the same entomopathogen group (fungi and nematodes). However, the treatment with S. riobrave resulted in lower R. pomonella emergence than either fungal species. The combination of S. riobrave and I. javanica resulted in the lowest R. pomonella emergence (3%) at fourth-week interval, which was significantly lower than any of the single-agent applications, yet virulence of the other three combination treatments was not different from their respective nematode treatments applied alone. Additive interactions were detected for all fungus–nematode combinations. This study suggests that application of entomopathogenic nematodes and fungi could be an effective option to suppress R. pomonella populations.
Fungal entomopathogens have been proposed as environmentally friendly alternatives to chemical control. Unfortunately, their effectiveness continues to be limited by their susceptibility to ...ultraviolet (UV) light and low moisture. A relatively recent development, the use of fungal entomopathogens as endophytes, might overcome the traditional obstacles impeding the widespread adoption of fungal entomopathogens and also provide a novel alternative for management of insect pests and plant pathogens. In addition, some fungal entomopathogens could also function as biofertilizers. Eighty-five papers covering 109 individual fungal entomopathogen studies involving 12 species in six genera are reviewed. Thirty-eight plant species in 19 families were studied, with maize, common bean, and tomato being the most investigated. Of the 85 papers, 39 (46%) examined the effects of fungal entomopathogen endophytism on 33 insect species in 17 families and eight orders. Thirty-four (40%) examined plant response to endophytism, corresponding to 20 plant species. Various inoculation techniques (e.g., foliar sprays, soil drenching, seed soaking, injections, etc.) are effective in introducing fungal entomopathogens as endophytes, but colonization appears to be localized and ephemeral. The field of insect pathology will not substantially profit from dozens of additional studies attempting to introduce fungal entomopathogens into a wider array of plants, without attempting to understand the mechanisms underlying endophytism, the responses of the plant to such endophytism, and the consequent responses of insect pests and plant pathogens. This review presents several areas that should receive focused attention to increase the probability of success for making this technology an effective alternative to chemical control.
Four new species of the genus Niveomyces are described from Thailand. They were found as mycoparasites on: Ophiocordyceps infecting flies (Diptera) for Niveomyces albus; ants (Hymenoptera) for N. ...formicidarum; and leafhoppers (Hemiptera)
for N. hirsutellae and N. multisynnematus. A new genus, Pseudoniveomyces with two species: Pseudoniveo. blattae (type species), parasitic on Ophiocordyceps infecting cockroaches, and Pseudoniveo. arachnovorum, found on a spider egg sac, are also described.
These fungi share a common feature which is a sporothrix-like asexual morph. Based on our molecular data, Sporothrix insectorum is shown to be affiliated to the genus Niveomyces, and thus a new combination N. insectorum comb. nov. is proposed. Niveomyces coronatus,
N. formicidarum and N. insectorum formed the N. coronatus species complex found on ant-pathogenic Ophiocordyceps from different continents. Pseudoniveomyces species are distinguished from Niveomyces spp. based on the presence of fusoid macroconidia in
culture and a red pigment diffused in the medium, resembling to Gibellula and Hevansia. The molecular phylogenetic analyses also confirmed its generic status. The host/substrates associated with the genera within Cordycipitaceae were mapped onto the phylogeny to demonstrate
that mycoparasitism also evolved independently multiple times in this family.
The incorporation of entomopathogenic fungi as biocontrol agents into Integrated Pest Management (IPM) programs without doubt, has been highly effective. The ability of these fungal pathogens such as
...and
to exist as endophytes in plants and protect their colonized host plants against the primary herbivore pests has widely been reported. Aside this sole role of pest management that has been traditionally ascribed to fungal endophytes, recent findings provided evidence of other possible functions as plant yield promoter, soil nutrient distributor, abiotic stress and drought tolerance enhancer in plants. However, reports on these additional important effects of fungal endophytes on the colonized plants remain scanty. In this review, we discussed the various beneficial effects of endophytic fungi on the host plants and their primary herbivore pests; as well as some negative effects that are relatively unknown. We also highlighted the prospects of our findings in further increasing the acceptance of fungal endophytes as an integral part of pest management programs for optimized crop production.
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