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1.
J Invertebr Pathol ; 186: 107673, 2021 11.
Article in English | MEDLINE | ID: mdl-34626615

ABSTRACT

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.


Subject(s)
Diptera/microbiology , Entomophthorales/classification , Animals , Entomophthorales/genetics , Entomophthorales/physiology , Genotype , Spores, Fungal/cytology
2.
J Invertebr Pathol ; 175: 107444, 2020 09.
Article in English | MEDLINE | ID: mdl-32707095

ABSTRACT

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.


Subject(s)
Entomophthorales/classification , Insect Control , Muscidae/microbiology , Pest Control, Biological , Animals , Entomophthorales/physiology , Female , Male
3.
Mycologia ; 112(6): 1060-1074, 2020.
Article in English | MEDLINE | ID: mdl-32412847

ABSTRACT

The fungal genus Massospora (Zoopagomycota: Entomophthorales) includes more than a dozen obligate, sexually transmissible pathogenic species that infect cicadas (Hemiptera) worldwide. At least two species are known to produce psychoactive compounds during infection, which has garnered considerable interest for this enigmatic genus. As with many Entomophthorales, the evolutionary relationships and host associations of Massospora spp. are not well understood. The acquisition of M. diceroproctae from Arizona, M. tettigatis from Chile, and M. platypediae from California and Colorado provided an opportunity to conduct molecular phylogenetic analyses and morphological studies to investigate whether these fungi represent a monophyletic group and delimit species boundaries. In a three-locus phylogenetic analysis including the D1-D2 domains of the nuclear 28S rRNA gene (28S), elongation factor 1 alpha-like (EFL), and beta-tubulin (BTUB), Massospora was resolved in a strongly supported monophyletic group containing four well-supported genealogically exclusive lineages, based on two of three methods of phylogenetic inference. There was incongruence among the single-gene trees: two methods of phylogenetic inference recovered trees with either the same topology as the three-gene concatenated tree (EFL) or a basal polytomy (28S, BTUB). Massospora levispora and M. platypediae isolates formed a single lineage in all analyses and are synonymized here as M. levispora. Massospora diceroproctae was sister to M. cicadina in all three single-gene trees and on an extremely long branch relative to the other Massospora, and even the outgroup taxa, which may reflect an accelerated rate of molecular evolution and/or incomplete taxon sampling. The results of the morphological study presented here indicate that spore measurements may not be phylogenetically or diagnostically informative. Despite recent advances in understanding the ecology of Massospora, much about its host range and diversity remains unexplored. The emerging phylogenetic framework can provide a foundation for exploring coevolutionary relationships with cicada hosts and the evolution of behavior-altering compounds.


Subject(s)
Entomophthorales/genetics , Entomophthorales/pathogenicity , Evolution, Molecular , Hemiptera/microbiology , Animals , Entomophthorales/classification , Phylogeny , Psychotropic Drugs/metabolism , Zygomycosis/microbiology
4.
Med Mycol ; 58(2): 264-267, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31111900

ABSTRACT

Basidiobolus species were isolated from colonic biopsy samples of patients with gastrointestinal basidiobolomycosis (GIB) in southern Saudi Arabia. Isolated fungi were initially identified using classical mycological tools and confirmed by sequence analysis of the large subunit ribosomal RNA gene. Phenotypic tests revealed zygomycete-like fungi which conform to those of Basidiobolus species. Five sequenced strains formed a monophyletic clade in the 28S ribosomal RNA gene phylogenetic tree. They shared 99.97% similarity with B. haptosporus and 99.97% with B. haptosporus var. minor, and relatively lower similarity with B. ranarum (99.925%). The study suggests a new and a serious causal agent of GIB related to Basidiobolus haptosporus. These isolates are not related to B. ranarum, which is commonly linked to this disease.


Subject(s)
Colon/microbiology , Entomophthorales/classification , Phylogeny , Zygomycosis/microbiology , Biopsy , Colon/pathology , Entomophthorales/genetics , Entomophthorales/pathogenicity , Gastrointestinal Diseases/microbiology , Humans , RNA, Ribosomal, 28S/genetics , Saudi Arabia , Zygomycosis/diagnosis
5.
G3 (Bethesda) ; 8(10): 3311-3319, 2018 10 03.
Article in English | MEDLINE | ID: mdl-30111619

ABSTRACT

Insect-pathogenic fungi use subtilisin-like serine proteases (SLSPs) to degrade chitin-associated proteins in the insect procuticle. Most insect-pathogenic fungi in the order Hypocreales (Ascomycota) are generalist species with a broad host-range, and most species possess a high number of SLSPs. The other major clade of insect-pathogenic fungi is part of the subphylum Entomophthoromycotina (Zoopagomycota, formerly Zygomycota) which consists of high host-specificity insect-pathogenic fungi that naturally only infect a single or very few host species. The extent to which insect-pathogenic fungi in the order Entomophthorales rely on SLSPs is unknown. Here we take advantage of recently available transcriptomic and genomic datasets from four genera within Entomophthoromycotina: the saprobic or opportunistic pathogens Basidiobolus meristosporus, Conidiobolus coronatus, C. thromboides, C. incongruus, and the host-specific insect pathogens Entomophthora muscae and Pandora formicae, specific pathogens of house flies (Muscae domestica) and wood ants (Formica polyctena), respectively. In total 154 SLSP from six fungi in the subphylum Entomophthoromycotina were identified: E. muscae (n = 22), P. formicae (n = 6), B. meristosporus (n = 60), C. thromboides (n = 18), C. coronatus (n = 36), and C. incongruus (n = 12). A unique group of 11 SLSPs was discovered in the genomes of the obligate biotrophic fungi E. muscae, P. formicae and the saprobic human pathogen C. incongruus that loosely resembles bacillopeptidase F-like SLSPs. Phylogenetics and protein domain analysis show this class represents a unique group of SLSPs so far only observed among Bacteria, Oomycetes and early diverging fungi such as Cryptomycota, Microsporidia, and Entomophthoromycotina. This group of SLSPs is missing in the sister fungal lineages of Kickxellomycotina and the fungal phyla Mucoromyocta, Ascomycota and Basidiomycota fungi suggesting interesting gene loss patterns.


Subject(s)
Entomophthorales/classification , Entomophthorales/genetics , Insecta/microbiology , Subtilisins/genetics , Amino Acid Motifs , Amino Acid Sequence , Animals , Catalytic Domain , Cluster Analysis , Databases, Nucleic Acid , Entomophthorales/enzymology , Phylogeny , Position-Specific Scoring Matrices , Protein Domains , Sequence Analysis, DNA , Subtilisins/chemistry , Subtilisins/metabolism
6.
Microbiol Spectr ; 5(3)2017 06.
Article in English | MEDLINE | ID: mdl-28597822

ABSTRACT

Fungi must meet four criteria to infect humans: growth at human body temperatures, circumvention or penetration of surface barriers, lysis and absorption of tissue, and resistance to immune defenses, including elevated body temperatures. Morphogenesis between small round, detachable cells and long, connected cells is the mechanism by which fungi solve problems of locomotion around or through host barriers. Secretion of lytic enzymes, and uptake systems for the released nutrients, are necessary if a fungus is to nutritionally utilize human tissue. Last, the potent human immune system evolved in the interaction with potential fungal pathogens, so few fungi meet all four conditions for a healthy human host. Paradoxically, the advances of modern medicine have made millions of people newly susceptible to fungal infections by disrupting immune defenses. This article explores how different members of four fungal phyla use different strategies to fulfill the four criteria to infect humans: the Entomophthorales, the Mucorales, the Ascomycota, and the Basidiomycota. Unique traits confer human pathogenic potential on various important members of these phyla: pathogenic Onygenales comprising thermal dimorphs such as Histoplasma and Coccidioides; the Cryptococcus spp. that infect immunocompromised as well as healthy humans; and important pathogens of immunocompromised patients-Candida, Pneumocystis, and Aspergillus spp. Also discussed are agents of neglected tropical diseases important in global health such as mycetoma and paracoccidiomycosis and common pathogens rarely implicated in serious illness such as dermatophytes. Commensalism is considered, as well as parasitism, in shaping genomes and physiological systems of hosts and fungi during evolution.


Subject(s)
Fungi/classification , Fungi/pathogenicity , Host-Pathogen Interactions/physiology , Mycoses/microbiology , Ascomycota/classification , Ascomycota/pathogenicity , Basidiomycota/classification , Basidiomycota/pathogenicity , Biological Evolution , Body Temperature , Entomophthorales/classification , Entomophthorales/pathogenicity , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate/immunology , Immunocompromised Host , Mucorales/classification , Mucorales/pathogenicity , Mycetoma/microbiology , Mycoses/immunology , Opportunistic Infections/microbiology , Phylogeny , Virulence
7.
Rev. argent. microbiol ; 46(1): 49-52, mar. 2014.
Article in English | LILACS | ID: biblio-1009809

ABSTRACT

Se encontraron cuatro especies de hongos Entomophthorales, Pandora neoaphidis, Zoophthora radicans, Entomophthora planchoniana (Entomophthorales: Entomophthoraceae) y Neozygites fresenii (Neozygitales: Neozygitaceae) infectando a Aphis craccivora, Therioaphis trifolii, Acyrthosiphon pisum y a especies no identificadas pertenecientes al género Acyrthosiphon en cultivos de alfalfa (Medicago sativa L.), en la Argentina. Los muestreos fueron realizados en cinco sitios (Ceres, Rafaela, Sarmiento, Monte Vera y Bernardo de Irigoyen) de la provincia de Santa Fe. Zoophthora radicans fue el patógeno más importante registrado principalmente en Acyrthosiphon sp. Zoophthora radicans fue exitosamente aislado y mantenido en cultivos puros. Este estudio documenta por primera vez en la Argentina la presencia de hongos Entomophthorales infectando áfidos en alfalfa


Four species of entomophthoroid fungi, Pandora neoaphidis (Entomophthorales: Entomophthoraceae), Zoophthora radicans (Entomophthorales: Entomophthoraceae), Entomophthora planchoniana (Entomophthorales: Entomophthoraceae) and Neozygites fresenii (Neozygitales: Neozygitaceae) were found to infect Aphis craccivora, Therioaphis trifolii, and Acyrthosiphon pisum and unidentified species of Acyrthosiphon on lucerne in Argentina. Samples were collected from five sites (Ceres, Rafaela, Sarmiento, Monte Vera and Bernardo de Irigoyen) in the province of Santa Fe. In this study, Zoophthora radicans was the most important pathogen and was recorded mainly on Acyrthosiphon sp. Zoophthora radicans was successfully isolated and maintained in pure cultures. This study is the first report of entomophthoroid fungi infecting lucerne (Medicago sativa L.) aphids in Argentina


Subject(s)
Aphids/pathogenicity , Argentina/epidemiology , Medicago sativa/toxicity , Entomophthorales/isolation & purification , Entomophthorales/classification
8.
Mycologia ; 105(3): 661-9, 2013.
Article in English | MEDLINE | ID: mdl-23233508

ABSTRACT

An entomophthoralean fungus causing epizootics in populations of the cypress aphid, Cinara cupressi Buckton, in Chile is described as a new species, Neozygites osornensis Montalva et Barta. The aphid pathogen is described based on morphological characters. An exhaustive description, illustrations and a comparison with closely related species are provided. The fungus differs from similar Neozygites species by smaller hyphal bodies, nuclei, primary conidia, capilliconidia and capilliphores and by noticeably different shape of capilliconidia. A key to aphid-pathogenic species of Neozygites is also included.


Subject(s)
Aphids/microbiology , Entomophthorales/classification , Entomophthorales/isolation & purification , Animals , Chile , Cupressus , Entomophthorales/ultrastructure
9.
Fungal Biol ; 116(2): 196-203, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22289765

ABSTRACT

The entomopathogenic fungus Pandora neoaphidis is a recognized pathogen of aphids, causes natural epizootics in aphid populations, and interacts and competes with aphid predators and parasitoids. Survival of entomophthoralean fungi in periods of unsuitable weather conditions or lack of appropriate host insects is accomplished mainly by thick-walled resting spores (zygospores or azygospores). However, resting spores are not known for some entomophthoralean species such as P. neoaphidis. Several hypotheses of P. neoaphidis winter survival can be found in the literature but so far these hypotheses do not include the presence of resting spores. Resting spores were found in an aphid population where P. neoaphidis was the only entomophthoralean fungus observed during surveys conducted in organic horticultural crops in greenhouses and open fields in Buenos Aires province, Argentina. This study sought to use molecular methods to confirm that these resting spores were, in fact, those of P. neoaphidis while further documenting and characterizing these resting spores that were produced in vivo in aphid hosts. The double-walled resting spores were characterized using light and transmission electron microscopy. The Argentinean resting spores clustered together with P. neoaphidis isolates with bootstrap values above 98 % in the small subunit ribosomal RNA (SSU rRNA) sequence analysis and with bootstrap values above 99 % the Internal Transcribed Spacer (ITS) II region sequence analysis. This study is the first gene-based confirmation from either infected hosts or cultures that P. neoaphidis is able to produce resting spores.


Subject(s)
Aphids/microbiology , Entomophthorales/cytology , Entomophthorales/growth & development , Spores, Fungal/cytology , Spores, Fungal/growth & development , Animals , Argentina , Cluster Analysis , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Entomophthorales/classification , Entomophthorales/genetics , Genes, rRNA , Microscopy , Molecular Sequence Data , Phylogeny , RNA, Fungal/genetics , RNA, Ribosomal, 18S/genetics , Sequence Analysis, DNA , Spores, Fungal/classification , Spores, Fungal/genetics
10.
Fungal Biol ; 116(1): 90-7, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22208604

ABSTRACT

Two species of mites inhabiting a pine forest soil were screened for associated fungi. The fungal community composition was assessed in 49 mite and 19 soil samples by environmental PCR with a focus on fungi of the genus Basidiobolus. PCR products of the fungal ITS rRNA gene were analyzed by sub-cloning, RFLP-analysis, and sequencing. Thereby Basidiobolus haptosporus was found for the first time to be frequently associated with the gamasid mite species Leptogamasus obesus, while being absent from the oribatid mite Oppiella subpectinata, and from the surrounding soil. The fungus was isolated in pure culture for a detailed morphological characterization and experimental approaches concerning the nature of this fungus-mite association. The experiments and a supporting microscopic screening of freshly captured gamasid mites revealed no indications for the fungus being localized in the mites' gut or haemocoel, but a single spore was found attached to an individual of L. obesus. However, an exclusive phoretic association does not satisfactorily explain the frequent detection of B. haptosporus DNA on or in L. obesus, and the absence of the fungus from soil samples seems not to be in line with its assumed ecology as a widespread saprobic soil fungus. Therefore, a second host species in the life cycle of B. haptosporus is discussed as a working hypothesis.


Subject(s)
Acari/microbiology , Entomophthorales/isolation & purification , Animals , Biota , Cloning, Molecular , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Entomophthorales/classification , Entomophthorales/genetics , Molecular Sequence Data , Molecular Typing , Mycological Typing Techniques , Phylogeny , Polymerase Chain Reaction , Sequence Analysis, DNA , Soil Microbiology
11.
Clin Infect Dis ; 54 Suppl 1: S8-S15, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22247451

ABSTRACT

Molecular phylogenetic analysis confirmed the phylum Zygomycota to be polyphyletic, and the taxa conventionally classified in Zygomycota are now distributed among the new phylum Glomeromycota and 4 subphyla incertae sedis (uncertain placement). Because the nomenclature of the disease zygomycosis was based on the phylum Zygomycota (Zygomycetes) in which the etiologic agents had been classified, the new classification profoundly affects the name of the disease. Zygomycosis was originally described as a convenient and inclusive name for 2 clinicopathologically different diseases, mucormycosis caused by members of Mucorales and entomophthoramycosis caused by species in the order Entomophthorales of Zygomycota. Without revision of original definition, the name "zygomycosis," however, has more often been used as a synonym only for mucormycosis. This article reviews the progress and changes in taxonomy and nomenclature of Zygomycota and the disease zygomycosis. The article also reiterates the reasons why the classic names "mucormycosis" and "entomophthoramycosis" are more appropriate than "zygomycosis."


Subject(s)
Entomophthorales/classification , Mucorales/classification , Mucormycosis/classification , Zygomycosis/classification , DNA, Ribosomal/genetics , Entomophthorales/genetics , Entomophthorales/pathogenicity , Entomophthorales/physiology , Evolution, Molecular , Genes, Fungal , Humans , Mucorales/genetics , Mucorales/pathogenicity , Mucorales/physiology , Mucormycosis/microbiology , Mucormycosis/pathology , Phylogeny , RNA, Ribosomal/genetics , Ribosome Subunits, Small/genetics , Species Specificity , Spores, Fungal/physiology , Zygomycosis/microbiology , Zygomycosis/pathology
12.
Fungal Biol ; 115(6): 485-92, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21640313

ABSTRACT

To date, among the zygomycete fungi that have been examined, a Spitzenkörper has not been reported. In this paper, the cytoplasmic order of hyphal tip cells of Basidiobolus sp., a zygomycete genus of uncertain phylogeny, has been examined using light microscopy and transmission electron microscopy methods. With phase-contrast light optics, a phase-dark body was observed at the tips of growing hyphae of Basidiobolus sp. The hyphal apex also showed high affinity for FM4-64 labelling resulting in an intense fluorescence signal. The phase-dark inclusion exhibited independent motility within the hyphal apex and its presence and position were correlated to the rate and direction of hyphal growth. The hyphal apex of Basidiobolus sp. did not contain γ-tubulin. Ultrastructural observations revealed a dense cluster of vesicles at the hyphal apex. These results suggest that the growing hypha of Basidiobolus sp. contains a Spitzenkörper, a character generally attributed to members of the ascomycete and basidiomycete fungi and not to zygomycete fungi.


Subject(s)
Entomophthorales/growth & development , Hyphae/growth & development , Entomophthorales/classification , Entomophthorales/cytology , Hyphae/classification , Hyphae/cytology , Phylogeny
13.
Fungal Biol ; 114(5-6): 498-506, 2010.
Article in English | MEDLINE | ID: mdl-20943161

ABSTRACT

Pandora neoaphidis (Entomophthoromycotina, Entomophthorales) is one of the most important fungal pathogens of aphids with great potential as a biological control agent. Development of tools that allow high-resolution monitoring of P. neoaphidis in the environment is a prerequisite for the successful implementation of biological control strategies. In this study, a single-nucleotide polymorphism (SNP) assay was developed. The assay targets 13 SNPs identified in 6 genomic regions including the largest subunit of nuclear RNA polymerase II (RPB1) gene, the second-largest subunit of nuclear RNA polymerase II (RPB2) gene, the ß-tubulin (BTUB) gene, the elongation factor 1α-like (EFL) gene, the large subunit (LSU) rRNA gene, and the small subunit (SSU) rRNA gene together with the internal transcribed spacer (ITS). The assay allowed the discrimination of 15 different SNP profiles among 19 P. neoaphidis isolates and 4 P. neoaphidis-infected cadavers. Results showed that the assay is applicable to DNA extracted from infected aphids allowing genotyping of the fungus without cultivation. The SNP assay provides an efficient tool for investigation of population structures and dynamics of P. neoaphidis, as well as its persistence and epidemiology in agro-ecosystems. Furthermore, it constitutes a powerful approach for monitoring potential biological control strains of P. neoaphidis in the environment.


Subject(s)
Entomophthorales/genetics , Entomophthorales/isolation & purification , Mycological Typing Techniques/methods , Polymorphism, Single Nucleotide , Animals , Base Sequence , DNA, Fungal/genetics , Entomophthorales/classification , Fungal Proteins/genetics , Genotype , Insecta/microbiology , Molecular Sequence Data , RNA Polymerase II/genetics
14.
J Invertebr Pathol ; 104(2): 157-9, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20230831

ABSTRACT

This study describes in vitro and in vivo azygospore production by nine isolates of Entomophaga maimaiga, a fungal pathogen of the gypsy moth, Lymantria dispar. The three E. maimaiga isolates that consistently produced azygospores in vitro were also strong producers of azygospores in vivo. However, two additional isolates that were strong azygospore producers in vivo did not produce azygospores in vitro. Isolates that produced azygospores in vitro produced both conidia and azygospores more frequently in vivo than isolates not producing azygospores in vitro. In vitro azygospore production varied over time as well as by isolate. After >2years of cold storage, while three isolates continued in vitro azygospore production, three isolates no longer produced azygospores in vitro.


Subject(s)
Entomophthorales/physiology , Moths/microbiology , Spores, Fungal/physiology , Animals , Entomophthorales/classification , Larva , Species Specificity , Spores, Fungal/classification
15.
Microbiology (Reading) ; 155(Pt 1): 174-185, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19118358

ABSTRACT

Zoophthora radicans is an entomopathogenic fungus with the potential to be used as an insect biological control agent. To better understand the mechanisms used by Z. radicans to infect different hosts, we generated expressed sequence tag (EST) datasets from a Z. radicans strain originally isolated from Pieris brassicae, and an isogenic strain passaged through Plutella xylostella. In total, 1839 ESTs were generated which clustered into 466 contigs and 433 singletons to provide a set of 899 unique sequences. Approximately 85 % of the ESTs were significantly similar (E< or =e(-03)) to other fungal genes, of which 69.6 % encoded proteins with a reported function. Proteins involved in protein synthesis and metabolism were encoded by 38.3 % of the ESTs, while 26.3 % encoded proteins involved in cell-cycle regulation, DNA synthesis, protein fate, transport, cell defence, transcription and RNA synthesis, and 4.9 % encoded proteins associated with cellular transport, signal transduction, control of cellular organization and cell-wall degradation. Several proteinases, including aspartic proteinases, trypsins, trypsin-like serine proteases and metalloproteases, with the potential to degrade insect cuticle were expressed by the two isolates.


Subject(s)
Entomophthorales/genetics , Entomophthorales/isolation & purification , Expressed Sequence Tags , Fungal Proteins/metabolism , Lepidoptera/microbiology , Animals , Biological Assay , Entomophthorales/classification , Entomophthorales/physiology , Fungal Proteins/genetics , Gene Expression Profiling , Gene Expression Regulation, Fungal , Gene Library , Host-Pathogen Interactions , Lepidoptera/classification , Lepidoptera/genetics , Sequence Analysis, DNA , Species Specificity , Virulence
16.
Exp Appl Acarol ; 46(1-4): 43-52, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18798001

ABSTRACT

A fungal pathogen provisionally identified as Neozygites cf. acaridis has recently been isolated from the Antarctic oribatid mite Alaskozetes antarcticus. The identification of the fungus is discussed with reference to recent changes in the taxonomy of Neozygites. The potential role of the fungus in the Antarctic mite populations is considered in relation to the known mite life cycles, and the particular environmental conditions in the Antarctic.


Subject(s)
Entomophthorales/isolation & purification , Host-Pathogen Interactions , Mites/microbiology , Animals , Antarctic Regions , Biodiversity , Cold Climate , Entomophthorales/classification , Entomophthorales/physiology
17.
Mycol Res ; 112(Pt 10): 1227-40, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18693001

ABSTRACT

Species-specific primers for Zoophthora radicans and Pandora bluckii were developed. To achieve this, partial sequences of DNA that encode for rRNA, more specifically, the ITS region (rDNA-ITS) were obtained from different isolates and analysed. Seven Z. radicans isolates (four from P. xylostella, and three from other lepidopteran hosts) and one P. blunckii isolate (from P. xylostella) were used. These isolates were selected based on PCR-RFLP patterns obtained from 22 isolates of P. blunckii and 39 isolates of Z. radicans. All P. blunckii isolates were from the same host (P. xylostella); 20 isolates were from Mexico, one from the Philippines, and one from Germany. The Z. radicans isolates were more diverse in geographical origin (Mexico, Kenya, Japan, New Zealand, Australia, Taiwan, Philippines, Malaysia, Uruguay, France, USA, Poland, Indonesia, Switzerland, Israel, China, and Denmark) and host origin (Lepidoptera, Hemiptera, Hymentoptera, and Diptera). Using conventional PCR, each pair of species-specific primers successfully detected each species of fungus from DNA extracted from infected host larvae either single- or dual-inoculated with both fungal species. The PCR-RFLP analysis also showed that Z. radicans was genetically more diverse than P. blunckii, although only a limited number of P. blunckii isolates from one country were considered. There was no direct relationship between genetic diversity and host or geographical origin. The relationship between genetic variation within both fungal species and host specificity or ecological adaptation is discussed.


Subject(s)
DNA Primers/genetics , Entomophthorales/isolation & purification , Moths/microbiology , Polymerase Chain Reaction/methods , Animals , DNA, Fungal/genetics , DNA, Ribosomal Spacer/genetics , Entomophthorales/classification , Entomophthorales/genetics , Genetic Variation , Larva/microbiology , Mexico , Molecular Sequence Data , Phylogeny , Polymorphism, Restriction Fragment Length , Species Specificity
18.
Rev. biol. trop ; 54(2): 311-315, jun. 2006. ilus, tab
Article in Spanish | LILACS | ID: lil-492067

ABSTRACT

Three species of Entomophthorales entomopathogenic fungi (Zygomycotina: Zygomycetes) have been identified from insects in agricultural crops (Buenos Aires Province, Argentina): Zoophthora radicans Batko (Brefeld); Entomophthora planchoniana Cornu and Pandora gammae (Weiser) Humber. Fungal structure measurements are reported.


Se informa de tres especies de hongos Entomophthorales en insectos encontrados en cultivos agrícolas en la Provincia de Buenos Aires, Argentina: Zoophthora radicans Batko (Brefeld); Entomophthora planchoniana Cornu y Pandora gammae (Weiser) Humber. Se incluyen las medidas de las estructuras fúngicas.


Subject(s)
Animals , Entomophthorales/pathogenicity , Insecta/microbiology , Host-Pathogen Interactions , Crops, Agricultural/microbiology , Zygomycosis/microbiology , Argentina , Population Density , Entomophthorales/classification , Entomophthorales/isolation & purification , Species Specificity
19.
Rev Biol Trop ; 54(2): 311-5, 2006 Jun.
Article in Spanish | MEDLINE | ID: mdl-18494301

ABSTRACT

Pathogenic fungi of insects from Argentina (Zygomycetes: Entomophthorales). Three species of Entomophthorales entomopathogenic fungi (Zygomycotina: Zygomycetes) have been identified from insects in agricultural crops (Buenos Aires Province, Argentina): Zoophthora radicans Batko (Brefeld); Entomophthora planchoniana Cornu and Pandora gammae (Weiser) Humber. Fungal structure measurements are reported.


Subject(s)
Crops, Agricultural/microbiology , Entomophthorales/pathogenicity , Host-Pathogen Interactions , Insecta/microbiology , Zygomycosis/microbiology , Animals , Argentina , Entomophthorales/classification , Entomophthorales/isolation & purification , Population Density , Species Specificity
20.
Mycol Res ; 109(Pt 8): 941-50, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16175797

ABSTRACT

Entomophaga maimaiga is a naturally occurring fungal pathogen specific to larvae of the gypsy moth, Lymantria dispar. E. maimaiga is thought to be native to Asia where its epizootics can suppress gypsy moth outbreaks. However, in the USA this beneficial fungal pathogen was not observed until 1989, although an isolate of E. maimaiga from Tokyo was released in Massachusetts to control gypsy moths as early as in 1910-1911, and another isolate from Ishikawa Prefecture in Japan was later released in 1985 and 1986 in New York and Virginia. Our objectives were to: (1) test the hypothesis that E. maimaiga populations in the USA have reduced genetic variability due to founder effects compared to the putative ancestral populations in Asia; (2) track the origin of the North American populations of this fungus; and (3) assess whether genetic differences among E. maimaiga isolates are correlated to morphological differences. We compared genetic diversity among 30 E. maimaiga isolates originating from seven states in the USA, five prefectures in Japan, one province of China and one region of far eastern Russia by AFLPs. Among 14 USA isolates, only ten polymorphic AFLP loci were found, whereas 56 polymorphic loci were found among 16 Asian isolates; 29 loci were polymorphic among 12 isolates from Japan alone. Average gene diversity (h) for the polymorphic loci was 0.223 +/- 0.005 for Asia (including Japan), 0.131 +/- 0.006 for Japan only, and 0.041 +/- 0.004 for the USA. Thus, native populations from Asia were more diverse than the USA populations. These results are consistent with the expectation of a population founded from a source population by a small number of individuals. Distance and parsimony analyses of AFLP data showed that the isolates from the USA formed one distinct clade that was most closely related to Japanese isolates collected outside the Tokyo area. No morphological variation of E. maimaiga from different geographical locations was detected.


Subject(s)
Entomophthorales/pathogenicity , Genetic Variation , Moths/microbiology , Animals , Asia , DNA, Fungal/analysis , Entomophthorales/classification , Entomophthorales/genetics , Entomophthorales/isolation & purification , Genetics, Population , Host-Parasite Interactions , Moths/immunology , North America , Phylogeny
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