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1.
Braz J Microbiol ; 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462595

RESUMO

Caves are unique environments characterized by spatial limitations, partial or total absence of direct light, and scarcity of organic carbon and nutrients. Caves are shelters for a variety of adapted animals and microorganisms such as fungi, many of which are still unknown. Amphichorda is a fungal genus belonging to the family Bionectriaceae, which includes cave-dwelling and entomopathogenic species with biotechnological applications. In this study, a new fungal species was identified using morphological and multi-locus phylogenetic analyses of the ITS, LSU, and TEF loci, in the Gruta Velha Nova limestone cave located in the Southern Espinhaço Range, Monjolos, Minas Gerais, Brazil. During the exposure of potato dextrose agar plates to the cave environment, an insect from the family Rhaphidophoridae passed by and fed on the culture medium, resulting in three fungal isolates. Phylogenetic analyses showed that these isolates formed a clade distinct from all known species, leading us to introduce a new species, Amphichorda monjolensis, which may be associated with this insect. Here, we also proposed two new combinations for species of acremonium-like fungi in the Bionectriaceae: Bulbithecium globosisporum (synonym: Acremonium globosisporum) and Hapsidospora curva (synonym: Acremonium curvum). The discovery of A. monjolensis highlights the potential of caves as shelters for new species with significant biotechnological importance.

2.
Braz J Microbiol ; 54(4): 3021-3031, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37880564

RESUMO

Caves are underground and natural environments mainly found in rocky terrain. Caves have a very specific microclimate, which benefits the occurrence of specific fungi. In recent studies, researchers have observed that caves harbour a great diversity of fungi. However, studies on fungal diversity in Brazilian caves are still incipient. In September 2019, airborne spore and soil samples were collected from the Monte Cristo cave, in the Southern Espinhaço Range, Diamantina, Minas Gerais state, Brazil. Two Cladosporium single-spore isolates, among other genera, were obtained from these samples. This study aimed to characterise these two fungal isolates based on their DNA sequence data and morphology. Phylogenetic analyses of the rDNA-ITS, ACT and TEF1-α loci revealed that the isolates belonged to the Cladosporium cladosporioides species complex. Both isolates did not cluster with any known species and were formally described and named herein as C. diamantinense and C. speluncae. This study presents taxonomic novelties and contributes to the knowledge about the fungal diversity in Brazilian caves.


Assuntos
Cladosporium , Brasil , Cladosporium/genética , Filogenia , DNA Ribossômico
3.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36690347

RESUMO

Lytic enzymes secreted by Kluyveromyces marxianus can lyse Saccharomyces cerevisiae cells. Their ability to hydrolyze yeast cell walls can be used in biotechnological applications, such as the production of glucans and protoplasts, as well as a biological control agent against plant pathogenic fungi. Herein, 27 proteins secreted by K. marxianus were identified by mass spectrometry analyses. Importantly, 14 out of the 27 proteins were classified as hydrolases. Indeed, the enzyme extract secreted by K. marxianus caused damage to S. cerevisiae cells and reduced yeast cell viability. Moreover, K marxianus inhibited spore germination and mycelial growth of the phytopathogenic fungus Botrytis cinerea in simultaneous cocultivation assays. We suggest that this inhibition may be partially related to the yeast's ability to secrete lytic enzymes. Consistent with the in vitro antagonistic tests, K. marxianus was able to protect strawberry fruits inoculated with B. cinerea. Therefore, these findings suggest that K. marxianus possesses potential as a biocontrol agent against strawberry gray mold during the postharvest stage and may also have potential against other phytopathogenic fungi by means of its lytic enzymatic arsenal.


Assuntos
Kluyveromyces , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Fungos , Kluyveromyces/metabolismo , Biotecnologia
4.
Braz J Microbiol ; 54(1): 349-360, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36598751

RESUMO

Several endophytic fungi have been reported to have produced bioactive metabolites. Some of them, including the Induratia species, have the capacity to emit volatile compounds with antimicrobial properties with broad spectrum against human and plant pathogens. The present study aimed to prospect the Induratia species producing volatile organic compounds (VOCs), in carqueja plants used in alternative medicine and coffee plants in Brazil. A total of 11 fungal isolates producing volatile metabolites were obtained by a parallel growth technique, using I. alba 620 as a reference strain. Phylogenetic relationships revealed the presence of at least three distinct species, I. coffeana, I. yucatanensis, and Induratia sp. SPME/GC/MS analyses of the VOCs in the headspace above the mycelium from Induratia species cultured for 10 days on PDA revealed the volatile profile emitted by I. coffeana CCF 572, I. coffeana COAD 2055, I. yucatanensis COAD 2062, and Induratia sp. COAD 2059. Volatile organic compounds produced by I. coffeana isolates presented antimicrobial activity against Aspergillus ochraceus, A. sclerotiorum, A. elegans, A. foetidus, A. flavus, A. tamari, A. tubingensis, A. sydowii, A. niger, A. caespitosus, A. versicolor, and A. expansum, sometimes by decreasing the growth rate or, mainly, by fully inhibiting colony growth. Fifty-eight percent of the target species died after 6 days of exposure to VOCs emitted by I. coffeana CCF 572. In addition, VOCs emitted by the same fungus inhibited the growth in A. ochraceus inoculated into coffee beans, which indicates that plants which have I. coffeana as an endophyte may be protected from attacks by this plant pathogen.


Assuntos
Anti-Infecciosos , Coffea , Compostos Orgânicos Voláteis , Xylariales , Humanos , Compostos Orgânicos Voláteis/metabolismo , Brasil , Filogenia , Anti-Infecciosos/metabolismo , Xylariales/metabolismo , Fungos
5.
J Microbiol Methods ; 187: 106272, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34166707

RESUMO

Although asterinaceous fungi have been studied for many years, all previous attempts to isolate, cultivate, and propagate these fungi in vitro have failed. This paper provides the first reports of in vitro isolation of representative strains of species belonging to five fungi from different genera belonging to Asterinales. To confirm if the sequences of DNA obtained from the mycelia are the same obtained in the direct extraction, a phylogenetic analysis of nuc LSU rDNA was performed. This paper reports for the first time the success of in vitro culturing of asterinaceous fungi using the ascospores ejection technique, opening perspectives of studies of genetics, physiology, among other aspects of the biology for this very understudied group of fungi.


Assuntos
Ascomicetos/crescimento & desenvolvimento , Ascomicetos/isolamento & purificação , Micologia/métodos , Ascomicetos/genética , Meios de Cultura , DNA Fúngico/química , DNA Fúngico/genética , DNA Fúngico/isolamento & purificação , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Ribossômico/isolamento & purificação , Micélio/crescimento & desenvolvimento , Filogenia , Folhas de Planta/microbiologia , Análise de Sequência de DNA , Esporos Fúngicos
6.
Braz. arch. biol. technol ; 63: e20180673, 2020. tab
Artigo em Inglês | LILACS | ID: biblio-1132156

RESUMO

Abstract Endophytic fungi belonging to the genus Muscodor now transferred to Induratia are known producers of bioactive volatile organic compounds (VOCs) with many industrial applications. However, the members of this genus have rarely been reported to produce non-volatile metabolites including enzyme. Enzymes of the endophytes are degraders of the polysaccharides available in the host plants and the knowledge of enzyme production by Induratia spp. may provide insights into their possible biotechnological applications. The aim of this study was to evaluate the activity of amylase, cellulase, lipase, pectinase, phytase, protease, endo β-1,4 glucanase and exo β-1,4 glucanase enzymes produced by fungi of the species Induratia coffeana, Induratia yucatanensis and Induratia sp. isolated from organic coffee plants. All Induratia spp. were able to produce the extracellular enzymes cellulase, pectinase, protease, and phytase. Eight fungi were able to produce lipase and four produced amylase. The specific activity of endo β-1, 4 glucanase and exo β-1,4 glucanase enzymes were detected for 9 and 8 endophytic fungi, respectively. This work demonstrated for the first time, the array of enzymes produced by Induratia spp. isolated from Coffea arabica in organic systems in Brazil.


Assuntos
Coffea/microbiologia , Ativação Enzimática , Compostos Orgânicos Voláteis/metabolismo , Endófitos/enzimologia , Brasil
7.
Biotechnol Biofuels ; 11: 226, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30151054

RESUMO

BACKGROUND: ß-Glucosidases are components of the cellulase system, a family of enzymes that hydrolyze the ß-1,4 linkages of cellulose. These proteins have been extensively studied due to the possibility of their use in various biotechnological processes. They have different affinities for substrates (depending on their source) and their activities can be used for saccharification of different types of biomass. In this context, the properties and the synergistic capacity of ß-glucosidases from different organisms, to supplement the available commercial cellulase cocktails, need a comprehensive evaluation. RESULTS: Two ß-glucosidases belonging to GH3 family were secreted by Penicillium citrinum UFV. PcßGlu1 (241 kDa) and PcßGlu2 (95 kDa) presented acidic and thermo-tolerant characteristics. PcßGlu1 showed Michaelis-Menten kinetics for all substrates tested with Km values ranging from 0.09 ± 0.01 (laminarin) to 1.7 ± 0.1 mM (cellobiose, C2) and kcat values ranging from 0.143 ± 0.005 (laminarin) to 8.0 ± 0.2 s-1 (laminaribiose, Lb). PcßGlu2 showed substrate inhibition for 4-methylumbelliferyl-ß-d-glucopyranoside (MUßGlu), p-nitrophenyl-ß-d-glucopyranoside (pNPßGlu), cellodextrins (C3, C4, and C5), N-octil-ß-d-glucopyranoside, and laminaribiose, with Km values ranging from 0.014 ± 0.001 (MUßGlu) to 0.64 ± 0.06 mM (C2) and kcat values ranging from 0.49 ± 0.01 (gentiobiose) to 1.5 ± 0.2 s-1 (C4). Inhibition constants (Ki) for PcßGlu2 substrate inhibition ranged from 0.69 ± 0.07 (MUßGlu) to 10 ± 1 mM (Lb). Glucose and cellobiose are competitive inhibitors of PcßGlu1 and PcßGlu2 when pNPßGlu is used as a substrate. For PcßGlu1 inhibition, Ki = 1.89 ± 0.08 mM (glucose) and Ki = 3.8 ± 0.1 mM (cellobiose); for PcßGlu2, Ki = 0.83 ± 0.05 mM (glucose) and Ki = 0.95 ± 0.07 mM (cellobiose). The enzymes were tested for saccharification of different biomasses, individually or supplementing a Trichoderma reesei commercial cellulose preparation. PcßGlu2 was able to hydrolyze banana pseudostem and coconut fiber with the same efficiency as the T. reesei cocktail, showing significant synergistic properties with T. reesei enzymes in the hydrolysis of these alternative biomasses. CONCLUSIONS: The ß-glucosidases from P. citrinum UFV1 present different enzymatic properties from each other and might have potential application in several biotechnological processes, such as hydrolysis of different types of biomass.

8.
Biosci. j. (Online) ; 33(2): 381-389, mar./apr. 2017. tab
Artigo em Inglês | LILACS | ID: biblio-966190

RESUMO

Endophytic fungi are a promising source for discovery of compounds with biotechnological potential. The aim of this study was to select and identify endophytic fungi from Coffea arabica that produce volatile organic compounds (VOCs), evaluate the effect of the VOCs produced by endophytic fungi on the growth of Rhizoctonia solani, Fusarium oxysporum, Phoma sp., Botrytis cinerea, Fusarium solani, Fusarium verticillioides, Cercospora coffeicola and Pestalotia longisetula, and select endophytic fungi with potential for biological control of Aspergillus ochraceus inoculated in coffee beans and F. verticillioides inoculated in corn seeds. An isolate of Muscodor albus was used as selection tool for VOC producing fungi. Among the 400 endophytic fungi isolates, 11 were able to grow in the presence of VOCs produced by M. albus. These fungi were identified as Muscodor spp. (9) and Simplicillium sp. according to searches in UNITE database using DNA sequences of internal transcribed spacer (ITS). The VOC's produced by endophytic fungi inhibited the growth the phytopathogenic fungi with different efficacies, compared to the control. The VOCs produced by Muscodor coffeanum (COAD 1842) showed fungicidal effect against A. ochraceus on coffee beans. Six endophytic fungi completely inhibited growth of F. verticillioides inoculated in corn seeds. This study demonstrates that the volatile-compound producing endophytic fungi, isolated from Coffea arabica, are promising sources of bioactive compounds.


Fungos endofíticos são uma fonte promissora para a descoberta de compostos com potencial biotecnológico. O objetivo deste estudo foi selecionar e identificar fungos endofíticos de Coffea arabica que produzem compostos orgânicos voláteis (COVs), avaliar o efeito dos compostos orgânicos voláteis produzido por fungos endofíticos sobre o crescimento de Rhizoctonia solani, Fusarium oxysporum, Phoma sp., Botrytis cinerea, Fusarium solani, Fusarium verticillioides, Cercospora coffeicola e Pestalotia longisetula e selecionar fungos endofíticos com potencial para controle biológico de Aspergillus ochraceus inoculado em grãos de café e F. verticillioides inoculado em sementes de milho. Um isolado de Muscodor albus foi utilizado como ferramenta de seleção para fungos endofíticos produtores de COVs. Dentre os 400 fungos endofíticos isolados, 11 foram capazes de crescer na presença de COVs produzidos por M. albus. Estes fungos foram identificados como Muscodor spp. (9) e Simplicillium sp. de acordo com pesquisas na base de dados UNITE usando sequências de DNA do espaçador transcrito interno (ITS). Os COVs produzidos por fungos endofíticos inibiram o crescimento dos fungos fitopatogênicos em comparação com o controle com diferentes eficácias. Os COVs produzidos por Muscodor coffeanum (COAD 1842) apresentou efeito fungicida contra A. ochraceus em grãos de café. Seis fungos endofíticos inibiram completamente o crescimento de F. verticillioides inoculado em sementes de milho. Este estudo demonstra que os fungos endofíticos produtores de compostos voláteis isolados de Coffea arabica são fontes promissoras de compostos bioativos.


Assuntos
Aspergillus , Coffea , Fungos , Fusarium
9.
IMA Fungus ; 7(1): 9-28, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27433438

RESUMO

Four new Asterolibertia species and a new variety of Cirsosia splendida, all found on native Cerrado plants, belonging to three host families are described, illustrated and named as: A. bahiensis sp. nov. on Erythroxylum sp. (Erythroxylaceae); A. barrinhensis sp. nov. on Diospyros burchellii (Ebenaceae); A. campograndensis sp. nov. on Hirtella glandulosa (Chrysobalanaceae); A. parinaricola sp. nov. on Parinari obtusifolia (Chrysobalanaceae); and Cirsosia splendida var. laevigata var. nov., showing both sexual and asexual morphs, on H. glandulosa and H. gracilipes (Chrysobalanaceae). Finally, A. licaniae is reported on a new host, H. gracilipes. Keys to all the known species of Asterolibertia and Cirsosia are included.

10.
Plant Dis ; 100(3): 561-568, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30688600

RESUMO

Coconut palm (Cocos nucifera L.) is one of the most important perennial tropical crops. Stem-end rot is the major postharvest disease of coconut in Brazil. The fungus Lasiodiplodia theobromae is the only species that has been reported to be associated with this disease. However, a comprehensive study elucidating the true identity of this pathogen with molecular tools has never been conducted. In recent years, new species of Lasiodiplodia have been proposed after molecular studies were performed, indicating the existence of a species complex. The aims of this research were to study the etiology of the postharvest stem-end rot of immature coconut based on a combination of morphological and phylogenetic analyses, to establish the phylogenetic position of such taxa, and to assess the pathogenicity of each taxon. Four species were identified: L. brasiliense, L. egyptiacae, L. pseudotheobromae, and L. theobromae. All of the species were distinguished morphologically and phylogenetically and were proven to be pathogenic to coconut following artificial inoculation. L. theobromae was the most common and the most aggressive species. This study represents the first report of three additional species of Lasiodiplodia as causal agents of postharvest stem-end rot of immature coconut in Brazil.

11.
Microbiol Res ; 181: 84-92, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26111593

RESUMO

Endophytic fungi are microorganisms that live within plant tissues without causing disease during part of their life cycle. With the isolation and identification of these fungi, new species are being discovered, and ecological relationships with their hosts have also been studied. In Glycine max, limited studies have investigated the isolation and distribution of endophytic fungi throughout leaves and roots. The distribution of these fungi in various plant organs differs in diversity and abundance, even when analyzed using molecular techniques that can evaluate fungal communities in different parts of the plants, such as denaturing gradient gel electrophoresis (DGGE). Our results show there is greater species richness of culturable endophytic filamentous fungi in the leaves G. max as compared to roots. Additionally, the leaves had high values for diversity indices, i.e. Simpsons, Shannon and Equitability. Conversely, dominance index was higher in roots as compared to leaves. The fungi Ampelomyces sp., Cladosporium cladosporioides, Colletotrichum gloeosporioides, Diaporthe helianthi, Guignardia mangiferae and Phoma sp. were more frequently isolated from the leaves, whereas the fungi Fusarium oxysporum, Fusarium solani and Fusarium sp. were prevalent in the roots. However, by evaluating the two communities by DGGE, we concluded that the species richness was higher in the roots than in the leaves. UPGMA analysis showed consistent clustering of isolates; however, the fungus Leptospora rubella, which belongs to the order Dothideales, was grouped among species of the order Pleosporales. The presence of endophytic Fusarium species in G. max roots is unsurprising, since Fusarium spp. isolates have been previously described as endophyte in other reports. However, it remains to be determined whether the G. max Fusarium endophytes are latent pathogens or non-pathogenic forms that benefit the plant. This study provides a broader knowledge of the distribution of the fungal community in G. max leaves and roots, and identifies the genetic relationships among the isolated species.


Assuntos
Endófitos/classificação , Fungos/classificação , Fungos/isolamento & purificação , Glycine max/microbiologia , Sequência de Bases , Biodiversidade , Brasil , DNA Ribossômico , Eletroforese em Gel de Gradiente Desnaturante/métodos , Endófitos/isolamento & purificação , Fungos/patogenicidade , Dados de Sequência Molecular , Filogenia , Folhas de Planta/microbiologia , Raízes de Plantas/microbiologia
12.
Mycologia ; 107(3): 532-57, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25800252

RESUMO

The genus Cosmospora includes nectrioid fungi that grow on polypores and xylariaceous fungi. The collections growing on xylariaceous fungi have been identified recently as Cosmospora viliuscula. In this paper the phylogeny and taxonomy of C. viliuscula are investigated. A phylogeny was generated with maximum likelihood and Bayesian inference methods applied to a three-partition dataset (ITS, 28S, MCM7-RPB1-TUB2). Based on these results, we demonstrate that Cosmospora viliuscula represents a diverse species complex comprising more than 10 species. Seven new species are described, including three single-strain lineages, and the sexual states of C. arxii and C. khandalensis are described for the first time. The sexual states of these fungi tend to have a high degree of morphological homoplasy, making it difficult to differentiate among them based on morphological characters alone. However, the apparent host specificity of species in this complex aide in the diagnosis of these fungi. In addition, the RPB1 marker provides sufficient resolution to distinguish these fungi.


Assuntos
Hypocreales/classificação , DNA Fúngico/genética , Hypocreales/genética , Hypocreales/crescimento & desenvolvimento , Dados de Sequência Molecular , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento
13.
Mycorrhiza ; 24(1): 55-64, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23812655

RESUMO

The composition and diversity of fungal communities associated with three endangered orchid species, Hadrolaelia jongheana, Hoffmannseggella caulescens, and Hoffmannseggella cinnabarina, found in different vegetation formations of the Atlantic Forest were determined by constructing clone libraries and by applying diversity and richness indices. Our results demonstrated the presence of Basidiomycetes. Sebacinales (81.61%) and Cantharellales (12.10%) were the dominant orders and are potential candidates for orchid mycorrhizal fungi. The Ascomycetes identified included the Helotiales (29.31%), Capnodiales (18.10%), and Sordariales (10.34%), among others. These orders may represent potentially endophytic fungi. A Shannon-Wiener diversity index (H') analysis showed a relatively high fungal community diversity associated with these tropical orchids. This diversity may offer greater flexibility in terms of the adaptation of the plants to changing environmental conditions and the potential facilitation of reintroduction programs. The Simpson diversity index values showed that all of the libraries included dominant species, and a LIBSHUFF analysis showed that the fungal communities were structurally different from each other, suggesting an influence of local factors on this diversity. This study offers important information for the development of conservation strategies for threatened and endemic species of Brazilian flora in an important and threatened hotspot.


Assuntos
Espécies em Perigo de Extinção , Endófitos/fisiologia , Fungos/fisiologia , Micorrizas/fisiologia , Orchidaceae/microbiologia , Raízes de Plantas/microbiologia , Árvores/microbiologia , Biodiversidade , Brasil , DNA Espaçador Ribossômico/genética , Endófitos/genética , Fungos/classificação , Fungos/genética , Micorrizas/classificação , Micorrizas/genética , Filogenia , Solo/química
14.
J Microbiol ; 51(1): 56-69, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23456713

RESUMO

Fungal endophytes were isolated from the leaves of soybean cultivars in Brazil using two different isolation techniques - fragment plating and the innovative dilution-to-extinction culturing - to increase the species richness, frequency of isolates and diversity. A total of 241 morphospecies were obtained corresponding to 62 taxa that were identified by analysis of the internal transcribed spacer (ITS) of the ribosomal DNA (rDNA). The Phylum Ascomycota predominated, representing 99% and 95.2% of isolates in the Monsoy and Conquista cultivars, respectively, whereas the Phylum Basidiomycota represented 1% and 4.8% of isolates, respectively. The genera Ampelomyces, Annulohypoxylon, Guignardia, Leptospora, Magnaporthe, Ophiognomonia, Paraconiothyrium, Phaeosphaeriopsis, Rhodotorula, Sporobolomyces, and Xylaria for the first time were isolated from soybean; this suggests that soybean harbours novel and highly diverse fungi. The yeasts genera Rhodotorula and Sporobolomyces (subphylum Pucciniomycotina) represent the Phylum Basidiomycota. The species richness was greater when both isolation techniques were used. The diversity of fungal endophytes was similar in both cultivars when the same isolation technique was used except for Hill's index, N1. The use of ITS region sequences allowed the isolates to be grouped according to Order, Class and Phylum. Ampelomyces, Chaetomium, and Phoma glomerata are endophytic species that may play potential roles in the biological control of soybean pathogens. This study is one of the first to apply extinction-culturing to isolate fungal endophytes in plant leaves, thus contributing to the development and improvement of this technique for future studies.


Assuntos
Biodiversidade , Endófitos/classificação , Endófitos/isolamento & purificação , Fungos/classificação , Fungos/isolamento & purificação , Glycine max/microbiologia , Brasil , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Endófitos/citologia , Endófitos/genética , Fungos/citologia , Fungos/genética , Dados de Sequência Molecular , Filogenia , Folhas de Planta/microbiologia , Análise de Sequência de DNA
15.
Plant Dis ; 97(4): 496-500, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30722252

RESUMO

Schinus terebinthifolius (Anacardiaceae), Brazilian peppertree (BP), is a major environmental weed in many tropical and subtropical areas of the globe, including Florida, Hawai'i, and Australia. This plant has been the target of a classical biocontrol project in the United States involving pathogens collected in Brazil for several years. A fungus was found in the Brazilian state of Espírito Santo causing leaf spots and severe foliage blight on BP. Examination of the morphology and internal transcribed spacer sequence analysis confirmed that the fungus is a strain of Corynespora cassiicola. Preliminary host-range tests involving 24 species, including 11 species in the family Anacardiaceae, were conducted with the fungus, and specificity toward BP was confirmed. Plants of Brazilian pepper tree from populations in Florida and Hawai'i included in the tests became severely diseased. Therefore, the recognition of a new forma specialis-Corynespora cassiicola f. sp. schinii-is proposed. The specificity of this forma specialis and the severity of the disease it caused in the field and under controlled conditions indicate that it has the potential for use as a biocontrol agent for BP in areas where it is an exotic invasive species.

16.
Mycologia ; 105(3): 697-711, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23233503

RESUMO

Continuing the study of black mildews in fragments of the Atlantic forest, three new species and five new records are described herein. Irenopsis luheae-grandiflorae, Meliola vicosensis and Meliola xylopia-sericiae are new species. Cecropia hololeuca, Piper gaudichaudianum and Trichilia lepidota are new hosts for Asteridiella leucosykeae, Asteridiella glabroides and Meliola trichiliae respectively. Asteridiella obesa and Meliola psychotriae var. chiococcae are reported for the first time from Brazil. The new species are described and illustrated based on light and scanning electron microscopy and tables with main characteristics of morphologically similar specimens with species collected in Viçosa are provided. Other species belonging to Meliolaceae collected on hosts belonging to the Annonaceae, Meliaceae and Tiliaceae in Brazil also were studied.


Assuntos
Doenças das Plantas/microbiologia , Saccharomycetales/classificação , Árvores/microbiologia , Annonaceae/microbiologia , Brasil , Meliaceae/microbiologia , Piperaceae/microbiologia , Rubiaceae/microbiologia , Rutaceae/microbiologia , Saccharomycetales/isolamento & purificação , Saccharomycetales/ultraestrutura , Tiliaceae/microbiologia , Urticaceae/microbiologia
17.
Mycologia ; 104(6): 1291-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22675047

RESUMO

The phylogenetic position of a new species of Anhellia (Myriangiales) was investigated by analysis of nucleotide sequences of ribosomal large subunit (LSU) and ITS regions. The new sequence was aligned with 28 sequences obtained from GenBank, including four species of Davidiellaceae (Capnodiales) used as outgroup. This study is the first attempt to resolve the placement of the genus Anhellia within Myriangiales. The genus Anhellia was strongly supported in Myriangiaceae by phylogenetic analyses. In addition, A. nectandrae sp. nov., collected on Nectandra rigida from a fragment of Atlantic forest in Brazil, is described, illustrated and a table with morphological features to all known Anhellia species is provided.


Assuntos
Ascomicetos/classificação , Magnoliopsida/microbiologia , Filogenia , Doenças das Plantas/microbiologia , Esporos Fúngicos/citologia , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Sequência de Bases , Brasil , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Magnoliopsida/citologia , Dados de Sequência Molecular , Folhas de Planta/microbiologia , Análise de Sequência de DNA , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/isolamento & purificação
18.
Mycologia ; 104(1): 121-37, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21914824

RESUMO

Five new species, two new varieties and three newly reported taxa belonging to the Meliolaceae were collected in fragments of Atlantic forest from Minas Gerais, Brazil, in association with native plants and are described and illustrated herein. The newly described species are Appendiculella eupatorii, Meliola cassiae-ferrugineae, M. mutisiae, M. peruiferae, M. vernaliae. The new varieties are M. garugae var. protii and M. paullinifolii var. rubiginosae. These taxa are reported in Brazil for the first time: Asteridiella cyclopoda, A. entebbeensis var. codiaei and Meliola pazschkeana var. macropoda. We studied other species belonging in Meliolaceae collected on hosts belonging to the Asteraceae, Burseraceae, Euphorbiaceae, Fabaceae (Caesalpinioideae and Papilionoideae) and Sapindaceae in Brazil.


Assuntos
Ascomicetos/classificação , Magnoliopsida/microbiologia , Doenças das Plantas/microbiologia , Árvores/microbiologia , Ascomicetos/isolamento & purificação , Asteraceae/microbiologia , Brasil , Burseraceae/microbiologia , Euphorbiaceae/microbiologia , Fabaceae/microbiologia , Sapindaceae/microbiologia , Clima Tropical
19.
Appl Biochem Biotechnol ; 165(2): 594-610, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21573756

RESUMO

The aim of this work was to have cellulase activity and hemicellulase activity screenings of endophyte Acremonium species (Acremonium zeae EA0802 and Acremonium sp. EA0810). Both fungi were cultivated in submerged culture (SC) containing L -arabinose, D -xylose, oat spelt xylan, sugarcane bagasse, or corn straw as carbon source. In solid-state fermentation, it was tested as carbon source sugarcane bagasse or corn straw. The highest FPase, endoglucanase, and xylanase activities were produced by Acremonium sp. EA0810 cultivated in SC containing sugarcane bagasse as a carbon source. The highest ß-glucosidase activity was produced by Acremonium sp. EA0810 cultivated in SC using D -xylose as carbon source. A. zeae EA0802 has highest α-arabinofuranosidase and α-galactosidase activities in SC using xylan as a carbon source. FPase, endoglucanase, ß-glucosidase, and xylanase from Acremonium sp. EA0810 has optimum pH and temperatures of 6.0, 55 °C; 5.0, 70 °C; 4.5, 60 °C; and 6.5, 50 °C, respectively. α-Arabinofuranosidase and α-galactosidase from A. zeae EA0802 has optimum pH and temperatures of 5.0, 60 °C and 4.5, 45 °C, respectively. It was analyzed the application of Acremonium sp. EA0810 to hydrolyze sugarcane bagasse, and it was achieved 63% of conversion into reducing sugar and 42% of conversion into glucose.


Assuntos
Acremonium/enzimologia , Celulases/metabolismo , Celulose/metabolismo , Glicosídeo Hidrolases/metabolismo , Microbiologia Industrial/métodos , Saccharum/metabolismo , alfa-Galactosidase/metabolismo , Biocombustíveis , Celulases/química , Fermentação , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Glucose/biossíntese , Glicosídeo Hidrolases/química , Concentração de Íons de Hidrogênio , Hidrólise , Temperatura , Xilanos/metabolismo , Xilose/metabolismo , Zea mays/metabolismo , alfa-Galactosidase/química
20.
Mycologia ; 102(1): 69-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20120231

RESUMO

Miconia calvescens (Melastomataceae) is a shrub or small tree native to the Neotropics that has become one of the worst invaders of forest ecosystems, particularly in Pacific islands such as Hawaii and French Polynesia. It has been a target for biological control for more than 10 y, both with arthropod and pathogen natural enemies. Until now Colletotrichum gloeosporioides f. sp. miconiae was the only organism to be used in biological control against this weed. This fungus was introduced both in Hawaii and in French Polynesia in the late 1990s/early 2000s, where it has caused some damage to the weed, but it became evident that additional agents are needed to achieve adequate control. Exploratory surveys for plant pathogens as potential biocontrol agents of M. calvescens were undertaken in Brazil, Costa Rica and Ecuador and yielded a diverse list of pathogens, including one phytoplasma, two nematodes, one oomycete and numerous fungi. A study including the description of five fungal species found attacking M. calvescens was published recently. Herein the following additional fungi also belonging to the mycobiota of M. calvescens are described: Hyalosphaera ornata sp. nov, Microsphaeropsis miconiae sp. nov., Myrothecium miconiae sp. nov., Phyllachora miconiiphila sp. nov., as well as Hyalosphaera miconiae, Lembosia melastomatum and Microsphaeropsis clidemiae, which are recorded here for the first time on this host. Although preliminary our observations of damage to M. calvescens caused by these seven fungal species did not indicate any potential for use in classical biological control.


Assuntos
Fungos/classificação , Melastomataceae/microbiologia , Controle Biológico de Vetores , Ascomicetos/classificação , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/patogenicidade , Ascomicetos/ultraestrutura , Brasil , Equador , Fungos/crescimento & desenvolvimento , Fungos/patogenicidade , Fungos/ultraestrutura , Melastomataceae/crescimento & desenvolvimento , Melastomataceae/ultraestrutura , Microscopia Eletrônica de Varredura , Doenças das Plantas/microbiologia
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