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1.
Braz J Microbiol ; 55(3): 2845-2854, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38951477

RESUMO

Cotton (Gossypium hirsutum, Malvaceae) is the most important fiber crop in the world. There are published records of many fungal pathogens attacking Gossypium spp., causing numerous diseases, including powdery mildews. Recently, in 2022, non-cultivated spontaneous G. hirsutum plants bearing powdery mildews symptoms were found at roadsides in two municipalities of the state of Minas Gerais (Brazil): Varginha and Ubá. Such localities are situated ca. 260 km apart, suggesting a broader distribution of this fungus-host association in Brazil. Samples were taken to the laboratory, and an Ovulariopsis-like, asexual stage of Phyllactinia, was identified forming amphigenous colonies, that were more evident, white and cottony, abaxially. Morphological and molecular data- of the ITS and LSU regions- have shown that colonies from those two samples were of the same fungus species, belonging to a previously unknown species of Erysiphaceae (Ascomycota). The fungus fits into the Phyllactinia clade and is described herein as the new species Phyllactinia gossypina sp. nov. This new species belongs to the 'basal Phyllactinia group', a lineage that includes species known only from the Americas. This report expands the list of pathogenic fungi on cotton. It is early to anticipate whether this new powdery mildew represents a threat to cultivated cotton, which is a major crop in Brazil. Nevertheless, further studies about its infectivity to commercial cotton varieties are recommended, since all known Erysiphaceae are specialized obligate plant parasites and several species cause major losses to important crops.


Assuntos
Gossypium , Filogenia , Doenças das Plantas , Gossypium/microbiologia , Brasil , Doenças das Plantas/microbiologia , Ascomicetos/classificação , Ascomicetos/isolamento & purificação , Ascomicetos/genética , Ascomicetos/fisiologia , DNA Fúngico/genética
2.
Braz J Microbiol ; 55(2): 1569-1585, 2024 Jun.
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.


Assuntos
Cavernas , DNA Fúngico , Filogenia , Cavernas/microbiologia , Brasil , DNA Fúngico/genética , Animais , Carbonato de Cálcio , Acremonium/genética , Acremonium/classificação , Acremonium/isolamento & purificação
3.
Artigo em Inglês | MEDLINE | ID: mdl-38194255

RESUMO

In this study, a novel genus is proposed, Scaptona, with a novel species, Scaptona ramosa, isolated from nests of stingless bees (Scaptotrigona sp.). The taxonomic novelty was determined by the phylogenetic analysis of DNA sequences from the internal transcribed spacer regions, small subunit rRNA (18S rRNA), large subunit rRNA (28S rRNA) and the RNA polymerase II second-largest subunit gene (RPB2) and paired with our morphological studies. Based on this single species, Scaptona is characterized by greyish green to dark grey colonies, densely and profusely branched conidiophores and single-celled, variously shaped hyaline conidia. Scaptona ramosa constitutes a distinct, well-supported lineage within Cephalothecaceae and can be clearly distinguished from other genera both by DNA sequence analysis and morphological traits. The holotype of S. ramosa is URM 95352. The ex-type strain has been deposited in the Micoteca URM culture collection as URM 8721T and URM 8722. The MycoBank accession number is MB 849456 for the genus and MB 849456 for the species.


Assuntos
Ácidos Graxos , Animais , Abelhas , Filogenia , Análise de Sequência de DNA , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , Ácidos Graxos/química , RNA Ribossômico 18S
4.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469301

RESUMO

Abstract Endophytic fungi are a ubiquituos group that colonize all plant species on earth. Studies comparing the location of endophytic fungi within the leaves and the sampling time in Manihot esculenta Crantz (cassava) are limited. In this study, mature leaves of M. esculenta from Panama were collected in order to compare the cultivable diversity of endophytic fungi and to determine their distribution within the leaves. A total of one hundred sixty endophytes belonging to 97 species representing 13 genera and 8 morphospecies determined as mycelia sterilia that containing 63 isolates were isolated. Cladosporium, Nigrospora, Periconia, and mycelia sterilia 1 and 3 were the most predominant isolated endophytes. We detected that endophytes varied across the sampling time, but not amongst locations within leaves. The endophytes composition across sampling and the location of endophytes within leaf was similar, except for Periconia and mycelia sterilia 3 and 7. The data generated in this study contribute to the knowledge on the biodiversity of endophytic fungi in Panama, and establish the bases for future research focused on understanding the function of endophytes in M. esculenta crops.


Resumo Os fungos endofíticos são um grupo ubiquituo que colonizam todas as espécies de plantas na terra. Os estudos que comparam a localização dos fungos endofíticos dentro das folhas de Manihot esculenta Crantz (mandioca) e o tempo de amostragem são muito escassos. Neste estudo, folhas maduras de M. esculenta foram coletadas do Panamá com a finalidade de comparar a diversidade cultivável de endófitos e determinar sua distribuição dentro das folhas. Um total de 170 endófitos foram isolados de 97 espécies que representam 13 gêneros e 8 morfoespécies determinadas como micélios esterilizados contendo 63 isolados. Os fungos Cladosporium, Nigrospora, Periconia e mycelia sterilia 1 e 3 foram os isolados mais predominantes. Também detectamos que os endófitos variaram ao longo do tempo de amostragem, mas não entre os locais dentro das folhas. A composição de endófitos na amostragem e localização de endófitos dentro da folha foi semelhante, exceto para Periconia e mycelia sterilia 3 e 7. Os dados gerados neste estudo contribuem para o conhecimento da biodiversidade de fungos endofíticos no Panamá e estabelecem as bases para pesquisas sobre o entendimento da função de endófitos em culturas de M. esculenta.

5.
Biota Neotrop. (Online, Ed. ingl.) ; 24(2): e20231603, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1564049

RESUMO

Abstract Endophytic microorganisms are those that inhabit the interior of plant tissues and organs without causing damage to the plant, triggering a mutualistic interaction. These endophytes are known to produce compounds with various applications in the areas of biotechnology, pharmaceutical industry and agriculture; therefore, molecular methods are used to investigate the phylogeny of these organisms. The Brazilian Cerrado is the second largest biome in Brazil and is considered a hotspot, with a high diversity of endemic fauna and flora. The objective of this work was to analyze, through in silico analysis, the phylogeny of cultivable endophytic fungi isolated from plants found in the Brazilian Cerrado biome. A search was carried out for articles that worked with endophytes in the period between 2012 and 2022. The dendrogram was generated using the Neighbor-joining method based on the ITS1-5.8S-ITS2 conserved region obtained by GenBank codes of isolated endophytes. The genera Xylaria, Diaporthe, and Colletotrichum were isolated in more than three plants in the seven articles found. Most of the articles found related to the biodiversity of endophytic fungi from the Brazilian Cerrado aim at the bioprospecting of bioactive compounds, through culture-dependent methods; as such, a part of endophytic diversity may be lost due to the inability of certain endophytes to grow in artificial media. In silico analysis can assist in the investigation of phylogenetic relationships between endophytic fungi and has the potential to guide future work aimed at prospecting for bioactive compounds, phylogenetic identification, or biodiversity of this group of endophytes.


Resumo Microrganismos endofíticos são aqueles que vivem no interior de tecidos e órgãos vegetais sem causar dano à planta, desencadeando uma interação mutualística. Esses endófitos são conhecidos por produzir compostos com diversas aplicações nas áreas de biotecnologia, indústria farmacêutica e agricultura; logo, métodos moleculares são utilizados para investigar a filogenia destes organismos. O Cerrado brasileiro é o segundo maior bioma do Brasil e é considerado um hotspot, com uma alta diversidade de fauna e flora endêmica. O objetivo deste trabalho foi analisar, por meio da análise in silico, a filogenia de fungos endofíticos cultiváveis isolados de plantas encontradas no bioma Cerrado brasileiro. Foi realizada uma busca por artigos que trabalharam com endófitos no período entre 2012 e 2022. O dendrograma foi gerado usando o método Neighbor-joining baseado na região conservada ITS1-5.8S-ITS2 obtida pelos códigos GenBank de endófitos isolados. Os gêneros Xylaria, Diaporthe e Colletotrichum foram isolados em mais de três plantas nos sete artigos encontrados. A maior parte dos artigos encontrados relacionados à biodiversidade de fungos endofíticos do Cerrado brasileiro visam à bioprospecção de compostos bioativos, através de métodos dependentes de cultura; como tal, uma parte da diversidade endofítica pode ser perdida devido à incapacidade de certos endófitos crescerem em meios artificiais. A análise in silico pode auxiliar na investigação das relações filogenéticas entre fungos endofíticos e tem potencial para orientar trabalhos futuros voltados à prospecção de compostos bioativos, identificação filogenética ou biodiversidade deste grupo de endófitos.

6.
Braz. j. biol ; 84: e253156, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355904

RESUMO

Abstract Endophytic fungi are a ubiquituos group that colonize all plant species on earth. Studies comparing the location of endophytic fungi within the leaves and the sampling time in Manihot esculenta Crantz (cassava) are limited. In this study, mature leaves of M. esculenta from Panama were collected in order to compare the cultivable diversity of endophytic fungi and to determine their distribution within the leaves. A total of one hundred sixty endophytes belonging to 97 species representing 13 genera and 8 morphospecies determined as mycelia sterilia that containing 63 isolates were isolated. Cladosporium, Nigrospora, Periconia, and mycelia sterilia 1 and 3 were the most predominant isolated endophytes. We detected that endophytes varied across the sampling time, but not amongst locations within leaves. The endophytes composition across sampling and the location of endophytes within leaf was similar, except for Periconia and mycelia sterilia 3 and 7. The data generated in this study contribute to the knowledge on the biodiversity of endophytic fungi in Panama, and establish the bases for future research focused on understanding the function of endophytes in M. esculenta crops.


Resumo Os fungos endofíticos são um grupo ubiquituo que colonizam todas as espécies de plantas na terra. Os estudos que comparam a localização dos fungos endofíticos dentro das folhas de Manihot esculenta Crantz (mandioca) e o tempo de amostragem são muito escassos. Neste estudo, folhas maduras de M. esculenta foram coletadas do Panamá com a finalidade de comparar a diversidade cultivável de endófitos e determinar sua distribuição dentro das folhas. Um total de 170 endófitos foram isolados de 97 espécies que representam 13 gêneros e 8 morfoespécies determinadas como micélios esterilizados contendo 63 isolados. Os fungos Cladosporium, Nigrospora, Periconia e mycelia sterilia 1 e 3 foram os isolados mais predominantes. Também detectamos que os endófitos variaram ao longo do tempo de amostragem, mas não entre os locais dentro das folhas. A composição de endófitos na amostragem e localização de endófitos dentro da folha foi semelhante, exceto para Periconia e mycelia sterilia 3 e 7. Os dados gerados neste estudo contribuem para o conhecimento da biodiversidade de fungos endofíticos no Panamá e estabelecem as bases para pesquisas sobre o entendimento da função de endófitos em culturas de M. esculenta.


Assuntos
Ascomicetos , Manihot , Filogenia , Folhas de Planta , Biodiversidade , Endófitos , Fungos
7.
Bot Stud ; 64(1): 31, 2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37891334

RESUMO

BACKGROUND: The genus Camillea was created in 1849 from collections made in French Guiana with eight species included. Numerous species assigned to Camillea were subsequently discovered, especially in the forests of the Amazon basin, but new discoveries have not been reported from French Guiana since 1849. Recent fieldwork in French Guiana has begun to fill this gap by identifying five new species, most of which were collected in the vicinity of Saül village. RESULTS: Based on macro- and micromorphological study of their stromata, including SEM images of ascospore wall ornamentation, five new species were recognized, including C. cribellum, C. heterostomoides, C. nitida, C. rogersii and C. saulensis. Cultures could be obtained for C. heterostomoides and C. rogersii, and ITS and LSU sequences were obtained for all of the five new species. Camillea heterostoma and its variety microspora were shown to be conspecific. Provisional molecular phylogenetic analyses support the possible reinstatement of Hypoxylon melanaspis, currently regarded as merely an applanate form of C. leprieurii. CONCLUSION: The current study is based on a relatively limited fieldwork in its duration and sampling area but was able to substantially increase the number of Camillea species known from French Guiana. This augurs an exceptional and still unknown diversity of the genus in this area and by extension in the adjacent neotropical forests.

8.
J Fungi (Basel) ; 9(9)2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37755041

RESUMO

The tropical montane cloud forest is the most diverse and threatened vegetation type in Mexico. In the last decade, the number of described Ascomycetes species has notably increased, reaching more than 1300 species. This study describes six new species based on their molecular and morphological characteristics. Our results suggest that Mexico has the highest number of described species in the Neotropics. However, many other Mexican lineages still need to be described.

9.
J Invertebr Pathol ; 200: 107956, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37356705

RESUMO

A total of 53 anamorphic strains of Brazilian Cordyceps species currently maintained in a government-owned culture collection, were reassessed for diversity and species identity using multi-loci-based phylogenetic methods. The strains used in this study were originally obtained from soil samples or were isolated from insects of the orders Hemiptera, Lepidoptera, Coleoptera and Diptera, mostly from agricultural sites. A Bayesian phylogenetic tree was constructed based on a concatenation of five loci (ITS, LSU, RPB1, RPB2 and TEF). In a few cases of ambiguity, morphological traits were also considered for species delimitations. Considerable variability within the set of strains was detected and six Cordyceps species were identified: C. amoenerosea, C. fumosorosea, C. javanica, C. tenuipes and, for the first time, C. brevistroma and C. spegazzinii are reported in Brazil. Four other taxonomically equivocal groups, closely related to other known taxa (C. amoenerosea, C. cateniannulata, C. polyarthra and C. spegazzinii), were also recognized, although further studies will be required to confirm their identifications or their descriptions as new species. Cordyceps javanica was the most common species in our dataset, originally isolated from soil and several different insect orders, and includes 17 strains from the whitefly, Bemisia tabaci. Interestingly, strains previously identified as C. fumosorosea based on morphology and growth characteristics, were shown to be C. javanica, including the active ingredients of some commercial mycoinsecticides. Cordyceps farinosa, usually mentioned in the literature as occurring in Brazil, was not found in our study. Since most strains were from insect crop pests, further studies with hosts from non-agricultural settings or from environmental samples would be advisable for a deeper understanding of the occurrence of anamorphic Cordyceps in Brazil.


Assuntos
Cordyceps , Hemípteros , Hypocreales , Animais , Cordyceps/genética , Brasil , Filogenia , Teorema de Bayes , Insetos
10.
J Fungi (Basel) ; 9(5)2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37233219

RESUMO

Elucidating the complex relationship between plants and endophytic fungi is very important in order to understand the maintenance of biodiversity, equity, stability, and ecosystem functioning. However, knowledge about the diversity of endophytic fungi from species of the native Brazilian Cerrado biome is poorly documented and remains largely unknown. These gaps led us to characterize the diversity of Cerrado endophytic foliar fungi associated with six woody species (Caryocar brasiliense, Dalbergia miscolobium, Leptolobium dasycarpum, Qualea parviflora, Ouratea hexasperma, and Styrax ferrugineus). Additionally, we investigated the influence of host plant identities on the structure of fungal communities. Culture-dependent methods coupled with DNA metabarcoding were employed. Irrespective of the approach, the phylum Ascomycota and the classes Dothideomycetes and Sordariomycetes were dominant. Using the cultivation-dependent method, 114 isolates were recovered from all the host species and classified into more than 20 genera and 50 species. Over 50 of the isolates belonged to the genus Diaporthe, and were distributed into more than 20 species. Metabarcoding revealed the phyla Chytridiomycota, Glomeromycota, Monoblepharomycota, Mortierellomycota, Olpidiomycota, Rozellomycota, and Zoopagomycota. These groups are reported for the first time as components of the endophytic mycobiome of Cerrado plant species. In total, 400 genera were found in all host species. A unique leaf endophytic mycobiome was identified in each host species, which differed not only by the distribution of fungal species, but also by the abundance of shared species. These findings highlight the importance of the Brazilian Cerrado as a reservoir of microbial species, and emphasize how endophytic fungal communities are diversified and adapted.

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