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Chlorosplenium is a small genus comprising five species of inoperculate discomycetes in the order Helotiales (Leotiomycetes) often recognizable by their bright yellowish-green colors and gregarious growth on wood. In this study, we describe five new species-C. aotearoa, C. australiense, C. cusucoense, C. epimorsicum, and C. hawaiiense-based on a combination of recent fieldwork and examination of previously collected fungarium specimens. We use an integrative taxonomic approach to support the distinction of new species, incorporating morphology and DNA sequence data with biogeography. Macro- and micromorphological features of apothecia for all species and culture characteristics for four of the five new species are documented. A multilocus phylogeny based on nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2, partial large subunit nuc ribosomal DNA (28S nuc rDNA), and A-B regions of the largest subunit of RNA polymerase II (RPB1) gene is presented. Additionally, we report Chlorosplenium chlora from Europe for the first time and expand our knowledge of the diversity and distributions of species in this genus in America, Australia, and New Zealand.
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Species of the ectomycorrhizal (ECM) family Cortinariaceae (Agaricales, Agaricomycetes, Basidiomycota) have long been considered impoverished or absent from lowland tropical rainforests. Several decades of collecting in forests dominated by ECM trees in South America's Guiana Shield is countering this view, with discovery of numerous Cortinariaceae species. To date, ~12 morphospecies of this family have been found in the central Pakaraima Mountains of Guyana. Here, we describe three of these as new species of Cortinarius and two as new species of Phlegmacium from forests dominated by the ECM tree genera Dicymbe (Fabaceae subfam. Detarioideae), Aldina (Fabaceae subfam. Papilionoideae), and Pakaraimaea (Cistaceae). Macromorphological, micromorphological, habitat, and DNA sequence data are provided for each new species.
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Sphaerellopsis species are putative hyperparasites of rust fungi and may be promising biological control agents (BCA) of rust diseases. However, few detailed studies limit potential BCA development in Sphaerellopsis. Here, we explored the biogeography, host-specificity, and species diversity of Sphaerellopsis and examined the early infection stage of one species, S. macroconidialis, to infer its trophic status. We randomly screened 5,621 rust specimens spanning 99 genera at the Arthur Fungarium for the presence of Sphaerellopsis. We identified 199 rust specimens infected with Sphaerellopsis species on which we conducted morphological and multi-locus phylogenetic analyses. Five Sphaerellopsis species were recovered, infecting a total of 122 rust species in 18 genera from 34 countries. Sphaerellopsis melampsorinearum sp. nov. is described as a new species based on molecular phylogenetic data and morphological features of the sexual and asexual morphs. Sphaerellopsis paraphysata was the most commonly encountered species, found on 77 rust specimens, followed by Sphaerellopsis macroconidialis on 56 and S. melampsorinearum on 55 examined specimens. The type species, Sphaerellopsis filum, was found on 12 rust specimens and Sphaerellopsis hakeae on a single specimen. We also recovered and documented for the first time, the sexual morph of S. macroconidialis, from a specimen collected in Brazil. Our data indicate that Sphaerellopsis species are not host specific and furthermore that most species are cosmopolitan in distribution. However, S. paraphysata is more abundant in the tropics, and S. hakeae may be restricted to Australia. Finally, we confirm the mycoparasitic strategy of S. macroconidialis through in-vitro interaction tests with the urediniospores of Puccinia polysora. Shortly after germination, hyphae of S. macroconidialis began growing along the germ tubes of P. polysora and coiling around them. After 12 days of co-cultivation, turgor loss was evident in the germ tubes of P. polysora, and appressorium-like structures had formed on urediniospores. The interaction studies indicate that Sphaerellopsis species may be more effective as a BCA during the initial stages of rust establishment.
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BACKGROUND: The burden of maternal and child mortality is high in the Democratic Republic of the Congo (DRC). While health workers (HWs) with adequate knowledge and practice of maternal and child health (MCH) are crucial to reduce this burden, the skill level of HWs in charge of MCH in the DRC is currently insufficient. This study aimed to assess the knowledge and practice of HWs towards MCH in Kasai and Maniema, two DRC provinces with very high maternal mortality ratios and under-5 mortality rates. METHODS: This cross-sectional study was conducted in 96 health facilities of Kasai and Maniema provinces in 2019. All HWs in charge of MCH were eligible for the study. Data were collected using a structured questionnaire containing 76 questions on knowledge and practice of MCH. Analyses were performed using the Wilcoxon-Mann-Whitney test, Kendall's correlation test, and a multivariate linear mixed regression model. RESULTS: Among participating HWs, 42.6% were A2 nurses (lowest qualification), 81.9% had no up-to-date training in MCH, and 48.4% had only 1-5 years of experience in MCH. In the two provinces combined, about half of HWs had poor knowledge (50.6%) and poor practice (53.3%) of MCH. Knowledge and practice scores were higher in Maniema than in Kasai (P < 0.001). Good knowledge and practice scores were significantly associated with high qualification (P = 0.001), continuing up-to-date training in MCH (P = 0.009), and 6 years of experience or more in MCH (P = 0.01). CONCLUSION: In Maniema and Kasai provinces, about half of HWs had poor knowledge and poor practice of MCH. The conversion of A1 nurses into midwives as well as the provision of up-to-date training in MCH, supervision, and mentorship could improve the skill level of HWs and could thus reduce the burden of MCH in the DRC.
This study assessed the knowledge and practice of health workers (HWs) towards maternal and child health (MCH) in Kasai and Maniema, two provinces of the Democratic Republic of the Congo (DRC) with very high maternal and child mortality rates. About half of surveyed HWs had poor knowledge and poor practice of MCH. Good knowledge and good practice were associated with high qualification, up-to-date training, and 6 years of experience or more in MCH. The conversion of A1 nurses into midwives as well as the provision of up-to-date training in MCH, supervision, and mentorship could improve the skill level of HWs and could thus reduce the burden of MCH in the DRC.
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Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde , Humanos , Estudos Transversais , República Democrática do Congo , Feminino , Adulto , Masculino , Serviços de Saúde Materno-Infantil/normas , Saúde da Criança , Saúde Materna , Pessoa de Meia-Idade , GravidezRESUMO
South Africa has an indigenous rust (Pucciniales) funga of approximately 460 species. This funga was sampled with species from as many genera as possible. The nuclear ribosomal large subunit (28S) region was amplified from samples representing 110 indigenous species, as well as the small subunit (18S) region and the cytochrome c oxidase subunit 3 (CO3) in some cases, and these were used in phylogenetic analyses. One new species is described, 12 new combinations made, six names reinstated, and two life history connections made. The life histories of this funga were summarized; it is dominated by species with contracted life histories. The majority of species are autoecious, with a small proportion being heteroecious. Of the autoecious species, many will likely be homothallic with no spermagonia. A shortened life history with homothallism allows for a single basidiospore infection to initiate a local population buildup under the prevailing unpredictable climatic conditions. Suggestions are made as to the possible origin of this funga based on the development of the modern South African flora. It is postulated that the rusts of South Africa are of relatively recent origin, consisting of three groups. Firstly, there is an African tropical element with members of the Mikronegerineae (Hemileia), the Sphaerophragmiaceae (Puccorchidium, Sphaerophragmium), and certain Uredinineae (Stomatisora). Their immediate ancestors likely occurred in the tropical forests of Africa during the Paleogene. Secondly, there is a pantropical element including the Raveneliaceae (e.g., Diorchidium, Maravalia, Ravenelia sensu lato, Uropyxis). This likely diversified during the Neogene, when the mimosoids became the dominant trees of the developing savannas. Thirdly, the Pucciniaceae invaded Africa as this continent pushed northward closing the Tethys Sea. They diversified with the development of the savannas as these become the dominant habitat in most of Africa, and are by far the largest component of the South African rust funga.
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Basidiomycota , DNA Fúngico , Filogenia , África do Sul , Basidiomycota/genética , Basidiomycota/classificação , DNA Fúngico/genética , Análise de Sequência de DNA , RNA Ribossômico 28S/genética , DNA Ribossômico/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , RNA Ribossômico 18S/genéticaRESUMO
The porcini mushroom family Boletaceae is a diverse, widespread group of ectomycorrhizal (ECM) mushroom-forming fungi that so far has eluded intrafamilial phylogenetic resolution based on morphology and multilocus data sets. In this study, we present a genome-wide molecular data set of 1764 single-copy gene families from a global sampling of 418 Boletaceae specimens. The resulting phylogenetic analysis has strong statistical support for most branches of the tree, including the first statistically robust backbone. The enigmatic Phylloboletellus chloephorus from non-ECM Argentinian subtropical forests was recovered as a new subfamily sister to the core Boletaceae. Time-calibrated branch lengths estimate that the family first arose in the early to mid-Cretaceous and underwent a rapid radiation in the Eocene, possibly when the ECM nutritional mode arose with the emergence and diversification of ECM angiosperms. Biogeographic reconstructions reveal a complex history of vicariance and episodic long-distance dispersal correlated with historical geologic events, including Gondwanan origins and inferred vicariance associated with its disarticulation. Together, this study represents the most comprehensively sampled, data-rich molecular phylogeny of the Boletaceae to date, establishing a foundation for future robust inferences of biogeography in the group.
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Agaricales , Genoma Fúngico , Filogenia , Agaricales/genética , Agaricales/classificação , Agaricales/isolamento & purificação , Sequenciamento Completo do Genoma , Micorrizas/genética , Micorrizas/classificação , FilogeografiaRESUMO
Rust fungi (Pucciniales, Basidiomycota) are a species-rich (ca. 8000 species), globally distributed order of obligate plant pathogens. Rust species are host-specific, and as a group they cause disease on many of our most economically and/or ecologically significant plants. As such, the ability to accurately and rapidly identify these fungi is of particular interest to mycologists, botanists, agricultural scientists, farmers, quarantine officials, and associated stakeholders. However, the complexities of the rust life cycle, which may include production of up to five different spore types and alternation between two unrelated host species, have made standard identifications, especially of less-documented spore states or alternate hosts, extremely difficult. The Arthur Fungarium (PUR) at Purdue University is home to one of the most comprehensive collections of rust fungi in the world. Using material vouchered in PUR supplemented with fresh collections we generated DNA barcodes of the 28S ribosomal repeat from > 3700 rust fungal specimens. Barcoded material spans 120 genera and > 1100 species, most represented by several replicate sequences. Barcodes and associated metadata are hosted in a publicly accessible, BLAST searchable database called Rust HUBB (Herbarium-based Universal Barcode Blast) and will be continuously updated.
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As part of a long-term study aiming to isolate and identify yeast species that inhabit the surface of leaves and fruits of native fine-aroma cacao in the department of Amazonas, Peru, we obtained multiple isolates of Hannaella species. Yeasts of the genus Hannaella are common inhabitants of the phyllosphere of natural and crop plants. On the basis of morphological, and physiological characteristics, and sequence analysis of the D1/D2 domains of the large subunit rRNA gene (LSU) and the internal transcribed spacer region (ITS), we identified five species of Hannaella from the phyllosphere of Peruvian cacao. Four have been previously described: H. phyllophila (isolates KLG-073, KLG-091), H. pagnoccae (KLG-076), H. sinensis (KLG-121), and H. taiwanensis (KLG-021). A fifth, represented by eight isolates (KLG-034, KLG-063, KLG-074, KLG-078, KLG-79, KLG-082, KLG-084, KLG-085), is not conspecific with any previously described Hannaella species, and forms the sister clade to H. surugaensis in the phylogenetic analysis. It has 2.6-3.9% (18-27 substitutions, 2-4 deletions, and 1-3 insertions in 610-938 bp-long alignments), and 9.8-10.0% nucleotide differences (37 substitutions and 14 insertions in 511-520 bp-long alignments) in the LSU and ITS regions, respectively, to H. surugaensis type strain, CBS 9426. Herein, the new species Hannaella theobromatis sp. nov. is described and characterised. The species epithet refers to its epiphytic ecology on its host Theobroma cacao.
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Basidiomycota , Cacau , Cacau/genética , Filogenia , Peru , DNA Espaçador Ribossômico/genética , Frutas , Folhas de Planta , Basidiomycota/genética , DNA Fúngico/genética , Análise de Sequência de DNA , Técnicas de Tipagem Micológica , TailândiaRESUMO
Fungi are integral to well-functioning ecosystems, and their broader impact on Earth systems is widely acknowledged. Fossil evidence from the Rhynie Chert (Scotland, UK) shows that Fungi were already diverse in terrestrial ecosystems over 407-million-years-ago, yet evidence for the occurrence of Dikarya (the subkingdom of Fungi that includes the phyla Ascomycota and Basidiomycota) in this site is scant. Here we describe a particularly well-preserved asexual fungus from the Rhynie Chert which we examined using brightfield and confocal microscopy. We document Potteromyces asteroxylicola gen. et sp. nov. that we attribute to Ascomycota incertae sedis (Dikarya). The fungus forms a stroma-like structure with conidiophores arising in tufts outside the cuticle on aerial axes and leaf-like appendages of the lycopsid plant Asteroxylon mackiei. It causes a reaction in the plant that gives rise to dome-shaped surface projections. This suite of features in the fungus together with the plant reaction tissues provides evidence of it being a plant pathogenic fungus. The fungus evidently belongs to an extinct lineage of ascomycetes that could serve as a minimum node age calibration point for the Ascomycota as a whole, or even the Dikarya crown group, along with some other Ascomycota previously documented in the Rhynie Chert.
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Ascomicetos , Ecossistema , Plantas/microbiologia , Fósseis , EscóciaRESUMO
Fungi are among the most biodiverse organisms in the world. Accurate species identification is imperative for studies on fungal ecology and evolution. The internal transcribed spacer (ITS) rDNA region has been widely accepted as the universal barcode for fungi. However, several recent studies have uncovered intragenomic sequence variation within the ITS in multiple fungal species. Here, we mined the genome of 2414 fungal species to determine the prevalence of intragenomic variation and found that the genomes of 641 species, about one-quarter of the 2414 species examined, contained multiple ITS copies. Of those 641 species, 419 (â¼65%) contained variation among copies revealing that intragenomic variation is common in fungi. We proceeded to show how these copies could result in the erroneous description of hundreds of fungal species and skew studies evaluating environmental DNA (eDNA) especially when making diversity estimates. Additionally, many genomes were found to be contaminated, especially those of unculturable fungi.
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Early in the COVID-19 pandemic, substantial disruptions in personal protective equipment (PPE) supply chains forced healthcare systems to become resourceful to ensure PPE availability for healthcare workers. Most worrisome was the global shortage of N95 respirators. In response, a collaboration between the Department of Infection Control and Healthcare Epidemiology and the Department of Biosafety at the University of Texas Medical Branch developed a PPE recycling program guaranteeing an adequate supply of respirators for frontline staff. The team successfully developed and implemented a novel workflow that included validated decontamination procedures, education, and training programs as well as transportation, labeling, and storage logistics. In total, 15,995 respirators of various types and sizes were received for recycling. Of these, 12,752 (80%) were recycled. Following the program's implementation, we surveyed 134 frontline healthcare workers who overwhelmingly graded our institution's culture of safety positively. Overall impressions of the N95 respirator recycling program were mixed, although interpretation of those results was limited by a lower survey response rate. In an era of increasing health security threats, innovative recycling programs like this one may serve as a model for other health systems to respond to future PPE supply chain disruptions.
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COVID-19 , Humanos , Respiradores N95 , SARS-CoV-2 , Descontaminação/métodos , Pandemias , Pessoal de SaúdeRESUMO
The Neotropics have recently emerged as an important region for studies of tropical ectomycorrhizal (ECM) fungi. Specific neotropical areas with high ECM host tree densities have ECM fungal diversities rivaling those of higher-latitude forests. Some forests of the Guiana Shield are dominated by endemic ECM trees of the Fabaceae, including species of Dicymbe (subfam. Detarioideae), Aldina (subfam. Papilionoideae), and Pakaraimaea (Cistaceae). One of the most species-rich ECM fungal families present in each of these systems is Russulaceae. Long-term sampling in forests in Guyana's Pakaraima Mountains has revealed a number of species of the Russulaceae genera Lactarius, Lactifluus, and Russula. In this study, we document a previously unknown, distinct lineage of Lactarius subg. Plinthogalus containing eight species from the Guiana Shield. Here, we describe five of these species from Guyana as new to science: Lactarius humiphilus, Lactarius mycenoides, Lactarius guyanensis, Lactarius dicymbophilus, and Lactarius aurantiolamellatus. Morphological descriptions, habit, habitat, and known distribution are provided for each new species. Sequence data for the barcode internal transcribed spacer (ITS) locus are provided for types and most other collections of the new taxa, and a molecular phylogenetic analysis based on the ITS, 28S, and RPB2 (second-largest subunit of the RNA polymerase II) loci across the genus Lactarius corroborates their morphology-based infrageneric placement. The discovery of this lineage changes our insights into the biogeography and evolutionary history of Lactarius subg. Plinthogalus.
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Agaricales , Basidiomycota , Fabaceae , Micorrizas , Humanos , Guiana , Filogenia , DNA Fúngico/genética , Agaricales/genética , Micorrizas/genética , Fabaceae/microbiologiaRESUMO
INTRODUCTION: The potential disruption in antiretroviral therapy (ART) services in Africa at the start of the COVID-19 pandemic raised concern for increased morbidity and mortality among people living with HIV (PLHIV). We describe HIV treatment trends before and during the pandemic and interventions implemented to mitigate COVID-19 impact among countries supported by the US Centers for Disease Control and Prevention (CDC) through the President's Emergency Plan for AIDS Relief (PEPFAR). METHODS: We analysed quantitative and qualitative data reported by 10,387 PEPFAR-CDC-supported ART sites in 19 African countries between October 2019 and March 2021. Trends in PLHIV on ART, new ART initiations and treatment interruptions were assessed. Viral load coverage (testing of eligible PLHIV) and viral suppression were calculated at select time points. Qualitative data were analysed to summarize facility- and community-based interventions implemented to mitigate COVID-19. RESULTS: The total number of PLHIV on ART increased quarterly from October 2019 (n = 7,540,592) to March 2021 (n = 8,513,572). The adult population (≥15 years) on ART increased by 14.0% (7,005,959-7,983,793), while the paediatric population (<15 years) on ART declined by 2.6% (333,178-324,441). However, the number of new ART initiations dropped between March 2020 and June 2020 by 23.4% for adults and 26.1% for children, with more rapid recovery in adults than children from September 2020 onwards. Viral load coverage increased slightly from April 2020 to March 2021 (75-78%) and viral load suppression increased from October 2019 to March 2021 (91-94%) among adults and children combined. The most reported interventions included multi-month dispensing (MMD) of ART, community service delivery expansion, and technology and virtual platforms use for client engagement and site-level monitoring. MMD of ≥3 months increased from 52% in October 2019 to 78% of PLHIV ≥ age 15 on ART in March 2021. CONCLUSIONS: With an overall increase in the number of people on ART, HIV programmes proved to be resilient, mitigating the impact of COVID-19. However, the decline in the number of children on ART warrants urgent investigation and interventions to prevent further losses experienced during the COVID-19 pandemic and future public health emergencies.
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COVID-19 , Infecções por HIV , Adulto , Criança , Humanos , Adolescente , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , COVID-19/prevenção & controle , Pandemias/prevenção & controle , Antirretrovirais/uso terapêutico , África/epidemiologiaRESUMO
BACKGROUND: The first COVID-19 case in the Democratic Republic of Congo (DRC) was reported on 10 March 2020 in Kinshasa, prompting the government to promote internationally agreed non-pharmacological interventions for infection prevention and control. Public compliance to these measures is critical and depends on the knowledge, attitudes, and practices (KAP) of communities regarding COVID-19, for which there was no data. This study aimed to bridge that gap. METHODS: A community-based cross-sectional study was conducted in Kinshasa in June 2020, during the emergency state, following a four-stage sampling process. Master's students from the Kinshasa School of Public Health conducted the survey. Descriptive and regression analyses were performed. RESULTS: The study enrolled 726 women and 600 men (mean age: 43; SD 16-85). Nearly everyone heard about COVID-19 (mainly through television, radio, and street reports), but only 17% were highly knowledgeable about its transmission modes, signs and symptoms, and preventive measures. More than 80% of participants believed in the disease's seriousness; however, only 21% found the total lockdown acceptable. Nonetheless, 86% reported regular hand cleaning and mask-wearing followed by physical distancing (72%). Poorer, younger, and non-Catholic participants were overall markedly less knowledgeable and had comparatively lower levels of health-protective attitudes, acceptance, and practices. The education level and household size did not matter. Female participants tended to show fewer enabling attitudes and practices toward COVID-19 prevention measures compared to men. CONCLUSION: Adequate public health information to improve the population's KAP related to COVID-19 is critical and must be designed with and delivered to the community-considering the specific needs of diverse sub-groups and contexts. Studies in Kinshasa and similar settings are necessary to understand the barriers to and enablers of acquiring, applying, and maintaining the optimal population's KAP for COVID-19 prevention and control.
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COVID-19 , Adulto , COVID-19/epidemiologia , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , Estudos Transversais , República Democrática do Congo/epidemiologia , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , MasculinoRESUMO
Sexual reproduction, mutation, and reassortment of nuclei increase genotypic diversity in rust fungi. Sexual reproduction is inherent to rust fungi, coupled with their coevolved plant hosts in native pathosystems. Rust fungi are hypothesised to exchange nuclei by somatic hybridisation with an outcome of increased genotypic diversity, independent of sexual reproduction. We provide criteria to demonstrate whether somatic exchange has occurred, including knowledge of parental haplotypes and rejection of fertilisation in normal rust life cycles.
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Basidiomycota , Doenças das Plantas , Animais , Basidiomycota/genética , Fungos , Estágios do Ciclo de Vida , Doenças das Plantas/microbiologia , ReproduçãoRESUMO
Polydiscidium is an enigmatic, monotypic, and rarely reported genus of Ascomycota of uncertain placement. The morphologically unique Polydiscidium martynii grows on dead wood and forms compound ascomata composed of thick, black, gelatinous somatic tissue that branches out from a common base. Multiple apothecia are located on the branches, mostly toward the tips, and are composed of 8-spored asci and paraphyses embedded in a gelatinous matrix that turns blue in Melzer's reagent. The species was previously known from only three collections from Guyana (holotype), Trinidad, and the Democratic Republic of the Congo and no sequences exist. Due to its peculiar morphology, taxonomic affinities of Polydiscidium have been debated, with different authors having placed it in Helotiaceae, Leotiaceae, or Leotiomycetes incertae sedis. Recent collections of this species resulting from long-term field work in Guyana and Cameroon led us to revisit the morphology and phylogenetic position of this fungus. Newly generated sequences of P. martynii were added to an Ascomycota-wide six-locus data set. The resulting phylogeny showed Polydiscidium to be a member of order Sclerococcales (Eurotiomycetes). Next, a four-locus (18S, ITS, 28S, mtSSU) phylogenetic reconstruction revealed that Polydiscidium is congeneric with Sclerococcum. A new combination is proposed for this species, Sclerococcum martynii. Micromorphological features, including the gelatinous hymenium composed of asci with amyloid gel cap and septate brown ascospores, are in agreement with Sclerococcum. New combinations are proposed for two additional species: Sclerococcum chiangraiensis and S. fusiformis. Finally, Dactylosporales is considered a later synonym of Sclerococcales.
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Ascomicetos , Ascomicetos/genética , Guiana , Filogenia , Esporos Fúngicos , Madeira/microbiologiaRESUMO
Rust fungi are important plant pathogens and have been extensively studied on crops and other host plants worldwide. This study describes the heterecious life cycle of a rust fungus on Digitaria eriantha (finger grass) and the Solanum species S. lichtensteinii (large yellow bitter apple), S. campylacanthum (bitter apple), and S. melongena (eggplant) in South Africa. Following field observations, inoculation studies involving telial isolates collected from Digitaria plants produced spermogonia and aecia on S. lichtensteinii, S. campylacanthum, and S. melongena. Likewise, inoculation of finger grass with aeciospores collected from the aforementioned Solanum species produced uredinia on D. eriantha. Pennisetum glaucum (pearl millet varieties Milkstar and Okashana, as well as 17 experimental lines) and S. elaeagnifolium (silverleaf nightshade or bitter apple) were resistant to the rust isolates. Morphological descriptions and molecular phylogenetic data confirmed the identity of the rust on Digitaria as P. digitariae, herein reinstated as a species and closely related to P. penicillariae the pearl millet rust, also reinstated. Puccinia digitariae has a macrocyclic, heterecious life cycle in which teliospores overwinter on dormant D. eriantha plants. Aecia sporulate on species of Solanum during spring and early summer to provide inocula that infect new growth of Digitaria.
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Basidiomycota , Solanum , Animais , Digitaria , Estágios do Ciclo de Vida , Filogenia , Doenças das Plantas/microbiologia , Plantas , Puccinia , África do SulRESUMO
Shifts in food microbiomes may impact the establishment of human pathogens, such as virulent lineages of Escherichia coli, and thus are important to investigate. Foods that are often consumed raw, such as lettuce, are particularly susceptible to such outbreaks. We have previously found that an undescribed Sporobolomyces yeast is an abundant component of the mycobiome of commercial romaine lettuce (Lactuca sativa). Here, we formally describe this species as Sporobolomyces lactucae sp. nov. (Pucciniomycotina, Microbotryomycetes, and Sporidiobolales). We isolated multiple strains of this yeast from commercial romaine lettuce purchased from supermarkets in Illinois and Indiana; additional isolates were obtained from various plant phylloplanes in California. S. lactucae is a red-pigmented species that is similar in appearance to other members of the genus Sporobolomyces. However, it can be differentiated by its ability to assimilate glucuronate and D-glucosamine. Gene genealogical concordance supports S. lactucae as a new species. The phylogenetic reconstruction of a four-locus dataset, comprising the internal transcribed spacer and large ribosomal subunit D1/D2 domain of the ribosomal RNA gene, translation elongation factor 1-α, and cytochrome B, places S. lactucae as a sister to the S. roseus clade. Sporobolomyces lactucae is one of the most common fungi in the lettuce microbiome.
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Hawaii has long been one of the last coffee-producing regions of the world free of coffee leaf rust (CLR) disease, which is caused by the biotrophic fungus Hemileia vastatrix. However, CLR was detected in coffee farms and feral coffee on the island of Maui in February 2020 and subsequently on other islands of the Hawaiian archipelago. The source of the outbreak in Hawaii is not known, and CLR could have entered Hawaii from more than 50 coffee-producing nations that harbor the pathogen. To determine the source(s) of the Hawaii inoculum, we analyzed a set of eleven simple sequence repeat markers (SSRs) generated from Hawaii isolates within a dataset of 434 CLR isolates collected from 17 countries spanning both old and new world populations, and then conducted a minimum spanning network (MSN) analysis to trace the most likely pathway that H. vastatrix could have taken to Hawaii. Forty-two multilocus genotypes (MLGs) of H. vastatrix were found in the global dataset, with all isolates from Hawaii assignable to MLG 10 or derived from it. MLG 10 is widespread in Central America and Jamaica, making this region the most probable source of inoculum for the outbreak in Hawaii. An examination of global weather patterns during the months preceding the introduction of CLR makes it unlikely that the pathogen was windborne to the islands. Likely scenarios for the introduction of CLR to Hawaii are the accidental introduction of spores or infected plant material by travelers or seasonal workers, or improperly fumigated coffee shipments originating from Central America or the Caribbean islands.
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Here, we report the draft genome sequence of Pseudotulostoma volvatum, an unusual ectomycorrhizal fungus in the "mold" order Eurotiales (Ascomycota, Pezizomycotina). The assembled genome is 60.4 Mbp and contains an estimated 5,492 genes. Compared with closely related species, the P. volvatum genome is depauperate in secondary metabolite gene clusters.