Filtrates from cultures of endophytic fungi isolated from leaves of Copaifera oblongifolia (Fabaceae) affect germination and seedling development differently / Fungos endofíticos isolados de folhas de Copaifera oblongifolia (Fabaceae) afetam diferentemente a germinação e o desenvolvimento das plântulas

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.

As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.

Diversity of fungi obtained from bats captured in urban forest fragments in Sinop, Mato Grosso, Brazil / Diversidade de fungos em morcegos de fragmentos florestais urbanos de Sinop, Mato Grosso, Brasil

Bats are important for the homeostasis of ecosystems and serve as hosts of various microorganisms including bacteria, viruses, and fungi with pathogenic potential. This study aimed to isolate fungi from biological samples obtained from bats captured in the city of Sinop (state of Mato Grosso, Brazil), where large areas of deforestation exist due to urbanization and agriculture. On the basis of the flow of people and domestic animals, 48 bats were captured in eleven urban forest fragments. The samples were processed and submitted to microbiological cultures, to isolate and to identify the fungal genera. Thirty-four (70.83%) of the captured bats were positive for fungi; 18 (37.5%) and 16 (33.33%) of these bats were female and male, respectively. Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp., and Candida sp., which may cause opportunistic infections, were isolated. The bat species with the highest number of fungal isolates was Molossus molossus: 21 isolates (43.8%). According to our results, bats captured in urban forest fragments in Sinop harbor pathogenic fungi, increasing the risk of opportunistic fungal infections in humans and domestic animals.

Os morcegos apresentam grande importância na homeostasia dos ecossistemas e são hospedeiros de uma rica diversidade de micro-organismos como bactérias, vírus e fungos com potencial patogênico. Portanto, este estudo visou isolar fungos presentes em amostras biológicas de morcegos na cidade de Sinop - MT, que possui grandes áreas de desmatamento devido à urbanização e agricultura. Foram capturados 48 morcegos de diferentes espécies, em onze fragmentos florestais urbanos definidos de acordo com fluxo de pessoas e animais domésticos, para obtenção de amostras biológicas. Essas amostras foram processadas e submetidas aos cultivos microbiológicos, para isolamento e identificação dos gêneros dos fungos. Dos 48 morcegos, 34 (70,83%) foram positivos para pelos menos um gênero de fungo, sendo 18 (37,5%) fêmeas e 16 (33,33%) machos, e os gêneros isolados a partir das amostras biológicas foram Penicillium sp., Scopulariopsis sp., Fusarium sp., Aspergillus sp., Alternaria sp., Cryptococcus sp., Trichosporon sp. e Candida sp., que podem ser causadores de infecções oportunistas. Desse total, a espécie que apresentou maior positividade para pelo menos um gênero de fungo foi Molossus molossus com 21 (43,8%). Nossos resultados demonstram que os morcegos capturados nos fragmentos florestais urbanos na cidade de Sinop - MT, podem atuar como agentes veiculadores de fungos com potencial patogênico, aumentando assim o risco de exposição e aquisição de infecções fúngicas oportunistas por pessoas e animais domésticos.

COVID-19-associated-mucormycosis: possible role of free iron uptake and immunosuppression.

COVID-19-associated-mucormycosis, commonly referred to as the "Black Fungus," is a rare secondary fungal infection in COVID-19 patients prompted by a group of mucor molds. Association of this rare fungal infection with SARS-CoV-2 infection has been declared as an endemic in India, with minor cases in several other countries around the globe. Although the fungal infection is not contagious like the viral infection, the causative fungal agent is omnipresent. Infection displays an overall mortality rate of around 50%, with many other secondary side effects posing a potential threat in exacerbating COVID-19 mortality rates. In this review, we have accessed the role of free iron availability in COVID-19 patients that might correlate to the pathogenesis of the causative fungal agent. Besides, we have analyzed the negative consequences of using immunosuppressive drugs in encouraging this opportunistic fungal infection.

Fungivory: a new and complex ecological function of Doru luteipes (Scudder) (Dermaptera: Forficulidae) / Fungivoria: uma nova e complexa função ecológica de Doru luteipes (Scudder) (Dermaptera: Forficulidae)

We report the discovery that the earwig predator Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) feed on Puccinia polysora Underw uredospore, the causal agent of Southern Rust of Corn (SRC), which is a primary disease affecting the maize crop in Brazil. We performed experiments in laboratory and greenhouse to test the effect of D. luteipes (1st/2nd and 3rd/4th instars, and adults) fungivory on the P. polysora uredospore concentration. All trials showed a significant reduction of the initial concentration of uredospore. There was a reduction in uredospore concentration with increase in number of D. luteipes feeding on them. We also tested the uredospore consumption by quantifying its percentage in the feces of D. luteipes. Nymphs of the 2nd, 4th instar and adults fed 88%, 85%, and 83.8% of the uredospore, respectively. For nymphs of the 3rd instar, the percentage of uredospore consumption (75.6%) was statistically significant compared with the other groups. In greenhouse experiment, at twenty-eight days after plant inoculation with 9.9 x 104 uredospores, the percentage of uredospore consumption was 81.7%. Our results confirmed the fungivory of D. luteipes on P. polysora uredospore. This is the first report of D. luteipes fungivory, which may play an important role in the biological control of P. polysora in corn.

Relatamos a descoberta de que o predador Doru luteipes (Scudder, 1876) (Dermaptera: Forficulidae) se alimenta de uredosporos de Puccinia polysora Underw, o agente causal da ferrugem polisora que é uma doença primária que afeta a cultura do milho no Brasil. Realizamos experimentos em laboratório e em casa de vegetação para testar o efeito da fungivoria de D. luteipes (1º/2º e 3º/4º iìstares e adultos) sobre a concentração de uredosporos de P. polysora. Todos os ensaios mostraram uma redução significativa da concentração inicial de uredosporos. Houve uma redução na concentração de uredosporos com o aumento do número de D. luteipes alimentando-se deles. Também testamos o consumo de uredosporos quantificando sua porcentagem nas fezes de D. luteipes. Ninfas do 2º e 4º ínstar, assim como adultos, alimentaram-se de 88%, 85% e 83,8% dos uredosporos, respectivamente. Para ninfas do 3º ínstar, a porcentagem de consumo de uredosporos (75,6%) foi estatisticamente significativo em comparação com os outros grupos. No experimento em casa de vegetação, aos 28 dias após a inoculação das plantas com 9,9 x 104 uredosporos, a porcentagem de consumo de uredosporos foi de 81,7%. Nossos resultados confirmaram a fungivoria de D. luteipes em uredosporos de P. polysora. Este é o primeiro relato de fungivoria de D. luteipes, que pode ter papel importante no controle biológico de P. polysora em milho.

Perception of fungi by farmers in the Cerrado / Percepção de agricultores do Cerrado sobre os fungos

Fungi are important in several aspects of human life. In particular, to agriculture, pathogenic fungi are of great importance, as they are responsible for production losses of the most diverse types. Because of this, knowledge about pathogenic fungus is of extreme importance for farmers and professionals working in agricultural areas. Among farmers who use specific agroecological practices, this knowledge is even more valuable, since by not adopting conventional methods of production, they resort to non-invasive alternatives that are less or not harmful at all to the environment in consideration of production management methods. This study aimed to assess farmer perception in the Cerrado biome in the city of Goiás (GO), Brazil, in order to understand their ethnomycological perceptions to verify historical management practices, their knowledge about phytopathogenic fungi, and how these producers perceive fungi. We used the theoretical reference method "From peasant to peasant" formulated by ANPA - National Association of Small Farmers. Some aspects of farmers' ethnomycological knowledge are discussed. These ease identification the representatives of the Fungi Kingdom is associated with organisms that present easily recognizable characteristics, such as wood-ears or disease-causing fungi. In general, farmers are able to identify representatives of the Fungi Kingdom that are found in their daily lives. The perception of farmers about fungi, a group still much unknown by society, is very relevant for future actions of ethnomycology.

Percepção dos fungos por agricultores do Cerrado – Fungos são organismos importantes em vários aspectos da vida humana. Em particular, para a agricultura, fungos patogênicos são de grande importância, pois são responsáveis por perdas de produção dos mais diversos tipos. Por isso, o conhecimento sobre fungos patogênicos é de extrema importância para agricultores e profissionais que trabalham em áreas agrícolas. Entre os agricultores que utilizam práticas agroecológicas, esse conhecimento é ainda mais valioso, pois, ao não adotar métodos convencionais de produção, recorrem a alternativas não invasivas que são menos ou não prejudiciais ao meio ambiente, considerando os métodos de gerenciamento da produção. Este estudo teve como objetivo avaliar a percepção de um grupo de agricultores do bioma Cerrado, na cidade de Goiás (GO), Brasil, a fim de compreender suas percepções etnomicológicas, de modo a verificar práticas históricas de manejo, seu conhecimento sobre fungos fitopatogênicos e como esses produtores percebem os fungos, de modo geral. Utilizamos o método "de camponês para camponês", formulado pela ANPA – Associação Nacional de Pequenos Agricultores. Discutimos alguns aspectos do conhecimento etnomicológico destes agricultores. A facilidade de identificação de representantes fúngicos está associada a organismos que apresentam características facilmente reconhecíveis, como estereótipo orelha-de-pau ou fungos causadores de doenças em cultivares. Em geral, os agricultores do estudo são capazes de identificar representantes do Reino Fungi que são encontrados em suas vidas cotidianas. A percepção dos agricultores sobre os fungos, um grupo ainda muito desconhecido pela sociedade, é muito relevante para ações futuras dentro da etnomicologia.

A comparative study on the virulence of entomopathogenic fungi against Trogoderma granarium (Everts) (Coleoptera: Dermestidae) in stored grains rice / Um estudo comparativo da virulência de fungos entomopatogênicos contra Trogoderma granarium (Everts) (Coleoptera: Dermestidae) em grãos armazenados de arroz

Entomopathogenic fungi (EPF) now a possible safer microbial control measure that could be considered as a substitute for chemical control of insect pests. Three EPF viz., Metarihizium anisopliae, Isaria furnosoroseus and Beauveria bassiana were evaluated for their virulence against the grubs of Khapra beetle, Trogoderma granarium (Everts) under laboratory conditions. The isolates were applied by two methods viz., diet incorporation and an immersion method with 3rd instar 20 grubs of T. granarium for each. The virulence of EPF was determined using percent mortality. Significantly higher mortality was observed in M. anisopliae applied through immersion (98.33%) and diet incorporation (93.33%) methods followed by B. bassiana (90.83 and 85.83%, respectively). The mortality caused by I. furnosoroseus was statistically lower in immersion and diet incorporation methods i.e. 81.67 and 73.33%, respectively. Based on the immersion method, all EPF were studied for multiple conidial concentration i.e., 1×104, 1×105, 1×106, 1×107 and 1×108 under the same in-vitro conditions. All the isolates were pathogenic to grub of T. granarium at the highest conidial concentration. M. anisopliae was proved the most effective virulent resulting in 98.33% mortality of the pest with LT50 4.61 days at 1 × 108 conidial concentration followed by 90.83 and 81.67 percent mortality with 5.07 and 8.01 days LT50, in the application of B. bassiana and I. furnosoroseus, respectively. M. anisopliae showed higher efficacy and could be considered as promising EPF for the development of myco-insecticides against effective biocontrol of T. granarium.

Os fungos entomopatogênicos (FPE) são agora a possível medida de controle microbiano mais segura, que pode ser considerada um substituto para o controle químico de pragas de insetos. Três EPF viz., Metarihizium anisopliae, Isaria furnosoroseus e Beauveria bassiana foram avaliados quanto à sua virulência contra as larvas do besouro Khapra, Trogoderma granarium (Everts) em condições de laboratório. Os isolados foram aplicados por dois métodos, a saber: incorporação de dieta e um método de imersão com 20 larvas de T. granarium de 3º ínstar para cada um. A virulência do EPF foi determinada usando a mortalidade percentual. Mortalidade significativamente maior foi observada em M. anisopliae aplicado pelos métodos de imersão (98,33%) e incorporação de dieta (93,33%), seguido por B. bassiana (90,83% e 85,83%, respectivamente). A mortalidade causada por I. furnosoroseus foi estatisticamente menor nos métodos de imersão e incorporação de dieta, ou seja, 81,67% e 73,33%, respectivamente. Com base no método de imersão, todos os EPFs foram estudados para múltiplas concentrações de conídios, ou seja, 1 × 104, 1 × 105, 1 × 106, 1 × 107 e 1 × 108 nas mesmas condições in vitro. Todos os isolados foram patogênicos à larva de T. granarium na maior concentração de conídios. M. anisopliae provou ser o virulento mais eficaz, resultando em 98,33% de mortalidade da praga com LT50 4,61 dias na concentração de 1 × 108 conídios seguido por 90,83% e 81,67% de mortalidade com 5,07 e 8,01 dias LT50, na aplicação de B. bassiana e I. furnosoroseus, respectivamente. M. anisopliae apresentou maior eficácia e pode ser considerada como um PFE promissor para o desenvolvimento de micoinseticidas contra o biocontrole efetivo de T. granarium.

Janus-Faced Molecules against Plant Pathogenic Fungi.

The high cytotoxicity of the secondary metabolites of mycotoxins is capable of killing microbes and tumour cells alike, similarly to the genotoxic effect characteristic of Janus-faced molecules. The "double-edged sword" effect of several cytotoxins is known, and these agents have, therefore, been utilized only reluctantly against fungal infections. In this review, consideration was given to (a) toxins that could be used against plant and human pathogens, (b) animal models that measure the effect of antifungal agents, (c) known antifungal agents that have been described and efficiently prevent the growth of fungal cells, and (d) the chemical interactions that are characteristic of antifungal agents. The utilization of apoptotic effects against tumour growth by agents that, at the same time, induce mutations may raise ethical issues. Nevertheless, it deserves consideration despite the mutagenic impact of Janus-faced molecules for those patients who suffer from plant pathogenic fungal infections and are older than their fertility age, in the same way that the short-term cytotoxicity of cancer treatment is favoured over the long-term mutagenic effect.

Mold in Foam Pillows and Mattresses: A Novel Cause of Hypersensitivity Pneumonitis.

Hypersensitivity pneumonitis (HP) is an inflammatory and/or fibrotic disease affecting the lung parenchyma and small airways. It typically results from an immune-mediated reaction provoked by an overt or occult inhaled antigen in susceptible individuals. The chronic or fibrotic form of HP has a poor prognosis, especially when no inciting antigen is identified, which occurs in up to 60% of cases. We report two cases of HP associated with exposure to mold in foam pillows and a mattress, which has not previously been reported as a risk factor for HP. Given the high prevalence of foam in pillows and mattresses, mold in foam in bedding may explain many HP cases with a previously unrecognized cause. Early identification and avoidance of foam in bedding may prevent HP progression to end-stage pulmonary fibrosis and death.

The taxonomy of two uncultivated fungal mammalian pathogens is revealed through phylogeny and population genetic analyses.

Ever since the uncultivated South American fungal pathogen Lacazia loboi was first described 90 years ago, its etiology and evolutionary traits have been at the center of endless controversies. This pathogen infects the skin of humans and as long believed, dolphin skin. However, recent DNA analyses of infected dolphins placed its DNA sequences within Paracoccidioides species. This came as a surprise and suggested the human and dolphin pathogens may be different species. In this study, population genetic analyses of DNA from four infected dolphins grouped this pathogen in a monophyletic cluster sister to P. americana and to the other Paracoccidioides species. Based on the results we have emended the taxonomy of the dolphin pathogen as Paracoccidioides cetii and P. loboi the one infecting human. Our data warn that phylogenetic analysis of available taxa without the inclusion of unusual members may provide incomplete information for the accurate classification of anomalous species.

Zearalenone and the Immune Response.

Zearalenone (ZEA) is an estrogenic fusariotoxin, being classified as a phytoestrogen, or as a mycoestrogen. ZEA and its metabolites are able to bind to estrogen receptors, 17ß-estradiol specific receptors, leading to reproductive disorders which include low fertility, abnormal fetal development, reduced litter size and modification at the level of reproductive hormones especially in female pigs. ZEA has also significant effects on immune response with immunostimulatory or immunosuppressive results. This review presents the effects of ZEA and its derivatives on all levels of the immune response such as innate immunity with its principal component inflammatory response as well as the acquired immunity with two components, humoral and cellular immune response. The mechanisms involved by ZEA in triggering its effects are addressed. The review cited more than 150 publications and discuss the results obtained from in vitro and in vivo experiments exploring the immunotoxicity produced by ZEA on different type of immune cells (phagocytes related to innate immunity and lymphocytes related to acquired immunity) as well as on immune organs. The review indicates that despite the increasing number of studies analyzing the mechanisms used by ZEA to modulate the immune response the available data are unsubstantial and needs further works.

Fungal natural products galaxy: Biochemistry and molecular genetics toward blockbuster drugs discovery.

Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules. This has been made possible because the isolation of metabolites from fungal natural sources is feasible and surpasses the organic synthesis of compounds, which otherwise remains a significant bottleneck in the drug discovery process. Here in this comprehensive review, we have discussed recent studies on different fungi (pathogenic, non-pathogenic, commensal, and endophytic/symbiotic) from different habitats (terrestrial and marines), the specialized metabolites they biosynthesize, and the drugs derived from these specialized metabolites. Moreover, we have unveiled the logic behind the biosynthesis of vital chemical scaffolds, such as NRPS, PKS, PKS-NRPS hybrid, RiPPS, terpenoids, indole alkaloids, and their genetic mechanisms. Besides, we have provided a glimpse of the concept behind mycotoxins, virulence factor, and host immune response based on fungal infections.

First record of gregarine protists (Apicomplexa: Sporozoa) in Asian fungus-growing termite Macrotermes barneyi (Blattaria: Termitidae).

Macrotermes barneyi, widely distributed in southern China, is the major fungus-growing termite in the subfamily Macrotermitinae. It has no flagellated protists in the guts. Here, we report occurrence of gregarine, a protozoan parasite in the digestive tract of M. barneyi. The general morphology and ultrastructure of the gregarine gamonts and syzygies by light micrograph and scanning electron micrograph are presented. SSU rDNA sequence analysis showed that the termite gregarine has the highest identity (90.10%) to that of Gregarina blattarum from cockroaches. Phylogenetic analysis based on the SSU rDNA sequences from diverse insect eugregarines indicated that the gregarine from M. barneyi is phylogenetically close to G. blattarus, L. erratica and G. tropica from Gregarinidae and Leidyanidae families, and may represent a novel species. This study expands our knowledge about the diversity of terrestrial eugregarines parasitizing in termites.

Presence of Incipient Fungal Infection in Atypical Squamous Lesions of the Lip.

ABSTRACT: Epidermal barrier disruption caused by atypical squamous proliferations of the lip (SOL) creates an ideal environment for fungal growth. Histologic features of SOL include parakeratosis overlying partial- or full-thickness keratinocyte atypia with or without invasion of the dermis, dermal solar elastosis, and scattered inflammatory cells which are predominantly lymphocytes. Histologic features of SOL with fungal superinfections overlap those seen in primary fungal cheilitis with reactive atypia, creating a diagnostic challenge. One-hundred seventy SOL cases were examined for the presence of fungal elements, and the histological features associated with superinfection were identified. Cases diagnosed as actinic cheilitis with fungal superinfection were carefully examined to rule out the possibility of misdiagnosed primary fungal cheilitis with reactive atypia. Histopathological characteristics commonly present with fungal hyphae included intraepidermal or intradermal neutrophils, bacterial colonies, and erosion or ulceration. Medical record review of those patients treated conservatively with topical antifungals revealed persistent clinical neoplasm and histological evidence of residual SOL on repeat biopsy. Thus, when biopsies exhibit histological overlap between these 2 entities, clinicians should keep a high index of suspicion for underlying SOL and carefully follow these patients if conservative antifungal therapy is initially trialed.

CRISPR-Cas9-Mediated Gene Silencing in Cultured Human Epithelia.

CRISPR/Cas9 technology enables rapid and efficient genome editing in a variety of experimental systems. Genome editing using CRISPR/Cas9 has become an increasingly popular genetic engineering tool due to (1) an extensive array of commercial ready-to-use CRIPSR/Cas9 systems, (2) improved efficiency of cell delivery, and (3) the possibility to do multigene editing. Here, we describe a method to introduce single gene disruption in lung bronchial epithelial cells. This approach can be used to study host factors important for pathogen interaction or to identify and study genetic markers determining susceptibility to fungal disease.

Measuring In Vivo Neutrophil Trafficking Responses During Fungal Infection Using Mixed Bone Marrow Chimeras.

Neutrophil migration to the site of infection is an essential process for the control and clearance of microbial growth within the host. Identifying the molecular factors that mediate neutrophil chemotaxis is therefore critical for our understanding of disease pathogenesis and the mechanisms underlying protective immunity. Here, we describe a protocol that enables analysis of neutrophil recruitment from the blood into fungal-infected organs in vivo, using mixed bone marrow chimeras and flow cytometry. This method directly assesses the relative contribution of a receptor or intracellular molecule in controlling neutrophil chemotaxis during fungal infection and can be adapted to a variety of other non-fungal infection experimental settings.

Murine Models of Hematopoietic Cell Transplantation to Investigate Fungal Infections.

Animal models are fundamental to unravel the complex nature of fungal infections in the host context. Here, a versatile murine model of hematopoietic cell transplantation (HCT) is described. This model can be used to investigate the establishment and progression of fungal infections after HCT and to elucidate how different transplant variables affect the recovery of host immunity.

Gut mycobiome: A promising target for colorectal cancer.

The human gut is mainly habited by a staggering amount and abundance of bacteria as well as fungi. Gut dysbiosis is believed as a pivotal factor in colorectal cancer (CRC) development. Lately increasing evidence from animal or clinical studies suggested that fungal disturbance also contributed to CRC development. This review summarized the current status of fungal dysbiosis in CRC and highlighted the potential tumorigenic mechanisms of fungi. Then the fungal markers and some therapeutic strategies for CRC were discussed. It would provide a better understanding of the correlation of mycobiota and CRC, and modulating fungal community would be a promising target against CRC.

ISSR markers to explore entomopathogenic fungi genetic diversity: Implications for biological control of tobacco pests.

Tobacco is one of the major industrial crops cultivated worldwide. Chemical control is the main method employed to reduce damage by insect pests. The use of entomopathogenic fungi represents an alternative to replace insecticides. The search for effective strains in the field constitutes a first step when developing a formulation. The objective of this work was to study genetic differences among isolates of entomopathogenic fungi obtained from tobacco grown soils using ISSR markers. The pathogenicity of the strains towards Helicoverpa gelotopoeon and Diabrotica speciosa was also assessed in order to search for a relationship between virulence and genetic diversity. Nineteen isolates were identified according to morphological features and molecular techniques as Beauveria bassiana (11) and Purpureocillium lilacinum (8). The diversity tree generated by ISSR analysis showed a high diversity among the strains. The pathogenicity towards H. gelotopoeon and D. speciosa was assessed and the logistic models generated showed that B. bassiana isolates LPSc1215 and LPSc1364 were the most pathogenic against both insect pests tested. In the diversity tree, these strains were grouped in a same cluster with a similarity level of approximately 85%, indicating a possible relationship between virulence and the band pattern generated.

Corynespora cassiicola in soybean seeds: incidence and transmission / Corynespora cassiicola em sementes de soja: incidência e transmissão

The fungus Corynespora cassiicola, the causal agent of the target spot in soybeans, has been considered, from the seed pathology point of view, a seed-borne pathogen of limited importance. Therefore, little importance has been given to the role of the seeds in the transmission of this pathogen. The objectives of this study were to determine the incidence of C. cassiicola in soybean seeds and evaluate the effects of this seed-borne pathogen, inoculated in the seeds, concerning to physiological and epidemiological parameters. The experiments were carried out at TAGRO and Embrapa Western Agriculture under lab (blotter test and seed germination test) and greenhouse conditions (growing on test). The fungus C. cassiicola was detected in 11.3% of the 639 seed samples analyzed, with an average incidence of 0.91% and a maximum of 8.5%. The transmission of C. cassiicola from the seeds to above-ground parts of soybean seedlings was demonstrated, by pathogen establishment on the cotyledon, showing circular lesions with concentric rings, reddish-brown in the center and surrounded by a yellowish-green halo, as a typical symptom of target spot. Reddish-brown lesions on the roots and stem of the seedlings were also observed. Considering a sample seed with 66.0% of C. cassiicola incidence, the symptomatic transmission based on cotyledon symptoms was 42.2%, corresponding to a transmission rate of 2.4:1. This is the first report, in a quantified way, about the transmission of C. cassiicola from the seeds to above-ground parts of soybean seedlings. When compared to non-inoculated seeds, seed germination, seedling emergence, and seedling initial development were influenced by the presence of the pathogen in the seeds, with the lowest values being observed when the seeds were inoculated.

O fungo Corynespora cassiicola, agente causal da mancha alvo da soja, tem sido considerado, do ponto de vista da patologia de sementes, um patógeno de importância limitada. Por esse motivo, pouca importância foi dada em relação ao papel das sementes na transmissão desse patógeno. Os objetivos desse trabalho foram determinar a incidência de C. cassiicola em sementes de soja bem como avaliar os efeitos da presença desse patógeno, inoculado nas sementes, com parâmetros fisiológicos e epidemiológicos. Os experimentos foram conduzidas na TAGRO e na Embrapa Agropecuária Oeste e constaram de testes de laboratório (blotter test e teste padrão de germinação) e de casa de vegetação (growing on test). O fungo C. cassiicola foi detectado em 11,3% das 639 amostras de sementes analisadas, com incidência média de 0,91% e a máxima de 8,5%. A transmissão de C. cassiicola, da semente para a parte aérea das plântulas de soja foi demonstrada, pelo estabelecimento do patógeno nos cotilédones, apresentando lesões circulares com anéis concêntricos, marrom-avermelhada no centro e com presença de halos amarelados, característicos da mancha alvo. Lesões radiculares e no colo das plântulas, de coloração marrom avermelhada, também foram observadas. Considerando a incidência de C. cassiicola na semente de 66,0%, a transmissão sintomática do fungo baseada em sintomas no cotilédone, foi de 42,2%, o que representou uma taxa de transmissão de 2,4:1. Esse é o primeiro relato, de forma quantificada, da transmissão de C. cassiicola das sementes para a parte aérea das plântulas de soja. Em comparação às sementes não inoculadas, a germinação das sementes, emergência e o desenvolvimento inicial das plântulas foram influenciados pela presença do patógeno nas sementes, com os menores valores sendo observados quando as sementes foram inoculadas.