Guarana propagation strategies: a review.

Guarana [Paullinia cupana var. sorbilis (Mart.) Ducke] is a species of great economic and social important in Brazil, as it is the only commercial guarana producer in the world. The vegetative propagation method indicated for the culture is stem cuttings, which aims at productivity, tolerance, and uniformity of clonal cultivars, because reproduction by seeds has slow germination and high genetic variability, which in traditional varieties is an undesirable factor. Genetic factors can interfere with the rooting capacity of the crop. Studies seek alternatives that can improve this condition and enhance the production system. Use of growth regulators, microorganisms that promote plant growth, variation of substrates and fertilization, have been strategies used. Preliminary tests on the rate of stem rooting and seed germination with the use of exogenous phytohormone did not demonstrate in relation to the non-application of these inducers. The use of rhizobacteria, which presents itself as a promising activity in many cultures, has not yet been demonstrated in the culture of guarana. On the other hand, the influence of different substrates on rooting has already shown consistent results as a function of rooting rate. Fertilizing the mother plants as recommended by the production system for the crop has proven to be an efficient procedure. There are still few studies aimed at improving the spread of guarana, demonstrating that new protocols need to be explored, or that the protocols already used are reviewed from another perspective.

Mycoviruses infecting Colletotrichum spp: a comprehensive review / Micoviroses em Colletotrichum spp: uma revisão abrangente

Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.

Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.

Mycoviruses infecting Colletotrichum spp.: A comprehensive review

Abstract Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.

Resumo Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.

Mycoviruses infecting Colletotrichum spp: A comprehensive review / Micoviroses em Colletotrichum spp: uma revisão abrangente

Abstract Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.

Resumo Colletotrichum é um dos gêneros fúngicos mais importantes economicamente, afetando uma ampla gama de hospedeiros, especialmente em cultivos tropicais e subtropicais. Atualmente já existem diversos registros de infecção por micovírus em Colletotrichum spp., sendo a maioria dos já identificados classificados na família Partitiviridae. Ocorrem registros também de micovírus pertencentes à família Chrysoviridae. Compreendem vírus de genoma de (+)ssRNA e dsRNA que podem ser ou não envelopados. Ainda não foram identificados micovírus com genoma de DNA isolados de Colletotrichum. A infecção por micovírus pode ocorrer de forma latente, mas já foi observado em Colletotrichum spp. o fenômeno de hipo e hipervirulência. Além de influenciar no comportamento patogênico, a infecção pode causar mudanças fisiológicas importantes como alterações das características morfológicas, redução do crescimento vegetativo e redução na produção de conídios. O estudo com micovírus em fungos fitopatogênicos traz uma alternativa ao controle químico que é um método capaz de causar danos irreversíveis ao homem e o meio ambiente. Sob a perspectiva agrícola, os micovírus podem contribuir para agricultura sustentável como agentes de controle biológico. Isso porque obsevam-se mudanças importantes na fisiologia fúngica resultando na perda total ou redução da virulência desses patógenos.

Mycoviruses infecting Colletotrichum spp.: A comprehensive review.

Colletotrichum is one of the most economically important fungal genera, which affects a wide range of hosts, specifically tropical and subtropical crops. Thus far, there have been several records of mycovirus infection in Colletotrichum spp., primarily by viruses of the Partitiviridae family. There have also been records of infections by mycoviruses of the Chrysoviridae family. Mycoviruses are (+)ssRNA and dsRNA genome viruses, which may or may not be enveloped. To date, no mycovirus with a DNA genome has been isolated from Colletotrichum spp. Typically, mycoviruses cause latent infections, although hypo- and hypervirulence have also been reported in Colletotrichum spp. In addition to its effects on pathogenic behavior, mycovirus infection can lead to important physiological changes, such as altered morphological characteristics, reduced vegetative growth, and suppressed conidia production. Therefore, research on mycoviruses infecting phytopathogenic fungi can help develop alternative methods to chemical control, which can cause irreversible damage to humans and the environment. From an agricultural perspective, mycoviruses can contribute to sustainable agriculture as biological control agents via changes in fungal physiology, ultimately resulting in the total loss of or reduction in the virulence of these pathogens.

Cr (VI) reduction by photocatalyic process: Nb2O5 an alternative catalyst.

In this study, Nb2O5 catalyst was applied in the photocatalytic process for the Chromium reduction. Cr (VI) is a compound classified as highly toxic and often found in industrial tannery effluents. The techniques used for the photocatalytic material characterization were: X-ray diffraction, Specific surface area (B.E.T method), photo-acoustic spectroscopy, Scanning Electron Microscopy (SEM) and X-ray Dispersive Energy Spectrometry (EDS). A comparison between Nb2O5 and TiO2 (widely used in photocatalytic reactions) indicated that Nb2O5 has 20% more Cr (VI) reduction than TiO2. Tests carried out with Nb2O5 calcined at 500 °C and with non-calcined Nb2O5 showed that the heat treatment did not favor the reaction. Parameters such as pH, radiation intensity, initial concentration of Cr (VI) and amount of catalyst were studied. The results indicated that the acid (pH 2), emitted radiation intensity (250 W), initial concentration Cr (VI) at 10 mg L-1 and 1.5 g L-1 Nb2O5 non-calcined are the process optimal conditions. In addition, the reuse tests for Nb2O5 in consecutive cycles four, were realized. Photostability was maintained at approximately 90% for all cycles when Nb2O5 calcined was used. On the other hand, when using Nb2O5 non-calcined reduced by 21% during the four tests. This behavior is possibly due to the greater adsorption capacity of the non-calcined material. Making the Nb2O5 catalyst attractive for considering larger scale tests.

Cytomegalovirus seroepidemiology in an urban community of São Paulo, Brazil.

INTRODUCTION: After the era of rubella vaccine, cytomegalovirus (CMV) infection is one of the most frequently causes of mental retardation and congenital deafness. Seroepidemiological studies are necessary to understand the transmission dynamics of the disease. The purpose of the study was to quantify the transmission rate of CMV disease in a community in the state of São Paulo, Brazil. METHODS: Using ELISA test (IgG), a retrospective serological survey looking for CMV antibodies was performed in an non-immunized community. Frozen sera from 443 individuals, randomly selected by cluster sampling technique in the town of Caieiras, São Paulo, were collected from November 1990 to January 1991. Seroprevalence was stratified by age (0-40 years). Mathematical techniques were applied to determine the age-dependent decay function of maternal antibodies during the first year of life, the age-dependent seroprevalence function and the force of infection for CMV in this community. RESULTS: It was observed a descending phase of seropositivity in the first 9 months, but changes in antibody titration were observed between 8 months old and one year of age. The average age of the first infection was 5.02 months of age and 19.84 years, when the age-dependent seroprevalence and the force of infection were analyzed between 10 months of age and 10 years of age and from 10 to 40 years old, respectively. CONCLUSION: CMV infection is highly prevalent among the population studied and infection occurs in the first year of life. This study shows that most women at reproductive age are vulnerable to the first infection, increasing the risk for congenital infection.

Cytomegalovirus seroepidemiology in an urban community of Säo Paulo, Brazil

Introdução: Após a era da vacinação contra a rubéola, a citomegalovirose tornou-se uma das causas mais freqüentes de surdez congênita e retardamento mental. Estudos soroepidemiológicos são necessários para entender a dinâmica de transmissão da doença. O objetivo do estudo foi quantificar a transmissão dessa doença em comunidade do Estado de São Paulo, Brasil. Métodos: Foi realizado estudo sorológico retrospectivo utilizando anticorpos contra o citomegalovírus (CMV) de classe IgG, pelo método ELISA, em soros congelados de 443 indivíduos, randomizados e selecionados pela técnica de Cluster, provenientes da comunidade de Caieiras, uma pequena cidade localizada nos arredores de São Paulo. As amostras foram colhidas entre novembro de 1990 e janeiro de 1991. No estudo da soroprevalência estratificada por idade (0 a 40 anos), foram aplicadas técnicas matématicas para a determinação da função de decaimento de anticorpos maternos durante o primeiro ano de vida, da função de soroprevalência por idade e da força de infecção para o CMV na comunidade. Resultados: Foi observada uma fase descendente da soropositividade durante os primeiros nove meses, porém ocorreram mudanças nos títulos de anticorpos entre oito meses e um ano de vida. A idade média de aquisição da primeira infecção foi de 5,02 meses e 18,84 anos, quando se analisaram a soroprevalência e a força de infecção, idade dependentes, respectivamente entre 10 meses e 10 anos e 10 e 40 anos. Conclusões: A citomegalovirose é altamente prevalente na população estudada e ocorre precocemente já no primeiro ano de vida. O estudo demonstrou que mulheres em idade reprodutiva se encontravam vulneráveis à primeira infecção, aumentando a chance de doença congênita