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Lettuce is an economically major leafy vegetable that is affected by numerous diseases. One of the most devastating diseases of lettuce is white mold caused by Sclerotinia sclerotiorum. Control methods for this fungus are limited due to the development of genetic resistance to commonly used fungicides, the large number of hosts and the long-term survival of sclerotia in soil. To elaborate a new and more sustainable approach to contain this pathogen, 1,210 Pseudomonas strains previously isolated from agricultural soils in Canada were screened for their antagonistic activity against S. sclerotiorum. Nine Pseudomonas strains showed strong in vitro inhibition in dual-culture confrontational assays. Whole genome sequencing of these strains revealed their affiliation with four phylogenomic subgroups within the Pseudomonas fluorescens group, namely Pseudomonas corrugata, Pseudomonas asplenii, Pseudomonas mandelii, and Pseudomonas protegens. The antagonistic strains harbor several genes and gene clusters involved in the production of secondary metabolites, including mycin-type and peptin-type lipopeptides, and antibiotics such as brabantamide, which may be involved in the inhibitory activity observed against S. sclerotiorum. Three strains also demonstrated significant in planta biocontrol abilities against the pathogen when either inoculated on lettuce leaves or in the growing substrate of lettuce plants grown in pots. They however did not impact S. sclerotiorum populations in the rhizosphere, suggesting that they protect lettuce plants by altering the fitness and the virulence of the pathogen rather than by directly impeding its growth. These results mark a step forward in the development of biocontrol products against S. sclerotiorum. more...

Objetivo: compreender a vivência das puérperas na parturição no Centro de Parto Normal em um município do Agreste Paraibano. Método: trata-se de estudo descritivo, de abordagem qualitativa, realizado com puérperas, por meio de entrevista semiestruturada. A coleta de dados ocorreu nos meses de janeiro e fevereiro de 2020, em um Centro de Parto Normal. Os dados foram analisados conforme a técnica de análise de conteúdo temática. Resultados: dos dados empíricos emergiram as categorias: O cuidado da enfermeira obstétrica no contexto do Centro de Parto Normal; A presença do acompanhante durante o trabalho de parto. Constatou-se que as mulheres ficaram satisfeitas com o cuidado recebido pelas enfermeiras obstétricas. Foi evidenciado que a fisiologia, as escolhas e os sentimentos das mulheres foram respeitados durante o internamento. Conclusão: os cuidados ofertados proporcionaram vivências positivas, segurança e bem-estar no parto e pós-parto. Descritores: Centros de Assistência à Gravidez e ao Parto. Tocologia. Enfermagem Obstétrica. Parto Normal. Parto Humanizado. more...

Climate change is increasingly affecting agriculture through droughts, high salinity in soils, heatwaves, and floodings, which put intense pressure on crops. This results in yield losses, leading to food insecurity in the most affected regions. Multiple plant-beneficial bacteria belonging to the genus Pseudomonas have been shown to improve plant tolerance to these stresses. Various mechanisms are involved, including alteration of the plant ethylene levels, direct phytohormone production, emission of volatile organic compounds, reinforcement of the root apoplast barriers, and exopolysaccharide biosynthesis. In this review, we summarize the effects of climate change-induced stresses on plants and detail the mechanisms used by plant-beneficial Pseudomonas strains to alleviate them. Recommendations are made to promote targeted research on the stress-alleviating potential of these bacteria. more...

Lettuce is a major vegetable crop worldwide that is affected by numerous bacterial pathogens, including Xanthomonas hortorum pv. vitians, Pseudomonas cichorii, and Pectobacterium carotovorum. Control methods are scarce and not always effective. To develop new and sustainable approaches to contain these pathogens, we screened more than 1,200 plant-associated Pseudomonas strains retrieved from agricultural soils for their in vitro antagonistic capabilities against the three bacterial pathogens under study. Thirty-five Pseudomonas strains significantly inhibited some or all three pathogens. Their genomes were fully sequenced and annotated. These strains belong to the P. fluorescens and P. putida phylogenomic groups and are distributed in at least 27 species, including 15 validly described species. They harbor numerous genes and clusters of genes known to be involved in plant-bacteria interactions, microbial competition, and biocontrol. Strains in the P. putida group displayed on average better inhibition abilities than strains in the P. fluorescens group. They carry genes and biosynthetic clusters mostly absent in the latter strains that are involved in the production of secondary metabolites such as 7-hydroxytropolone, putisolvins, pyochelin, and xantholysin-like and pseudomonine-like compounds. The presence of genes involved in the biosynthesis of type VI secretion systems, tailocins, and hydrogen cyanide also positively correlated with the strains’ overall inhibition abilities observed against the three pathogens. These results show promise for the development of biocontrol products against lettuce bacterial pathogens, provide insights on some of the potential biocontrol mechanisms involved, and contribute to public Pseudomonas genome databases, including quality genome sequences on some poorly represented species. more...

Objetivo: conhecer os recursos familiares e as estratégias de enfrentamento utilizadas na situação de cuidar de uma criança com Síndrome Congênita do Zika vírus. Método: pesquisa qualitativa e interpretativa realizada com mulheres acometidas pelo Zika vírus na gestação e filhos com diagnóstico da Síndrome Congênita do Zika vírus, mediante análise temática de conteúdo embasada no modelo de resiliência, estresse, ajustamento e adaptação familiar. Coleta de dados realizada por meio de entrevistas semiestruturadas e construção de genogramas e ecomapas das famílias como suporte. Resultados: contribuíram como recursos para o enfrentamento das mulheres e famílias a própria família, amigos, vizinhos, grupos, pessoas da comunidade, profissionais de saúde, fontes de informação e a fé em Deus. Considerações finais: as estratégias utilizadas pelas mulheres e seus familiares para cuidar de criança com Síndrome Congênita do Zika vírus procuraram encontrar um caminho singular, em busca do equilíbrio no processo de adaptação, conforme cada realidade e necessidade. Descritores: Microcefalia. Zika vírus. Ajustamento Social. Saúde das Mulheres. Relações Familiares. more...

Air quality is of interest to many institutions and individuals, including, above all, the informed residents of monitored areas. The state of the air and its pollution level are very important to the health, life and functioning of any community living in urban areas. A poor state of the environment has inevitable health consequences; in the case of the air, these are mainly respiratory or cardiovascular diseases. This element intensifies during the heating season when compounds from the combustion of banned substances and materials are emitted into the atmosphere. The quality of the lowest layer of the atmosphere can be studied using various recording systems and detectors. These include continuous monitoring of the state of the air by spatially dispersed stationary measuring stations operating in the State Environmental Monitoring system. Their location is usually associated with significant traffic intensity in their immediate vicinity rather than high local residential density. The measurement network is also co-created and densified by alternative point air-qualitymonitoring systems proposed by private companies or community organizations (e.g., Airly, Sensor. Community, LoVo). A precious source of reliable local air quality data is mobile recording systems, which use unmanned aircraft or vehicles - objects in motion - and carry out periodic inspections, control missions or measurements. Examples of such solutions in the Polish market are Sniffer4D, Nosacz II and AirDrone. This paper aims to analyze and compare the available mobile measurement systems in terms of technical and usability for air quality research, along with a description of example areas where they are being used and implemented in practice. In addition, selected results of tests carried out with the Sniffer4D system at three testing grounds in Toruń are presented as part of a measurement campaign using an unmanned aerial vehicle and a passenger car. [ABSTRACT FROM AUTHOR] more...

Objective: to identify situations of vulnerability and accumulation of tensions in the care of the child with Congenital Zika Virus Syndrome. Methods: qualitative study, in which 40 mothers of children with Congenital Zika Virus Syndrome participated. The research instruments used were a semi-structured interview, construction of genograms and ecomaps and field diary notes. The collected data were submitted to content analysis in the thematic modality. Results: the main situations identified were caring alone for the child with Congenital Zika Virus Syndrome; conflicts with the partner or marital separation; family abandonment; absence or health problems with other children; and financial difficulties. Conclusion: vulnerabilities, family conflicts, and financial difficulties were considered sources of family tension and stress when facing expenses with medications and treatments, revealing racial and socioeconomic disparities in the access to health care. more...

Plant-beneficial phenazine-producing Pseudomonas

Rhizosphere colonization by phytobeneficial Pseudomonas spp. is pivotal in triggering their positive effects on plant health. Many Pseudomonas spp. Determinants, involved in rhizosphere colonization, have already been deciphered. However, few studies have explored the role played by specific plant genes in rhizosphere colonization by these bacteria. Using isogenic Arabidopsis thaliana mutants, we studied the effect of 20 distinct plant genes on rhizosphere colonization by two phenazine-producing P. chlororaphis strains of biocontrol interest, differing in their colonization abilities: DTR133, a strong rhizosphere colonizer and ToZa7, which displays lower rhizocompetence. The investigated plant mutations were related to root exudation, immunity, and root system architecture. Mutations in smb and shv3, both involved in root architecture, were shown to positively affect rhizosphere colonization by ToZa7, but not DTR133. While these strains were not promoting plant growth in wild-type plants, increased plant biomass was measured in inoculated plants lacking fez, wrky70, cbp60g, pft1 and rlp30, genes mostly involved in plant immunity. These results point to an interplay between plant genotype, plant growth and rhizosphere colonization by phytobeneficial Pseudomonas spp. Some of the studied genes could become targets for plant breeding programs to improve plant-beneficial Pseudomonas rhizocompetence and biocontrol efficiency in the field. more...

Type III secretion systems (T3SSs) are bacterial membrane-embedded nanomachines translocating effector proteins into the cytoplasm of eukaryotic cells. They have been intensively studied for their important roles in animal and plant bacterial diseases. Over the past two decades, genome sequencing has unveiled their ubiquitous distribution in many taxa of Gram-negative bacteria, including plant-beneficial ones. Here, we discuss the distribution and functions of the T3SS in two agronomically important bacterial groups: the symbiotic nodule-forming nitrogen-fixing rhizobia and the free-living plant-beneficial Pseudomonas spp. In legume-rhizobia symbiosis, T3SSs and their cognate effectors play important roles, including the modulation of the plant immune response and the initiation of the nodulation process in some cases. In plant-beneficial Pseudomonas spp., the roles of T3SSs are not fully understood, but pertain to plant immunity suppression, biocontrol against eukaryotic plant pathogens, mycorrhization facilitation, and possibly resistance against protist predation. The diversity of T3SSs in plant-beneficial bacteria points to their important roles in multifarious interkingdom interactions in the rhizosphere. We argue that the gap in research on T3SSs in plant-beneficial bacteria must be bridged to better understand bacteria/eukaryotes rhizosphere interactions and to support the development of efficient plant-growth promoting microbial inoculants. more...