The microbiota associated with coffee plants may play a critical role in the final expression of coffee quality. However, the microbial diversity in coffee cherries is still poorly characterized. Here, we investigated the endophytic diversity in cherries of Coffea arabica by using culture-independent approaches to identify the associated microbes, ultimately to better understand their ecology and potential role in determining coffee quality. Group-specific 16S rRNA and 26S rRNA genes polymerase chain reaction - denaturing gradient gel electrophoresis and clone library sequencing showed that the endophytic community is composed of members of the 3 domains of life. Bacterial sequences showing high similarity with cultured and uncultured bacteria belonged to the Betaproteobacteria, Gammaproteobacteria, and Firmicutes phyla. Phylogenetic analyses of cloned sequences from Firmicutes revealed that most sequences fell into 3 major genera: Bacillus, Staphylococcus, and Paenibacillus. Archaeal sequences revealed the presence of operational taxonomic units belonging to Euryarchaeota and Crenarchaeota phyla. Sequences from endophytic yeast were not recovered, but various distinct sequences showing high identity with filamentous fungi were found. There was no obvious correlation between the microbial composition and cultivar or geographic location of the coffee plant. To the best of our knowledge, this is the first report demonstrating internal tissue colonization of plant fruits by members of the Archaea domain. The finding of archaeal small-subunit rRNA in coffee cherries, although not sufficient to indicate their role as active endophytes, certainly expands our perspectives toward considering members of this domain as potential endophytic microbes.

The relationships between plants and endophytic bacteria significantly contribute to plant health and yield. However, the microbial diversity in leaves of Eucalyptus spp. is still poorly characterized. Here, we investigated the endophytic diversity in leaves of hybrid Eucalyptus grandis x E. urophylla (Eucalyptus "urograndis") by using culture-independent and culture-dependent approaches, to better understand their ecology in leaves at different stages of Eucalyptus development, including bacteria with N2 fixation potential. Firmicutes, Proteobacteria (classes alpha-, beta- and gamma-) and Actinobacteria were identified in the Eucalyptus "urograndis" endophytic bacterial community. Within this community, the species Novosphingobium barchaimii, Rhizobium grahamii, Stenotrophomonas panacihumi, Paenibacillus terrigena, P. darwinianus and Terrabacter lapilli represent the first report these bacteria as endophytes. The diversity of the total endophytic bacteria was higher in the leaves from the 'field' (the Shannon-Wiener index, 2.99), followed by the indices obtained in the 'clonal garden' (2.78), the 'recently out from under shade (2.68), 'under shade' (2.63) and 'plants for dispatch' (2.51). In contrast, for diazotrophic bacteria, the highest means of these indices were obtained from the leaves of plants in the 'under shade' (2.56), 'recently out from under shade (2.52)' and 'field' stages (2.54). The distribution of the endophytic bacterial species in Eucalyptus was distinct and specific to the development stages under study, and many of the species had the potential for nitrogen fixation, raising the question of whether these bacteria could contribute to overall nitrogen metabolism of Eucalyptus.

Endophytic bacteria colonize the internal tissues of plants without causing infection or negative effects on their hosts. This study investigates the occurrence and diversity of culturable endophytic bacteria in the fruits of Coffea canephora at three developmental stages. Isolation and quantification were performed in R2A culture medium, and the diversity was established using molecular methods and analysis of fatty acid methyl esters (FAME). α-and γ-Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes were identified in the investigated community. Kocuria turfanensis and Pantoea vagans were identified as endophytes for the first time. Of the 18 species that were found, the following seven had not been previously described as endophytic in coffee fruits: Bacillus thuringiensis, Bacillus licheniformis, Agrobacterium tumefaciens, Escherichia coli, Enterobacter hormaechei, Chryseobacterium sp., and Ochrobactrum sp. The diversity of endophytic bacteria varied during the three developmental stages that were investigated, and the diversity was greatest in fruits during the green stage, during which Bacillus subtilis predominated. The number of Gram-positive bacteria was larger than the number of Gram-negative bacteria during the two earliest developmental stages, whereas their numbers were similar during the ripe stage. The diversity was lowest during the ripe stage, and Klebsiella oxytoca was the predominant species at this stage, probably due to the higher caffeine and sugar contents in the fruits.

Eucalyptus species are among the most widely grown and most economically valuable trees worldwide. In Brazil, eucalyptus is of major environmental and economic importance because it generates thousands of jobs and offers an alternative to using wood from native forests. In forest ecosystems, plant shoots are considered a common habitat for various microorganisms, and plants of the family Myrtaceae are an important source of fungal biodiversity. However, very little is known about the diversity and microbial distribution in eucalyptus leaves. This study aimed at showing the diversity and distribution of endophytic fungi in the leaves of eucalyptus plants aged 18 and 72 months. The leaves were collected at the onset of the rainy period, during the rainy period, and during the dry period. Diversity was measured using DNA extraction, 18S rRNA subunit amplifi cation, denaturing gradient gel electrophoresis (DGGE), and sequencing of eluted bands. The endophytic fungal community was affected by plant location. Differences observed in the distribution of the phylogenetic groups found in the upper, middle and lower thirds of the tree canopy indicate that the endophytic community distribution in eucalyptus is dependent on leaf position. The age of the plants affected the diversity of endophytic fungi in Eucalyptus "urograndis". Phylogenetic analysis showed that the phyla Basidiomycota and Ascomycota dominate in the environments studied. The description of endophytic fungal diversity in this important forest species is an important step for assessing this genetic resource in the search for metabolites and processes tha t can contribute to improving plant development.

Filter cake has been one of the most widely used waste products as a source of organic matter in the production of biofertilizers. However, sanitized sewage sludge is a recommended alternative for agricultural use because of environmental issues. Studies that examine the use of this particular class of fertilizer are needed. The objective of this work was to evaluate the efficiency of sewage sludge and filter cake as sources of organic matter in the composition of pelletized biofertilizers for soybean production. The experimental design was a randomized block design in a 2 x 4 + 2 factorial, which includes two sources of organic matter (sanitized sewage sludge and filter cake) and four levels of nitrogen (50, 75, 100, and 125%) relative to the recommended dose of phosphorus pentoxide compared with the mineral fertilizer. The use of organomineral fertilizer with the formulation of 75% sewage sludge showed greater growth for aerial plant parts. Biofertilizers formulated with sewage sludge and filter cake can replace mineral fertilizer and increase soybean growth. Quantitative changes in peroxidase, catalase and urease activity, as well as lipid peroxidation, were observed following the use of biofertilizers.

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Bactérias endofíticas residem nos tecidos internos das plantas em pelo menos uma etapa do seu ciclo de vida, sem causar sintomas aparentes de doença. São representadas por uma grande diversidade bacteriana composta pelos filos Alfa-, Beta-e Gamma-Proteobacteria, Actinobacteria, Firmicutes e Bacteroidetes. Em geral originam de comunidades bacterianas das raízes ou epifíticas, bem como sementes infectadas, podendo ainda, penetrar na planta ou ativamente ou por ferimentos e aberturas naturais. Após a penetração elas podem promover o crescimento vegetal pela produção de compostos promotores de crescimento, sendo ainda responsáveis pela liberação de metabólitos antimicrobianos, que podem suprimir patógenos. Apresentam potencial para utilização na agricultura e na indústria, podendo ser empregadas como vetores para introdução de genes de interesse em plantas, inibidores de patógenos e fontes de metabólitos primários e secundários de interesse. Assim, elas são importantes tanto na ciência básica como na aplicada, sendo de fundamental interesse o seu estudo. Portanto, buscou-se com este trabalho levantar os principais aspectos da interação planta-bactéria endofítica, enfatizando os processos de penetração, colonização e identificação delas na planta, baseando-se nas discussões atuais sobre o assunto.

Ocorrência de pombos (Columba livia) e excretas...