Estudo do impacto no meio ambiente pelo processamento da farinha de mandioca no Município de São Felipe, Bahia.

O município de São Felipe localiza-se a uma latitude 12º50'50" sul e a uma longitude 39º05'22" oeste estando a uma altitude de 195 metros. Possui uma área de 198,71 km² uma população de aproximadamente 21.000 habitantes. Das atividades agrícolas destaca-se o cultivo da mandioca com técnicas ainda rudimentares. O Brasil é o segundo produtor de mandioca do mundo, sendo a planta resistente nas diferentes condições de cultivo, encontrada em todos os estados brasileiros. As utilizações culinárias caseiras da mandioca não acumulam resíduo significativo, pela pequena quantidade processada. Contudo, quando o processamento é maior, os subprodutos podem vir a apresentar problemas de disposição e soluções deverão ser encontradas. O processamento industrial da mandioca causa sérios problemas ambientais na disposição de resíduos, como poluição de rios, do solo, lençol freático e mortandade de peixes. Apesar dos agricultores serem familiarizados com a mandioca, desconhecem as variedades, os impactos que seus resíduos causam ao meio ambiente e o aproveitamento dos resíduos como uma fonte de sustentabilidade.PDF.035

Efeito da aplicação dos remineralizadores no solo.

Resumo - Os remineralizadores são insumos acessíveis aos agricultores. No Brasil, cerca de 5 milhões de hectares já receberam os remineralizadores, os quais têm apresentado resultados consistentes em campo. Os mecanismos de como funcionam os remineralizadores no solo ainda dependem de muito estudo, porém um conjunto de resultados de pesquisas permite conceber um modelo a ser testado. A integração de processos envolvidos inclui respostas das comunidades de microrganismos do solo à adição de minerais primários, quais sejam: crescimento radicular vigoroso das culturas, aumento do potencial de intemperismo de minerais, com consequente liberação de nutrientes, e formação de minerais secundários com superfícies ativas, resultando em agregados, fundamentais para a manutenção e para o aumento da matriz organomineral no solo. Solos tropicais pobres em minerais novos e nutrientes são mais responsivos, o que pode ser potencializado pela redução de pesticidas que comprometem a vida no solo e pelo uso de culturas de cobertura que colaboram para a diversidade e para o aporte de carbono. Os remineralizadores, pela ampla disponibilidade nas regiões agrícolas e pelos resultados agronômicos apresentados, devem ser tratados como recurso estratégico do Agro brasileiro

Princípios geoquímicos, mineralógicos e biológicos do manejo de remineralizadores de solos.

Resumo - Os remineralizadores de solos são insumos derivados de rochas silicáticas ricas em bases que passaram apenas por processos de cominuição, e que atendam aos critérios definidos por legislação do Ministério da Agricultura e Pecuária. Os conceitos da remineralização são derivados de processos naturais de renovação de solo por rochas moídas associados a geleiras, vulcões e planícies fluviais. Estes processos naturais permitem a transformação mineralógica acelerada das rochas naturalmente moídas por ação biológica das plantas, formando solos de elevada qualidade e com propriedades físicas, químicas e biológicas adequadas para o desenvolvimento das plantas selecionadas para a agricultura. Os efeitos diretos dos remineralizadores nos solos são: correção do pH, fornecimento de nutrientes e formação de novas fases minerais com elevada carga superficial. Estes efeitos diretos dependem da composição química, mineralógica e granulométrica dos remineralizadores. Classificam-se cinco tipos de fontes de rochas silicáticas para o desenvolvimento dos remineralizadores de solos: magnesiano (ultramáficas); cálcio-magnesiano-potássico (ultramáficas alcalinas); cálcio-magnesiano (básicas); cálcico (calcissilicáticas); potássico (alcalinas, ricas em biotita e em glauconita). O desenvolvimento da granulometria dos insumos derivados de rochas silicáticas utiliza os conceitos de reatividade dos minerais para a indicação dos efeitos de curto, médio e longo prazos em solos

Agricultura Sustentável Tropical: casos de sucesso.

Resumo - O Brasil passou de importador de grãos na década de 1970 para um dos maiores produtores mundiais de grãos nesta última década. Grandes áreas de campos nativos foram transformadas em terras agricultáveis e produtivas. Os avanços foram alcançados com base nos aprendizados trazidos por mestres oriundos dos países praticantes da agricultura temperada, e no entendimento de que o solo precisa ser corrigido com parâmetros físico-químicos bem definidos. Neste contexto de adequação da agricultura tropical, alguns produtores entenderam a necessidade de inovar, utilizando princípios observados na natureza para resolver problemas estru- turais de produção. Surgiu assim a agricultura de processos, cujo objetivo não é limitar-se ao tratamento curativo e sim criar condições favoráveis ao desenvolvimento da planta enquanto previne-se o desenvolvimento de doenças e pragas e melhora a resiliência desta aos desafios ambientais. Produtores pioneiros deste novo formato de se fazer agricultura, além de manterem níveis altos de produti- vidade em ambientes desafiadores, reduziram significativamente o custo de produção, permitindo aumentar a lucratividade por área trabalhada

Predicting the HMA-LMA status in marine sponges by machine learning

The dichotomy between high microbial abundance (HMA) and low microbial abundance (LMA) sponges has been observed in sponge-microbe symbiosis, although the extent of this pattern remains poorly unknown. We characterized the differences between the microbiomes of HMA (n=19) and LMA (n=17) sponges (575 specimens) present in the Sponge Microbiome Project. HMA sponges were associated with richer and more diverse microbiomes than LMA sponges, as indicated by the comparison of alpha diversity metrics. Microbial community structures differed between HMA and LMA sponges considering Operational Taxonomic Units (OTU) abundances and across microbial taxonomic levels, from phylum to species. The largest proportion of microbiome variation was explained by the host identity. Several phyla, classes, and OTUs were found differentially abundant in either group, which were considered “HMA indicators” and “LMA indicators”. Machine learning algorithms (classifiers) were trained to predict the HMA-LMA status of sponges. Among nine different classifiers, higher performances were achieved by Random Forest trained with phylum and class abundances. Random Forest with optimized parameters predicted the HMA-LMA status of additional 135 sponge species (1,232 specimens) without a priori knowledge. These sponges were grouped in four clusters, from which the largest two were composed of species consistently predicted as HMA (n=44) and LMA (n=74). In summary, our analyses shown distinct features of the microbial communities associated with HMA and LMA sponges. The prediction of the HMA-LMA status based on the microbiome profiles of sponges demonstrates the application of machine learning to explore patterns of host-associated microbial communities

Dynamics of Seed-Borne Rice Endophytes on Early Plant Growth Stages

Bacterial endophytes are ubiquitous to virtually all terrestrial plants. With the increasing appreciation of studies that unravel the mutualistic interactions between plant and microbes, we increasingly value the beneficial functions of endophytes that improve plant growth and development. However, still little is known on the source of established endophytes as well as on how plants select specific microbial communities to establish associations. Here, we used cultivation-dependent and -independent approaches to assess the endophytic bacterrial community of surface-sterilized rice seeds, encompassing two consecutive rice generations. We isolated members of nine bacterial genera. In particular, organisms affiliated with Stenotrophomonas maltophilia and Ochrobactrum spp. were isolated from both seed generations. PCR-based denaturing gradient gel electrophoresis (PCR-DGGE) of seed-extracted DNA revealed that approximately 45% of the bacterial community from the first seed generation was found in the second generation as well. In addition, we set up a greenhouse experiment to investigate abiotic and biotic factors influencing the endophytic bacterial community structure. PCR-DGGE profiles performed with DNA extracted from different plant parts showed that soil type is a major effector of the bacterial endophytes. Rice plants cultivated in neutral-pH soil favoured the growth of seed-borne Pseudomonas oryzihabitans and Rhizobium radiobacter, whereas Enterobacter-like and Dyella ginsengisoli were dominant in plants cultivated in low-pH soil. The seed-borne Stenotrophomonas maltophilia was the only conspicuous bacterial endophyte found in plants cultivated in both soils. Several members of the endophytic community originating from seeds were observed in the rhizosphere and surrounding soils. Their impact on the soil community is further discussed

Lifelong exposure to a low-dose of the glyphosate-based herbicide RoundUp® causes intestinal damage, gut dysbiosis, and behavioral changes in mice

RoundUp® (RUp) is a comercial formulation containing glyphosate (N-(phosphono-methyl) glycine), and is the world’s leading wide-spectrum herbicide used in agriculture. Supporters of the broad use of glyphosate-based herbicides (GBH) claim they are innocuous to humans, since the active compound acts on the inhibition of enzymes which are absent in human cells. However, the neurotoxic effects of GBH have already been shown in many animal models. Further, these formulations were shown to disrupt the microbiome of different species. Here, we investigated the effects of a lifelong exposure to low doses of the GBH-RUp on the gut environment, including morphological and microbiome changes. We also aimed to determine whether exposure to GBH-RUp could harm the developing brain and lead to behavioral changes in adult mice. To this end, animals were exposed to GBH-RUp in drinking water from pregnancy to adulthood. GBH-RUp-exposed mice had no changes in cognitive function, but developed impaired social behavior and increased repetitive behavior. GBH-Rup-exposed mice also showed an activation of phagocytic cells (Iba-1–positive) in the cortical brain tissue. GBH-RUp exposure caused increased mucus production and the infiltration of plama cells (CD138-positive), with a reduction in phagocytic cells. Long-term exposure to GBH-RUp also induced changes in intestinal integrity, as demonstrated by the altered expression of tight junction effector proteins (ZO-1 and ZO-2) and a change in the distribution of syndecan-1 proteoglycan. The herbicide also led to changes in the gut microbiome composition, which is also crucial for the establishment of the intestinal barrier. Altogether, our findings suggest that long-term GBH-RUp exposure leads to morphological and functional changes in the gut, which correlate with behavioral changes that are similar to those observed in patients with neurodevelopmental disorders

Endophytic bacterial community composition in wheat (Triticum aestivum) is determined by plant tissue type, developmental stage and soil nutrient availability

Aims: To understand effects of tissue type, growth stage and soil fertilisers on bacterial endophyte communities of winter wheat (Triticum aestivum cv. Hereward). Methods: Endophytes were isolated from wheat grown under six fertiliser conditions in the long term Broadbalk Experiment at Rothamsted Research, UK. Samples were taken in May and July from root and leaf tissues. Results: Root and leaf communities differed in abundance and composition of endophytes. Endophytes were most abundant in roots and the Proteobacteria were most prevalent. In contrast, Firmicutes and Actinobacteria, the Gram positive phyla, were most prevalent in the leaves. Both fertiliser treatment and sample time influenced abundance and relative proportions of each phylum and genus in the endosphere. A higher density of endophytes was found in the Nil input treatment plants. Conclusions: Robust isolation techniques and stringent controls are critical for accurate recovery of endophytes. The plant tissue type, plant growth stage, and soil fertiliser treatment all contribute to the composition of the endophytic bacterial community in wheat. These results should help facilitate targeted development of endophytes for beneficial applications in agriculture

Visualization of grapevine root colonization by the Saharan soil isolate Saccharothrix algeriensis NRRL B-24137 using DOPE-FISH microscopy

Background and aim There is currently a gap of knowledge regarding whether some beneficial bacteria isolated from desert soils can colonize epi- and endophytically plants of temperate regions. In this study, the early steps of the colonization process of one of these bacteria, Saccharothrix algeriensis NRRL B-24137, was studied on grapevine roots to determine if this beneficial strain can colonize a non-natural host plant. An improved method of fluorescence in situ hybridization (FISH), the double labeling of oligonucleotide probes (DOPE)-FISH technique was used to visualize the colonization behavior of such bacteria as well as to determine if the method could be used to track microbes on and inside plants. Methods A probe specific to Saccharothrix spp. was firstly designed. Visualization of the colonization behavior of S. algeriensis NRRL B-24137 on and inside roots of grapevine plants was then carried out with DOPE-FISH microscopy. Results The results showed that 10 days after inoculation, the strain could colonize the root hair zone, root elongation zone, as well as root emergence sites by establishing different forms of bacterial structures as revealed by the DOPE-FISH technique. Further observations showed that the strain could be also endophytic inside the endorhiza of grapevine plants. Conclusions Taking into account the natural niches of this beneficial strain, this study exemplifies that, in spite of its isolation from desert soil, the strain can establish populations as well as subpopulations on and inside grapevine plants and that the DOPE-FISH tool can allow to detect it