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1.
J Environ Manage ; 351: 119746, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38071918

RESUMEN

Land desertification poses a significant challenge in the Brazilian semiarid region, encompassing a substantial portion of the country. Within this region, the detrimental effects of human activities, particularly unsuitable anthropic actions, have resulted in diminished vegetation cover and an accelerated rate of soil erosion. Notably, practices such as overgrazing and the conversion of native forests into pasturelands have played a pivotal role in exacerbating the process of land desertification. Ultimately, land desertification results in significant losses of soil organic matter and microbial diversity. To address this pressing issue and contribute to the existing literature, various land restoration practices, such as grazing exclusion, cover crops, and terracing, have been implemented in the Brazilian semiarid. These practices have shown promising results in terms of enhancing soil fertility and restoring microbial properties. Nonetheless, their effectiveness in improving soil microbial properties in the Brazilian semiarid region remains a subject of ongoing study. Recent advances in molecular techniques have improved our understanding of microbial communities in lands undergoing desertification and restoration. In this review, we focus on assessing the effectiveness of these restoration practices in revitalizing soil microbial properties, with a particular emphasis on the soil microbiome and its functions. Through a critical assessment of the impact of these practices on soil microbial properties, our research aims to provide valuable insights that can help mitigate the adverse effects of desertification and promote sustainable development in this ecologically sensitive region.


Asunto(s)
Conservación de los Recursos Naturales , Suelo , Humanos , Microbiología del Suelo , Brasil , Bosques , China
2.
Chemosphere ; 328: 138581, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37019406

RESUMEN

Imazethapyr and flumioxazin are widely recommended herbicides for soybean fields due to their broad-spectrum effects. However, although both herbicides present low persistence, their potential impact on the community of plant growth-promoting bacteria (PGPB) is unclear. To address this gap, this study assessed the short-term effect of imazethapyr, flumioxazin, and their mixture on the PGPB community. Soil samples from soybean fields were treated with these herbicides and incubated for 60 days. We extracted soil DNA at 0, 15, 30, and 60 days and sequenced the 16S rRNA gene. In general, the herbicides presented temporary and short-term effects on PGPB. The relative abundance of Bradyrhizobium increased, while Sphingomonas decreased on the 30th day with the application of all herbicides. Both herbicides increased the potential function of nitrogen fixation at 15th days and decreased at 30th and 60th days of incubation. The proportions of generalists were similar (∼42%) comparing each herbicide and the control, while the proportion of specialists increased (varying from 24.9% to 27.6%) with the application of herbicides. Imazethapyr, flumioxazin and their mixture did not change the complexity and interactions of the PGPB network. In conclusion, this study showed that, in the short term, the application of imazethapyr, flumioxazin, and their mixture, at the recommended field rates, does not negatively affect the community of plant growth-promoting bacteria.


Asunto(s)
Herbicidas , Herbicidas/análisis , ARN Ribosómico 16S/genética , Suelo , Bacterias/genética , Glycine max
3.
Microb Ecol ; 85(3): 1072-1076, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35633375

RESUMEN

Soils from Brazilian semiarid regions are highly vulnerable to desertification due to their geology, climate, human actions, and intensive land use that contribute to desertification. Therefore, areas under desertification have increased in the Brazilian semiarid region and it has negatively changed the soil bacterial and archaeal communities and their functionality. On the other hand, although restoration strategies are expensive and there are few soils restoration programs, some practices have been applied to restore these soils under desertification. For instance, conservationist practices and grazing exclusion have been strategically implemented, and they created a new altered soil condition for soil microbial communities, boosting soil microbial diversity. Here, we discuss the potential of these restoration strategies to recover the richness and diversity of soil bacterial and archaeal communities that were described through environmental DNA (eDNA) sequencing of soil samples. eDNA sequencing results show that areas where restoration strategies have been applied in regions under desertification in the Brazilian semiarid have increased species richness, diversity, and structure of the bacterial and archaeal community. In addition, network connectivity and functionality of the soil microorganisms have been improved over time. Altogether, we show that management strategies for soil restoration have positive effects on soil microbial communities and these effects can be monitored using the eDNA sequencing approach.


Asunto(s)
Archaea , ADN Ambiental , Humanos , Archaea/genética , Suelo/química , Conservación de los Recursos Naturales , Brasil , Microbiología del Suelo , Bacterias/genética , ARN Ribosómico 16S/genética
4.
Chemosphere ; 313: 137417, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36460149

RESUMEN

Chromium (Cr) contamination can affect microorganisms in the soil, but the response of the microbial community in the rhizosphere of plants grown in Cr-contaminated soils is poorly understood. Therefore, this study assessed the microbial community, by amplicon sequencing, in the rhizosphere of maize and cowpea growing in uncontaminated (∼6.0 mg kg-1 Cr) and Cr-contaminated soils (∼250 mg kg-1 Cr). Comparing Cr-contaminated and uncontaminated soils, the microbial community in the maize rhizosphere clustered separately, while the microbial community in the cowpea rhizosphere did not present clear clustering. The microbial richness ranged from ∼5000 (rhizosphere in Cr-contaminated soil) to ∼8000 OTUs (in uncontaminated soil). In the comparison of specific bacterial groups in the rhizosphere of maize, Firmicutes were enriched in Cr-contaminated soil, including Bacilli, Bacillales, and Paenibacillus. Cowpea rhizosphere showed a higher abundance of six microbial groups in Cr-contaminated soil, highlighting Rhizobiales, Pedomicrobium, and Gemmatimonadetes. The microbial community in both rhizospheres presented a similar proportion of specialists comparing uncontaminated (2.2 and 3.4% in the rhizosphere of maize and cowpea, respectively) and Cr-contaminated soils (1.8 and 3.2% in the rhizosphere of maize and cowpea, respectively). This study showed that each plant species drove differently the microbial community in the rhizosphere, with an important effect of Cr-contamination on the microbial community assembly.


Asunto(s)
Microbiota , Contaminantes del Suelo , Vigna , Cromo/análisis , Rizosfera , Zea mays , Microbiología del Suelo , Bacterias , Suelo , Firmicutes , Contaminantes del Suelo/análisis
5.
Biosci. j. (Online) ; 39: e39095, 2023.
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1567440

RESUMEN

The current agricultural scenario faces diverse challenges, among which phytosanitary issues are crucial. Plant diseases are mostly treated with chemicals, which cause environmental pollution and pathogen resistance. In light of the UN Sustainable Development Goals (SDGs), the biochar alternative use to chemical inputs fits into at least six of the proposed goals (2, 3, 7, 13, 15, and 17), highlighting the 12th, which explains responsible consumption and production. Biochar is valuable for inducing systemic resistance in plants because it is a practical and frequently used resource for improving physical, chemical, and biological soil attributes. This review assessed the beneficial and potential effects of applying biochar to agricultural soils on bacterial pathogen management. Such application is a recent strategy; therefore, this research evaluated 20 studies that used biochar to manage plant diseases caused by pathogens inhabiting the soil in different systems. The effectiveness of biochar application in controlling plant diseases has been attributed to its alkaline pH, which contributes to the growth of beneficial microorganisms and increases nutrient availability, and its porous structure, which provides habitat and protection for soil microbiome development. Therefore, the combined effect of improvements on soil attributes through biochar application aids pathogen control. Biochar application helps manage plant diseases through different mechanisms, inducing plant resistance, increasing activities and abundance of beneficial microorganisms, and changing soil quality for nutrient availability and abiotic conditions.

6.
Arch Microbiol ; 204(12): 730, 2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36434407

RESUMEN

Bacteria have potential to tolerate and reduce metals. This study evaluated the potential of selected bacterial strains in tolerating and reducing chromium (Cr). Six bacterial strains (Rhizobium miluonense LCC01, LCC04, LCC05, and LCC69; Rhizobium pusense LCC43; and Agrobacterium deltaense LCC50) showed tolerance to Cr(VI) (16 and 32 µg mL-1), reduction potential of Cr(VI) (from 50 to 80%), and efficiency in producing exopolysaccharides. Rhizobium pusense LCC43 exhibited the highest tolerance (128 µg mL-1), reduction potential of Cr(VI) (from 80 to 100%), and efficiency in producing exopolysaccharides. These results suggested that this strain may have the potential to be used in the bioremediation of soils contaminated with Cr(VI).


Asunto(s)
Bacterias , Cromo , Oxidación-Reducción , Bacterias/genética
7.
Microbiol Res ; 264: 127161, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35987172

RESUMEN

Soil desertification has a significant social, economic, and environmental impact worldwide. Mycorrhizal diversity remains poorly understood in semiarid regions impacted by desertification, especially in Brazilian drylands. More importantly, positive impacts of grazing exclusion on mycorrhizal communities are still incipient. Here, we hypothesized that overgrazing changes the structure of Arbuscular Mycorrhizal Fungi (AMF) community compared to native areas and, grazing exclusion is effective to restore the AMF community. Thus, we analyzed the status of AMF community in soils under desertification (overgrazing) and restoration (twenty-years of grazing exclusion) in the Brazilian semiarid. AMF-spores were extracted via humid decantation methodology, morphologically classified, and alpha diversity metrics were calculated. Soil samples were chemically, and physically characterized and multivariate statistical analyses were applied to verify the impact of soil degradation and restoration on AMF-community. Briefly, native, and restored areas presented higher contents of organic matter, phosphorus, microbial carbon, and ß-glucosidase activity. However, degraded soil showed higher Al3+, Na+, and bulk soil density values. The abundance of AMF spores was higher in restored soil, followed by degraded and native vegetation, and Shannon's diversity index was significantly higher in restored soils, followed by native vegetation. AMF-spores were classified into four families (Gigasporaceae > Acaulosporaceae > Glomeraceae > Ambisporaceae). Ambisporaceae was closed correlated with degraded soil, mainly with Al3+, Na+, and bulk soil density properties. On the other hand, Acaulosporaceae and Glomeraceae were positively correlated with native vegetation and restored soil, respectively, thereby improving Shannon index, richness, enzyme activity, and soil respiration. Thus, grazing exclusion, in long term, can be a good strategy to restore AMF-diversity in soils in the Brazilian semiarid.


Asunto(s)
Glomeromycota , Micorrizas , Brasil , Conservación de los Recursos Naturales , Hongos , Humanos , Raíces de Plantas/microbiología , Suelo/química , Microbiología del Suelo , Esporas Fúngicas
8.
Data Brief ; 41: 107842, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35128002

RESUMEN

The data included in this article supplement the research article titled "Forest-to-pasture conversion modifies the soil bacterial community in Brazilian dry forest Caatinga (manuscript ID: STOTEN-D-21-19067R1)". This data article included the analysis of 18 chemical variables in 36 composite samples (included 4 replicates) of soils from the Microregion of Garanhuns (Northeast Brazil) and also partial 16S rRNA gene sequences from genomic DNA extracted from 27 of these samples (included 3 best quality replicates) for paired-end sequencing (up to 2 × 300 bp) in Illumina MiSeq platform (NCBI - BioProject accession: PRJNA753707). Soils were collected in August 2018 in a tropical subhumid region from the Brazilian Caatinga, along with 27 composite samples from the aboveground part of pastures to determine nutritional quality based on leaf N content. The analysis of variance (ANOVA) and post-hoc tests of environmental data and the main alpha-diversity indices based on linear mixed models (LMM) were represented in the tables. In this case, the collection region (C1 - Brejão, C2 - Garanhuns, and C3 - São João) was the random-effect variable and adjacent habitats formed by a forest (FO) and two pastures (PA and PB succeeded by this forest) composed the fixed-effect variable (land cover), both nested within C. In addition, a table with similarity percentages breakdown (SIMPER) was also shown, a procedure to assess the average percent contribution of individual phyla and bacterial classes. The figures showed the details of the study location, sampling procedure, vegetation status through the Normalized Difference Vegetation Index (NDVI), in addition to the general abundance and composition of the main bacterial phyla.

9.
Sci Total Environ ; 810: 151943, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34864020

RESUMEN

Soils comprise a huge fraction of the world's biodiversity, contributing to several crucial ecosystem functions. However, how the forest-to-pasture conversion impact soil bacterial diversity remains poorly understood, mainly in the Caatinga biome, the largest tropical dry forest of the world. Here, we hypothesized that forest-to-pasture conversion would shape the microbial community. Thus, the soil bacterial community was assessed using the 16S rRNA gene sequencing into the Illumina MiSeq platform. Then, we analyzed ecological patterns and correlated the bacterial community with environmental parameters in forest, and two distinct pastures areas, one less productive and another more productive. The variation in soil properties in pastures and forest influenced the structure and diversity of the bacterial community. Thus, the more productive pasture positively influenced the proportion of specialists and the co-occurrence network compared to the less productive pasture. Also, Proteobacteria, Acidobacteria, and Verrucomicrobia were abundant under forest, while Actinobacteria, Firmicutes, and Chloroflexi were abundant under pastures. Also, the more productive pasture presented a higher bacterial diversity, which is important since that a more stable and connected bacterial community could benefit the agricultural environment and enhance plant performance, as can be observed by the highest network complexity in this pasture. Together, our findings elucidate a significant shift in soil bacterial communities as a consequence of forest-to-pasture conversion and bring important information for the development of preservation strategies.


Asunto(s)
Microbiota , Suelo , Biodiversidad , Bosques , ARN Ribosómico 16S/genética , Microbiología del Suelo
10.
Int J Biol Macromol ; 161: 101-108, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32512096

RESUMEN

This study aimed to evaluate the production of fungal chitosan (FuChi) from Mucorales fungi cultivated in a cashew apple juice (CAJ) and cheese whey (CW) mixture, and to determine the growth-inhibitory effect of this biopolymer against Fusarium solani CFF109 and Scytalidium lignicola CMM1098, which cause root rot disease in cassava plants. Cunninghamella phaeospora UCP 1303 and Cunninghamella elegans UCP 1306 showed the highest FuChi production in screening assay, being selected to a CCRD 22 design to analyze the influence of different CAJ and CW concentrations in the increase of FuChi production. All nine Mucorales fungi cultivated in CAJ-CW medium, showing FuChi production in the range of 27.58 (Mucor hiemalis UCP 1309) to 65.40 mg/g (C. elegans UCP 1306). During CCRD 22 design, the highest FuChi production (64.09 mg/g) was achieved by C. elegans UCP 1306 cultivated in medium containing 40% (v/v) of CAJ and 30% (v/v) of CW, presenting 75% deacetylation degree and crystallinity indexes of 41.50%. FuChi at 16000 µg/mL showed a better inhibition against S. lignicola mycelial growth (81.70%) when compared with F. solani (22.13%) and induced alterations in hyphae morphology on both strains. CAJ and CW are promising substrates for FuChi production, and this biopolymer shows antimicrobial effect against F. solani and S. lignicola.


Asunto(s)
Antifúngicos/farmacología , Ascomicetos/efectos de los fármacos , Biotransformación , Quitosano/metabolismo , Fusarium/efectos de los fármacos , Residuos Industriales , Agricultura , Antifúngicos/química , Biomasa , Fenómenos Químicos , Quitosano/química , Hifa/efectos de los fármacos , Hifa/ultraestructura
11.
Braz. arch. biol. technol ; 62: e19180062, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1055405

RESUMEN

Abstract Protein hydrolysates originating from egg white have already been reported to be bioactive and, among their biological activities, possess the antioxidant property that protects the body from early ageing and diseases linked to oxidation. Therefore, the objective of this work was to evaluate the antioxidant activity of hydrolysates obtained by the hydrolysis of egg white from hen poultry. The protease produced by Aspergillus avenaceus URM 6706 was purified and subsequently applied to hydrolysate the egg white, and the degree of hydrolysis was verified during the protease exposure time (4-24 h). The hydrolysis was intensified over time of exposure to the protease. It was possible to detect the antioxidant activities of eliminating the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS•+) from 97% to 99% and 2,2-diphenyl-1-picrylhydrazyl (DPPH•) up to 27%, as well as the chelation of Cu2+ metal ions up to 62% and Fe2+ up to 54%. The elimination of ABTS•+ radical had a positive correlation with the degree of hydrolysis; however, all the other activities tested showed a negative correlation with the degree of hydrolysis. The results obtained suggest that the egg white of hen chicken represents a food source of animal origin with potential application in the functional food industry.


Asunto(s)
Aspergillus , Quelantes , Clara de Huevo , Péptido Hidrolasas , Antioxidantes
12.
Acta sci., Biol. sci ; 37(1): 71-79, jan.- mar. 2015. tab, ilus
Artículo en Inglés | LILACS | ID: biblio-847931

RESUMEN

The current study evaluated the proteases production from 11 fungal species belonging to the genera Mucor, Rhizomucor and Absidia. The species were obtained from the Collection of Cultures URM at the Mycology Department-UFPE, Brazil. The best producing species was Mucor hiemalis URM 3773 (1.689 U mL-1). Plackett-Burman design methodology was employed to select the most effective parameter for protease production out of 11 medium components, including: concentration of filtrate soybean, glucose, incubation period, yeast extract, tryptone, pH, aeration, rotation, NH4Cl, MgSO4 and K2HPO4. Filtrated soybean concentration was the significant variable over the response variable, which was the specific protease activity. The crude enzyme extract showed optimal activity in pH 7.5 and at 50ºC. The enzyme was stable within a wide pH range from 5.8 to 8.0, in the phosphate buffer 0.1M and in stable temperature variation of 40-70ºC, for 180 minutes. The ions FeSO4, NaCl, MnCl2, MgCl2 and KCl stimulated the protease activity, whereas ZnCl2 ion inhibited the activity in 2.27%. Iodoacetic acid at 1mM was the proteases inhibitor that presented greater action.The results indicate that the studied enzyme have great potential for industrial application.


Foi avaliada a produção de proteases por 11 espécies fúngicas pertencentes aos gêneros Mucor, Rhizomucor e Absidia, obtidas da Coleção de Culturas URM do Departamento de Micologia- UFPE, Brasil. A melhor espécie produtora foi Mucor hiemalis URM3773 (1,689 U mL-1). A metodologia de planejamento Plackett-Burman foi empregada para selecionar o parâmetro mais efetivo para a produção de proteases através de 11 componentes do meio, incluindo: concentração do filtrado de soja, glicose, período de incubação, extrato de levedura, triptona, pH, aeração, rotação, NH4Cl, MgSO4 e K2HPO4. A variável significante sobre a variável- resposta, atividade proteásica específica, foi a concentração do filtrado de soja. O extrato enzimático bruto apresentou atividade ótima ao pH 7,5 a 50ºC. A enzima foi estável em uma ampla variação de pH de 5,8­8,0 em tampão fosfato 0,1M e termicamente estável a uma variação de 40-70°C, durante 180 minutos. Os íons FeSO4, NaCl, MnCl2, MgCl2 e KCl estimularam a atividade proteásica, enquanto que o íon ZnCl 2 inibiu 2,27% da atividade. O inibidor de proteases que teve maior ação foi o ácido iodoacético a 1mM. Os resultados obtidos indicam que a enzima estudada tem grande potencial de aplicação industrial.


Asunto(s)
Péptido Hidrolasas
13.
ScientificWorldJournal ; 2014: 182025, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25506607

RESUMEN

Tannase is an enzyme that hydrolyzes esters and lateral bonds of tannins, such as tannic acid, releasing glucose and gallic acid and stands out in the clarification of wines and juices. Fungi of the genera Aspergillus and Penicillium are excellent producers of this enzyme. The search for fungi that produce high levels of tannase as well as new substrates for the enzyme production by the SSF is required. The objectives of this study were to evaluate the production of tannase by Aspergillus and Penicillium species through SSF using leaves and agroindustrial waste barbados cherry and mangaba fruit as substrate, select the best producer, optimize production, characterize the crude enzyme extract, and apply it the clarification of grape juice. Selecting the best producer was performed by planning Placket-Burman and RSM. P. montanense showed highest activity with 41.64 U/mL after 72 h of fermentation residue using barbados cherry, with 3.5% tannic acid and 70% moisture. The enzyme showed the highest activity at pH 9.0 and 50°C. The tannase of P. montanense was stable over a wide pH range and temperature and, when applied to grape juice, showed higher efficiency by reducing 46% of the tannin content after incubation 120 m.


Asunto(s)
Bebidas/microbiología , Metabolismo de los Hidratos de Carbono , Hidrolasas de Éster Carboxílico/biosíntesis , Fermentación , Residuos Industriales , Penicillium/enzimología , Vitis/química , Agricultura , Aspergillus/efectos de los fármacos , Aspergillus/metabolismo , Metabolismo de los Hidratos de Carbono/efectos de los fármacos , Estabilidad de Enzimas/efectos de los fármacos , Fermentación/efectos de los fármacos , Concentración de Iones de Hidrógeno , Penicillium/efectos de los fármacos , Especificidad de la Especie , Taninos/farmacología , Temperatura
14.
Biosci. j. (Online) ; 29(6): 1832-1839, nov./dec. 2013. graf, ilus
Artículo en Portugués | LILACS | ID: biblio-948365

RESUMEN

A mandioca é a sexta cultura de maior produção e expressão do planeta, estando atrás apenas de soja, trigo, arroz, milho e batata, sendo muito importante na alimentação humana, animal e na indústria. O Brasil é o segundo maior produtor mundial e esta cultura é a segunda de maior expressão econômica nacional. A Região Nordeste é uma das principais produtoras de mandioca no Brasil, estando vinculada a uma produção na qual utiliza pouca ou nenhuma tecnologia, o que vem contribuindo para o aumento da intensidade de doenças. A podridão radicular vem sendo relatada como uma das principais causas de perdas na produção. Por isso, o objetivo deste trabalho foi efetuar o primeiro levantamento de fungos associados à podridão radicular da mandioca em Pernambuco. Foram realizadas coletas de material vegetal com sintomas e/ou sinais da doença em quatro municípios que estão entre os principais produtores do estado: Jupi, Jucati, São João e Caetés. Foram selecionadas cindo propriedades em cada município e as coletas foram realizadas em cinco áreas com histórico da doença em cada propriedade. A frequência de isolamento dos fungos foi realizada pelo método de plaqueamento e isolamento até cultura pura para identificação. Os mais prevalentes foram submetidos a teste de patogenicidade em mandioca da cultivar branquinha. Foi encontrada alta diversidade de fungos associados à podridão radicular da mandioca no agreste de Pernambuco. Houve prevalência dos fungos Fusarium solani associados à podridão radicular em mandiocas com sintomas provenientes de todas as áreas dos municípios de Jupi, Jucati e São João e Scytalidium lignicola provenientes de áreas do Município de Caetés. Os isolados mais prevalentes Fusarium solani (CFF109) e Scytalidium lignicola (CFF408) apresentaram uma alta severidade em mandiocas da cultivar Branquinha.


Cassava is the sixth largest crop production and expression of the planet, being behind only soybeans, wheat, rice, corn and potatoes, is very important in human and animal feed and industry. The Brazil is the second largest producer in the world and this culture is the second highest expression of national economic.The Northeast region is one of the main cassava producers in Brazil, being the production use little or no technology, which has contributed to the increased intensity of diseases. The cassava root rot has been reported as a major cause of yield loss. Therefore, the objective of this study was to perform the first survey of fungi associated with cassava root rot in Pernambuco. Were collected plant materials with symptoms and / or signs of disease in four cities that are among the top producers in the Pernambuco state: Jupi, Jucati, São João and Caetés. We selected five properties in each municipality and the samples were collected in five areas with a history of disease in each property. The frequency of fungus isolation was performed by plating method, and isolation until pure culture for identification. The most prevalent were tested for pathogenicity in cassava cultivar branquinha. We found a high diversity of fungus associated with cassava root rot in Pernambuco. Fusarium solani was prevalence fungus associated with cassava root rot from all areas of Jupi, Jucati and


Asunto(s)
Manihot , Raíces de Plantas , Fusarium
15.
Biosci. j. (Online) ; 29(6): 1823-1831, nov./dec. 2013. graf, tab
Artículo en Portugués | LILACS | ID: biblio-948363

RESUMEN

A mandioca é de grande relevância para países do Sudeste da Ásia, África e América do Sul. Em Pernambuco as podridões vem induzindo a queda na produção e reduzindo as áreas de cultivo ao longo do tempo. O combate a essa doença ainda é um desafio, pois não existe fungicida registrado para o controle ou prevenção da doença e por ser causada por fitopatógenos habitantes do solo. Dentre a gama de fungos causadores de podridões está o Scytalidium lignicola, causador da podridão negra. Este trabalho teve como objetivo verificar o efeito de doses e fontes de matéria orgânica incorporados à solos arenosos com inoculação de Scytalidium lignicola sobre a podridão negra da mandioca cv. Pai Antônio. O experimento foi realizado com os materiais orgânicos, cama de aviário (CA) e esterco caprino (EC), incorporados ao solo arenoso nas concentrações (10, 20 e 30%) (v/v). As variáveis analisadas foram: severidade da doença, respiração basal do solo, carbono da biomassa microbiana das amostras, atributos químicos (pH, P, Na e K) e atributos bioquímicos fosfatase ácida e alcalina e urease. Os tratamentos com maiores poderes supressivos à podridão negra da mandioca foram EC 10 e 20% e CA 20 e 30%. A dose e o material orgânico que apresentou melhor desempenho sobre a supressividade da podridão negra da mandioca foi EC 10 e 20%.


Cassava is of great relevance to countries in Southeast Asia, Africa and South America In Pernambuco the rot comesin ducing drop in production and reducing the area under cultivate o nover time. Thefight against this disease remainsa challenge because there is no fungi cideregistered for the control or prevention of disease, is a disease caused by pathogen present in the soil. A mongthe range o ffungi that causerotis Scytalidium lignicola causes black rot. Thisstudy aimed to verify the effectof doses and sources of organic matterin corporated into sandy soil sinoculated with Scytalidium lignicola on the black rotof cassava cv.Father Antonio. The experimentwas conducted withorganic materials, litter (CA) andgoat manure(EC) incorporated into thesandy soilconcentrations(10, 20 and 30%) (v / v). The variables analyzed were: disease severity, soil basal respiration, microbial biomass carbonsamples, the chemical (pH, P, Na andK) and biochemical attribute sand alkaline phosphatase and urease. The suppressive treatments with greater powers to black rotof cassava were EC 10and 20%and CA20 and 30%. The dose and organic material that performed bettering the suppressiveness of cassava black root, caused by Scytalidium lignicola was EC 10 and 20%.


Asunto(s)
Manihot , Materia Orgánica , Estiércol , Suelo , Hongos
16.
Ciênc. agrotec., (Impr.) ; 34(1): 68-73, jan.-fev. 2010. tab, ilus
Artículo en Portugués | LILACS | ID: lil-541457

RESUMEN

Conduziu-se este trabalho, com o objetivo de avaliar a utilização de esterco caprino na composição de substratos para a formação de mudas de mamoeiro. O delineamento experimental adotado foi o de blocos casualizados com cinco tratamentos e quatro repetições, sendo cada parcela constituída por oito plantas. Os tratamentos constaram de misturas composta por: 100 por cento plantmax; 50 por cento terra, 25 por cento plantmax, 25 por cento de esterco bovino; 50 por cento terra, 25 por cento plantmax, 25 por cento esterco caprino; 30 por cento terra, 35 por cento plantmax, 35 por cento esterco bovino; 30 por cento terra, 35 por cento plantmax, 35 por cento esterco caprino. As variáveis analisadas foram: altura de planta; diâmetro do colo; número de folhas, comprimento de raiz; matéria seca da parte aérea e matéria seca da raiz. Os dados demonstram que a mistura mais eficiente para a formação de mudas de mamoeiro foi de 30 por cento terra, 35 por cento Plantmax, 35 por cento esterco caprino.


The objective of this work was to evaluate the utilization of goat manure in the substrate composition of papaya seedling formation. The experimental design used was of complete randomized blocks, with five treatments and four replications, and having eight plants per plot. The treatments consisted of substrate mixtures composed of: 100 percent Plantmax; 50 percent soil, 25 percent Plantmax, and 25 percent cattle manure; 50 percent soil, 25 percent Plantmax, and 25 percent goat manure; 30 percent soil, 35 percent Plantmax, and 35 percent cattle manure; 30 percent soil, 35 percent Plantmax, and 35 percent goat manure. Plant height and diameter, number of leaves per plant, root length, and shoot and root dry mass were evaluated. Substrate composed of 30 percent soil, 35 percent Plantmax, and 35 percent goat manure was most efficient for promoting growth.

17.
Ciênc. agrotec., (Impr.) ; 32(5): 1387-1393, set.-out. 2008. ilus
Artículo en Portugués | LILACS | ID: lil-496981

RESUMEN

Objetivou-se, neste trabalho, avaliar in vitro a atividade dos extratos alcoólicos de Senna alata (L.) Roxb. sobre Monosporascus cannonballus. O delineamento experimental foi inteiramente casualizado com esquema fatorial 3 x 6 + 1, sendo constituído por três partes da planta (caule, raiz e vagem), por seis concentrações (0,25; 0,50; 50; 75; 250; 500 ppm ) mais a testemunha, com quatro repetições por tratamento. As variáveis avaliadas foram: taxa de crescimento micelial (TCM), inibição do crescimento micelial (ICM) e área abaixo da curva do crescimento micelial (AACCM). A concentração de 500 ppm foi a mais eficiente, nas três partes vegetais avaliadas. O porcentual de inibição na referida concentração foi de 28,60 por cento, 36,70 por cento e 27,99 por cento para caule, raiz e vagem respectivamente. Diante dos resultados, observa-se que os extratos de S. alata indicam um forte potencial de controle para o fungo Monosporascus cannonballus.


The aim of this work was to evaluate the activity in vitro of the ethanolic extracts of Senna alata (L.) Roxb. over Monosporascus cannonballus. The experimental design was entirely randomized with factorial scheme 3 x 7 + 1, being constituted by three parts of the plant (root, stalk and green bean) for six different concentrations (0.25; 0.50, 50, 75, 250,500 ppm) plus the control, with four repeatitons for treatment. The available variables were: rate of micelial growth (TCM), inhibition of the growth micelial (ICM) and area under the curve of the growth micelial (AACCM). The concentration of 500 ppm was the most efficient ,in the three available vegetal parts. The percentual of inhibition in the concentration was of 28.60 percent, 36.70 percent e 27.99 percent for stalk, root and green bean respectively. Before of the results, the extracts of S. alata display high control potential for Monosporascus cannonballus fungi.

18.
Ciênc. agrotec., (Impr.) ; 32(3): 797-803, maio-jun. 2008. graf
Artículo en Portugués | LILACS | ID: lil-487946

RESUMEN

O fungo Monosporascus cannonballus é um importante patógeno radicular que ocasiona a síndrome denominada colapso em cucurbitáceas. No presente trabalho, objetivou-se, avaliar os efeitos da cobertura de planta com agrotêxtil branco de 15 g m-2, sobre a densidade populacional de M. cannonballus, em solo cultivado com melancia [Citrullus lanatus (Thumb.) Matsu & Nakai]. O delineamento experimental utilizado foi o de blocos casualizados em esquema de parcelas subdivididas, com três repetições. As parcelas foram constituídas por utilização ou não do agrotêxtil e as subparcelas pelas épocas de coleta de solo (0, 12, 24, 36, 48 dias após o transplantio). As variáveis analisadas foram densidade de ascósporos, temperatura do solo e do ar. Não houve influência da utilização da cobertura de agrotêxtil perante a densidade de ascósporos de M. cannonballus, no solo cultivado com melancia, mesmo que tenha proporcionado redução nas temperaturas médias do ar e do solo, sendo uma alternativa eficaz de manejo, na produção da melancia Mickylee.


The fungus M. cannonballus is an important root pathogen that causes collapse in cucurbitaceas. The present work had as objective to evaluate the effect of the row cover with white polypropylene of 15 g m-2 on the population density of M.cannonballus in soil cultivated with watermelon [Citrullus lanatus (Thumb.) Matsu & Nakai]. The experimental design was of randomized blocks using parcels subdivided scheme with three replications. The parcels consisted of use or not row cover and subparcelas through the time of soil collected (0, 12, 24, 36, 48 days after the transplanting). The variables evaluates were ascospores density, soil temperature and air temperature. There was not influence of the characteristics gotten for the row cover before the ascospores density of M. cannonballus, in the soils cultivated with watermelon and proportioning reduction of soil temperature means and air temperature means, being efficient alternative in the Mickylee watermelon production.

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