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1.
J Environ Qual ; 52(5): 1024-1036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37533339

RESUMO

Vineyard soils can be contaminated by copper (Cu) due to successive applications of fungicides and organic fertilizers. Soil remediation can be addressed by altering soil properties or selecting efficient Cu-extracting cover crops tolerant to Cu toxicity. Our objectives were to synthesize the Cu-extracting efficiency by plant species tested in Brazil, classify them according to Cu resistance to toxicity, and assess the effect of soil properties on attenuating Cu toxicity. We retrieved results from 41 species and cultivars, totaling 565 observations. Freshly added Cu varied between 50 and 600 mg Cu kg-1 of soil across studies. The partition of Cu removal between the above- and below-ground portions was scaled as a logistic variable to facilitate data synthesis. The data were analyzed using the Adaboost machine learning model. Model accuracy (predicted vs. actual values) reached R2  = 0.862 after relating species, cultivar, Cu addition, clay, SOM, pH, soil test P, and Cu as features to predict the logistic target variable. Tissue Cu concentration varied between 7 and 105 mg Cu kg-1 in the shoot and between 73 and 1340 mg Cu kg-1 in the roots. Among soil properties, organic matter and soil test Cu most influenced the accuracy of the model. Phaseolus vulgaris, Brassica juncea, Ricinus communis, Hordeum vulgare, Sorghum vulgare, Cajanus cajan, Solanum lycopersicum, and Crotolaria spectabilis were the most efficient Cu-extracting cover crops, as shown by positive values of the logistic variable (shoot removal > root removal). Those Cu-tolerant plants showed differential capacity to extract Cu in the long run.


Assuntos
Poluentes do Solo , Biodegradação Ambiental , Fazendas , Brasil , Poluentes do Solo/análise , Cobre/análise , Solo/química , Produtos Agrícolas
2.
Environ Sci Pollut Res Int ; 30(26): 68271-68289, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37119494

RESUMO

Organic fertilization and mycorrhization can increase the phytoremediation of copper-contaminated soils. The time of vermicomposting alters the properties of vermicompost, which can affect copper's availability and uptake. Therefore, this study sought to evaluate the effect of different organic fertilizers and mycorrhization on copper-contaminated soil phytoremediation. The soil was contaminated with 100 mg Cu kg-1 dry soil and received mineral fertilizer (MIN), bovine manure (CM), and vermicompost produced in 45 days (V45) or 120 days (V120), all in doses equivalent to 40 mg kg-1 dry soil of phosphorus. Half of the jack bean (Canavalia ensiformis) plants were inoculated with the arbuscular mycorrhizal fungus Rhizophagus clarus. At plant flowering, the dry mass and concentrations of Cu, Zn, Mn, Ca, Mg, P, and K in the soil, solution, and plant tissue were determined, in addition to mycorrhizal colonization, nodulation, photosynthetic pigments, and oxidative stress enzyme activity. Organic fertilization increased plant growth and copper accumulation in aerial tissues. These effects were more evident with the V120, making it suitable for use in copper phytoextraction. Mycorrhization increased root and nodule dry mass, making it recommended for phytostabilization. C. ensiformis nodulation in Cu-contaminated soils depends on vermicompost fertilization and mycorrhization. Hence, the copper phytoremediation by C. ensiformis is increased by using organic fertilization and mycorrhization.


Assuntos
Micorrizas , Poluentes do Solo , Animais , Bovinos , Cobre/análise , Solo , Biodegradação Ambiental , Areia , Canavalia , Poluentes do Solo/análise , Fertilização
3.
J Environ Qual ; 51(5): 899-915, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35452558

RESUMO

The subtropical region of Brazil is home to 33% of the soybean [Glycine max (L.) Merr.] growing area and 90% of the wheat (Tritucum aestivum L.) growing area of this country. A soybean-wheat succession with fallow between crops is used in about 11% of the cultivated area. No study has quantified CO2 fluxes in annual soybean-wheat succession in this region. Hence, this study analyzed the seasonality of CO2 exchange (net ecosystem exchange [NEE]) in a 2015/2016 wheat-soybean succession in a commercial farm located in Carazinho, Rio Grande do Sul State, Brazil. The eddy covariance method was used to estimate the annual C balance of this system. The NEE was partitioned between gross primary productivity and ecosystem respiration to understand the dynamics of these fluxes during a year of wheat-soybean succession. Considering the net ecosystem balance between photosynthesis and respiration during the growing season, both soybean and wheat absorbed CO2 from the atmosphere (NEE wheat: -347 ± 4 g C m-2 ; NEE soybean: -242 ± 3 g C m-2 ). The fallow periods between growing seasons, however, acted as a source of 156 ± 2 g C m-2 , reducing the C absorbed by the crops by 27%. For 1 yr, the net biome productivity was -50 g C m-2  yr-1 . The results obtained here demonstrate that the wheat-soybean succession was a net C sink under these specific climatic conditions and field management practices and that the long fallow period between crops limited the agroecosystem from becoming a more efficient CO2 sink.


Assuntos
Sequestro de Carbono , Triticum , Brasil , Carbono , Dióxido de Carbono/análise , Ecossistema , Estações do Ano , Glycine max
4.
Appl Biochem Biotechnol ; 194(7): 2980-3000, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35316475

RESUMO

Research and commercial production of bioherbicides occur to a lesser extent compared to bioinsecticides and biofungicides. In order to contribute to developing new bioherbicides with low environmental impact, this study aimed to increase the phytotoxicity of metabolites of the fungus Mycoleptodiscus indicus UFSM 54 by optimizing solid and submerged fermentation and evaluate the ecotoxicological effects on earthworms (Eisenia andrei). The Plackett-Burman and central composite rotatable designs were used to optimize metabolite phytotoxicity. The variables optimized in the fermentation were temperature, agitation, pH, water volume in the culture medium, glucose concentration, and yeast extract. The fungus was grown on sugarcane bagasse substrate, and its metabolites were applied to detached Cucumis sativus, Conyza sp., and Sorghum bicolor leaves and used in an avoidance test and acute exposure to earthworms. Metabolite phytotoxicity in submerged fermentation was optimized at 35 °C, 50 rpm, and 1.5 g l-1 of glucose and in solid fermentation at 30-37 °C and in 14-32 ml of water. The metabolites severely damaged germination, initial growth, and leaves of the three plants, and at the doses tested (maximum of 113.92 ml kg-1), the metabolites of M. indicus UFSM 54 were not toxic to earthworms.


Assuntos
Celulose , Saccharum , Celulose/metabolismo , Meios de Cultura/metabolismo , Fermentação , Glucose , Saccharum/metabolismo , Água
5.
Acta sci., Biol. sci ; 44: e60908, mar. 2022. graf, tab, ilus
Artigo em Inglês | VETINDEX | ID: biblio-1391182

RESUMO

A 52-year-old pine forest is characterized as an environment with low plant diversity and large accumulation of allelopathic litter with poor nutrient content. Collembola is sensitive to environmental conditions and may have difficulties living in these forests. This study aimed (1) to evaluate the abundance and richness of Collembola in the soil of a 52-year-old pine afforestation with different moisture contents; and (2) to identify the landhopper sampled unintentionally. For sampling, pitfall traps were set up for four days, in areas of a Pinus elliottii afforestation with high and low soil moisture located at the Universidade Federal de Santa Maria. Collembola specimens were counted and identified to family and genus level. The total abundance of springtails was greater in the low soil moisture area. The genera Desoria and Lepidocyrtus, and specimens of the family Onychiuridae were more abundant in low soil moisture, meanwhile, the genus Ceratophysella was more abundant in the high soil moisture. The landhopper Talitroides sylvaticus was sampled unintentionally by traps set up in the soil with higher moisture and calcium content. Six genera of Collembola and the landhopper T. sylvaticus were identified in soil of a P. elliottii afforestation and their distribution is influenced by soil moisture.(AU)


Assuntos
Pinus/parasitologia , Infestações por Pulgas , Sifonápteros/parasitologia , Umidade do Solo , Biodiversidade
6.
Ciênc. rural (Online) ; 51(9): e20200600, 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1249559

RESUMO

ABSTRACT: Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.


RESUMO: Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.

7.
Ciênc. rural (Online) ; 51(09): 1-8, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1480204

RESUMO

Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.


Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.


Assuntos
Esterco/análise , Eucalyptus/crescimento & desenvolvimento , Fertilizantes/análise , Fertilizantes/efeitos adversos
8.
Ci. Rural ; 51(09): 1-8, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-32039

RESUMO

Composting and vermicomposting before addition to the soil is a viable alternative to the disposal of cattle manure. However, this residue has been used in the untreated form for seedling production. This study evaluated the use of cattle manure in natura, and the organic composted or vermicomposted variants of cattle manure on substrates used in the production of Eucalyptus urograndis seedlings. The treatments consisted of substrates formulated by mixing the organic fertilizers with washed sand in 20, 40, 60, 80 or 100 (v/v) percentages, compared to a commercial substrate. The E. urograndis seedlings were grown in tubes in a greenhouse and evaluated after 120 days for shoot and root dry weights, plant height, stem diameter, shoot/root ratio, and Dickson quality index. The substrate formulated from a mixture of 80% (v/v) of cattle manure in natura and washed sand allows for better development in Eucalyptus seedlings. Substrate containing 100% bovine manure vermicompost or organic compost produced seedlings with lower quality than in natura bovine manure but superior to the commercial substrate. Due to the health risks associated with use of untreated bovine manure, organic compost and vermicompost are good alternatives for the production of E. urograndis seedlings.(AU)


Uma alternativa para destinar corretamente o esterco bovino é realizar a compostagem e/ou vermicompostagem e depois adicioná-lo ao solo como fonte de nutrientes às plantas. Porém, este resíduo tem sido utilizado na produção de mudas sem tratamento. O estudo teve por objetivo avaliar o uso de esterco bovino in natura, de composto orgânico e de vermicomposto, produzidos a partir do esterco bovino, em substratos para a produção de mudas de Eucalyptus urograndis. Os tratamentos constituíram-se dos substratos formulados pela mistura dos fertilizantes orgânicos com areia lavada nas porcentagens de 20, 40, 60, 80 e 100 (v/v), em comparação com um substrato comercial (SC). As mudas de Eucalyptus urograndis foram cultivadas em tubetes, em casa de vegetação, e avaliadas aos 120 dias quanto a massa seca da parte aérea e raiz, altura da planta, diâmetro do caule, relação parte aérea/raiz e índice de qualidade de Dickson. O substrato formulado pela mistura de 80% (v/v) de esterco bovino in natura com areia lavada proporcionou o melhor desenvolvimento das mudas de eucalipto. O substrato contendo 100% de vermicomposto de esterco bovino ou composto orgânico produziu mudas com qualidade inferior ao esterco bovino in natura, mas superior ao substrato comercial. Devido aos riscos à saúde associados ao uso de esterco bovino não tratado, o composto orgânico e o vermicomposto são boas alternativas para a produção de mudas de E. urograndis.(AU)


Assuntos
Eucalyptus/crescimento & desenvolvimento , Fertilizantes/efeitos adversos , Fertilizantes/análise , Esterco/análise
9.
Braz J Microbiol ; 51(4): 1897-1908, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32737868

RESUMO

The chitinases have extensive biotechnological potential but have been little exploited commercially due to the low number of good chitinolytic microorganisms. The purpose of this study was to identify a chitinolytic fungal and optimize its production using solid state fermentation (SSF) and agroindustry substrate, to evaluate different chitin sources for chitinase production, to evaluate different solvents for the extraction of enzymes produced during fermentation process, and to determine the nematicide effect of enzymatic extract and biological control of Meloidogyne javanica and Meloidogyne incognita nematodes. The fungus was previously isolated from bedbugs of Tibraca limbativentris Stal (Hemiptera: Pentatomidae) and selected among 51 isolated fungal as the largest producer of chitinolytic enzymes in SSF. The isolate UFSMQ40 has been identified as Trichoderma koningiopsis by the amplification of tef1 gene fragments. The greatest chitinase production (10.76 U gds-1) occurred with wheat bran substrate at 55% moisture, 15% colloidal chitin, 100% of corn steep liquor, and two discs of inoculum at 30 °C for 72 h. Considering the enzymatic inducers, the best chitinase production by the isolated fungus was achieved using chitin in colloidal, powder, and flakes. The usage of 1:15 g/mL of sodium citrate-phosphate buffer was the best ratio for chitinase extraction of SSF. The Trichoderma koningiopsis UFSMQ40 showed high mortality of M. javanica and M. incognita when applied to treatments with enzymatic filtrated and the suspension of conidia.


Assuntos
Quitina/metabolismo , Quitinases/biossíntese , Fermentação , Hypocreales/enzimologia , Animais , Percevejos-de-Cama/microbiologia , Agentes de Controle Biológico , Biotecnologia , Fibras na Dieta , Nematoides/efeitos dos fármacos , Esporos Fúngicos/metabolismo , Temperatura , Zea mays
10.
Ci. Rural ; 50(6): e20190622, Apr. 27, 2020. tab
Artigo em Inglês | VETINDEX | ID: vti-28073

RESUMO

The sensory quality of wines is affected by the compounds produced by the action of the yeasts used in alcoholic fermentation. This work aimed at assessing the physicochemical, aromatic and sensory properties of the Riesling Italico white wines produced by using the Saccharomyces and non-Saccharomyces yeasts. The yeasts S. cerevisiae, S. cerevisiae cerevisiae, S. bayanus, Torulaspora delbrueckii and Metschnikowia pulcherrima were inoculated individually into the must. For 10 days, the alcohol was left to ferment in 7 L carboys in triplicate, at 15º C temperature. The standard physicochemical analyses were done and the quality of the wines was determined. The volatile compounds were identified and quantitative descriptive sensory analyses were performed. All the yeasts produced wines with the characteristic alcohol, volatile acidity and residual sugar content as stipulated by the Brazilian legislation. The T. delbrueckii yeast produced high-content phenylethyl acetate, isoamyl acetate and ethyl decanoate wines, of superior olfactory quality and sensory rating.(AU)


Durante a fermentação alcoólica as leveduras produzem compostos que influenciam a qualidade sensorial dos vinhos. O objetivo do trabalho foi avaliar as propriedades físico-químicas, aromáticas e sensoriais do vinho branco da variedade Riesling Italico elaborado a partir de leveduras Saccharomyces e não-Saccharomyces. Foram inoculadas separadamente no mosto as leveduras S. cerevisiae, S. cerevisiae cerevisiae, S. bayanus, Torulaspora delbrueckii e Metschnikowia pulcherrima. A fermentação alcoólica ocorreu em garrafões com 7 L de mosto, em triplicata, por 10 dias a 15 ºC. Foram realizadas análises físico-químicas padrão e de identificação da qualidade dos vinhos, além das análises de compostos voláteis e sensorial descritiva quantitativa. Todas as leveduras produziram vinhos com teores de álcool, acidez volátil e açúcar residual de acordo com a legislação. A levedura T. delbrueckii produz vinhos com concentrações elevadas de acetato de feniletila, acetato de isoamila e decanoato de etila, resultando em boa qualidade olfativa e avaliação sensorial.(AU)


Assuntos
Fenômenos Químicos , Odorantes , Vinho/análise , Leveduras , Alimentos Fermentados , Saccharomyces , Fermentação
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