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This research evaluated the importance of a preliminary general analysis of variance (ANOVA) in the interpretation of data from factorial experiments under total nullity. For this, we evaluated the familywise type I error rate (accumulated FWER) of the F test for the unfolding of factorial ANOVA and factorial ANOVA on ranks, which were compared with the FWER for the global effect of treatments. In addition, we evaluated the FWER of the Tukey’s test under total nullity for factorial experiments in the presence or absence of preliminary ANOVA protection (omnibus F test). The study was conducted by simulating data from 2,000 experiments, which were separated into four representative agricultural research scenarios. For both the parametric factorial ANOVA and the non-parametric factorial ANOVA, the FWER significantly exceeded the nominal level of 5%, even under total nullity. While the tests that control the total FWER in the factorials are not being used, the factorial ANOVA should not be performed without the preliminary ANOVA F test showing a significant effect. This, of course, does not apply to tests that are not multiple comparisons, such as Bonferroni, Dunn-Sidak and others, which do not need ANOVA protection. The same recommendation applies to the factorial ANOVA on ranks. RESUMO: Este trabalho teve como objetivo avaliar a importância da análise de variância (ANOVA) geral preliminar na interpretação dos dados de experimentos fatoriais sob nulidade total. Para isso, avaliou-se as taxas de erro tipo I familiar (FWER acumulada) do teste F para os componentes do desdobramento da ANOVA fatorial e da ANOVA fatorial on ranks, em comparação à FWER para o efeito global de tratamentos. Além disso, avaliou-se a FWER do teste de Tukey sob nulidade total para experimentos fatoriais na presença ou ausência da proteção da ANOVA preliminar (teste F global). O estudo foi conduzido a partir da simulação de dados de 2000 experimentos, separados em quatro cenários representativos da pesquisa agrícola. Tanto para a ANOVA fatorial paramétrica, quanto para a ANOVA fatorial não-paramétrica, as FWER ultrapassaram significativamente o nível nominal de 5%, mesmo sob nulidade total. Enquanto os testes que controlam a FWER total nos fatoriais não estiverem sendo utilizados, a ANOVA fatorial não deve ser realizada sem que o teste F da ANOVA preliminar acuse um efeito significativo. O mesmo, evidentemente, não se aplica aos testes que não são de comparações múltiplas, como Bonferroni, Dunn-Sidak e outros, que não precisam proteção da ANOVA. A mesma recomendação se aplica à ANOVA fatorial on ranks.

The aim of this study was to evaluate the effect of forms of application and application rates of phosphate fertilizer on the agronomic characteristics of carrot. A field experiment was car...

Swine wastewater (SW) is considered as a source of nutrients for agriculture. The quantities and frequencies applied may vary according to the soil class, the nature and composition of the waste, the climatic conditions and the cultivated plant species. Therefore, this study aimed to evaluate the effects of application of five Swine wastewater doses (0, 500, 1000, 2000 and 2500 m³ ha-1) in the production of components and grass nutrient extraction Tifton 85 and changes in soil chemical properties after the end of the last application of swine wastewater. To achieve these goals, we evaluated the quantities of extracted nutrients, density and height of the pre-grazing grass, forage accumulation rate and carrying capacity. The experimental design was a randomized block. The production of dry matter was 18159.80 kg ha-1, and the average height of 85 Tifton was 34.83 cm. The higher carrying capacity, 10 AU ha-1 was obtained with the dosage of 2500 m³ ha-1. While, the dose of 2000 m³ ha-1 supplied the nutritional needs of Tifton 85 in nitrogen, potassium, calcium, magnesium, copper, iron, zinc and boron. The quantities of extracted nutrients (kg ha-1) at grass Tifton 85 grazed were: N = 405.14; P = 57.77; K+ = 387.69; Ca2+ = 77.05; Mg2+ = 49.68; S-SO4-2 = 31.48; B = 0.33; Cu2+ = 0.20; Fe = 2.88; Mn2+ = 4.61; Zn2+ = 2.86. The application of increasing doses of SW promoted a linear increase in grass production components Tifton 85, as well, promoted changes in soil chemical properties and quantities of extracted nutrients. Key words: Pasture, liquid waste, nutrient extraction, plant growth.

This article presents a large-scale modeling analysis for different types of corridors at 10 GHz, within line-of-sight (LoS) conditions, including behavioral statistics for the received signals. Influenced by structural and material conditions, there is a 2dB increase for the stone-walled corridor, demonstrating that multipaths generated by the environment’s material permittivity are directly related to signal loss. This work contributes to the evaluation of mmWave communication performance when applied to fifth generation (5G) systems.

A saturação por base do solo pode influenciar a disponibilidade de zinco para as plantas. Portanto, objetivou-se avaliar a influência de doses de zinco e de crescentes saturações por bases de solo sobre a disponibilidade deste para plantas de milho. Para tal conduziu-se dois experimentos em casa de vegetação, sendo um referente a um solo arenoso e outro argiloso. Ambos em esquema fatorial 6 x 3, em delineamento inteiramente casualizados, com três repetições. O primeiro fator correspondeu a saturação por bases (V%) de cada solo, após curva de incubação com doses crescentes de calcário, e o segundo fator às doses estudadas de zinco (0, 5 e 25 mg dm-3). Avaliou-se a produção de matéria seca da parte área de plantas de milho, o teor e o acúmulo foliar de zinco, e o teor de zinco no solo após a condução dos experimentos. O aumento da dose de zinco proporcionou aumento de todas variáveis em estudos, em ambos experimentos, exceto para a matéria seca no solo arenoso. Esta, também, foi a única situação que os fatores atuaram de forma independente. O aumento da saturação por bases do solo proporcionou decréscimo das variáveis analisadas, sendo que o tipo de solo influencia na amplitude da resposta. Conclui-se que o aumento da dose de zinco contribui para aumento da disponibilidade e acúmulo de zinco para as plantas, sendo esta é afetada negativamente pelo aumento da saturação por bases do solo.

Purpose Silicate rock powders have been appointed as possible nutrient alternative sources which might enhance the agricultural sector sustainability. However, the application of those materials directly in soil presents as main limitations the low content and solubility of the mineral nutrient sources. In this perspective, the aim of the present study was to evaluate, in a bioweathering perspective, the conjunct application potential of phonolite with organic composts over the nutrients release in soil, as well as the production and nutrition of brachiaria grass (Urochloa decumbens). In addition, it was sought to assess the composting process effectiveness in improving the nutrient release from this rock. Method An experiment was conducted with five treatments (control; enriched compost with powder rock at 10%; mixed compost with powder rock at 10%; solely powder rock; solely compost) and four repetitions. Results The alternative sources positively influenced the productivity, as well as the K and Si contents at the aerial part of the brachiaria grass and the nutrient release in soil. However, the conjunct applications of powder phonolite with organic composts were the source which the best promoted the total nutrient biorelease to soil. Conclusion Nevertheless, there was no evidence that the composting process promotes the phonolite bioweathering. On the other hand, the conjunct application of powder phonolite with organic composts, either as an initial component to the composting pile or additive to the stabilized composts, is a strategy which enhances the nutrient biorelease of the mineral source.

Together with farmers, we evaluated nutrient availability from vermicomposted gneiss powder, assessed its influence on growth promotion, nutrition and heavy metal accumulation in maize plants and the effect on soil chemical properties in the field. Three soil treatments were applied: fertilization with vermicompost with gneiss powder, fertilization with vermicompost without gneiss powder, and soil without fertilization (control), in a randomized block design with five replicates. The dry weight of shoots and the concentrations of potassium, calcium, magnesium, manganese, nickel, chrome and lead in the dry matter of maize were higher with vermicompost with gneiss powder. In the soil, the potential of hydrogen and phosphorus, potassium and calcium concentrations were higher with vermicompost with gneiss. There were no detectable levels of heavy metal wastes in the soil after the experiment. We conclude that vermicomposted gneiss powder has potential for use in agriculture as a nutrient source and can improve soil chemical properties.

Some compounds present in coffee beans can affect consumer health. The present study determines the content of heavy metal in coffee cultivated in the Cerrado Mineiro region (Alto Paranaiba – MG, Brazil), to compare the values found with the legal standards and check how these metals are extracted from the respective infusions. Fifty samples of coffee beans were analyzed, taken from the Alto Paranaiba region, MG, Brazil. Determination and quantification were done by recording the values from the atomic absorption spectrophotometer for the metals mentioned: cadmium (Cd), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn). The Cr concentrations presented earlier the limit allowed by law in 66% of the coffee samples. And 74% of the samples contained Pb in higher than permissible concentrations. For all the infusions, the metals evaluated were found in lower concentrations and were less significant with respect to the maximum permissible daily intake, except for Pb were quantified very high levels. Only seven of the 50 coffee samples revealed results with levels that were quantified to be within the legally stipulated standards. The Pb and Cr metals were found to have the highest percentage of leaching in the coffee infusions. Key words: Coffee powder, chemical contaminants, law, drink, leaching.

Objetivou-se neste estudo avaliar físico-químicamente e sensorialmente suco misto de laranja e cenoura em diferentes concentrações. As análises físico-químicas foram realizadas em intervalos de oito dias por 22 dias de armazenamento. A análise sensorial foi realizada através do teste de aceitação no oitavo dia de armazenamento. Os sólidos solúveis e a acidez titulável não variaram entre os tratamentos. A acidez titulável variou ao longo do período de armazenamento, sendo esta variação acompanhada pelo aumento do pH. O tratamento controle apresentou menor teor de resíduo seco, diferindo do tratamento com 20% de suco de cenoura. Ao final do período de armazenamento, o teor de resíduo seco apresentou um aumento significativo. Os açúcares redutores diminuíram gradualmente em todos os tratamentos no decorrer do período de armazenamento dos sucos. Os tratamentos com 10% e 20% de suco de cenoura obtiveram melhor aceitação, não tendo sido verificado diferença significativa entre o tratamento controle. The objective of this study was to evaluate physico-chemically and sensorially mixed juice of orange and carrot in different concentrations. Physical chemistry analyzes were performed at eight-day intervals for 22 days of storage. Sensory analysis was performed through the acceptance test on the eighth day of storage. Soluble solids and titratable acidity did not vary between treatments. The titratable acidity varied over the storage period, this variation being accompanied by the increase in pH. The control treatment had lower content of dry residue, differing from the treatment with 20% of carrot juice. At the end of the storage period, the dry residue content showed a significant increase. Reducing sugars gradually decreased in all treatments over the juice storage period. The treatments with 10% and 20% of carrot juice obtained better acceptance, not having been verified significant difference between the control treatment.

A diagnose foliar é o método de maior relevância na definição e na interpretação do estado nutricional das plantas. A interpretação correta sobre o estado nutricional da cultura só é possível quando se regionalizam os valores de referência. Objetivou-se, com este trabalho, determinar índices diagnósticos para interpretação de resultados de análise foliar de milho mediante o uso dos métodos de interpretação: Nível crítico (NC), Faixa de suficiência (FS) e Índices Balanceados de Kenworthy (IBK). Amostraram-se solos, folhas e produtividade em 120 lavouras de milho, nas safras agrícolas 2010/2011 e 2011/2012, na região do Alto Paranaíba, MG. Para gerar os índices diagnósticos pelos métodos FS e IBK a população foi dividida em duas subpopulações, com base na produtividade: acima ou abaixo de 11.795 kg ha-1. Os teores de nutrientes propostos como adequados pelos métodos citados foram semelhantes. A amplitude das faixas ótimas foi menor que a encontrada na literatura para milho. Os índices diagnósticos regionalizados pelos métodos NC, FS e IBK aumentam a confiabilidade ao diagnosticar talhões com as mesmas características das normas estabelecidas em relação a valores de referência universal. At present, the leaf analysis is the method of greatest relevance in the definition and interpretation of nutritional status of plants. The correct interpretation of the nutritional status of the crop is only possible when it regionalizes reference values (standards). This study aimed to determine reference values for the interpretation of the results of leaf analysis of maize through the use of methods of interpretation: critical levels (CL), sufficiency range (SR) and balanced indexes of Kenworthy (BIK). Sampling of soil, leaves and productivity was conducted in 120 commercial crops of corn, in the crop year of 2010/2011 and 2011/2012, in the region of Alto Paranaíba, MG. To generate the diagnostic indexes by the methods SR and BIK, the population was divided into two sub-populations: with the productivity above and below 11,795 kg ha-1. Levels and normal ranges proposed by the cited methods were very similar. The amplitude of optimum ranges were lower when compared to that one found in the literature. The diagnostic indexes regionalized by the methods CL, SR and BIK increased the reliability when diagnosing plots with the same characteristics of the standards approved in relation to universal reference values.

Objetivou-se neste trabalho avaliar o efeito de diferentes formulações à base de glyphosate sobre a colonização micorrízica e nodulação no cultivar de soja RR TMG 125. Os experimentos foram desenvolvidos em condições de campo, em Latossolo Vermelho-Amarelo, durante os anos agrícolas 2010/2011 e 2011/2012. Os tratamentos constaram da aplicação da dose de 720 g e.a. ha-1 das seguintes formulações de glyphosate: Trop®, Roundup Original®, Roundup Ultra®, Roundup WG®, Roundup Transorb R® e Zapp Qi®, além de duas testemunhas (capinada e não capinada). Utilizou-se o delineamento em blocos casualizados com quatro repetições. A matéria seca da parte aérea, nodulação e produtividade de soja não foram influenciadas pelas diferentes formulações de glyphosate. Para a colonização micorrízica, observou-se efeito positivo da formulação Roundup Original®, em relação à testemunha capinada; no entanto, esse efeito não foi contínuo nos dois anos de experimento. A variável número de nódulos foi mais afetada pelas formulações de glyphosate testadas. The aim of this study was to evaluate the effect of different glyphosate-based formulations on mycorrhizal colonization and nodulation in soybean cultivar RR TMG 125. The experiments were conducted under field conditions in Red-Yellow Latosol, during 2010/2011 and 2011/2012. The formulations Trop®, Roundup Original®, Roundup Ultra®, Roundup WG®, Roundup Transorb R® and ZappQi® were used at a glyphosate dose of 720 g a.e. ha-1. The experiment was arranged in a randomized block design with four replications and two controls (hoed control and non-hoed control). The variables shoot, nodule dry matter, and soybean yield were not influenced by the different formulations of glyphosate. For mycorrhizal colonization, it was verified that a positive effect of the herbicide Roundup Original® regarding the hoed control was not continuous in the two years of the experiment. The variable number of nodules was the most affected by the glyphosate formulations tested.

The high perishability of papaya (Carica papaya L.) reduces its lifespan as well as limits marketing. Coating the fruits is an alternative to aid food preservation. We aimed to evaluate the effects of coating propolis extract on the physicochemical characteristics of papaya stored at room temperature. Solo papayas cv. 'Golden' were randomly divided into five postharvest treatment groups, three forms of dip-coating (70% alcohol, hydroalcoholic extract of propolis to 2.5%, and hydroalcoholic extract of propolis to 5%) and two controls (one uncoated and one with refrigerated uncoated fruits). The weight loss, firmness, soluble solids (SS), titratable acidity (TA), SS/TA, and hydrogen potential (pH) were evaluated at the intervals of 4 days every 12th storage day. Sensory analysis was performed on the 4th day of storage of papayas and evaluated by untrained through the acceptance testing. Treatments “refrigerated”, “propolis 2.5%”, and “5% propolis” presented with the lowest weight loss. The firmness level for treatment propolis 5% was superior to that of control, alcohol, and 2.5% propolis treatments. The SS was greater for propolis 5% treatment, which only differed from the alcohol treatment. The TA and SS/TA did not vary with the treatments, but with the storage time. The pH of refrigerated papaya showed significant differences in relation to other treatments. The fruits subjected to refrigerated treatment presented with chilling injury. Papayas coated with propolis extract showed sensory acceptability similar to that in other treatments on the 4th day of storage. The coating of propolis extract is a promising alternative for the control of weight loss and for the maintenance of firmness in Solo papaya cv. 'Golden'. A alta perecibilidade do mamão (Carica papaya L.) reduz sua vida útil limitando sua comercialização. Os revestimentos são uma das alternativas para auxiliar na conservação de alimentos. Objetivou-se avaliar os efeitos do revestimento com extrato de própolis nas características físico-químicas do mamão, armazenado sob temperatura ambiente. Mamões Solo cv. ‘Golden’ foram selecionados e divididos aleatoriamente em cinco tratamentos pós-colheita, sendo três formas de revestimento por imersão (“álcool 70%”, “extrato hidroalcoólico de própolis a 2,5%”, “extrato hidroalcoólico de própolis a 5%”) e dois controles (um sem revestimento e outro em que os frutos não foram revestidos e mantidos sob refrigeração). As variáveis perda de massa, firmeza da polpa, sólidos solúveis (SS), acidez titulável (AT), relação entre sólidos solúveis e acidez titulável (SS/AT) e potencial hidrogeniônico (pH), foram avaliadas em intervalos de 4 dias por 12 dias de armazenamento. Realizou-se análise sensorial no quarto dia de armazenamento dos mamões, avaliados por provadores não treinados através do teste de aceitação. Os tratamentos pós-colheita “refrigerado”, “própolis 2,5%” e “própolis 5%” propiciaram menor perda de massa. A firmeza da polpa para o tratamento pós-colheita “própolis 5%” apresentou-se superior aos tratamentos pós-colheita “controle”, “álcool” e “própolis 2,5%”. O teor de SST foi maior para o tratamento pós-colheita “própolis 5%”, que diferiu somente do tratamento pós-colheita “álcool”. A AT e a relação SS/AT não variaram com os tratamentos pós-colheita, variando somente com o tempo de armazenamento. O pH dos mamões refrigerados apresentaram diferenças significativas em relação aos demais tratamentos pós-colheita. Os frutos do tratamento “refrigerado” apresentaram injúria pelo frio. Mamões revestidos com extrato de própolis apresentaram aceitação sensorial semelhantes aos demais tratamentos pós-colheita no quarto dia de armazenamento. O revestimento de extrato de própolis pode ser uma alternativa promissora no controle da perda de massa e manutenção da firmeza da polpa em mamão Solo cv. ‘Golden’.

Due to its ease of obtaining, handling, price and biological value, the egg is one of the most consumed foods in the world. However, because it is basically for in natura use, offers risks when care is not observed on its handling, storage and shelf life. The objective of this research was to increase the shelf life of hens eggs (Gallus domesticus) using the bee propolis (Apis mellifera). Eggs were covered with a film of propolis and these eggs were compared with uncovered ones: unwashed and washed eggs. Weight loss, density, Haugh unit, height of the air chamber and survey of total coliform, coliform and Salmonella were evaluated. The coverage with propolis provided less weight loss, lower reduction of density and loss of the Haugh unit. The process also allow to kept the size of the air chamber. No coliforms or Salmonella were found in eggs coated with propolis. Thus, it was observed that the coverage of eggs with propolis increases the shelf life and maintains internal and microbiological qualities of the eggs. Devido a sua facilidade de obtenção, manejo, preço e valor biológico, o ovo é um dos alimentos mais consumidos no mundo. No entanto, por ser basicamente utilizado in natura, oferece risco quando alguns cuidados não são observados em seu manuseio, armazenamento e prazo de validade. O objetivo deste trabalho foi estender o período de validade dos ovos através do uso de própolis de abelhas (Apis mellifera). Os ovos foram cobertos com uma película de própolis e comparados com ovos não lavados e lavados. Foram avaliadas a perda de massa, massa específica, unidade Haugh, altura da câmara de ar e a presença de bactérias dos grupos coliformes totais, termotolerantes e do gênero Salmonella. A cobertura com própolis promoveu menor perda de massa, menor redução da massa específica, menor perda da unidade Haugh com manutenção do tamanho da câmara de ar. Coliformes ou bactérias do gênero Salmonella não foram encontrados em ovos revestidos com própolis. Assim, observou-se que a cobertura de ovos com própolis mantém as qualidades internas e microbiológicas por mais tempo, aumentando a vida de prateleira dos mesmos.

The growth of earthworms in substrates enriched with rock (gneiss and steatite) powder, and the potential of vermicomposting in increasing solubilisation of minerals present in rock powder and in promoting plant growth were evaluated. Cattle manure (400 g), was enriched with 0, 5 and 20% of gneiss or steatite powder. Each pot with this mixture received nine earthworms ( Eisenia andrei ), at a density of 1000 indiv. m −3 . After 60 d, earthworms were collected, counted and weighed (fresh and dry). Maize was cultivated in a greenhouse in pots with an Oxisol that was fertilised with the vermicompost obtained above. Treatments with Oxisol fertilised with gneiss or steatite only and unfertilised soil were used as controls. Shoot length was measured weekly from the soil surface to the tips of the leaves. After 73 d, the plants were harvested, the roots washed from the soil and shoots and roots dried and weighed. Plants fertilised with vermicompost enriched with rock powder were taller and heavier than plants fertilised with non-enriched vermicompost. Plants grown on soil fertilised with rock powder but not with vermicompost were larger than plants grown on unfertilised soil. Vermicompost enriched with steatite powder resulted in a larger effect on plant growth than the mere sum of applying vermicompost of non-enriched manure and steatite alone to the soil. A similar, but non-significant effect was also observed for gneiss. The different effects between gneiss and steatite may be associated with the lower resistance to chemical weathering of steatite minerals compared to gneiss minerals, as well as the former being softer than the latter. The effect of vermicompost on the optimisation of nutrient release from silicate rocks seems to depend on the rock type.

Experimental statistical procedures used in almost all scientific papers are fundamental for clearer interpretation of the results of experiments conducted in agrarian sciences. However, incorrect use of these procedures can lead the researcher to incorrect or incomplete conclusions. Therefore, the aim of this study was to evaluate the characteristics of the experiments and quality of the use of statistical procedures in soil science in order to promote better use of statistical procedures. For that purpose, 200 articles, published between 2010 and 2014, involving only experimentation and studies by sampling in the soil areas of fertility, chemistry, physics, biology, use and management were randomly selected. A questionnaire containing 28 questions was used to assess the characteristics of the experiments, the statistical procedures used, and the quality of selection and use of these procedures. Most of the articles evaluated presented data from studies conducted under field conditions and 27 % of all papers involved studies by sampling. Most studies did not mention testing to verify normality and homoscedasticity, and most used the Tukey test for mean comparisons. Among studies with a factorial structure of the treatments, many had ignored this structure, and data were compared assuming the absence of factorial structure, or the decomposition of interaction was performed without showing or mentioning the significance of the interaction. Almost none of the papers that had split-block factorial designs considered the factorial structure, or they considered it as a split-plot design. Among the articles that performed regression analysis, only a few of them tested non-polynomial fit models, and none reported verification of the lack of fit in the regressions. The articles evaluated thus reflected poor generalization and, in some cases, wrong generalization in experimental design and selection of procedures for statistical analysis.

In the present work were evaluated the effects of propolis coatings of various botanical sources on quality traits of bananas cv. Prata (Musa sapientum L.) stored at room temperature. ´Prata´ bananas were selected and submitted to five postharvest treatments: four coatings applied by immersion in propolis extracts at a concentration of 2.5% (w/v) and a control (without coating). Propolis extracts were applied as 1) a wild type aqueous propolis extract, 2) a wild type hydroalcoholic propolis extract, 3) a rosemary green type hydroalcoholic propolis extract and 4) a red type hydroalcoholic propolis extract. The bananas were evaluated at three-day intervals along 12 days for fresh weight losses, flesh firmness, soluble solids (SS), titratable acidity (TA), the ratio SS/TA and pH. Sensory analyses were performed after three and six days of storage by 55 not trained panelists designed for acceptability. At the end of the twelve-day storage period, bananas coated either with the rosemary green hydroalcoholic extract or with the aqueous extract presented lower fresh weight losses in comparison to the bananas of the control treatment. No differences were determined in relation to flesh firmness and along the storage period TA values decreased and pH values increased in bananas of all treatments. SS contents increased towards the end of the storage period that, consequently, contributed to increases in the SS/TA ratio. The most significant increase in SS/TA ratio was determined in bananas coated with the red type hydroalcoholic extract. Taste panelists did not detect significant differences amongst coated and not coated cv. Prata bananas up to six days of storage. RESUMO Este trabalho foi realizado com o objetivo de avaliar os efeitos do revestimento com extrato de própolis de diferentes fontes botânicas sobre as características físico-químicas de banana ‘Prata’ (Musa sapientum L.), armazenada à temperatura ambiente. Bananas ‘Prata’ foram selecionadas e submetidas à cinco tratamentos pós-colheita, sendo quatro formas de revestimento por imersão em extrato de própolis de diferentes fontes botânicas com concentração de 2,5% (m/v) (“extrato aquoso de própolis do tipo silvestre”, “extrato hidroalcoólico de própolis do tipo silvestre”, “extrato hidroalcoólico de própolis do tipo verde alecrim e “extrato hidroalcoólico de própolis do tipo vermelho ”) e um controle (sem revestimento). As variáveis avaliadas foram perda de massa, firmeza da polpa, sólidos solúveis (SS), acidez titulável (AT), relação entre sólidos solúveis e acidez titulável (SS/AT) e potencial hidrogeniônico (pH), realizadas em intervalos de 3 dias por 12 dias de armazenamento. Realizou-se a análise sensorial das bananas aos 3 e 6 dias de armazenamento, avaliadas por 55 provadores não treinados através do teste de aceitação. Ao final de 12 dias de armazenamento, os revestimentos de extrato de própolis “verde” e “aquoso” reduziram a perda de massa em banana ‘Prata’, quando comparados ao tratamento pós-colheita “controle”. Neste mesmo período, não foi observado diferenças entre os tratamentos pós-colheita na firmeza da polpa dos frutos. Verificou-se a ocorrência de menores valores de AT e maiores valores de pH em todos os tratamentos pós-colheita no decorrer do amadurecimento dos frutos. O teor de SS aumentou ao final do período de armazenamento, que consequentemente, contribuiu para elevar a relação de SS/AT nos tratamentos pós-colheita, sendo mais significativo no tratamento pós-colheita “vermelho”. Sensorialmente, as bananas ‘Prata’ não apresentaram diferenças significativas entre os tratamentos pós-colheita com e sem revestimento de extrato de própolis, apresentando características sensoriais similares até o 6º dia de armazenamento.

Farmers must carefully choose the cultivar to be grown for a successful carrot crop. The yield potential of the cultivar may influence nutrient demand and should be known to plan for fertilization application. The aim of this study was to evaluate the cultivar effect on carrot yield and on the nutrient content and quantities allocated to leaves and roots. Three experiments were set up in two crop seasons in Rio Paranaíba, MG, Brazil. In the first season, typical summer, 10 summer cultivars were sown. In the second season, summer-winter (transition), two experiments were set up, one with summer cultivars and the other with winter cultivars. The treatments consisted of the carrot cultivars distributed in randomized blocks with four replications. Fresh and dry matter of the roots and leaves was quantified. Yield was calculated based on fresh matter of the roots. The nutrient content in leaves and roots was determined at the time of harvest. These contents and the dry matter production of roots and leaves were used to calculate nutrient uptake and export. The greatest average for total and commercial yield occurred in the crop under summer conditions. Extraction of N and K for most of the cultivars in the three experiments went beyond the amounts applied through fertilizers. Thus, there was contribution of nutrients from the soil to obtain the yields observed. However, the amount of P taken up was considerably less than that applied. This implies that soil P fertility will increase after cropping. The crop season and the cultivars influenced yield, nutrient content in the leaves and roots, and extraction and export of nutrients by the carrot crop. A escolha da cultivar de cenoura deve ser planejada cuidadosamente pelo agricultor para o sucesso da exploração da cultura. O potencial produtivo da cultivar pode influenciar a demanda de nutrientes e deve ser conhecido para estabelecer o plano de fertilização. Objetivou-se, com este trabalho, avaliar o efeito de cultivares sobre a produtividade de cenoura, o teor e as quantidades alocadas de nutrientes em folhas e raízes. Foram implantados três experimentos em duas épocas de cultivo em Rio Paranaíba, MG. Na primeira época, caracterizada como verão típico, foram semeadas 10 cultivares de verão. Na segunda, evidenciada como verão-inverno (transição), instalaram-se dois experimentos, um com cultivares de verão; e outro, de inverno. Os tratamentos consistiram das cultivares de cenoura, distribuídos em blocos casualizados, com quatro repetições. Quantificaram-se a matéria fresca e a seca de raízes e folhas. Com base na matéria fresca de raízes, calculou-se a produtividade. Determinou-se o teor de nutrientes em folhas e raízes por ocasião da colheita. Calcularam-se, com bases nesses teores e na produção de matéria seca de raízes e folhas, a absorção e exportação de nutrientes. A maior média de produtividades total e comercial ocorreu no cultivo em condições de verão. A extração de N e K para a maioria das cultivares nos três experimentos superou as quantidades aplicadas via fertilizantes. Assim, houve contribuição dos nutrientes no solo para obter as produtividades alcançadas. Entretanto, para o P, a quantidade absorvida foi consideravelmente menor que a aplicada. Isso implicou que o solo teve sua fertilidade aumentada em P, após o cultivo. A época de cultivo e as cultivares influenciaram a produtividade, os teores de nutrientes nas folhas e raízes, a extração e a exportação de nutrientes pela cultura da cenoura.

Surfactants and inorganic ligands are pointed as efficient to simultaneous removal of heavy metals and hydrophobic organic pollutants from soil. However, the biosurfactants are potentially less toxic to soil organisms than other chemical agents. Thus, in this study the efficiency of combinations of iodide (I(-)) ligand and surfactants produced by different bacterial species in the simultaneous removal of cadmium (Cd(2+)) and phenanthrene in a Haplustox soil sample was investigated. Four microbial surfactants and the synthetic surfactant Triton X-100 were tested with different concentrations of ligand. Soil samples contaminated with Cd(2+) and phenanthrene underwent consecutive washings with a surfactant/ligand solution. The removal of Cd(2+) increased with increased ligand concentration, particularly in solutions containing biosurfactants produced by the bacterial strains Bacillus subtilis LBBMA155 (lipopeptide) and Flavobacterium sp. LBBMA168 (mixture of flavolipids) and Triton X-100. Maximum Cd(2+) removal efficiency was 99.2% for biosurfactant produced by Arthrobacter oxydans LBBMA 201 (lipopeptide) and 99.2% for biosurfactant produced by Bacillus sp. LBBMA111A (mixed lipopeptide) in the presence of 0.336 mol iodide l(-1), while the maximum efficiency of Triton X-100 removal was 65.0%. The biosurfactant solutions removed from 80 to 88.0% of phenanthrene in soil, and the removal was not influenced by the presence of the ligand. Triton X-100 removed from 73 to 88% of the phenanthrene and, differently from the biosurfactants, iodide influenced the removal efficiency. The results indicate that the use of a single washing agent, called surfactant-ligand, affords simultaneous removal of organic contaminants and heavy metals.

This work aimed at evaluating the biodegradability of different bacterial surfactants in liquid medium and in soil microcosms. The biodegradability of biosurfactants by pure and mixed bacterial cultures was evaluated through CO(2) evolution. Three bacterial strains, Acinetobacter baumanni LBBMA ES11, Acinetobacter haemolyticus LBBMA 53 and Pseudomonas sp. LBBMA 101B, used the biosurfactants produced by Bacillus sp. LBBMA 111A (mixed lipopeptide), Bacillus subtilis LBBMA 155 (lipopeptide), Flavobacterium sp. LBBMA 168 (mixture of flavolipids), Dietzia Maris LBBMA 191(glycolipid) and Arthrobacter oxydans LBBMA 201(lipopeptide) as carbon sources in minimal medium. The synthetic surfactant sodium dodecyl sulfate (SDS) was also mineralized by these microorganisms, but at a lower rate. CO(2) emitted by a mixed bacterial culture in soil microcosms with biosurfactants was higher than in the microcosm containing SDS. Biosurfactant mineralization in soil was confirmed by the increase in surface tension of the soil aqueous extracts after incubation with the mixed bacterial culture. It can be concluded that, in terms of biodegradability and environmental security, these compounds are more suitable for applications in remediation technologies in comparison to synthetic surfactants. However, more information is needed on structure of biosurfactants, their interaction with soil and contaminants and scale up and cost for biosurfactant production.

Agroforestry systems can be a viable alternative to the preservation of natural resources while contributing to sustainable food production in the tropics. These perennial systems promote beneficial biological interactions between micro-organisms and plant species, especially those formed by arbuscular mycorrhizal fungi and roots. Mycorrhizal fungi increase the soil volume explored by the roots, increase nutrient absorption by the plants, protect the root system against pathogens, toxic elements and certain heavy metals, help the formation and maintenance of soil structure, increase the input of soil carbon, and contribute to the maintenance of biodiversity. Agroforestry systems have the potential to maximize the benefits associated with AMF, which in turn could mitigate negative interactions between trees and annual crops. This beneficial impact between agroforestry management and mycorrhizal action may be depicted as a particular form of symbiosis, and deserves more study.

No Brasil, as espécies Pinus elliottii e Terminalia ivorensis vêm sendo indicadas para reflorestamento. No entanto, pouco se sabe sobre as características ecológicas destas florestas, o ciclo de nutrientes e suas conseqüências sobre a produtividade e sustentabilidade sob condições tropicais. Visando melhor compreender a dinâmica do C nestes ecossistemas, objetivou-se neste trabalho avaliar a atividade microbiana do solo, serapilheira e da mistura solo + serapilheira em povoamentos florestais de P. elliottii e T. ivorensis. Amostras de solos e serapilheira foram incubadas e a atividade microbiana avaliada por meio da evolução de CO2. Ao final da incubação, a respiração acumulada foi superior para a serapilheira de T. ivorensis. Os demais substratos com serapilheira não diferiram entre si, mas diferiram do solo sob T. ivorensis, que, por sua vez, diferiu do solo sob P. elliottii. Nas condições testadas, a incorporação de solo à serapilheira, bem como a incorporação alternada de solo de um povoamento à serapilheira de outro, não promoveu aumentos significativos na respiração da serapilheira, mostrando que as características químicas da própria serapilheira alteram mais fortemente sua velocidade de degradação que as características químicas e microbianas do solo onde é incorporada. ______________________________________________________________________________ SUMMARY In Brazil, the species Pinus elliottii and Terminalia ivorensis are being recommended for reforestation. However, little is known about the ecological characteristics of such forests, the nutrient cycle and possible consequences on yields and sustainability under tropical conditions. For a better understanding of the C dynamic in these ecosystems, this study aimed to evaluate the microbial activity of soil, litter, and the mixture of soil + litter in forest stands of P. elliottii and T. ivorensis. Samples of soil, litter and mixture were incubated and the microbial activity was evaluated on the basis of CO2 released. At the end of incubation, the accumulated respiration was significantly higher in litter of T. ivorensis. The other substrates with litter did not differ from each other, but differed from the soil under T. ivorensis, which in turn differed from soil under P. elliottii. In the tested conditions, the soil incorporation to litter, as well as the alternate incorporation of soil from one forest with the litter of another did not cause a significant increase in litter respiration. This indicates that the influence of the chemical characteristics of the litter itself on degradation speed is stronger than the chemical and microbiological characteristics of the soil where it is incorporated.

Devido a sua facilidade de obtencao, manejo, preco e valor biologico, o ovo e um dos alimentos mais consumidos no mundo. No entanto, por ser basicamente utilizado in natura , oferece risco quando alguns cuidados nao sao observados em seu manuseio, armazenamento e prazo de validade. O objetivo deste trabalho foi estender o periodo de validade dos ovos atraves do uso de propolis de abelhas ( Apis mellifera) . Os ovos foram cobertos com uma pelicula de propolis e comparados com ovos nao lavados e lavados. Foram avaliadas a perda de massa, massa especifica, unidade Haugh, altura da câmara de ar e a presenca de bacterias dos grupos coliformes totais, termotolerantes e do genero Salmonella . A cobertura com propolis promoveu menor perda de massa, menor reducao da massa especifica, menor perda da unidade Haugh com manutencao do tamanho da câmara de ar. Coliformes ou bacterias do genero Salmonella nao foram encontrados em ovos revestidos com propolis. Assim, observou-se que a cobertura de ovos com propolis mantem as qualidades internas e microbiologicas por mais tempo, aumentando a vida de prateleira dos mesmos.