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ABSTRACT Areas impacted by the deposition of iron mining tailings present physical and chemical characteristics that can hinder root growth, and applying soil conditioners can help alleviate these limitations. The objective was to evaluate the effect of soil conditioners in improving the environment for the growth of grass in soil affected by iron mining tailing. Four different experiments were conducted testing conditioner proportions (0, 5, 10, 25, and 50% v/v), in a completely randomized design with four replications, using Cynodon spp. The conditioners were sand, vermiculite, sawdust, and organic compost. Bulk density, macro- and microporosity, total pore volume (VTP), pH, organic matter content (OM), cation exchange capacity (CEC), and dry mass of the aboveground, root, and total plant were evaluated. There were improvements in porosity and a reduction in density with the application of vermiculite, sawdust, and organic compost; however, sand decreased the VTP. The pH was reduced with sawdust and increased with compost. Sawdust and compost increased OM. CEC increased with vermiculite and compost. The sand and vermiculite conditioners promoted the greatest growth of Cynodon spp., with emphasis on vermiculite, which provided the greatest increases in plant biomass production. The soil conditioners, overall, proved effective in improving porosity conditions, reducing density, increasing OM, and promoting plant growth, this makes this technology efficient for application in tailings. Due to its notable effect on increasing biomass and improving the environment for grass growth, vermiculite can be recommended for rehabilitation environments impacted by iron mining tailings or for post-mining revegetation.

Experimental statistics are a key element for innovation in the agricultural sector. Commonly used statistical methods in experimentation are relatively simple, reliable, and widely used. However, the many problems in the quality of statistical analyses reported in the agricultural science literature highlight a need for continuing discussion on and updating of this topic. This article reviews critical points about classic linear models procedures commonly used in agricultural statistics, frequent procedures in publications in the agricultural sciences. Due to the evolution of statistical science some common recommendations from the past should no longer be followed.

Um dos métodos mais frequentemente utilizados para obter amostras de solo sem perturbações é o método do anel volumétrico. Amostras inalteradas são utilizadas, por exemplo, na avaliação das propriedades físicas do solo, tais como densidade e porosidade. No entanto, existe uma diversidade de anéis volumétricos utilizados na investigação, o que torna difícil a comparação dos resultados obtidos nestes estudos. Assim, o objectivo desta investigação foi comparar os valores de densidade, microporosidade e porosidade total, determinados a partir da amostragem com anéis volumétricos com um volume de 100 e 272 cm³, e estabelecer a correlação entre eles, verificando se a comparação é válida. Foram recolhidas amostras de solo de 25 locais de cultivo Hapludox, que diferiam no sistema de lavoura, cultivo e/ou gestão, no município de Rio Paranaíba, MG, em diferentes profundidades. Os dados obtidos foram submetidos à análise de correlação da Pearson. A correlação entre os anéis volumétricos para todas as variáveis foi significativa, descrita pelas equações de correlação y = 0,3788 + 0,7054 * x (R = 0,68), y = 0,1342 + 0,6582 * x (R = 0,62) e y = 0,1107 + 0,6071 * x (R = 0,67), para as variáveis densidade, porosidade total e microporosidade, respectivamente. Conclui-se que a comparação dos valores das variáveis determinadas por amostragem com os dois anéis volumétricos testados é válida.

ABSTRACT: 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.

Phosphorus (P) is one of the essential macronutrients for plant growth, being a highly required resource to improve the productive performance of several crops, especially in highly weathered soils. However, a large part of the nutrients applied in the form of fertilizers becomes “inert” in the medium term and cannot be assimilated by plants. Rationalizing the use of phosphorus is a matter of extreme importance for environmental sustainability and socioeconomic development. Therefore, alternatives to the management of this nutrient are needed, and the use of P-solubilizing microorganisms is an option to optimize its use by crops, allowing the exploration of less available fractions of the nutrient in soils and reducing the demand for phosphate fertilizers. The objective of this study is to discuss the importance of phosphorus and how microorganisms can intermediate its sustainable use in agriculture. In this review study, we present several studies about the role of microorganisms as phosphorus mobilizers in the soil. We describe the importance of the nutrient for the plants and the main problems related to the unsustainable exploitation of its natural reserves and the use of chemical fertilizers. Mainly we highlight how microorganisms constitute a fundamental resource for the release of the inert portion of the nutrient, where we describe several mechanisms of solubilization and mineralization. We also discussed the benefits that the inoculation of P-solubilizing microorganisms provides to crops as well as practices of using them as bioinoculants. The use of microorganisms as inoculants is a viable resource for the future of sustainable agriculture, mainly because its application can significantly reduce the application of P and, consequently, reduce the exploitation of phosphorus and its reserves. In addition, new research must be conducted for the development of new technologies, prospecting new biological products, and improvement of management practices that allow for higher efficiency in the use of phosphorus in agriculture.

Abstract Purpose Use of silicate rock powders as fertilizer improves nutrient cycling, thus benefitting agriculture. The availability of nutrients to plants is often low, but can be increased when rock powder is vermicomposted and added. However, these powders can be rich in heavy metals, which may impair their use. We evaluated maize growth and heavy metals in plants and soil after fertilization with vermicomposted gneiss or steatite powders. Method Vermicompost was prepared with cattle manure, with or without gneiss or steatite powders. The experimental units were kept in the dark at room temperature for 70 days. Subsequently, a greenhouse experiment was carried out with maize grown in highly weathered oxisol soil and fertilized with vermicompost alone, or with gneiss or steatite powder. Results A small proportion of heavy metals was immobilized in the earthworm bodies, but did not hinder their growth. Maize growth was superior in the treatment with vermicomposted gneiss powder. The gneiss-enriched treatment contributed to increased Zn concentration in plants and may also be an alternative to Zn fertilization. High Ni and Cr concentrations in steatite powder apparently induced higher levels of these elements in plants. However, metal concentrations in the soil after cultivation in all the treatments were below acceptable limits. Conclusion Increased plant growth in gneiss-enriched vermicompost suggests the possibility of using this material to enrich vermicompost with nutrients, thus improving the chemical quality of organic fertilizer. Use of steatite powder in agriculture deserves further investigation.

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

Abstract 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.

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'.

This study evaluated the physical and chemical characteristics of the papaya ‘Solo’ cv. ‘Golden’ (Carica papaya L.) coated with propolis extract drawn from various botanical sources, during storage at room temperature. Papayas underwent three types of dip coating propolis extract, in 2.5% (w v-1) concentration (‘aqueous extract’ and ‘hydroalcoholic extract of propolis wild type’, ‘hydroalcoholic extract of the propolis green rosemary’), at ambient temperature and two controls (without coating, one at ‘ambient temperature’ and the other ‘refrigerated’). The variables weight loss, firmness, soluble solids (SS), titratable acidity (TA), maturation index ratio (SS/TA) and hydrogen potential (pH) were evaluated, at three day intervals for twelve storage days. Sensory analyses of the papayas were performed on days three and six of storage, by acceptance testing. Coatings with hydroalcoholic extract of propolis wild type and green rosemary controlled weight loss and firmness in papayas. The coatings showed no effect on the variable SS. Fruit coated with hydroalcoholic extract of rosemary green propolis showed satisfactory results evaluating AT, SS/TA and pH, as well as sensory analysis. Thus, the coating formulated with propolis extract can be used as an alternative to extend the shelf life of papaya fruits.

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.

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.

ABSTRACT 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.

ABSTRACT 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.

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.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.