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The effects of iron, manganese, zinc, copper, and lead on the chlorophyll content, carbon assimilation, and the antiradical activity of Rhizophora mangle and Laguncularia racemosa were evaluated in regions affected by the Fundão dam disruption in Brazil. The mine waste which settled and accumulated in the sediments could represent long-term contamination. It can be expected that the iron oxyhydroxides deposited in the sediments will be solubilized, leading to chronic contamination by trace metals and the accumulation of these metals in the biota. In this sense, biological indicators prove to be important tools to assess this type of damage. The different bioaccumulation of metals by the species revealed that R. mangle was more impacted by Mn and Cu and that L. racemosa showed alterations in its physiological responses in the presence of Cu, Zn, and Fe. The concentration of these metals in the leaves, with values above previous local reference limits, was associated with reductions in the chlorophyll-a and chlorophyll-b content and carbon assimilation, mainly in L. racemosa. The antiradical activity was also altered, suggesting a lower ability of both species to eliminate reactive oxygen species (ROS). A possible reason for the symptoms of oxidative stress may be due to the reduced efficiency of antioxidant defense by Cu2+ and Zn2+. In addition, the presence of Pb in the leaf tissue may be toxic to the fauna and the bioaccumulation of this metal and trace elements can be a way to transfer them into the food web by biomagnification.

Quantifying soil gas emissions is costly, since it requires specific methodologies and equipment. The objective of this study was to evaluate modeling by nonlinear regression and artificial neural networks (ANN) to estimate CO2 emissions caused by soil managements. CO2 emissions were evaluated in two different soil management systems: no-tillage and minimum tillage. Readings of CO2 flow were carried out by an automated closed system chamber; soil temperature, water content, density, and total organic carbon were also determined. The regression model and the ANN models were adjusted based on the correlation of the variables measured in the areas where the soil was managed with no-tillage and minimum tillage with data of CO2 emission. Artificial neural networks are more accurate to determine correlations between CO2 emissions and soil temperature, water content, density, and organic carbon content than linear regression. RESUMO A quantificação das emissões destes gases do solo é onerosa, uma vez que requer metodologias e equipamentos específicos. O objetivo deste foi avaliar a modelagem utilizando regressão não linear e redes neurais artificiais para estimar a emissão de CO2 em função do manejo do solo, e de suas propriedades físicas e químicas. A emissão de CO2 foi avaliada em dois diferentes manejos do solo, o plantio direto e o cultivo mínimo. As leituras de fluxo CO2 foram realizadas por meio de uma câmara de sistema fechado automático, determinou-se ainda a temperatura e teor de água do solo, densidade do solo e carbono orgânico total. O modelo de regressão e os modelos de redes neurais artificiais foram ajustados a partir da correlação entre as variáveis medidas nas áreas em que o solo foi manejado com plantio direto e cultivo mínimo, com os dados de emissão de CO2. As redes neurais artificiais são mais precisas na determinação das relações entre a emissão de CO2 e a temperatura, teor de água no solo, densidade do solo e carbono orgânico, quando comparado com os resultados de regressão linear.

Nitrogen (N) is the most applied nutrient in Coffea canephora crop. However, the absorption of N, especially in the form of nitrate, does not guarantee its effective use in the synthesis of biomole...

The Diagnosis and Recommendation Integrated System (DRIS) is a tool to assess the nutritional state of plants. Due to the decrease of soil fertility in pasture areas and little information about fertilization recommendations, the nutritional reference norms for soil and sufficiency range can be useful tools to help future fertilization. Norms DRIS has been proved efficient as a method for nutritional diagnosis in several crops. However, there are a lack of information on the use of DRIS and sufficiency range for Latosols and Acrisols cultivated with Urochloa brizantha. Thus, the objective of the present study was to establish reference nutritional norms using sufficiency ranges and DRIS norms for Latosols and Acrisols cultivated with Urochloa brizantha and their use in nutritional diagnosis. Soils samples from 20 Urochloa brizantha pastures sites of the North of Espírito Santo State were used to establish the reference norms, and a further 85 soils samples were randomly collected for diagnosis analysis, in order to characterize nutritional condition of pastures. DRIS norms and sufficiency ranges were established for Latosols and Acrisols cultivated with U. brizantha pastures. The differences found between soil norms for other Brazilian regions allow us to infer that the norms should be used only in the conditions in which they were developed. Our results suggest that using DRIS norms and sufficiency ranges developed on the basis of soil analysis revealed deficiency of P, B, Cu, and Zn in more than 40% of the pastures cultivated with U. brizantha and 47% of the areas needed liming.

An adequate nutritional management is essential to ensure high coffee yields. In view of the wide genetic variability among Coffea canephora genotypes, due to the allogamy of the species, the nutri...

The evaluation of the physical attributes of the soil is of fundamental importance for the understanding of the impacts caused by the different uses in the agricultural systems. In this sense, the objective of this work was to evaluate the changes in physical attributes of the soil in an area with different uses located in the north of Espírito Santo. The experiment followed a randomized block design (DBC), in a 4 × 2 factorial scheme, represented by 4 areas (coffee, fruit, pasture and native forest) and 2 depth classes (0-10 and 10-20 cm), resulting in a total of 8 treatments with 5 replications. The physical attributes evaluated were: texture, Ds (soil density); Dp (particle density); Ma (macroporosity); Mi (microporosity) and Pt (total porosity). The data obtained were submitted to analysis of variance and the comparison of means was performed using the Tukey test at 5%, using the statistical program R© 4.2. Then, the physical attributes data were grouped into a similarity dendrogram, using the Euclidean distance method. The area with native forest presented the best physical attributes of the soil, followed by: coffee, fruit and pasture, not differing in depth. As for the analysis by grouping, native forest was similar to coffee growing and fruitful showed the greatest dissimilarity between land uses, especially in relation to forest.

Molybdenum (Mo) availability is strongly affected by soil pH, which determines the dynamics of electrical charges and the adsorption of molybdate. This study evaluated the effects of nitrogen (N) and Mo application on the chemical properties of a Latossolo Amarelo (Oxisol) and in Coffea canephora nutrition and productivity throughout two productive cycles under field conditions. The experiment was conducted from June 2018 to May 2020. The experimental design used was in randomized blocks, in a 2 × 5 factorial scheme, the first factor being the absence and presence (4 kg ha-1 yr-1) of molybdic fertilization and the second factor was the N dose (300, 500, 700, 900, and 1,100 kg ha-1 yr-1). At the end of each production cycle, soil samples were collected to evaluate the pH(H2O), pH(KCl), exchangeable aluminum, potential acidity, organic matter, and Mo, at layers of 0.00-0.20 and 0.20-0.40 m. Leaves were sampled from the coffee tree to determine Mo and N contents and the coffee beans were harvested to evaluate the yield of processed coffee. The results showed that urea has a high potential for soil acidification, influencing the values of exchangeable aluminum, potential acidity, and ∆pH, at layers of 0.00-0.20 and 0.20-0.40 m. The decrease in pH caused by increasing doses of N increased the density of positive electrical charges of the soil and reduced Mo content in the leaves of C. canephora by 67 %. The application of sodium molybdate via soil was efficient in providing Mo to Conilon coffee and provided a 3.7 % increase in the yield of processed coffee. Nevertheless, molybdic fertilization did not influence the Mo content in the soil in the evaluations carried out at the end of each production cycle.

The objective of this work was to determine the macronutrient dynamics in leaves and bunches of black pepper (Piper nigrum) throughout the plant reproductive cycles. The experiment was carried out in a commercial field of 'Bragantina' black pepper. Leaves and bunches were sampled every 21 days for one year, during two crop cycles. The bunches were sampled from the twenty eighth day after the appearance of inflorescences until the complete fruit maturation. Samples of leaves and bunches were dried, and the contents of N, P, K, Ca, Mg, and S were determined. N, K, and Ca were the most common macronutrients found in the bunches and leaves of black pepper. The accumulation of dry matter in the bunches was similar for both cycles and it was adjusted to the linear and quadratic models. The accumulation and content of macronutrients followed the dry matter behavior trend. Macronutrient contents in leaves oscillate during the year, and K and Mg vary more than N, P, Ca, and S. The macronutrient contents in black pepper leaves and bunches depends on the plant vegetative stage, and this variation should be considered in the planning of the fertilization management. Resumo: O objetivo deste trabalho foi determinar a dinâmica de macronutrientes em folhas e cachos de pimenta-do-reino (Piper nigrum), ao longo dos ciclos reprodutivos da planta. O experimento foi realizado em uma lavoura comercial de pimenta-do-reino 'Bragantina'. Folhas e cachos foram amostrados a cada 21 dias, por um ano, durante dois ciclos de cultivo. Os cachos foram amostrados desde o vigésimo oitavo dia após o lançamento das inflorescências até a maturação completa dos frutos. As amostras de folhas e cachos foram secas, e os conteúdos de N, P, K, Ca, Mg e S foram determinados. N, K e Ca foram os macronutrientes mais comuns nos cachos e nas folhas de pimenta-do-reino. O acúmulo de matéria seca nos cachos de pimenta-do-reino foi similar nos dois ciclos e foi ajustado aos modelos linear e quadrático. O acúmulo e o conteúdo de macronutrientes seguiram a tendência de comportamento da matéria seca. O conteúdo de macronutrientes nas folhas oscila durante o ano, e K e Mg variam mais do que N, P, Ca e S. O conteúdo de macronutrientes em folhas e cachos de pimenta-do-reino depende do estádio vegetativo da planta, e essa variação deve ser considerada no planejamento do manejo de adubação.

This research was funded by the Fundação de Amparo à Pesquisa e Inovação do Espírito Santo (FAPES, grant number 84320893), Conselho Nacional de Desenvolvimento Científico e Tecno-lógico, and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, Finance Code 001). Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This work aimed to evaluate the variability in the distribution of the root system among genotypes of C. canephora cv. Conilon and indicate management strategies for a more efficient mineral fertilization. Root distribution was evaluated in six genotypes. The experimental design was in randomized blocks with three replications. Soil monoliths measuring about 27 cm3 were collected at six different soil depths, at three row distances and nine distances of inter-row planting. The collections were carried out in one plant of each repetition. In total, 1296 samples were evaluated. The roots were washed, digitized and processed to quantify length density, volume, surface area and diameter. The distribution of the root system was characterized using semivariograms. It was observed that the highest concentration of roots occurred in the distances close to the irrigation drippers. There was variation in the distribution of the root system among the genotypes. However, in general, the root system is concentrated at a depth of 0 to 20 cm in the soil, at distances up to 50 cm in the planting row and up to 60 cm in inter-rows. Therefore, the greatest efficiency in nutritional management can be achieved by applying fertilizers within a radius of 50 cm around the plant. publishersversion published

This essay is a conceptual framework for testing the causal mechanisms of system degradation by metals in the mangrove ecosystem. The Fundao Dam collapse caused massive damage to the marine environment on the Southern Atlantic and Brazilian coast, reaching various kilometers from its origin, becoming a source of contamination. Along this Brazilian coast are vast mangrove areas with high biodiversity, different geomorphology, and distinct ecological functioning. These mangroves support fisheries' productivity in the Tropical South Atlantic, in connection with Abrolhos Reef. Brazil does not have a protocol to monitor environmental damage in this ecosystem, and we proposed to develop a way to identify the impact and quantify it. Along the estuaries, to assess the damage, the plots were demarked in three regions: the upper, middle, and lower estuary, and in both types of forest: fridge and basin. Samples of sediment and leaves were collected bi-monthly to evaluate metal concentrations, especially iron and manganese, the most abundant metals in Fundao Dam. The monitoring also evaluated the forest structure, dynamics of the crabs' population, and flora productivity. First-year monitoring identifies a high concentration of iron or manganese in the sediment above the NOAAs' recommendation in all the estuaries. The concentration of Fe and Mn in sediment varies seasonally in magnitude, concentration, and types of metals between estuaries, sectors, and forests. The behavior of biological indicators in the presence of metals (type and concentration) differed between fauna and flora species. The monitoring recognized that the tailings mining from Fundao Dam impacted all estuaries by different magnitudes and persistence. These differences are due to geomorphology diversity, climate, and oceanographic influences.

The growing requirement for micronutrients by increasingly more productive Robusta coffee genotypes and for the expansion of coffee plantations into low fertility soils has led to the need for better understanding of the micronutrient dynamics in Robusta coffee plants. The aim of the present study was to investigate micronutrient concentrations and their accumulation from flowering to fruit ripening, as well as micronutrient leaf concentrations throughout the year, in irrigated and non-irrigated Coffea canephora plants. Three-year-old Robusta coffee plants of genotype 02 were used. The fruit micronutrient accumulation curves for irrigated and non-irrigated Robusta coffee plants were best fitted by sigmoid functions. Irrigation resulted in higher micronutrient accumulation in fruits. Iron and boron were the micronutrients found in the highest amounts in fruits and leaves.

It is important to consider the nutritional demand among genotypes of the same species to achieve high yields. Thus, the objective of this study was to determine the concentration of nutrients in leaves, flowers, grains, and fruit straw in conilon coffee genotypes. The experiment was carried out under a randomized block design, with three replications and the evaluation of nine genotypes. Leaf collections were carried out every three months, from August 2019 to May 2020. Flowers were collected at flowering in July 2019 and fruits in June 2020, upon complete maturation of the genotypes. The materials were dried in an oven and sent for laboratory analysis to determine the nutritional content. Data were subjected to analysis of variance followed by a comparison of means and estimates of genetic parameters and clustering using the hierarchical method (UPGMA). The nutrients found in the highest concentrations in the evaluated plant organs were N and K for macronutrients and Fe for micronutrients. For the leaves, the concentrations of the main nutrients were high in the first and reduced in the last evaluated periods, possibly due to mobilization to the fruits. Considering all the plant tissues evaluated, the order of concentration of macronutrients and micronutrients was N > K > Ca > P = Mg = S and Fe > B > Mn > Cu > Zn, respectively. For a nutritional diagnosis, it is important to take comparisons of the genetic diversity and evaluation periods into consideration.

Coffea sp. is cultivated in large areas, using both conventional and organic management. However, information about the sustainability of these two management systems is still deficient. The objective of the present study was to evaluate the physical properties of soil cultivated with Conilon coffee (C. canephora) under organic and conventional management. Two areas cultivated with Conilon coffee (under organic and conventional management) and a fragment of Atlantic forest, used as a reference, were selected for the experiment. Soil granulometry, hydraulic conductivity, water retention curve, resistance to penetration, porosity, optimal hydric interval, and other physical characteristics were measured at depths of 0 to 10 and 10 to 20 cm. The data was submitted to multivariate and descriptive statistical analyses. Higher similarity was observed between the soil cultivated with Conilon coffee under organic management and the Atlantic forest soil. Soil resistance to penetration at 10, 30, 100, 500 and 1500 kPa, macro porosity, density and total porosity were the main physical properties that differentiated both management systems studied. The non-use of agricultural machinery and the addition of organic matter may be the main reasons for higher soil sustainability observed under organic management when compared with the conventional system.

As pastagens representam a base da alimentação dos bovinos no Brasil. Porém, os níveis de produtividade obtidos estão muito abaixo daqueles que poderiam ser alcançados com adoção do manejo adequado nas áreas de pastagens. Inúmeros fatores contribuem para esses resultados, com destaque para a baixa disponibilidade de nutrientes. Na literatura, pode-se observar, nas últimas décadas, o grande volume de trabalhos desenvolvidos avaliando a resposta de gramíneas forrageiras tropicais à adubação nitrogenada. No entanto, quando se avaliam as taxas de lotação das pastagens brasileiras, observa-se que essas informações geradas no campo da pesquisa não estão chegando até os produtores rurais.

EnglishThe extraction of nutrients from the soil by plants depends on soil fertility, plant management and plant production. The objec-tive of this study was to evaluate the effect of the application of sources and doses of nitrogen on macronutrient extraction by Panicum maximum cv. Mombaga. The experiment was conducted from 1 October 2011 to 14 April 2012 in the Federal Institute of Espirito Santo, Santa Teresa Campus. The experimental design was a randomised block design with three repetitions in a 3 X 6 factorial scheme, with three nitrogen fertilisers (urea, ammonium sulphate and calcium nitrate) and six nitrogen doses (0, 120, 240, 360, 480 and 600 kg ha-1). The established nitrogen doses were divided equally and applied every 28 days after the mombaga grass was cut, resulting in a total of seven applications during the 196-day experimental period. It was observed than nutrient extraction depends on forage plant production and was highest with the higher doses of nitrogen because of the greater dry matter production. The application of high doses of nitrogen in the form of calcium nitrate caused a reduced absorption of magnesium. Nitrogen fertilisation in pastures should be accompanied by the management of other nutrients to avoid nutritional imbalances or the depletion of soil fertility. EnglishLa extraccion de nutrientes depende de la fertilidad del suelo, de como las plantas son tratadas y de su produccion. El objetivo del presente trabajo es evaluar el efecto de la aplicacion de fuentes y dosis de nitrogeno sobre la extraccion de macronutrientes por el Panicum maximum cv. Mombaga. El experimento se llevo a cabo entre el 1 de octubre de 2011 y el 14 de abril de 2012, en el Instituto Federal do Espiritu Santo, Campus Santa Teresa. En la delineacion experimental se utilizaron bloques aleatorios, con tres repeticiones, en un esquema factorial 3 x 6: tres fertilizantes nitrogenados (urea, sulfato de amonio y nitrato de calcio) y seis dosis de nitrogeno (0, 120, 240, 360, 480 y 600 kg ha-1). Las dosis de nitrogeno establecidas se dividieron y se aplicaron de igual forma cada 28 dias, siempre despues del corte del capin mombaca, con un total de siete aplicaciones durante el periodo experimental de 196 dias. Se observo que la extraccion de nutrientes depende de la produccion del forraje, y es mayor para las dosis mas elevadas de nitrogeno, debido a la mayor produccion de materia seca. La aplicacion de elevadas dosis de nitrogeno, en la forma de nitrato de calcio, promovio la reduccion de la absorcion de magnesio. La fertilizacion nitrogenada en pastos debe estar acompanada por el manejo de los demas nutrientes, tratando de evitar el desequilibrio nutricional o el agotamiento de la fertilidad del suelo.

O objetivo deste trabalho foi estudar o tempo temporal e espacial da murcha do Fusarium em plantas de pimenta-do-reino. Como plantas foram avaliadas a cada dois meses durante um ano em nove areas plantadas com pimenta do reino localizado na regiao norte do estado do Espirito Santo, Brasil. Em cada area com 500 plantas em um campo de pimenta preta, faca uma localizacao de cada planta e avalie a incidencia de fusoes. A partir dessas praticas, foi usado um mapa acumulado de plantas afetadas na area selecionada. O progresso temporal das fusoes foi estudado por meio da contagem acumulada de doencas de plantas em funcao do tempo e ajuste desses dados nos modelos de crescimento biologico. O progresso espacial da doenca foi analisado pelo Indice de Dispersao e pelo ajuste da Lei de Taylor. Analisando o padrao de distribuicao espacial da doenca no campo, verificou-se um padrao predominantemente agregado. O maior periodo de evolucao da doenca em todas as areas plantadas foi observado a partir de novembro, coincidindo com a epoca da colheita, a epoca da alta influencia antropica.

Nitrogen influences numerous physiological and morphological traits of forage grasses, which ultimately interfere directly with production and forage quality. Aimed to study was to evaluate the production of dry matter and the number of tillers of Panicum maximum cv. Mombaça grown with different sources and levels of applied nitrogen. The experiment was conducted at the Federal Institute of the Espírito Santo, Campus of Santa Teresa. The experimental design consisted of a randomised block design with three replicates in a 3 x 6 factorial design and three nitrogenous fertilizers (urea, ammonium sulphate and calcium nitrate), which were applied at six different levels (0, 120, 240, 360, 480 and 600 kg ha-1) during the experimental period, for a total of 54 experimental units. Nitrogen levels were divided into seven applications, and the treatments were applied every 28 days, always after the forage was cut. The results show that Mombaça grass is responsive to nitrogen fertilization, and the response in terms of dry matter production and number of tillers for the same level of nitrogen varies depending on the nitrogen source used. Of the nitrogen sources, calcium nitrate had the best performance for the variables evaluated here. For this nitrogen source, the production of dry matter achieved at the maximum level of nitrogen was 18% and 36% higher than the dry matter achieved with the use of ammonium sulphate and urea, respectively.

Few studies have established protocols for measuring CO 2 emissions in the soil. In order to determine the time of day which best represents the average daily CO 2 emissions, the present study evaluated the variations in CO 2 emissions throughout the day and the relationship between these emissions and the soil moisture and temperature, in an attempt to standardize data collection in tropical soils. The study was carried out in an Atlantic forest fragment of the coastal tablelands, Brazil. A close relationship between CO 2 emission and soil temperature was observed, with CO 2 emissions decreasing as daytime temperatures increased. The soil moisture had no direct relation with the CO 2 emission, but was only related to the soil temperature. Two groups of CO 2 emissions were observed, forming between the sampling time from 09:00 a.m. to 10:00 p.m., and from 11:00 p.m. to 08:00 a.m. Due to the small difference found between the mean group formed between 09:00 a.m. and 10:00 p.m., which was ~ 8% when compared to the general average, and also the fact that CO 2 is easier to collect during this time, it is suggested that this period is the most suitable time to collect CO 2 in the field.

The number of days between anthesis and maturation of conilon coffee berries varies according to the genotype. Thus, it is believed that periods of greater nutrient demand for fruit formation also vary according to the genotype, directly influencing fertilizer management. The goal of this study was to establish accumulation curves for the micronutrients boron, copper, iron, manganese, and zinc in conilon coffee trees with different maturation cycles. The experiment was conducted in Nova Venécia, State of Espírito Santo, Brazil, during the reproductive cycle of the 2010/2011 crop year. Four coffee genotypes with different maturation cycles (early, intermediate, late, and super-late) were studied. A completely randomized experimental design was used with five replications. The treatments correspond to the accumulation of B, Cu, Fe, Mn, and Zn in the berries every 28 days in the period from flowering to harvest. The early, intermediate, and late genotypes accumulated Fe, Cu, and Mn in a similar manner, with sigmoid curves, whereas the super-late genotype accumulated these nutrients exponentially. Zn was accumulated by all four genotypes following a sigmoid curve. The early, intermediate, and late genotypes accumulated B linearly, whereas the super-late genotype accumulated B following a sigmoid curve. The maturation cycle of the genotype must be taken into account to apply the correct rate of micronutrient fertilization in coffee plantations.

Establishing the number of samples required to determine values of soil physical properties ultimately results in optimization of labor and allows better representation of such attributes. The objective of this study was to analyze the spatial variability of soil physical properties in a Conilon coffee field and propose a soil sampling method better attuned to conditions of the management system. The experiment was performed in a Conilon coffee field in Espírito Santo state, Brazil, under a 3.0 × 2.0 × 1.0 m (4,000 plants ha-1) double spacing design. An irregular grid, with dimensions of 107 × 95.7 m and 65 sampling points, was set up. Soil samples were collected from the 0.00-0.20 m depth from each sampling point. Data were analyzed under descriptive statistical and geostatistical methods. Using statistical parameters, the adequate number of samples for analyzing the attributes under study was established, which ranged from 1 to 11 sampling points. With the exception of particle density, all soil physical properties showed a spatial dependence structure best fitted to the spherical model. Establishment of the number of samples and spatial variability for the physical properties of soils may be useful in developing sampling strategies that minimize costs for farmers within a tolerable and predictable level of error.

O fornecimento de N tem sido importante meio para aumento da produtividade das gramíneas forrageiras tropicais no Brasil, pois, na maioria das áreas cultivadas, os teores desse nutriente no solo não atendem satisfatoriamente a necessidade das culturas. Avaliou-se o efeito da aplicação de diferentes fontes e doses de N sobre os atributos químicos de um Latossolo Amarelo e a produção do Panicum maximum cv. Mombaça. O experimento foi desenvolvido no Instituto Federal do Espírito Santo, campus Santa Teresa. O delineamento experimental utilizado foi em blocos casualizados, com três repetições, em esquema fatorial 3 × 6, sendo três fertilizantes nitrogenados (ureia, sulfato de amônio e nitrato de cálcio) e seis doses de N (0, 120, 240, 360, 480 e 600 kg ha-1), totalizando 54 unidades experimentais. As doses de N foram aplicadas a cada 28 dias, sempre após o corte da forrageira, totalizando sete aplicações durante o período experimental de 196 dias. Após o término do experimento, foram coletadas, com o auxílio de um trado holandês, amostras de solo na profundidade de 0-20 e 20-40 cm, para avaliar o efeito da aplicação dos tratamentos sobre os atributos químicos do solo nas diferentes profundidades. Os resultados experimentais evidenciaram que o sulfato de amônio apresentou elevado potencial de acidificação do solo. As alterações provocadas no pH do solo resultaram em alterações nos teores de Al trocável, na acidez potencial e na disponibilidade de P no solo. A aplicação de elevadas doses de N na forma de sulfato de amônio e nitrato de cálcio promoveu a lixiviação de bases, especialmente do K para a profundidade de 20-40 cm. Nitrogen supplementation has been an important means for increasing yield in tropical gramineous forage plants in Brazil because, in most growing areas, the levels of this nutrient in the soil do not adequately meet crop needs. We assessed the effect of different sources and application rates of N on the chemical properties of an Oxisol (Latossolo Amarelo) and the production of Panicum maximum cv. Mombaça. The experiment was carried out at the Instituto Federal do Espírito Santo (State of Espirito Santo, Brazil), Santa Teresa campus. A randomized block experimental design with three replications was used in a 3 × 6 factorial arrangement, with three N fertilizers (urea, ammonium sulfate, and calcium nitrate) and six N doses (0, 120, 240, 360, 480, and 600 kg ha-1), for a total of 54 experimental units. The N was applied every 28 days, always after cutting the forage, for a total of seven applications over the 196-day experimental period. At the end of the experiment, soil samples were collected at the depth of 0-20 and 20-40 cm with the aid of a Dutch auger to evaluate the effect of the application rate on the chemical properties of the soil at the different depths. The experimental results showed high potential for soil acidification from ammonium sulfate. The changes brought about in soil pH resulted in changes in exchangeable Al content, in potential acidity, and in P availability in the soil. The application of high rates of N in the form of ammonium sulfate and calcium nitrate led to leaching of bases, especially K at the depth of 20-40 cm.

Objetivou-se com o trabalho estudar a dinâmica de distribuição espaço-temporal da fusariose em pimenta-do-reino. Foram monitoradas quatro áreas de plantio, no município de São Mateus-ES, no período de dez/2015 a dez/2016. Realizaram-se seis avaliações da doença. As plantas foram avaliadas visualmente em busca dos sintomas típicos da doença. A presença ou ausência de sintomas, e a posição de cada planta, foram anotadas em planilhas obtendo-se o mapeamento da evolução da doença dentro das áreas. Com base nos mapas criados fez-se o estudo da distribuição espaço-temporal. A partir dos dados de incidência calculou-se a área abaixo da curva de progresso da doença (AACPD) e realizou-se o ajuste de modelos epidemiológicos. Para o estudo espacial utilizou-se a Lei de Taylor modificada, o Índice de Dispersão (ID) e a análise de dinâmica e estrutura de focos (ADEF). O modelo monomolecular foi o que melhor se ajustou à curva de progresso da fusariose. Observou-se que os resultados de ID variaram em cada área. A Lei de Taylor modificada indicou distribuição agregada somente em uma área. A ADEF demonstrou que com a evolução da doença ao longo do tempo os focos se tornavam maiores e em menor número.Palavras-chave: Piper nigrum; Fusarium solani f. sp. piperis; epidemiologia. SPATIO-TEMPORAL BEHAVIOR OF FUSARIOSIS IN BLACK PEPPER ABSTRACT: The objective of this study was to study the spatio-temporal dynamics of fusariosis in black pepper. Four planting areas were monitored in the municipality of São Mateus-ES, in the period from 10/2015 to 10 / 2016. Six classifieds of the disease were carried out. The plants were visually evaluated for the typical symptoms of the disease. The presence or absence of symptoms, and the position of each plant, were recorded on planets and the mapping of the evolution of the disease within the areas was obtained. Based on the sites visited, he studied the spatial-temporal distribution. From the calculation data, an area under the disease progress curve (AACPD) is calculated and adjusted for epidemiological models. For the spatial study we used a modified Taylor's Law, the Dispersion Index (ID) and a dynamics and foci structure analysis (ADEF). The monomolecular model was the one that best fit the progression curve of fusariosis. It was observed that the ID results varied in each area. The modified Taylor Law indicated the distribution of content in an area. ADEF demonstrated an evolution of the disease over time as the outbreaks became larger and smaller.Keywords: Piper nigrum; Fusarium solani f. sp. piperis; epidemiology.

The present study had as objective to determine mathematical equations to estimate the leaf area of pear cv. ‘Triunfo’ using linear dimensions of the leaves. For that, 300 healthy leaves of different sizes from each quadrant of plants from the small farm of Boa Vista located in the city of Montanha, at the northern side of the State of Espírito Santo, Brazil were used. The length (L) along the main vein was measured, along with the maximum width (W) of the leaf blade and observed leaf area (OLA), in addition to the product of the length and width (LW) of each leaf. From these measurements models of linear equations of first degree, quadratic and power were adjusted and their respective R2, using OLA as dependent variable and L, W and LW as independent variable. Based on the proposed equations, the data were validated obtaining the estimated leaf area (ELA). The mean of the ELA and OLA were compared by Student t test 5% probability. The mean error (E), the mean absolute error (MAE) and the root mean squared error (RMSE) was also used as validation criterion. The best equation model was defined based on the non-significant values from the comparison of means of ELA and OLA, E, MAE and RMSE values closer to zero and highest R2. The leaf area of pear cv. ‘Triunfo’ can be estimated by the equation ELA = -0.432338 + 0.712862(LW) non-destructively and with a high degree of precision.

The species Passiflora alata Curtis is one of the most important within this genus in Brazil , however , has some limitations in terms of productivity and fruit quality , which can be addressed through a program of selection followed by cloning techniques . The objective of this study was to evaluate the adventitious rooting of different native plants of P. alata , in the presence and absence of indole- 3 - butyric acid ( IBA) . The experiment was conducted in a kitchen with intermittent mist , temperature and humidity control system vegetation. The experimental design was completely randomized with four replicates , each using 16 stakes , 15 × 2 factorial arrangement of two factors : genotypes of P. alata ( 15 ) and IBA concentrations ( 0 and 2,000 mg L- 1 ) . With this work , it is concluded that there is no need of auxin for rooting cuttings of Passiflora alata genotypes studied . 11:15 genotypes were superior in all traits . The answer varies rizogenica as the genotype, that there are individuals more responsive than others .

Information on the spatial structure of soil physical and structural properties is needed to evaluate the soil quality. The purpose of this study was to investigate the spatial behavior of preconsolidation pressure and soil moisture in six transects, three selected along and three across coffee rows, at three different sites under different tillage management systems. The study was carried out on a farm, in Patrocinio, state of Minas Gerais, in the Southeast of Brazil (18 º 59 ' 15 '' S; 46 º 56 ' 47 '' W; 934 m asl). The soil type is a typic dystrophic Red Latosol (Acrustox) and consists of 780 g kg-1 clay; 110 g kg-1 silt and 110 g kg-1 sand, with an average slope of 3 %. Undisturbed soil cores were sampled at a depth of 0.10-0.13 m, at three different points within the coffee plantation: (a) from under the wheel track, where equipment used in farm operations passes; (b) in - between tracks and (c) under the coffee canopy. Six linear transects were established in the experimental area: three transects along and three across the coffee rows. This way, 161 samples were collected in the transect across the coffee rows, from the three locations, while 117 samples were collected in the direction along the row. The shortest sampling distance in the transect across the row was 4 m, and 0.5 m for the transect along the row. No clear patterns of the preconsolidation pressure values were observed in the 200 m transect. The results of the semivariograms for both variables indicated a high nugget value and short range for the studied parameters of all transects. A cyclic pattern of the parameters was observed for the across-rows transect. An inverse relationship between preconsolidation pressure and soil moisture was clearly observed in the samples from under the track, in both directions. Informações sobre a estrutura espacial das propriedades físicas e estruturais do solo são necessárias para avaliar a sua qualidade. O objetivo deste estudo foi investigar o comportamento espacial da pressão de preconsolidação e da umidade do solo em seis transectos: três ao longo e três perpendiculares às linhas de plantio do café, em três posições de amostragem com diferentes condições de tráfego. O experimento foi conduzido em uma fazenda localizada em Patrocínio, no Estado de Minas Gerais (latitude de 18 º 59 ' 15 '' S; longitude de 46 º 56 ' 47 '' W; 934 m acima do nível do mar). O solo, classificado como Latossolo Vermelho distrσfico típico, apresenta 780 g kg-1 de argila, 110 g kg-1 de silte e 110 g kg-1 de areia, com declividade média de 3 %. Amostras indeformadas foram coletadas na profundidade de 0,10-0,13 m, em três diferentes locais na lavoura cafeeira: na linha de tráfego, na entrelinha e sob a projeção da saia do cafeeiro. Foram dispostos seis transectos lineares na área experimental: três ao longo das linhas de plantio e três através das linhas de plantio. Assim, 161 amostras foram coletadas nos transectos através das linhas nos três locais estudados e 117 ao longo das linhas de plantio, em cada um dos locais avaliados. A menor distância entre os pontos amostrados foi de 4 m através dos transectos e de 0,5 m no sentido das linhas de plantio. Os valores de pressão de preconsolidação não exibiram padrões claros nos transectos. Os resultados dos semivariogramas para ambas as variáveis indicaram alto efeito pepita e curtos alcances em todas as situações estudadas e em todos os transectos. Um padrão cíclico dos parâmetros foi observado nos transectos através das linhas de plantio. A relação inversa entre a pressão de preconsolidação e a umidade do solo foi mais bem visualizada nas amostras coletadas na linha de tráfego, em ambas as direções avaliadas.

There is a growing demand for the estimation of load support capacity of soils on a larger scale in mitigating compaction and other degradation forms of agricultural soils. In this study, we examined the relationship between load support capacity and soil mineralogy, using four latosol (oxisol) types. Our results showed that soil color could be used as a first discriminator of load support capacity in latosols. Hematitic (reddish) latosols were observed to have lower load support capacity when compared to the goethitic (yellowish) soils. We observed that the clay mineralogy is associated with soil structure development and consequently with the load support capacity of the soil. Our study has laid a foundation for large-scale estimation of strength attributes in latosols indicated by their structure, which is associated with their quite stable and simple mineralogy.

Atualmente, a pressão de preconsolidação (sigmap) tem sido utilizada como uma ferramenta no estudo do processo de compactação do solo. O objetivo deste trabalho foi determinar a configuração e o número adequado de amostras para determinação da sigmap em um Latossolo Vermelho distroférrico, bem como caracterizar sua variabilidade e distribuição espacial, utilizando métodos da Estatística Clássica e da Geoestatística. O estudo foi realizado em uma área experimental, no município de Lavras-MG, sob plantio convencional nos últimos 30 anos, no qual são realizados anualmente uma aração e duas gradagens. A área experimental possui dimensões de 32 x 160 m (5.120 m²), com 68 pontos distanciados a 10 m no eixo X e a 8 m no eixo Y, mais seis transectos, sendo quatro com pontos distanciados de 2 m e dois com pontos distanciados de 1 m, visando detectar variações a pequenas distâncias. Foram coletadas 98 amostras indeformadas na profundidade de 0-3 cm, as quais foram submetidas ao ensaio de compressão uniaxial, para obtenção das sigmap. Por meio dos parâmetros da Estatística Clássica, estabeleceu-se o número adequado de amostras para determinar a sigmap, que foi igual a 10 pontos. A maior variabilidade foi obtida para a sigmap (CV 14,8 %), e a menor, para a umidade do solo (CV 12,0 %). Ambas as variáveis apresentaram distribuição normal, com modelo esférico ajustado, e moderada estrutura de dependência espacial, com alcance de 19,5 e 90,0 m, respectivamente. Em futuras amostragens para determinação da sigmap, em condições similares às da área estudada, sugere-se dispor os pontos de coleta com intervalo igual ao alcance de dependência espacial, visando associar menor esforço de amostragem com maior representatividade da área. Apesar de a razão de dependência espacial encontrada para as variáveis estudadas ter sido moderada, seu alcance deve ser considerado no planejamento de novas amostragens. A declividade do solo influenciou indiretamente os valores de sigmap. O mapeamento da área permitiu observar zonas de maior e menor suscetibilidade à compactação, possibilitando a tomada de decisão sobre onde começar a trafegar para evitar danos à estrutura do solo.

The soils in the state of Espirito Santo, Brazil (ES) display low natural fertility, which often limits the production of the crops due to the deficiency of some elements. However, they have a high potential for agricultural production when the chemical limitations which are present are overcome. The aim of this study was to describe the spatial variability of the macronutrients calcium (Ca), magnesium (Mg), phosphorus (P) and potassium (K) in a crop of conilon coffee (Coffea canephora Pierre) located in the rural area of the city of Sao Mateus, ES. The experiment was carried out on a crop, planted at a spacing of 1.8 x 1.0 m (5,555 plants ha-1). A rectangular grid of 61.6 x 20.0 m (1,232 m2) was considered, with 60 sampling points, spaced 5.6 m apart between rows and 5.0 m within each crop row. At each point in the sampling grid, soil samples were collected at a depth of 0.00-0.20 m. All the macronutrients under study displayed a strong spatial dependence. The greatest range of spatial dependence was observed for Mg (32.4 m) and the smallest for Ca (8.1 m). Study of the spatial variability of the chemical properties of the soil by geostatistics, using kriging, proved to be an important tool in understanding the spatial distribution of macronutrients in the soil, and may be crucial in aiding the decision making that helps to attend the nutritional requirements of the conilon coffee crop.

O conhecimento do padrão de distribuição espacial de um inseto permite concentrar o esforço amostral e de manejo nos locais onde se encontram as maiores densidades populacionais. Além disso, o comportamento espacial do inseto fornece informações sobre as condições no agroecossitema e a migração ou agregação da praga. Apesar da importância para o manejo de pragas, o conhecimento sobre a distribuição espacial de Hypothenemus hampei no café conilon possui raros relatos na literatura. Assim, objetivou-se no presente estudo determinar a variabilidade espacial da incidência de H. hampei no café conilon. Foi instalada uma malha irregular com 100 pontos em uma lavoura de alta produtividade, localizada em São Mateus, ES, safras 2011/2012 e 2012/2013. Avaliou-se após a coleta de amostras de frutos em cada ponto o número de frutos atacados pela praga por meio da verificação da perfuração característica nos frutos. Os dados foram submetidos à análise geostatística. Foi possível verificar a variabilidade de densidade no ataque da praga nos diferentes anos safra. Os semivariogramas referentes ao ataque do inseto ajustaram-se melhor ao modelo esférico e ao modelo exponencial, com índice de dependência espacial de 72 e 62%, respectivamente. Observou-se uma tendência de movimentação do ataque da praga de uma safra para outra a partir das bordas para o centro da lavoura.

O Sistema Integrado de Diagnose e Recomendação (DRIS), apesar de ser comumente utilizado na interpretação de análises foliares, pode ser empregado em análise química de solo, existindo potencial do uso da metodologia em solos cultivados com cafeeiros. Objetivou-se estabelecer faixas de suficiência e normas DRIS para solos cultivados com cafeeiro conilon na região Atlântica do Estado da Bahia. Coletaram-se 24 amostras de solo em 2012 e 2013, na profundidade de 0-20 cm, sendo quantificados os teores de matéria orgânica, Ca, Mg, K, P, S, Zn, B, Cu, Fe, Mn, saturação de bases e capacidade de troca catiônica a pH 7. Estabeleceram-se normas DRIS e faixas de suficiência para os nutrientes do solo, a partir de lavouras com produtividade, igual e superior a 100 sacas beneficiadas ha-1 de café conilon, sendo aplicáveis na recomendação de adubação da cultura na região. A maioria dos parâmetros estabelecidos apresentou discrepância em relação ao referencial teórico que se tem atualmente para o café conilon. Os resultados sugerem o desenvolvimento de normas regionais e específicas para a aplicação do método DRIS e faixas de suficiência no solo, para lavouras de café conilon.