Embrapa Brazilian Agricultural Research Corporation

Pelotas RS, Brazil

Embrapa Brazilian Agricultural Research Corporation

Pelotas RS, Brazil
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Arrouays D.,French National Institute for Agricultural Research | Grundy M.G.,CSIRO | Hartemink A.E.,University of Wisconsin - Madison | Hempel J.W.,Natural Resources Conservation Service | And 13 more authors.
Advances in Agronomy | Year: 2014

Soil scientists are being challenged to provide assessments of soil condition from local through to global scales. A particular issue is the need for estimates of the stores and fluxes in soils of water, carbon, nutrients, and solutes. This review outlines progress in the development and testing of GlobalSoilMap-a digital soil map that aims to provide a fine-resolution global grid of soil functional properties with estimates of their associated uncertainties. A range of methods can be used to generate the fine-resolution spatial estimates depending on the availability of existing soil surveys, environmental data, and point observations. The system has an explicit geometry for estimating point and block estimates of soil properties continuously down the soil profile. This geometry is necessary to ensure mass balance when stores and fluxes are computed. It also overcomes some limitations with existing systems for characterizing soil variation with depth. GlobalSoilMap has been designed to enable delivery of soil data via Web services. This review provides an overview of the system's technical specifications including the minimum data set. Examples from contrasting countries and environments are then presented to demonstrate the robustness of the technical specifications. GlobalSoilMap provides the means for supplying soil information in a format and resolution compatible with other fundamental data sets from remote sensing, terrain analysis, and other systems for mapping, monitoring, and forecasting biophysical processes. The initial research phase of the core project is nearing completion and attention is now shifting toward establishing the institutional and governance arrangements necessary to complete a full global coverage and maintaining the operational version of the GlobalSoilMap. This will be a grand and rewarding challenge for the soil science profession in the coming years. © 2014 Elsevier Inc.

Placido C.G.,Ifam Instituto Federal Of Educacao | Moreira A.,EMBRAPA Brazilian Agricultural Research Corporation | Moraes L.A.C.,EMBRAPA Brazilian Agricultural Research Corporation
Communications in Soil Science and Plant Analysis | Year: 2015

In agriculture there is a tendency to reduce spacing between plant rows, both for perennial and annual plants. Yield gains have been associated with the use of this technique. However, in the case of perennial plants, this technique was found to reduce productivity in older orchards because of the greater competition between plants caused by the increased volume of the crown and root system, resulting in lower photosynthetic efficiency, increased infestation with fungal diseases, and greater competition in nutrient uptake. In addition to yield, efficient management should consider soil fertility, nutritional status, and the growth of the guarana variety. The present study aimed to assess the effects of spacing and plant density on grain yield, soil fertility, and nutritional status of two guarana varieties (BRS Amazonas and BRS Maués). The plant density studied were 625 (4 m × 4 m), 833 (4 m × 3 m), 1,111 (3 m × 3 m), 1,666 (3 m × 2 m), 2,500 (2 m × 2 m), and 5,000 (2 m × 1 m) plants per hectare distributed in randomized block design with three replicates. The high plant density has significantly increased grain yield in the guarana varieties, with changes in launch number, trunk diameter, and crown diameter. Regarding macronutrients, in the average of the varieties, the mean foliar concentration had the following sequence: nitrogen (N) > potassium (K) > calcium (Ca) > phosphorus (P) > sulfur (S) > magnesium (Mg), whereas for micronutrients it was manganese (Mn) > iron (Fe) > boron (B) > zinc (Zn) > copper (Cu). The differences in the foliar concentrations of the varieties and in soil fertility are important tools for the selection of materials with better capacity of uptake and/or translocation of nutrients, resulting in greater grain yield. Copyright © Taylor & Francis Group, LLC.

PubMed | EMBRAPA Brazilian Agricultural Research Corporation, EMBRAPA Dairy Cattle Brazilian Agricultural Research Corporation, Federal University of Juiz de fora and French National Institute for Agricultural Research
Type: Journal Article | Journal: Microbial ecology | Year: 2016

Anaerobic digestion is an alternative method for the treatment of animal manure and wastewater. The anaerobic bioconversion of biomass requires a multi-step biological process, including microorganisms with distinct roles. The diversity and composition of microbial structure in pilot-scale anaerobic digestion operating at ambient temperature in Brazil were studied. Influence of the seasonal and temporal patterns on bacterial and archaeal communities were assessed by studying the variations in density, dynamic and diversity and structure. The average daily biogas produced in the summer and winter months was 18.7 and 16 L day(-1), respectively, and there was no difference in the average methane yield. Quantitative PCR analysis revealed that no differences in abundances and dynamics were found for bacterial communities and the total number of Archaea in different seasons. Analysis of bacterial clone libraries revealed a predominance of Firmicutes (54.5 %/summer and 46.7 %/winter) and Bacteroidetes (31.4 %/summer and 44.4 %/winter). Within the Archaea, the phylum Euryarchaeota was predominant in both digesters. Phylogenetic distribution showed changes in percentage between the phyla identified, but no alterations were recorded in the quality and amount of produced methane or community dynamics. The results may suggest that redundancy of microbial groups may have occurred, pointing to a more complex microbial community in the ecosystem related to this ambient temperature system.

Parfitt J.M.B.,Embrapa Brazilian Agricultural Research Corporation | Timm L.C.,Campus Universitario | Reichardt K.,University of Sao Paulo | Pauletto E.A.,Federal University of Pelotas
Revista Brasileira de Ciencia do Solo | Year: 2014

The practice of land leveling alters the soil surface to create a uniform slope to improve land conditions for the application of all agricultural practices. The aims of this study were to evaluate the impacts of land leveling through the magnitudes, variances and spatial distributions of selected soil physical properties of a lowland area in the State of Rio Grande do Sul, Brazil; the relationships between the magnitude of cuts and/or fills and soil physical properties after the leveling process; and evaluation of the effect of leveling on the spatial distribution of the top of the B horizon in relation to the soil surface. In the 0-0.20 m layer, a 100-point georeferenced grid covering two taxonomic soil classes was used in assessment of the following soil properties: soil particle density (Pd) and bulk density (Bd); total porosity (Tp), macroporosity (Macro) and microporosity (Micro); available water capacity (AWC); sand, silt, clay, and dispersed clay in water (Disp clay) contents; electrical conductivity (EC); and weighted average diameter of aggregates (WAD). Soil depth to the top of the B horizon was also measured before leveling. The overall effect of leveling on selected soil physical properties was evaluated by paired "t" tests. The effect on the variability of each property was evaluated through the homogeneity of variance test. The thematic maps constructed by kriging or by the inverse of the square of the distances were visually analyzed to evaluate the effect of leveling on the spatial distribution of the properties and of the top of the B horizon in relation to the soil surface. Linear regression models were fitted with the aim of evaluating the relationship between soil properties and the magnitude of cuts and fills. Leveling altered the mean value of several soil properties and the agronomic effect was negative. The mean values of Bd and Disp clay increased and Tp, Macro and Micro, WAD, AWC and EC decreased. Spatial distributions of all soil physical properties changed as a result of leveling and its effect on all soil physical properties occurred in the whole area and not specifically in the cutting or filling areas. In future designs of leveling, we recommend overlaying a cut/fill map on the map of soil depth to the top of the B horizon in order to minimize areas with shallow surface soil after leveling.

Macedo A.N.,University of Sao Paulo | Brondi S.H.G.,Embrapa Brazilian Agricultural Research Corporation | Vieira E.M.,University of Sao Paulo
Food Analytical Methods | Year: 2013

Most studies to determine sulfonamide residues in milk samples have used solid-phase extraction as the sample preparation technique. However, the quick, easy, cheap, effective, rugged, and safe (QuEChERS) method, introduced in 2003, has been used in the extraction of various compounds in food matrices. This study aimed to evaluate two sample preparation techniques: solid-phase extraction and QuEChERS, for chromatographic analysis of sulfonamides (sulfathiazole, sulfamethazine, and sulfadimethoxine) in bovine milk. The chromatographic parameters and the QuEChERS extraction procedure were developed by using different experimental designs, obtaining good peak resolution, recovery, precision, accuracy, linearity, selectivity, and limits of detection and quantification. In contrast, using solid-phase extraction, acceptable recoveries and selectivity were not achieved, despite the number of articles published that have applied this sample preparation technique for sulfonamide analysis. As a result of the experiments performed, probably sulfonamides are retained together with other components of the matrix in the sample pretreatment step (prior to its addition in the cartridge containing solid phase), which is an important part of solid-phase extraction with raw whole milk. Therefore, QuEChERS is a better method than solid-phase extraction for the analysis of sulfonamide residues in milk. Validation tests demonstrated that the method is appropriate, within the maximum residue limit (0.1 mg kg-1). Moreover, it was possible to use a lower amount of solvent compared with previously published articles (6 mL against 10 or 15 mL). © 2013 Springer Science+Business Media New York.

Porto A.J.V.,University of Sao Paulo | Inamasu R.Y.,EMBRAPA Brazilian Agricultural Research Corporation
Journal of the Brazilian Society of Mechanical Sciences and Engineering | Year: 2010

A current trend in distributed control systems is the application of communication network technologies such as CAN - Controller Area Network. A recent utilization approach of these technologies is the networked control systems (NCS). The fundamental challenges in the development of NCS are the analysis of the network delay effects and the prediction of the timing behavior of the distributed control system. The common parameters that impact the performance of NCS include response time, network utilization and network delays induced by the communication of messages between the devices. In addition, the performance of a NCS is highly dependent on these messages sampling times. A significant emphasis has been put on development and application of methodologies to handle the network delay effect in these systems and improve their performances. This paper presents a detailed timing analysis and a mathematical model to calculate these network delays in CAN-based networks. With the results of this model, the application of a methodology is proposed to minimize the effects of these delays and to achieve the optimization (network operation and utilization) of a CAN-based network. A case study of a CAN-based distributed control system in a mobile robot is described to demonstrate the application of the optimization methodology and the utilization of the CAN mathematical model systemized. © 2010 by ABCM.

Paiva S.R.,Embrapa Brazilian Agricultural Research Corporation | McManus C.M.,University of Brasilia | Blackburn H.,U.S. Department of Agriculture
Livestock Science | Year: 2016

For the past 20 years countries have initiated programs to sustainably conserve farm animal genetic resources. At the same time the growing need for increased animal productivity has emerged. Viewing gene banks and in vivo conservation in the context of food security, climate change, and product demand suggests the need for a more efficient use of these mechanisms to support sustainable productivity. Some advances have been made in developing and implementing in-vivo conservation programs, but those efforts appear to be predicated upon various types of government subsidies, which are subject, to policy changes. Given the in-vivo situation, it is suggested conservation efforts shift toward gene banks as the primary conservation mechanism. Globally, national gene banking efforts have increased and they have the capacity and potential to become more dynamic, incorporate different biological materials and facilitate increased use of genetic diversity. The next steps for gene banks are to better utilize information systems to integrate and store data from genetic/genomic assessments, cryopreservation, phenotypes and environmental conditions. These types of benefits plus the reduced conservation costs gene banks can speed the rate of conserving breeds while freeing the livestock sector to increase productivity with the breeds of their choosing. © 2016

Andreazza R.,Federal University of Rio Grande do Sul | Andreazza R.,Federal University of Pelotas | Bortolon L.,EMBRAPA Brazilian Agricultural Research Corporation | Pieniz S.,Federal University of Rio Grande do Sul | Camargo F.A.O.,Federal University of Rio Grande do Sul
Pedosphere | Year: 2013

Copper (Cu) contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i) to evaluate the phytoremediation capacity of the high-yielding bioenergy plant castor bean (Ricinus communis L.) in vineyard soils (Inceptisol and Mollisol) contaminated with Cu and a Cu mining waste; ii) to characterize the castor bean as a Cu phytoremediation plant; and iii) to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots' fresh mass and shoots' dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients (such as N, P, and Mg) during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5 900, 3 052 and 2 805 g ha-1, respectively. In addition, the castor bean's elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil. © 2013 Soil Science Society of China.

Scagliusi S.M.,EMBRAPA Brazilian Agricultural Research Corporation
Australian Journal of Crop Science | Year: 2014

The objective of this study was to establish an isolated microspore culture (IMC) protocol in wheat (Triticum aestivum L.) for use in genetic studies and to evaluate its potential for routine use in the Brazilian Wheat Breeding Program at Embrapa Wheat. Important steps of the method were identified and plant physiology of microspore mother plants and ovary co-culture were considered as key factors for effective establishment. Three Brazilian wheat genotypes were tested (Toropi, BRS 194 and F1 wheat cross 020037 × 020062), and two other genotypes were used as controls (Bobwhite and Fielder). Spikes containing uninucleated microspores were subjected to cold pretreatment (4°C) for 21 days in the dark. Number of embryos, green and albino plants were recorded for each genotype. The method was successfully established, and several fertile green plants were produced by using tissue culture and responsive controls. However, the results greatly differed among Brazilian wheat genotypes, suggesting a strong genotype-dependent effect. Microspore induction medium alone did not promote embryogenesis; ovary co-culture was a necessary step for embryo development and green plant formation, for all genotypes. The F1 wheat cross (020037 × 020062) produced a total of 85 green plants (out of 108 spikes), 64% of which were spontaneous diploids. BRS 194 produced many embryos, exhibiting a good androgenic response, but only a few grew into green plants. Toropi behaved as a recalcitrant genotype, and zero plants were produced. To our knowledge, this is the first report on wheat IMC from Brazilian genotypes resulting in androgenic embryogenesis and plant regeneration.

PubMed | EMBRAPA Brazilian Agricultural Research Corporation
Type: Journal Article | Journal: International journal of biometeorology | Year: 2014

The objective of this work was to develop and evaluate agrometeorological models to simulate the production of Guineagrass. For this purpose, we used forage yield from 54 growing periods between December 2004-January 2007 and April 2010-March 2012 in irrigated and non-irrigated pastures in So Carlos, So Paulo state, Brazil (latitude 215742 S, longitude 475028 W and altitude 860m). Initially we performed linear regressions between the agrometeorological variables and the average dry matter accumulation rate for irrigated conditions. Then we determined the effect of soil water availability on the relative forage yield considering irrigated and non-irrigated pastures, by means of segmented linear regression among water balance and relative production variables (dry matter accumulation rates with and without irrigation). The models generated were evaluated with independent data related to 21 growing periods without irrigation in the same location, from eight growing periods in 2000 and 13 growing periods between December 2004-January 2007 and April 2010-March 2012. The results obtained show the satisfactory predictive capacity of the agrometeorological models under irrigated conditions based on univariate regression (mean temperature, minimum temperature and potential evapotranspiration or degreedays) or multivariate regression. The response of irrigation on production was well correlated with the climatological water balance variables (ratio between actual and potential evapotranspiration or between actual and maximum soil water storage). The models that performed best for estimating Guineagrass yield without irrigation were based on minimum temperature corrected by relative soil water storage, determined by the ratio between the actual soil water storage and the soil water holding capacity.irrigation in the same location, in 2000, 2010 and 2011. The results obtained show the satisfactory predictive capacity of the agrometeorological models under irrigated conditions based on univariate regression (mean temperature, potential evapotranspiration or degree-days) or multivariate regression. The response of irrigation on production was well correlated with the climatological water balance variables (ratio between actual and potential evapotranspiration or between actual and maximum soil water storage). The models that performed best for estimating Guineagrass yield without irrigation were based on degree-days corrected by the water deficit factor.

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