Time filter

Source Type

Cassilândia, Brazil

Abrantes F.L.,Sao Paulo State University | Kulczynski S.M.,Federal University of Santa Maria | Soratto R.P.,Sao Paulo State University | Barbosa M.M.M.,UEMS
Revista Brasileira de Sementes | Year: 2010

Nitrogen can influence the seed quality of several crops and its effects vary with the environmental conditions and the plant stage when the nitrogen is applied. However, little is known of the influence of nitrogen fertilization on seed quality in proso millet (Panicum miliaceum L.). The objective of this study was to evaluate the effect of dosages and times of nitrogen top-dressing applications on the physiological and sanitary quality of proso millet, cv. AL Tibagi, seeds grown under field conditions. Seeds were produced between December, 2005 and February, 2006 and laboratory evaluations between March and August, 2006. A completely randomized block design in a 4×2 factorial was used, with a combination of four dosages (0, 30, 60, and 120 kg ha-1 of N) and two application times (14 and 28 days after emergence) of nitrogen fertilizer (urea) in top-dressing with four replications. Nitrogen application increased seed vigor, expressed by the tests of accelerated ageing and field emergence. Source

Schiavo J.A.,State University of Mato Grosso do Sul | Pereira M.G.,Federal Rural University of Rio de Janeiro | de Miranda L.P.M.,Sao Paulo State University | Neto A.H.D.,UEMS | Fontana A.,Engenheiro Agronomo do INCRA
Revista Brasileira de Ciencia do Solo | Year: 2010

The Aquidauana geological formation consists of a set of up to 500 m thick sediments predominantly composed of sandstone with fine to medium grain size, interspersed with sandy conglomerates. In this environment, the topography is one of the main conditioning factors of the formation of different soil types in the landscape. The objective of this study was to characterize and classify soils developed from these sandstones. Four soils profiles along a representative toposequence of gentle slopes were sampled and studied. The profiles were located on the shoulder (P1), backslope (P2), footslope (P3) and toeslope (P4). The soil profiles were morphologically described and physical and chemical properties of their horizons evaluated. The sand fraction was predominant in all profiles (> 680 g kg-1), with textures ranging from sandy loam (P4) to clay sandy loam. The water pH values ranged from 4.2 to 6.5. The cation exchange capacity values ranged from 1.6 cmolc kg-1(in P4) to 10.3 cmolc kg-1 (in P2), with a predominance of hydrogen ions in P1 and P4, and calcium in profile P2 and P3. The P1 and P4 pedons were dystrophic, whereas in P2 and P3, a high base saturation status evidenced an eutrophic character. Except in P2, the profiles presented low activity clays. In all soil profiles the morphological, physical, chemical and mineralogical properties were conditioned by the parent material and relief, demonstrating the influence of these factors on the pedogenesis. Source

Pereira M.G.,Federal Rural University of Rio de Janeiro | Schiavo J.A.,State University of Mato Grosso do Sul | Fontana A.,Embrapa Solos | Neto A.H.D.,UEMS | de Miranda L.P.M.,Sao Paulo State University
Revista Brasileira de Ciencia do Solo | Year: 2013

The soils in the Serra da Bodoquena, a mountain chain in the state of Mato Grosso do Sul, Brazil, have peculiar features that differ from other regions of the Cerrado-Pantanal biome. This study aims to characterize soils formed on limestone, based on the physical, chemical and mineralogical properties and organic matter. A toposequence on limestone was selected and profile pits were opened on the summit (P1), backslope (P2), footslope (P3) and toeslope (P4 and P5). The profiles were morphologically described and physical, chemical and mineralogical analyses were carried out in all horizons. According to the Brazilian System of Soil Classification (SiBCS), the studied soils were classified as: (P1) Organossolo Fólico Sáprico lítico - OOs (Litic Ustifolist); (P2) Chernossolo Háplico Órtico típico - MXo (Typic Haplustoll); (P3) Chernossolo Argilúvico Órtico típico - MTo (Typic Haplustoll); (P4) Gleissolo Melânico Carbonático chernossólico - GMk1 (Typic Epiaquoll); and (P5) Gleissolo Melânico Carbonático organossólico - GMk2 (Terric Haplosaprist). The color of all studied profiles was dark in the surface horizons, and reddish or grayish in deeper layers, according to the drainage conditions. Base saturation was high in all layers, with calcium as dominant cation in the exchangeable complex. Humin was the dominant organic carbon fraction of the studied soils. A mineralogical analysis showed the presence of calcite in the sand fraction in the soil profiles GMK1 and GMk2 and kaolinite, illite and montmorillonite in the clay fraction of all soils. The occurrence of Ustifolist in non-mountainous environments, different from the characterization by the SiBCS, suggests a greater range of possible environmental conditions for the occurrence of this suborder. Source

Souza A.C.,UEMS | Aristone F.,Federal University of Mato Grosso | Capitanio R.A.,Federal University of Mato Grosso | De Paula M.H.,Federal University of Mato Grosso
Sensors and Actuators, B: Chemical | Year: 2016

In this letter we exhibit a series of results obtained using the technique of photothermal spectroscopy to determine the concentration of water in water-ethanol solutions. At low concentrations water is completely miscible with ethanol and particularly difficult to separate into parts in order to determine the complementary amount of each component, especially when considering measurements for such quantification in large scale. Ethanol has been promoted to a special class of product in the last decade due to its use as a renewable fuel for cars. However, it is of extreme importance to control the amount of water mixed in ethanol in order to avoid all sorts of erroneous possibilities regarding the indications for best performance of the engines. The results presented in this paper indicate the possibility of a new systematic setup to determine accurately the water content on water-ethanol solutions using photo-thermal techniques. © 2015 Published by Elsevier B.V. Source

This study aimed to evaluate different proportions of organic compost and soil as a substrate for the guavira emergence and seedling formation under different protected environments, in the high Pantanal region of the state of Mato Grosso do Sul. The seeds were placed in polyethylene bags (15 × 25 centimeters) filled with four percentages of organic compost (0%, 20%, 80%, and 100% of total volume) mixed with soil. These substrates were tested in agro-nurseries covered with black screen and 50% thermo-reflecting shade cloths. The substrate with 20% soil and 80% organic compost and the black screen shade cloth promote the best performance in the seedling production. Source

Discover hidden collaborations