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Barreiras, Brazil

Karsten J.,Colegiado de Agronomia | Chaves D.V.,State University of Southwest Bahia | Costa L.C.,Federal University of Paraiba | Ribeiro W.S.,Federal University of Vicosa | And 2 more authors.
Acta Horticulturae | Year: 2015

The bird of paradise is one of the main species of tropical flowers used as cut flower in Brazil and in many other parts of the world. In previous experiments, the lack of uniformity in the diameter among stems ready to be harvested was observed, which can lead to variations in the vase life. Therefore, the purpose of this study was to characterize the differences found in cut stems and florets. Stems with the first floret open were harvested and separated in three different diameters: thin (less than 10 mm), medium (between 10 and 12 mm) and thick (bigger than 12 mm of diameter). All stems were kept in individual vase containing distilled water, which was changed every 48 h to prevent growth of microorganisms. Half of the stems were uncut at the base of the stem and the other half was recut every 48 h to prevent xylem blockage. The number of open florets, longevity, length of the sepals and bracts, fresh mass, and absorption area at the base of the stem were determined. Thicker stems that had the base of the stem cut every 48 h showed a higher number of florets opened (2.3 florets) and longevity (8 days). Immediately after harvest, thicker stems had larger size of sepals, bracts and higher fresh mass and absorption area. Inflorescences of bird of paradise flower with stem diameters bigger than 12 mm, which were recut every 48 h showed better postharvest vase life performance than the inflorescences with thinner diameter.

Montanari R.,Federal University of Mato Grosso do Sul | Marques Junior J.,Sao Paulo State University | Campos M.C.C.,Colegiado de Agronomia | de Souza Z.M.,University of Campinas | Camargo L.A.,Sao Paulo State University
Revista Ciencia Agronomica | Year: 2010

Different surface land form expressed by the relief can cause variations in soil properties in different magnitudes, depending mainly on a specific location in the landscape. Therefore, the objective of this study was to make the mineralogical characterization of Oxisols in different relief forms in the region of Jaboticabal, SP. Three trenches were opened in the convex, linear and concave landforms, done morphological description of the soil horizons and collected soil samples for physical, chemical and mineralogical characterization. It was found that the oxidic mineralogy is dependent on the type of landform, with the dominance of goethite on the concave landform and hematite on the linear landform. The desferrific clay minerals exhibited dominance of gibbsite in the concave, compared to convex and linear landforms that were dominated by the kaolinitic mineralogy.

Campos M.C.C.,Colegiado de Agronomia | Ribeiro M.R.,Federal Rural University of Pernambuco | de Souza Junior V.S.,Federal Rural University of Pernambuco | Filho M.R.R.,Federal Rural University of Pernambuco | da Costa E.U.C.,Federal Rural University of Pernambuco
Revista Ciencia Agronomica | Year: 2010

Variations of soil properties are consequence of several factors such as: climate, parent material, vegetation and, particularly relief, which controls runoff and drainage, and has influence in the exposure of parent materials to the weathering action. The objective of this work was to study the influence of the slope segments on soil attributes of a topossenquence in the Manicoré region, AM. Twenty samples were collected in each of the several slope segments identified along a 3 km transect, from the top and toward the lower part of the topography. The slope segments and the sampling depths were: high top (0.0-0.19 and 0.37-0.60 m), medium slope (0.0-0.28 and 0.60-0.80 m); lower slope (0.0-0.15 and 0.42-0.71 m) and low top (0.0-0.15 and 0.20-0.40 m). The sampling depths were coincident with the surface and subsurface diagnostic horizons defined in the profile morphological description. Physical analysis involved particle size distribution, soil and particle density, total porosity and saturated hydraulic conductivity. In the chemical analysis pH in water and KCl, exchangeable cations, exchangeable Al, available P, H+Al, organic carbon were determined. The use of multivariate statistic techniques enabled the distinction of different soil geomorphic environments independent of the slope segments identifications. The relief variations contributed to the presence of dystrophic soils in the high top and eutrophic soils in the lower slope.

Pimentel M.S.,Federal University of Vale do Sao Francisco | Carvalho R.S.,Bahia State University | Martins L.M.V.,Bahia State University | da Silva A.V.L.,Colegiado de Agronomia
Revista Ciencia Agronomica | Year: 2011

The goal of this work was to evaluate the response of edaphic macrofauna, soil microbial biomass carbon, soil basal respiration, metabolic quotient and labile carbon of fumigated soil in a Fluvic Neosol. The experimental design was in randomized blocks, with five treatments (four green manure mix and one control) and four replications, and subsequent planting of melon (Cucumis melo L.) under semi-arid conditions in Juazeiro, Bahia State, Brazil, from August 2006 to August 2007. Soil samples were collected at a depth of 0-10 cm at 6 days before, and 117; 215 and 354 days after green manure mix planting. The results indicate that none of the attributes presented a significant difference for the treatments, but changed significantly in relation to the time of sample collection. The higher levels of soil microbial biomass carbon and labile carbon of fumigated soil were measured 117 days after planting. Soil microbial biomass carbon was inversely correlated with soil basal respiration and metabolic quotient, which increased as of 215 days after planting. At 354 days after planting, the edaphic macrofauna presented the highest density, richness, diversity and uniformity. Ants and beetles were most abundant in the areas studied.

Campos M.C.C.,Colegiado de Agronomia | Marques Junior J.,Sao Paulo State University | de Souza Z.M.,University of Campinas | Siqueira D.S.,Sao Paulo State University | Pereira G.T.,Sao Paulo State University
Revista Ciencia Agronomica | Year: 2012

The geomorphic surface concept allows interrelationship among various branches of soil sciences, such as geology, geomorphology and pedology. This association enhances the understanding of spatial soil distribution through landscape, pointing out the soil attributes behavior, which are mainly related to stratigraphy and relief forms. Therefore, this study aims to apply multivariate statistics to categorize geomorphic surfaces in sandstone - basalt lithosequence, so as to provide a basis for soil assessment in similar areas. The study area is located in Pereira Barreto County, SP, Brazil. An area of 530 hectare was selected, where three geomorphic surfaces (I, II and III) were located and mapped. In this area, 134 soil samples were collected at depths of 0.0-0.2 m and 0.8-1.0 m below ground surface. Sand, silt and clay contents were determined, pH in CaCl2 solution, OM, P, Ca, Mg, K, Al and H+Al contents were also evaluated. Based on the results, univariate, multivariate analysis of variance, cluster and principal-component analysis were performed in order to compare the three geomorphic surfaces. The univariate statistical analysis of soil attributes was not efficient enough to categorize the three geomorphic surfaces. By using the physical and chemical soil properties, the multivariate statistical techniques enabled the differentiation of the three groups of soil natural bodies which were equivalent to the same three mapped geomorphic surfaces (GS). These results are interestingin order to demonstrate the feasibility of the numerical classification use on geomorphic surfaces to assist the soil mapping.

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