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Caruaru, Brazil

Reis L.S.,CECA | de Azevedo C.A.V.,Bairro Universitario | Albuquerque A.W.,CECA | Junior J.F.S.,Sao Paulo State University
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013

The tomato cultivation in the greenhouse has been expanded in the last years, mainly, in the South and Southeast regions of Brazil, whose purpose is to improve the productivity and the quality of the agricultural products, offering regularity in the production. The present study aimed to determine, along the crop cycle, the relationship between the leaf area index and the productivity, and at the end of the cycle, the components of production of the tomato in the greenhouse. The models were generated through polynomial equations of 1st and 2nd order, having as independent variable the number of days after the transplanting. It was verified that it is possible to determine, in the greenhouse, through mathematical models, the leaf area index of the tomato crop considering the days after the transplanting. Basing on values of leaf area index, the productivity of the crop and the period of the maximum productivity can be determined, aiding the farmers to determine the best sowing and transplanting time of the tomato crop.

Barreto A.N.,Embrapa Algodao | do Nascimento J.J.V.R.,DAIC IFPE | de Medeiros E.P.,Embrapa Algodao | da Nobrega J.A.,Bairro Universitario | Bezerra J.R.C.,Embrapa Algodao
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013

Agricultural use of wastewater is an alternative to increase water availability, especially in semiarid regions. However, it may cause undesirable chemical changes in the soil. The aim of this study was to evaluate the influence of wastewater irrigation and castor bean (Ricinus communis L.) cultivation on the chemical attributes of a Fluvic Neosol. The experimental design was in a randomized block, in split-plot scheme, where the main plots were represented by the treatments of irrigation water and castor bean cultivation, and the subplots were the soil layers, with three replications. The treatments were T1 - wastewater irrigation + castor bean cultivation; T2 - mixture of supply water and wastewater (1:1 ratio) + castor bean cultivation; T3 - supply water irrigation + castor bean cultivation; and T4 - wastewater application, without castor bean cultivation. The depths of soil layers were 0-10, 10-20, 20-30, 30-40, and 40-50 cm. At the end of study, the content of phosphorus, calcium, potassium, and organic matter increased mainly in the upper layers, and sodium increased in the deeper layers in the wastewater treatments, in comparison to the supply water irrigation. In T4, the disposal of wastewater increased the concentration of magnesium. The pH values, iron and zinc concentration did not statistically differ in the treatments.

Corgosinho P.H.C.,Bairro Universitario | Corgosinho P.H.C.,University Estadual Of Minas Gerais
Journal of Natural History | Year: 2012

A new genus of Nannopodidae is described. Talpacoxa brandini gen. et sp. nov. is a typical sand-dwelling species with modified burrowing first legs. The new genus can be diagnosed by leg 1 transformed into a burrowing structure; coxa hypertrophied, longer than the exopod and the endopod, with a well-developed crista, downwardly extended, with a bifid tip; exopod one-segmented, strong, rectangular, ornamented with various cuneiform spinules; endopod two-segmented, second endopodal segment with two distal elements; intercoxal plate well developed, longer than the exopod and the endopod. Leg two to leg four reduced, with two-segmented exopod and one-segmented endopod; limbs laterally displaced with no trace of intercoxal plate. Leg five exopod one-segmented; intercoxal plate reduced. The new genus is tentatively included within Nannopodidae because of some putative synapomorphies shared with the genera Rosacletodes, Huntemannia, Laophontisochra and Acuticoxa. © 2012 Copyright Taylor and Francis Group, LLC.

Manfroi J.,Museu de Ciencias Naturais | Jasper A.,Bairro Universitario | Guerra-Sommer M.,Federal University of Rio Grande do Sul | Uhl D.,University of Tubingen
Revista Brasileira de Paleontologia | Year: 2012

In the modern flora, lycophytes are restricted to a few herbaceous forms. The fossil record of this group is significantly larger, with numerous herbaceous, but also arborescent representatives, the latter mostly reported from late Paleozoic biomes. An association of compressed caulinar fragments of horizontally layered, sub-arborescent lycophytes (preserved as fossil casts) coming from a clastic level which overlies the Bonito coal seam in the Bonito I mine in the Santa Catarina coalfield (Santa Catarina state, Brazil) is analyzed in this paper. The material was identified as Brasilodendron pedroanum (Carruthers) Chaloner, Leistikow & Hill, a taxon that has been described from several outcrops in the coal-bearing interval of the Paraná Basin (Sakmarian/Artinskian). The present study supports the interpretation that sub-arborescent lycophyte plants showing the Brasilodendron leaf-cushion type were an important component of the coastal peat forming paleofloristic associations during the Early Permian (Cisuralian) in the Paraná Basin and were important contributors to the original biomass of coals. © 2012 by the Sociedade Brasileira de Paleontologia.

Queiroz A.J.M.,Bairro Universitario | Dantas H.J.,Bairro Universitario | De Figueiredo R.M.F.,Bairro Universitario | Melo K.D.S.,Federal University of Campina Grande
Engenharia Agricola | Year: 2011

Dryers heated by solar energy have been constructed and used in drying whole and half jack fruit almonds. The samples were dried during the day in direct sun and in the conventional solar dryer prepared for this purpose. Another piece of equipment was built for reception and accumulation of sun energy in a body of water, which was used as a heat source for night drying. The drying with the sun energy was compared with artificial drying. The jack fruit almonds were dried whole, half, with pellicle and without it. The storage of solar energy in water was technically viable for use in night drying. The drying by combining solar dryers in the day and night periods were completed in approximately 35 hours, and were equivalent to artificial drying between 40°C and 70°C. Almond cut in half and the pellicle removed reduced the drying time.

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