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Correa P.C.,Federal University of Vicosa | Botelho F.M.,UFMT | Botelho S.C.C.,Embrapa Agrossilvipastoril | Goneli A.L.D.,UFGD
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The objectives of this study were to evaluate and to model the isotherms curves obtained by adsorption and desorption processes for the fruits of ripe (cherries) coffee (Coffea canephora), for different psychrometric conditions of the air. For all sorption processes, different conditions of temperature (between 10 and 50 °C) and relative humidity (between 10 and 95%) were used, until the product reached its equilibrium moisture content with the air condition specified. For experimental data of sorption, different mathematical models often use to represent hygroscopicity of agricultural products were adjusted. It was verified that the equilibrium moisture content of the fruits of coffee increased with relative humidity for a given temperature and decreased with increasing temperature for a given relative humidity. The hysteresis, regardless of temperature, was more pronounced for relative humidity of the air between 65 and 75%. The Sigma-Copace model was the best in describing hygroscopicity of the fruits of coffee both in desorption and adsorption. © 2014, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved. Source

It was evaluated the development of "Baru" seedlings (DipteryxalataVog.) in pots under three levels of shading and four textural classes, from March to october 2010, in Campo Grande-MS. Treatments consisted of 0%, 30% and 50% levels of shade and sandy, medium clay and heavy clay soil. The experimental design was randomized blocks in split plots with repeated measures. It was used three replicates of ten plants per plot. The shading levels corresponded to the treatments and the different textural classes to the subplot. Plant height, leaf number and stem diameter were evaluated 15 days after emergence (DAE) to 195 DAE. Survival rate, leaf area and dry mass of the leaf, the stem and the roots were also estimated at 195 DAE. Higher values were observed in height and leaf area under shading condition. Plant height was 32.09 cm and 31.21 cm plant-1, leaf area was 639.24 cm 2 and 580.49 cm2 for 50% and 30% shade levels respectively. In clay soil the values were higher in most traits followed by soil with loamy soil. The highest yield of dry mass of leaf was in the clayey soil with an average of 7.28 g plant-1.The percentage of seedling survival in sandy soil was lower than in the others. There was an interaction between levels of shading and texture classes of soil on dry mass of the roots which was higher (1.43 g kg-1 soil) on the loamy soil at 50% shading. "Baru" seedlings reached measurements of height and diameter suitable for all levels of shading and textural classes. Source

This paper reports an occurrence of Meloidogyne enterolobii (syn. M. mayaguensis) in the State of Mato Grosso do Sul, on guava (Psidium guajava), cv. Novo Milênio. The nematode was characterized and identified using esterase (Est) isozyme phenotype (Est M2, Rm: 0.7 e 0.9). Source

The removal of the original vegetation and deployment of crops, combined with inadequate management practices, usually cause the deterioration of the physical and chemical quality of the soil. The aim of this study was to evaluate the changes in the physical and chemical attributes of a Typic Quartzipsamment from different land use systems and soil management. Four agroecosystems were selected: eucalyptus forest, extensive grazing, crop-livestock integration and integrated crop-livestock-forest, and an ecosystem preserved vegetation of native cerrado, located on Fazenda Modelo II in Ribas do Rio Pardo, MS. Soil samples were col-lected at depths of 0-5, 5-10 and 10-20 cm in a completely randomized design, with six plots of 150 m2 on each system. The integrated crop-livestock and integrated crop-livestock-forest provided the biggest contribution in the improvement of soil fertility. There was an antagonistic relationship between physical and chemical soil as sustainability evaluation, and chemical attributes had to be more affected than physical. © 2015, Universidade Federal Rural do Semi-Arid. All rights reserved. Source

This paper aims to discuss the scientific progress obtained in the past ten years in genetics and plant breeding, soil fertility and plant nutrition and the importance of target sward conditions for planning, controlling and recommending management grazing of tropical grasses. In addition, progress in crop-livestock integration systems and management alternatives for mitigation of greenhouse gas emission by beef cattle production systems, two very important areas related to sustainable production systems, will also be discussed. © 2010 Sociedade Brasileira de Zootecnia. Source

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