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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

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    Spatial distribution of the root system of Conilon and Arabica coffee plants
    (Empresa Brasileira de Pesquisa Agropecuária - Embrapa, 2020) Partelli, Fabio Luiz; Cavalcanti, André Cayô; Menegardo, Camilo; Covre, André Monzoli; Gontijo, Ivoney; Braun, Heder
    The objective of this work was to evaluate the root system of Conilon coffee (Coffea canephora) and Arabica coffee (Coffea arabica) plants in the soil profile, using semivariograms. The evaluations were carried out in an area located in the municipality of Jaguaré, in the state of Espírito Santo, Brazil. The Verdebrás G30/G35 Conilon coffee and the Catuaí Vermelho IAC 44 Arabica coffee cultivars were assessed. Soil monoliths with coffee plant roots were collected at three distances from the trunk in the planting row and at six distances from the trunk between rows, at six depths. The roots were collected and washed and then digitized and processed in the Safira software. The spatial variability of the evaluated attributes was characterized by the geostatistical technique, through semivariograms, using the GS+ 7.0 software. Root surface area, length, and volume were quantified for the two coffee species. Conilon coffee plants have a tendency of showing a root system with a smaller surface area, shorter length, and lower volume by volume of soil, as well as a less discrepant distribution on soil surface and in deeper layers, compared with Arabica coffee.
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    Ionic speciation in a dystrophic red latosol under coffee crop high doses of gypsum
    (Editora UFLA, 2019-07-03) Ramos, Bárbara Zini; Lima, José Maria de; Serafim, Milson Evaldo; Coscione, Aline Renée; Ferraz, Raul Magalhães; Amorim, Lucas Mota; Lopes, Guilherme
    The cultivation of coffe crops in Brazil, especially on Latosols, has been increasing over the years, despite limitations such as aluminum toxicity, low fertility and very long drought periods. In this scenario, soil amendments to mitigate these restraints are necessary. Since these limitations are not restricted to the arable layer, application of gypsum becomes an efficient alternative to sustain soil fertility and deepen the root system to get water from the deeper layers of soil. However, high doses of gypsum can cause unbalance among Ca 2+ , Mg 2+ and K + . The objective of this work was to evaluate these bases as well as their ionic pairs, and the presence of sulfate along the soil profile 16 months after the application of high gypsum doses in a Latosol under coffee crops. An inicial dose of gypsum was applied in the entire area, followed by four treatments, in triplicate and randomized blocks, set as follows: G0 - zero gypsum applied over the planting line after the initial soil preparation; G7- 7 t ha -1 of gypsum in the planting line (1.75 kg m -1 ); G56 - 56 t ha -1 of gypsum in the planting line (14 kg m -1 ), all with brachiaria between the coffee planting lines; and CV7 - 7 t ha -1 of gypsum in the line and no brachiaria between the planting lines. The soil profile was sampled in layers up to 2.40 m depth and the soil solution was extracted by suctioning the sample-saturated paste. Following this extraction, the soil solution was analyzed by combustion for total carbon contents, ion chromatography and ICP-OES/flame photometry, for chemical species, and speciation was done using Minteq software. After 16 months of gypsum application, 96% of K + in soil solution was at 0.35 to 0.45 m in its free form. Leaching of Ca 2+ and Mg 2+ occurred predominantly in their free forms, although a more significant contribution of CaSO 40 and MgSO 40 ionic pairs was observed when compared to K 2 SO 40.