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Effgen T.A.M.,Institute Defesa Agropecuaria e Florestal do Espirito Santo IDAF | Passos R.R.,Federal University of Espirito Santo | Andrade F.V.,Federal University of Espirito Santo | Lima J.S.D.S.,Federal University of Espirito Santo | And 2 more authors.
Revista Ceres

Agricultural soils are subject to change in their properties, according to the type of use and management systems adopted. The objective of this study was to evaluate, in different sampling sites, the physical properties of soils cultivated with conilon coffee under different managements in the South of Espirito Santo State, Brazil. Samples were collected from the layers 0,00-0,20 m and 0,20-0,40 m in the upper part of the coffee plant canopy, in relation to the direction of the slope. Coffee crops, representative of the South of the Espirito Santo State, with the same soil class (dystrophic Red Yellow Latosol (Oxisol) hilly relief), were used for the study, including the following managements: M1 - drip irrigation, liming every two years, fertilization, cleared and use of the straw of conilon; M2 - manuring, cleared and weedings; M3 - weedings and mowing. For each management, the following sampling sites were evaluated: UT -upper third, MT - medium third; LT - lower third, along the slope. The physical soil properties evaluated were: bulk density, total porosity, macroporosity, microporosity and soil resistance penetration. For the experimental conditions, the soil resistance penetration, the macroporosity and microporosity important physical indicators of the quality of the soil were shown, influenced by the management, sampling site and evaluation depth. Source

Braun H.,Federal University of Vicosa | Fontes P.C.R.,Federal University of Vicosa | Finger F.L.,Federal University of Vicosa | Busato C.,Institute Defesa Agropecuaria e Florestal do Espirito Santo IDAF | Cecon P.R.,Federal University of Vicosa
Ciencia e Agrotecnologia

This study aimed to evaluate the effect of nitrogen (N) doses on carbohydrate (total soluble sugars, reducing sugars and starch), dry matter and total soluble solids contents in tuber of four potato cultivars. The tubers originated from four experiments, simultaneously conducted in the field, during fall/winter, at the Federal University of Viçosa. These experiments were set in randomized complete block and four repetitions and we evaluated the effects of five N rates (0, 50, 100, 200, and 300 kg ha-1) on Agata, Asterix, Atlantic and Monalisa cultivars. Dry matter, total soluble sugars, reducing sugars, starch, and total soluble solids contents of the tubers were analyzed after a 30-day storage at 5°C. N rates presented quadratic effects on the total soluble solids and presented no effects on dry matter and starch contents for all cultivars. Depending on the cultivar, N rates had positive effects or did not affect reducing sugars and total soluble sugars contents in the tubers. Source

Busato C.,Institute Defesa Agropecuaria e Florestal do Espirito Santo IDAF | Fontes P.C.R.,Federal University of Vicosa | Braun H.,Federal University of Vicosa | Busato C.C.M.,Instituto Federal do Espirito Santo IFES
Revista Ciencia Agronomica

The objective of this research was to establish the appropriated mathematical model to estimate leaf area of potato cultivar Atlantic using the linear dimensions of the leaf: the length (C) and width (L). The evaluation was performed in 270 leaves, which were randomly collected from a field of Universidade Federal de Viçosa, 21 and 50 days after the plant emergence (DAE). In laboratory, the length, width and area of each leaf were measured by a leaf area meter (model LI 3100). The data were submitted to a regression analysis with the AF value as a dependent variable and the leaf length, width, the product of both (CL), and the square product (CL) 2 values as independent variables. Potato plant LA was more precisely estimated using measures of length and width: AF = 0,369335**CL + 10,6923 (R 2 = 0,92) to 21 DAE and AF = 0,470971**CL - 16,3432 (R 2 = 0,86) to 50 DAE. With the obtained model, AF of potato cultivar Atlantic can be estimated by measures obtained straight from the field, with no the need to damage the leaf or the plant. Source

Chagas E.,Institute Defesa Agropecuaria e Florestal do Espirito Santo IDAF | Araujo A.P.,Federal Rural University of Rio de Janeiro | Alves B.J.R.,Embrapa Agrobiologia | Teixeira M.G.,Embrapa Agrobiologia
Revista Brasileira de Ciencia do Solo

Seeds with a high concentration of P or Mo can improve the growth and N accumulation of the common bean (Phaseolus vulgaris L.), but the effect of enriched seeds on biological N2 fixation has not been established yet. This study aimed to evaluate the effect of seeds enriched with P and Mo on growth and biological N2 fixation of the common bean by the 15N isotope dilution technique. An experiment was carried out in pots in a 2 × 3 × 2 × 2 factorial design in randomized blocks with four replications, comprising two levels of soil applied P (0 and 80 mg kg-1), three N sources (without N, inoculated with rhizobia, and mineral N), two seed P concentrations (low and high), and two seed Mo concentrations (low and high). Non-nodulating bean and sorghum were used as non-fixing crops. The substrate was 5.0 kg of a Red Latosol (Oxisol) previously enriched with 15N and mixed with 5.0 kg of sand. Plants were harvested 41 days after emergence. Seeds with high P concentration increased the growth and N in shoots, particularly in inoculated plants at lower applied P levels. Inoculated plants raised from high P seeds showed improved nodulation at both soil P levels. Higher soil P levels increased the percentage of N derived from the atmosphere (%Ndfa) in bean leaves. Inoculation with the selected strains increased the %Ndfa. High seed P increased the %Ndfa in inoculated plants at lower soil P levels. High seed Mo increased the %Ndfa at lower soil P levels in plants that did not receive inoculation or mineral N. It is concluded that high seed P concentration increases the growth, N accumulation and the contribution of the biological N2 fixation in the common bean, particularly in inoculated plants grown at lower soil P availability. Source

Serrano L.A.L.,EMBRAPA - Empresa Brasileira de Pesquisa Agropecuaria | Marinato F.A.,Institute Defesa Agropecuaria e Florestal do Espirito Santo IDAF | Magiero M.,Federal University of Espirito Santo | Sturm G.M.,Federal University of Espirito Santo
Revista Ceres

The diseases caused by soil pathogens have brought severe losses to black pepper because of plant premature death. Thus, the objective of this work was to evaluate the production of black pepper (Piper nigrum) clonal cuttings in commercial substrate fertilized with five doses of controlled-release fertilizer. It was evaluated three genotypes 'Guajarina', 'Iaçará' and 'Cingapura', cultivated in plastic bags filled up with commercial substrate composed by pinus bark and vermiculite (without soil) fertilized with five doses of controlled-release fertilizer of the formula NPK 15-09-12: 0.0, 2.5, 5.0, 7.5 and 10 kg m-3. At 120 days after transplanting, the results showed growth differences among genotypes for all parameters, except plant height. The controlled-release fertilizer doses interfered on plants growth, but the interaction genotype x doses was observed only for leaf number, root dry matter and total dry matter. The highest values for total dry matter were recorded for cv. Guajarina, while cv. Cingapura showed the lowest value. The highest values for total dry matter of black pepper cuttings were obtained with the doses 4.4 kg m-3 for 'Guajarina'; 6.4 kg m-3 for 'Iaçará' and 5.3 kg m-3 for 'Cingapura'. Source

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