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SEED MORPHOMETRY AND GERMINATION OF Aechmea costantinii (Mez) L. B. Sm. (BROMELIACEAE)
2016
PETRÚCIO ALEXANDRE FONSECA RIOS | JOAO CORREIA ARAÚJO NETO | VILMA MARQUES FERREIRA | MARIA INAJAL RODRIGUES DA SILVA DAS NEVES
The potential economic and environmental benefits brought by bromeliads production are significant. It is noteworthy that the high degree of degradation of some ecosystems as the Atlantic forest involve reduction of these species. This factor has been worsened by the elevated degree of endemism of these plants, e.g. Aechmea costantinii (Mez) L. B. Sm., which is a high ornamental potential bromeliad but understudied. Thus, the present research aimed to characterize physical and morphological features of A. costantinii fruit and seeds, describing the different stages of post - seminal development, as well as evaluating seed germination behavior with respect to temperature and light. For this purpose, we used fruit and seeds freshly harvested from an Atlantic Forest fragment, located in the city of Maceió, Alagoas State, Brazil. Tests were carried out under a completely randomized design, in a 6x4 factorial scheme (temperature x light) with four replications of 25 seeds. The polyspermic fruit are of tricarpellate/triloculate type and originated from inferior ovary, containing an average of 73 elliptical and mucilaginous seeds with basal embryo. The germination is epigeal - type and occurs in a great intensity and high speed at 35 °C, regardless light presence or quality.
Mostrar más [+] Menos [-]GROWTH OF Mimosa caesalpiniifolia Benth., UNDER SHADE IN THE NORTHEAST SEMI-ARID REGION OF BRAZIL
2016
JOSÉ RIVANILDO DE SOUZA PINTO | JEFERSON LUIZ DALLABONA DOMBROSKI | JOSÉ HERMOGENES DOS SANTOS JUNIOR | GABRIELA OLIVEIRA DE SOUZA | ROMULO MAGNO OLIVEIRA DE FREITAS
Seedling production for reforestation aims to achieve the best plant growth in a minimal amount of time, to provide good survival and growth levels after transplantation. During cultivation, it is necessary to know the shading levels that lead to the best growth. The objective of this study was to assess the growth of young Mimosa caesalpiniifolia Benth. plants provided with various amounts of shade in the northeast semi-arid region of Brazil. Four types of shade cloth were tested (0, 30, 50 and 70%). Shoot length, stem diameter, stem dry matter, leaf dry matter, total dry matter and leaf area were assessed. Leaf area ratio, specific leaf area, absolute growth rate, relative growth rate and net assimilation rate were also calculated. The different shading levels affected M. caesalpinifolia growth, with the best growth indicators observed in plants grown under 50% shade, with increases in plant height, leaf area and total dry matter observed compared to the full sun condition.
Mostrar más [+] Menos [-]CHAMOMILE PRODUCTION USING SUPPLEMENTARY IRRIGATION AND ORGANIC FERTILIZATION IN SANDY SOILS
2016
CATARINY CABRAL ALEMAN | PATRICIA ANGÉLICA ALVES MARQUES | ANA CLAUDIA PACHECO
The use of medicinal plants in the herbal medicine of Brazilian Health System has intensified production and the need for developing efficient agricultural techniques that promote greater productivity of these species. The objective of this work was to evaluate the chamomile production at field conditions as a function of irrigation depths and organic fertilizer rates. The experiment was conducted in the Universidade do Oeste Paulista (Campus II experimental area), in Presidente Prudente, São Paulo State, Brazil. A triple factorial experimental design was used, consisting of irrigation rates (150, 100, 75, 50, 25 and 0% of the reference evapotranspiration - ETo), organic manure types (poultry and cattle manure) and manure rates (0, 3 and 5 kg m-2), with four replications. The capitula production per plant, capitula dry weight and yield per water input (water use efficiency) were evaluated. The supplementary irrigation combined with organic manure fertilization provided the highest capitula yield for chamomile crop in the Presidente Prudente region. The combination of poultry manure at rate of 5 kg m-2 with water depth equal to 150% of the ETo resulted in higher average values of capitula fresh and dry weight and water use efficiency.
Mostrar más [+] Menos [-]IMPACT OF SALINE CONDITIONS AND NITROGEN FERTILIZATION ON CITRUS PRODUCTION AND GAS EXCHANGES
2016
JÔNATAS RAULINO MARQUES DE SOUSA | HANS RAJ GHEYI | MARCOS ERIC BARBOSA BRITO | DIEGO AZEVEDO XAVIER | GUILHERME DE FREITAS FURTADO
In two simultaneous experiments, we evaluated the impact of brackish irrigation water and nitrogen (N) fertilization on the production of citrus (scion-rootstock combinations) and its associated gas exchanges. These experiments were conducted at the Campus of Federal University of Campina Grande, Brazil in a protected environment (shade screens on the sides) using drainage lysimeters. Experiment I used a randomized block design (3 replicates), in a 5 × 3 factorial arrangement, corresponding to five water salinity levels (0.6, 1.2, 1.8, 2.4, and 3.0 dS m-1) and three scion-rootstock combinations: RS1– Common Sunki mandarin (TSKC) × Poncirus trifoliata English (TRENG) - 256; RS2– Common Rangpur lime (LCRSTC); and RS3– TSKC × (Rangpur lime (LCR) × P. trifoliata (TR)) - 059; with Mimo do Céu orange as the scion variety. Experiment II used a randomized block design (3 replicates), in a 3 × 2 factorial arrangement, corresponding to the three scion/rootstock combinations and two nitrogen (N) doses (100 and 200 mg kg-1 of soil). Plants were irrigated with water of 3.0 dS m-1. For both experiments, gas exchanges and mean mass of fruits were evaluated at harvest. Gas exchanges were inhibited in plants under saline stress. Plants grafted with Common Rangpur lime showed greater production potential than did the other genotypes studied, even under brackish water conditions.
Mostrar más [+] Menos [-]CHARACTERIZATION OF YELLOW LATOSOLS (OXISOLS) OF SERRA DO QUILOMBO, IN PIAUÍ STATE SAVANNA WOODLANDS - BRAZIL
2016
ROSSANNA BARBOSA PRAGANA | VALDOMIRO SEVERINO DE SOUZA JUNIOR | REGIANA DOS SANTOS MOURA | JORDÂNIA MEDEIROS SOARES
The savanna woodlands of Piauí state has great economic importance since it is an area for agricultural expansion, being the fourth most important of Brazil and the first from Brazilian Northeastern. The area accounts for 5.9% of the Brazilian savanna woodlands and 36.9% of the Northeastern savanna, covering 46% of the Piauí state area, in a total of 11.5 million hectares . The goal of this research was to study pedoenvironments of Serra do Quilombo region, which is in Piauí state savanna, as well as identifying existing soil classes, according to the Brazilian System of Soil Classification - SiBCS. Soil identification consisted in characterizing soil profiles along a transect, assessing in - field conditions and collecting soil samples, in areas of native vegetation. The samples were gathered from three distinct points, being two at the edges and one at the center of the plateau. Soil analyses were carried out with samples collected from each horizon through trench digging up to a 2 - m depth. Morphological, physical, chemical and mineralogical characterizations were performed for each soil profile , along with an evaluation of the effect of pedogenic factors on their formation and development. All soils under study were formed with source materials of the same geological formation; however, each rock has a distinct contribution to the process, involving sandstones and shales. The characteristics observed in the soil from Serra do Quilombo have no difference from the pattern found in the Brazilian plateaus, and soil profiles were classified as dystrophic clayey Yellow Latosols (Oxisols), according to the SiBCS .
Mostrar más [+] Menos [-]PHYSICOCHEMICAL CHARACTERISTICS OF PURPLE LETTUCE HARVESTED AT DIFFERENT AGES
2016
LORENA DE OLIVEIRA MOURA | LANAMAR DE ALMEIDA CARLOS | KÊNIA GRASIELLE DE OLIVEIRA | LUMA MOREIRA MARTINS | ERNANI CLARETE DA SILVA
Lettuce is one of the most produced and consumed leafy vegetables in Brazil. It is harvested when the plant reaches full vegetative growth and the leaves are still tender and there are no signs of bolting. The plant is unsuitable for commercialization after this period, thus, a food that is rich in vitamins, minerals and bioactive compounds such as carotenoid is lost. Therefore, the objective of this work was to assess the purple lettuce quality based on physical-chemical characteristics, in three different ages. The experiment was conducted in an urban community garden in Sete Lagoas MG, Brazil. A completely randomized experimental design was used with three replications. The treatments consisted of three development stages (20, 30 and 40 days after transplanting - DAT). The treatment with 40 DAT presented total carotenoids concentration and soluble solids content significantly higher, lower pH, and darker lettuce, with lower values of the parameter b* (increase in yellow color), and higher values of the parameter a* (increase in red color), compared to the first two treatments. The titratable acidity was statistically equal for the three evaluation periods. Considering the high concentration of carotenoids found at 40 DAT, the harvest can take place at this age.
Mostrar más [+] Menos [-]INFLUENCE OF IRRIGATION LEVELS AND PLANT DENSITY ON "SECOND-SEASON” MAIZE
2016
LUIS HUMBERTO BAHÚ BEN | MARCIA XAVIER PEITER | ADROALDO DIAS ROBAINA | ANA RITA COSTENARO PARIZI | GIDEON UJACOV DA SILVA
This study assessed the effect of different irrigation levels and plant densities on maize crops cultivated during the second season in the Western Border region of the State of Rio Grande do Sul. This work was conducted at the Federal Institute of Farroupilha – Alegrete Campus/RS – between January and June 2014. Treatments were arranged in a completely randomized 5 × 4 factorial design, with 3 replicates each. Irrigation of fixed amounts of water that were based on the evapotranspiration of the culture (Etc): 0, 50, 75, 100, and 125% of Etc were applied at 5-day intervals. Four densities of plants were defined (4, 7, 10, and 13 plants m-2). We assessed number of maize ears per plant, number of grains per ear, aboveground dry matter, mass of 100 grains, harvest index, and grain productivity. The number of grains per ear, mass of 100 grains, and grain yield were influenced by irrigation levels. Plant density and water depth influenced the number of grains per ear, the mass of 100 grains, and grain productivity. The highest yield of winter maize grain was achieved with a combination of 13 plants per m-2 and an irrigation level of 100% of Etc. Specific densities of plants maximized the yield of maize at each irrigation level, demonstrating that choice of plant density is a critical variable in the second crop of maize, and significantly influences the components of production.
Mostrar más [+] Menos [-]SOIL MANAGEMENT SYSTEMS FOR SUSTAINABLE MELON CROPPING IN THE SUBMEDIAN OF THE SÃO FRANCISCO VALLEY
2016
VANDERLISE GIONGO | ALESSANDRA MONTEIRO SALVIANO | MÔNICA DA SILVA SANTANA | NIVALDO DUARTE COSTA | JONY EISHI YURI
Changes in soils management systems, including the application of green manure, are able to increase crop productivity. The aim of this study was to propose a soil management system with the use of green manure to improve the nutritional status and melon productivity in the submedian of the São Francisco Valley. The experiment was installed in Typic Plinthustalf and conducted in split plot. There were two soil tillage systems, tillage (T) and no tillage (NT), and three types of green manure (two vegetal cocktails: VC1- 75% legumes (L) + 25% non-legumes (NL); VC2- 25% L+ 75% NL and spontaneous vegetation (SV)). The experimental design was a randomised block with four replications. Fourteen species of legumes, grasses and oilseeds were used for the composition of the plant cocktails. We evaluated production of the dry shoot and root biomass and carbon and nutrient accumulation by green manures and melon plant. Data were subjected to analysis of variance and the treatment means were compared by Tukey´s test (P<0.05). Shoot biomass production and carbon and nutrient accumulation were higher in plant mixtures compared to spontaneous vegetation. The root system of the plant cocktails added larger quantities of biomass and nutrients to the soil to a depth of 0.60 m when compared to the spontaneous vegetation. The cultivation of plant cocktails with soil tillage, regardless of their composition, is a viable alternative for adding biomass and nutrients to the soil in melon crops in semi-arid conditions, providing productivity increases.
Mostrar más [+] Menos [-]FLORISTIC-STRUCTURAL CHARACTERIZATION AND SUCCESSIONAL GROUP OF TREE SPECIES IN THE CERRADO BIOME OF TOCANTINS STATE, BRAZIL
2016
EDER PEREIRA MIGUEL | ALBA VALÉRIA REZENDE | FABRÍCIO ASSIS LEAL | REGINALDO SÉRGIO PEREIRA | RAFAEL RODOLFO DE MELO
The objective of this study was to characterize the floristic composition, vegetation structure and ecological group of tree species in a cerradão forest (Cerrado biome) of Palmas, Tocantins State, Brazil. A forest inventory was performed in an area of 10.15 hectares, using systematic sampling with plots of 400 m², in which all standing trees, alive and dead, that had diameter at breast height (DBH) ≥ 5 cm were sampled and identified. A linear plateau regression model (LPR) was used for sample sufficiency analysis. The Shannon index (H’) was used for assess the floristic diversity, and the Importance Value Index (IVI) for assess the horizontal structure. The forest was classified in three strata according to vertical structure analysis. The LPR showed that the sampling size was adequate. The predominate species in the area were Myrcia splendens, Emmotum nitens and Qualea parviflora, and species from the families Fabaceae and Chrysobalanaceae. The pioneer (613 individuals ha-1) and climax (530 individuals ha-1) species were the predominating groups. Regarding the richness index, the number of climax (57 species) and pioneer (25 species) species stood out. The alpha floristic diversity was 3.35 nats individuals-1 and the Pielou equability value J = 0.76. The diametric distribution showed a negative and balanced exponential pattern. Regarding the vertical stratification, the smallest amount of individuals was in the upper stratum (13%) and the highest in the mid stratum (63%) and in the lower stratum (24%). The use of floristic composition tools with horizontal and vertical structure analysis was effective for understand the tree community, which may be considered structured and diverse, thus able to restructure possible disturbances when preserved.
Mostrar más [+] Menos [-]GENOTYPE-ENVIRONMENT INTERACTIONS ON THE WEIGHT OF TABAPUA CATTLE IN THE NORTHEAST OF BRAZIL
2016
LAAINA DE ANDRADE SOUZA | CARLOS HENRIQUE MENDES MALHADO | JOSÉ BRACCINI NETO | RAIMUNDO MARTINS FILHO | PAULO LUIZ SOUZA CARNEIRO
The objective of this work was to verify the presence of genotype - environment interactions (GEI) on the weight adjusted to 365 days of age (W365) for Tabapua cattle in the Northeast of Brazil, using reaction norm (RN) models. The reaction norm model with homogeneous residual variance and 1 - step provided the best fit to the data by the criteria information of deviance, deviance based on the conditional predictive ordinate and deviance based on the Bayes factors. Direct and maternal heritability estimates for the animal model were 0.17±0.04 and 0.07±0.03, respectively. The direct heritability for model reaction norm in the low and high management environment were 0.21±0.06 and 0,70±0.04, respectively. The correlations between the slope and intercept of the reaction norm were 0.68±0.10 and 0.96±0.06 for the direct and maternal effect, indicating that the animals with high genetic values respond positively to environment improvements, especially for the maternal effect. The Spearman correlations between the sire classifications ranged from 0.14 to 0.94 in the different environments and models. Genetic values of most animals were robust to environmental variation, however, considering the sires with the highest number of progeny, there is the presence of GEI.
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