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LIXIVIAÇÃO DE POTÁSSIO EM UM CULTIVO DE PIMENTÃO SOB LÂMINAS DE IRRIGAÇÃO E DOSES DE POTÁSSIO
2011
FRANCIMAR DA SILVA ALBUQUERQUE | ÊNIO FARIAS DE FRANÇA E SILVA | AMANDA EMANUELLA ROCHA DE SOUZA | MÁRIO MONTEIRO ROLIM
With the aim of determining the concentration of potassium (K+) and electrical conductivity (EC) in water drainage in the cultivation of sweet pepper (Maximos F1), and to evaluate the possible risk of contamination of groundwater was conducted a experiment on a battery of 40 drainage lysimeters, whose experimental plot consisted of three plants in each lysimeter, located at campus of the Federal Rural University of Pernambuco (UFRPE), Recife, PE, in a completely randomized factorial scheme 5 x 2, with four replications, being five irrigation depth (80, 90, 100, 110 and 120% of ETc) and two levels of potassium (80 and 120 kg ha-1 of K2O), applied parceled according to phenological phase, through a drip irrigation system, with selfcompensable emitters. Throughout the cycle proceeded to the measurement of volumes generated from natural drainage and the fortnightly water balances in the lysimeters, and collection of samples for tests to determine the K+ and EC. The K+ content and the EC showed significant linear adjustments in all phases of the cycle, whose mean values were 9.79 mg L-1 and 0.35 dS m-1, respectively. The drained volume showed increases in certain events of water balance due to the high rainfall during the period, leaching more potassium ions. It was observed that with the application of higher blade and the higher dose losses were higher K2O, an average 60.10 kg ha-1.
Mostrar más [+] Menos [-]EFEITO DO CALCÁRIO DOLOMÍTICO E METASSILICATO DE CÁLCIO ASSOCIADO AO FÓSFORO EM LATOSSOLO VERMELHO-AMARELO CULTIVADO COM TOMATE
2011
FÁBIO MARTINS DE QUEIROGA | CELSEMY ELEUTÉRIO MAIA | ELIS REGINA COSTA DE MORAIS | MAURÍCIO DE OLIVEIRA
This work aimed to evaluate the effects of the fertilization with silica and its effect compared with limestone and interaction with the phosphorus in an Oxissol in tomato. A 5 x 2 factorial randomized block experimental design was adopted with four replication being five levels of metasilicate, five levels of limestone and two of phosphorus. In absence of phosphorus and in the presence limestone negative correlation was observed between stem diameter and content of Al in the soil and positive among stem diameter, root growth and content of P in the plant with the pH soil and the content of Ca in the soil. In the presence of phosphorus, positive correlation was verified among content of P in the plant and fresh matter of root with electrical conductivity of soil and root growth and content of Al in the soil. Using metasilicate of calcium in the absence of phosphorus, significant and positive correlation was observed for root growth with pH soil, Ca and sum of bases sum and content of P in the root with electrical conductivity of soil; in the presence of phosphorus, negative correlation was observed among Na and Al in soil. In the presence of phosphorus, was observed negative correlation among the stem diameter with pH, Ca, sum of bases and electrical conductivity of soil. For the leaf area, plant height, fresh matter in shoot and content of phosphorus in the root was verified significant and positive correlation with Na and the K in soil.
Mostrar más [+] Menos [-]ANÁLISE ESPAÇO-TEMPORAL DA QUALIDADE DA ÁGUA NA PARTE ALTA DA BACIA DO RIO SALGADO, CEARÁ
2011
SÁVIO DE BRITO FONTENELE | EUNICE MAIA DE ANDRADE | EVELINE VIANA SALGADO | ANA CÉLIA MAIA MEIRELES | RODOLFO JOSÉ SABIÁ
The aim of this research was to investigate the similarity of water quality in space and time in the upland of Salgado watershed, Ceará, Brazil. Multivariate analysis/Cluster Analysis was used for this investigation. Water samples were took in nine stations, spread out along the rivers during March, May, July, August and September, 2005, totalizing 45 samples. The water quality attributes analyzed were: electrical conductivity (EC), chloride (Cl-), sulphate (SO4-2), soluble orthophosphate (OPS), nitrate (NO3-), dissolved oxygen (DO), bicarbonate alkalinity (BA), total coliforms (TC) and turbidity (T). Four homogeneous groups were identified. The water samples collected at rainfall season defined the dissimilarity of group 1 in relation to the others. This group showed the best water quality due to the dilution of salts. Water samples collected during the end of rain-fall season and began of dry season formed group 2. Waters sampled at dry season in stations located down of discharge point of effluents defined group 3. These stations presented the highest concentrations of Cl-, EC, SO4-2 and TC. The values of NO3- and TC defined the similarity of group 4. Although Cl-, SO4-2, DO, and TC influenced the cluster definition, the most important variables were EC and NO3-. The water quality similarity was defined by two factors: punctual pollution and climatic seasonality.
Mostrar más [+] Menos [-]CRESCIMENTO E PRODUTIVIDADE DE SEMENTE DE MAMONA TRATADA COM LODO DE ESGOTO
2011
ALTINA LACERDA NASCIMENTO | REGYNALDO ARRUDA SAMPAIO | DELACYR DA SILVA BRANDÃO JÚNIOR | GERALDO RIBEIRO ZUBA JUNIO | LUIZ ARNALDO FERNANDES
Sewage sludge, waste from the stations of wastewater treatment, has high contents of organic matter and nutrients and, when stabilized, it presents enormous potential for agricultural use. This study aimed to evaluate the effect of doses of sewage sludge on growth and yield of castor bean. The experiment was conducted in Cambisol, using the cultivar Guarany AL 2002. The treatments in a randomized block design with four replicates, corresponding to a treatment with chemical fertilizer (90 kg ha-1 of P2O5 and 30 kg ha-1 K2O at planting and 40 kg.ha-1 N, 40 days after planting), and five doses of dry sewage sludge (0, 15, 30, 45 and 60 t ha-1). At the end of the cycle, the assessments were made of stem diameter, plant height and productivity. The productivity of seeds and the biometric characteristics of castor bean increased with increasing doses of sewage sludge applied to soil, and the dose from 15 t ha-1 is sufficient for replacement of mineral fertilization of culture without the risk of soil contamination with heavy metals.
Mostrar más [+] Menos [-]SUPERAÇÃO DA DORMÊNCIA E INFLUÊNCIA DO CONDICIONAMENTO OSMÓTICO EM SEMENTES DE Pterogyne nitens TUL. (FABACEAE)
2011
KELLY PELLIZZARO | VALQUÍRIA APARECIDA MENDES DE JESUS | ALESSANDRO DE LUCCA E BRACCINI | CARLOS ALBERTO SCAPIM | JOSELAINE VIGANÓ
The aim of this paper was to evaluate the influence of priming and efficiency of two methods of scarification on dormancy break of brave peanut seeds. After scarification with sulfuric acid and sandpaper, seeds were placed in mannitol solutions at concentrations 0.0 (control), -0.25, -0.50, -0.75 and -1.00 MPa for six days at 10 °C. Water content and germination percentage were determined. It was observed that, at 0.0 MPa, the seeds were scarified with H2SO4 had higher water content than the scarified with sandpaper, this may be related to uniform wear in the seed coat caused by H2SO4. For the water content, due the concentrations of mannitol, there was a significant linear response, only for the chemical scarification. However, it was observed null for both. The maximum responses of germination were 79.36% (chemical scarification) and 95.56% (scarification) with a maximum point of -0.41 MPa either. The scarification with sandpaper was most effective, however, at concentrations above -0.41 MPa, it was observed reduction in germination percentage.
Mostrar más [+] Menos [-]COMPOSIÇÃO NUTRICIONAL FOLIAR DA GÉRBERA IRRIGADA COM EFLUENTE DOMÉSTICO TRATADO
2011
LISÂNEA MYCHELINE OLIVEIRA DAMASCENO | ADERSON SOARES DE ANDRADE JÚNIOR | HANS RAJ GHEYI | NILDO DA SILVA DIAS | CLESCY OLIVEIRA DA SILVA
To evaluate the nutrient content of leaves of gerbera fertigated with treated domestic effluentswith and without mineral supplementation, a study was carried out in a greenhouse located at the Embrapa Meio-Norte in Teresina, Brazil from July to October 2007. The treatments studied were: T1 - 100% water and nutritional needs furnished with fertigation (N e K2 O); T2 - 25% volume of water through fertigation and 75% treated wastewater effluents (TWE); T3 - 50% volume of water through fertigation and 50% TWE; T4 - 75% volume of water with fertigation and 25% TWE; and T5 - volume of water 100% supplied through TWE. The leaf growth and plant development were favored by the application of 50% fertigation and 50% TWE (T3). At the end of experiment two adult leaves were collected in each treatment and content of nutrients was determined. Soil samples were also collected for analysis to verify alterations in physical and chemical properties.The soil irrigated with 100% wastewater effluent showed high concentrations of P, organic matter and low concentration of Na and K, but these changes did not cause any alteration in nutritional status of leaves and quality of gerberas flowers.
Mostrar más [+] Menos [-]CRESCIMENTO VEGETATIVO DE Opuntia ficus-indica EM DIFERENTES ESPAÇAMENTOS DE PLANTIO
2011
JOÃO PAULO DE FARIAS RAMOS | MAURICIO LUIZ DE MELLO VIEIRA LEITE | SALVINO DE OLIVEIRA JUNIOR | JOSÉ PEREIRA DO NASCIMENTO | EDSON MAURO SANTOS
The objective of this paper was to evaluate the vegetative growth, the chemical composition, the rain use efficiency and to determine the green and dry matter production of cactus forage cv. Italian (Opuntia ficus-indica Mill.), depending on planting spacing. The research was carried out at (EMEPA), in Soledade- Pb, from April 2007 to June 2008. The experimental design was in randomized blocks, with four repetitions. In order to evaluate crop under the four planting spacing (1 x 1; 1 x 0.5; 2 x 1; 2 x 0.5 m ) we measured plant height, number of cladodes per plant, and the order, length, width, perimeter, thickness and area of cladodes. There were no treatment effects (P > 0.05 ) on any of the growth variables evaluated, except for plant height and cladode width. The cactus pear showed low levels of fibrous carbohydrates, and planting spacing influenced levels of neutral detergent fiber. The phytomass production per area and rain use efficiency by cactus pear increased with increases in planting densities, with higher values observed for the spacing of 1 x 0.5 m; resulting in a greater quantity of forage produced per area and per unit of rain.
Mostrar más [+] Menos [-]ANÁLISE FITOQUÍMICA DE EXTRATOS BOTÂNICOS UTILIZADOS NO TRATAMENTO DE HELMINTOSES GASTRINTESTINAIS DE PEQUENOS RUMINANTES
2011
RENATA VALÉRIA REGIS DE SOUSA GOMES | VINÍCIUS LONGO RIBEIRO VILELA | ESCARIÃO DA NÓBREGA GOMES | ANA JOSICLEIDE MAIA | ANA CÉLIA RODRIGUES ATHAYDE
The preliminary investigation of chemical constituents of a plant allows the prior knowledge of the extract and indicates the nature of the present substances. The aim of this paper was to detect the absence or presence of appreciable amounts of various chemical constituents in extracts of jurubeba [Solanum paniculatum Linnaeus (1762)], capim santo [Cymbopogon citratus Stapf (1906)], batata de purga [Operculina hamiltonii (G. DON) D.F. Austin & Staples (1983)] and melão de são caetano [Momordica charantia Linnaeus (1763)], which has been indicated as alternative treatment against gastrintestinal helmintiasis of small ruminants. The jurubeba was collected in the city of Teixeira - PB. The capim santo, the batata de purga and the melão de são caetano were collected at the Centro de Saúde e Tecnologia Rural/UFCG, Patos - PB, in august and september of 2008. After, was realized the identification of the indicated shares to the ethnopharmacology study, deposited in the Herbário Caririense Dárdano de Andrade - Lima of the Universidade Regional do Cariri-URCA. The acquisition of the extract and phytochemical study followed the methodology described by Matos (1997). To obtain the extract was used the dust of the shares collected from each plant and as solvent ethanol PA. Four tests (phenols and tannins; anthocyanins, anthocyanidins and flavonoids; leucoanthocyanidins, catechins and flavanones; and alkaloids.) were conducted for the exploration of hydroalcoholical constituents. In the chemical assay were concluded that the ethanol extracts of the four plants with compounds such as tannins and catechins, and absence of phenols, anthocyanins and proanthocyanidins.
Mostrar más [+] Menos [-]ZONEAMENTO AGROCLIMÁTICO DA PITANGUEIRA PARA TRÊS CENÁRIOS DISTINTOS DE PRECIPITAÇÃO PLUVIAL EM PERNAMBUCO
2011
ALEXSANDRO OLIVEIRA DA SILVA | ANA PAULA NUNES DA SILVA | GEBER BARBOSA DE ALBUQUERQUE MOURA | PABRICIO MARCOS OLIVEIRA LOPES | SERGIO RICARDO RODRIGUES DE MEDEIROS
The present work had as objective to carry through the agroclimatic zoning of the culture of surinam cherry in the state of Pernambuco. They had been used given average annual of minimum and maximum pluvial precipitation and pertaining temperatures of air the 201 climatologic station located in the main representative cities of the regions of the State for the elaboration of the water balance and the attainment of the thermal and water limits. The function density of probability of the distribution gamma was used to classify the dry, regular and rainy years. The maps of dry, regular and rainy years had been produced using interpolation for kriging. The results had presented 19 cities with full aptitude for dry years, 50 cities for regular years and 66 cities for rainy years apt to the culture of surinam cherry. The cities of Cortês, Gameleira and Palmares had revealed with better aptitudes agroclimatic for the culture of the surinam cherry in Pernambuco.
Mostrar más [+] Menos [-]DETERMINAÇÃO DOS PERÍODOS CRÍTICOS DE OCORRÊNCIA DE INCÊNDIOS FLORESTAIS NA ESTAÇÃO ECOLÓGICA DO SERIDÓ, SERRA NEGRA DO NORTE-RN
2011
JOSÉ AUGUSTO DA SILVA SANTANA | ITÂNIA MARIA MEDEIROS DE ARAÚJO | CLAUDIUS MONTE DE SENA | ALEXANDRE SANTOS PIMENTA | FRANCISCO DAS CHAGAS ESTEVAM DA FONSECA
The Caatinga is one of the richest Brazilian biomes, however its biodiversity is constantly threatened by human activities, especially the use of fire for cleaning and/or increase areas for agricultural activities. In this study, it's determined the months and the days with highest risk of forest fires in the Seridó Ecological Station in Serra Negra do Norte-RN and was developed with daily data of precipitation and relative humidity of the years 1999-2004, collected in the Climatological Station, through Monte Alegre Formula. The results show that in January, February, March, April and May, the rainy season in the region, are the months with the lowest fire danger, are classified as null to very high risk, while August, September, October, November and December, dry season in the region, reached the highest degree of danger, being classified as high to very high risk. During the study period almost 75% of days had high to very high fire hazard while the levels null and small together reached more than 13%, more occurring in the months January to April.
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