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ATIVIDADE ACARICIDA DE EXTRATOS AQUOSOS DE PLANTAS DE CAATINGA SOBRE O ÁCARO VERDE DA MANDIOCA Full text
2014
FELIPE FERNANDO DA SILVA SIQUEIRA | JOSÉ VARGAS DE OLIVEIRA | CÉLIA SIQUEIRA FERRAZ | CARLOS ROMERO FERREIRA DE OLIVEIRA | CLÁUDIA HELENA CYSNEIROS MATOS
The undesirable effects of agrotoxics have aroused the interest of society to use alternative tactics of pest control, as plants with insecticidal activity, which can be used as powders, aqueous and organic extracts, essential oils and emulsifiable. This way, the toxicity, population growth and repellence of aqueous extracts of plants were evaluated on the cassava green mite, Mononychellus tanajoa . Aqueous extracts of Cro- ton blanchetianus , Myracrodruon urundeuva and Ziziphus joazeiro were used, in which were immersed in cas- sava leaf discs (3.5 cm diameter). The extracts at all concentrations (1, 5, 10, 15, 20 and 25%) resulted in a de- cline in the pest population. The concentrations of 20 and 25% of the extracts resulted in the highest percentage mortality of the pest. All extracts in concentrations of 15, 20 and 25% for adult females were repellents M. ta- najoa .
Show more [+] Less [-]MODELING OF WATER INFILTRATION IN SOIL CULTIVATED WITH EUCALYPTUS AND PASTURE Full text
2014
ANDRÉ QUINTÃO DE ALMEIDA | ARISTIDES RIBEIRO | YASMIN PAIVA RODY | WELLIAM CHAVES MONTEIRO DA SILVA | FERNANDO PALHA LEITE
The rio Doce river basin has great silvicultural potential, areas cultivated with pasture are con- verted to forest plantations. Physical processes in the soil, especially the infiltration water, are very dependent on the type and management of its coverage. The objective of the present study was to evaluate the differences between rates of water infiltration in soils submitted to eucalyptus plantations and pasture and adjust empirical models of infiltration. The experiment was conducted at four sites in the Rio Doce river basin, MG, Brazil, where two were planted with eucalyptus and two with pasture. Five infiltration tests using the concentric rings method were performed in each area. Results show that the soils infiltration rate with eucalyptus plantations were higher than those found in soils from pasture areas, with stable infiltration rates of 78 and 165 mm h-1 in eucalyptus and 47 and 50 mm h-1 in pasture. The model of Horton indicated the highest adjusted confidence index for the four sites analyzed.
Show more [+] Less [-]CRITÉRIOS PARA A SELEÇÃO DE LINHAGENS DE SORGO EFICIENTES E RESPONSIVAS AO FÓSFORO Full text
2014
FABRICIO RODRIGUES | JURANDIR VIEIRA DE MAGALHÃES | CÉSAR AUGUSTO BRASIL PEREIRA PINTO | FLÁVIO DESSAUNE TARDIN | ROBERT EUGENE SCHAFFERT
The optimization of nutritional efficiency is critical to increase productivity and reduce produc- tion costs. However, the identification of lines with greater efficiency and responsiveness to phosphorus is of great importance, with the in intention to join the hybrid, these traits at once and, moreover, the best way to select them. Thus, the objective of this study was to evaluate which characters should be considered in the se- lection of genotypes efficient and responsive to phosphorus in sorghum. The correlations were split into direct and indirect basic variables of efficiency and responsiveness to phosphorus through path analysis. The character that most influenced the efficiency of sorghum lines to phosphorus was harvest index to utilization efficien- cy and dry matter to absorption efficiency and use, under conditions of stress. Under conditions of adequate phosphorus fertilization, the trait with the greatest influence for evaluation of responsiveness was dry grain mass to the apparent recovery efficiency, physiological and agronomic.
Show more [+] Less [-]MEDICINAL PLANTS FROM BRAZILIAN CAATINGA: ANTIBIOFILM AND ANTIBACTERIAL ACTIVITIES AGAINST Pseudomonas aeruginosa Full text
2014
DANIELLE SILVA TRENTIN | KARINE RIGON ZIMMER | MÁRCIA VANUSA SILVA | RAQUEL BRANDT GIORDANI | ALEXANDRE JOSÉ MACEDO
The Caatinga biome covers a vast area in northeastern Brazil and presents a high level of biodiversity. It is known that about 400 plant species are used by semi-arid local communities for medical purposes. Based on ethnopharmacological reports, this study aims to screen 24 species from Caatinga regarding the ability to prevent biofilm formation and to inhibit the growth of Pseudomonas aeruginosa - a major opportunistic human pathogen and an important causative agent of morbidity and mortality. The effects of aqueous extracts, at 0.4 and 4.0 mg mL-1, on biofilm formation and on growth of P. aeruginosa ATCC 27853 were studied using the crystal violet assay and the OD600 absorbance, respectively. The most active extracts were analyzed by thinlayer chromatography and high performance liquid chromatography. Our investigation pointed extracts of four species with potential application for the control of P. aeruginosa: Anadenanthera colubrina (Vell.) Brenan, Commiphora leptophloeos (Mart.) J.B. Gillett, Myracrodruoun urundeuva Allemão, whose antibiofilm effects (89%, 56% and 79% inhibition of biofilm, respectively) were associated with complete inhibition of bacterial growth, and Pityrocarpa moniliformis (Benth.) Luckow & R.W. Jobson, which were able avoid 68% of biofilm formation and inhibited 30% bacterial growth. The qualitative phytochemical analyses reveal the complexity of the samples as well as the presence of compounds with high molecular weight.
Show more [+] Less [-]PRODUÇÃO DE FITOMASSA E DECOMPOSIÇÃO DE RESÍDUOS CULTURAIS DE PLANTAS DE COBERTURAS NO CULTIVO DA SOJA EM SUCESSÃO Full text
2014
JOSÉ LUIZ RODRIGUES TORRES | MAYCON GABRIEL DE SOUZA SILVA | MATHEUS DE ANDRADE CUNHA | DANIELA XENOFONTE PEREIRA VALLE | MARCOS GERVASIO PEREIRA
The plant species used as ground cover preceding the commercial crops cultivation in the Cerrado must be adapted to the climate and soil of the region, so they have high biomass productivity and offset the decomposition high rates that occurs in these regions. This study aimed to evaluate the biomass yield and the decomposition rate of residues of different cover crops preceding soybean cultivation in Uberaba-MG, Brazil. The experiment was conducted in 2011/12 period in a randomized complete block design in plots with 2 m2 with treatments comprise the following covers: jack bean, millet, sunn hemp and brachiaria. It was evaluated: the dry biomass yield, the decomposition rate through of the bags decomposition, productivity, number of beans per plant, and mass of 100 soybean grains. The millet was the plant cover that showed the highest yield of dry biomass (5.22 Mg ha-1) during the study period. The decomposition of crop residues occurred at accelerated rate until to complete 120 days and after that the rate slowly up until 240 days. Sunn hemp and jack bean were the cover crops with the decomposition highest rates and the smaller half-lives were observed; soybean yield was not affected by the soil covers.
Show more [+] Less [-]QUALIDADE DE RAÍZES DE MANDIOCA DE MESA MINIMAMENTE PROCESSADA NOS FORMATOS MINITOLETE E RUBIENE Full text
2014
CLARISSA SOARES FREIRE | ADRIANO DO NASCIMENTO SIMÕES | MARCOS RIBEIRO DA SILVA VIEIRA | AURÉLIO PAES BARROS JÚNIOR | FRANCISCLEUDO BEZERRA DA COSTA
This study aimed to quantify the agro - industrial income and evaluating the quality of cassava minimally processed in minitolete and rubiene shapes. The assays were performed at the Academic Unit of Serra Talhada/ Federal Rural University of Pernambuco. Roots of sweet cassava cv. Mossoró were harvested at 14 months of age, minimally processed in minitolete and rubiene shapes and stored at 5 ± 2 °C and 90 ± 5 % of relative humidity for 11 days. Agroindustrial income, accumulated fresh weight, pH, soluble solids, soluble sugars and cooking time were evaluated. The experimental design was completely randomized in 2x6 factorial design, referring to shapes (minitolete and rubiene) and refrigerated storage times (0, 3, 5, 7, 9 and 11 days), respectively, with 3 replications. The agroindustrial income for each shape was calculated only at the end of minimal processing. The cooking time was measured at 0 and 11 days in 2x2 factorial design. The formats 'minitolete' and 'rubiene' minimally processed sweet cassava showed agroindustrial income above 60%. There- fore, it is suggested the minimum processing of sweet cassava in those shapes. Furthermore, the quality of the shapes was kept preserved throughout the 11 days of refrigerated storage. The 'rubiene' favored higher mean values of soluble sugars giving this format greater sweetness.
Show more [+] Less [-]ELABORAÇÃO DE BEBIDA TIPO NÉCTAR DE GRAVIOLA ADOÇADA COM MEL DE Apis mellifera Full text
2014
DYEGO DA COSTA SANTOS | ANGELITA DA SILVEIRA MOREIRA | EMANUEL NETO ALVES DE OLIVEIRA | YVANA MARIA GOMES DOS SANTOS
The objective of this st udy was to prepare drinks type soursop nectars sweetened with honey from Apis mellifera , by use of experimental planning, varying the concentrations of pulp and soluble solids content and evaluate the effect of these in the physical and chemical characteristics of processed drinks. Were used a factorial planning 2 2 with three experiments in central point resulting in seven experiments. The soursop pulp was diluted with potable water to obtain products in the concentrations of 25, 30 and 35% (w/w) of pulp. The correction of soluble solids to 11, 12 and 13 °Brix was made using honey from A. mellifera . It was ob- served that all formulations of drinks type soursop nectar sweetened with honey were in accordance with bra- zilian legislation. The mathematical equations fitted to the data of titratable acidity, total sugar, ratio, brightness and intensity of yellow were significant, and only the models fitted to the values of titratable acidity, total sug- ars and ratio were predictive. The responses of titratable acidity, total sugar, ratio, brightness and yellow color intensity were influenced by factors pulp concentration and total soluble solids content, wherein the concentra- tion of soursop pulp had greater influence on the acidity and the ratio and the content final total soluble solids of the beverages, modified by the addition of honey, showed greater influence on the content of total sugars and lightness values. The yellow intensity response showed influences of both factors.
Show more [+] Less [-]CULTIVO DE FEIJÃO-CAUPI EM LATOSSOLOS SOB O EFEITO RESIDUAL DA ADUBAÇÃO FOSFATADA Full text
2014
MARLENE ALEXANDRINA FERREIRA BEZERRA | FRANCISCO ASSIS DE OLIVEIRA | FRANCISCO THIAGO COELHO BEZERRA | WALTER ESFRAIN PEREIRA | SHERLY APARECIDA DA SILVA
The cowpea considered one of the main dietary sources of tropical and subtropical regions. To population of the regions North and Northeast of Brazil represents an important socioeconomic activity. The objective of this study was to evaluate growth characteristics of cowpea under the residual effect of phosphorus fertilization. Research conducted on the screened greenhouse of the Department of Soil Science and Agricul- tural Engineering, Center of Agricultural Sciences, Federal University of Paraiba, Areia-PB. The substrates used were materials Oxisol textures of sandy clay and sandy clay franc that we fertilized with levels of 0, 40, 80, 120, and 160 kg ha-1 of P2O5. After fertilization, the cultures we performed with sunflower, corn and beans, respectively. Were analyzed the stem diameter, main branch length, leaf area, shoot dry weight and water con- sumption. The effect of residual phosphorus was significant for leaf area, dry weight of shoots and water con- sumption. The effect of soil was significant for all variables evaluated, except for the consumption of water. Phosphorus fertilization in sunflower, followed by maize cultivation has a positive effect on growth and water use by cowpea, third culture. The Oxisol of sandy clay loam texture led to the highest in diameter at ground level, main branch length and leaf area of cowpea.
Show more [+] Less [-]MORFOFISIOLOGIA E PRODUÇÃO DE FEIJÃO - CAUPI, CULTIVAR BRS NOVAERA, EM FUNÇÃO DA DENSIDADE DE PLANTAS Full text
2014
ANTÔNIO AÉCIO DE CARVALHO BEZERRA | ADÃO CABRAL DAS NEVES | FRANCISCO DE ALCÂNTARA NETO | JOSÉ VALDENOR DA SILVA JÚNIOR
The objective of this study was to evaluate morphophysiologic and productive characteristics from a modern variety of cowpea, cv BRS Novaera, under different plant densities. The experiment was con- ducted out at city of Alvorada do Gurguéia - PI, under irrigation system in the agricultural year 2009/2010. We evaluated five plant populations (100; 200; 300; 400 and 500 thousand plants per hectare) in a randomized complete block design with four replications, using BRS Novaera. The increase in population from 100 thou- sand to 500 thousand plants ha - 1 led to reductions of 78.18% in the number of branches, 66.53% in the number of pods per plant,59.53% in grain yield and, on average,of65.76% and 72.65% for biomass and plantlet af area, respectively. The pod length and weight of on hundred seeds was not significantly influenced by different plant populations. The different plant densities promoted significant changes in morphological and physiological characteristis, yield component sand grain yield.
Show more [+] Less [-]CAPACIDADE PREDATÓRIA DE Ceraeochrysa cubana SOBRE Aleurocanthus woglumi Full text
2014
ROBÉRIO DE OLIVEIRA | PAULO ROBERTO RODRIGUES ALVES | WYARA JÉSSICA DIAS COSTA | JACINTO DE LUNA BATISTA | CARLOS HENRIQUE DE BRITO
The present study verified the consumption capacity of Ceraeochrysa cubana when fed nymphs of Aleurocanthus woglumi. The experiments were conducted at the Laboratory of Entomology, Departamento de Fitotecnia e Ciências Ambientais, Universidade Federal da Paraíba – Areia/PB. Was used a completely randomized design in a factorial arrangement. The research was conducted in climatic chamber, regulated to 26 ± 2ºC, 70 ± 10% relative humidity and 12 hours photophase. The predation of C. cubana was evaluated for the three larval instars (1st, 2nd and 3rd), and as prey, nymphs of 1st, 2nd, 3rd or 4th instars of A. woglumi, with 10 repetitions per treatment. The larvae were individualized in Petri dishes (9.0 x 1.5 cm), with as standard food (control) Sitotroga cerealella eggs. The consumption among the predator instar among nymphs was higher and increasing for the first instar nymphs of A. woglumi. The total predation among the predator instar was higher when fed with nymphs of first instar of A. woglumi. The predator when fed with second instar nymphs of A. woglumi had higher intake in the 3rd larval stage. The green lacewing C. cubana is promising as a control agent of A. woglumi in biological control program, considering the infestations with nymphs of first instar of A. woglumi.
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