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Résultats 541-550 de 2,310
MODELAGEM DO PROCESSO DE SECAGEM DE SEMENTES DE FEIJÃO-CAUPI
2015
RAFAELA GREICI DA MOTTA CAMICIA | DIVAIR CHRIST | SILVIA RENATA MACHADO COELHO | RICARDO FERNANDO DA MOTTA CAMICIA
The study aimed to model the drying curves of cowpea beans (Vigna unguiculata (L.) Walp.) in different temperatures determine the coefficient of effective diffusion and the activation energy. For this, we used seeds of beans-cowpea cultivar BRS Guariba, harvested manually, with a water content of 21% (wet basis), dried until the water content 11% (wet basis). Drying was performed in the experimental dryer under controlled temperatures of 30, 40 and 50 °C ± 1 °C, and relative humidity of the air drying between 14 and 59%. 12 models of non-linear regression were tested and for selection the best model was considered to: the significance of the regression coefficient t test, the magnitude of the adjusted coefficient of determination (R²), the average relative error (P) and the estimated average error (SE). It was observed that the drying time for of the beans-cowpea seeds was 10,4 ; 5,6 ; and 2,1 h to the temperatures of 30, 40 and 50 °C, respectively; among the number tested, the mathematical model the Midilli was the best fit to experimental data. The coefficient of diffusion increases with temperature, with values between 5,047 x 10-11 to 12,011 x 10-11 m² s -1 for the temperature range from 30 to 50 °C. The relationship between the coefficient of diffusion effective and the drying temperature can be described by Arrhenius equation, which presents activation energy of 35,04 kJ mol-1 for spreading the liquid in the drying process of the of beans-cowpea seeds.
Afficher plus [+] Moins [-]NEMATÓIDE DAS LESÕES ASSOCIADO A MUDAS DE MANGUEIRA EM ASSU-RN
2015
GUSTAVO RUBENS DE CASTRO TORRES | RUI SALES JÚNIOR | LAUREEN MICHELLE HOULLOU | ANDREIA MITSA PAIVA NEGREIROS
The aim of this study was to report for the first time Pratylenchus brachyurus population asso- ciated to mango cv. Tommy Atkins seedling roots, on naturally infested soil, on Assú municipality, Rio Grande do Norte State. The population of nematode was characterized based on a morphometric study that was done using 20 females collected from the roots. The morphometric data were compared to other data published by different authors in studies concerning to reporters of this species of root - lesion nematode, and it was possible to identify the population as P. brachyurus.
Afficher plus [+] Moins [-]EFFECTS OF HARVEST MANAGEMENT AND MANURE LEVELS ON CACTUS PEAR PRODUCTIVITY
2015
JOÃO PAULO DE FARIAS RAMOS | EDSON MAURO SANTOS | GEORGE RODRIGO BELTRÃO CRUZ | RICARDO MARTINS ARAUJO PINHO | POLIANE MEIRE DIAS DE FREITAS
The aim of this paper was to evaluate the cutting frequency and levels of the manure on cactus for-age productivity. The research was conducted at Pendencia Station – The State Agribusiness Reaserch Compa-ny of Paraíba, Soledade – PB –Brazil, from August 2008 to August 2010. It was utilized a factorial arrenge-ment 4x5, 4 crop managements (M1= cactus forage harvested at 12 months after establishment; M2= cactus forage harvested at 12 months after the first regrowth; M3= harvested of the accumulated production in 24 months and M4= sum of the first production and regrowth) and five levels of goat manure: 0; 5; 10; 15 e 20 Mg ha-1. It was evaluated the fresh matter production (FMP) and dry matter production (DMP), water accumula-tion, rainfall use efficiency (RUE) and percentage of the water accumulation in the plant. The largest level of organic fertilizer promoted an increase in FMP of 275, 171, 184, 203% and DMP: 305, 175, 223, 218%, re-spectively, when comparing the highest level of fertilizer with the unfertilized treatment, and an increase in water accumulation 115.60, 102.93, 166.95, 218.53 kg of water ha-1 when comparing the highest level with the unfertilized treatment. The organic fertilization in M1, M2, M3 and M4 managements, despite of the levels, promoted a linear increase in the RUE. Fertilization increases the cactus forage productivity, and its rainfall use efficiency. The annual cut can be employed as a practice in the management of cactus forage.
Afficher plus [+] Moins [-]POLÍMERO HIDROABSORVENTE NA REDUÇÃO DE NUTRIENTES LIXIVIADOS DURANTE A PRODUÇÃO DE MUDAS DE MARACUJAZEIRO-AMARELO
2015
MIRIÃ CRISTINA PEREIRA FAGUNDES | MARIA DO CÉU MONTEIRO CRUZ | RAONI PEREIRA DE CARVALHO | JÉSSICA DE OLIVEIRA | BLENDA CALAZANS SOARES
The irrigation frequency to meet the water requirement for the production of passion fruit seed-lings can cause nutrients leaching, reducing the fertilization efficiency. Thus, the work was carried out to evalu-ate the effect of hydro-absorbent polymer in reducing losses of leached nutrients during the production of yel-low passion fruit seedlings. The factorial design 5 x 2 was used, distributed in a completely randomized design, being the factors represented by five doses of polymer (Hidroplan®-EB/HyB-M): 0, 0.5, 1.0, 1.5 and 2.0 g L-1 of substrate and two types of substrates: Bioplant® and Provaso® with four replications and 10 plants per plot. The polymer was incorporated into the substrates, making up the homogenization of the mixture at the time of planting. Irrigation was carried out daily sufficient to keep the substrate moisture control treatment at field ca-pacity, programmed by a system of automated irrigation sprinkler type. Collection of the leachate was carried out at 30 and 60 days after emergence of seed, which was submitted to laboratory analysis to determine the amount of nutrients leached. In the last evaluation determined the seedlings size and nutrient content in leaf dry mass. The incorporation of hydro-absorbent polymer to substrate reduced nutrient losses by leaching in the substrates. The losses reduction of leached nutrients favored the growth and increase of leaf nutrients in passion fruit seedlings with the polymer.
Afficher plus [+] Moins [-]CHEMICAL COMPOSITION, DIGESTIBILITY AND AEROBIC STABILITY OF CORN SILAGES HARVESTED AT DIFFERENT MATURITY STAGES
2015
CARLOS HENRIQUE SILVEIRA RABELO | ADAUTON VILELA DE REZENDE | FLÁVIO HENRIQUE SILVEIRA RABELO | FERNANDA CARVALHO BASSO | CARLA JOICE HÄRTER | RICARDO ANDRADE REIS
The objective of this study was to evaluate the effect of corn plant harvested in diferente ma-turity stages on the chemical composition, digestibility and aerobic stability of silages. The corn used in the study was the hybrid BM3061 harvested after 114, 121, 126, 133 and 140 days of sowing at five maturity stag-es based on the advancement of the grain milk line (early dent (ED), 1/3 of milk line (ML), 1/2 ML, 2/3 ML and black layer (BL)). A variation from 242.7 to 377.4 g of dry matter (DM) kg-1as fed was observed between the ED and BL stages; however, the measurements performed in this study did not exhibited major changes in the composition of these silages. The silages produced with plants that were harvested at the 1/2 ML, 2/3 ML and BL stages showed lower DM loss during the fermentative process. The silages produced with plants that were harvested at the ED and 1/3 ML stages showed higher in vitro organic matter digestibility (IVOMD) (0.584 and 0.631 g g-1 of OM, respectively). The corn silages produced at the maturity stage of 2/3 ML showed a higher aerobic stability (104 hours) during the aerobic exposure. The 1/3 and 2/3 ML maturity stages seem to be the best harvest stages for the production of corn silage in tropical climates.
Afficher plus [+] Moins [-]EFICIÊNCIA AGRONÔMICA DO CONSÓRCIO ALFACE-RÚCULA FERTILIZADO COM FLOR-DE-SEDA
2015
ANTONIO EWERTON DA SILVA ALMEIDA | FRANCISCO BEZERRA NETO | LUCAS RAMOS COSTA | MAIELE LEANDRO DA SILVA | JAILMA SUERDA SILVA DE LIMA | AURÉLIO PAES BARROS JÚNIOR
VARIABILIDADE DE ATRIBUTOS FÍSICOS DE UM LATOSSOLO VERMELHO SOB CULTIVO DE CANA-DE-AÇÚCAR
2015
DOUGLAS MARTINS PEREIRA PELLIN | RAFAEL MONTANARI | ELIZEU DE SOUZA LIMA | LENON HENRIQUE LOVERA | ADRIANY RODRIGUES CORRÊA
The goal of this paper was to select among the attributes surveyed soil, one with better repre-sentation to explain the variability of the technological components of sugar cane. The study was conducted at ETH Eldorado Plant in Rio Brilhante, MS, in the agricultural year 2011/2012, in a Oxisol, which was installed a geostatistical grid for data collection of soil and plant, with 80 sampling points, a 80 ha area. From the stand-point of linear and spatial TCH has been explained as a function of volumetric moisture. The volumetric mois-ture collected at a depth of 0.00 to 0.20 m, which had values between 0,24 to 0,270 m3 m-3, resulted in sites with the highest productivity of sugar cane per hectare from 64 to 70 t ha-1. To aid future studies aimed at preci-sion agriculture, which will use the same attributes as those of the future works, the values of ranges of spatial dependence to be used should be between 81 and 487 meters.
Afficher plus [+] Moins [-]EFEITO DE EXTRATOS DE Allamanda blanchetti NO CONTROLE DE Alternaria brassicicola EM MUDAS DE COUVE-MANTEIGA
2015
JULIANA DE SOUZA GRANJA BARROS | ERBS CINTRA DE SOUZA GOMES | LEONARDO SOUSA CAVALCANTI
The objective of this study was to evaluate the effect of the extract from a native plant from caatinga (Allamanda blanchetti) in the control of the fungus Alternaria brassicicola, concerning to induction of resistance mechanisms in seedlings of kale and direct fungitoxic action. Under greenhouse conditions, the seedlings of kale were sprayed with extracts from A. blanchetti extracted at hot and at cold at concentrations of 0; 100; 500 to 1000 ppm. Analysis of disease severity were performed at 5; 6; 7; 8; 9:10 days after inoculation. Peroxidases were analyzed five times 0; 24; 72; 120, and 168 hours after spraying the seedlings with the extracts. Furthermore, the capacity of the hot and cold extracts was also evaluated at 0; 100; 500, and 1000 ppm to inhibit the germination of spores of A. brassicicola. The concentrations of 1000 ppm of the hot and cold extracts were more effective in controlling the disease. The extract of A. blanchetti induced an increase in the peroxidase activity at 24 hours after treatment application and promote inhibition of germination of spores of A. brassicicola. These results indicate the potential from A. blanchetti to control A. brassicicola, both by direct action and the activation of defense mechanisms.
Afficher plus [+] Moins [-]SELEÇÃO INDIVIDUAL DE PLANTAS DE MARACUJAZEIRO AZEDO QUANTO À QUALIDADE DE FRUTOS VIA REML/BLUP
2015
MARCELO PEREIRA ASSUNÇÃO | WILLIAN KRAUSE | RIVANILDO DALLACORT | PAULO RICARDO JUNGES DOS SANTOS | LEONARDA GRILLO NEVES
Passion fruit is one of the major fruit crops grown in Brazil, however, the state of Mato Grosso culture has much to be explored. Thus, the aim of the study was to estimate the gain of plant selection of pas-sion fruit on the quality of fruit via REML/BLUP. The experiment was conducted in the State University of Mato Grosso, in its experimental area, in Tangará da Serra, Mato Grosso. It was evaluated eight crossing of commercial cultivars. It was used a randomized block experimental design with ten replications of ten plants per plot. From the genetic value found by the REML/BLUP methodology, it was applied the Mulamba Mock selection index in order to rank all individuals, selecting the 30 plants that showed the best performance for the evaluated characteristics. The high heritability values in the strict sense of the characteristics fruit weight (87%) and fruit length (65%) indicate possibilities for individual plant selection. The selection gain aiming fresh con-sumption was high for the characteristics fruit weight (13.38%), peel thickness (4.37%) and SST/ATT relation (3.61%). For industrial production selection requires special attention to the characteristics PP, SST and ATT, but the gains for PP (1.53%) and TSS (0.95%) did not stand out, however, the selection has raised other im-portant features as EC (-7.46%), CF (3.75%) and MF (1.77%).
Afficher plus [+] Moins [-]COMPOSIÇÃO QUÍMICA E ATIVIDADE ACARICIDA DO ÓLEO ESSENCIAL DE ERVA-DE-SANTA-MARIA SOBRE O ÁCARO-RAJADO
2015
LAUANA PELLANDA DE SOUZA | HUGO BOLSONI ZAGO | ADILSON VIDAL COSTA | PRISCILA STINGUEL | WILSON RODRIGUES VALBON
This study aimed to extract, identify the chemical composition and evaluate the acaricidal acti-vity of essential oil from Chenopodium ambrosioides L. (Amaranthaceae) on Tetranychus urticae Koch (Acari: Tetranychidae). Adult female spotted spider mite were treated with concentrations 5, 10, 15, 20 and 25 μL of essential oil per liter of air. Among the eight chemical substances that make up the essential oil of C. ambrosi-oides, the (Z)-ascaridol (81.40%) was the major component. The LC50 and CL90 found after 72 h of exposure to the essential oil were, respectively, 5.82 and 10.79 μL L-1 air and fecundity of females of T. urticae was redu-ced inversely proportional to the increased concentrations utilized in this study.
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