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NEMATÓIDE DAS LESÕES ASSOCIADO A MUDAS DE MANGUEIRA EM ASSU-RN
2015
TORRES, GUSTAVO RUBENS DE CASTRO | SALES JÚNIOR, RUI | HOULLOU, LAUREEN MICHELLE | NEGREIROS, ANDREIA MITSA PAIVA
ABSTRACT: The aim of this study was to report for the first time Pratylenchus brachyurus population associated 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. | RESUMO: O objetivo do presente trabalho foi relatar, pela primeira vez, população de Pratylenchus brachyurus associada a raízes de mangueira cv. Tommy Atkins no estádio de muda em solo naturalmente infestado no município de Assú, Rio Grande do Norte. A caracterização da referida população do nematóide foi fundamentada em estudo morfométrico realizado em 20 fêmeas coletadas das raízes. Os dados morfométricos foram comparados aos dados publicados por diferentes autores em trabalhos sobre a ocorrência da referida espécie de nematóide das lesões e permitiram a identificação da população como pertencente à P. brachyurus.
Afficher plus [+] Moins [-]REQUERIMENTO HÍDRICO E COEFICIENTE DE CULTURA DO MILHO E FEIJÃO-CAUPI EM SISTEMAS EXCLUSIVO E CONSORCIADO
2015
SOUZA, LUCIANA SANDRA BASTOS DE | MOURA, MAGNA SOELMA BESERRA DE | SEDIYAMA, GILBERTO CHOHAKU | SILVA, THIERES GEORGE FREIRE DA
RESUMO: Objetivou-se determinar a necessidade de água e o coeficiente de cultura para as diferentes fases fenológicas do milho ( Zea mays L) e do feijão-caupi ( Vigna unguiculata (L) Walp) em sistemas de plantio exclusivo e consorciado sob as condições climáticas do Semiárido brasileiro. O experimento foi conduzido no município de Petrolina, PE. Foram monitorados o rendimento de matéria seca total da parte aérea e a radiação fotossinteticamente ativa interceptada para ambas as culturas. Além disso, obteve-se a evapotranspiração da cultura (ETc) por meio do método do balanço de água no solo. Com estes dados e a evapotranspiração de referência foi obtido o coeficiente de cultura (Kc), os quais foram utilizados, posteriormente, para ajustar modelos em função dos graus dias acumulados. Com os resultados, constatou-se que o requerimento hídrico do milho e feijão-caupi no sistema de plantio consorciado foi maior que no sistema exclusivo. Os valores de Kc no consórcio foram de 0,90, 1,30, 1,20 e 0,72 para o milho, e 0,86; 1,30, 1,21 e 0,91 para o feijão-caupi, respectivamente, para as fases vegetativa, floração, enchimento de grãos e maturação. No sistema exclusivo esses valores foram de, 0,86, 1,23, 0,97 e 0,52 para o milho e de 0,68; 1,02, 1,06 e 0,63 para o feijão-caupi, nesta ordem. As variações dos valores de Kc para ambos os sistemas e culturas estiveram associadas ao incremento de biomassa e a interceptação da radiação. O modelo Gaussiano ajustado descreveu adequadamente a relação entre os valores de Kc e dos graus dias acumulados. | ABSTRACT: In order to determine the water requirement and crop coefficient for the different phenological stages on corn plants ( Zea mays L.) and cowpea plants ( Vigna unguiculata (L.) Walp) in intercropping and sole cropping systems under the climatic conditions of the Brazilian semiarid. The experiment was conducted in the city of Petrolina, PE. Shoots total dry mass and photosynthetically active radiation intercepted for both crops were monitored. Furthermore, it was obtained the evapotranspiration (ETc) by the soil water balance method. With these data and reference evapotranspiration it was obtained crop coefficient (Kc), which were subsequently used to adjust models as a function of accumulated degree days. With the results, it was found the water requirements from maize and cowpea intercropped system were greater than the sole system. Kc in the intercropped system was 0.90, 1.30, 1.20 and 0.72 for maize and 0.86, 1.30, 1.21 and 0.91 for cowpea, respectively, for the vegetative, flowering, grain filling and ripening stages. In the sole system, these values were, 0.86, 1.23, 0.97 and 0.52 for maize and 0.68, 1.02, 1.06 and 0.63 for cowpea in those phases mentioned. The variations of the Kc values for both systems and cultures have been associated to the increase of biomass and light interception. The Gaussian model adjusted properly described the relationship between Kc and accumulated degree days.
Afficher plus [+] Moins [-]PROBABILIDADE DE OCORRÊNCIA DOS ATRIBUTOS QUÍMICOS EM UM LATOSSOLO SOB PLANTIO DIRETO
2015
DIAS, MÁRCIO JOSÉ | ALVES, SUELI MARTINS FREITAS | REIS, ELTON FIALHO DOS | OLIVEIRA, DANILO GOMES DE
RESUMO: Este trabalho teve como objetivo avaliar a variabilidade espacial utilizando o método de krigagem indicativa na elaboração de mapas de probabilidade da ocorrência de atributos químicos do solo e produtividade. Os dados foram coletados em uma área de solo cultivados com soja no sistema de plantio direto com uma malha regular de amostragem de 60 x 60 m, totalizando 124 pontos. Em cada um destes foram coletadas amostras deformadas do solo para a determinação dos atributos químicos (pH, Potássio, Cálcio, Magnésio e Alumínio trocáveis, Fósforo disponível, Zinco, acidez potencial, matéria orgânica do solo, capacidade de troca catiônica e saturação por bases). Para a determinação da produtividade foram coletadas todas as plantas dentro de 1 m² do ponto amostral. Os dados foram categorizados em códigos binários em função dos valores apresentados na recomendação para o uso de corretivos e fertilizantes. Posteriormente, foi utilizada a análise geoestatística. Os atributos potássio, fósforo, magnésio e saturação por bases apresentaram dependência espacial e foram submetidos à krigagem, como a técnica de interpolação. Foram elaborados mapas de probabilidade de ocorrência dos atributos avaliados que apresentaram dependência espacial. Os mapas probabilísticos mostraram que a região central da área avaliada apresentou maior probabilidade de necessidade de correção para os teores dos atributos potássio, fósforo, magnésio e saturação por bases. A partir da análise dos mapas foi possível detectar áreas com deficiência de nutrientes e realizar correções e utilização de técnicas de manejo de forma localizada, minimizando o custo operacional e econômico dessa cultura. | ABSTRACT: This study aimed to evaluate the spatial variability using the indicative kriging method in preparing probability maps of the occurrence of soil chemical properties and productivity. Data were collected in a ground area planted with soybeans in a no-till system, with a regular grid sampling of 60 x 60 m, totaling 124 points. At each point were deformed soil samples collected to determine the chemical attributes (pH, Potassium, Calcium, Magnesium and Aluminum exchangeable, available phosphorus, zinc, potential acidity, soil organic matter, cation exchange capacity and base saturation). To determine productivity were collected all the plants within 1 m² of the sample point. Data were categorized into binary codes on the amounts presented in the recommendation for the use of lime and fertilizer. Later it used the geostatistical analysis and attributes potassium, phosphorus, magnesium and base saturation that presented spatial dependence underwent kriging as interpolation technique. Occurrence probability maps were drawn of the evaluated attributes presented spatial dependence. The probabilistic maps showed that the central area evaluated was more likely to need correction to the levels of potassium attributes, phosphorus, magnesium and base saturation. From the analysis of the maps, you can detect nutrient deficient areas and making corrections and use of localized management techniques, minimizing operating costs and economic that culture.
Afficher plus [+] Moins [-]PHYSIOLOGICAL QUALITY OF SOYBEAN SEEDS UNDER MECHANICAL INJURIES CAUSED BY COMBINES
2015
PACHECO, FÁBIO PALCZEWSKI | NÓBREGA, LÚCIA HELENA PEREIRA | LIMA, GISLAINE PICOLLO DE | SANTORUM, MÁRCIA | BOLLER, WALTER | FORMIGHIERI, LORIVAN
RESUMO: A colheita mecânica acarreta danificações nas sementes e pode comprometer sua qualidade. Neste contexto, objetivou-se neste trabalho, diagnosticar e avaliar o efeito de duas colhedoras: uma com sistema de trilha de fluxo axial e outra com sistema de trilha de fluxo tangencial, sob três regulagens de abertura do côncavo (1; 30 e 1 mm, para colhedora de fluxo axial e 3,0; 15 e 3,0 mm, para colhedora de fluxo tangencial) e três rotações do cilindro (1100; 450 e 650 ou 930, dependendo do grau de umidade das sementes de 13,7% e 16,6%, respectivamente, para colhedora de fluxo axial e 1000; 500 e 550 ou 800 rpm, dependente do grau de umidade de 13,7% e 16,6%, respectivamente, para colhedora de fluxo tangencial) sobre a qualidade das sementes da cultivar de soja "ND 4910". Teores de água diferenciados foram obtidos em diferentes horários de colheita. A qualidade da semente foi avaliada pelos testes de germinação, índice de velocidade de germinação, velocidade de germinação, grau de umidade, porcentagem de pureza e vigor pelo teste de tetrazólio. Independente da colhedora, os resultados obtidos permitiram concluir que o dano mecânico foi o que mais reduziu a qualidade das sementes, com 16,6% de grau de umidade, abertura de côncavo de 3 mm (axial) e 1 mm (tangencial) e rotação do cilindro de 1100 rpm (axial) e 1000 (tangencial), ambas com as maiores rotações de cilindro utilizadas. | ABSTRACT: The mechanical harvesting causes injuries on seeds and may affect their quality. Different threshing mechanisms and their adjustments may also affect the intensity of impacts that machines cause on seeds. So, this study aimed at diagnosing and evaluating the effect of two combines: the first one with a threshing system of axial flow and the other one with a threshing system of tangential flow, under adjustments of concave opening (10 mm, 30 mm and 10 mm for a combine with axial flow and 3.0 mm, 15 mm and 3.0 mm for a combine with tangential flow) and three cylinder rotations on the quality of soybean seeds harvested at two moisture contents. Soybean seeds of cultivar 'ND 4910' were harvested at 16.6% moisture (mid-morning) and 13.7% moisture in the afternoon. The seeds quality was evaluated by germination tests, germination speed index (GSI), germination rate, moisture content, percentage of purity and vigor by tetrazolium test. Despite the combine, the results showed that the mechanical injury has most reduced seeds quality, at 16.6% moisture content, concave opening of 30 mm (axial) and 10 mm (tangential) and cylinder rotation of 1100 rpm (axial) and 1000 (tangential), both with the highest rotations used. The combine with tangential flow had the highest degree of seeds purity. When seeds moisture content at harvest was close to 13.7%, there was the highest seed injury, while, at 16.6%, there was the highest number of crushed soybeans, regardless the combine adjustment.
Afficher plus [+] Moins [-]ATRIBUTOS QUÍMICOS DO SOLO E ESTADO NUTRICIONAL DE COQUEIROANÃO FERTIGADO COM NITROGÊNIO E POTÁSSIO
2014
MIGUEL FERREIRA NETO | JOSÉ SIMPLÍCIO DE HOLANDA | HANS RAJ GHEYI | MARCUS VINÍCIUS FOLEGATTI | NILDO DA SILVA DIAS
The objective of this work was to study the effects of N and K2O doses applied through fertigation in soil fertility and nutritional status. The experiment was carried out during April, 2002 until March 2004, on Experimental Farm of the Empresa de Pesquisa Agropecuária of the State of Rio Grande do Norte (EMPARN), Brazil. The statistical design was in a completely randomized block with 4 replication, using for composition of treatments Plan Puebla III experimental matrix, treatments being composed of combination of two factors: nitrogen and potassium doses in the form of urea and potassium chloride, respectively. In all 10 treatments, defining the interval for N (256 to 4874 g plant-1 year-1) and K2O (258 to 4872 g plant-1 year-1) were applied through fertigation with microsprinkler irrigation system. The contents of nutrients in the soil presented great variation and tended to decrease with time. The doses of N decreased the pH and contents of Ca and Mg although increased the availability of P in soil and favored its absorption by plant. A negative gradient in concentration of nutrients under fertigation was observed from the soil surface. The K content in leaf 14 were increased with increase in doses of K2O via fertigation presenting high correlation with number of fruits. The application of K in soil increased the contents of Cl and Mg in leaf 14 and decreased the contents of Na, while the application of N in soil increased the contents of Mn in leaves.
Afficher plus [+] Moins [-]CULTIVO DE FEIJÃO E MILHO EM SUCESSÃO A PLANTAS DE COBERTURA
2014
JOSÉ LUIZ RODRIGUES TORRES | MATHEUS DE ANDRADE CUNHA | MARCOS GERVASIO PEREIRA | DINAMAR MARCIA DA SILVA VIEIRA
Growing cover crops preceding planting common beans and corn may influence the yield of these cash crops. This study aimed to evaluate the biomass production and decomposition of crop residue cover and yield of maize and beans grown on these soils as coverings of plants. The experiment was conducted under field conditions in the 2011/12 harvest in Uberaba. With a randomized block designed in a split - plot scheme, seven cover crops were used : sunn hemp ( Crotalaria spectabilis ), jack bean ( Canavalia ensiformis DC.), mil- let ADR300, ADR500 and ENA2 ( Pennisetum glaucum L.), Sorgo (S orghum bicolor L.) and brachiária ( Urochloa brizantha cv Marandú), and subplots in annual succession crops (maize and bean). The millets ADR300, ADR500 and ENA2 among Poaceae and jack beans between Fabaceae produced more dry biomass (9.8, 8.9, 8.6 and 3.8 t ha - 1 ), respectively; after 150 days of decomposition of plant residues of sunn hemp, jack bean, sorghum, brachiaria, millet ADR500, millet ENA2 and millet ADR300 were in the order of 67.9; 71.7; 53.8; 61.7; 49.9; 45.5 and 46.7%, respectively; the maize yield was higher when the culture was grown on resi- dues of millet ENA2 (7.2 t ha - 1 ) and jack bean (6.8 t ha - 1 ), while the bean was higher when grown on millet ADR300 (1.3 t ha - 1 ) and sunn hemp (1.2 t ha - 1 ).
Afficher plus [+] Moins [-]PERDAS PÓS-COLHEITA EM UVA DE MESA REGISTRADAS EM CASAS DE EMBALAGEM E EM MERCADO DISTRIBUIDOR
2014
THALITA PASSOS RIBEIRO | MARIA AUXILIADORA COÊLHO DE LIMA | SANDRA OLIVEIRA DE SOUZA | JOSÉ LINCON PINHEIRO ARAÚJO
The postharvest losses index for fruits in Brazil is high. To attend the quality exigencies and minimize those losses, it is initially necessary to detect the problems on the commercialization chain. Because of that, this study aimed to evaluate the postharvest losses in table grapes during the operations carried out in packinghouses of firms located in Petrolina-Pernambuco State/Juazeiro-Bahia State region and during the com- mercialization in Mercado do Produtor de Juazeiro. The study was carried out in three packinghouses and in three sell places of the Mercado do Produtor de Juazeiro. In the packinghouses, it was observed one day of ac- tivity, following the normal procedures. For sampling, the wasted fruits were weighted, characterized according the kind of loss and quantified before doing another weighting for each identified category. In Mercado do Pro- dutor de Juazeiro, the study was carried out in a similar way, including the same evaluations. Because of the rigorous quality criteria, the percentage of losses in table grapes in packinghouses was 3.9%. This percentage was higher than the value observed in Mercado do Produtor de Juazeiro, which was 1.5%. The main cause of postharvest losses in grapes was mechanical injury in both studied conditions.
Afficher plus [+] Moins [-]MODELING OF WATER INFILTRATION IN SOIL CULTIVATED WITH EUCALYPTUS AND PASTURE
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.
Afficher plus [+] Moins [-]QUALIDADE DE FLORES DE GIRASSOL ORNAMENTAL IRRIGADA COM ÁGUA RESIDUÁRIA E DOSES DE ESTERCO
2014
LEANDRO OLIVEIRA DE ANDRADE | HANS RAJ GHEYI | NILDO DA SILVA DIAS | REGINALDO GOMES NOBRE | FREDERICO ANTONIO LOUREIRO SOARES | ELKA COSTA SANTOS NASCIMENTO
The management of wastewater in agricultural crops in order to explore fully their potential of water and nutrients, have proved a viable alternative for irrigated agriculture, especially in semiarid regions. The objective of this work was to study the quality of ornamental sunflower (cv. Sol Noturno) with increasing doses of cattle manure and types of water. The experiment was conducted in a completely randomized block design in factorial scheme (4 x 2), with four replications and five plants per replication, testing two types of water (supply water and treated wastewater) and four doses of cattle manure (5, 10, 15 and 20% in on weight basis) In determining the quality of sunflowers morphological and growth variables were analysed. The manure doses ranging from 15 to 16.7% provided the best morphological and growth characteristics of sunflowers. The nanure dose less than 8.4% provided early onset and opening of buds of the sunflower and the highest number of flower buds was obtained with the manure dose equivalent to 14%. The types of water, as well as the interaction between the factors did not significantly influence the quality of sunflowers (cv. Sol Noturno).
Afficher plus [+] Moins [-]RENDIMENTO DA BATATA-DOCE ADUBADA COM NITROGÊNIO E ESTERCO BOVINO
2014
FRANCISCO DE ASSIS PEREIRA LEONARDO | ADEMAR PEREIRA DE OLIVEIRA | WALTER ESFRAIN PEREIRA | OVIDIO PAULO RODRIGUES DA SILVA | JULIANE RAFAELE ALVES BARROS
This study was carried out during April to August of year 2009, in field conditions at the horti- culture department Centro de Ciências Agrárias – Universidade Federal da Paraíba, in Areia – PB, aiming to evaluate the effect of nitrogen rates in the presence and absence of bovine manure in the sweet potato yield. The experimental design used was randomized blocks, with four repetitions in factorial scheme 6 x 2, being six nitrogen doses ( 0, 50, 100, 150, 200, 250 kg ha-1 of nitrogen) in the presence and absence of bovine manure. The evaluated variables were commercial roots average weight, commercial roots production plant-1 and com- mercial productivity of roots. The average weight of commercial roots, depending on nitrogen doses in the presence of bovine manure has increased in a linear way in order 0,31 g each kg of nitrogen applied, with maxi- mum weight 233,6 g with 250 kg of nitrogen ha-1. In bovine manure absence it was achieved average weight of 192,1 g. The maximum productivity of commercial roots plant-1 in the presence of bovine manure was 235,42 g, obtained with 243,75 kg ha-1 of nitrogen. In organic fertilizer absence, it was achieved the average of 127,1 g of commercial roots plant-1, depending on nitrogen doses. The dose of 183 kg ha-1 of nitrogen was responsible by maximum productivity of 13,6 t ha-1 of commercial roots, in the presence of bovine manure, while in its absence was achieved medium productivity of 7,9 t ha-1. The cattle manure increased the efficiency of nitrogen production characteristics of sweet potato and set nitrogen use in coverage and cattle manure at planting pro- vides marketable yield of sweet potato than the national average.
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