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Physiological maturation of seeds of Eugenia pyriformis Cambess and Eugenia involucrata DC
Priscilla Oro,Deisinara Giane Schulz,Karoline Branco Bandeira,Cátia Raquel Volkweis
Biotemas , 2012,
Abstract: The genus Eugenia presents several fruit species with a potential for cultivation. This study aimed to analyze the physiological maturation of seeds of Eugenia pyriformis Cambess and Eugenia involucrata DC. Fruits were manually collected from eight adult trees in the town of Santa Helena, Parana, Brazil. They were characterized into four stages according to pigmentation for E. pyriformis and into five stages for E. involucrata. The evaluations consisted of germination test, mean germination time calculation, and determination of seeds dry weight and moisture content. The design adopted was completely randomized, with four replications of 25 seeds. Data underwent a variance analysis and the average values were compared through Tukey test at 5% probability. The pigmentation of E. pyriformis and E. involucrata fruits may be used as a parameter for the evaluation of physiological maturity of seeds. One suggests collecting seeds of E. pyriformis between the green/yellow and yellow/orange fruit pigmentation stages, and in the bright red fruit pigmentation stage regarding E. involucrata.doi: 10.5007/2175-7925.2012v25n3p11
Tolerancia à desseca??o de sementes de espécies de Eugenia
Delgado, Liliana Ferreira;Barbedo, Claudio José;
Pesquisa Agropecuária Brasileira , 2007, DOI: 10.1590/S0100-204X2007000200016
Abstract: the objective of this work was to evaluate the desiccation tolerance of seeds of six fruit species of eugenia (e. brasiliensis lam., e. cerasiflora miq., e. involucrata dc., e. pyriformis camb., e. umbelliflora berg. and e. uniflora l.) aiming to provide information for the conservation of the germinability of these seeds during storage. seeds were dried continuously in oven (40oc) or closed chambers with silica gel (25oc) until 10% water content. after drying, samples of the seeds were analyzed for water content and germination. as water content decreased, seeds lost viability, independently of the drying method. seeds from each species differed on sensitivity to desiccation, but all seeds were intolerant to levels lower than 45% water content and lost viability at levels lower than 15%.
Germina??o in vitro e armazenamento do pólen de Eugenia involucrata DC (Myrtaceae)
Franzon, Rodrigo Cezar;Raseira, Maria do Carmo Bassols;
Revista Brasileira de Fruticultura , 2006, DOI: 10.1590/S0100-29452006000100008
Abstract: the objective of the present work was to determine a suitable medium and conditions for in vitro germination of rio-grande-cherry (eugenia involucrata dc) pollen. possibility of storage in freezer (-16,5°c) was also studied. the pollen was collected from flowers at balloon stage and right after anthesis. the tested media were: the standard (10% sucrose, plus 1% agar dissolved in distilled water), and the addition of two h3bo3 (0.65mm and 1.3mm) to this medium. temperatures of incubation of 25 and 30oc were tested. independent of the treatment the incubation period was three hours. incubation at 25°c in the standard medium provided good germination (61.4%). boron did not influence the pollen germination. pollen collected from flowers right after anthesis showed high germination percentage. the rio-grande-cherry pollen conserved the viability (60.0%) after 90 days of storage at -16,5°c. however, after 220 and 280 days it was reduced to 40.6% and 24.2% and, after 530 days, there was total loss of viability.
Desinfesta??o superficial de explantes isolados de ramos semilenhosos e herbáceos de Eugenia involucrata DC. (Myrtaceae)
Golle, Diego Pascoal;Reiniger, Lia Rejane Silveira;Bellé, Rogério Ant?nio;Curti, Aline Ritter;
CERNE , 2013, DOI: 10.1590/S0104-77602013000100010
Abstract: this study aimed to compare two methods of surface disinfestation of explants isolated from semi-hardwood and herbaceous branches of eugenia involucrata dc. (myrtaceae) to obtain aseptic cultures. the better control of bacterial contamination in nodal segments from semi-hardwood branches was obtained by immersion for 25 minutes in sodium hypochloride at 1.5%. however, 39.35% of explants showed bacterial colonies and excessive contamination made it impossible the cultures. apical and nodal shoot segments derived from herbaceous branches did not differ and showed reduced fungal contamination (13.75%) and bacterial contamination (0.41%), and high in vitro establishment (91.92%). sodium hypochlorite at 1.5% in the time tested is not efficient in promoting surface disinfestation of nodal segments that already present woody aspects. it is possible to obtain aseptic cultures of e. involucrata for growing shoot apical and nodal segments obtained after the pruning, and sterilized with the aid of mercuric chloride and sodium hypochlorite.
Avalia??o da atividade alelopatica do extrato aquoso de folhas de Eugenia involucrata DC. e Acca sellowiana (O. Berg) Burret
Sausen, Tanise Luisa;L?we, Tatiana Raquel;Figueiredo, Luciano Silva;Buzatto, Cristiano Roberto;
Polibotánica , 2009,
Abstract: a alelopatia é um fen?meno de interferência, mediado por uma intera??o bioquímica entre organismos vegetais, com influência sobre os processos de estabelecimento e forma??o de comunidades vegetais. observa??es a campo demonstram existir baixa regenera??o de espécies no interior de forma??es vegetais conhecidas como matas de mirtáceas, nas quais dominam espécies dessa família, dentre elas acca sellowiana e eugenia involucrata. o objetivo desse trabalho foi avaliar o potencial alelopático de a. sellowiana e e. involucrata, através de bioensaios de germina??o, crescimento e reversibilidade, utilizando lactuca sativa (alface) e solanum esculentum (tomate) como espécies alvo. as sementes e plantulas das espécies alvo foram tratadas com extratos aquosos das folhas das espécies teste em diferentes concentra??es (controle, 25%, 50%, 75% e 100%). os processos de germina??o e de crescimento foram reduzidos com o aumento da concentra??o dos extratos de a. sellowiana e e. involucrata, e a reversibilidade foi observada pelo crescimento da parte aérea. esses resultados apontaram que as espécies avaliadas apresentam potencial alelopático.
Desiccation tolerance and DNA integrity in Eugenia pleurantha O. Berg. (myrtaceae) seeds
Masetto, Tathiana Elisa;Faria, José Marcio Rocha;Davide, Antonio Claudio;Silva, Edvaldo Aparecido Amaral da;
Revista Brasileira de Sementes , 2008, DOI: 10.1590/S0101-31222008000100022
Abstract: the aim of this study was to assess the desiccation tolerance and dna integrity in eugenia pleurantha seeds dehydrated to different moisture contents (mcs). seeds extracted from mature fruits were submmited to drying in silica gel and evaluated at every five percentual points of decrease from the initial mc (35.5%, fresh weight basis). the effects of dehydration on seeds were verified through germination tests and dna integrity assessment. undried seeds achieved 87% germination, value reduced to 36% after being dried to 9.8% mc. when dried slightly more, to 7.4% mc, seeds were no longer able to germinate, suggesting an intermediate behavior in relation to desiccation tolerance. it was observed dna degradation in seeds with 7.4% mc, which might have contributed to the loss of seed germination.
Fracionamento e germina??o de sementes de Eugenia
Silva, Cristiana Vendrame e;Bilia, Denise Augusta Camargo;Barbedo, Claudio José;
Revista Brasileira de Sementes , 2005, DOI: 10.1590/S0101-31222005000100011
Abstract: eugenia involucrata, e. uniflora and e. brasiliensis, tropical tree species from brazil, could be used in forest regeneration, arboriculture and for fruit industrial use. however, seed production is not enough to produce seedlings on a commercial scale. in this study, eugenia involucrata, e. uniflora and e. brasiliensis seeds were evaluated for germination and normal seedling production after cutting. seeds were cut into two parts forming a group with the hilum, a group without hilum and a group with half of the hilum. germination testes were carried out at 30oc using vermiculite as substrate. results showed that when e. involucrata, e. uniflora and e. brasiliensis seeds were cut into two parts, a high percentage of germination was maintained and normal seedlings could be produced. results showed that it would be possible to obtain more than one normal seedling from each seed.
Edson Ferreira Duarte,Ronaldo Veloso Naves,Jácomo Divino Borges,Noga Neve Ribeiro Guimar?es
Pesquisa Agropecuária Tropical , 2007, DOI: 10.5216/pat.v36i3.2043
Abstract: "Cagaita" is a native species of "Cerrado" savannah, with very irregular seed germination. The objective of this study was to evaluate the effect of harvest type and seed size on the germination rate and vigor of Cagaita seeds. The experiment was carried out in a 2 x 3 factorial completely randomized design with six treatments: two harvest types (from the tree and on the ground) and three seed sizes (large, medium, small). Germination started fourteen days after planting and ended in the 60th day. The germination and seedling early growth were described and illustrated by drawings. Large seeds harvest on the ground present lower humidity, greater seedling vigor, and higher fresh matter. There were not found significant differences for germination rate treatments. It was concluded that Cagaita seeds should be obtained from ripe fruits on the ground. Large seeds from those fruits showed to be more vigorous. In seedling production and germination tests the separation of seeds by size may be applied for obtention of seed lots with uniform vigor. KEY-WORDS: Seed, seedling; vigor; morphology; savannah. A Cagaita é uma espécie nativa do cerrado de usos diversos. Contudo, a germina o de suas sementes tem apresentado grande desuniformidade. Este estudo objetivou avaliar os efeitos da forma de coleta dos frutos e do tamanho das sementes sobre a germina o e vigor. O delineamento experimental foi do tipo fatorial 2 x 3, inteiramente casualizado, com dois tipos de coleta dos frutos (na planta e no solo) e três tamanhos das sementes (grandes, medianas e pequenas). A germina o iniciou-se quatorze dias após a semeadura, estabilizando aos sessenta dias após o seu início. As fenofases da germina o e do crescimento inicial das plantulas foram descritas e ilustradas. As sementes grandes coletadas no solo apresentaram menores teores de água e plantulas mais vigorosas, com maior acúmulo de massa fresca. Entretanto, os tratamentos n o apresentaram diferen as significativas na germina o. Concluiu-se que as sementes de cagaita devem, preferencialmente, ser obtidas de frutos maduros caídos sobre a superfície do solo, e que sementes grandes obtidas de frutos coletados no solo s o mais vigorosas. No processo de produ o de mudas e em testes de germina o, a separa o das sementes em diferentes tamanhos pode ser utilizada para obten o de sementes com vigor uniforme. PALAVRAS-CHAVE: Semente; vigor; morfologia; cerrado.
Drying kinetics of jatropha seeds
Siqueira, Valdiney Cambuy;Resende, Osvaldo;Chaves, Tarcísio Honório;
Revista Ceres , 2012, DOI: 10.1590/S0034-737X2012000200004
Abstract: given the necessity of developing jatropha cultivation equipment, this work adjusted different mathematical models to experimental data obtained from the drying of jatropha seeds submitted to different drying conditions and selected the best model to describe the drying process. the experiment was carried out at the federal institute of goiás - rio verde campus. seeds with initial moisture content of approximately 0.50 (kg water/kg dry matter) were dried in a forced air-ventilated oven, at temperatures of 45, 60, 75, 90 and 105°c to moisture content of 0.10 ± 0.005 (kg water/kg dry matter). the experimental data were adjusted to 11 mathematical models to represent the drying process of agricultural products. the models were compared using the coefficient of determination, chi-square test, relative mean error, estimated mean error and residual distribution. it was found that the increase in the air temperature caused a reduction in the drying time of seeds. the models midilli and two terms were suitable to represent the drying process of jatropha seeds and between them the use of the midili model is recommended due to its greater simplicity.
Jorge,Neuza; Moreno L,Débora Maria; Bertanha,Bruna Jorge;
Revista chilena de nutrición , 2010, DOI: 10.4067/S0717-75182010000200010
Abstract: this work aimed to characterize the proximate composition, antioxidant activity and fatty acids profile and tocopherol composition of the oil from eugenia dysenteric a dc seeds. to obtain the extract, the dehydrated and triturated seeds were extracted with ethyl alcohol for 30 minutes, at a proportion of 1:3 of seeds: ethyl alcohol, under continuous agitation at room temperature. afterwards, the mixture was filtered and the supernatant was dehydrated at 40°c in order to determine by direct weighing the dry matter yield of the extract. the "cagaita" seeds showed to be an important source of total carbohydrates, had relevant antioxidant activity and a high content of total phenolic compounds. in comparison to other oils and fats, "cagaita" seeds oil do not constitutes a good source of tocopherols.
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