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Correla??o entre testes de vigor em sementes de maxixe
Torres, Salvador Barros;Silva, Magnólia Aparecida Silva da;Carvalho, Ione Maria Soares de;Queiróz, Manoel Abílio de;
Pesquisa Agropecuária Brasileira , 1999, DOI: 10.1590/S0100-204X1999000600020
Abstract: this work was carried out with the objective of comparing the efficiency of different tests in the physiological quality of gherkin seeds (cucumis anguria l.), looking for information for a better utilization of these quality control tests, as well as verifying their relation at field emergency. seven lots of gherkin seeds were evaluated by the germination test, first count, electrical conductivity at 4 and 24 hours, accelerated aging, controlled damage, cold without soil, and field emergency. the trials were carried out at the seed lab and at an experimental field of embrapa-cpatsa, at petrolina, pe, brazil, from january to may 1996. in the lab tests, a completely randomized design was used, and in the field tests, a randomized block design was used - both of them with four repetitions of fifty seeds, being the means compared by the tukey test, at 1% of probability. the germination and vigor tests were effective to detect differences of physiological quality among gherkin seed lots. the damage control and cold without soil tests were more stable on the division of the lots by the vigor levels and, at the same time, showed the highest correlation with field emergency.
Condicionamento osmótico de sementes de algod o e seus efeitos na germina o e vigor. = Osmotic conditioning of cotton seeds and its effect on germination and vigor.
Vicente de Paula Queiroga,José Maria Durán,José Wellington dos Santos,Diego Antonio Nóbrega Queiroga
Agro@mbiente On-line , 2008,
Abstract: O objetivo do trabalho foi avaliar o efeito do condicionamento osmótico na qualidade fi siológica de sementes de algod o herbáceo. Os ensaios foram realizados no Laboratório de Fitotecnia da Universidade Politécnica de Madrid, Espanha, em 2006. Foram realizados dois ensaios: sementes submetidas às solu esosmóticas de PEG 6000 (-0,25 MPa) e de nitrato de potássio (0,3 M) nos sete tempos de condicionamento osmótico (0, 12, 24, 36, 48, 72 e 96 h) à temperatura de 20 oC. As variáveis analisadas foram porcentagem de germina o e comprimento de plantulas. As sementes foram tratadas com hipoclorito de sódio (3%) e captan 50 antes de serem postas para germinar em camara de germina o com temperatura de 25 oC. O delineamento experimental utilizado foi inteiramente ao acaso, em esquema fatorial com quatro repeti es. As solu es osmóticas de PEG e nitrato de potássio n o foram favoráveis à germina o das sementes, todavia o vigor das sementes foi incrementado por ambas as solu es osmóticas em algumas condi es estudadas. = The objective of this study was to evaluate the effects of the osmotic conditioning on the physiological quality of seeds of herbaceous cotton. The assays were realized in the Laboratory of Phytotech of the Polytechnical University of Madrid, Spain, in 2006. Two assays were done: one with seeds submitted to osmotic solutions of PEG 6000 (-0,25 MPa) and the other to potassium nitrate (0,3 M) during seven periods of osmotic conditioning (0, 12, 24, 36, 48, 72 and 96 h ) at a temperature of 20 oC. The analyzed variables were calculated as percentage of the germination and length of seedlings. The seeds were pre-treated with Sodium hypochlorite (3%) and 50 Captan before being placed to germinate in germination chambers at a temperature of 25 oC. The adopted experimental delineation was arranged as completely randomized with four replications, having treatments in the factorial project. The osmotics solutions of PEG and potassium nitrate were not favorable to the germination of the seeds, however the vigor of the seeds was developed by both the osmotics solutions in some conditions evaluated.
Efeitos do condicionamento fisiológico e da secagem na germina??o e no vigor de sementes de cenoura
Balbinot, Ernando;Lopes, Higino Marcos;
Revista Brasileira de Sementes , 2006, DOI: 10.1590/S0101-31222006000100001
Abstract: seed priming was evaluated under different technologies including the immersion of seeds in solutions with oxygen supply, followed or not by drying processes. the objectives of this study were to evaluate the effects of osmotic conditioning on systems with oxygen supply followed by drying on the germination and the vigor in carrot seeds, cv. "brasilia". the seeds were submerged in 40ml distilled water and peg 6000 solutions at 161,30 and 240,97g.l-1 corresponding, respectively, to the osmotic potentials of -0,4 and -0,8mpa, at 15oc, with oxygen supply, during 12, 24 and 48 hours. the seeds were dried in an oven at 35oc, with air circulation for 1, 2, 3, 4, and 5 hours and seed moisture content was determined. the effects of the osmotic conditioning and drying were evaluated by the germination test, first count of the germination test, seedling vigor classification, seedling length and mass and electrical conductivity. the seed moisture content decreased linearly with the time when submitted to the drying process. osmoconditioning followed by seed drying did not affect the germination and contributed to increasing the seed vigor in relation to non osmoconditioned seeds.
Viabilidade e vigor de sementes de paineira após armazenamento, condicionamento e estresses salino e térmico
Perez, Sonia Cristina Juliano Gualtieri de Andrade;Jardim, Manoela Meyrsieck;
Pesquisa Agropecuária Brasileira , 2005, DOI: 10.1590/S0100-204X2005000600009
Abstract: the aim of this work was to evaluate the effects of priming, salt and thermal stress on viability and vigor of folk silk tree seeds (chorisia speciosa st.-hil) after storage in hermetic containers at 5oc. intact and with coat punction seeds were primed in distilled water and kno3 solutions (0.1 m and 0.2 m) during 24 hours at 27oc. salt stress was simulated with nacl solutions at different osmotic potential, ranging from 0.0 mpa until -1.2 mpa, at 27oc. different intensities of thermal stress were applied on dried seeds; germination tests were carried out at 27oc. as the intensity of salt and thermal stress increased, a reduction on seed vigor and viability was recorded in intact or punctured seeds. the salt tolerance limit showed before the storage was not reduced in intact seeds but there was an increase at thermal sensibility on intact or punctured seeds. the highest rates and germination percentage are recorded in seeds primed in water, submitted to salt and thermal stress. the conductivity test indicated the seeds primed in water or kno3 0.1 m as the most vigorous. it is desirable to use priming to substitute the coat punction, after seed storage.
Efeito do condicionamento osmótico na germina??o e vigor de sementes de sorgo com diferentes qualidades fisiológicas
Oliveira, Alexandre Bosco de;Gomes-Filho, Enéas;
Revista Brasileira de Sementes , 2010, DOI: 10.1590/S0101-31222010000300003
Abstract: the objective of this study was to evaluate the effect of osmotic conditioning on the germination and vigor of sorghum seeds with different physiological qualities from the ipa 1011 cultivar. the experimental design was completely randomized with four replications in a factorial 2 x 2, consisting of four treatments: 1. aged seeds, 2. seed not aged, 3. seeds aged and conditioned osmotically and 4. seeds not aged and conditioned osmotically. the seeds quality was evaluated from the water content (wc), mass of thousand seeds (mts), the first germination count (fgc) standart germination test (sgt), germination speed index (gsi), germination mean time (gmt ), accelerated aging test (aat), cold test (ct), electrical conductivity test (ect) and leaching of potassium test (lpt). the results showed that artificial aging negatively affects the performance of sorghum seeds and such effects can be partially reversed by priming. this technique does not influence germination but further benefits vigor in physiologically superior and inferior seeds.
Germina o de sementes de alface submetidas a condicionamento osmótico durante o armazenamento  [cached]
Fessel Simone Aparecida,Vieira Roberval Daiton,Rodrigues Teresinha de Jesus Deléo,Fagioli Marcelo
Scientia Agricola , 2002,
Abstract: Em algumas espécies a técnica do condicionamento osmótico permite a obten o de uma germina o rápida e uniforme. A pesquisa teve por objetivo verificar a eficiência do condicionamento osmótico de sementes de alface sobre a sua germina o. Sementes dos cultivares Mesa 659, Nabuco RS e Ver nica, com dois níveis de viabilidade, foram submetidas ao condicionamento osmótico em solu o (0,35 mol) de manitol por períodos de 3, 4, 5 e 6 dias sob 20oC e em presen a de luz. A seguir, as sementes foram submetidas à secagem (32oC) por 12 horas em estufa com circula o de ar. As avalia es foram feitas pelo teste padr o de germina o aos 0, 10, 20, 30, 60 e 90 dias após o condicionamento e secagem das sementes. Utilizou-se o delineamento experimental inteiramente casualizado, com quatro repeti es de 50 sementes, em esquema fatorial 2 × 5× 6, (dois níveis de vigor; cinco períodos de condicionamento osmótico e seis períodos de armazenamento após secagem). A resposta de sementes de alface ao condicionamento osmótico varia em fun o do cultivar e do período de condicionamento osmótico.
Efeitos da giberelina e da secagem no condicionamento osmótico sobre a viabilidade e o vigor de sementes de sementes de mam?o (Carica papaya L.)
Lopes, Higino Marcos;Souza, Cleiton Mateus;
Revista Brasileira de Sementes , 2008, DOI: 10.1590/S0101-31222008000100023
Abstract: the objective of this study was to evaluate the effects of the presence or absence of gibberellic acid in the conditioning solution and drying, before and after osmotic conditioning, on papaya seed viability and vigor. the seeds were placed in solutions of peg-6000 at -0.1 mpa, -1.0 mpa and in distilled water with two levels of ga3, 0 or 200 mg.l-1. a completely randomized experimental design with four replications in a 3 x 2 + 2 factorial design was employed with three combinations of conditioning and drying: 1. seeds conditioned after extracted from fruit, with 67.0% moisture content; 2. dry seeds (11.5%) and conditioned; and 3. dry seeds conditioned and redried to 11.5%, with two levels of ga3 (0 and 200 mg.l-1). two additional treatments, both without conditioning, one using seeds with 67% moisture content and another with dry seeds with 11.5% moisture content were also tested. moisture content (%), germination at 14, 21 and 28 days (%), electrical conductivity (μs/cm/g), seedling dry weight (g) and seedling length (mm) were evaluated. the seeds conditioned in lower osmotic potential solution and in the presence of gibberellic acid improved the papaya seed germination. drying the conditioned seeds decreased the seed vigor and the viability, regardless of presence or absence of gibberellic acid.
Qualidade fisiológica e potencial de armazenamento de sementes de tomate submetidas ao condicionamento osmótico  [cached]
Rossetto Claudia Antonia Vieira,Lima Tatiana de Moraes,Nakagawa Jo?o
Horticultura Brasileira , 2002,
Abstract: Considerando a necessidade de verificar os efeitos de tratamentos de condicionamento osmótico na qualidade fisiológica e no potencial de armazenamento, foram avaliados três lotes comerciais de sementes de tomate representados pelos cultivares Quadrado Mix, Calmec VFN e Topmec. As sementes foram classificadas por peneiras de crivo circular de diametros de 3,5 e 4,7 mm, passando cada lote a constituir um sublote e, em seguida, foram submetidas ao condicionamento osmótico. O delineamento experimental foi inteiramente casualizado em fatorial 2x5x6 (condicionamento osmótico x sublote), com quatro repeti es, por período de armazenamento. Por tratamento, as sementes foram imersas em solu es aeradas de polietileno glicol, a 0,0 e -1,0 MPa, por sete dias, a 20oC. As avalia es da qualidade fisiológica foram realizadas imediatamente após o condicionamento e aos 30; 60; 90 e 120 dias de armazenamento em potes plásticos e em condi es de camara fria. Os resultados permitiram concluir que imediatamente após o tratamento e até 60 dias de armazenamento, as sementes condicionadas apresentaram maior germina o e vigor, independente do sublote. Porém, após 120 dias de armazenamento, as sementes da cultivar Quadrado Mix, que foram condicionadas, apresentaram maior germina o e vigor, do que as sementes n o condicionadas.
Qualidade de sementes de algod o submetidas ao condicionamento hídrico. = Physiological quality of cottonseeds submitted to hydric conditioning.
Vicente de Paula Queiroga,José Maria Durán,José Wellington dos Santos,Diego Antonio Nóbrega Queiroga
Agro@mbiente On-line , 2009,
Abstract: No presente trabalho se determinou os efeitos dos tratamentos pré-germinativos de hidrata o sobre a germina o e vigor de sementes de algod o. Um ensaio foi conduzido no Laboratório de Fitotecnia da Universidad Politécnica de Madrid, Espanha, no período de mar o a setembro de 2006. Utilizou-se sementes deslintadas quimicamente da cultivar Panton e aplicou-se dois tipos de condicionamento hídrico: sem e com renova o de água, em fun o dos tempos de imers o de 0, 1, 2, 4, 8 e 24 horas. As sementes de algod o da cultivar Panton foram provenientes dos campos irrigados de produ o de sementescertifi cadas da empresa Monsanto de Sevilla, Espanha.Os resultados indicam que o condicionamento hídrico foi mais efetivo para incrementar o vigor das sementes de algod o, mas n o foi eficiente para elevar seu potencial germinativo. = The present study determined the effects of daily pre-germinative hydration treatments on the germination and vigor of cottonseeds. The assay was realized in the Laboratory of Phytotech of the Universidad Politécnica de Madrid, Spain, the period from March to September 2006. Delinted seeds of the cultivar Panton were used and were submitted to two types of chemical hydric conditions: with and without water renewal, in function of the periods of immersion 0, 1, 2, 4, 8 and 24 hours.The seeds of cotton cultivar Panton were from the irrigated fields of production of certifi ed seeds from Monsanto, Seville, Spain. The results indicated that hydric conditioning was more effective for the development the vigor of cottonseeds, but were not efficient to elevate its germinative potential.
Condicionamento osmótico em sementes de cebola: I. efeitos sobre a germina o  [cached]
Trigo Maria Fernanda Otero Otumuro,Nedel Jorge Luiz,Trigo Luis Felipe Navia
Scientia Agricola , 1999,
Abstract: Lotes de sementes de cebola, cultivares Aurora e Petrolini, de diferentes níveis de vigor, foram osmocondicionados utilizando solu es aquosas de KNO3 e de PEG, nos tempos de embebi o de 0 (controle), 24 e 48 horas, à temperatura de 20°C e com aera o constante. Após os tratamentos as sementes foram secas em estufa a 30°C até atingirem os níveis iniciais de umidade, em seguida foi efetuada uma divis o das sementes em por es iguais: uma foi armazenada em sacos de papel no interior de um dessecador por seis meses e a outra foi submetida imediatamente as avalia es em laboratório. Os resultados mostraram que a velocidade e a percentagem total de germina o sob condi es de estresse aumentaram nas sementes de cebola osmocondicionadas. As sementes osmocondicionadas com solu es aeradas de KNO3 por 24 horas apresentaram melhor desempenho. O condicionamento osmótico pode reverter o processo de envelhecimento natural de sementes de cebola. Sementes de cebola osmocondicionadas mantiveram sua viabilidade por seis meses de armazenamento.
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