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| Registros recuperados: 25 | |
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| García Ruiz, Mayra Teresa. |
| Se evaluaron los cambios de acidez titulable a lo largo de 24 h, de las yemas vegetativas con longitud media de 0.5 cm y nopalitos de 6 y 11 cm, de Opuntia ficus-indica de los cultivares Atlixco, Copena V1, Milpa Alta, Moradaza y Solferino, con riego. También se evaluó el efecto de la disminución del potencial de agua (ΨA) del suelo, por suspensión del riego durante 60 días, en condiciones de invernadero, en el potencial osmótico (ΨS ), liberación de electrolitos (o índice de daño membranal, Id) y contenido de polisacáridos estructurales de los nopalitos de esos cinco cultivares y una recolecta silvestre de O. streptacantha. La acidez de las yemas vegetativas y los nopalitos fluctuó entre 0.2 y 0.9 % a lo largo de las 24 horas del día, con las... |
| Tipo: Tesis |
Palavras-chave: Acidez titulable; Potencial hídrico; Potencial osmótico; Polisacáridos; Maestría; Fisiología Vegetal; Tritable acidity; Water potential; Osmotic potential; Polysaccharides. |
| Ano: 2007 |
URL: http://hdl.handle.net/10521/1654 |
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| XIONG,RC.; MA,Y.; WU,HW.; JIANG,WL.; MA,XY.. |
| ABSTRACT: Velvetleaf, an annual broadleaf weed, is a common and troublesome weed of cropping systems worldwide. Laboratory and field experiments were conducted to determine the effects of environmental factors on germination and emergence of velvetleaf. Seeds germinated over a range of constant temperatures from 10 to 40 oC regardless of light conditions, but no germination occurred at temperature below 5 oC and beyond 50 oC. Seeds germinated at alternating temperature regimes of 15/5 to 40/30 oC, with maximum germination (>90%) at alternating temperatures of 40/30 oC. Germination was sensitive to water stress, and only 0.4% of the seeds germinated at the osmotic potential of -0.4 MPa. There was no germination at ? 0.6 MPa. Moreover, germination was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Burial depth; Light; Osmotic potential; Saline and alkaline stress; Temperature. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100321 |
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| Sohrabi Kertabad,S.; Rashed Mohassel,M.H.; Nasiri Mahalati,M.; Gherekhloo,J.. |
| Lesser celandine (Ranunculaceae) is a perennial weed with tuberous root. Tubers are the most important means of reproduction and dispersion of this weed. In recent years, it has spread into wheat fields in Western Iran, mainly in the Lorestan province. A series of experiments were conducted to determine cardinal temperatures and to study the effects of pre-chilling, temperature fluctuations, tuber size, freezing and drying on germination of the tubers, as well as the effect of planting depth on sprouting of the tubers. The results obtained showed that the highest percentage of germination occurred when tubers were stored for more than 2 weeks at 4 or 8 ºC. The optimum temperature for germination differed in large and small tubers (8 and 14oC,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Freezing; Germination; Osmotic potential; Tuberous root. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000300010 |
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| Sohrabikertabad,S.; Ghanbari,A.; Mohassel, Mohamad,H.R.; Mahalati,M.N.; Gherekhloo,J.. |
| Smellmelon, an annual invasive weed of soybean production fields in the north of Iran, reproduces and spreads predominately through seed production. This makes seed bank survival and successful germination essential steps in the invasive process. To evaluate the potential of Smellmelon to invade water-stressed environments, laboratory studies were conducted to investigate the effect of desiccation and salinity at different temperatures on seed germination and seedling growth of Cucumis melo. Seeds were incubated at 25, 30, 35 and 40 ºC in the darkness in a solution (0, -0.2, -0.4, -0.6, -0.8, 1 and 1.2 MPa) of a salt (NaCl), and in a solution (0, -2, -4, -6, -8, -10, -12 bar) of PEG-6000 (Polyethylene glycol), in two separate experiments. The results... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Germination; Osmotic potential; Cucurbitaceae; Seedling vigor index (SVL). |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000400009 |
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| Derakhshan,A.; Gherekhloo,J.. |
| Specific knowledge about the dormancy, germination, and emergence patterns of weed species aids the development of integrated management strategies. Laboratory studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of Cyperus difformis. Germination of freshly harvested seeds was inhibited by darkness; however, when seeds were subsequently transferred to complete light they germinated readily. Our results showed that 2 wk of cold stratification overcome the light requirement for germination. Seeds of C. difformis were able to germinate over a broad range of temperatures (25/15, 30/20, 35/25, and 40/30 ºC day/night). The response of germination rate to temperature was described as a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Osmotic potential; Salinity stress; PH; Soil depth; Temperature. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582013000400008 |
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| WANG,Y.H.; MA,Y.L.; FENG,G.J.; LI,H.H.. |
| ABSTRACT: Large crabgrass is one of the worst exotic weed in tropical, subtropical, and temperate regions of the world. In this study, the abiotic factors affecting seed germination and early seedling emergence of large crabgrass were investigated under laboratory conditions. The optimum temperatures of germination occurred at the range from 25 to 35 oC under 12 h light/12 h dark condition. Some seeds could germinate in the dark, but light exposure significantly stimulated the germination. Large crabgrass seed was tolerant to salinity level range of 0 to 160 and low water potential (11% germination at -0.8 MPa). Medium pH had no significant effect on seed germination and more than 90% seeds germination was obtained over a broad pH range from 4.0 to 10.0.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Temperature; Light; Osmotic potential; Heat-shock; Burial depth. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582018000100268 |
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| DONG,H.; MA,Y.; WU,H.; JIANG,W.; MA,X.. |
| ABSTRACT: Solanum nigrum L. (black nightshade), an annual to short-lived perennial weed, has become a problem weed in farming systems in central China. Laboratory and greenhouse experiments were conducted to examine the influence of various abiotic factors on seed germination of black nightshade to develop effective weed control programs. Seeds germinated at a range of constant temperatures from 15 to 30 oC, but no germination occurred at temperatures below 10 oC or above 35 oC. Seeds also germinated at alternating temperature regimes from 15/5 to 40/30 oC, with maximum germination (> 93.5%) at the alternating temperatures of 25/15 and 30/20 oC. Germination decreased as osmotic potential became more negative, and no germination was observed at ≤ -0.8... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Burial depth; Light; Osmotic potential; Saline and alkaline stress; Seed biology; Temperature. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-83582020000100245 |
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| Silva,José E. S. B. da; Paiva,Emanoela P. de; Leite,Moadir de S.; Torres,Salvador B.; Souza Neta,Maria L. de; Guirra,Keylan S.. |
| ABSTRACT This study aimed to evaluate the effect of physiological priming with salicylic acid on the mitigation of water and salt stresses on onion (Allium cepa L.) seeds. For this, seeds of onion, cultivar IPA 11, were soaked in salicylic acid solution (50 µM) for 24 h and placed to germinate at different water and saline potentials. For water stress, the experiment was conducted in a completely randomized design, in a 2 x 5 factorial scheme (salicylic acid with 0 and 50 µM and osmotic potentials of 0, -0.1, -0.2, -0.3, -0.4 MPa induced by polyethylene glycol 6000), with four repetitions of 50 seeds per plot. In salt stress, the adopted experimental design was completely randomized, with treatments distributed in a 2 x 4 factorial scheme (salicylic acid... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allium cepa; Mitigator; Water deficit; Osmotic potential. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662019001200919 |
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| Silva,Lígia M. de M.; Aguiar,Ivor B. de; Rodrigues,Teresinha de J.D.. |
| Bowdichia virgilioides (Leguminosae-Papilionoideae) is a native tree species in Brazil characteristic of the savannah vegetation. Seeds of this species were submitted to different osmotic potentials induced by polyethyleneglycol (PEG-6000) in order to verify their resistance to drought conditions. Seeds were previously scarified with sulphuric acid and incubated at 25 ºC with an eight hours photoperiod, at osmotic potentials of 0.0, -0.1, -0.3, -0.5, -0.7, -0.9 and -1.1 MPa. It was found that water stress resistance limit ranged from -0.7 to -0.9 MPa. Significant reduction in germination velocity from -0.3 MPa, and final percentage of germination from -0.5 MPa in relation to control, were observed. Germination under drastic conditions of water stress was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Forest seed; Physiological quality; Osmotic potential; Polyethyleneglycol. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662001000100021 |
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| Paiva,Emanoela P. de; Sá,Francisco V. da S.; Torres,Salvador B.; Brito,Marcos E. B.; Moreira,Romulo C. L.; Silva,Luderlândio de A.. |
| ABSTRACT The objective of this study was to evaluate the tolerance of cowpea cultivars to water stress, during seed germination and seedling establishment. For this, a completely randomized experimental design was used in a factorial scheme consisting of nine cultivars of cowpea (BRS Guariba, BRS Potengi, BRS Itaim, BRS 17 Gurguéia, BRS Aracê, Paulistinha, Maratanã, Costela-de-Vaca and Canapu-Branco) and two levels of osmotic potential induced by PEG 6000 (0.0 MPa (control) and -0.4 MPa) in four replicates of 50 seeds. The variables analysed were germination, germination first count, root and shoot lengths, and dry matter accumulation of shoots and roots. The dissimilarity between the genotypes was also determined by Euclidean distance. Germination and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Initial growth; Polyethylene glycol; Osmotic potential. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662018000600407 |
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| Pereira,Isabella C.; Catão,Hugo C. R. M.; Caixeta,Franciele. |
| ABSTRACT The aim of this study was to evaluate seed physiological quality and initial pea (Pisum sativum) seedling development at different water and salt potentials. Polyethylene glycol 6000, sodium chloride and potassium chloride solutions with different osmotic potentials (0; -0.2; -0.4; -0.6; -0.8; -1.0, and -1.2 MPa) were used, and the experiment had a 3 × 7 factorial arrangement. The physiological quality and initial seedling growth characteristics (first germination count, final germination count, strong normal seedlings, epicotyl and taproot lengths, epicotyl dry matter, and root dry matter) were evaluated in a completely randomized experimental design, with four repetitions. Decreases in the observed variables showed that the simulated stress... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Pisum sativum; Vegetable; Polyethylene glycol; Osmotic potential. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662020000200095 |
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| Oliveira,Wanderson J. de; Souza,Edivan R. de; Almeida,Brivaldo G. de; Silva,Ênio F. de F. e; Melo,Hidelblandi F. de; Leal,Lucas Y. C.. |
| ABSTRACT The study of the water energetic status under saline condition and its impact on the development of cowpea is of extreme importance, since this crop is the food base in many parts of the world. An experiment was carried out in a greenhouse from March to May 2014 using the cultivar IPA 206 in Fluvisol collected in the municipality of Pesqueira, PE, Brazil. Waters with six levels of electrical conductivity (0; 2.5; 5; 7.5; 10; 12.5 dS m-1) formulated with NaCl and a salt mixture were used. The experiment was conducted in randomized blocks in a 6 x 2 factorial arrangement with four replicates, forming 48 experimental plots. The matric, osmotic and total potential of water in the soil, the osmotic, and water potential in the plant and atmospheric... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water potential; Osmotic potential; Vigna unguiculata. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016000800685 |
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| Oliveira,Fabrícia N. de; Oliveira,Jessica R. de; Torres,Salvador B.; Freitas,Rômulo M. O. de; Nogueira,Narjara W.. |
| ABSTRACT The germination of seeds is affected by many factors, including water availability and temperature. This study aimed to evaluate the effects of water stress and different temperatures on germination and initial development of S. gardneriana M. R. Barbosa & Peixoto seedlings. The experiment was carried out in a completely randomized design, in a 7 x 4 factorial scheme, with seven potentials (0; -0.1; -0.2; -0.3; -0.4; -0.5 and - 0.6 MPa) and four temperatures (25, 30, 35 and 20-30 °C), with four replicates of 25 seeds. The analyzed variables were germination, percentage of normal seedlings, germination speed index, seedling length (shoot and root) and dry weight (shoot and root). There is a decrease in the germination and vigor of the seeds as... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Rubiaceae; Caatinga; Osmotic potential; Forest species. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662017000500333 |
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| Santos,Patricia Menezes; Cruz,Pedro Gomes da; Araujo,Leandro Coelho de; Pezzopane,José Ricardo Macedo; Valle,Cacilda Borges do; Pezzopane,Cristiana de Gaspari. |
| Two cultivars of Brachiaria brizantha (Hochst ex. A. Rich) Stapf. (Syn. Urochloa) were evaluated for their adaptation to water deficit and the stress response mechanisms in a greenhouse experiment. The experimental design was in completely randomized blocks with a 2 × 2 × 4 factorial arrangement. The Marandu and BRS Piatã cultivars were evaluated under two water availability conditions, with or without water restriction. The harvests were carried out 0, 7, 14 and 28 days after the start of water restriction. For both cultivars, the water deficit stress caused a reduction in shoot biomass and leaf area and an increase in the percentage of roots in the deeper soil layers. The B. brizantha cv. Marandu reached critical levels of leaf water potential in a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: BRS Piatã; Marandu; Osmotic potential; Water availability; Water potential. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982013001100001 |
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| Leal,Caio César Pereira; Torres,Salvador Barros; Dantas,Nadjamara Bandeira de Lima; Aquino,Gutierres Silva Medeiros; Alves,Tatianne Raianne Costa. |
| ABSTRACT Combretum leprosum Mart., commonly known as ‘mofumbo’, is used for medicinal purposes, recovery of degraded areas and apiculture. The objective of this study was to evaluate the effect of water stress on the germination and vigor of C. leprosum seeds as function of different temperatures. To compose the treatments, the substrate used was paper roll moistened with polyethylene glycol solutions (PEG 6000), at the following levels of osmotic potential: 0.0; -0.1; -0.2; -0.2; -0.4; and -0.5 MPa, and placed in chamber at constant temperatures of 25, 30 and 35 and alternating temperature of 20-30 °C, forming a 6 x 4 factorial. The seeds were submitted to the following evaluations: germination percentage, germination speed index, root length, shoot... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Combretaceae; Osmotic potential; Abiotic stress. |
| Ano: 2020 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902020000100413 |
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| Registros recuperados: 25 | |
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