Recovery and germinative response of Amaranthus deflexus L. seeds under different  levels of water stress and luminosities

The objective of this work was to evaluate, in two experiments, the effect of water stress and luminosity on the germinative behavior and vigor of Amaranthus deflexus L seeds. The seeds were sown in Petri dishes containing two sheets of filter paper moistened with distilled water, in the control treatment. Using this treatment-control configuration, as a standard of comparison, two assays were performed using subsamples from the same A. deflexus seed population. In the first experiment (experiment 1), solutions of polyethylene glycol 6000 (PEG 6000) were used, providing osmotic potentials of -0.3; -0.6; -0.9; -1.2 and -1.5 MPa; however, in the second trial (experiment 2) osmotic potentials of -0.1; -0.2; -0.3; -0.4 and -0.5 MPa were used. At the end of the test, the ungerminated seeds for each treatment were washed and germinated on a filter paper moistened with water. The germination and vigor of the seeds were evaluated through the first germination count, germination test, germination speed index and average germination time. The experimental design was completely randomized, in a 2 x 6 factorial scheme, totaling twelve treatments, with four replicates of 50 seeds each, in both trials. Water stress negatively affects the performance of A. deflexus seeds, reducing germination and vigor from -0.1 MPa. Seed germination was compromised by the absence of light, regardless of the applied stress levels. There was an increase in seed germination after application of the same at higher levels of water stress.

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Does discontinuous hydration of Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S. Irwin & Barneby (Fabaceae) seeds confer tolerance to water stress during seed germination?

Journal of Seed Science ◽

10.1590/2317-1545v40n1182838 ◽

2018 ◽

Vol 40 (1) ◽

pp. 36-43 ◽

Cited By ~ 3

Author(s):

Ayslan Trindade Lima ◽

Paulo Henrique de Jesus da Cunha ◽

Bárbara França Dantas ◽

Marcos Vinicius Meiado

Keyword(s):

Water Stress ◽

Seed Germination ◽

Stress Conditions ◽

Hydration Time ◽

Senna Spectabilis ◽

Mean Germination Time ◽

Polyethylene Glycol 6000 ◽

Osmotic Potentials ◽

Germination Parameters ◽

Hydration And Dehydration

Abstract: Seed hydration memory is the ability of seeds to retain biochemical and physiological changes caused by discontinuous hydration. This study aimed to determine if Senna spectabilis (DC.) H.S. Irwin & Barneby var. excelsa (Schrad.) H.S.Irwin & Barneby (Fabaceae) present seed memory and evaluate the effects of hydration and dehydration cycles (HD) on the seed germination of this species when submitted to conditions of water stress. Seeds underwent HD cycles (0, 1, 2 and 3 cycles) corresponding to the hydration times X (6 hours), Y (16 hours) and Z (24 hours), determined from the imbibition curve, with 5 hours of dehydration and submitted to water stress conditions. Germination was evaluated at 0.0, -0.1, -0.3, -0.6 and -0.9 MPa, obtained with polyethylene glycol 6000 solution. Germinability (%), mean germination time (days) and hydrotime (MPa d-1) were calculated. The seeds of S. spectabilis var. excelsa are sensitive to the low osmotic potentials tested in this study, however, when submitted to the HD cycles of 16 hours hydration (time Y), the tolerance to water stress conditions is increased. In addition, the observed benefits on the evaluated germination parameters show that S. spectabilis var. excelsa present seed hydation memory.

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Water stress in germination, growth and development of coffee cultivars

Journal of Seed Science ◽

10.1590/2317-1545v40n176667 ◽

2018 ◽

Vol 40 (1) ◽

pp. 82-89 ◽

Cited By ~ 2

Author(s):

Julieta Andréa Silva de Almeida ◽

Mary Túlia Vargas Lobato Guedes de Azevedo ◽

Marcus Vinicius Salomon ◽

Priscila Fratin Medina

Keyword(s):

Polyethylene Glycol ◽

Water Stress ◽

Seed Germination ◽

Growth And Development ◽

Coffea Arabica ◽

Primary Root ◽

Control Treatment ◽

Effect Of Water ◽

Reduced Height ◽

Polyethylene Glycol 6000

Abstract: The aim of this study was to evaluate the effect of water stress on the germination of Coffea arabica seeds and the growth and development of plants from these seeds. Seeds of the cultivars Bourbon Vermelho, Mundo Novo, and BA-10 were placed to germinate in the dark at 30 ºC in the presence and absence of 100 g/L of polyethylene glycol 6000. The water stress applied delayed the beginning of seed germination by seven days in relation to seeds of the control, which had achieved responses of up to 50%, but there were no differences between the treatments at the end of the experiment. Furthermore, the length of the primary root in seeds germinated under water stress was less than in the control treatment, especially for the cultivar Mundo Novo. Plants of the cultivars Bourbon Vermelho and Mundo Novo developed from seeds previously germinated under water stress exhibited reduced height and fewer leaf pairs than those from the control, whereas ‘BA-10’ responded in a similar way in both treatments. Thus, the cultivars Bourbon Vermelho and Mundo Novo were more sensitive to the water stress applied in the germination phase than ‘BA-10’.

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Seeds of Caesalpinia echinata Lam. Under Water Stress at Different Temperatures

Journal of Agricultural Science ◽

10.5539/jas.v12n7p66 ◽

2020 ◽

Vol 12 (7) ◽

pp. 66

Author(s):

Caroline Marques Rodrigues ◽

Edna Ursulino Alves ◽

Rosemere dos Santos Silva ◽

Flávio Ricardo da Silva Cruz ◽

Maria Lúcia Maurício da Silva ◽

...

Keyword(s):

Water Stress ◽

Economic Value ◽

Seed Vigor ◽

Large Tree ◽

Randomized Design ◽

Different Temperatures ◽

C 30 ◽

Caesalpinia Echinata ◽

Polyethylene Glycol 6000 ◽

Osmotic Potentials

The Caesalpinia echinata Lam. species, belongs to the Fabaceae family, popularly known as Pau Brazil, is a large tree, native to Brazil, that can be found from Ceará to Rio de Janeiro, with a relevant national historic and economic value. The objective of this study was to evaluate the effects of water stress at different temperatures on germination and seed vigor. The experiment was carried out at the Laboratório de Análise de Sementes of the Centro de Ciências Agrárias of the Universidade Federal da Paraíba, Areia-Paraíba. The water stress was formulated with solutions of polyethylene glycol 6000 (PEG 6000) in different osmotic potentials of 0.0 (control), -0.2; -0.4; -0.6 MPa at constant temperatures of 25, 30 and 35 °C, in a completely randomized design. The percentage of germination, first counting of germination, germination speed index, length and dry matter of seedlings were evaluated to determine the effects of the treatments. Decreases of the osmotic potential negatively influenced the germination and vigor of C. echinata seeds at the three evaluated temperatures (25 ºC, 30 ºC, 35 °C).

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Germination and Emergence of Virginia Buttonweed (Diodia virginiana)

Weed Science ◽

10.1017/s0043174500057830 ◽

1991 ◽

Vol 39 (1) ◽

pp. 37-41 ◽

Cited By ~ 13

Author(s):

James H. Baird ◽

Ray Dickens

Keyword(s):

Water Stress ◽

Seed Germination ◽

Germination Rate ◽

Stress Conditions ◽

Continuous Darkness ◽

Virginia Buttonweed ◽

Osmotic Potentials ◽

Diodia Virginiana

Virginia buttonweed seeds germinated at temperatures between 15 and 40 C, with optimal germination occurring at 25 or 30 C in 12 h light alternated with 15 to 25 or 20 to 30 C in darkness, respectively. Germination rate was lower in continuous darkness than in light. Germination was reduced under simulated water stress conditions with less than 10% of seeds germinating at osmotic potentials below −0.3 MPa. Overall seed germination was reduced under simulated flooding conditions; greater germination occurred in aerated water than in unaerated water. Maximum germination occurred at pH 6. Seedlings emerged from depths as great as 8 cm, with maximum emergence occurring from 2 cm.

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Effect of irrigation by saline magnetized water on seed germination and seedling growth of wheat Triticum aestivum

Baghdad Science Journal ◽

10.21123/bsj.9.2.207-213 ◽

2018 ◽

Vol 9 (2) ◽

pp. 207-213

Author(s):

Baghdad Science Journal

Keyword(s):

Seed Germination ◽

Seedling Growth ◽

Saline Water ◽

Seedling Emergence ◽

Dry Weight ◽

Leaf Length ◽

Control Treatment ◽

Agricultural Improvement ◽

Magnetized Water ◽

Different Levels

The effect of saline magnetized water irrigation on seed germination and seedling growth of wheat cultivar Iraq were studied. Irrigation water was supplemented with different levels of Sodium chloride 6, 12 or 18 mmhos/ cm in addition control treatment, and passed through a proper magnetic felid with 1000, 1250, 1500 or 2000 gaus in addition control treatment. The results showed significantly stimulated shoot development and led to the increase of germination, seedling emergence, area leaf, length of shoot and root and fresh and dry weight compared to the controls. Results also showed significant interaction between saline water and magnetized water. So, using magnetic treatment of saline water could be a promising technique for Agricultural improvement.

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Seed germination of Bowdichia virgilioides Kunth, under water stress

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/s1415-43662001000100021 ◽

2001 ◽

Vol 5 (1) ◽

pp. 115-118 ◽

Cited By ~ 9

Author(s):

Lígia M. de M. Silva ◽

Ivor B. de Aguiar ◽

Teresinha de J.D. Rodrigues

Keyword(s):

Water Stress ◽

Seed Germination ◽

Sulphuric Acid ◽

Stress Resistance ◽

Water Availability ◽

Tree Species ◽

Native Tree ◽

Drought Conditions ◽

Native Tree Species ◽

Osmotic Potentials

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 inhibited, but was restored with an increase of water availability.

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Water stress and temperature on germination and vigor of Handroanthus impetiginosus (Mart. ex DC)

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v22n5p349-354 ◽

2018 ◽

Vol 22 (5) ◽

pp. 349-354

Author(s):

Paulo C. S. Santos ◽

Clarisse P. Benedito ◽

Tatianne R. C. Alves ◽

Emanoela P. Paiva ◽

Erivanessa C. Sousa ◽

...

Keyword(s):

Water Stress ◽

Seed Germination ◽

Abiotic Factors ◽

Primary Root ◽

Seed Vigor ◽

Physiological Processes ◽

Different Temperatures ◽

Osmotic Agent ◽

Osmotic Agents ◽

Osmotic Potentials

ABSTRACT Water availability and temperature are among the main abiotic factors that influence seed germination and vigor, since they act directly on biochemical and physiological processes, which result in the production of the primary root. The objective of this study was to verify the effects of stress on germination and vigor of H. impetiginosus (‘ipê-roxo’) seeds under different temperatures and osmotic agents. The experimental design was completely randomized, in a 6 x 2 factorial scheme (osmotic potentials x temperatures) with four replicates of 25 seeds for each osmotic agent. In order to simulate water stress, polyethylene glycol (PEG 6000) and mannitol solutions were used and distilled water was used as control. Osmotic potentials of 0, -0.2, -0.4, -0.6, -0.8 and -1.0 MPa were evaluated at temperatures of 25 and 30 °C, under 8 h photoperiod. The variables analyzed were: germination, germination speed index, shoot length, root length, and total dry matter of seedlings. Simulated water stress affected seed germination and seed vigor of H. impetiginosus at both temperatures and osmotic agents from -0.6 MPa.

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Effet d’un assèchement édaphique sur la croissance, l’allocation de biomasse et les relations hydriques chez Casuarina glauca

Botany ◽

10.1139/b08-069 ◽

2008 ◽

Vol 86 (11) ◽

pp. 1242-1251 ◽

Cited By ~ 1

Author(s):

Zoubeir Béjaoui ◽

Ali Albouchi ◽

Mohammed S. Lamhamedi ◽

Mohamed Hédi El Aouni

Keyword(s):

Water Stress ◽

Water Relations ◽

Dry Mass ◽

Control Treatment ◽

Severe Stress ◽

Drought Period ◽

Casuarina Glauca ◽

Stress Treatment ◽

A Cell ◽

Osmotic Potentials

Tunisia has vast land tracts that are marginal, arid, semiarid, or desert (about three quarters of the surface of the country). Reforestation of these regions is one of the methods being used to rehabilitate degraded areas. Casuarina glauca Sieber, a fast-growing tree species that is widely used outside of its native range, was tested in the present study with respect to its degree of acclimatization and hardening in response to drought. Three water regimes, simulating the conditions of the reforestation sites, were applied to C. glauca seedlings. These regimes included a control treatment (T : predawn water potential Ψb = –0.2 MPa), a moderate stress treatment (M : Ψb = –0.5 MPa), and a severe stress treatment (S : Ψb = –1.0 MPa). Water relations parameters, estimated by pressure–volume curves through a repeat pressurization method, as well as accumulated dry mass were measured at the beginning of the experiment and 2, 4, and 6 months following treatment imposition. The total dry mass of M and S plants was significantly affected by the treatments. However, water stress favoured dry mass allocation to roots and decreased the shoot turgid mass / dry mass ratio (TM/DM). The evolution of water relations parameters under M or S regimes revealed an adaptive capacity of C. glauca seedlings, as expressed by a significant decrease of the osmotic potentials at full turgor (Ψπ100) and at the turgor loss point (Ψπ0), an osmotic adjustment in water-stressed plants reaching 0.31 and 0.56 MPa, and a significant increase in εmax reaching 26 % and 68 % of that of the control plants, respectively, at the end of the drought period. A reduction in shoot TM/DM combined with increases in εmax during water stress suggests the presence of a cell wall adjustment. These effects were more pronounced under the severe stress. Our results suggest that preconditioning seedlings to drought under nursery conditions by applying a moderate or severe stress, depending on the conditions of the planting site, for 4 months prior to outplanting, possibly will allow the seedlings to adapt morphologically and physiologically and improve their chance of survival in arid and semiarid zones.

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Mobilization of reserves and germination of seeds of Erythrina velutina Willd. (Leguminosae - Papilionoideae) under different osmotic potentials

Revista Brasileira de Sementes ◽

10.1590/s0101-31222012000400008 ◽

2012 ◽

Vol 34 (4) ◽

pp. 580-588 ◽

Cited By ~ 6

Author(s):

Renata Conduru Ribeiro Reis ◽

Bárbara França Dantas ◽

Claudinéia Regina Pelacani

Keyword(s):

Water Stress ◽

Seed Germination ◽

Osmotic Potential ◽

Soluble Sugars ◽

Germination Percentage ◽

Uniformity Coefficient ◽

Carbon And Nitrogen ◽

Germination Process ◽

Mean Time ◽

Osmotic Potentials

Some environmental factors, including water availability, may influence seed germination. This study investigated the germination of E. velutina seeds submitted to different osmotic potentials and mobilization of reserves during water-stress. Scarified seeds were arranged in paper rolls and soaked in solutions of Polyethylene Glycol (PEG) prepared in osmotic potentials 0.0, -0.2, -0.4, -0.6, and -0.8 MPa and kept into a seed germinator, at 25 °C, and 12/12 h photoperiod (L/D), during 10 days. The percentage, mean time, mean speed, germination speed index; as well as the germination uniformity coefficient were assessed. During germination process the total soluble sugars, reducing sugars, soluble protein, and total amino acids were quantified in the cotyledon, hypocotyl and radicle of soaked seeds and cotyledons of quiescent seeds (control). There was influence of osmotic potential on E. velutina seed germination. The germination percentage remained at high levels until -0.6 MPa and above this osmotic potential there has been no germination. The mobilization of stored reserves of carbon and nitrogen in E. velutina seeds was also influenced by water-stress. There was sensitiveness between -0.2 and -0.6 MPa; however, the degradation and the mobilization of reserves was slower when the osmotic potential decreased.

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Salicylic acid in the physiological priming of onion seeds subjected to water and salt stresses

Revista Brasileira de Engenharia Agrícola e Ambiental ◽

10.1590/1807-1929/agriambi.v23n12p919-924 ◽

2019 ◽

Vol 23 (12) ◽

pp. 919-924 ◽

Cited By ~ 1

Author(s):

José E. S. B. da Silva ◽

Emanoela P. de Paiva ◽

Moadir de S. Leite ◽

Salvador B. Torres ◽

Maria L. de Souza Neta ◽

...

Keyword(s):

Salicylic Acid ◽

Salt Stress ◽

Water Stress ◽

Dry Matter Accumulation ◽

Randomized Design ◽

Allium Cepa L ◽

Onion Cultivar ◽

Completely Randomized Design ◽

Polyethylene Glycol 6000 ◽

Osmotic Potentials

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 at concentrations of 0 and 50 µM and the osmotic potentials of 0, -0.3, -0.6 and -0.9 MPa induced by NaCl), in four repetitions of 50 seeds. For both experiments, germination, growth and accumulation of organic solutes were evaluated. Salicylic acid did not stimulate the germination of onion seeds in the absence of stress, but the application of 50 µM of salicylic acid increased the germination speed, growth and dry matter accumulation under conditions of water and salt stress. Onion plants were efficient in performing osmotic adjustment up to the potentials of -0.2 MPa induced by PEG 6000 under water stress and of -0.4 MPa induced by NaCl under salt stress.

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