Physiological potential of Phaseolus lunatus L. seeds subjected to water stress at different temperatures

Germination is negatively influenced by water scarcity and by temperatures above or below the optimal range of the species, so it is necessary to know the critical point of absorption for the species or cultivar. The objective of this work was to evaluate the effect of water stress, simulated by solutions of polyethylene glycol 6000 (PEG 6000) at different temperatures, on the germination and vigor of seeds of four cultivars (Branca, Orelha de Vó, Rosinha and Roxinha) of beans (Phaseolus lunatus L.). The water stress simulation was performed using PEG 6000 solutions at concentrations of 0.0, -0.2, -0.4, -0.6, -0.8, -1.0, and -1.2 MPa at temperatures of 25, 30, and 35 ° C. The analyzed variables were percentage of germination at first count, germination speed index, length of aerial part and primary root of seedlings, and dry mass of the respective parts of the seedlings. The seeds of the cultivar Orelha de Vó were more sensitive to water stress, with 88% germinating up to the potential of -0.6 MPa at the tested temperatures. The cultivars Branca, Rosinha, and Roxinha germinated (94, 100, and 100%, respectively) up to the potential of -0.8 MPa. Water stress simulated by PEG (6000) negatively affects seed twinning and seed vigor of bean cultivars.

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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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Water Stress Affect Germination, Seed Vigor and Seedlings Growth of Bidens subalternans

Journal of Agricultural Science ◽

10.5539/jas.v10n9p326 ◽

2018 ◽

Vol 10 (9) ◽

pp. 326

Author(s):

Erivanessa C. Sousa ◽

Janete R. Matias ◽

Juliana P. Pamplona ◽

Sara M. C. Carvalho ◽

Helida C. Mesquita ◽

...

Keyword(s):

Water Stress ◽

Dry Mass ◽

Seed Vigor ◽

Peg 6000 ◽

Germination Process ◽

Germination Speed ◽

Randomized Experimental Design ◽

Osmotic Agent ◽

Osmotic Agents ◽

Adequate Management

The beggartick (Bidens subalternans L.) is one of the main weeds present in agricultural crops, capable of adapting to different environmental conditions. The water stress caused by water deficiency can affect the germination of weed seeds and, consequently, their capacity to colonize the agroecosystem. Knowledge of germination under water stress can be important to obtain an adequate management of the species in the agricultural systems. The objective of this study was to determine the effects of water stress on the germination process and vigor of two batches of Bidens subalternans seeds under different osmotic agents. It was completely randomized experimental design was used, with four replicates of 25 seeds. The treatments were arranged in factorial 6 × 2, with the first factor corresponding six levels of osmotic potentials (0.0, -0.2, -0.4, -0.6, -0.8 and -1.0 MPa) and the second the batches (Pernambuco and Ceará). For the simulation of the water stress, the test of germination was installed in substrate paper blotting, moistened with solutions of polyethylene glycol (PEG 6000) and mannitol. The analyzed variables were germination, germination speed index, length and seedling dry mass. Water stress reduced germination, seed vigor and growth of seedlings in all batches of B. subalternans. Seeds of B. subalternans presented greater tolerance to stress induced by mannitol than to PEG-6000 in terms of germination and germination speed index. Regardless of the osmotic agent used for stress induction, B. subalternans seeds did not tolerate water stress higher than -0.4 MPa.

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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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Assessment of Seed Vigor Tests for Crambe abyssinica

Journal of Agricultural Science ◽

10.5539/jas.v10n12p527 ◽

2018 ◽

Vol 10 (12) ◽

pp. 527

Author(s):

Tássia Fernanda Santos Neri Soares ◽

Bruno Antônio Lemos de Freitas ◽

José Geraldo de Araújo Ferreira Filho ◽

Denise Cunha Fernandes dos Santos Dias ◽

Camila Andrade Fialho ◽

...

Keyword(s):

Electrical Conductivity ◽

Water Stress ◽

Stress Test ◽

Primary Root ◽

Cold Test ◽

Seed Vigor ◽

Stress Tests ◽

Germination Test ◽

Crambe Abyssinica ◽

Seedling Length

Vigor tests are important mainly to identify differences associated to lots performance in field conditions. The objective of this study was to define the most appropriate tests to evaluate the crambe (Crambe abyssinica) seeds vigor. Seven seed lots of crambe were subjected to the standard germination (on the first and last count), germination speed index (GSI), primary root protrusion speed index (PRPSI), seedling length dry and weight seedling, water stress test using PEG 6000 at -0.2 MPa, electrical conductivity and cold test without soil. Crambe lots studied had germination percentages varying from 54 to 80.5%. The GSI, on the first count of water stress and electrical conductivity test ranked lots between two vigor classes The PRPSI, seedling length, seedling dry weight and last count of water stress tests were less sensitive to evaluate vigor for crambe seed. The cold test without soil and the first count of standard germination test were capable to dishtinguish lots more efficiently than the standard germination test on last count by ranking four of the seven seed lots studied.

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Germination of melon seeds under water and thermal stress

Journal of Seed Science ◽

10.1590/2317-1545v39n4188530 ◽

2017 ◽

Vol 39 (4) ◽

pp. 440-447 ◽

Cited By ~ 2

Author(s):

Daniel Teixeira Pinheiro ◽

Denise Cunha Fernandes dos Santos Dias ◽

Joyce de Oliveira Araújo

Keyword(s):

Thermal Stress ◽

Water Stress ◽

Seedling Emergence ◽

Accelerated Aging ◽

Cold Test ◽

Dry Mass ◽

Stress Conditions ◽

Peg 6000 ◽

And Performance ◽

Melon Seeds

Abstract: Seeds vigor can influence seed performance under stress conditions. The objectives of this study were to evaluate the effect of water and thermal stress on germination and performance of melon seedlings, and to verify if germination under stress conditions is an efficient parameter to evaluate the vigor of these seeds. Four lots of ‘Golden Mine’ melon had their initial quality characterized by germination, first count, accelerated aging and seedling emergence tests. Germination under water stress was performed on a paper moistened with PEG 6000 solution at 0.06, -0.3, -0.6 and -0.9 MPa. The percentage and speed of germination, length and dry mass of the seedlings were evaluated. For the thermal stress experiment, cold test and germination at sub- (15 ºC) and supra-optimal (35 ºC) temperatures were performed, as well as at the ideal temperature (25 ºC). The germination of melon seeds under water stress induced by PEG 6000 at -0.3 and -0.6 MPa is an efficient method to detect differences in the physiological potential of lots of melon seeds, but these differences disappear under severe water stress (-0.9 MPa). Germination under sub-optimal temperatures also allows to identify differences in seeds performance and to classify them according to the vigor level.

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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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Osmoprotection in Salvia hispanica L. seeds under water stress attenuators

Brazilian Journal of Biology ◽

10.1590/1519-6984.233547 ◽

2022 ◽

Vol 82 ◽

Author(s):

A. A. Costa ◽

E. P. Paiva ◽

S. B. Torres ◽

M. L. Souza Neta ◽

K. T. O. Pereira ◽

...

Keyword(s):

Salicylic Acid ◽

Water Stress ◽

Gibberellic Acid ◽

Water Deficit ◽

Abiotic Factors ◽

Soluble Sugars ◽

Primary Root ◽

Dry Mass ◽

Control Treatment ◽

Salvia Hispanica

Abstract Salvia hispanica cultivation is recent in Brazil and occurs in the off-season, when there is lower water availability in the soil. Water deficit is one of the abiotic factors that most limit germination for compromising the sequence of metabolic events that culminate with seedling emergence. Several attenuating substances have been used to mitigate the effects resulting from this stress and give higher tolerance to the species. Thus, the objective of this study was to evaluate the action of different agents as water stress attenuators in the germination and accumulation of organic compounds in S. hispanica seedlings. The treatments consisted of pre-soaking the seeds for 4 hours in salicylic acid (1 mM.L-1), gibberellic acid (0.4 mM.L-1), distilled water and control treatment (without soaking). The seeds were germinated at osmotic potentials of 0.0, -0.1, -0.2, -0.3 and -0.4 MPa, using PEG 6000 as an osmotic agent. The variables germination percentage, germination speed index, shoot and primary root lengths, total dry mass, proline, total soluble sugars and total free amino acids were analyzed. Salicylic acid and gibberellic acid led to the best results among the attenuators tested, increasing germination, length, dry mass and biochemical components of S. hispanica seedlings under water deficit. Therefore, salicylic and gibberellic acids are efficient in mitigating water stress in S. hispanica seeds up to the potential of -0.4 MPa.

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SEED GERMINATION OF Pouteria torta (MART.) RADLK. SUBESP. torta IN DIFFERENT ENVIRONMENTAL CONDITIONS

FLORESTA ◽

10.5380/rf.v50i1.59051 ◽

2019 ◽

Vol 50 (1) ◽

pp. 923

Author(s):

Ademir Kleber Morbeck Oliveira ◽

Jose Carlos Pina

Keyword(s):

Seed Germination ◽

Native Species ◽

Primary Root ◽

Seed Vigor ◽

Limited Information ◽

Germination Time ◽

Randomized Design ◽

Germination Speed ◽

Different Temperatures ◽

Mean Germination Time

Germination is considered a critical step in the seedling production process aiming the recovery of environments. Thus, understanding the germination behavior of native species with potential for economic use contributes to the development of the forest seed and seedling chain. Considering the limited information on the tree species Pouteria torta subesp. torta, this study aimed to evaluate its seed germination and formation of normal seedlings using different temperatures and substrates. The experiment was conducted in germination chamber in a research laboratory using two substrates (paper and vermiculite) and six temperatures (20, 25, 30, 35, 20-30 and 25-35 °C) in a completely randomized design in a 2x6 factorial arrangement. Daily evaluation was conducted to verify primary root emission, seed vigor, and seedling formation. The results indicated that the primary root protrusion process began after 20 days of testing under the best conditions, with germination time lasting longer than two months. The results obtained also showed that there was interaction between factors, with use of the vermiculite substrate and the temperatures of 35 and 25-35 °C producing the best germination rates and germination speed index, and use of the paper substrate and the temperatures of 30 and 35 °C showing the best mean germination time. Considering the analyzed variables (germination, germination speed index, and formation of normal seedlings), the temperatures of 35 and 25-35 °C and the vermiculite substrate are the most suitable for the production of Pouteria torta subesp. torta seedlings.

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Accumulation of polyethylene glycol 6000 and its effects on water content and carbohydrate level in water-stressed tomato plants

Canadian Journal of Botany ◽

10.1139/b88-140 ◽

1988 ◽

Vol 66 (5) ◽

pp. 970-973 ◽

Cited By ~ 20

Author(s):

E. Jacomini ◽

A. Bertani ◽

S. Mapelli

Keyword(s):

Polyethylene Glycol ◽

Water Stress ◽

Soluble Sugar ◽

Physiological Effects ◽

Tomato Plants ◽

Peg 6000 ◽

Plant Parts ◽

Tomato Roots ◽

Peg Treatment ◽

Polyethylene Glycol 6000

Young tomato plants were grown in 10 or 25% polyethylene glycol (PEG) 6000 solutions to impose water stress. Plant organs were analyzed to ascertain whether the various plant parts accumulated PEG and to determine the physiological effects. PEG 6000 was taken up by tomato roots and translocated to the shoots. PEG accumulation was greater in roots and in the first leaves and negligible in apical leaves. In all leaves there was an increase in soluble-sugar concentration during the PEG treatment. However, PEG-accumulating leaves showed a delay in dehydration in comparison with leaves where PEG was not accumulated. To explain this behaviour we hypothesize that PEG was accumulated in extracellular spaces and that, as a consequence, water was drawn out from the cells, inducing cellular but not tissue dehydration.

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