Chapter 5: The germination test

ABSTRACT Nine fungal strains isolated from an aged and heavily contaminated soil were identified and screened to assess their degradative potential. Among them, Allescheriella sp. strain DABAC 1, Stachybotrys sp. strain DABAC 3, and Phlebia sp. strain DABAC 9 were selected for remediation trials on the basis of Poly R-478 decolorization associated with lignin-modifying enzyme (LME) production. These autochthonous fungi were tested for the abilities to grow under nonsterile conditions and to degrade various aromatic hydrocarbons in the same contaminated soil. After 30 days, fungal colonization was clearly visible and was confirmed by ergosterol determination. In spite of subalkaline pH conditions and the presence of heavy metals, the autochthonous fungi produced laccase and Mn and lignin peroxidases. No LME activities were detected in control microcosms. All of the isolates led to a marked removal of naphthalene, dichloroaniline isomers, o-hydroxybiphenyl, and 1,1′-binaphthalene. Stachybotrys sp. strain DABAC 3 was the most effective isolate due to its ability to partially deplete the predominant contaminants 9,10-anthracenedione and 7H-benz[DE]anthracen-7-one. A release of chloride ions was observed in soil treated with either Allescheriella sp. strain DABAC 1 or Stachybotrys sp. strain DABAC 3, suggesting the occurrence of oxidative dehalogenation. The autochthonous fungi led to a significant decrease in soil toxicity, as assessed by both the Lepidium sativum L. germination test and the Collembola mortality test.

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Multiplicação, teste de germinação e resistência a sitophilus zeamais de variedades de milho crioulo cultivado no cone sul de Rondônia/ Multiplication, germination test and resistance to sitophilus zeamais of cultivated cropled core varieties in the south cone of Rondonia

Brazilian Applied Science Review ◽

10.34115/basrv3n6-010 ◽

2019 ◽

Vol 3 (6) ◽

pp. 2412-2428

Author(s):

Wagner dos Santos Machado ◽

Aline Fonseca do Nascimento ◽

Hebert da Cruz Damasceno ◽

Joice dos Santos Pinheiro ◽

Layanne Muniz Sprey

Keyword(s):

Zea Mays ◽

Sitophilus Zeamais ◽

The South ◽

Germination Test ◽

Para Determinar

O milho (Zea mays) é um produto agrícola cultivado em todo território nacional e com inúmeras utilizações. Com o surgimento da agricultura moderna, as sementes crioulas foram, em geral, substituídas por cultivares híbridos, com elevado potencial produtivo, porém mais dependentes de insumos e tecnologias intensivas. Pode ser armazenado por longos períodos, porém, devido seu armazenamento sem inspeção inicial do local, pode propiciar o ataque de pragas, dentre elas, destaca-se o gorgulho Sitophilus zeamais que danifica o grão acarretando grandes prejuízos para os agricultores e tornando o impróprio para o consumo. Uma boa fonte de genótipos resistentes são as variedades crioulas, ou seja, aquelas tradicionalmente cultivadas pelos pequenos agricultores e que ainda não foram modificadas, seja pela biotecnologia ou por outros processos de melhoramento. O teste de germinação é realizado para determinar o percentual germinativo das sementes de milho, teste esse baseado no procedimento oficial da RAS para avaliar a capacidade das sementes desenvolverem plântulas normais em condições ideais. Sendo assim, o objetivo desse trabalho foi mostrar, através de seu material genético o potencial de 10 variedades multiplicadas em relação ao cultivar convencional SSH 7990 PRO2, assim avaliando seu poder germinativo e sua resistência ao ataque do Gorgulho (Sitophilus zeamais). Para ambos os testes o delineamento experimental utilizado foi o inteiramente casualizado. No método de confinamento ou sem chance de escolha foram utilizadas 4 repetições com 10 gramas da variedade crioula mais a testemunha, contendo em cada recipiente 30 gorgulhos não sexados. Finalizando a avaliação com teste de germinação, utilizou-se 5 repetições de 50 sementes em rolo de papel germitest, totalizando 250 sementes, onde a variedade de Milho colorido obteve um maior percentual de germinação, com média de 99,6 %. Considerando a evidência desses materiais crioulos serem mais resistentes ao ataque da praga, pode-se concluir que de fato, esses materiais são mais tolerantes comparadas a cultivar híbrida, assim as variedades Pipoca preta, Dente de cavalo e Jabotão vermelho se mostraram menos atraentes ao gorgulho, e a cultivar convencional SSH 7990 PRO2 se mostrou mais atraente, tendo uma perda média de peso de 0,3538 gramas durante os 15 dias confinados.

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Physiological potential of soybean seeds after maturation and submitted to artificial drying

Journal of Seed Science ◽

10.1590/2317-1545v39n4175656 ◽

2017 ◽

Vol 39 (4) ◽

pp. 374-384

Author(s):

Cesar Pedro Hartmann Filho ◽

André Luís Duarte Goneli ◽

Tathiana Elisa Masetto ◽

Elton Aparecido Siqueira Martins ◽

Guilherme Cardoso Oba

Keyword(s):

Moisture Content ◽

Dry Matter ◽

Seedling Emergence ◽

Accelerated Aging ◽

Maturation Stage ◽

Soybean Seeds ◽

Germination Test ◽

Moisture Contents ◽

Three Samples ◽

Maturation Stages

Abstract: This study evaluated the physiological potential of soybean seeds harvested during two seasons, on different maturation stages and subjected to different drying temperatures. The seeds were harvested at the maturations stages R7, R7 + 2, R7 + 3, R7 + 5, R7 + 6, R7 + 7, R7 + 10 and R7 + 12 days (55, 50, 45, 40, 35, 30, 25, and 20% of moisture content). For each maturation stage, seeds were divided into three samples: one sample was used to directly evaluate the physiological potential, and the others were dried at 40 °C and 50 °C, until reaching the moisture content of 11.5%. The physiological potential was evaluated through germination test, first germination count of germination, accelerated aging, modified cold, electrical conductivity and seedling emergence. The maximum physiological potential of seeds is achieved at the moisture content of 55%, the point that the dry matter is maximum. The seeds became tolerant to artificial drying approximately at the stage R7 + 7 days (30% of moisture content). Germination and vigor of the soybean seeds reduce as the drying temperature is increased from 40 °C to 50 °C, and this effect is enhanced when the seeds show moisture contents above 30%.

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PHYSIOLOGICAL POTENTIAL AND CONSERVATION OF MURUCI (Byrsonima crassifolia) SEEDS

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452017475 ◽

2017 ◽

Vol 39 (5) ◽

Author(s):

CAMILA RIBEIRO DE SOUZA GRZYBOWSKI ◽

WALNICE MARIA OLIVEIRA DO NASCIMENTO ◽

ROSEMEIRE CARVALHO DA SILVA ◽

ELISA SERRA NEGRA VIEIRA ◽

MARISTELA PANOBIANCO

Keyword(s):

Block Design ◽

Rapid Assessment ◽

Germplasm Collection ◽

Germination Test ◽

Byrsonima Crassifolia ◽

Randomized Block Design ◽

Relative Air Humidity ◽

Different Temperatures ◽

Mother Plants ◽

Tetrazolium Test

ABSTRACT The goal of the present study is to assess the physiological potential of Byrsonima crassifoliaseeds and analyze the procedures of the germination and tetrazolium tests, as well as the conservation of such seeds by testing different combinations of packaging and environment. The experiment used pyrenes of the clone Açu, collected from mother plants in the germplasm collection of muruci plants of Embrapa Amazonia Oriental, in Belém, Brazil. Different temperatures were tested in the germination test (25, 30, 35 and 20 - 30 ºC). The best methodology and assessment dates were determined for the test, and the seedlings of the species were characterized. Viability was assessed with the tetrazolium test, with combinations of hydration methods (by immersion and between paper towels), staining periods (3 and 4 h) and concentrations of tetrazolium solution (0.5, 0.7 and 1.0%). Storage of muruci pyrenes was evaluated at three, six and twelve months, in polyethylene and Kraft paper bags, under dry chamber and refrigerator conditions. The study used a randomized block design with four replicates. The data underwent analysis of variance. In conclusion, the physiological potential of seeds of B. crassifoliacan be assessed by the germination test conducted in sand, with alternating temperatures of 20-30 ºC, or with the use of the tetrazolium test (with staining for three hours in the tetrazolium solution at 1.0%) as a rapid assessment of viability. Muruci pyrenes can be kept in polythene or paper Kraft bags for up to 12 months, in a dry chamber at 16 ºC and with relative air humidity of 50 to 60%.

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Adjustment of the methodology of the tetrazolium test for estimating viability of Eugenia uniflora L. seeds during storage

Journal of Seed Science ◽

10.1590/2317-1545v36n31022 ◽

2014 ◽

Vol 36 (3) ◽

pp. 344-351 ◽

Cited By ~ 5

Author(s):

Daiana Karoline Kaiser ◽

Laura Cristiane Nascimento de Freitas ◽

Rubia Priscila Biron ◽

Simone Cristina Simonato ◽

Michele Fernanda Bortolini

Keyword(s):

Seed Viability ◽

Germination Test ◽

Preparation Methods ◽

Eugenia Uniflora ◽

Paper Towel ◽

Plastic Bags ◽

Longitudinal Cutting ◽

Direct Immersion ◽

Tetrazolium Test

The study aimed to adjust the methodology of the tetrazolium test to estimate seed viability of Eugenia uniflora L. (Surinam Cherry). Seeds were collected in September 2012 and divided into four lots: freshly harvested (Lot I); stored in plastic bags in a refrigerator at 10 °C for: 15 days (Lot II); 30 days (Lot III); and 45 days (Lot IV). The freshly harvested seeds were preconditioned with direct immersion in water and wet paper towel, followed or not by longitudinal cutting. The seeds were immersed in a 0.1% tetrazolium solution for 4 hours at 30 °C. Appropriate soaking and preparation methods were applied to the seeds lots using three tetrazolium concentrations: 0.1; 0.5; and 1.0%; and four preconditioning periods (2, 4, 6 and 8 hours) at 30 °C. The viability results obtained by the tetrazolium test were compared with those of the germination test. Direct immersion of seeds in water for 24 hours at 25 °C, followed by a longitudinal cut was efficient for preconditioning the seeds. Seed staining with tetrazolium solution at a concentration of 0.5% for 2 hours at 30 °C can be used to estimate the viability of freshly harvested and stored Surinam Cherry seeds.

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Foliar application of silicon and the effect on wheat seed yield and quality

Journal of Seed Science ◽

10.1590/s2317-15372013000100012 ◽

2013 ◽

Vol 35 (1) ◽

pp. 86-91 ◽

Cited By ~ 7

Author(s):

Samantha Rigo Segalin ◽

Caroline Huth ◽

Thais D'Avila Rosa ◽

Diógenes Barella Pahins ◽

Liliane Marcia Mertz ◽

...

Keyword(s):

Seed Yield ◽

Foliar Application ◽

Accelerated Aging ◽

Dry Weight ◽

Wheat Cultivars ◽

Wheat Seed ◽

Germination Test ◽

Yield And Quality ◽

Physiological Quality

Adequate nutrients for plants are important for increasing the yield and quality of the seeds produced. The objective of this study was to evaluate foliar fertilization with silicon in wheat and its effect on seed yield and physiological quality. Treatments consisted of two silicon dosages (three and six liters silicon per hectare) and the control (no silicon) and five wheat cultivars: OR "Quartzo", OR "Ônix", Fundacep "Linhagem", Fundacep "Campo Real" and Fundacep "Horizonte". The experimental design was randomized blocks with four replications. After physiological maturity, harvesting and threshing of the seeds were done manually. Seed samples were evaluated for yield and physiological quality from the germination test, first germination count, seedling dry weight, accelerated aging, electrical conductivity, 1000 seeds and hectoliter weights. The results showed that the foliar application of silicon at the dosages tested did not affect the yield and physiological quality of the seeds produced by the wheat cultivars.

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Seed germination and antioxidant enzyme activity in seedlings of diploid and tetraploid bahiagrass under water restriction

Ciência Rural ◽

10.1590/0103-8478cr20190382 ◽

2020 ◽

Vol 50 (5) ◽

Author(s):

Gabriel Streck Bortolin ◽

Alfredo José Salinas-Arcienega ◽

Yutcelia Carolina Galviz-Fajardo ◽

Luciano do Amarante ◽

Carlos Eduardo da Silva Pedroso ◽

...

Keyword(s):

Seed Germination ◽

Physiological Responses ◽

Dry Mass ◽

Germination Percentage ◽

Early Growth ◽

Paspalum Notatum ◽

Water Restriction ◽

Germination Test ◽

Growth Activity ◽

Higher Temperature

ABSTRACT: The objective of the following research was to investigate the physiological responses of two bahiagrass genotypes (Paspalum notatum Flügge) submitted to water restriction, induced by polyethylene glycol (PEG6000), during seed germination. Seeds of cv. Pensacola (diploid) and Bagual ecotype (tetraploid) were placed on paper moistened with osmotic solutions at potentials of 0.0; -0.1; -0.2 and -0.3 MPa. Composed of two subsamples of 100 seeds and four experimental units per treatment, the germination test was conducted in a germination chamber under alternating temperatures of 30 °C (8 hours) and 20 °C (16 hours), with presence of light during the higher temperature. Final germination percentage and germination speed index of the seeds, as well as early growth, activity and expression of antioxidant enzymes of seedlings were evaluated. The water restriction induced by PEG6000 reduced the percentage of germination in Pensacola (from 74% to 59%) and Bagual (34% to 10%). For the latter, the evaluation of seedlings showed higher dry mass in relation to cv. Pensacola (1.7 times higher in root and 1.6 times in shoot). In response to moderate water restriction, the genotypes showed increases in root growth (1.7 times higher in -0.1 compared to 0.0 MPa), both in expression and enzymatic activity (superoxide dismutase and catalase).

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Nitrogen doses and splitting in top dressing in the production, quality, and macronutrients content in zucchini (Cucurbita pepo) seeds

Research Society and Development ◽

10.33448/rsd-v10i10.18708 ◽

2021 ◽

Vol 10 (10) ◽

pp. e328101018708

Author(s):

Ana Emília Barbosa Tavares ◽

Natália de Brito Lima Lanna ◽

Lidiane Fernandes Colombari ◽

Emanuele Possas de Souza ◽

Bruno Novaes Menezes Martins ◽

...

Keyword(s):

Chemical Composition ◽

Seed Weight ◽

Cucurbita Pepo ◽

Production Quality ◽

N Fertilization ◽

Germination Test ◽

Macronutrient Content ◽

Yield Quality ◽

The Relationship

Despite the importance of the nutrients, mainly nitrogen, in the formation and chemical composition of the seeds, little research has been done to verify the relationship between the nutrients supplied to the plants and the quality of the seeds produced. The objective of this study was to evaluate the influence of nitrogen doses and splitting on yield, quality and macronutrients content in zucchini seeds. Two experiments (crop 2014 and crop 2015) were installed, with thirteen treatments in the factorial scheme 4x3+1, with four nitrogen doses in top dressing (62.5; 125.0; 187.5; 250.0 kg ha-1), three splitting (1/6+1/3+1/2; 1/4+1/2+1/4; 1/3+1/3+1/3 of total dose in each split), and one treatment without N fertilization in top dressing (dose 0), with four replications. Seed production and quality and macronutrient content in seeds were evaluated. There wasn’t significant effect on number of fruits and seeds produced per plant. However, in crop 2014 the higher the doses of N in top dressing, the higher the seed weight per fruit and per plant, the weight of 100 seeds and the vigor (first count in germination test). In crop 2015, seeds with the best quality (germination and first counting) were obtained in the 1/4+1/2+1/4 splitting. The decreasing order of the macronutrient content in the seeds was N>P>K>Mg>S>Ca.

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ELECTRICAL CONDUCTIVITY AND QUALITY OF DIFFERENT UMBEL ORDER CARROT SEEDS

Revista Brasileira de Agropecuária Sustentável ◽

10.21206/rbas.v9i04.8079 ◽

2020 ◽

Vol 9 (04) ◽

pp. 75-81

Author(s):

Luana de Souza Marinke ◽

Hugo César Rodrigues Moreira Catão ◽

Gabrielly Fernanda Francisco ◽

Ítala Menegon Castilho ◽

Letícia Rodrigues de Oliveira ◽

...

Keyword(s):

Electrical Conductivity ◽

Germination Rate ◽

Statistical Design ◽

Germination Test ◽

Aerial Portion ◽

Initial Characterization ◽

Different Temperatures ◽

Physiological Quality ◽

Final Score

Carrot seeds exhibit irregular vigor due to the wide blooming period of the crop. Results from germination tests are insufficient to evaluate the physiological potential. Thus, vigor tests are used in combination with germination tests. The objective of this work was to evaluate the quality of carrot seeds from different umbel order and the electrical conductivity under different temperatures and imbibing periods. Carrot seeds from cultivar Brasilia were used to perform the experiments. Content of water, the first and the final score of the germination test, index of germination rate, and length of roots and of the aerial portion were determined in the initial characterization. The electrical conductivity test was completed with replicates containing 50 seeds, in 25 mL deionized water at 20, 25 and 30oC. Evaluations were performed with 2, 4, 6, 8, 12 and 24 hours of imbibing period. The experiment was accomplished under a completely random statistical design. The quality of carrot seeds varied according to the umbel order. Seeds of secondary umbels showed better physiological quality. The electrical conductivity test is efficient to evaluate the vigor of carrot seeds with 8 hours of imbibing period at 25°C.

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Identification of geneticaly modified soybean seeds resistant to glyphosate

Scientia Agricola ◽

10.1590/s0103-90162004000300017 ◽

2004 ◽

Vol 61 (3) ◽

pp. 336-341 ◽

Cited By ~ 11

Author(s):

Maria Ângela André Tillmann ◽

Shirlie West

Keyword(s):

Genetically Modified ◽

Soybean Seeds ◽

Germination Test ◽

Hypocotyl Length ◽

Genetically Modified Soybean ◽

Paper Towel ◽

Soybean Genotypes ◽

Physiological Quality ◽

Resistance Trait ◽

Moist Paper Towel

Advances in genetic engineering permit the modification of plants to be tolerant to certain herbicides that are usually not selective. For practical and commercial purposes, it is important to be able to detect the presence or absence of these traits in genotypes. The objective of this research was to develop a procedure for identifying genetically modified soybean (Glycine max L. Merr.) with resistance to the herbicide glyphosate. Two studies were conducted based on germination test. In the first study, soybean seeds were pre-imbibed in paper towel with the herbicide solutions, then transferred to moist paper towel for the germination test. In the second study, seeds were placed directly in herbicide solutions in plastic cups and tested for germination using the paper towel method. Eight soybean genotypes were compared: four Roundup Ready, that contained the gene resistant to the herbicide (G99-G725, Prichard RR, G99-G6682, and H7242 RR) and four non-transgenic parental cultivars (Boggs, Haskell, Benning, and Prichard). In the first study, the seeds were imbibed for 16 hours at 25°C in herbicide concentrations between 0.0 and 1.5% of the glyphosate active ingredient. In the second, seeds were subjected to concentrations between 0.0 and 0.48%, for one hour, at 30°C. The evaluation parameters were: germination, hypocotyl length, root length and total length of the seedlings. Both methods are efficient in identifying glyphosate-resistant soybean genotypes. It is possible to identify the genetically modified soybean genotypes after three days, by imbibing the seed in 0.12% herbicide solution, and after six days if the substrate is pre-imbibed in a 0.6% herbicide solution. The resistance trait was identified in all cultivars, independent of the initial physiological quality of the seed.

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