Understanding Seed Dormancy and Germination

Seeds are highly important part of living things, without which life would not exist. All of our daily necessities are totally dependent on seed and seed stock, like food and fruits, so also is many of the natural resources that we use as consumers such as, timber, cotton, paper, essential\edible oils, all which started their live as seeds. Basically, a seed consists of a tiny underdeveloped plant, the embryo, which is enclosed by a covering called the seed coat. Germination of seed occurs when the embryo grows into a functioning plant. It involves the rejuvenation of the metabolic pathways that lead to growth and the emergence of the radicle (root) and plumule (shoot). For germination to occur, three basic factors must exist, the seed must be viable, dormancy must be controlled and the proper environmental conditions for germination must be available. Dormancy simply means the inability of seeds to germinate even when the necessary environmental conditions (temperature, humidity, oxygen, and light) are favorable for germination. Dormancy is a principal factor restricting the production of crops. Several physical and chemical pretreatments can be applied to the organic material (seeds) to control dormancy. This review discusses the conditions necessary for germination and the fundamental factors necessary for breaking dormancy.

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A comparative study of seed dormancy and germination in an annual and a perennial species of Senna (Fabaceae)

Seed Science Research ◽

10.1017/s0960258500004475 ◽

1998 ◽

Vol 8 (4) ◽

pp. 501-512 ◽

Cited By ~ 43

Author(s):

Jerry M. Baskin ◽

Xiaoying Nan ◽

Carol C. Baskin

Keyword(s):

Seed Dormancy ◽

Seed Coat ◽

Seasonal Temperature ◽

Hard Seed ◽

Breaking Dormancy ◽

Wide Range ◽

Natural Temperature ◽

Colour Morphs ◽

Hard Seed Coat ◽

Seed Dormancy And Germination

AbstractSeed dormancy and germination ofSenna marilandicaandS. obtusifoliawere compared in greenhouse and laboratory studies. About 90% of theS. obtusifoliaseeds were green and had hard seed coat dormancy, whereas the other 10% were brown and nondormant. Seed-colour morphs did not occur inS. marilandica, and nearly 100% of the seeds had hard seed coat dormancy. Seeds ofS. obtusifoliawere significantly heavier than those ofS. marilandica. Mechanical scarification was very effective in overcoming dormancy in seeds of both species. However, concentrated sulfuric acid, absolute ethanol and boiling water were less effective in breaking dormancy in seeds ofS. marilandicathan in those ofS. obtusifolia. Further, incubating seeds at 30/15 to 40/25°C and dry-heat treatments at 80–100°C were ineffective in breaking dormancy inS. marilandica, but significantly increased germination percentages inS. obtusifolia. In neither species were simulated daily/seasonal temperature shifts effective in breaking dormancy. Scarified seeds of both species germinated over a wide range of temperatures in both light and darkness. Under near-natural temperature conditions, seeds ofS. marilandicagerminated in spring only, whereas those ofS. obtusifoliaemerged in late spring and throughout summer. Both species can form a long-lived seed bank. Dormancy break by high field temperatures in seeds ofS. obtusifoliaallows this species to germinate throughout the warm growing season and thus contributes to its success as a weed in arable crops.

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Physical, physiological and anatomical changes in Erythrina speciosa Andrews seeds from different seasons related to the dormancy degree

Journal of Seed Science ◽

10.1590/2317-1545v40n3199428 ◽

2018 ◽

Vol 40 (3) ◽

pp. 331-341 ◽

Cited By ~ 4

Author(s):

Debora Manzano Molizane ◽

Pricila Greyse dos Santos Julio ◽

Sandra Maria Carmello-Guerreiro ◽

Claudio José Barbedo

Keyword(s):

Seed Coat ◽

Environmental Conditions ◽

Climatic Conditions ◽

Mother Plant ◽

Anatomical Changes ◽

Breaking Dormancy ◽

Different Seasons ◽

Impermeable Layer ◽

Harvest Year ◽

Mature Seeds

Abstract: Dormancy, a process that allows seeds to survive in adverse environments, needs to be broken for germination to start, for example, by the disruption of the impermeable layer of seeds. Mature seeds of Erythrina speciosa present seed coat impermeability, whose degree depends on the year of production. The objective of this study was to analyze the physical, physiological, anatomical, and ultrastructural seed coat modifications, according to the environmental conditions in which seeds were produced, as well as the seed sensitivity to treatments as for breaking dormancy. E. speciosa seeds were collected for six years in a row and were analyzed as for dormancy degree. Moreover, chemical scarifications by different immersion times were applied on seeds from two production years, as well as mechanical scarification, which was an efficient methodology to overcome dormancy. Different immersion times by acid scarification were necessary to break dormancy in each harvest year. It was possible to conclude that the climatic conditions under which the mother plant is submitted can influence the dormancy degree of E. speciosa seeds, but the expected anatomical changes between dormant and non-dormant seeds were not found in seeds from this species.

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Some Biophysical and Biochemical Properties of Edible Oils Exposed To Environmental Conditions

The International Conference on Chemical and Environmental Engineering ◽

10.21608/iccee.2016.35049 ◽

2016 ◽

Vol 8 (13) ◽

pp. 212-227

Author(s):

Kotb A ◽

Siam E ◽

Shams El-Din S ◽

Khedr Y ◽

El-Kholy A

Keyword(s):

Environmental Conditions ◽

Edible Oils ◽

Biochemical Properties

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Regulation of Seed Dormancy and Germination Mechanisms in a Changing Environment

International Journal of Molecular Sciences ◽

10.3390/ijms22031357 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1357

Author(s):

Ewelina A. Klupczyńska ◽

Tomasz A. Pawłowski

Keyword(s):

Climate Change ◽

Seed Germination ◽

Seed Dormancy ◽

Environmental Conditions ◽

Global Climate ◽

Plant Evolution ◽

Suitable Habitat ◽

Climate Change Scenarios ◽

Adaptation Mechanism ◽

Seed Dormancy And Germination

Environmental conditions are the basis of plant reproduction and are the critical factors controlling seed dormancy and germination. Global climate change is currently affecting environmental conditions and changing the reproduction of plants from seeds. Disturbances in germination will cause disturbances in the diversity of plant communities. Models developed for climate change scenarios show that some species will face a significant decrease in suitable habitat area. Dormancy is an adaptive mechanism that affects the probability of survival of a species. The ability of seeds of many plant species to survive until dormancy recedes and meet the requirements for germination is an adaptive strategy that can act as a buffer against the negative effects of environmental heterogeneity. The influence of temperature and humidity on seed dormancy status underlines the need to understand how changing environmental conditions will affect seed germination patterns. Knowledge of these processes is important for understanding plant evolution and adaptation to changes in the habitat. The network of genes controlling seed dormancy under the influence of environmental conditions is not fully characterized. Integrating research techniques from different disciplines of biology could aid understanding of the mechanisms of the processes controlling seed germination. Transcriptomics, proteomics, epigenetics, and other fields provide researchers with new opportunities to understand the many processes of plant life. This paper focuses on presenting the adaptation mechanism of seed dormancy and germination to the various environments, with emphasis on their prospective roles in adaptation to the changing climate.

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Biocompatible Material from Indonesian Natural Resource of Wild Silkmoth Cocoon

Advances in Tropical Biodiversity and Environmental Sciences ◽

10.24843/atbes.2017.v01.i02.p05 ◽

2018 ◽

Vol 1 (2) ◽

pp. 47

Author(s):

Tjokorda Gde Tirta Nindhia ◽

Zdenek Knejzlík ◽

Tomáš Ruml ◽

I Wayan Surata ◽

Tjokorda Sari Nindhia

Keyword(s):

Mechanical Properties ◽

Natural Resource ◽

Chemical Properties ◽

Hot Water ◽

Physical And Chemical Properties ◽

Living Things ◽

Biocompatibility Testing ◽

Good Biocompatibility ◽

Physical And Chemical ◽

And Chemical Properties

Silk can be produced by spider or insect and have prospect as biomaterial for regenerative healing in medical treatment. Silk having physical and chemical properties that support biocompatibility in the living things..In this research, silk that was obtained from Indonesia natural resource of Attacus atlas silkmoth was explored and then will be developed for biocompatible biomaterial. The treatment with NaOH was developed to separate the fiber from the cocoon. The obtained fiber is investigated its mechanical property by performing tensile test for single fiber. The biocompatibility testing was conducted with human cell (osteosarccoma) cultivation. The result identify that separation by using NaOH yield better better mechanical properties comparing konvenstional method with boiling in hot water. Biocompatibility testing indicate that the the fiber having good biocompatibility.

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Differential strengths of molecular determinants guide environment specific mutational fates

10.1101/134569 ◽

2017 ◽

Cited By ~ 1

Author(s):

Rohan Dandage ◽

Rajesh Pandey ◽

Gopal Jayaraj ◽

Kausik Chakraborty

Keyword(s):

Protein Folding ◽

Molecular Evolution ◽

Protein Stability ◽

Environmental Effects ◽

Environmental Conditions ◽

Fitness Landscape ◽

Dependent Manner ◽

The Common ◽

Physical And Chemical ◽

Substrate Binding Protein

AbstractUnder the influence of selection pressures imposed by natural environments, organisms maintain competitive fitness through underlying molecular evolution of individual genes across the genome. For molecular evolution, how multiple interdependent molecular constraints play a role in determination of fitness under different environmental conditions is largely unknown. Here, using Deep Mutational Scanning (DMS), we quantitated empirical fitness of ∼2000 single site mutants of Gentamicin-resistant gene (GmR). This enabled a systematic investigation of effects of different physical and chemical environments on the fitness landscape of the gene. Molecular constraints of the fitness landscapes seem to bear differential strengths in an environment dependent manner. Among them, conformity of the identified directionalities of the environmental selection pressures with known effects of the environments on protein folding proves that along with substrate binding, protein stability is the common strong constraint of the fitness landscape. Our study thus provides mechanistic insights into the molecular constraints that allow accessibility of mutational fates in environment dependent manner.Author SummaryEnvironmental conditions play a central role in both organismal adaptations and underlying molecular evolution. Understanding of environmental effects on evolution of genotype is still lacking a depth of mechanistic insights needed to assist much needed ability to forecast mutational fates. Here, we address this issue by culminating high throughput mutational scanning using deep sequencing. This approach allowed comprehensive mechanistic investigation of environmental effects on molecular evolution. We monitored effects of various physical and chemical environments onto single site mutants of model antibiotic resistant gene. Alongside, to get mechanistic understanding, we identified multiple molecular constraints which contribute to various degrees in determining the resulting survivabilities of mutants. Across all tested environments, we find that along with substrate binding, protein stability stands out as the common strong constraints. Remarkable direct dependence of the environmental fitness effects on the type of environmental alteration of protein folding further proves that protein stability is the major constraint of the gene. So, our findings reveal that under the influence of environmental conditions, mutational fates are channeled by various degrees of strengths of underlying molecular constraints.

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Avaliação de Tratamentos de Superação de Dormência em Sementes do Delonix regia (Boger ex Hook.) Raf coletadas no Horto Florestal Tote Garcia, Cuiabá, Mato Grosso

Ensaios e Ciência C Biológicas Agrárias e da Saúde ◽

10.17921/1415-6938.2017v21n1p48-51 ◽

2017 ◽

Vol 21 (1) ◽

pp. 48

Author(s):

Ana Carolina Amorim Marques ◽

Osvaldo Borges Pinto Junior ◽

Vera Lucia Lopes Vieira

Keyword(s):

Ambient Temperature ◽

Thermal Shock ◽

Environmental Conditions ◽

Economic Value ◽

Mato Grosso ◽

Delonix Regia ◽

Breaking Dormancy ◽

Manual Counting ◽

The Family ◽

Temperature Water

A árvore Delonix regia (flamboyant) pertence à família Fabaceae, subfamília Caesalpinioideae, originário da ilha de Madagascar. Tem potencial valor econômico ornamental, pois se trata de uma espécie extremamente florífera e exuberante, indicada para programas de arborização, como parques, praças e jardins, sendo inadequada para ruas e avenidas, devido a suas raízes serem caracterizadas como superficiais. Essa espécie exótica, adaptada as condições ambientais de clima tropical, tem porte de 10 – 12m de altura, de tronco volumoso, espesso, com raízes tabulares. Por apresentar características de dormência tegumentar, este trabalho teve objetivo de avaliar alguns tratamentos para superação de dormência das sementes do Delonix regia. O experimento foi do tipo quantitativo, em que as sementes foram submetidas a três tratamentos e uma testemunha, em um total de 4 tratamentos, com 75 sementes cada. A emergência foi observada in locu, por meio de contagem manual. Os tratamentos utilizados foram: escarificação mecânica com lixa (n° 120); imersão em água em temperatura ambiente por 72 horas, choque térmico com imersão das sementes em água a 80 ºC por 05 min e a testemunha em que não houve nenhuma intervenção. Observou-se que a escarificação mecânica e o choque térmico proporcionaram os melhores resultados para superação de dormência das sementes do Delonix regia.Palavras-chave: Paisagismo. Dormência. Emergência.AbstractThe tree Delonix regia (flamboyant) belongs to the family Fabaceae, subfamily Caesalpinioideae, originally from the island of Madagascar. It has the potential ornamental economic value, because it is an extremely floriferous and exuberant species suitable for reforestations programs such as parks,and gardens, being inappropriate for streets and avenues, because its roots are characterized as superficial. This exotic species, adapted to the environmental conditions of tropical climate, reaches size of 10-12 m tall, large trunk, dense with tabular roots. It is renowned for being an extremely floriferous and exuberant species. By presenting cutaneous numbness characteristics, the objective of this study was to evaluate some treatments to overcome dormancy of seeds Delonix regia. The experiment was the quantitative type, in which the seeds were subjectedto three treatments and a control, a total of 4 treatments with 75 seeds each. The emergence was observed in locus through manual counting. The treatments were mechanical scarification with sandpaper (#120); immersion in ambient temperature water for 72 hours, thermal shock deep soaking the seeds in water at 80 °C for 5 minutes and the control, which had no intervention. It was observed that the mechanical scarification and thermal shock provided the best results for breaking dormancy of seeds Delonix regia.Keywords: Landscaping. Emergency Seedling. Dormancy

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Peat decomposition – shaping factors, significance in environmental studies and methods of determination; a literature review

Geologos ◽

10.1515/logos-2016-0005 ◽

2016 ◽

Vol 22 (1) ◽

pp. 61-69 ◽

Cited By ~ 11

Author(s):

Danuta Drzymulska

Keyword(s):

Chemical Composition ◽

Literature Review ◽

Ground Water ◽

Environmental Conditions ◽

Meteoric Water ◽

Climatic Conditions ◽

Review Of Literature ◽

Forming Process ◽

Physical And Chemical

Abstract A review of literature data on the degree of peat decomposition – an important parameter that yields data on environmental conditions during the peat-forming process, i.e., humidity of the mire surface, is presented. A decrease in the rate of peat decomposition indicates a rise of the ground water table. In the case of bogs, which receive exclusively atmospheric (meteoric) water, data on changes in the wetness of past mire surfaces could even be treated as data on past climates. Different factors shaping the process of peat decomposition are also discussed, such as humidity of the substratum and climatic conditions, as well as the chemical composition of peat-forming plants. Methods for the determination of the degree of peat decomposition are also outlined, maintaining the division into field and laboratory analyses. Among the latter are methods based on physical and chemical features of peat and microscopic methods. Comparisons of results obtained by different methods can occasionally be difficult, which may be ascribed to different experience of researchers or the chemically undefined nature of many analyses of humification.

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