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1

Effect of surface sterilization, fumigation and gamma irradiation on the microflora and germination of barley seeds.  

PubMed

Sodium hypochlorite (NaOCl) and mercuric chloride (HgCl2) surface sterilization, methyl bromide and propylene oxide fumigation and gamma irradiation treatments were compared for their effectiveness in killing microorganisms on or within barley seeds. Surface sterilization with 12.5, 25 or 50% (v/v) NaOCl for 5, 15 or 30 min, decreased Fusarium spp., Epicoccum purpurascens, and Bacillus spp. but did not kill Alternaria alternata. However, surface sterilization with 0.1 or 0.2% (w/v) HgCl2 for 3 min significantly decreased A. alternata, Fusarium spp. and E. purpurascens but Bacillus spp. were only killed by 0.3% (w/v) HgCl2 used for 10 min, which also decreased seed germination. Aspergillus flavus inoculated onto barley seeds as spores, was completely killed by surface sterilization with NaOCl but not with HgCl2, while Fusarium culmorum was killed by both NaOCl and HgCl2 treatments. Fumigation with methyl bromide yielding a concentration-time product of 3000 mg h l-1 or with propylene oxide giving a concentration-time product of 2400 mg h l-1 eliminated all filamentous fungi but Bacillus spp. and yeasts survived, and both treatments adversely affected seed germination. Gamma irradiation at a dose of 4 kGy eliminated most Alternaria, Fusarium and Epicoccum spp. but a dose of 12 kGy was required to kill Bacillus spp., yeasts and Aureobasidium pullulans. Germination was improved slightly up to a dose of 8 kGy but gradually decreased with increase in dosage to 15 kGy of gamma irradiation. PMID:1863528

Ramakrishna, N; Lacey, J; Smith, J E

1991-05-01

2

CONSERVED AND DIVERGENT TRANSCRIPTIONAL REGULATION OF SEED GERMINATION, AND THE REGULATORY ROLES OF GIBBERELLIN AND ABSCISIC ACID IN BARLEY GERMINATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed germination and early seedling growth is a complex biological process requiring closely coordinated expression of numerous genes and pathways. Gibberellin and abscisic acid play central roles in regulating seed germination. To gain insight into the global transcriptional control of seed germina...

3

Watermelon Seed Germination  

E-print Network

Watermelon Seed Germination Purdue University Cooperative Extension Service BP-62 Seed Germination of the necessary genetic material or chromosomes. These seed, known as triploid, have special germination requirements. This bulletin addresses triploid watermelon seed germination and transplant production. First

4

Conserved transcriptional regulatory programs underlying rice and barley germination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed germination is accompanied with concerted transcriptional expression of many genes and biological pathways. Barley and rice germinations have been divergent from each other for 50-60 million years. However, there is little knowledge about the conservation and divergence in transcriptional regul...

5

Evidence for Osmotic Regulation of Hydrolytic Enzyme Production in Germinating Barley Seeds  

Microsoft Academic Search

a-Amylase levels inintact seeds ofbarley (Hordeum vulgare L.cv.Himalaya) reachamaximumat3to4daysofgermina- tionwhilegibberellin levels continue toincrease beyond 6days ofgermination. Incontrast toitseffect onhalfseeds, gibberel- licaciddoesnotincrease thetotal amountofa-amylase pro- ducedingerminating seeds. Theinability ofgibberellic acid tostimulate a-amylase production isnotrelated toitsavail- ability; rather, evidence suggests thata factor (s)inwhole seedsprevents further enhancement ofa-amylase formation andaccumulation. Hydrolysis products accumulate inthesub- aleurone spaceoftheendosperm ofgerminating seedsup to concentrations of570milliosmolar. Chromatography ofthese

R. L. JONESAND; J. E. Armstrong

1971-01-01

6

Evidence for a Slow-Turnover Form of the Ca2+-Independent Phosphoenolpyruvate Carboxylase Kinase in the Aleurone-Endosperm Tissue of Germinating Barley Seeds1  

PubMed Central

Phosphoenolpyruvate carboxylase (PEPC) activity was detected in aleurone-endosperm extracts of barley (Hordeum vulgare) seeds during germination, and specific anti-sorghum (Sorghum bicolor) C4 PEPC polyclonal antibodies immunodecorated constitutive 103-kD and inducible 108-kD PEPC polypeptides in western analysis. The 103- and 108-kD polypeptides were radiolabeled in situ after imbibition for up to 1.5 d in 32P-labeled inorganic phosphate. In vitro phosphorylation by a Ca2+-independent PEPC protein kinase (PK) in crude extracts enhanced the enzyme's velocity and decreased its sensitivity to l-malate at suboptimal pH and [PEP]. Isolated aleurone cell protoplasts contained both phosphorylated PEPC and a Ca2+-independent PEPC-PK that was partially purified by affinity chromatography on blue dextran-agarose. This PK activity was present in dry seeds, and PEPC phosphorylation in situ during imbibition was not affected by the cytosolic protein-synthesis inhibitor cycloheximide, by weak acids, or by various pharmacological reagents that had proven to be effective blockers of the light signal transduction chain and PEPC phosphorylation in C4 mesophyll protoplasts. These collective data support the hypothesis that this Ca2+-independent PEPC-PK was formed during maturation of barley seeds and that its presumed underlying signaling elements were no longer operative during germination. PMID:9952447

Osuna, Lidia; Pierre, Jean-Nöel; González, María-Cruz; Alvarez, Rosario; Cejudo, Francisco J.; Echevarría, Cristina; Vidal, Jean

1999-01-01

7

ALPHA-GLUCOSIDASES FROM THE GLYCOSIDE HYDROLASE FAMILY 31 IN GERMINATING SEEDS AND SEEDLING LEAVES OF BARLEY  

Technology Transfer Automated Retrieval System (TEKTRAN)

Of the four starch degrading enzymes in plants, only alpha-amylase and alpha-glucosidase have been extensively studied. Both alpha-amylase and alpha-glucosidase are important in germinating seeds in direct initiation of attack on starch grains. Five different alpha-glucosidases have been found in ...

8

Seed germination and vigor.  

PubMed

Germination vigor is driven by the ability of the plant embryo, embedded within the seed, to resume its metabolic activity in a coordinated and sequential manner. Studies using "-omics" approaches support the finding that a main contributor of seed germination success is the quality of the messenger RNAs stored during embryo maturation on the mother plant. In addition, proteostasis and DNA integrity play a major role in the germination phenotype. Because of its pivotal role in cell metabolism and its close relationships with hormone signaling pathways regulating seed germination, the sulfur amino acid metabolism pathway represents a key biochemical determinant of the commitment of the seed to initiate its development toward germination. This review highlights that germination vigor depends on multiple biochemical and molecular variables. Their characterization is expected to deliver new markers of seed quality that can be used in breeding programs and/or in biotechnological approaches to improve crop yields. PMID:22136565

Rajjou, Loïc; Duval, Manuel; Gallardo, Karine; Catusse, Julie; Bally, Julia; Job, Claudette; Job, Dominique

2012-01-01

9

Easy PEAsy Seed Germination  

NSDL National Science Digital Library

In this activity, learners determine the necessary conditions for pea seed germination. This activity encourages learners to make predictions and think about how they might investigate the effects of variables like light, temperature, and moisture.

2012-04-09

10

Seed dormancy and germination  

Microsoft Academic Search

Seed dormancy and germination are complex adaptive traits of higher plants that are influenced by a large number of genes and environmental factors. Studies of genetics and physiology have shown the important roles of the plant hormones abscisic acid and gibberellin in the regulation of dormancy and germination. More recently, the use of quantitative genetics and mutant approaches has allowed

Maarten Koornneef; Leónie Bentsink; Henk Hilhorst

2002-01-01

11

Compositional and digestibility changes in sprouted barley and canola seeds  

Microsoft Academic Search

Barley and canola seeds were sprouted over a 5 day period, in laboratory conditions under room temperature (22°C) and room lighting. Following initial hydration, seeds were kept moist by wetting the germination trays at 9 a.m., 1 p.m. and 6 p.m. daily. A parallel germination experiment using 200 g quantities of seeds in petri dishes was conducted. Starting from the

T. Y. Chung; E. N. Nwokolo; J. S. Sim

1989-01-01

12

Cactus seed germination: a review  

Microsoft Academic Search

The present review tries to give a general overview of the available information on cactus seed germination. First, information about the family Cactaceae is discussed, concerning aspects such as distribution and general characteristics. Seed distinctive features are mentioned, such as colour, form, and size. Aspects of seed physiology, such as germination and dormancy, as well as seed dynamics including dispersal,

Mariana Rojas-Aréchiga; Carlos Vázquez-Yanes

2000-01-01

13

The effects of salinity and osmotic stress on barley germination rate: sodium as an osmotic regulator  

PubMed Central

Background and Aims Seed germination is negatively affected by salinity, which is thought to be due to both osmotic and ion-toxicity effects. We hypothesize that salt is absorbed by seeds, allowing them to generate additional osmotic potential, and to germinate in conditions under which they would otherwise not be able to germinate. Methods Seeds of barley, Hordeum vulgare, were germinated in the presence of either pure water or one of five iso-osmotic solutions of polyethylene-glycol (PEG) or NaCl at 5, 12, 20 or 27 °C. Germination time courses were recorded and germination indices were calculated. Dry mass, water content and sodium concentration of germinating and non-germinating seeds in the NaCl treatments at 12 °C were measured. Fifty supplemental seeds were used to evaluate the changes in seed properties with time. Key Results Seeds incubated in saline conditions were able to germinate at lower osmotic potentials than those incubated in iso-osmotic PEG solutions and generally germinated faster. A positive correlation existed between external salinity and seed salt content in the saline-incubated seeds. Water content and sodium concentration increased with time for seeds incubated in NaCl. At higher temperatures, germination percentage and dry mass decreased whereas germination index and sodium concentration increased. Conclusions The results suggest that barley seeds can take up sodium, allowing them to generate additional osmotic potential, absorb more water and germinate more rapidly in environments of lower water potential. This may have ecological implications, allowing halophytic species and varieties to out-compete glycophytes in saline soils. PMID:20929898

Zhang, Hongxiang; Irving, Louis J.; McGill, Craig; Matthew, Cory; Zhou, Daowei; Kemp, Peter

2010-01-01

14

Characterization of the Entire Cystatin Gene Family in Barley and Their Target Cathepsin L-Like Cysteine-Proteases, Partners in the Hordein Mobilization during Seed Germination1[W  

PubMed Central

Plant cystatins are inhibitors of cysteine-proteases of the papain C1A and legumain C13 families. Cystatin data from multiple plant species have suggested that these inhibitors act as defense proteins against pests and pathogens and as regulators of protein turnover. In this study, we characterize the entire cystatin gene family from barley (Hordeum vulgare), which contain 13 nonredundant genes, and identify and characterize their target enzymes, the barley cathepsin L-like proteases. Cystatins and proteases were expressed and purified from Escherichia coli cultures. Each cystatin was found to have different inhibitory capability against barley cysteine-proteases in in vitro inhibitory assays using specific substrates. Real-time reverse transcription-polymerase chain reaction revealed that inhibitors and enzymes present a wide variation in their messenger RNA expression patterns. Their transcripts were mainly detected in developing and germinating seeds, and some of them were also expressed in leaves and roots. Subcellular localization of cystatins and cathepsin L-like proteases fused to green fluorescent protein demonstrated the presence of both protein families throughout the endoplasmic reticulum and the Golgi complex. Proteases and cystatins not only colocalized but also interacted in vivo in the plant cell, as revealed by bimolecular fluorescence complementation. The functional relationship between cystatins and cathepsin L-like proteases was inferred from their common implication as counterparts of mobilization of storage proteins upon barley seed germination. The opposite pattern of transcription expression in gibberellin-treated aleurones presented by inhibitors and enzymes allowed proteases to specifically degrade B, C, and D hordeins stored in the endosperm of barley seeds. PMID:19759340

Martinez, Manuel; Cambra, Ines; Carrillo, Laura; Diaz-Mendoza, Mercedes; Diaz, Isabel

2009-01-01

15

Purification and partial characterization of a 31-kDa cysteine endopeptidase from germinated barley  

Microsoft Academic Search

Proteolytic enzymes hydrolyze cereal seed storage proteins into small peptides and amino acids, which are very important for seed germination and the malting process. A cysteine-class endopeptidase was purified from 4-d-germinated barley (Hordeum vulgare L. cv. Morex). Four purification steps were used, carboxymethyl cellulose cation-exchange chromatography, chromatofocusing, size-exclusion chromatography, and electroelution from a polyacrylamide gel. The endopeptidase was most active

Ningyan Zhang; Berne I. Jones

1996-01-01

16

Conserved Transcriptional Regulatory Programs Underlying Rice and Barley Germination  

PubMed Central

Germination is a biological process important to plant development and agricultural production. Barley and rice diverged 50 million years ago, but share a similar germination process. To gain insight into the conservation of their underlying gene regulatory programs, we compared transcriptomes of barley and rice at start, middle and end points of germination, and revealed that germination regulated barley and rice genes (BRs) diverged significantly in expression patterns and/or protein sequences. However, BRs with higher protein sequence similarity tended to have more conserved expression patterns. We identified and characterized 316 sets of conserved barley and rice genes (cBRs) with high similarity in both protein sequences and expression patterns, and provided a comprehensive depiction of the transcriptional regulatory program conserved in barley and rice germination at gene, pathway and systems levels. The cBRs encoded proteins involved in a variety of biological pathways and had a wide range of expression patterns. The cBRs encoding key regulatory components in signaling pathways often had diverse expression patterns. Early germination up-regulation of cell wall metabolic pathway and peroxidases, and late germination up-regulation of chromatin structure and remodeling pathways were conserved in both barley and rice. Protein sequence and expression pattern of a gene change quickly if it is not subjected to a functional constraint. Preserving germination-regulated expression patterns and protein sequences of those cBRs for 50 million years strongly suggests that the cBRs are functionally significant and equivalent in germination, and contribute to the ancient characteristics of germination preserved in barley and rice. The functional significance and equivalence of the cBR genes predicted here can serve as a foundation to further characterize their biological functions and facilitate bridging rice and barley germination research with greater confidence. PMID:24558366

Lin, Li; Tian, Shulan; Kaeppler, Shawn; Liu, Zongrang; An, Yong-Qiang (Charles)

2014-01-01

17

Proteomic insights into seed germination in response to environmental factors.  

PubMed

Seed germination is a critical process in the life cycle of higher plants. During germination, the imbibed mature seed is highly sensitive to different environmental factors.However, knowledge about the molecular and physiological mechanisms underlying the environmental effects on germination has been lacking. Recent proteomic work has provided invaluable insight into the molecular processes in germinating seeds of Arabidopsis, rice (Oryza sativa), soybean (Glycine max), barley (Hordeum vulgare), maize (Zeamays), tea (Camellia sinensis), European beech (Fagus sylvatica), and Norway maple (Acer platanoides) under different treatments including metal ions (e.g. copper and cadmium), drought, low temperature, hormones, and chemicals (gibberellic acid, abscisic acid, salicylic acid, and ?-amanitin), as well as Fusarium graminearum infection. A total of 561 environmental factor-responsive proteins have been identified with various expression patterns in germinating seeds. The data highlight diverse regulatory and metabolic mechanisms upon seed germination, including induction of environmental factor-responsive signaling pathways, seed storage reserve mobilization and utilization, enhancement of DNA repair and modification, regulation of gene expression and protein synthesis, modulation of cell structure, and cell defense. In this review, we summarize the interesting findings and discuss the relevance and significance for our understanding of environmental regulation of seed germination. PMID:23986916

Tan, Longyan; Chen, Sixue; Wang, Tai; Dai, Shaojun

2013-06-01

18

Compounds That Promote Seed Germination  

NSDL National Science Digital Library

The two molecules for this month come from the section Compound in Smoke Provides the Spark for Germination in the article about "Research Advances" by Angela G. King. These molecules have been demonstrated to stimulate seed germination under various conditions. The butenolide moiety is frequently encountered in natural products. An interesting approach to the synthesis of such molecules can be found in this Organic Letters article (accessed January 2005).

19

Seed Development and Germination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed is the fertilized and matured ovule of angiosperms and gymnosperms and represents a crucial stage in the life cycle of plants. Seeds of diverse plant species may display differences in size, shape and color. Despite apparent morphological variations, most mature seeds consist of three major com...

20

Thermoperiodism in Cocklebur Seed Germination  

PubMed Central

Germination potential in nondormant, upper cocklebur (Xanthium pensylvanicum Wallr.) seeds, which were incapable of germinating under constant temperatures below 25 C in air, was increased by exposure to diurnally alternating temperatures. The cocklebur seeds failed to respond to the temperature fluctuations in the beginning of water imbibition, and their responsiveness appeared only after aerobic presoaking for a limited period or after anaerobic pretreatment for 1 to 3 days. Maximal germination was obtained after exposure to a thermoperiodic regime of 8 hours at 23 C and 16 hours at 8 C. A process occurring during the high temperature phase was aerobic and had to precede the inductive low temperature phase, its effect increasing with temperature. Critical minimum length of the inductive low temperature phase changed with the duration of a preceding anaerobiosis, for instance about 4 hours after 1 day anaerobiosis, but about 2 hours after 2 days. Percentage of subsequent germination was in proportion to the number of thermoperiodic cycles. A process of the inductive low temperature phase was not perturbed by inserting a brief higher temperature period into its phase; indeed, such insertion rather increased germination potential when performed in the earlier parts of the inductive low temperature phase. The effect of the low temperature survived for 13 to 17 hours during the higher temperature period. PMID:16660310

Esashi, Yohji; Tsukada, Yoshiya

1978-01-01

21

7 CFR 201.54 - Number of seeds for germination.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Number of seeds for germination. 201.54 Section... § 201.54 Number of seeds for germination. At least 400 seeds...be added to the regular germination tolerances. The seeds shall be tested in...

2011-01-01

22

7 CFR 201.54 - Number of seeds for germination.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Number of seeds for germination. 201.54 Section... § 201.54 Number of seeds for germination. At least 400 seeds...be added to the regular germination tolerances. The seeds shall be tested in...

2012-01-01

23

7 CFR 201.54 - Number of seeds for germination.  

...2014-01-01 false Number of seeds for germination. 201.54 Section... § 201.54 Number of seeds for germination. At least 400 seeds...be added to the regular germination tolerances. The seeds shall be tested in...

2014-01-01

24

7 CFR 201.54 - Number of seeds for germination.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Number of seeds for germination. 201.54 Section... § 201.54 Number of seeds for germination. At least 400 seeds...be added to the regular germination tolerances. The seeds shall be tested in...

2013-01-01

25

Barley  

Technology Transfer Automated Retrieval System (TEKTRAN)

The U.S. malting and brewing industries are America’s largest consumers of barley, purchasing more than one-half of the U.S. barley grain crop. More than 70% of the hectares seeded to barley are seeded to cultivars recommended by the American Malting Barley Association (AMBA). The malting and brewi...

26

Respiratory Transition during Seed Germination 1  

PubMed Central

Experiments with germinating seeds of Wayne soybean (Glycine max Merr.) show that between the 4th and the 8th hour of germination, respiration experiences a transition from predominantly “alternate” respiration, which is sensitive to salicylhydroxamic acid, to a cyanide-sensitive respiration. The dependence of early germination stages on alternate respiration is reflected in several types of seed functions, including subsequent root growth rate, chlorophyll synthesis, and germination itself. The early period of germination is shown to require a normal O2 tension, which is no longer a requirement at later stages. The changing sensitivity to cyanide and to salicylhydroxamic acid is found to be common to seven different types of germinating seeds. It is proposed that the alternate pathway of respiration provides something essential for the completion of the earliest stages of seed germination. PMID:16659465

Yentur, Semahat; Leopold, A. Carl

1976-01-01

27

Protocol to Sterilize & Charcoal-Germinate Maize Seeds 1 PROTOCOL TO STERILIZE AND CHARCHOAL-GERMINATE MAIZE SEEDS  

E-print Network

Protocol to Sterilize & Charcoal-Germinate Maize Seeds 1 PROTOCOL TO STERILIZE AND CHARCHOAL-GERMINATE MAIZE SEEDS (Last revised August 2010) This protocol is used for germinating moldy seeds that would

Wurtele, Eve Syrkin

28

Seed germination characteristics of Halogeton glomeratus  

Microsoft Academic Search

Halogeton glomeratus (Bieb.) C.A. Mey, an annual forb in the family Chenopodiaceae, is widely distributed in the inland salt deserts of western North America. Experiments were conducted to determine the effects of NaCl and temperature on seed germination and the recovery of germination responses after transfer to distilled water. Seeds of H. glomeratus were germinated at various temperature regimes (5-15°C,

M. Ajmal Khan; Bilquees Gul; Darrell J. Weber

2001-01-01

29

Differential LongSAGE tag abundance analysis in a barley seed germination time course and validation with relative real-time RT-PCR  

Microsoft Academic Search

A Long Serial Analysis of Gene Expression (LongSAGE) approach was employed to identify changes in mRNA transcript abundance in a time course of malting barley (Hordeum vulgare L.). Statistical analyses confidently identified 57 LongSAGE sequence tags as having significant changes in abundance between points in the time course. Eight of the genes which correspond to these tags were targeted for

Jessica F White; Toni Pacey-Miller; Peter C Bundock; Robert J Henry

2008-01-01

30

Phytochrome and Seed Germination. I. Temperature Dependence and Relative PFR Levels in the Germination of Dark-germinating Tomato Seeds  

PubMed Central

Germination of the dark-germinating seeds of 3 varieties of tomato is controlled by the phytochrome system. Germination is inhibited by far red radiation and repromoted by red applied after far red. At low temperatures, 17 to 20°, a single, low energy far red irradiation is sufficient to inhibit germination in all 3 varieties. At higher temperatures far red is less effective in the inhibition of the germination of the tomato seeds. The phytochrome fraction present as PFR in the dark-germinating seeds of the Ace variety is about 40% of the total phytochrome present. PMID:16656511

Mancinelli, Alberto L.; Yaniv, Zohara; Smith, Phyllis

1967-01-01

31

Seed Germination in Chenopodium album L  

PubMed Central

Effects of ethylene, gibberellins, and kinetin on the germination of two lots of Chenopodium album L. seeds, collected from the field in 1982 and 1983, were studied in relation to the availability of nitrate. The experiments were conducted in darkness and at temperatures ranging from 12 to 32°C. Ethylene induced over 75% germination in the 1983 seed but had little effect on the 1982 seed. Nitrate was only slightly promotive in either of the two seed lots. A combination of ethylene and nitrate, however, acted synergistically on 1982 seed, resulting in as much germination as that induced in 1983 seed by ethylene alone. In 1983 seed, a combination of ethylene and nitrate was only marginally more effective than ethylene. A similar relationship was observed in the effects of gibberellic acid4+7 (GA4+7) and nitrate on seeds from the two lots. The 1982 seed, which responded synergistically to combinations of nitrate with ethylene or GA4+7 was found to contain an extremely low endogenous level of nitrate as compared to 1983 seed. Thus, high levels of either endogenous or applied nitrate appeared to enhance the germination response to ethylene or GA4+7. Kinetin had no effect on 1982 seed and only a small promotive effect on 1983 seed. There was no synergism between kinetin and nitrate in either of the seed lots. PMID:16664167

Saini, Hargurdeep S.; Bassi, Pawan K.; Spencer, Mary S.

1985-01-01

32

The oxygen requirement of germinating flax seeds  

NASA Astrophysics Data System (ADS)

Experiments for earth orbit are typically prepared on the ground and often germinated in orbit in order to study gravity effects on developing seedlings. Germination requires the breakdown of storage compounds and respiration. In orbit the formation of a water layer around the seed may further limit oxygen availability. Therefore, the oxygen content of the available gas volume is one of the limiting factors for seed germination. In preparation for an upcoming shuttle experiment (MICRO on STS-107) we studied germination and growth of flax (Linum usitatissimum L.) seedlings in the developed hardware. We tested per seed chamber (gas volume = 14 mL, O2 = 2.9 mL) between 4 to 32 seeds glued to germination paper by 1% (w/v) gum guar. A lexan cover and a gasket hermetically sealed each of the eight chambers. For imbibition of the seeds a previously optimized amount of distilled water was dispensed through sealed inlets. The seedlings were allowed to grow for either 32 to 48 h on a clinostat or without microgravity simulation. Then their root length was measured. With 32 seeds per chamber, four times the intended number of seeds for the flight, the germination rate decreased from 94 to 69%, and the root length was reduced by 20%. Experiments on the germination and root length in controlled atmospheres (5, 10, 15 and 21% O2 ) suggest that germination and growth for two days requires about 200 :l of O (1 mL air) per seed. Our2 experiments correlate oxygen dependency from seed mass and germination temperature, and analyze accumulation of gaseous metabolites (supported by NASA grant NAG10-0190).

Kuznetsov, O.; Hasenstein, K.

33

Search for endophytic diazotrophs in barley seeds.  

PubMed

Eight endophytic isolates assigned to Pseudomonas, Azospirillum, and Bacillus genera according to pheno-genotypic features were retrieved from barley seeds under selective pressure for nitrogen-fixers. Genetic relationships among related isolates were investigated through RAPD. Six isolates displayed nitrogen-fixing ability, while all could biosynthesize indolacetic acid in vitro and showed no antibiosis effects against Azospirillum brasilense Az39, a recognized PGPR. PMID:25242949

Zawoznik, Myriam S; Vázquez, Susana C; Díaz Herrera, Silvana M; Groppa, María D

2014-01-01

34

Search for endophytic diazotrophs in barley seeds  

PubMed Central

Eight endophytic isolates assigned to Pseudomonas, Azospirillum, and Bacillus genera according to pheno-genotypic features were retrieved from barley seeds under selective pressure for nitrogen-fixers. Genetic relationships among related isolates were investigated through RAPD. Six isolates displayed nitrogen-fixing ability, while all could biosynthesize indolacetic acid in vitro and showed no antibiosis effects against Azospirillum brasilense Az39, a recognized PGPR. PMID:25242949

Zawoznik, Myriam S.; Vázquez, Susana C.; Díaz Herrera, Silvana M.; Groppa, María D.

2014-01-01

35

SEED GERMINATION AND VIABILITY OF WYOMING SAGEBRUSH IN NORTHERN NEVADA  

Microsoft Academic Search

SUMMARY Seed size and germination behavior affect performance of early seedlings. The purpose of this study was to investigate rela- tionships between seed size and germination percentage, germina- tion rate, time course of germination and seed viability in Wyo- ming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle and Young). Working hypotheses were: 1) for single seeds, germination percentages and rates

Carlos A. Busso; Mónica Mazzola; Barry L. Perryman

2005-01-01

36

Effects of seed maturity, seed storage and pre-germination treatments on seed germination of cleome ( Cleome gynandra L.)  

Microsoft Academic Search

The influence of seed maturity, seed storage and germination pre-treatments on seed germination of cleome (Cleome gynandra L.) were investigated. Seed maturation studies showed that capsules harvested at 18 days after anthesis possessed the highest dry weight with 19.2% moisture and 1% germination. Development of fresh-ungerminated seed was observed with increasing maturity of fruit, suggesting that cleome exhibited forms of

Boonsong Ekpong

2009-01-01

37

Freezing tolerance of conifer seeds and germinants.  

PubMed

Survival after freezing was measured for seeds and germinants of four seedlots each of interior spruce (Picea glauca x engelmannii complex), lodgepole pine (Pinus contorta Dougl. ex Loud.), Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) and western red cedar (Thuja plicata Donn ex D. Donn). Effects of eight seed treatments on post-freezing survival of seeds and germinants were tested: dry, imbibed and stratified seed, and seed placed in a growth chamber for 2, 5, 10, 15, 20 or 30 days in a 16-h photoperiod and a 22/17 degrees C thermoperiod. Survival was related to the water content of seeds and germinants, germination rate and seedlot origin. After freezing for 3 h at -196 degrees C, dry seed of most seedlots of interior spruce, Douglas-fir and western red cedar had 84-96% germination, whereas lodgepole pine seedlots had 53-82% germination. Freezing tolerance declined significantly after imbibition in lodgepole pine, Douglas-fir and interior spruce seed (western red cedar was not tested), and mean LT50 of imbibed seed of these species was -30, -24.5 and -20 degrees C, respectively. Freezing tolerance continued to decline to a minimum LT50 of -4 to -7 degrees C after 10 days in a growth chamber for interior spruce, Douglas-fir and lodgepole pine, or after 15 days for western red cedar. Minimum freezing tolerance was reached at the stage of rapid hypocotyl elongation. In all species, a slight increase in freezing tolerance of germinants was observed once cotyledons emerged from the seed coat. The decrease in freezing tolerance during the transition from dry to germinating seed correlated with increases in seed water content. Changes in freezing tolerance between 10 and 30 days in the growth chamber were not correlated with seedling water content. Within a species, seedlots differed significantly in freezing tolerance after 2 or 5 days in the growth chamber. Because all seedlots of interior spruce and lodgepole pine germinated quickly, there was no correlation between seedlot hardiness and rate of germination. Germination rate and freezing tolerance of Douglas-fir and western red cedar seedlots was negatively correlated. There was a significant correlation between LT50 after 10 days in the growth chamber and minimum spring temperature at the location of seedlot origin for interior spruce and three seedlots of western red cedar, but no relationship was apparent for lodgepole pine and Douglas-fir. PMID:14652223

Hawkins, B J; Guest, H J; Kolotelo, D

2003-12-01

38

Effects of Air Temperature on Seed Germination  

NSDL National Science Digital Library

This activity begins as a classroom investigation, but may extend to a field investigation where students will determine the effects of air temperature on seed germination. This is accomplished by developing investigative questions, recording, and analyzing data.

Amy MacArthur

39

Tansley review Seed dormancy and the control of germination  

E-print Network

Tansley review Seed dormancy and the control of germination William E. Finch-Savage1 and Gerhard This section on applied aspects of the control of seed germination by dormancy is an additional part the seed at the molecular level? 5. Applied aspects of the control of germination by seed dormancy Seeds

Leubner, Gerhard

40

7 CFR 201.53 - Source of seeds for germination.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Source of seeds for germination. 201.53 Section 201...Act § 201.53 Source of seeds for germination. (a) When both purity...germination tests are required, seeds for germination shall be taken from the...

2012-01-01

41

7 CFR 201.53 - Source of seeds for germination.  

...2014-01-01 false Source of seeds for germination. 201.53 Section 201...Act § 201.53 Source of seeds for germination. (a) When both purity...germination tests are required, seeds for germination shall be taken from the...

2014-01-01

42

7 CFR 201.53 - Source of seeds for germination.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Source of seeds for germination. 201.53 Section 201...Act § 201.53 Source of seeds for germination. (a) When both purity...germination tests are required, seeds for germination shall be taken from the...

2013-01-01

43

7 CFR 201.53 - Source of seeds for germination.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Source of seeds for germination. 201.53 Section 201...Act § 201.53 Source of seeds for germination. (a) When both purity...germination tests are required, seeds for germination shall be taken from the...

2011-01-01

44

Software Tools for Weed Seed Germination Modeling  

Technology Transfer Automated Retrieval System (TEKTRAN)

The next generation of weed seed germination models will need to account for variable soil microclimate conditions. In order to predict this microclimate environment we have developed a suite of individual tools (models) that can be used in conjunction with the next generation of weed seed germinati...

45

Hormonal and molecular events during seed dormancy release and germination  

E-print Network

Hormonal and molecular events during seed dormancy release and germination Gerhard Leubner on Seeds, Salamanca, Spain, 12-16 May 2002 Symposium Seed Dormancy and Germination #12;Leubner-Metzger (2003) - page 2 Introduction Seed germination of species with 'coat-imposed' dormancy is determined

Leubner, Gerhard

46

Inhibitory effect of myrigalone A on seed germination 1 Myrigalone A inhibits Lepidium sativum seed germination by interference with  

E-print Network

Inhibitory effect of myrigalone A on seed germination 1 Myrigalone A inhibits Lepidium sativum seed herbicide) and different terpenes on the endosperm rupture of germinating Lepidium sativum seeds in the figure) and sulcotrione. (B) Seedlings grown from seeds germinated in the presence of the herbicide

Leubner, Gerhard

47

Promotion of seed germination by cyanide.  

PubMed

Potassium cyanide at 3 mum to 10 mm promotes germination of Amaranthus albus, Lactuca sativa, and Lepidium virginicum seeds. l-Cysteine hydrogen sulfide lyase, which catalyzes the reaction of HCN with l-cysteine to form beta-l cyanoalanine, is active in the seeds. beta-l-Cyanoalanine is the most effective of the 23 alpha-amino acids tested for promoting germination of A. albus seeds. Aspartate, which is produced by enzymatic hydrolysis of asparagine formed by hydrolysis from beta-cyanoalanine, is the second most effective of the 23 amino acids. Uptake of aspartate-4-(14)C is much lower than of cyanide.Radioactive tracer in K(14)CN shows uptake of about 1.5 mumoles of HCN per gram of A. albus and L. sativa seeds after 20 hours of imbibition. Extracts of the seeds gave high (14)C activity in beta-cyanoalanine, asparagine, and aspartate. The acid-hydrolyzed protein extract gave high activity only in aspartate. Tests were negative for free cyanide in the seed. Respiration of the seed is inhibited more than 75% by KCN and by KN(3) at 10 mm. Azide at greater than 1.0 mm inhibits the promotion of germination by cyanides. Neither 0.1 mm KCN nor KN(3) inhibit O(2) consumption, whereas lower concentrations promote germination. It is concluded that the high rate of utilization of cyanide in the reaction to form beta-l-cyanoalanine and the subsequent incorporation into protein limit any inhibition of oxygen consumption. The promotion of seed germination is substrate-limited by asparagine-aspartate, which is required for protein synthesis. PMID:16658492

Taylorson, R B; Hendricks, S B

1973-07-01

48

Promotion of Seed Germination by Cyanide  

PubMed Central

Potassium cyanide at 3 ?m to 10 mm promotes germination of Amaranthus albus, Lactuca sativa, and Lepidium virginicum seeds. l-Cysteine hydrogen sulfide lyase, which catalyzes the reaction of HCN with l-cysteine to form ?-l cyanoalanine, is active in the seeds. ?-l-Cyanoalanine is the most effective of the 23 ?-amino acids tested for promoting germination of A. albus seeds. Aspartate, which is produced by enzymatic hydrolysis of asparagine formed by hydrolysis from ?-cyanoalanine, is the second most effective of the 23 amino acids. Uptake of aspartate-4-14C is much lower than of cyanide. Radioactive tracer in K14CN shows uptake of about 1.5 ?moles of HCN per gram of A. albus and L. sativa seeds after 20 hours of imbibition. Extracts of the seeds gave high 14C activity in ?-cyanoalanine, asparagine, and aspartate. The acid-hydrolyzed protein extract gave high activity only in aspartate. Tests were negative for free cyanide in the seed. Respiration of the seed is inhibited more than 75% by KCN and by KN3 at 10 mm. Azide at greater than 1.0 mm inhibits the promotion of germination by cyanides. Neither 0.1 mm KCN nor KN3 inhibit O2 consumption, whereas lower concentrations promote germination. It is concluded that the high rate of utilization of cyanide in the reaction to form ?-l-cyanoalanine and the subsequent incorporation into protein limit any inhibition of oxygen consumption. The promotion of seed germination is substrate-limited by asparagine-aspartate, which is required for protein synthesis. PMID:16658492

Taylorson, R. B.; Hendricks, S. B.

1973-01-01

49

Germination of yaupon (Ilex vomitoria Ait.) seed  

E-print Network

as the maior food reserve in holly seeds and the stimulation of growth by dextrose (Ives, 1923), suggested the possible use of a lipase system for the breakdown of lipids to hasten germination. A new plant growth regulator, 2-chloroehanepho. phoic acid..., or castor bean lipase extract. All treatments were placed in a germinator maintained at 15. 5 C for the duration of the treatments. Specific treat-, ants were: l. Ethrel: Excised seed. were soaked for 8 hours in an aqueous solution of' 1, 0CO and 5, 000...

Fleming, Carl Michael

1970-01-01

50

Seed biology and in vitro seed germination of Cypripedium.  

PubMed

Cypripedium orchids have high horticultural value. The populations of most species are very geographically restricted and they are becoming increasingly rare due to the destruction of native habitats and illegal collection. Reduction of the commercial value through large-scale propagation in vitro is a preferable option to reduce pressure from illegal collection. Cypripedium species are commercially propagated via seed germination in vitro. This review focuses on in vitro seed germination and provides an in-depth analysis of the seed biology of this genus. PMID:24191720

Zeng, Songjun; Zhang, Yu; Teixeira da Silva, Jaime A; Wu, Kunlin; Zhang, Jianxia; Duan, Jun

2014-12-01

51

Improved germination of the seeds of whistling pine (Casuarina equisetifolia)  

E-print Network

Agronomy Improved germination of the seeds of whistling pine (Casuarina equisetifolia) Forst, and application of 0.1 mM IAA solution. Incubating soaked seeds in continuous red light caused the germination blue light, green light and in the dark. Germination was completely prevented in seeds pretreated

Paris-Sud XI, Université de

52

Original article The influence of seed age on germinative response  

E-print Network

Original article The influence of seed age on germinative response to the effects of fire in Pinus was to understand the germinative response to fire of three species of seeds of different ages. An experi- ment / P. radiata / E. globulus / germination / fire / seed age Résumé. ­ Influence de l'âge de la semence

Paris-Sud XI, Université de

53

Seed germination ecology in southwestern Western Australia  

Microsoft Academic Search

Germination responses of species from the native plant communities of southwestern Western Australia can be related to syndromes\\u000a of life history, fire response, and seed storage, and also to factors related to environmental stress. The Mediterranean-type\\u000a climate of the region with periodic drought and recurrent fires affects the production of viable seeds in plants of limited\\u000a stature and rooting depth.

David T. Bell; Julie A. Plummer; Susan K. Taylor

1993-01-01

54

Change of seed germination rate with storage time of Santalum album L. (Indian sandalwood) seeds  

E-print Network

Change of seed germination rate with storage time of Santalum album L. (Indian sandalwood) seeds Y of accommodating 100 seeds per bed. Cleaned river sand was used as the germination media that was filled.5 cm. In order to avoid the common fungal attacks on sandalwood seeds, the seeds and the germination

55

Radish (Raphanus sativus) seed size affects germination response to coumarin  

Technology Transfer Automated Retrieval System (TEKTRAN)

The inhibition of seed germination by an allelochemical is generally greater in small seeds than in large seeds. Studies reporting these results used a large number of plant species that varied in seed size, which might have introduced differences in germination characteristics or various parameter...

56

Effects of Fertilisers on Seed Germination in New Zealand  

Microsoft Academic Search

This paper uses data from a series of local field and glasshouse studies to highlight the main issues associated with fertilisers causing germination damage to seed. When fertiliser was placed in close contact with seed either through a conventional drill or when placed on top of seed in the glasshouse, in general small seed was more predisposed to germination damage

M. D. Craighead

57

Abstract I present the results of a 2-year experiment comparing seed predation, seed germination, and seed-  

E-print Network

Abstract I present the results of a 2-year experiment comparing seed predation, seed germination are probably due to lower levels of seed germination. Forest fragments have higher air and soil temperatures into plant conservation efforts. Keywords Habitat fragmentation · Heliconiaceae · Seed germination · Seed

Bruna, Emilio M.

58

Interaction of light and hormone signals in germinating seeds  

Microsoft Academic Search

Seed germination is regulated by several environmental factors, such as moisture, oxygen, temperature, light, and nutrients.\\u000a Light is a critical regulator of seed germination in small-seeded plants, including Arabidopsis and lettuce. Phytochromes,\\u000a a class of photoreceptors, play a major role in perceiving light to induce seed germination. Classical physiological studies\\u000a have long suggested the involvement of gibberellin (GA) and abscisic

Mitsunori Seo; Eiji Nambara; Giltsu Choi; Shinjiro Yamaguchi

2009-01-01

59

Multiple Forms of Acidic Endopeptidase from Germinated Barley 1  

PubMed Central

An endopeptidase preparation from germinated barley Hordeum vulgare L., cv. Trophy, purified by affinity chromatography and density-gradient electrofocusing, consisted of three or four components. The preparation was only partly resolved by electrofocusing, with evidence of three possible components (pI 4.15, 4.28, and 4.37). Gel filtration on Sephadex G-75 yielded an asymmetrical peak, the major part of which corresponded to a molecular weight of 14,100, with evidence of one larger and two smaller components. The activity of the preparation was sulfhydryl-dependent; cysteine was the most effective of several sulfhydryl compounds tested. The preparation was sensitive to O2 in the absence of metal chelating agents and was inhibited by sulfhydryl reagents. It showed very narrow concentration tolerances for both cysteine and a substrate, N,N-dimethylhemoglobin. The Km value on N,N-dimethylhemoglobin at pH 3.8 was 0.064 to 0.067% (w/v) substrate; Vmax was 0.80 to 0.83 A340 per hour. Normal enzyme activity and molecular-size distribution were observed when the endopeptidases were extracted in the inhibited state and subsequently reactivated, thus ruling out the possibility that the enzymes might be autolytic artifacts that arose during extraction and purification. PMID:16658456

Burger, W. C.

1973-01-01

60

Germination of 151-year old Acacia spp. seeds  

Microsoft Academic Search

A collection of seeds from five Acacia species was made in Egypt in 1856. Since then, the seeds have been stored at room temperature in different Swedish museums.\\u000a Due to the extreme longevity within the seeds of Acacia and related species, germination tests were performed on the now 151-year old seed. Seeds of two of the five species tested\\u000a germinated.

Matti W. Leino; Johan Edqvist

2010-01-01

61

Role of H2O2 in pea seed germination  

PubMed Central

The imbibition of pea seeds with hydrogen peroxide (H2O2) increased the germination as well as the seedling growth, producing an invigoration of the seeds. We propose that H2O2 could acts as signaling molecule in the beginning of seed germination involving specific changes at proteomic, transcriptomic and hormonal levels. These findings have practical implication in the context of seed priming technologies to invigorate low vigour seeds. PMID:22415047

Barba-Espín, Gregorio; Hernández, José Antonio; Diaz-Vivancos, Pedro

2012-01-01

62

Transcriptional regulatory programs underlying barley germination and regulatory functions of Gibberellin and abscisic acid  

Microsoft Academic Search

Background  Seed germination is a complex multi-stage developmental process, and mainly accomplished through concerted activities of many\\u000a gene products and biological pathways that are often subjected to strict developmental regulation. Gibberellins (GA) and abscisic\\u000a acid (ABA) are two key phytohormones regulating seed germination and seedling growth. However, transcriptional regulatory\\u000a networks underlying seed germination and its associated biological pathways are largely unknown.

Yong-Qiang An; Li Lin

2011-01-01

63

Protein repair L-isoaspartyl methyltransferase in plants. Phylogenetic distribution and the accumulation of substrate proteins in aged barley seeds.  

PubMed Central

Protein L-isoaspartate (D-aspartate) O-methyltransferases (MTs; EC 2.1.1.77) can initiate the conversion of detrimental L-isoaspartyl residues in spontaneously damaged proteins to normal L-aspartyl residues. We detected this enzyme in 45 species from 23 families representing most of the divisions of the plant kingdom. MT activity is often localized in seeds, suggesting that it has a role in their maturation, quiescence, and germination. The relationship among MT activity, the accumulation of abnormal protein L-isoaspartyl residues, and seed viability was explored in barley (Hordeum vulgare cultivar Himalaya) seeds, which contain high levels of MT. Natural aging of barley seeds for 17 years resulted in a significant reduction in MT activity and in seed viability, coupled with increased levels of "unrepaired" L-isoaspartyl residues. In seeds heated to accelerate aging, we found no reduction of MT activity, but we did observe decreased seed viability and the accumulation of isoaspartyl residues. Among populations of accelerated aged seed, those possessing the highest levels of L-isoaspartyl-containing proteins had the lowest germination percentages. These results suggest that the MT present in seeds cannot efficiently repair all spontaneously damaged proteins containing altered aspartyl residues, and their accumulation during aging may contribute to the loss of seed viability. PMID:9414558

Mudgett, M B; Lowenson, J D; Clarke, S

1997-01-01

64

Seed germination in temperate rain forest species of southern Chile: chilling and gap-dependency germination  

Microsoft Academic Search

Canopy gap and chilling requirements for seed germination were assessed in 61 and 44 species, respectively, in the temperate\\u000a rain forest of southern Chile. Germination assays within canopy gap and understorey were carried out under natural conditions.\\u000a Germination tests in cold stratified and non-stratified seeds were performed under laboratory conditions. Seeds were collected\\u000a of common trees, shrubs, vines and perennial

Javier A. Figueroa

2003-01-01

65

A Role for Barley CRYPTOCHROME1 in Light Regulation of Grain Dormancy and Germination[W][OPEN  

PubMed Central

It is well known that abscisic acid (ABA) plays a central role in the regulation of seed dormancy and that transcriptional regulation of genes encoding ABA biosynthetic and degradation enzymes is responsible for determining ABA content. However, little is known about the upstream signaling pathways impinging on transcription to ultimately regulate ABA content or how environmental signals (e.g., light and cold) might direct such expression in grains. Our previous studies indicated that light is a key environmental signal inhibiting germination in dormant grains of barley (Hordeum vulgare), wheat (Triticum aestivum), and Brachypodium distachyon and that this effect attenuates as after-ripening progresses further. We found that the blue component of the light spectrum inhibits completion of germination in barley by inducing the expression of the ABA biosynthetic gene 9-cis-epoxycarotenoid dioxygenase and dampening expression of ABA 8’-hydroxylase, thus increasing ABA content in the grain. We have now created barley transgenic lines downregulating the genes encoding the blue light receptors CRYTOCHROME (CRY1) and CRY2. Our results demonstrate that CRY1 is the key receptor perceiving and transducing the blue light signal in dormant grains. PMID:24642944

Barrero, Jose M.; Downie, A. Bruce; Xu, Qian; Gubler, Frank

2014-01-01

66

Seed fall and field germination of needlerush, Juncus effusus L  

Microsoft Academic Search

Juncus effusus seed fall during one growing season was determined by use of seed traps in a freshwater emergent wetland. These observations provided in situ seed fall estimates of ?4.0 million seeds per square m within the growing season, only 5% of which germinated during the 3-month field study, presumably because of unfavorable environmental conditions. Estimated biomass of seeds collected

Gary N. Ervin; Robert G. Wetzel

2001-01-01

67

Seed germination characteristics of Chrysothamnus nauseosus ssp. viridulus (Astereae, Asteraceae)  

SciTech Connect

Rubber rabbitbrush (Chrysothamnus nauseosus (Pallas) Britt. ssp. viridulus) may prove to be a source of high-quality cis-isoprene rubber, but its establishment is limited by a lack of information on seed germination. Consequently, seeds were germinated at alternating temperatures (5-15, 5-25, 15-25, and 20-30 C) in light and dark as well as constant temperatures (15-40 C with 5-C increments) to determine temperature response. Seeds were also germinated in solutions of polyethylene glycol 6000, salinity regimes at all the above-mentioned temperatures to determine salinity and temperature interaction. The hormones GA/sub 3/ and kinetin were used to study their effect on overcoming salt- and temperature-induced germination inhibition. Seeds of C. nauseosus ssp. viridulus were very sensitive to low temperature. Best germination was achieved at 25 and 30 C, but these seeds also germinated at a higher temperature (35 C). The seeds of rabbit brush germinated at both constant and alternating temperatures. Light appears to play little or no role in controlling germination of the seeds of rubber rabbitbrush. However, seeds of rabbitbrush were sensitive to salinity, and seed germination was progressively inhibited by increase in salt concentration, although a few seeds still germinated at the highest saline level. Progressively higher concentrations of polyethylene glycol also progressively inhibited germination. Suppression of seed germination induced by high salt concentrations and high temperatures can be partially alleviated by the application of either GA/sub 3/ or kinetin. 34 references, 5 figures, 3 tables.

Khan, M.A.; Sankhla, N.; Weber, D.J.; McArthur, E.D.

1987-04-30

68

Germination ecology and seed population dynamics of Digitalis purpurea  

Microsoft Academic Search

The germination ecology and the dynamics of the generative reproduction in populations of Digitalis purpurea L. were investigated in the field as well as in experiments. Germination of fresh seeds in the dark on moist filter paper appeared to differ between populations. These differences were eliminated when a moist natural soil functioned as germination substrate. An interaction between the spectral

J. van Baalen

1982-01-01

69

Phylogenetically distant barley legumains have a role in both seed and vegetative tissues.  

PubMed

Legumains or vacuolar processing enzymes are cysteine peptidases (C13 family, clan CD) with increasingly recognized physiological significance in plants. They have previously been classified as seed and vegetative legumains. In this work, the entire barley legumain family is described. The eight members of this family belong to the two phylogenetic clades in which the angiosperm legumains are distributed. An in-depth molecular and functional characterization of a barley legumain from each group, HvLeg-2 and HvLeg-4, was performed. Both legumains contained a signal peptide and were located in the endoplasmic reticulum, were expressed in seeds and vegetative tissues, and when expressed as recombinant proteins showed legumain and caspase proteolytic activities. However, the role of each protein seemed to be different in their target tissues. HvLeg-2 responded in leaves to biotic and abiotic stimuli, such as salicylic acid, jasmonic acid, nitric oxide, abscisic acid, and aphid infestation, and was induced by gibberellic acid in seeds, where the protein is able to degrade storage globulins. HvLeg-4 responded in leaves to wounding, nitric oxide, and abscisic acid treatments, and had an unknown role in the germinating seed. From these results, a multifunctional role was assumed for these two phylogenetically distant legumains, achieving different physiological functions in both seed and vegetative tissues. PMID:23669572

Julián, Israel; Gandullo, Jacinto; Santos-Silva, Ludier K; Diaz, Isabel; Martinez, Manuel

2013-07-01

70

Phytotoxicity of nanoparticles: Inhibition of seed germination and root growth  

Microsoft Academic Search

Plants need to be included to develop a comprehensive toxicity profile for nanoparticles. Effects of five types of nanoparticles (multi-walled carbon nanotube, aluminum, alumina, zinc, and zinc oxide) on seed germination and root growth of six higher plant species (radish, rape, ryegrass, lettuce, corn, and cucumber) were investigated. Seed germination was not affected except for the inhibition of nanoscale zinc

Daohui Lin; Baoshan Xing

2007-01-01

71

Effect of fungicide on Wyoming big sagebrush seed germination  

Microsoft Academic Search

Germination tests of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young [Asteraceae]) seeds often exhibit fungal contamination, but the use of fungicides should be avoided because fungicides may artificially inhibit germination. We tested the effect of seed-applied fungicides on germination of Wyoming big sagebrush at 2 different water potentials (-0.033 and -0.7 MPa) and found that treating

Robert D Cox; Lance H Kosberg; Nancy L Shaw; Stuart P Hardegree

2011-01-01

72

Effect of fungicide on Wyoming big sagebrush seed germination  

Microsoft Academic Search

:Germination tests of Wyoming big sagebrush (Artemisia tridentata Nutt. ssp. wyomingensis Beetle & Young [Asteraceae]) seeds often exhibit fungal contamination, but the use of fungicides should be avoided because fungicides may artificially inhibit germination. We tested the effect of seed-applied fungicides on germination of Wyoming big sagebrush at 2 different water potentials (-0.033 and -0.7 MPa) and found that treating

Robert D Cox; Lance H Kosberg; Nancy L Shaw; Stuart P Hardegree

2011-01-01

73

Smoke-induced seed germination in California chaparral  

USGS Publications Warehouse

The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that smoke also induces germination in these same species. Smoke is highly effective, often inducing 100% germination in deeply dormant seed populations with 0% control germination. Smoke induces germination both directly and indirectly by aqueous or gaseous transfer from soil to seeds. Neither nitrate nor ammonium ions were effective in stimulating germination of smoke-stimulated species, nor were most of the quantitatively important gases generated by biomass smoke. Nitrogen dioxide, however, was very effective at inducing germination in Caulanthus heterophyllus (Brassicaceae), Emmenanthe penduliflora (Hydrophyllaceae), Phacelia grandiflora (Hydrophyllaceae), and Silene multinervia (Caryophyllaceae). Three species, Dendromecon rigida (Papaveraceae), Dicentra chrysantha, and Trichostema lanatum (Lamiaceae), failed to germinate unless smoke treatment was coupled with prior treatment of 1 yr soil storage. Smoke-stimulated germination was found in 25 chaparral species, representing 11 families, none of which were families known for heat-shock-stimulated germination. Seeds of smoke-stimulated species have many analogous characteristics that separate them from most heat-shock-stimulated seeds, including: (1) outer seed coats that are highly textured, (2) a poorly developed outer cuticle, (3) absence of a dense palisade tissue in the seed coat, and (4) a subdermal membrane that is semipermeable, allowing water passage but blocking entry of large (molecular mass > 500) solutes. Tentative evidence suggests that permeability characteristics of this subdermal layer are altered by smoke. While the mechanism behind smoke-induced germination is not known, it appears that smoke may be involved in overcoming different blocks to germination in different species. For example, in Emmenanthe penduliflora, NO2 in smoke was sufficient to induce germination, and most forms of physical or chemical scarification also induced germination. For Romneya coulteri, NO2 alone failed to induce germination, and scarified seeds required addition of gibberellic acid. In Dicentra chrysantha, none of these treatments, nor smoke alone, induced germination, but germination was triggered by a combination of soil burial followed by smoke treatment. Smoke-stimulated species differed substantially in the duration of smoke exposure required to induce germination, and this was inversely correlated with tolerance to smoke exposure. We suggest that such differences in response may affect postfire community structure.

Keeley, J.E.; Fotheringham, C.J.

1998-01-01

74

Mitochondrial biogenesis in plants during seed germination.  

PubMed

Mitochondria occupy a central role in the eukaryotic cell. In addition to being major sources of cellular energy, mitochondria are also involved in a diverse range of functions including signalling, the synthesis of many essential organic compounds and a role in programmed cell death. The active proliferation and differentiation of mitochondria is termed mitochondrial biogenesis and necessitates the coordinated communication of mitochondrial status within an integrated cellular network. Two models of mitochondrial biogenesis have been defined previously, the growth and division model and the maturation model. The former describes the growth and division of pre-existing mature organelles through a form of binary fission, while the latter describes the propagation of mitochondria from structurally and biochemically simple promitochondrial structures that upon appropriate stimuli, mature into fully functional mitochondria. In the last decade, a number of studies have utilised seed germination in plants as a platform for the examination of the processes occurring during mitochondrial biogenesis. These studies have revealed many new aspects of the tightly regulated procession of events that define mitochondrial biogenesis during this period of rapid development. A model for mitochondrial biogenesis that supports the maturation of mitochondria from promitochondrial structures has emerged, where mitochondrial signalling plays a crucial role in the early steps of seed germination. PMID:24727594

Law, Simon R; Narsai, Reena; Whelan, James

2014-11-01

75

Beta-amylase in germinating millet seeds.  

PubMed

Beta-amylase (EC 3.2.1.2) was isolated from germinating millet (Panicum miliaceum L.) seeds by a procedure that included ammonium sulfate fractionation, chromatography on DEAE-cellulofine and CM-cellulofine, and preparative isoelectric focusing. The enzyme was homogeneous by SDS-PAGE. The M(r) of the enzyme was estimated to be 58,000 based on its mobility on SDS-PAGE and gel filtration with TSKgel G4000SW(XL), which showed that it is composed of a single unit. The isoelectric point of the enzyme was 4.62. The enzyme hydrolyzed malto-oligosaccharides more readily as their degree of polymerization increased, this being strongest for malto-oligosaccharides larger than 13 glucose residues and very weakly for maltotriose. Amylose, amylopectin and soluble starch were the most suitable substrates for the enzyme. While the enzyme showed some activity against native starch by itself, starch digestion was accelerated 2.5-fold using alpha-amylase, pullulanase and alpha-glucosidase. This enzyme appears to be very important for the germination of millet seeds. PMID:14561508

Yamasaki, Yoshiki

2003-11-01

76

EFFECT OF GERMINATION REGULATING CHEMICALS ON SEED GERMINATION OF HALOGETON GLOMERATUS FOR ALLEVIATION OF SALINITY STRESS  

Microsoft Academic Search

Halogeton glomeratus (Bieb.) C.A. Mey (Chenopodiaceae) is an annual forb that is widely distributed in mixed desert shrub, salt desert shrub and pinyon-juniper communities of northern Utah. Halogeton glomeratus seeds gave only 78% germination in distilled water. Fusicoccin (FC) had some effects in partially alleviating innate dormancy while other chemicals had no effect. Seed germination was inhibited with the increases

M. AJMAL KHAN; BILQUEES GUL; DARRELL J. WEBER

2009-01-01

77

Stratifying, partially redrying and storing Douglas-fir seeds : effects on growth and physiology during germination  

E-print Network

the germination percentage of interior-source seeds but hastened germination speed for seeds from both sources seed vigor, as reflected by germination speed and seedling length and dry weight, yet redried seeds with germination speed. Results suggest that it would be advantageous to redry seeds to a range of 25 to 35 p. 100

Paris-Sud XI, Université de

78

Allelopathy due to purine alkaloids in tea seeds during germination  

Microsoft Academic Search

Summary  During imbibition of whole tea seeds (6 days) two purine alkaloids, caffeine and theobromine, did not decrease in the seed\\u000a coats and there was no increase in the seeds. In parallel with and after the breaking of seed coats there was a gradual release\\u000a of caffeine from coats of germinating seeds. By contrast, when the seed was freed from the

T. Suzuki; G. R. Waller

1987-01-01

79

Effects of Gut Passage, Feces, and Seed Handling on Latency and Rate of Germination in Seeds Consumed by  

E-print Network

Effects of Gut Passage, Feces, and Seed Handling on Latency and Rate of Germination in Seeds, and germination rates of 18 species consumed by capuchins. For five of the most commonly swallowed seed species, we determined germination rates and average time to germination (latency) for seeds ingested

Fedigan, Linda M.

80

A Comparison of Factors Involved in Starch Degradation in Barley Germination Under Laboratory and Malting Conditions  

Technology Transfer Automated Retrieval System (TEKTRAN)

Grains of the malting barley cultivar Legacy were laboratory germinated (LG) or micromalted (MM) and sampled daily from 0 to 5 days after imbibition/steeping. Alpha-amylase and beta-amylase activities and protein levels along with starch, osmolyte concentration (OC), and sugar (glucose, sucrose, fr...

81

Pre-treating Seed to Enhance Germination of Desert Shrubs  

SciTech Connect

Creosotebush [Larrea tridentata (D.C.) Cav.] and white bursage [Ambrosia dumosa (A. Gray) W.W. Payne] seeds were subjected to pre-treatments of rinsing and soaking in water and thiourea to enhance germination in laboratory experiments. The effects of darkness, temperature, seed source, and soil moisture were also evaluated in the laboratory. The best pre-treatment from the laboratory experiments, rinsing with water for 36 hours followed by drying, was field-tested at Fort Irwin, California. Two sites and two seeding dates (early March and mid April) were determined for each site. Five mulch treatments (no mulch, straw, gravel, chemical stabilizer, and plastic) were evaluated in combination with the seed pre-treatments. Field emergence was greatly enhanced with the seed pre-treatment for white bursage during the March (18-42% increase in germination) and April seedings (16-23% increase in germination). Creosotebush showed poor germination during March (2-5%) when soil temperatures averaged 15 C, but germination increased during the April trials (6-43%) when soil temperatures averaged 23 C. The seed pre-treatment during the April trials increased germination from 16-23%. The plastic mulch treatment increased germination dramatically during both the March and April trials. The plastic mulch increased soil temperatures (8-10 C)and maintained high humidity during germination. Both the chemical stabilizer and the gravel mulches improved germination over the control while the straw mulch decreased germination. These results suggest that seed pre-treatments combined with irrigation and mulch are effective techniques to establish these two dominant Mojave Desert species from seed.

W. K. Ostler; D. C. Anderson; D. J. Hansen

2002-06-01

82

Factors influencing seed germination in Carex scoparia Schk  

Microsoft Academic Search

Carex scoparia seeds collected in 1985, 1987, and 1988 in a southeastern Wisconsin sedge meadow were used to investigate appropriate storage\\u000a conditions and the influence of two alternating temperature regimes on germination. Seeds collected in 1987 and 1988 stored\\u000a dry at room temperature (dry-warm) had a higher germination at both 21\\/25 C and 25\\/32 C than seed of the same

John L. Larson; Forest W. Stearns

1990-01-01

83

Germination of Cynara seeds ; effect of light and temperature and function of the endosperm  

E-print Network

Germination of Cynara seeds ; effect of light and temperature and function of the endosperm Yehuda SUMMARY The germination behaviour of globe artichoke (Cynara scolymus L.) seeds is described. Germination of this tissue did not affect subsequent germination at 20° of seeds which previously failed to germinate at 30

Paris-Sud XI, Université de

84

Successful Seed Germination of the Nickel Hyperaccumulator Stackhousia tryonii  

PubMed Central

• Background and Aims Stackhousia tryonii, a rare nickel hyperaccumulating herb, is endemic to ultramafic (serpentine) soils of central Queensland, Australia. The effects of eight dormancy-relieving treatments on germination of stored seeds of Stackhousia tryonii were investigated under controlled light and temperature conditions. • Methods The treatments were: untreated (control i), leached and dehydrated (primed control ii), treating with gibberellic acid (150 and 300 µM), smoke extract (5 and 10 %, v/v) and potassium cyanide (40 and 80?mM). • Key Results Freshly harvested seeds did not germinate. Germination percentage increased with time of storage for up to 18 months (38·3 %). Gibberellin, smoke extract and cyanide treatments did not significantly improve germination. Light did not affect seed germination and there was no interaction between dormancy-relieving treatments and light. A significant inhibition of germination occurred in seeds treated with 5 % (but not 10 %) aqueous smoke extract. Saturated fatty acids, predominantly tridecanoic (C13:0), constituted about 90 % of the total fatty acids in the oil of freshly harvested seeds. In contrast, there was increased accumulation (>75 %) of mono-unsaturated (oleic, C18:1) and poly-unsaturated (linoleic, C18:2; linolenic, C18:3) fatty acids in the oil of stored seeds. • Conclusions Seeds of S. tryonii require an after-ripening period for germination. PMID:15840638

BHATIA, NAVEEN P.; NKANG, ANI E.; WALSH, KERRY B.; BAKER, ALAN J. M.; ASHWATH, NANJAPPA; MIDMORE, DAVID J.

2005-01-01

85

Volatile Metabolites Controlling Germination in Buried Weed Seeds  

PubMed Central

Velvetleaf (Abutilon theophrasti Medic), morning glory (Ipomoea purpurea [L.] Roth), and wild mustard (Brassica kaber [D.C.] L. C. Wheeler) seeds exhibited decreased germination with increased planting depth in soil. Flushing the soil for 2 minutes each day with air overcame the inhibition. A sealed in vitro system was used to sample the volatile components produced by weed seeds. Inhibition of seed germination was accompanied by decreased O2 levels and production of volatile metabolites identified as acetaldehyde, ethanol, and acetone. The effectiveness of these compounds in reducing germination was dependent on O2 levels. PMID:16658159

Holm, Robert E.

1972-01-01

86

MATURITY AND TEMPERATURE AFFECTS THE GERMINATION OF STYRAX JAPONICUS SEEDS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effect of seed maturity, warm (18oC) or cold (5.5oC) temperature, and gibberellic acid (GA3) on seed germination of Styrax japonicus Sieb. et. Zucc was investigated. Seed maturity and morphological changes were observed using magnetic resonance (MR) imaging (MRI). Fruits harvested on July 22,...

87

Trace gas emissions and smoke-induced seed germination  

Microsoft Academic Search

Dormant seeds of a California chaparral annual were induced to germinate by smoke or paper. Nitrogen oxides induced 100 percent vapors emitted from smoke-treated sand or treated water samples inducing. Smoke germination in a manner similar to smoke germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NOâ)-treated samples. Vapors from smoke-treated and NOâ-treated filter

Jon E. Keeley; C. J. Fotheringham

1997-01-01

88

Morphology, physiology and environmental effects of triploid watermelon seed germination  

E-print Network

Subject: Horticulture ABSTRACT Morphology, Physiology and Environmental Effects of Triploid Watermelon Seed Germination (May 2001) Stacie Lee Grange, B. S. California Polytechnic State University, San Luis Obispo Co-Chairs of Advisory Committee' Dr...

Grange, Stacie Lee

2001-01-01

89

Photocontrol of seed germination in Impatiens wallerana Hook. f  

Microsoft Academic Search

General characteristics of light sensitivity of Impatients wallerana seeds were investigated. Germination was absolutely dependent on light, irrespective of temperature. High percentages of germination were obtained by exposure to long periods of illumination or, alternatively, to several repeated short irradiations with red light. In this case, responsiveness to light was not altered by increasing either the initial incubation period in

Rogeria Pereira de Souza; Maria de Fátima A. Pereira

1994-01-01

90

Salinity and seed germination patterns in coastal plants  

Microsoft Academic Search

The seed germination behaviour of a number of coastal species suggests that they can be separated into three categories, whose response to salinity shows some correlation with habitat. All but two germinated well in fresh water. After immersion for several days in 1\\/2, full, and 1 1\\/2 strength seawater all recover at least partly. Dune species are more adversely affected

S. R. J. Woodell

1985-01-01

91

DISPERSAL OF WETLAND PLANT SEEDS BY MALLARDS: INFLUENCE OF GUT PASSAGE ON RECOVERY, RETENTION, AND GERMINATION  

E-print Network

, retention time, and germination for the seeds of 10 wetland plant species (Chenopodium album, Digitaria and fed each seed species in each trial, and included germination controls of non-consumed seeds. Overall, 19.0 6 1.8% (mean 6 SE) of seeds were recovered and of recovered seeds 7.6 6 1.2% germinated

Dugger, Bruce

92

A shotgun phosphoproteomics analysis of embryos in germinated maize seeds  

Microsoft Academic Search

To better understand the role that reversible protein phosphorylation plays in seed germination, we initiated a phosphoproteomic\\u000a investigation of embryos of germinated maize seeds. A total of 776 proteins including 39 kinases, 16 phosphatases, and 33\\u000a phosphoproteins containing 36 precise in vivo phosphorylation sites were identified. All the phosphorylation sites identified,\\u000a with the exception of the phosphorylation site on HSP22,

Tian-Cong Lu; Ling-Bo Meng; Chuan-Ping Yang; Gui-Feng Liu; Guan-Jun Liu; Wei Ma; Bai-Chen Wang

2008-01-01

93

G Protein Signaling in the Regulation of Arabidopsis Seed Germination  

NSDL National Science Digital Library

Seed germination and early seedling growth are regulated by an intricate network of hormonal signaling pathways. The plant hormones gibberellic acid (GA) and brassinosteroids (BRs) are important positive regulators of these processes, whereas the hormone abscisic acid (ABA) is a potent negative regulator. In Arabidopsis, analysis of mutant plants has implicated heterotrimeric guanine nucleotide-binding protein (G protein) components in regulation of seed germination by all three of these hormones.

Sarah M. Assmann (Penn State University;Biology Department REV)

2005-11-01

94

Gibberellin Biosynthesis and Response during Arabidopsis Seed Germination  

Microsoft Academic Search

The hormone-mediated control of plant growth and development involves both synthesis and response. Previous studies have shown that gibberellin (GA) plays an essential role in Arabidopsis seed germination. To learn how GA stimulates seed germination, we performed comprehensive analyses of GA biosynthesis and response using gas chromatography-mass spectrometry and oligonucleotide-based DNA microarray analysis. In addition, spatial correlations between GA biosynthe-

Mikihiro Ogawa; Atsushi Hanada; Yukika Yamauchi; Ayuko Kuwahara; Yuji Kamiya; Shinjiro Yamaguchi

2003-01-01

95

Proteomic analysis of Arabidopsis seed germination and priming  

Microsoft Academic Search

To better understand seed germination, a complex developmental process, we developed a proteome analysis of the model plant Arabidopsis for which complete genome sequence is now available. Among about 1,300 total seed proteins resolved in two-dimensional gels, changes in the abundance (up- and down-regulation) of 74 proteins were observed during germination sensu stricto (i.e. prior to radicle emergence) and the

Karine Gallardo; Claudette Job; Steven P. C. Groot; Magda Puype; Hans Demol; Joel Vandekerckhove; Dominique Job

2001-01-01

96

Ecological genetics of seed germination regulation in Bromus tectorum L  

Microsoft Academic Search

Regulation of seed germination phenology is an important aspect of the life history strategy of invading annual plant species.\\u000a In the obligately selfing winter annual grass Bromus tectorum, seeds are at least conditionally dormant at dispersal in early summer and lose dormancy through dry-afterripening. Patterns\\u000a of germination response at dispersal vary among populations and sometimes across years within populations. To

Susan E. Meyer; Phil S. Allen

1999-01-01

97

Effect of pre-germination treatments on seed physiology and germination of central Himalayan oaks?  

Microsoft Academic Search

The continuous decline in regeneration of two important species of central Himalayan oak, namely Quercus glauca and Q. leucotrichophora, is of great concern. A study was therefore, carried out to improve germination ability of these species using various presoaking\\u000a treatments. Seeds of both the species lost viability following storage; tetrazolium staining pattern and germination capacity\\u000a of seeds following different period

Vijay K. Purohit; L. M. S. Palni; Shyamal K. Nandi

2009-01-01

98

A RING finger E3 ligase gene, Oryza sativa Delayed Seed Germination 1 (OsDSG1), controls seed germination and stress responses in rice  

Microsoft Academic Search

Seed germination is an important character for plant growth and seed quality. We identified a rice mutant that was delayed\\u000a in its germination. There, T-DNA was inserted into Oryza sativa Delayed Seed Germination 1 (OsDSG1), causing a recessive null mutation. Overexpression of the gene enhanced seed germination. OsDSG1 is most similar to Arabidopsis AIP2, an E3 ligase targeting ABI3.Yeast two-hybrid

Gi-Gyeong Park; Jong-Jin Park; Jinmi Yoon; Sun-Nam Yu; Gynheung An

2010-01-01

99

The restoration of sedge meadows: seed viability, seed germination requirements, and seedling growth of Carex species  

Microsoft Academic Search

To better understand how to establishCarex species from seed in created and restored wetlands, a series of experimental studies was conducted onCarex seed and seedlings. These studies included (1) the effect of seed age (1 to 18 months after collection) on viability and\\u000a germination, (2) storage conditions (+4,-4 or +4\\/-4°C; wet or dry) on seed germination, (3) soil moisture on

Arnold G. van der Valk; Tony L. Bremholm; Elizabeth Gordon

1999-01-01

100

Quantifying the oxygen sensitivity of seed germination using a population-based threshold model  

E-print Network

Quantifying the oxygen sensitivity of seed germination using a population-based threshold model, F-75252 Paris cedex 05, France Abstract Seeds vary widely in the sensitivity of germination status of the seeds. Most analyses of the O2 sensitivity of germination have focused on final germination

Bradford, Kent

101

Aquatic Botany 66 (2000) 169180 Seed germination of two Everglades species, Cladium  

E-print Network

Aquatic Botany 66 (2000) 169­180 Seed germination of two Everglades species, Cladium jamaicense block design. The average incubation period needed for seeds to germinate was shorter for T. domingensis for T. domingensis seeds to germinate, whereas C. jamaicense could germinate at a reduced rate

Brix, Hans

102

Proteins induced by salt stress in tomato germinating seeds  

SciTech Connect

Salt effects on protein synthesis in tomato germinating seeds were investigated by two-dimensional polyacrilamide gel electrophoresis of proteins labeled in vivo with ({sup 35}S)-Methionine. Seeds germinating in NaCl were analyzed at three germination stages (4mm long radicals, 15mm long radicles and expanding cotyledons) and compared to those germinating in water. At the first germination stage several basic proteins of M.W. 13Kd, 16Kd, 17Kd and 18Kd were detected in only salt germinating seeds. Other basic proteins of M.W. 12Kd, 50Kd and 54Kd were salt-induced at the second and third stage of germination. One 14Kd acid protein is observed in every assayed stage and shows several phosphorylated forms. The levels of expression of these proteins are directly correlated to assayed NaCl concentrations. All of these proteins, except 17Kd, are also induced by abscisic acid (ABA) in the same germination stages. A cooperative effect on the synthesis of these proteins is observed when both ABA and NaCl are present.

Torres-Shumann, S.; Godoy, J.A.; del Pozo, O.; Pintor-Toro, J.A. (Instituto Recursos Naturales y Agrobiologia, Sevilla (Spain))

1989-04-01

103

Trace gas emissions and smoke-induced seed germination  

SciTech Connect

Dormant seeds of a California chaparral annual were induced to germinate by smoke or paper. Nitrogen oxides induced 100 percent vapors emitted from smoke-treated sand or treated water samples inducing. Smoke germination in a manner similar to smoke germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NO{sub 2})-treated samples. Vapors from smoke-treated and NO{sub 2}-treated filter paper had comparable NO{sub 2} flux rates. Chaparral wildfires generate sufficient nitrogen oxides from combustion of organic matter or from postfire biogenic nitrification to trigger germination of Emmerianthe penduliflora. Nitrogen oxide-triggered germination is not the result of changes in imbibition, as is the case with heat stimulated seeds.

Keeley, J.E.; Fotheringham, C.J. [Occidental College, Los Angeles, CA (United States)] [Occidental College, Los Angeles, CA (United States)

1997-05-23

104

Effect of seed stimulation on germination and sugar beet yield  

NASA Astrophysics Data System (ADS)

Germination and sugar beet yield after seed stimulation were investigated. The seeds came from the energ'hill technology and were subject to laser irradiation. The experiments were conducted in the laboratory and field conditions. Lengthening of germinal roots and hypocotyls was observed. A positive effect of the stimulation on the morphological features was observed for the Eh seeds and laser irradiation applied in a three-fold dose. The energ'hill seeds exhibited a significantly higher content of carotenoids in seedlings and an increase in the content of chlorophylls. Laser light irradiation favourably modified the ratio of chlorophyll a to b. The leaves and roots of plants developed from the energ'hill and irradiated seeds were characterized by higher dry matter content thanin non-stimulated seeds. Seed stimulation had a positive influence on yielding and the saccharose content.

Pro?ba-Bia?czyk, U.; Szajsner, H.; Grzy?, E.; Demczuk, A.; Saca?a, E.; B?k, K.

2013-03-01

105

Mechanism and Control of Solanum lycocarpum Seed Germination  

PubMed Central

Background and Aims Solanaceae seed morphology and physiology have been widely studied but mainly in domesticated crops. The present study aimed to compare the seed morphology and the physiology of germination of Solanum lycocarpum, an important species native to the Brazilian Cerrado, with two species with endospermic seeds, tomato and coffee. Methods Morphological parameters of fruits and seeds were determined by microscopy. Germination was monitored for 40 d under different temperature regimes. Endosperm digestion and resistance, with endo-?-mannanase activity and required force to puncture the endosperm cap as respective markers, were measured during germination in water and in abscisic acid. Key Results Fruits of S. lycocarpum contain dormant seeds before natural dispersion. The best germination condition found was a 12-h alternating light/dark and high/low (20/30 °C) temperature cycle, which seemed to target properties of the endosperm cap. The endosperm cap contains 7–8 layers of elongated polygonal cells and is predestined to facilitate radicle protrusion. The force required to puncture the endosperm cap decreased in two stages during germination and showed a significant negative correlation with endo-?-mannanase activity. As a result of the thick endosperm cap, the puncture force was significantly higher in S. lycocarpum than in tomato and coffee. Endo-?-mannanase activity was detected in the endosperm cap prior to radicle protrusion. Abscisic acid inhibited germination, increase of embryo weight during imbibition, the second stage of weakening of the endosperm cap and of endo-?-mannanase activity in the endosperm cap. Conclusions The germination mechanism of S. lycocarpum bears resemblance to that of tomato and coffee seeds. However, quantitative differences were observed in embryo pressure potential, endo-?-mannanase activity and endosperm cap resistance that were related to germination rates across the three species. PMID:17855380

Pinto, Lilian V. A.; Da silva, Edvaldo A. A.; Davide, Antonio C.; De Jesus, Valquíria A. Mendes; Toorop, Peter E.; Hilhorst, Henk W. M.

2007-01-01

106

Amylolytic activity in germinated Agrostemma githago L. seeds  

Microsoft Academic Search

The perisperm of seeds of Agrostemma githago contains starch reserves which constitute 40% of the dry weight of the mature seed. These starch reserves were mostly broken down between 48 and 96 h after initiation of imbibition. (Germination occurred after 24 h.) The mode of starch degradation showed close parallels with the breakdown of the starchy endosperm in cereals. Thus,

G. J. Klerk; P. Willekens; H. Kok; J. V. Jacobsen

1986-01-01

107

Seed longevity and fire: germination responses of an exotic perennial herb in NW Patagonian grasslands (Argentina).  

PubMed

Fire affects grassland composition by selectively influencing recruitment. Some exotic species can increase their abundance as a consequence of fire-stimulated seed germination, but response may depend on seed age. Rumex acetosella L. (Polygonaceae, sheep's sorrel) is a cosmopolitan herb that has invaded NW Patagonia's grasslands. This species forms persistent soil seed banks and increases after disturbances, particularly fire. We studied how fire and seed longevity influence R. acetosella germination. In 2008, we conducted laboratory experiments where we exposed different-aged seeds (up to 19 years old) to heat, smoke, charcoal, ash and control treatments. Total percentage germination and mean germination time depended on both seed age and fire treatment. Germination of younger seeds decreased with increasing temperature. There was no general pattern in germination responses of different-aged seeds to smoke, charcoal and ash. While smoke improved the germination of fresh seeds, charcoal decreased germination. Germination of untreated seeds was negatively correlated with seed age, and mean germination time increased with seed age. In most treatments, fresh seeds had lower germination than 1-5-year-old seeds, indicating an after-ripening requirement. Smoke stimulates R. acetosella germination, causing successful recruitment during post-fire conditions. Fresh seeds are particularly responsive to fire factors, possibly because they have not experienced physical degradation and are more receptive to environmental stimuli. Knowing the colonisation potential from the soil seed bank of this species during post-fire conditions will allow us to predict their impact on native communities. PMID:21973326

Franzese, J; Ghermandi, L

2011-11-01

108

Seed depth and pathogens affect fatal germination of velvetleaf and giant foxtail  

Technology Transfer Automated Retrieval System (TEKTRAN)

Fatal germination of weed seeds occurs when a weed seed initiates germination, but the seedling does not reach the soil surface. Bioassays of velvetleaf and giant foxtail seed fate in Michigan field soil were used to determine the role of pathogenic fungi and seed burial depth in fatal germination ...

109

7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.  

...2014-01-01 false Germination of vegetable seed in containers of 1 pound...Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1 pound...Each variety of vegetable seed which has a germination percentage less...

2014-01-01

110

7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 false Germination of vegetable seed in containers of 1 pound...Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1 pound...Each variety of vegetable seed which has a germination percentage less...

2012-01-01

111

Germination and storage of recalcitrant seeds of some tropical forest tree species  

E-print Network

Germination and storage of recalcitrant seeds of some tropical forest tree species F. Corbineau D and Roberts, 1979). The aim of the present study was to analyze the germination of some recalci- trant seeds of freshly harvested seeds Freshly harvested seeds had no dorman- cy. In all cases, germination was best

Paris-Sud XI, Université de

112

7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Germination of vegetable seed in containers of 1 pound...Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1 pound...Each variety of vegetable seed which has a germination percentage less...

2011-01-01

113

7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 false Germination of vegetable seed in containers of 1 pound...Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1 pound...Each variety of vegetable seed which has a germination percentage less...

2013-01-01

114

Action of plant growth regulators and salinity on seed germination of Ceratoides lanata  

Microsoft Academic Search

Ceratoides lanata (Pursh) J.T. Howell is a shrub with numerous annual branchlets from the family Chenopodiaceae and is widely distributed in brackish water playas of northern Utah. Seeds had no dormancy, and about 90% of the seeds germinated in nonsaline control. Seed germination decreased with the increase in salinity, and more than 10% of the seeds germinated at 900 mmol\\/L

M. Ajmal Khan; Bilquees Gul; Darrell J. Weber

2004-01-01

115

Serine proteinases from barley malt may degrade beta-amylase  

Technology Transfer Automated Retrieval System (TEKTRAN)

Barley seed proteinases are critically important to seed germination and malting in that they generate amino acids from seed N reserves, supporting embryo growth during germination and yeast fermentation during brewing. However, relatively little is known regarding the endogenous protein substrate ...

116

Characterization of Percent Seed Germination for Native Switchgrass Accessions Collected from New York, Pennsylvania, and the Northeast  

E-print Network

Characterization of Percent Seed Germination for Native Switchgrass Accessions collected in both 2010 and 2011. In 2010, seed lots from each plant were germinated/15C night). In 2011, all seed lots were germinated at the standard temperatures

Pawlowski, Wojtek

117

Repression of AUXIN RESPONSE FACTOR10 by microRNA160 is critical for seed germination and  

E-print Network

Repression of AUXIN RESPONSE FACTOR10 by microRNA160 is critical for seed germination and post-germination important roles in seed germination and post-germination. Transgenic plants expressing an miR160-resistant sensu stricto germination and post-germination, mARF10 mutant seeds and plants were hypersensitive

Montgomery, Tai

118

Seed germination of five mountain steppe species of Central Asia  

Microsoft Academic Search

This paper presents data on the germination traits of five perennials (Allium polyrrhizum, Agropyron cristatum, Arenaria meyeri, Artemisia frigida and Artemisia santolinifolia) widespread in the mountain steppes of southern Mongolia. Germination and seed viability were assessed at three alternate temperatures (8\\/4°C, 20\\/10°C, 32\\/20°C), three levels of osmotic stress (deionized water; ?0.5MPa, ?1MPa Mannitol solution), and under conditions of alternate light\\/darkness

K. Ronnenberg; K. Wesche; M. Pietsch; I. Hensen

2007-01-01

119

Rapid and High Seed Germination and Large Soil Seed Bank of Senecio aquaticus in Managed Grassland  

PubMed Central

Senecio aquaticus, regionally a Red List species in Europe, has become increasingly abundant in agricultural grassland of medium to high management intensity in Switzerland, Southern Germany, and Austria in recent years, where it is a threat for animal and human health due to its toxicity. In this study, we investigated the seed ecology of S. aquaticus to help protection of the species in relic populations while improving its control when abundant in managed grassland. Germination percentages of fresh ripe seeds of S. aquaticus were on average 68% in 2008, but only 45% in 2010, indicating yearly variation. Germination was generally fast: ten days after the onset of the tests, often more than 45% of all seeds had germinated. When covered with a soil layer of 5?mm, germination was only 16% compared to 63% in full light. Seeds buried in the soil for one and two years showed a germination of 78%, significantly higher than that of fresh ripe seeds, thus suggesting a stimulating effect of cold-wet stratification on germination and long seed survival in the soil. In grasslands with established populations of S. aquaticus, the number of germinable seeds of the species ranged from 361 to 1875?m?2 in topsoil (0–10?cm) with an average of 1139?m?2. The large seed bank and the rapid and high germination of S. aquaticus suggest that allowing seed formation is important for its preservation in relic populations. With respect to agricultural grassland, strategies to control the species should initially target hindering seed production and dispersal. PMID:22272180

Suter, Matthias; Lüscher, Andreas

2012-01-01

120

Protein changes during ethanol induced seed germination in Aconitum heterophyllum.  

PubMed

Aconitum heterophyllum is a high altitude medicinal plant that has become endangered due to overexploitation for their aconitins. The most effective, conventional propagation method for any plant species is by seed. However, in Aconitum seed germination is erratic, and seedling survival is low. In the present study results have been discussed on the possible implication of ethanol treatment on removal of barriers on radical emergence in terms of protein changes. Eighty seven percent of seed germination was achieved in Aconitum with ethanol treatment. Comparative 2-DE analysis of ethanol treated and untreated seed protein profiles in Phase II of germination revealed 40 differentially expressed proteins. Twenty-seven out of 40 proteins were induced, 5 were increased and 8 were repressed. Mass spectrometry and subsequent identification confirmed that these proteins were involved in metabolism, DNA regulation, stress tolerance and plasmamembrane/cell wall biosynthesis/extension processes. These protein changes might be responsible for physiological and physical changes, respectively, resulted in increase in germination percentage. Further, characterization of these proteins will be of great help in understanding the molecular mechanism lying behind enhanced germination in response to ethanol treatment. PMID:23199684

Rana, Bindu; Sreenivasulu, Yelam

2013-01-01

121

Investigation of germination and aging in Moravian III barley grain by nuclear magnetic resonance.  

PubMed Central

High-resolution, solid-state 1H nuclear magnetic resonance (NMR) techniques are used for the first time to study germination in imbibed Moravian III barley grains. Whereas magic-angle spinning 1H NMR spectra reveal the water and lipid components in barley grains, combined rotation and multiple-pulse spectroscopy techniques provide 1H NMR spectra of grains that reveal the protein and carbohydrate as well as the water and lipid components. Spectra of grains are compared with spectra of model compounds to verify assignments. 1H T1 and T2 measurements using magic-angle spinning only and combined rotation and multiple-pulse spectroscopy techniques provide information about molecular mobility within the grains during inhibition. Some grains were subjected to artificial aging conditions. 1H NMR spectral comparisons are made between normal, viable grains and artificially aged grains. PMID:8770229

Ridenour, C F; Xiong, J; Maciel, G E

1996-01-01

122

Oxygen Consumption by Germinating Seeds Advisor: Dr. Neil Budko (n.v.budko@tudelft.nl)  

E-print Network

Oxygen Consumption by Germinating Seeds Advisor: Dr. Neil Budko (n.v.budko@tudelft.nl) Problem) by the Fytagoras B.V. (Leiden): "Seed germination in most seeds depends on the availability of oxygen. Living seeds commences. The availability of oxygen to the embryo in the seed depends on the oxygen concentration around

Vuik, Kees

123

Seed aging, delayed germination and reduced competitive ability in Bromus tectorum  

E-print Network

Seed aging, delayed germination and reduced competitive ability in Bromus tectorum Kevin J. Rice1, Competition, Delayed germination, Dormancy, Seed bank Abstract In annual plants, increased competitive species exhibit some degree of delayed germination (i.e., seed dormancy) that results in the formation

Rice, Kevin

124

Genome-wide network model capturing seed germination reveals coordinated regulation  

E-print Network

Genome-wide network model capturing seed germination reveals coordinated regulation of plant 11, 2011 (received for review January 20, 2011) Seed germination is a complex trait of key ecological- cluding two state-dependent sets of interactions associated with dormancy or germination. Seed

Toronto, University of

125

Expression of 9-cis-EPOXYCAROTENOID DIOXYGENASE4 Is Essential for Thermoinhibition of Lettuce Seed Germination  

E-print Network

Germination but Not for Seed Development or Stress ToleranceC W Heqiang Huo,a Peetambar Dahal,a Keshavulu, California 95618 Thermoinhibition, or failure of seeds to germinate at warm temperatures, is common to elevated temperature. INTRODUCTION Seed dormancy and germination are critical phenomena in plant life

Bradford, Kent

126

Concentration and localization of zinc during seed development and germination in wheat  

E-print Network

Concentration and localization of zinc during seed development and germination in wheat Levent during germination, and (3) develop a rapid visual Zn screening method for seed and flour samples. In all- nantly located in the embryo and aleurone parts of the seeds. After 36 h of germination, the coleoptile

Yanikoglu, Berrin

127

Regulation of Seed Germination in the Close Arabidopsis Relative Lepidium sativum: A Global Tissue-Specific  

E-print Network

Regulation of Seed Germination in the Close Arabidopsis Relative Lepidium sativum: A Global Tissue, China (X.W.) The completion of germination in Lepidium sativum and other endospermic seeds (e degradation is a major control point for endosperm weakening. The seed germination process begins

Leubner, Gerhard

128

Abstract. Increased ethylene evolution accompanies seed germination of many species including Pisum  

E-print Network

Abstract. Increased ethylene evolution accompanies seed germination of many species including Pisum and embryonic axis of germinating pea seeds. An early onset and sequential induction of ACC biosynthesis when radicle emergence was just complete. Treatment of germinating seeds with ethylene alone

Leubner, Gerhard

129

Integration of light and abscisic acid signaling during seed germination and early seedling development  

E-print Network

Integration of light and abscisic acid signaling during seed germination and early seedling, The Netherlands, and approved January 31, 2008 (received for review November 13, 2007) Seed germination (ABA) both regulate seed germination and seedling development, although how light and ABA signals

Deng, Xing-Wang

130

Expression of an Expansin Is Associated with Endosperm Weakening during Tomato Seed Germination1  

E-print Network

Expression of an Expansin Is Associated with Endosperm Weakening during Tomato Seed Germination1. In gibberellin (GA)-deficient (gib-1) mutant seeds, which germinate only in the presence of exogenous GA, GA seed germination parallels endosperm cap weakening determined by puncture force analysis. We

Bradford, Kent

131

Beyond gibberellins and abscisic acid: how ethylene and jasmonates control seed germination  

E-print Network

REVIEW Beyond gibberellins and abscisic acid: how ethylene and jasmonates control seed germination germination and acts as an antagonist of ABA. Far less is known about jasmonates in seeds for which we conclusions on the mode of jasmonate action during seed germination. Understanding the mechanisms underlying

Leubner, Gerhard

132

Effect of seed passage through vertebrate frugivores' guts on germination: a review  

Microsoft Academic Search

The capacity of seeds to germinate after ingestion by frugivores is important for the population dynamics of some plant species and significant for the evolution of plant-frugivore interactions. In this paper the effects of different vertebrates on seed germination of nearly 200 plant species are reviewed, searching for patterns that predict the circumstances in which germination of seeds is enhanced,

Anna Traveset

1998-01-01

133

Seasonal pattern of germination and seed longevity in the invasive species Heracleum mantegazzianum  

E-print Network

Seasonal pattern of germination and seed longevity in the invasive species Heracleum mantegazzianum., Pysek P., Pergl J., Perglová I. & Jarosík V. (2006): Seasonal pattern of germination and seed longevity temperature regimes and dry storage on germination of H. mantegazzianum (Apiaceae, native to Caucasus) seeds

Kratochvíl, Lukas

134

Passage through bird guts causes interspecific differences in seed germination characteristics  

Microsoft Academic Search

Summary 1. Seed germination characteristics are often modified after seeds are ingested by frugivores. Factors that are intrinsic either to the plant or to the frugivore's digestive tract are responsible for the great variation observed in germination response. 2. Our objectives were to determine whether and how the seed germination patterns of five common western Mediterranean plant species are affected

A. Traveset; N. Riera; R. E. Mas

2001-01-01

135

Mycoheterotrophic germination of Pyrola asarifolia dust seeds reveals convergences with germination in orchids.  

PubMed

Dust seeds that germinate by obtaining nutrients from symbiotic fungi have evolved independently in orchids and 11 other plant lineages. The fungi involved in this 'mycoheterotrophic' germination have been identified in some orchids and non-photosynthetic Ericaceae, and proved identical to mycorrhizal fungi of adult plants. We investigated a third lineage, the Pyroleae, chlorophyllous Ericaceae species whose partial mycoheterotrophy at adulthood has recently attracted much attention. We observed experimental Pyrola asarifolia germination at four Japanese sites and investigated the germination pattern and symbiotic fungi, which we compared to mycorrhizal fungi of adult plants. Adult P. asarifolia, like other Pyroleae, associated with diverse fungal species that were a subset of those mycorrhizal on surrounding trees. Conversely, seedlings specifically associated with a lineage of Sebacinales clade B (endophytic Basidiomycetes) revealed an intriguing evolutionary convergence with orchids, some of which also germinate with Sebacinales clade B. Congruently, seedlings clustered spatially together, but not with adults. This unexpected transition in specificity and ecology of partners could support the developmental transition from full to partial mycoheterotrophy, but probably challenges survival and distribution during development. We discuss the physiological and ecological traits that predisposed to the repeated recruitment of Sebacinales clade B for dust seed germination. PMID:22642263

Hashimoto, Yasushi; Fukukawa, Satoru; Kunishi, Ayako; Suga, Haruhisa; Richard, Franck; Sauve, Mathieu; Selosse, Marc-André

2012-08-01

136

Biphasic Fluence Response Curves for Induction of Seed Germination 1  

PubMed Central

Fluence-response curves for the induction of seed germination after 24 hours pretreatment at 35°C of Rumex obtusifolius and Arabidopsis thaliana show two phases of response: (a) a very low fluence-response (10?4 - 10?1 micromoles per square meter) and (b) a low fluence-response (1 - 103 micromoles per square meter). PMID:16664390

Kendrick, Richard E.; Cone, John W.

1985-01-01

137

Biphasic fluence response curves for induction of seed germination.  

PubMed

Fluence-response curves for the induction of seed germination after 24 hours pretreatment at 35 degrees C of Rumex obtusifolius and Arabidopsis thaliana show two phases of response: (a) a very low fluence-response (10(-4) - 10(-1) micromoles per square meter) and (b) a low fluence-response (1 - 10(3) micromoles per square meter). PMID:16664390

Kendrick, R E; Cone, J W

1985-09-01

138

Sulfur dioxide effects on petunia pollen germination and seed set  

SciTech Connect

Information pertaining to SO/sub 2/ effects on sexual reproduction is extremely limited even though this complex process is critical especially in annual species. This study reports the SO/sub 2/ effect on both in vitro and in vivo pollen germination characteristics and in vivo seed set in Petunia hybrida Vilm.

Linskens, H.F.; van Megen, Y.; Pfahler, P.L.; Wilcox, M.

1985-05-01

139

A microcalorimetric study of Chenopodium quinoa Willd. seed germination  

Microsoft Academic Search

Quinoa (Chenopodium quinoa Willd.) is an ancestral crop from the Andes of South America. Due to its high nutritional value, several countries started to promote research to develop quinoa as a new crop. One of quinoa problems is the poor germinability of their seeds.In this investigation, isothermal microcalorimetry is used as a monitor of two cultivars (cv. Robura and cv.

E. Elizabeth Sigstad; Fernando E Prado

1999-01-01

140

Chaparral & Fire Ecology: Role of Fire in Seed Germination.  

ERIC Educational Resources Information Center

An activity that incorporates the concepts of plant structure and function and ecology is described. Students investigate the reasons why some California chaparral seeds germinate only after a fire has burned the surrounding chaparral. The procedure, discussion and analysis questions, expected results, potential problems, and additional activities…

Steele, Nancy L. C.; Keeley, Jon E.

1991-01-01

141

Inhibitory effects of monoterpenes on seed germination and seedling growth.  

PubMed

Monoterpenes, the chemical constituents of essential oils found in plants, are known biologically active compounds. The present study was conducted to investigate the inhibitory effects of 30 monoterpenes including monoterpene hydrocarbons and oxygenated monoterpenes on seed germination and seedling growth of Amaranthus retroflexus, Chenopodium album and Rumex crispus under laboratory conditions. The monoterpenes were applied at contents of 10 and 20 microl for liquid compounds and 10 and 20 microg for solid compounds. The results show that most of the monoterpenes significantly inhibited seed germination and seedling growth of the tested plants. Oxygenated monoterpenes including beta-citronellol, nerol and terpinen-4-ol completely inhibited seed germination and seedling growth of all tested plants. Their inhibitory effects were also stronger than that of the herbicide 2,4-D. In general, monoterpenes were less effective against seed germination and seedling growth of C. album as compared with R. crispus and A. retroflexus. Phytotoxic effects of monoterpene hydrocarbons were found to be lower than those of oxygenated monoterpenes. The alcohol derivatives of oxygenated monoterpenes were also found to be more phytotoxic as compared with their acetate derivatives. Based on the present results, it can be concluded that the oxygenated monoterpenes can be used as potential bio-herbicides. PMID:17542486

Kordali, Saban; Cakir, Ahmet; Sutay, Sunay

2007-01-01

142

Response of soybean seed germination to cadmium and acid rain.  

PubMed

Cadmium (Cd) pollution and acid rain are the main environmental issues, and they often occur in the same agricultural region. Nevertheless, up to now, little information on the combined pollution of Cd(2+) and acid rain action on crops were presented. Here, we investigated the combined effect of Cd(2+) and acid rain on the seed germination of soybean. The results indicated that the single treatment with the low level of Cd(2+) (0.18, 1.0, 3.0 mg L(-1)) or acid rain (pH ?3.0) could not affect the seed germination of soybean, which was resulted in the increased activities of peroxidase and catalase. The single treatment with the high concentration of Cd(2+) (>6 mg L(-1)) or acid rain at pH 2.5 decreased the activities of peroxidase and catalase, damaged the cell membrane and then decreased the seed germination of soybean. Meanwhile, the same toxic effect was observed in the combined treatment with Cd(2+) and acid rain, and the combined treatment had more toxic effect than the single treatment with Cd(2+) or acid rain. Thus, the combined pollution of Cd(2+) and acid rain had more potential threat to the seed germination of soybean than the single pollution of Cd(2+) or acid rain. PMID:21479540

Liu, Ting Ting; Wu, Peng; Wang, Li Hong; Zhou, Qing

2011-12-01

143

Germination of vegetable seeds exposed to very high pressure  

NASA Astrophysics Data System (ADS)

Effects of high hydrostatic pressure were investigated on vegetable seeds in the GPa range to examine the potentialities of breed improvement by high-pressure processing. Specimens of several seeds of broccoli (Brassica oleracea var. italica), Turnip leaf (Brassica rapa var. perviridis) and Potherb Mustard (Brassica rapa var. nipposinica) were put in a teflon capsule with liquid high pressure medium, fluorinate, and inserted into a pyrophillite cube. By using a cubic anvil press a hydrostatic pressure of 5.5 GP a was applied to these seeds for 15 minutes. After being brought back to ambient pressure, they were seeded on humid soil in a plant pot. Many of these vegetable seeds began to germinate within 6 days after seeded.

Mori, Y.; Yokota, S.; Ono, F.

2012-07-01

144

Modeling the Effect of Density-Dependent Chemical Interference upon Seed Germination  

PubMed Central

A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:18648596

Sinkkonen, Aki

2006-01-01

145

Modeling the Effect of Density-Dependent Chemical Interference Upon Seed Germination  

PubMed Central

A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:19330163

Sinkkonen, Aki

2005-01-01

146

Life cycle inventory for the production of germinated oil palm seeds at a selected seed production unit in Malaysia  

NASA Astrophysics Data System (ADS)

The increasing global demand for edible oil has encouraged Malaysia to increase the areas under oil palm cultivation. The total demand for germinated oil palm seeds in the years 2009, 2010, 2011 and 2012 were 86.4, 76.5, 72.6 and 75.2 million, respectively. Production of germinated oil palm seeds is the first link in the palm oil supply chain. Therefore, good management practices at seed production stage is required to ensure only high quality germinated oil palm seeds are produced before sale to customers. Life cycle assessment (LCA) has been used as a tool to assess environmental impact of the processes throughout a product's lifespan and this approach is an important tool for assessing green house gas (GHG) emission. For this study, a gate-to-gate life cycle inventory (LCI) of a single germinated oil palm seed production unit was carried out. The functional unit used for this LCI was one germinated oil palm seed. To determine the environmental impact for the production of germinated oil palm seeds, information on the inputs were obtained. The inputs for the production of germinated oil palm seeds involved materials such as polyethylene bags, electricity, water, chemicals and fungicides. For this study, the system boundary involved seed germination process and management of germinated oil palm seeds. It was found that the amount of input such as materials and energy used in the production of germinated oil palm seeds was very minimal.

Khairuddin, Nik Sasha Khatrina; Ismail, B. S.; Muhamad, Halimah; May, Choo Yuen

2013-11-01

147

Mapping quantitative trait loci for salt tolerance at germination and the seedling stage in barley (Hordeum vulgare L.)  

Microsoft Academic Search

Quantitative trait loci (QTLs) controlling salt tolerance at germination and the seedling stage in barley (Hordeum vulgare\\u000a L.) were identified by interval mapping analysis using marker information from two doubled haploid (DH) populations derived\\u000a from the crosses, Steptoe\\/Morex and Harrington\\/TR306.\\u000a \\u000a Interval mapping analysis revealed that the QTLs for salt tolerance at germination in the DH lines of Steptoe\\/Morex were located

Yoshiro Mano; Kazuyoshi Takeda

1997-01-01

148

Methods toward improving 'Grande Rio 66' pepper seed germination  

E-print Network

1ous transplant methods, and the third experiment attempts to determ1ne a po1nt in which pepper seed germinat1on begins to decline during storage. The citations in this thesis follow the form of the Journal of the American ~Societ... for Horticultural Science. LITERATURE REVIEW Seed and Fruit S1ze Thompson and Fox (45) stated that the qualities whfch may result in uneven germination arise from polymorph1sms fn seed samples due to var1ed genotypic or phenotypic responses of 1nd1viduals. Th1s...

Rogers, Barbara Anna

2012-06-07

149

Methods to Promote Germination of Dormant Setaria viridis Seeds  

PubMed Central

Setaria viridis has recently emerged as a promising genetic model system to study diverse aspects of monocot biology. While the post-germination life cycle of S. viridis is approximately 8 weeks long, the prolonged dormancy of freshly harvested seeds can more than double the total time required between successive generations. Here we describe methods that promote seed germination in S. viridis. Our results demonstrate that treating S. viridis seeds with liquid smoke or a GA3 and KNO3 solution improves germination rates to 90% or higher even in seeds that are 6 days post-harvest with similar results obtained whether seeds are planted in soil or on gel-based media. Importantly, we show that these treatments have no significant effect on the growth of the adult plant. We have tested these treatments on diverse S. viridis accessions and show variation in their response. The methods described here will help advance research using this model grass species by increasing the pace at which successive generations of plants can be analyzed. PMID:24748008

Sebastian, Jose; Wong, Mandy Ka; Tang, Evan; Dinneny, José R.

2014-01-01

150

Interactions of light and a temperature shift on seed germination.  

PubMed

Germination of Rumex obtusifolius L. seeds is potentiated to an observable degree in 2 minutes by a single shift in temperature from 20 to 35 C. Half-maximal potentiation requires less than 32 minutes at the higher temperature. Similar sensitivities to shifts in temperature were observed for seeds of Barbarea vulgaris, R.Br. B. verna (Mill.) Asch., and Lepidium virginicum L. A shift in temperature interacts strongly with change in form of phytochrome induced by light on germination of the four kinds of seeds. The potentiated effects for R. obtusifolius are only moderately affected by 40 mum cycloheximide. Both the temperature shift and light actions are apparently independent of processes of synthesis necessary for growth. PMID:16657910

Taylorson, R B; Hendricks, S B

1972-02-01

151

Interactions of Light and a Temperature Shift on Seed Germination  

PubMed Central

Germination of Rumex obtusifolius L. seeds is potentiated to an observable degree in 2 minutes by a single shift in temperature from 20 to 35 C. Half-maximal potentiation requires less than 32 minutes at the higher temperature. Similar sensitivities to shifts in temperature were observed for seeds of Barbarea vulgaris, R.Br. B. verna (Mill.) Asch., and Lepidium virginicum L. A shift in temperature interacts strongly with change in form of phytochrome induced by light on germination of the four kinds of seeds. The potentiated effects for R. obtusifolius are only moderately affected by 40 ?m cycloheximide. Both the temperature shift and light actions are apparently independent of processes of synthesis necessary for growth. PMID:16657910

Taylorson, R. B.; Hendricks, S. B.

1972-01-01

152

A simulation model for seasonal changes in dormancy and germination of weed seeds  

Microsoft Academic Search

A model has been developed to simulate the annual dormancy cycle of seeds of light-requiring species in the seed bank and the germination of exhumed seeds after irradiation. Simulation of dormancy and germination is based on a physiological model concerning the action of phytochrome in the seed. Dormancy is related to the amount of a hypothetical phytochrome receptor, which fluctuates

L. M. Vleeshouwers; H. J. Bouwmeester

2001-01-01

153

Photoinhibition of germination in grass seed--implications for prairie revegetation.  

PubMed

Germination photoinhibition is not a recognized cause of revegetation failure; yet prolonged sunlight exposure can inhibit germination of several grass species. This research addressed susceptibility to photoinhibition of selected native grass species used to restore Canadian prairies, and reclamation treatments to alter environmental conditions in order to release seeds from photoinhibition. Under laboratory conditions effects of photoinhibition were tested on the ability of seeds to germinate at low water potential and effects of daily alternating temperatures and nitrates to break photoinhibition. Whether surficial mulch can release seeds from photoinhibition was assessed in a field experiment. Germination photoinhibition was evident in Festuca hallii and Koeleria macrantha seeds even under very low irradiances. The prolonged exposure to light decreased germination rates and ability of seeds to germinate at low water potentials. Daily fluctuating temperatures released a fraction of Bromus carinatus and Elymus trachycaulus seeds from photoinhibition yet did not improve F. hallii or K. macrantha germinability. Nitrates failed to break seed photoinhibition in all species tested. In the field experiment, mulched F. hallii seeds (covered with an erosion control blanket) showed a tenfold increase in germination percentages relative to seeds exposed to direct sunlight, indicating the facilitative effects of mulching on attenuation of the light environment. We conclude that germination photoinhibition as a cause of emergence failures in land reclamation where seed is broadcast or shallow seeded should be recognized and germination photoinhibition included in the decision making process to select revegetation seeding techniques. PMID:24794519

Mollard, Federico P O; Naeth, M Anne

2014-09-01

154

Seed germination and life history syndromes in the California chaparral  

USGS Publications Warehouse

Syndromes are life history responses that are correlated to environmental regimes and are shared by a group of species (Stebbins, 1974). In the California chaparral there are two syndromes contrasted by the timing of seedling recruitment relative to wildfires. One syndrome, here called the fire-recruiter or refractory seed syndrome, includes species (both resprouting and non-resprouting) which share the feature that the timing of seedling establishment is specialized to the first rainy season after fire. Included are woody, suffrutescent and annual life forms but no geophytes have this syndrome. These species are linked by the characteristic that their seeds have a dormancy which is readily broken by environmental stimuli such as intense heat shock or chemicals leached from charred wood. Such seeds are referred to as “refractory” and dormancy, in some cases, is due to seed coat impermeability (such seeds are commonly called hardseeded), but in other cases the mechanism is unknown. Seeds of some may require cold stratification and/or light in addition to fire related stimuli. In the absence of fire related cues, a portion or all of a species’ seed pool remains dormant. Most have locally dispersed seeds that persist in the soil seed bank until the site burns. Dispersal of propagules is largely during spring and summer which facilitates the avoidance of flowering and fruiting during the summer and fall drought. Within a life form (e.g., shrub, suffrutescent, etc.), the seeds of these species have less mass than those of species with non-refractory seeds and this possibly reflects the environmental favorableness of the postfire environment for seedling establishment. Regardless of when fire occurs, germination is normally delayed until late winter or early spring. In the absence of fire, or other disturbance, opportunities for population expansion are largely lacking for species with this syndrome. The other syndrome, here called the fire-resister or non-refractory seed syndrome, includes species that are resilient to frequent fires (mostly by vegetative resprouting), but require fire-free periods for recruiting new seedlings. Included are shrubs, subshrubs, suffrutescents, lianas, geophytes and annuals. All are linked by the characteristic that their seeds germinate in the absence of cues related to wildfires. In many cases no form of seed dormancy is present and the seeds germinate soon after dispersal; consequently these species do not accumulate a persistent seed bank. Germination and seedling establishment is independent of fire and thus opportunities for population expansion are also independent of fire. The demographic pattern of seedling recruitment varies with the life form. For shrubs, seedling recruitment may be restricted to sites free of fire for periods of a hundred years or more. Recruitment appears to require relatively mesic conditions and this may account for the patchy distribution of these species within the matrix of relatively arid sites. Finding such sites has selected for propagules specialized for wind or animal dispersal; the majority are bird dispersed. These shrub species all disperse fruits in fall and winter and this may have been selected to take advantage of migratory birds as well as to time dispersal to the winter rains typical of the mediterranean-climate. Germination typically occurs within several weeks of the first fall or winter rains. Maturation of flowers and fruits during the summer and fall drought may account for the distribution of these species on more mesic sites. Seed mass of these species is large and this may have been selected to provide an advantage to seedlings establishing under the canopy of this dense shrub community.

Keeley, J.E.

1991-01-01

155

Diversification of phytochrome contributions to germination as a function of seed-maturation environment.  

PubMed

Environmental conditions during seed maturation influence germination, but the genetic basis of maternal environmental effects on germination is virtually unknown. Using single and multiple mutants of phytochromes, it is shown here that different phytochromes contributed to germination differently, depending on seed-maturation conditions. Arabidopsis thaliana wild-type seeds that were matured under cool temperatures were intensely dormant compared with seeds matured at warmer temperature, and this dormancy was broken only after warm seed-stratification followed by cold seed-stratification. The warm-cold stratification broke dormancy in fresh seeds but not in dry after-ripened seeds. Functional PHYB and PHYD were necessary to break cool-induced dormancy, which indicates a previously unknown and ecologically important function for PHYD. Disruption of PHYA in combination with PHYD (but not PHYB) restored germination to near wild-type levels, indicating that PHYA contributes to the maintenance of cool-induced dormancy on a phyD background. Effects of seed-maturation temperature were much stronger than effects of seed-maturation photoperiod. PHYB contributed to germination somewhat more strongly in seeds matured under short days, whereas PHYD contributed to germination somewhat more strongly in seeds matured under long days. The variable contributions of different phytochromes to germination as a function of seed-maturation conditions reveal further functional diversification of the phytochromes during the process of germination. This study identifies among the first genes to be associated with maternal environmental effects on germination. PMID:18028293

Donohue, Kathleen; Heschel, M Shane; Butler, Colleen M; Barua, Deepak; Sharrock, Robert A; Whitelam, Garry C; Chiang, George C K

2008-01-01

156

Reduced seed germination in Arabidopsis over-expressing SWI/SNF2 ATPase genes.  

PubMed

In the life of flowering plants, seed germination is a critical step to ensure survival into the next generation. Generally the seed prior to germination has been in a dormant state with a low rate of metabolism. In the transition from a dormant seed to a germinating seed, various epigenetic mechanisms play a regulatory role. Here, we demonstrate that the over-expression of chromatin remodeling ATPase genes (AtCHR12 or AtCHR23) reduced the frequency of seed germination in Arabidopsis thaliana up to 30% relative to the wild-type seeds. On the other hand, single loss-of-function mutations of the two genes did not affect seed germination. The reduction of germination in over-expressing mutants was more pronounced in stress conditions (salt or high temperature), showing the impact of the environment. Reduced germinations upon over-expression coincided with increased transcript levels of seed maturation genes and with reduced degradation of their mRNAs stored in dry seeds. Our results indicate that repression of AtCHR12/23 gene expression in germinating wild-type Arabidopsis seeds is required for full germination. This establishes a functional link between chromatin modifiers and regulatory networks towards seed maturation and germination. PMID:24839909

Leeggangers, Hendrika A C F; Folta, Adam; Muras, Aleksandra; Nap, Jan-Peter; Mlynarova, Ludmila

2015-02-01

157

Optimum Storage and Germination Conditions for Seeds of Pickerelweed (Pontederia cordata L.) from Florida  

Microsoft Academic Search

Clean seeds of pickerelweed (Pontederia cordata L. [Pontederiaceae]) germinated best (84 to 94%) under water, even after being stored dry up to 6 mo at about 25 °C (77 °F), but germination of clean seeds under water was reduced to 43% when seeds were stored at 4 °C (39 °F) for 6 mo. Underwater germination of seeds enclosed in fruits

Lyn A Gettys; R Kasten Dumroese

2009-01-01

158

Effects of livestock on seed germination of guava ( Psidium guajava L.)  

Microsoft Academic Search

This paper reports on the effects that livestock have on seed germination of guava (Psidium guajava L.). Experiments here reported were intended to simulate gastric scarification using different soaking periods in a 0.01 N HCl solution alone or combined with rumen treatments. Additional experiments evaluated germination of defecated and nondefecated seeds germinated in petri dishes and in cow dung.

Eduardo Somarriba

1986-01-01

159

Distinct expression patterns of -1,3-glucanases and chitinases during the germination of Solanaceous seeds  

E-print Network

Distinct expression patterns of -1,3-glucanases and chitinases during the germination patterns of -1,3-glucanases ( Glu) and chitinases (Chn) were investigated during the seed germination, gibberellin, -1,3-glucanase, Nicotiana, seed germination, Solanaceae family Introduction The intrafamilial

Leubner, Gerhard

160

Seed Germination of Triglochin Maritima as Influenced by Salinity and Dormancy Relieving Compounds  

Microsoft Academic Search

Triglochin maritima had only 40 % germination in distilled water, but germination was substantially enhanced when seeds were exposed to ethephon, fusicoccin, proline, kinetin, and thiourea. Also, the effect of low salinity on germination was alleviated by fusicoccin, kinetin, nitrate and thiourea, whereas, the reduction in germination at high salinity was partially countered by ethephon, kinetin, thiourea and nitrate.

M. A. Khan; I. A. Ungar

2001-01-01

161

The development of isocitric lyase activity in germinating cotton seed.  

PubMed

In cotyledons of germinating cotton (Gossypium hirsutum L. var. Stoneville 213) seedlings, in the dark, isocitric lyase (EC 4.1.3.1) activity peaks after 2 days and thereafter slowly declines to a negligible value after 8 days. The maximum activity of this enzyme in cotyledons of 2-day-old seedlings was 16.2 mumoles of glyoxylate formed/15 min.10 cotyledon pairs. Actinomycin D at a concentration of 10 mug/ml, if added to the imbibing solution, completely prevents the development of isocitric lyase activity in these germinating seed. In cotyledons of germinating cotton seedlings, in the light, isocitric lyase activity peaks after 2 to 3 days and sharply declines to a negligible value after 4 days. The maximum activity of this enzyme in cotyledons of 2- to 3-day-old seedlings was 13.2 mumoles of glyoxylate formed/15 min.10 cotyledon pairs. Actinomycin D at a concentration of 10 mug/ml, if added to the imbibing solution, severely inhibits the development of enzyme activity.In germinating seed, in the light, the synthesis of chlorophyll and glyceraldehyde-3-P dehydrogenase is also limited by the addition of low concentrations of actinomycin D. The new synthesis of fructose-1, 6-diP aldolase, which is detectable after 1 to 2 days of germination, is inhibited by 10 mug/ml of actinomycin D. We, therefore, conclude that the synthetic events leading to the development of chlorophyll, some glyoxysomal and chloroplast enzymes in germinating cotton seedlings depend on newly transcribed mRNA. PMID:16658859

Smith, R H; Schubert, A M; Benedict, C R

1974-08-01

162

The role of mallard ducks ( Anas platyrhynchos ) in distribution and germination of seeds of the submerged hydrophyte Najas marina L  

Microsoft Academic Search

Summary The effect of passage ofNajas marina L. seeds through the digestive system of the common mallard duck (Anas platyrhynchos) on their germinability was investigated. Most of the seeds (~70%), which were consumed by the birds were digested. However, germination of the remaining seeds was remarkably improved. Germination of seeds whose seed coats were mechanically cracked was also higher than

Moshe Agami; Yoav Waisel

1986-01-01

163

7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.  

...2014-01-01 2014-01-01 false Germination of vegetable seed in containers of more than 1 pound...ACT REGULATIONS Labeling Vegetable Seeds § 201.29a Germination of vegetable seed in containers of more than 1...

2014-01-01

164

7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 2011-01-01 false Germination of vegetable seed in containers of more than 1 pound...ACT REGULATIONS Labeling Vegetable Seeds § 201.29a Germination of vegetable seed in containers of more than 1...

2011-01-01

165

7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.  

Code of Federal Regulations, 2012 CFR

...2012-01-01 2012-01-01 false Germination of vegetable seed in containers of more than 1 pound...ACT REGULATIONS Labeling Vegetable Seeds § 201.29a Germination of vegetable seed in containers of more than 1...

2012-01-01

166

7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.  

Code of Federal Regulations, 2013 CFR

...2013-01-01 2013-01-01 false Germination of vegetable seed in containers of more than 1 pound...ACT REGULATIONS Labeling Vegetable Seeds § 201.29a Germination of vegetable seed in containers of more than 1...

2013-01-01

167

Response of Soybean Seed Germination to Cadmium and Acid Rain  

Microsoft Academic Search

Cadmium (Cd) pollution and acid rain are the main environmental issues, and they often occur in the same agricultural region.\\u000a Nevertheless, up to now, little information on the combined pollution of Cd2+ and acid rain action on crops were presented. Here, we investigated the combined effect of Cd2+ and acid rain on the seed germination of soybean. The results indicated

Ting Ting Liu; Peng Wu; Li Hong Wang; Qing Zhou

168

Osmoconditioning and storage of native Texas wildflower seed to improve the rate and uniformity of germination  

E-print Network

AS AFFECTED BY OSMOCONDITIONING AND STORAGE 52 V. THE EFFECTS OF PRIMING ON GAILLARDIA PULCHELLA AND GAILLARDIA ARISTATA LABORATORY GERMINATION AND GREENHOUSE EMERGENCE 71 VI. THE GERMINATION RESPONSE OF FOUR SPECIES OF PRIMED WILDFLOWER SEEDS 90...

Samfield, Dina Margaret

2012-06-07

169

Germination of native grasses The fall burn consumed all the litter and left bare soil in which seeded  

E-print Network

seeded grass germinated. Cool wet weather followed the fall burn. Spring conditions were too wet to burn evenly, but the season dried out too quickly for germination to occur. A. Fall burn plot with seeded grass germination B. Control plot without seeded grass germination BA INTRODUCTION Brush mastication has

Muir, Patricia

170

Effects of fruit position on fruit mass and seed germination in the alien species Heracleum mantegazzianum (Apiaceae)  

E-print Network

Effects of fruit position on fruit mass and seed germination in the alien species Heracleum of position of fruit on a plant affects the germination characteristics of seed of Heracleum mantegazzianum diameter) were recorded. Percentage germination and germination rate (time to when 50% of the seeds had

Kratochvíl, Lukas

171

Seasonal cycles in the germination capacity of buried seeds of some Leguminosae (Fabaceae)  

Microsoft Academic Search

Summary • The influence of seasonal factors on the germination of impermeable seeds of Fabaceae was studied. Seeds of 14 herbaceous species were buried for up to 2.5 yr and exposed to natural seasons. At regular intervals, seeds were exhumed and ger- mination was tested in four different temperature regimes. Some species had a very low percentage germination regardless of

Jozef A. Van Assche; Katrien L. A. Debucquoy; Wouter A. F. Rommens

2003-01-01

172

Ecology of seed dormancy and germination of Carex divisa Huds.: Effects of stratification, temperature and salinity  

Microsoft Academic Search

Carex divisa is a patrimonial rhizomatous species and acts as an important component of grazed wet permanent grassland on the French Atlantic coast. This study treated three storage regimes (wet- cold, dry-cold and dry-warm), burial in soil, fluctuating temperature and salinity on seed germination of C. divisa. The seeds were dormant at maturity. No seed germinated after 2 and 6

M. Mohammad; A. Sattarian; A. Bonis; J. B. Bouzilléb

173

Temperature-dependent models of Zannichellia palustris seed germination for application in aquatic systems  

Technology Transfer Automated Retrieval System (TEKTRAN)

The germination characteristics of Zannichellia palustris seeds collected from the spring-fed Fall River of Northern California were investigated across a range of constant temperatures from 4.2 to 40.8 ºC. Germination experiments were conducted on freshly produced and collected seeds. Seeds germina...

174

Interaction of accelerated aging and p-coumaric acid on crimson clover seed germination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several phenolic acids, including p-coumaric acid, have been described as allelochemicals that may inhibit seed germination or seedling growth. Accelerated seed aging (high temperature (41 C) and high humidity (100%)) reduces germination and seedling vigor, and provides some indication as to seed g...

175

Proteomic analysis of seed germination under salt stress in soybeans*  

PubMed Central

Soybean (Glycine max (L.) Merrill) is a salt-sensitive crop, and its production is severely affected by saline soils. Therefore, the response of soybean seeds to salt stress during germination was investigated at both physiological and proteomic levels. The salt-tolerant cultivar Lee68 and salt-sensitive cultivar N2899 were exposed to 100 mmol/L NaCl until radicle protrusion from the seed coat. In both cultivars, the final germination percentage was not affected by salt, but the mean germination times of Lee68 and N2899 were delayed by 0.3 and 1.0 d, respectively, compared with controls. In response to salt stress, the abscisic acid content increased, and gibberellic acid (GA1+3) and isopentenyladenosine decreased. Indole-3-acetic acid increased in Lee68, but remained unchanged in N2899. The proteins extracted from germinated seeds were separated using two-dimensional gel electrophoresis (2-DE), followed by Coomassie brilliant blue G-250 staining. About 350 protein spots from 2-DE gels of pH range 3 to 10 and 650 spots from gels of pH range 4 to 7 were reproducibly resolved, of which 18 protein spots showed changes in abundance as a result of salt stress in both cultivars. After matrix-assisted laser desorption ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) analysis of the differentially expressed proteins, the peptide mass fingerprint was searched against the soybean UniGene database and nine proteins were successfully identified. Ferritin and 20S proteasome subunit ?-6 were up-regulated in both cultivars. Glyceraldehyde 3-phosphate dehydrogenase, glutathione S-transferase (GST) 9, GST 10, and seed maturation protein PM36 were down-regulated in Lee68 by salt, but still remained at a certain level. However, these proteins were present in lower levels in control N2899 and were up-regulated under salt stress. The results indicate that these proteins might have important roles in defense mechanisms against salt stress during soybean seed germination. PMID:21726057

Xu, Xiao-yan; Fan, Rui; Zheng, Rui; Li, Chun-mei; Yu, De-yue

2011-01-01

176

Internal dispersal of seeds by waterfowl: effect of seed size on gut passage time and germination patterns  

NASA Astrophysics Data System (ADS)

Long distance dispersal may have important consequences for gene flow and community structure. The dispersal of many plants depends on transport by vertebrate seed dispersers. The shapes of seed shadows produced by vertebrates depend both on movement patterns of the dispersers and on the dynamics and effects of passage through the disperser’s gut (i.e. the retention time, survival and germination of ingested seeds). A combination of experiments with captive waterbirds and aquatic plant seeds was used to analyse the following: (a) the effects of inter- and intra-specific variation in seed size and duck species on seed retention time in the gut and (b) the relationship between retention time and the percent germination and germination rates of seeds. Among the three Scirpus species used, those with smaller seeds showed higher survival after ingestion by birds and longer retention times inside their guts than those with larger seeds. For Potamogeton pectinatus, only seeds from the smaller size class (<8 mg) survived ingestion. Retention time affected the percent germination and germination rate of Scirpus seeds but in a manner that varied for the different plant and bird species studied. We recorded both linear and non-linear effects of retention time on percent germination. In addition, germination rate was positively correlated with retention time in Scirpus litoralis but negatively correlated in Scirpus lacustris. Small seed size can favour dispersal over larger distances. However, the effects of retention time on percent germination can modify the seed shadows produced by birds due to higher percent germination of seeds retained for short or intermediate periods. The changes in dispersal quality associated with dispersal distance (which is expected to be positively related to retention time) will affect the probability of seedling establishment over longer distances and, thus, the spatial characteristics of the effective seed shadow.

Figuerola, Jordi; Charalambidou, Iris; Santamaria, Luis; Green, Andy J.

2010-06-01

177

SEED PHOSPHORUS AND INOSITOL PHOSPHATE PHENOTYPE OF BARLEY LOW PHYTIC ACID GENOTYPES  

Technology Transfer Automated Retrieval System (TEKTRAN)

myo-Inositol-1,2,3,4,5,6-hexakisphosphate (Ins P6 or "phytic acid") typically represents ~75% of the total phosphorus and >80% of soluble myo-inositol (Ins) phosphates in seeds. The seed phosphorus and Ins phosphate phenotypes of four non-lethal barley (Hordeum vulgare L.) low phytic acid mutations...

178

Effect of salinity and chemical factors on seed germination in the halophyte Crithmum maritimum L  

Microsoft Academic Search

Seeds of the halophyte Crithmum maritimum L. were exposed to salt stress and chemical pretreatments in order to improve germination. Seeds submitted to salt stress\\u000a did not germinate but they recovered rapidly upon transfer to distilled water, recovery being higher after a low salinity\\u000a pretreatment. Chemical treatments resulted in differential effects on seed germination. Known dormancy breakers such as potassium

Laetitia Meot-Duros; Christian Magné

2008-01-01

179

Dormancy patterns, germination ecology, and seed-bank types of twenty temperate fen grassland species  

Microsoft Academic Search

The germination ecology, including primary and secondary dormancy, mortality of seeds, and seed-bank type, of 20 fen grassland\\u000a species from Northern Germany was investigated using a combination of burial and germination experiments. To analyze primary\\u000a dormancy and effects of after-ripening (dry storage for 28 days) on freshly matured seeds, germination was measured at two\\u000a fluctuating temperature regimes (15\\/25°C and 5\\/15°C)

Kai Jensen

2004-01-01

180

Comparison of germination and seed bank dynamics of dimorphic seeds of the cold desert halophyte Suaeda corniculata subsp. mongolica  

PubMed Central

Background and Aims Differences in dormancy and germination requirements have been documented in heteromorphic seeds of many species, but it is unknown how this difference contributes to maintenance and regeneration of populations. The primary aim of this study was to compare the seed bank dynamics, including dormancy cycling, of the two seed morphs (black and brown) of the cold desert halophyte Suaeda corniculata and, if differences were found, to determine their influence on regeneration of the species. Method Seeds of the two seed morphs were buried, exhumed and tested monthly for 24 months over a range of temperatures and salinities, and germination recovery and viability were determined after exposure to salinity and water stress. Seedling emergence and dynamics of the soil seed bank were also investigated for the two morphs. Key Results Black seeds had an annual dormancy/non-dormancy cycle, while brown seeds, which were non-dormant at maturity, remained non-dormant. Black seeds also exhibited an annual cycle in sensitivity of germination to salinity. Seedlings derived from black seeds emerged in July and August and those from brown seeds in May. Seedlings were recruited from 2·6 % of the black seeds and from 2·8 % of the brown seeds in the soil, and only 0·5 % and 0·4 % of the total number of black and brown seeds in the soil, respectively, gave rise to seedlings that survived to produce seeds. Salinity and water stress induced dormancy in black seeds and decreased viability of brown seeds. Brown seeds formed only a transient soil seed bank and black seeds a persistent seed bank. Conclusions The presence of a dormancy cycle in black but not in brown seeds of S. corniculata and differences in germination requirements of the two morphs cause them to differ in their germination dynamics. The study contributes to our limited knowledge of dormancy cycling and seed bank formation in species producing heteromorphic seeds. PMID:22975287

Cao, Dechang; Baskin, Carol C.; Baskin, Jerry M.; Yang, Fan; Huang, Zhenying

2012-01-01

181

Seed dormancy\\/germination traits of seven Persicaria species and their implication in soil seed-bank strategy  

Microsoft Academic Search

In order to predict species-specific potential to form persistent soil seed-banks and to characterize the dynamics of their seed-banks, the seed dormancy\\/germination traits of seven Persicaria ( Polygonum s.lat.) species sharing lakeshore habitats in central Japan were examined. Strict light requirements for seed germination were not observed in any of the species examined. Although all species required moist chilling (0–6

Sachiko Araki; Izumi Washitani

2000-01-01

182

cis-4-Cyclohexene-1,2-dicarboximide: Inhibitor of phytochrome-promoted seed germination  

PubMed Central

cis-4-Cyclohexene-1,2-dicarboximide (CHDC) inhibits the germination of light-requiring seeds in both light and darkness but has no effect upon the germination of non-light-requiring seeds. In lettuce seeds, CHDC inhibits the action of far-red-absorbing form of phytochrome in breaking dormancy. This inhibition can be overcome by benzyladenine and red light together, but not by a combination of red light and gibberellic acid. Gibberellic acid-induced germination of lettuce seeds in darkness is inhibited also by CHDC. Embryos isolated from dark-imbibed lettuce seeds germinate on the inhibitor. CHDC was thought to be an “analogue” of cycloheximide, but it does not inhibit protein synthesis in lettuce seeds. Our results lead us to conclude that CHDC inhibits germination of seeds that require red light to break dormancy and interferes with some aspect of metabolism that is stimulated by far-red-absorbing form of phytochrome. PMID:16592841

Bewley, J. Derek; Oaks, Ann

1980-01-01

183

Hairy vetch (Vicia villosa) seed size affects germination response to coumarin  

Technology Transfer Automated Retrieval System (TEKTRAN)

The inhibition of seed germination by an allelochemical is generally greater in small seeds than in large seeds. This response may have significant impact on weed control by allelopathic cover crops where the small-seeded weeds would be more effectively controlled than large-seeded species. The stu...

184

Variation of hairy vetch seed weight alters germination and seedling growth response to an allelochemical  

Technology Transfer Automated Retrieval System (TEKTRAN)

The inhibition of seed germination by an allelochemical is generally greater in small seeds than in large seeds. This response may have significant impact on weed control by allelopathic cover crops where the small-seeded weeds would be controlled more effectively than large-seeded species. In our...

185

-Helophyte germination in a coastal marsh: gut-passage by ducks changes seed response -315 Question:Inseedswhichareregularlyconsumedbywaterbirds  

E-print Network

- Helophyte germination in a coastal marsh: gut-passage by ducks changes seed response - 315 platyrhynchos). Both the ingested seeds (passage) and non-ingested seeds (controls) were exposed, in germination lineal models. Recovery tests on seeds that did not germinate in the various treatments and tests

Green, Andy J.

186

Cross-species approaches to seed dormancy and germination: conservation and biodiversity of ABA-regulated mechanisms  

E-print Network

Cross-species approaches to seed dormancy and germination: conservation and biodiversity of ABA OF GERMINATION 1), a major quantitative trait gene more specifically involved in seed dormancy, was so far only- dormant seeds was not known. Seed germination of Lepi- dium sativum (`garden cress') is controlled by ABA

Leubner, Gerhard

187

Germination of Styrax camporum Pohl. seeds in response to substrate types, moisture contents and the seed morphology.  

PubMed

This study evaluated the contributions of Styrax camporum seed morphology (size of seeds, presence or absence of endocarp attached to the seed), different substrates (filter paper, vermiculite, sand and the soils of cerrado s. str., cerradão and a riparian forest), different water potentials (0, -0.1, -0.2, -0.3, -0.4 and -0.5 MPa), light and temperature to seed germination. Seed size did not affect the germination percentage when seeds were sown on vermiculite. Seeds were affected by small variations in the moisture content of the tested substrates, showing a significant decrease in germination under water potentials lower than -0.1 MPa, close to the field capacity of cerrado s. str. soils. At the temperatures of 15 and 20°C, a significant decrease in germination was observed. Thus, the availability of water in cerrado soils associated to temperature modulate the distribution of germination in this species. Seed morphology contributes to the maintenance of seeds in the soil, and the lack of synchrony in seed germination spreads the distribution of germination in time. These peculiarities allow the emergency of seedlings at different time periods and establishment conditions, an adaptative response of S. camporum to the cerrado environment. PMID:23460429

Simão, Edson; Nakamura, Adriana T; Takaki, Massanori

2013-03-01

188

Crystal Structure of a 16 kDa Double-headed Bowman-Birk Trypsin Inhibitor from Barley Seeds at  

E-print Network

Crystal Structure of a 16 kDa Double-headed Bowman- Birk Trypsin Inhibitor from Barley Seeds at 1 The Bowman-Birk trypsin inhibitor from barley seeds (BBBI) consists of 125 amino acid residues with two inhibitory loops. Its crystal structure in the free state has been determined by the multiwavelength

Suh, Se Won

189

Effect of Light on Seed Germination of Eight Wetland Carex Species  

PubMed Central

• Background and Aims In wetland plant communities, species-specific responses to pulses of white light and to red?:?far-red light ratios can vary widely and influence plant emergence from the seed bank. Carex species are the characteristic plants of sedge meadows of natural prairie wetlands in mid-continental USA but are not returning to restored wetlands. Little is known about how light affects seed germination in these species—information which is necessary to predict seed bank emergence and to develop optimal revegetation practices. The effects of light on germination in eight Carex species from prairie wetlands were investigated. • Methods Non-dormant seeds of eight Carex species were used to determine the influence of light on germination by examining: (a) the ability of Carex seeds to germinate in the dark; (b) the effect of different lengths of exposures to white light on germination; (c) whether the effect of white light can be replaced by red light; and (d) whether the germination response of Carex seeds to white or red light is photoreversible by far-red light. • Key Results Seeds of C. brevior and C. stipata germinated >25?% in continuous darkness. Germination responses after exposure to different lengths of white light varied widely across the eight species. Carex brevior required <15?min of white light for ?50?% germination, while C. hystericina, C. comosa, C. granularis and C. vulpinoidea required ?8?h. The effect of white light was replaced by red light in all species. The induction of germination after exposure to white or red light was reversed by far-red light in all species, except C. stipata. • Conclusions The species-specific responses to simulated field light conditions suggest that (a) the light requirements for germination contribute to the formation of persistent seed banks in these species and (b) in revegetation efforts, timing seed sowing to plant community development and avoiding cover crops will improve Carex seed germination. PMID:16905568

KETTENRING, KARIN M.; GARDNER, GARY; GALATOWITSCH, SUSAN M.

2006-01-01

190

THE ROLE OF INFORMAL FARMER-TO-FARMER SEED DISTRIBUTION IN DIFFUSION OF NEW BARLEY VARIETIES IN SYRIA  

Microsoft Academic Search

SUMMARY This study examines the role, structure and effectiveness of informal seed systems in the diffusion of new barley varieties. It uses data collected by tracing farmers who received new barley varieties and other farmers who purchased seeds through farmer-to-farmer seed trade over a period of five years. The principal finding was that informal farmer-to-farmer seed dissemination was an important

ADEN AW-HASSAN; AHMED MAZID; HISHAM SALAHIEH

2008-01-01

191

Effects of chemical desiccation and early harvesting on Sorghum [Sorghum bicolor (L.) Moench] seed germination  

E-print Network

Field and laboratory experiments were conducted at two locations over two years in Texas. Objectives of these experiments were to study effects of chemical desiccation and seed maturity at harvest on sorghum seed germination. Sorghum plants were...

Gouveia, Sergio

1994-01-01

192

G Protein Signaling in the Regulation of Rice Seed Germination  

NSDL National Science Digital Library

Seed germination and early seedling growth are regulated by an intricate network of hormonal signaling pathways. The plant hormones gibberellic acid (GA) and abscisic acid (ABA) are particularly important positive and negative regulators of these processes, respectively. In the cereal rice, mutant analysis has implicated heterotrimeric guanine nucleotide–binding protein (G protein) signaling in GA-stimulated expression of several genes, including expression of the gene encoding the hydrolytic enzyme α-amylase, which breaks down carbohydrate reserves and thus mobilizes nutrients that nourish the young seedling.

Sarah M. Assmann (Penn State University;Biology Department REV)

2005-11-15

193

Quantitative trait loci analysis for rice seed vigor during the germination stage*  

PubMed Central

Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination index, were investigated using one recombinant inbred line (RIL) population derived from a cross between japonica Daguandao and indica IR28, and using the multiple interval mapping (MIM) approach. The results show that indica rice presented stronger seed vigor during the germination stage than japonica rice. A total of ten QTLs, and at least five novel alleles, were detected to control rice seed vigor, and the amount of variation (R 2) explained by an individual QTL ranged from 7.5% to 68.5%, with three major QTLs with R 2>20%. Most of the QTLs detected here are likely to coincide with QTLs for seed weight, seed size, or seed dormancy, suggesting that the rice seed vigor might be correlated with seed weight, seed size, and seed dormancy. At least five QTLs are novel alleles with no previous reports of seed vigor genes in rice, and those major or minor QTLs could be used to significantly improve the seed vigor by marker-assisted selection (MAS) in rice. PMID:21121075

Wang, Zhou-fei; Wang, Jian-fei; Bao, Yong-mei; Wang, Fu-hua; Zhang, Hong-sheng

2010-01-01

194

Frugivory and the effects of ingestion by bats on the seed germination of three pioneering plants  

NASA Astrophysics Data System (ADS)

The dispersion and seedling establishment of pioneering plants can be favoured by the presence of frugivorous bats because the bats usually improve seed germination after ingestion. Although seed germinability is known to vary greatly after ingestion by different bats, the relative contribution of each bat species to seed germination within plant communities is poorly understood. In this study, we first determined the fauna of frugivorous bats in a semideciduous seasonal forest remnant in southern Brazil and subsequently identified the plant species of the seeds passed through their guts. Second, the germination performance (i.e., germination percentage and speed) of the seeds of three pioneering plants (Piper aduncum, Piper hispidinervum and Solanum granuloso-leprosum) ingested by the most abundant bats was compared with that of the non-ingested seeds (seeds collected from fruits). Additionally, the effects on seed germination of different bat species were compared. During one year, five species of frugivorous bats were caught, and the seeds of eleven identifiable plant species (not counting those of undetermined species) were found in their faeces. We found that the germination performance of the seeds of Piper species was significantly enhanced after ingestion by bats, whereas S. granuloso-leprosum seeds had neutral or reduced germinability when seeds in faeces were compared with pulp-removed seeds. Our results revealed that the bat species that were captured exerted different effects upon seed germination; such a disparity is expected to result in different rates of early establishment of these pioneer plants in tropical forests, most likely affecting forest composition and structure, particularly during the initial stages of succession.

de Carvalho-Ricardo, Maria C.; Uieda, Wilson; Fonseca, Renata Cristina B.; Rossi, Marcelo N.

2014-02-01

195

Modulation of anti-oxidation ability by proanthocyanidins during germination of Arabidopsis thaliana seeds.  

PubMed

Proanthocyanidins (PAs) as the end products of flavonoid biosynthetic pathway mainly accumulate in seed coat but their biological function is largely unknown. We studied the anti-oxidation ability in seed coat and germination changes under externally applied oxidative stresses in PAs-deficient mutants of Arabidopsis. Germination of PAs-deficient mutant seeds was faster than that of wild-type under low or no oxidative stress, suggesting a PAs-induced inhibition of germination. When the applied oxidative stress was high, germination of PAs-deficient mutants was lower than that of wild-type, suggesting a loss of PAs-related anti-oxidation ability in the mutants. Using ABA signaling mutants, our studies demonstrated that both ABA signaling pathway and PAs were important for the response to serve oxidative stress during seed germination. However, the discrepancy of the response between abi mutants and PAs mutants to oxidative stress suggests that ABA signaling pathway may not play a major role in PAs' action in alleviating oxidative stress. Under low or no oxidative stress, germination was mainly determined by the ABA content in seed and the PAs-deficient mutant seeds germinated faster due to their lower ABA content than wild-type. However, oxidative injury inhibited germination when PAs-deficient seeds germinated under high oxidative stress. Wild-type exhibited higher germination under the high oxidative stress due to the PAs' anti-oxidation ability. Oxidative stress applied externally led to changes in endogenous PAs contents that coincided with the expression changes of PAs biogenesis genes. PAs modulated the activities of some key enzymes that controlled the levels of reactive oxygen species and the anti-oxidation capacity during the seed germination. This work suggests that PAs contribute to the adaptive mechanism that helps germination under environmental stresses by playing dual roles in both germination control and anti-oxidation reaction. PMID:22115918

Jia, Li-Guo; Sheng, Zi-Wei; Xu, Wei-Feng; Li, Ying-Xuan; Liu, Ying-Gao; Xia, Yi-Ji; Zhang, Jian-Hua

2012-03-01

196

Physiological and antioxidant responses of three leguminous species to saline environment during seed germination stage  

Microsoft Academic Search

The study investigated the physiological behaviors and antioxidant responses of Medicago sativa, Melilotus officinalis and Astragalus adsurgens to saline environment during seed germination stage. At 300 mM NaCl treatments, the final germination percentage of M. officinalis was much higher than that of M. sativa and of A. adsurgens and the initiation of germination process of A. adsurgens was 5 days

Xiaoshan Wang; Guoqi Zhao; Hongru Gu

197

Nutritional potential and functional properties of germinated mung bean, pea and lentil seeds  

Microsoft Academic Search

Mung bean, pea and lentil seeds were germinated for 72 hr and 120 hr at room temperature (25 ± 2 °C) to determine the changes in their chemical composition, antinutritional factors, in vitro digestibility and functional properties. Germination caused a significant (p p p p p p < 0.05) improved with increase in germination time while fat absorption decreased.

T. A. El-Adawy; E. H. Rahma; A. A. El-Bedawey; A. E. El-Beltagy

2003-01-01

198

Amylolytic activity in germinated Agrostemma githago L. seeds.  

PubMed

The perisperm of seeds of Agrostemma githago contains starch reserves which constitute 40% of the dry weight of the mature seed. These starch reserves were mostly broken down between 48 and 96 h after initiation of imbibition. (Germination occurred after 24 h.) The mode of starch degradation showed close parallels with the breakdown of the starchy endosperm in cereals. Thus, between 24 and 96 h the cotyledons secreted ?-amylase (EC 3.2.1.1) whereas other degradative enzymes in the perisperm, ?-amylase (EC 3.2.1.2) and maltase (EC 3.2.1.20), appeared to originate in the perisperm itself. Cotyledons secreted similar levels of ?-amylase in the presence and absence of exogenous starch, indicating that secretion is an internal developmental event of the embryo. By isoelectric focussing the secreted ?-amylase was separated into two isoenzymes. In the cotyledons, several other starch-degrading isoenzymes were present but were not secreted. PMID:24233738

de Klerk, G J; Willekens, P; Kok, H; Jacobsen, J V

1986-05-01

199

Ethylene-, light-, and prechill-enhanced germination of Echinacea angustifolia seeds  

SciTech Connect

Echinacea angustifolia DC., the common coneflower of the western Great Plains, is difficult to propagate by achenes due to inherent seed dormancy. The effects of light and prechilling on seed germination were examined, alone and combined with scarification (mechanical, acid) and ethylene (ethephon) treatments. The results showed that a 2-week prechill treatment combined with ethephon and continuous light, followed by a 2-week germination period in light (16 hours per day) at 25 C, could induce >95% seed germination in E. angustifolia. This was a significantly higher percentage of germination over a shorter period of time than any other method examined or previously described. This treatment also synchronized germination, with most viable seeds germinating in <1 week after being placed at 25 C in the light. Chemical name used: 2-chloroethylphosphonic acid (ethephon).

Feghahati, S.M.J.; Reese, R.N. (South Dakota State Univ., Brookings, SD (United States). Dept. of Biology and Microbiology)

1994-07-01

200

OSMOTIC STRESS-INDUCED CHANGES IN GERMINATION, GROWTH AND SOLUBLE SUGAR CONTENT OF SORGHUM BICOLOR (L.) MOENCH SEEDS  

Microsoft Academic Search

Summary. The effect of osmotic stress on germination, growth and soluble sugar content in Sorghum bicolor (L.) Moench cv. CSH 9 seeds and seedling components (endosperm and embryos) during early germination was inves- tigated. Under stress conditions germination decreased markedly, whereas the control at the same time reached its maximum germination (99%). A high percentage (67%) of ungerminated seeds from

Prabhjot Kaur Gill; Arun Dev Sharma; Prabhjeet Singh; Sukdev Singh Bhullar

2002-01-01

201

Earthworm-mediated maternal effects on seed germination and seedling growth in three annual plants  

Microsoft Academic Search

Many ecological studies have pointed out maternal effects in plants and shown that plant maternal environment influences germination of their seed and subsequent seedling growth. However, few have tested for maternal effects induced by soil macroorganisms. We tested whether two earthworm species (Aporrectodea caliginosa and Lumbricus terrestris) trigger such maternal effects on seed germination and seedling growth of three plant

Kam-Rigne Laossi; Diana-Cristina Noguera; Sébastien Barot

2010-01-01

202

Viability Testing of Orchid Seed and the Promotion of Colouration and Germination  

Microsoft Academic Search

This study reports the ability of Fusarium to induce orchid seed colouration and germination. The in vitro bioassay germination test, using a Fusarium isolate from the protocorm of Cypripedium reginae, was compared with standard chemical procedures of triphenyl tetrazolium chloride (TTC) and acid fuchsin (AC) for testing seed viability. With Cypripedium reginae, Cypripedium parviflorum and Platanthera grandiflora, the efficiency of

Vladimir Vujanovic; Marc St-Arnaud; Denis Barabé; Geneviève Thibeault

2000-01-01

203

Temperature requirements for dormancy break and seed germination vary greatly among 14 wetland Carex species  

Microsoft Academic Search

We evaluated dormancy loss in seeds of 14 Carex species (C. atherodes, C. brevior, C. comosa, C. cristatella, C. cryptolepis, C. granularis, C. hystericina, C. lacustris, C. pellita, C. scoparia, C. stipata, C. stricta, C. utriculata, C. vulpinoidea) under growing season and stratification conditions and determined the temperature requirements for germination. Seeds were germinated for 1 year at a diel

Karin M. Kettenring; Susan M. Galatowitsch

2007-01-01

204

Seed biology of Australian arid zone species: Germination of 18 species used for rehabilitation  

Microsoft Academic Search

Revegetation of disturbed land, particularly in arid environments, is often hindered by low seedling establishment. Information on seed biology and germination cues of keystone species is lacking, particularly in arid Australia; a major zone for mining developments. This study investigated seed characteristics and germination of 18 common species required for rehabilitation of disturbed areas at Shark Bay Salt in the

L. E. Commander; D. J. Merritt; D. P. Rokich; K. W. Dixon

2009-01-01

205

Utilization of the Main Storage Protein in Germinating Seeds of Buckwheat: Mechanism and Regulation  

Microsoft Academic Search

The main storage protein of buckwheat Fagopyrum esculentum Moench seeds the 13S globulin is utilized during germination in 5 days. Degradation of 13 S globulin is carried out by a sequential action of proteolytic enzymes present in dry and germinating seeds (metalloproteinase, cysteine proteinase, carboxypeptidase and aspartic proteinase). The rate of proteolysis is controlled by an endogenous inhibitor, embryonic axis,

Mikhail A. Belozersky; Yakov E. Dunaevsky

1995-01-01

206

SEED GERMINATION AND ROOT ELONGATION TOXICITY TESTS IN HAZARDOUS WASTE SITE EVALUATION: METHODS DEVELOPMENT AND APPLICATIONS  

EPA Science Inventory

Seed germination tests measure soil toxicity directly, while root elongation tests consider the indirect effects of water-soluble constituents which may be present in site-samples. n the seed germination toxicity test, site-soil is mixed with a reference soil to yield exposure co...

207

DIACYLGLYCEROL ACYLTRANSFERASE ACTIVITY AND TRIACYLGLYCEROL SYNTHESIS IN GERMINATING CASTOR SEED COTYLEDONS  

Technology Transfer Automated Retrieval System (TEKTRAN)

The central importance of storage lipid breakdown in providing carbon and energy during seed germination has been demonstrated by the isolation of genes encoding the enzymes involved in fatty acid '-oxidation. In contrast, little is known about the ability of germinating seeds to synthesize triacyl...

208

Isolation and Structural Identification of Sucrose Esters from Corn Spurrey ( Spergula arvensis ); Inhibition of Seed Germination  

Microsoft Academic Search

Polar as well as nonpolar extracts of Spergula arvensis (corn spurrey) were shown to cause inhibition of seed germination. The polar methylene chloride extracts were subjected to solvent partitioning and separations by a combination of silicic acid and Sephadex LH-20 column chromatography. All chromatographic fractions were monitored by a proso-millet seed germination assay, which resulted in the isolation of a

Joseph K. Peterson; Maurice E. Snook; Howard F. Harrison; Patricia F. Mason

1998-01-01

209

Effect of sand burial depth on seed germination and seedling emergence of Calligonum L. species  

Microsoft Academic Search

A greenhouse study was conducted to determine the effects of sand burial on seed germination and seedling emergence of ten Calligonum L. species. The results suggested that the deeper the seeds in sand, the lower and slower their germination and seedling emergence. Seedling emergence occurred from a maximum depth of 12 cm with most seedlings emerging from 2 and 4

Jun Ren; Ling Tao; Xin-Min Liu

2002-01-01

210

Soil Texture Involvement in Germination and Emergence of Buried Weed Seeds  

Microsoft Academic Search

studied in an ecological perspective to identify the physi- ological causes that prevent deeply buried seed from Laboratory trials were performed to test germination and emer- germinating; results obtained so far suggest this is partly gence characteristics of jimsonweed (Datura stramonium L.) seeds buried in 10 different soil types (with or without the control of soil due to the lack

Stefano Benvenuti

2003-01-01

211

Phytochrome Regulation and Differential Expression of Gibberellin 3Hydroxylase Genes in Germinating Arabidopsis Seeds  

Microsoft Academic Search

Despite extensive studies on the roles of phytochrome in photostimulated seed germination, the mechanisms downstream of the photoreceptor that promote germination are largely unknown. Previous studies have indicated that light-induced germination of Arabidopsis seeds is mediated by the hormone gibberellin (GA). Using RNA gel blot analyses, we studied the regulation of two Arabidopsis genes, GA4 and GA4H (for GA4 homolog),

Shinjiro Yamaguchi; Maria W. Smith; Robert G. S. Brown; Yuji Kamiya; Tai-ping Sun

1998-01-01

212

Effects of stress temperatures of germination on polyamine titers of soybean seeds  

NASA Astrophysics Data System (ADS)

High and low stress temperatures during seed germination and seedling development limit total germination and the rate of germination and growth. Changes in polyamine (PA) concentrations in seeds of different species have been associated with germination, growth and environmental stresses such as temperature, drought, oxygen, chilling injury and osmotic conditions. Two studies were conducted to determine the effect of stress temperatures during germination and seedling development on polyamine titers in soybean seeds. Three germination temperatures, 25, 30, and 36°C were used in the first study to evaluate their influence on changes in polyamine concentrations in soybean seeds germinated at 76 and 90 hours. The polyamines (PAs), cadaverine (Cad), putrescine (Put), spermidine (Spd), agmatine (Agm), and spermine (Spin) were quantified by HPLC using a cation exchange column and an electrochemical detector. Cad, Put, Agm, and Spd declined as the germination temperatures increased from 25 to 36°C. Conversely, Spin increased considerably with an increase in temperature. Total germination was reduced from 97.2 to 92.5% as germination temperatures increased from 25 to 36°C. Germination time did not affect Cad, Agm and Spm, and total germination, however, the interaction between temperature and germination time for Put and Spd concentrations was significant. In the second study, changes in PA concentrations, seedling growth, germination time (t50), fresh and dry weight, and moisture content were measured in the embryonic axis and cotyledons of soybean seeds germinated at 10 and 25°C through six stages of germination dry seed (DS), testa split (TS), radicle at 10 mm (Ra-10), root hairs visible (RHV), secondary root primordia (SRP), and complete seedling (CS). The concentrations of Cad and Put in the embryonic axis, were significantly higher in seeds germinated under low temperature than in seeds at 25°C (approximately 10 and 3 fold respectively). However, this difference was not observed until the last three stages of germination. The stage of germination also influenced the levels of these polyamines. The concentrations of Cad and Put detected at the CS stage were 50 and 18 fold respectively, relative to the initial concentrations found at the DS stage. Spd levels in seeds under stress temperatures also increased, but to a lesser extent compared to Cad and Put. Differences in Spd concentrations between temperatures were observed only at the CS stage. Agm concentrations were higher at 25 than at 10°C at SRP and CS. Spm concentrations of seeds germinated at 25°C remained higher during the first four stages of development but at the end of germination, seeds at 10°C had higher quantities of Spm. In the cotyledons, Polyamines tended to decline with stages of germination, regardless of the temperature. However, Agm levels increased in the cotyledons of soybean seeds. Maximum dry weight and seedling growth was found at RHV, SRP, and CS. Maximum levels of Cad and Put were also found during these stages. Spd increased with both temperatures from DS to Ra-10, thereafter, Spd levels in seeds at 10°C continued increasing while seeds at 25°C declined. High and low stress germination temperatures caused significant changes in polyamine concentrations, reduced germination and seedling growth of soybean seeds.

Pineda-Mejia, Renan

213

Comparison of light-regulated seed germination in Ficus spp. and Cecropia obtusifolia: ecological implications.  

PubMed

The major components of annual seed deposition in the rain forest at Los Tuxtlas, Veracruz, México are seeds of the pioneer tree species Cecropia obtusifolia and those of some species of Ficus. Cecropia obtusifolia Bertol. forms a relatively persistent viable soil seed bank, whereas seeds of Ficus are seldom found in the soil. Both genera require light for seed germination; however, the species differ in their germination responses to far red (FR) light under laboratory and field conditions. Seeds of C. obtusifolia did not germinate in low red/far red (R/FR) or pure FR, whereas seeds of the Ficus species did. This suggests that Ficus seeds do not become dormant under the light conditions (low R/FR ratio) beneath the leaf canopy of the rain forest. This difference may explain why the species differ in their presence in the soil seed bank. PMID:14871679

Vázquez-Yanes, C; Rojas-Aréchiga, M; Sánchez-Coronado, M E; Orozco-Segovia, A

1996-10-01

214

Estimation of scavenging capacity of melatonin and other antioxidants: contribution and evaluation in germinated seeds.  

PubMed

Seven edible seeds for the levels of melatonin, phenolic compounds and their antioxidant capacity were evaluated during germination process. Radical scavenging parameters were also studied in standard antioxidants to understand their antiradical actions. Germination brought about significant increases of total phenol compounds in all edible seeds, showing red cabbage, radish and broccoli the highest contents (21.6, 20.4 and 16.4 mg GAE/g DW, respectively). The concentration of melatonin is greatly variable in edible seeds, exhibiting significant increases during germination. The highest levels were found in red cabbage (857 pg/g DW) radish (536 pg/g DW) and broccoli (439 pg/g DW). The germinated seeds which had the highest levels of polyphenols and melatonin were those that showed the most relevant antiradical activities (>97%). This information is valuable for the incorporation of red cabbage, radish and broccoli germinated seeds into the diet to promote potential health benefits. PMID:25306336

Aguilera, Yolanda; Herrera, Teresa; Benítez, Vanesa; Arribas, Silvia M; López de Pablo, Angel L; Esteban, Rosa M; Martín-Cabrejas, María A

2015-03-01

215

Campanulaceae: a family with small seeds that require light for germination  

PubMed Central

Background and Aims The Campanulaceae is a large cosmopolitan family, but is understudied in terms of germination, and seed biology in general. Small seed mass (usually in the range 10–200 µg) is a noteworthy trait of the family, and having small seeds is commonly associated with a light requirement. Thus, the purpose of this study was to investigate the effect of light on germination in 131 taxa of the Campanulaceae family, from all five continents of its distribution. Methods For all taxa, seed germination was tested in light (8 or 12 h photoperiod) and continuous darkness under constant and alternating temperatures. For four taxa, the effect of light on germination was examined over a wide range of temperatures on a thermogradient plate, and the possible substitution of the light requirement by gibberellic acid and nitrate was examined in ten taxa. Key Results For all 131 taxa, seed germination was higher in light than in darkness for every temperature tested. Across species, the light requirement decreased significantly with increasing seed mass. For larger seeded species, germination in the dark reached higher levels under alternating than under constant temperatures. Gibberellic acid promoted germination in darkness whereas nitrates partially substituted for a light requirement only in species showing some dark germination. Conclusions A light requirement for germination, observed in virtually all taxa examined, constitutes a collective characteristic of the family. It is postulated that smaller seeded taxa might germinate only on the soil surface or at shallow depths, while larger seeded species might additionally germinate when buried in the soil if cued to do so by fluctuating temperatures. PMID:24232382

Koutsovoulou, Katerina; Daws, Matthew I.; Thanos, Costas A.

2014-01-01

216

Seed Dispersal and Germination Traits of 70 Plant Species Inhabiting the Gurbantunggut Desert in Northwest China  

PubMed Central

Seed dispersal and germination were examined for 70 species from the cold Gurbantunggut Desert in northwest China. Mean and range (3 orders of magnitude) of seed mass were smaller and narrower than those in other floras (5–8 orders of magnitude), which implies that selection favors relatively smaller seeds in this desert. We identified five dispersal syndromes (anemochory, zoochory, autochory, barochory, and ombrohydrochory), and anemochorous species were most abundant. Seed mass (F = 3.50, P = 0.01), seed size (F = 8.31, P < 0.01), and seed shape (F = 2.62, P = 0.04) differed significantly among the five dispersal syndromes and barochorous species were significantly smaller and rounder than the others. There were no significant correlations between seed mass (seed weight) (P = 0.15), seed size (P = 0.38), or seed shape (variance) (P = 0.95) and germination percentage. However, germination percentages differed significantly among the dispersal syndromes (F = 3.64, P = 0.01) and seeds of ombrohydrochorous species had higher germination percentages than those of the other species. In the Gurbantunggut Desert, the percentage of species with seed dormancy was about 80%. In general, our studies suggest that adaptive strategies in seed dispersal and germination of plants in this area are closely related to the environment in which they live and that they are influenced by natural selection forces. PMID:25485296

Liu, Huiliang; Zhang, Daoyuan; Yang, Xuejun; Huang, Zhenying; Duan, Shimin; Wang, Xiyong

2014-01-01

217

Sense transformation reveals a novel role for class I b-1,3-glucanase in tobacco seed germination  

E-print Network

Sense transformation reveals a novel role for class I b-1,3-glucanase in tobacco seed germination in tobacco seed germination, is preceded by induction of class I b-1,3-glucanase (bGLUI) in the micropylar-ripening, endosperm-limited seed germination, gene function, b-1,3- glucanase, sense transformation. Introduction

Leubner, Gerhard

218

The promotive effect of smoke derived from burnt native vegetation on seed germination of Western Australian plants  

Microsoft Academic Search

Exposure of dormant seed to cold smoke derived from burnt native vegetation had a positive influence on germination in one or more seed provenances in 45 out of 94 species of native Western Australian plants that are normally hard to germinate. When tested under controlled conditions some species showed earlier germination in smoke treatments than controls; in others smoke-treated seeds

Kingsley W. Dixon; Shauna Roche; John S. Pate

1995-01-01

219

Biorhythms in conifer seed germination during extended J.P. Barnett1 N.I. Mamonov2  

E-print Network

Biorhythms in conifer seed germination during extended storage J.P. Barnett1 N.I. Mamonov2 ! U A proportion of sound seeds of conifer species do not germinate during certain periods of the year, even when conditions are favorable. Mamonov et al., (1986) report that the non-germinating seeds have apparently

Boyer, Edmond

220

Endosperm-limited Brassicaceae Seed Germination: Abscisic Acid Inhibits Embryo-induced Endosperm Weakening of Lepidium sativum (cress) and  

E-print Network

Endosperm-limited Brassicaceae Seed Germination: Abscisic Acid Inhibits Embryo-induced Endosperm results suggest that the control of radicle protrusion during the germination of Brassicaceae seeds endosperm tissue between the embryo and the testa. The process of seed germination begins with water uptake

Leubner, Gerhard

221

In Vivo Cell Wall Loosening by Hydroxyl Radicals during Cress Seed Germination and Elongation Growth1[W][OA  

E-print Network

In Vivo Cell Wall Loosening by Hydroxyl Radicals during Cress Seed Germination and Elongation, including seed germination, elongation growth, and fruit ripening. Here, we report direct in vivo evidence for hydroxyl radical (Ã?OH)-mediated cell wall loosening during plant seed germination and seedling growth. We

Leubner, Gerhard

222

Barley (Hordeum vulgare L.) low phytic acid 1-1: an endosperm-specific filial determinant of seed total phosphorus  

Technology Transfer Automated Retrieval System (TEKTRAN)

In cultivated cereal and legume seed crops, inositol hexaphosphate (Ins P6 or “phytic acid”) typically accounts for 75% (±10%) of seed total phosphorus (P). Genetic blocks in seed Ins P6 accumulation in some cases can also alter the distribution or total amount of seed P. In non-mutant barley (Horde...

223

[Effect of acid rain on seed germination of rice, wheat and rape].  

PubMed

Rice, wheat and rape seeds were treated with simulated acid rain at pH 2.0, 2.5, 3.0, 3.5, 4.0 and 5.0 levels for 7 days in order to understand the effects of acid rain on seed germination of various acid-fast plant. The germination test showed that seed germination was absolutely inhibited at pH 2.0 for three species. Rice and wheat seeds germinated abnormally at pH 2.5. WhenpH values above 3.0, percentage germination, germination energy, germination index, vigor index of rice, wheat and rape seeds increased in relation with decreased acidity levels. In contrast, the percentage of abnormal germination of rice and wheat decreased. The experiment data about physiological aspect demonstrated that water absorption rate, respiratory rate and storage reserve transformation rate of rice, wheat and rape seeds also increased with increased pH values. The storage loss of rice and wheat increased with increased pH values but that of rape decreased. Inhibition index of shoot and root length of three kinds of seeds decreased in relation with increased pH values. The amplitude difference of index of rice was lower than that of wheat, and wheat was lower than that of rape. The experiment data showed that rice had stronger fastness than wheat and rape, wheat had stronger fastness than rape under acid rain stress. PMID:15859434

Zeng, Qing-ling; Huang, Xiao-hua; Zhou, Qing

2005-01-01

224

cGMP is required for seed germination in Arabidopsis thaliana.  

PubMed

Cyclic guanosine 3',5'-monophosphate (cGMP) is an important second messenger in animals, and is emerging as a player in regulatory functions in plants. In this study, we investigated the role of cGMP in seed germination in Arabidopsis thaliana (Col-0). We demonstrated that both, a membrane-permeant analogue of cGMP (8-Br-cGMP) and the cyclic nucleotide phosphodiesterase (PDE) inhibitor Tadalafil promoted A. thaliana seed germination, whereas the guanylate cyclase inhibitor LY 83583 (6-anilino-5,8-quinolinedione; LY) inhibited it. LY blocked gibberellic acid (GA)-induced seed germination, whereas GA and 8-Br-cGMP co-treatment increased the germination rate and more effectively overcame LY-inhibition than 8-Br-cGMP alone. The gibberellin biosynthesis inhibitor paclobutrazol (PAC) also blocked 8-Br-cGMP and Tadalafil promotion of seed germination. Furthermore, 8-Br-cGMP and Tadalafil decreased abscisic acid (ABA) sensitivity during seed germination. These findings highlight that cGMP is a positive regulator and plays a crucial role in Arabidopsis seed germination. Furthermore, both GA and cGMP are required for seed germination. PMID:20170981

Teng, Yao; Xu, Wenzhong; Ma, Mi

2010-07-15

225

Geographic variation in the flood-induced fluctuating temperature requirement for germination in Setaria parviflora seeds.  

PubMed

Our aim was to search for specific seed germinative strategies related to flooding escape in Setaria parviflora, a common species across the Americas. For this purpose, we investigated induction after floods, in relation to fluctuating temperature requirements for germination in seeds from mountain, floodplain and successional grasslands. A laboratory experiment was conducted in which seeds were imbibed or immersed in water at 5°C. Seeds were also buried in flood-prone and upland grasslands and exhumed during the flooding season. Additionally, seeds were buried in flooded or drained grassland mesocosms. Germination of exhumed seeds was assayed at 25°C or at 20°C/30°C in the dark or in the presence of red light pulses. After submergence or soil flooding, a high fraction (>32%) of seeds from the floodplain required fluctuating temperatures to germinate. In contrast, seeds from the mountains showed maximum differences in germination between fluctuating and constant temperature treatment only after imbibition (35%) or in non-flooded soil conditions (40%). The fluctuating temperature requirement was not clearly related to the foregoing conditions in the successional grassland seeds. Maximum germination could also be attained with red light pulses to seeds from mountain and successional grasslands. Results show that the fluctuating temperature requirement might help floodplain seeds to germinate after floods, indicating a unique feature of the dormancy of S. parviflora seeds from floodplains, which suggests an adaptive advantage aimed at postponing emergence during inundation periods. In contrast, the fluctuating temperature required for germination among seeds from mountain and successional grasslands show its importance for gap detection. PMID:21668607

Mollard, F P O; Insausti, P

2011-07-01

226

Cy5 maleimide labelling for sensitive detection of free thiols in native protein extracts: identification of seed proteins targeted by barley thioredoxin h isoforms.  

PubMed Central

Barley thioredoxin h isoforms HvTrxh1 and HvTrxh2 differ in temporal and spatial distribution and in kinetic properties. Target proteins of HvTrxh1 and HvTrxh2 were identified in mature seeds and in seeds after 72 h of germination. Improvement of the established method for identification of thioredoxin-targeted proteins based on two-dimensional electrophoresis and fluorescence labelling of thiol groups was achieved by application of a highly sensitive Cy5 maleimide dye and large-format two-dimensional gels, resulting in a 10-fold increase in the observed number of labelled protein spots. The technique also provided information about accessible thiol groups in the proteins identified in the barley seed proteome. In total, 16 different putative target proteins were identified from 26 spots using tryptic in-gel digestion, matrix-assisted laser-desorption ionization-time-of-flight MS and database search. HvTrxh1 and HvTrxh2 were shown to have similar target specificity. Barley alpha-amylase/subtilisin inhibitor, previously demonstrated to be reduced by both HvTrxh1 and HvTrxh2, was among the identified target proteins, confirming the suitability of the method. Several alpha-amylase/trypsin inhibitors, some of which are already known as target proteins of thioredoxin h, and cyclophilin known as a target protein of m-type thioredoxin were also identified. Lipid transfer protein, embryospecific protein, three chitinase isoenzymes, a single-domain glyoxalase-like protein and superoxide dismutase were novel identifications of putative target proteins, suggesting new physiological roles of thioredoxin h in barley seeds. PMID:14636158

Maeda, Kenji; Finnie, Christine; Svensson, Birte

2004-01-01

227

A high-throughput seed germination assay for root parasitic plants  

PubMed Central

Background Some root-parasitic plants belonging to the Orobanche, Phelipanche or Striga genus represent one of the most destructive and intractable weed problems to agricultural production in both developed and developing countries. Compared with most of the other weeds, parasitic weeds are difficult to control by conventional methods because of their life style. The main difficulties that currently limit the development of successful control methods are the ability of the parasite to produce a tremendous number of tiny seeds that may remain viable in the soil for more than 15 years. Seed germination requires induction by stimulants present in root exudates of host plants. Researches performed on these minute seeds are until now tedious and time-consuming because germination rate is usually evaluated in Petri-dish by counting germinated seeds under a binocular microscope. Results We developed an easy and fast method for germination rate determination based on a standardized 96-well plate test coupled with spectrophotometric reading of tetrazolium salt (MTT) reduction. We adapted the Mosmann’s protocol for cell cultures to germinating seeds and determined the conditions of seed stimulation and germination, MTT staining and formazan salt solubilization required to obtain a linear relationship between absorbance and germination rate. Dose–response analyses were presented as applications of interest for assessing half maximal effective or inhibitory concentrations of germination stimulants (strigolactones) or inhibitors (ABA), respectively, using four parameter logistic curves. Conclusion The developed MTT system is simple and accurate. It yields reproducible results for germination bioassays of parasitic plant seeds. This method is adapted to high-throughput screenings of allelochemicals (stimulants, inhibitors) or biological extracts on parasitic plant seed germination, and strengthens the investigations of distinctive features of parasitic plant germination. PMID:23915294

2013-01-01

228

Modulation of reactive oxygen species by salicylic acid in arabidopsis seed germination under high salinity  

PubMed Central

Potential roles of salicylic acid (SA) on seed germination have been explored in many plant species. However, it is still controversial how SA regulates seed germination, mainly because the results have been somewhat variable, depending on plant genotypes used and experimental conditions employed. We found that SA promotes seed germination under high salinity in Arabidopsis. Seed germination of the sid2 mutant, which has a defect in SA biosynthesis, is hypersensitive to high salinity, but the inhibitory effects are reduced in the presence of physiological concentrations of SA. Abiotic stresses, including high salinity, impose oxidative stress on plants. Endogenous contents of H2O2 are higher in the sid2 mutant seeds. However, exogenous application of SA reduces endogenous level of reactive oxygen species (ROS), indicating that SA is involved in plant responses to ROS-mediated damage under abiotic stress conditions. Gibberellic acid (GA), a plant hormone closely associated with seed germination, also reverses the inhibitory effects of high salinity on seed germination and seedling establishment. Under high salinity, GA stimulates SA biosynthesis by inducing the SID2 gene. Notably, SA also induces genes encoding GA biosynthetic enzymes. These observations indicate that SA promotes seed germination under high salinity by modulating antioxidant activity through signaling crosstalks with GA. PMID:21150285

Lee, Sangmin

2010-01-01

229

Studies on seed germination and growth in weed species of rice field under salinity stress.  

PubMed

An investigation was made to see the salt tolerance of 10 weed species of rice. Properly dried and treated seeds of weed species were placed on 9 cm diameter petridishes lined with Whatman No. 1 filter paper under 6 salinity regimes, viz. 0 (control), 4, 8, 16, 24 and 32 dS m(-1). The petri dishes were then kept in germinator at 25 +/- 1.0 degrees C and 12 hr light. The number of germinated seeds were recorded daily. The final germination percentage, germination index (GI), seedling vigour index, mean germination time and time for 50% germination were estimated. Root and shoot lengths of the weed seedlings were measured at 20 days after salt application and relative growth values were calculated. Results revealed that salinity decreased final germination percentage, seed of germination as measured by GI, and shoot and root length in all the species. Germination of most of the weed seeds was completely arrested (0) at 32 dS m(-1) salinity except in E. colona (12%) and C. iria (13.9%). The species C. iria, E. colona, J. linifolia and E. crusgalli showed better germination (above 30%) upto 24 dS m(-1) salinity level and were regarded as salt-tolerant weed species. J. linifolia, F. miliacea, L. chinensis and O. sativa L. (weedy rice) were graded as moderately tolerant and S. zeylanica, S. grosus and C. difformis were regarded as least tolerant weed species. PMID:22319865

Hakim, M A; Juraimi, Abdul Shukor; Hanafi, M M; Selamat, A; Ismail, Mohd Razi; Karim, S M Rezaul

2011-09-01

230

Avian gut-passage effects on seed germination of shrubland species in Mediterranean central Chile  

Microsoft Academic Search

Effects of avian gut-passage on seed germination are important to assess the effectiveness of frugivores in woodland regeneration,\\u000a particularly in biodiversity hotspots that have a high incidence of avian frugivory. We examined the effect of avian gut-passage\\u000a on seed germination in contrast to seeds that remain uneaten in five shrub species in Mediterranean central Chile and sought\\u000a to determine the

Sharon ReidJuan; Juan J. Armesto

2011-01-01

231

Gibberellins regulate seed germination in tomato by endosperm weakening: a study with gibberellin-deficient mutants  

Microsoft Academic Search

The germination of seeds of tomato [Lycopersicon esculentum (L.) Mill.] cv. Moneymaker has been compared with that of seeds of the gibberellin-deficient dwarf-mutant line ga-1, induced in the same genetic background. Germination of tomato seeds was absolutely dependent on the presence of either endogenous or exogenous gibberellins (GAs). Gibberellin A4+7 was 1000-fold more active than commercial gibberellic acid in inducing

S. P. C. Groot; C. M. Karssen

1987-01-01

232

Phase-sequence of redroot pigweed seed germination responses to ethylene and other stimuli.  

PubMed

Phase-sequence studies showed that light, ethylene, and high temperature each enhanced germination of redroot pigweed (Amaranthus retroflexus L.) seeds when given during the first 24 hours of seed imbibition. Responses were maximal during the first 12 hours. After 48 hours all three stimuli given together caused 75% germination but each alone was ineffective. The main influence of water potential on seed germination occurred at about 24 hours, but the influence of CO(2) extended into the second and third days. Germination was reduced by water stress (-4 bars) or CO(2)-free air, but ethylene reversed the reduction even when administered after several days incubation. This suggested that environmental and hormonal factors affected redroot pigweed seeds at two distinct stages in the sequence of germination events. PMID:16661865

Schonbeck, M W; Egley, G H

1981-07-01

233

[Effects of coat and sowing depth on seed germination and early seedling growth of Quercus wutaishanica].  

PubMed

Under shade environment in glasshouse, the effects of seed coat and sowing depth (0, 2, 5, 10 or 15 cm) on seed germination and early seedling growth of Quercus wutaishanica were studied. Seed coat had obvious inhibiting effects on the germination of Q. wutaishanica seeds. The germination percentage of uncoated seeds increased significantly, averagely by 19.4% at different sowing depths. The germination index and vigor index were increased significantly and the germination was speeded in the peeling treatment. The germination percentages of uncoated and coated seeds were the highest at the sowing depth of 2 cm with 78.9% and 62.2%, respectively. The germination index and vigor index were the highest at the sowing depth of 2 cm, while the coefficient of rate of germination were the highest at the sowing depth of 5 cm. Leaf area per seedling and dry mass of seedlings increased significantly in the peeling treatment compared with those in the unpeeling treatment, but specific root length decreased significantly. The shoot height in the peeling and unpeeling treatments were the highest at the sowing depth of 5 cm with 13.8 and 14.2 cm, respectively. With the increasing of sowing depth, the basal stem diameter of seedlings increased, but tap-root length, number of lateral root and maximum of lateral root all decreased. Sowing depth had little influence on dry mass of seedlings. PMID:24765842

Yan, Xing-Fui; Qiu, Zhi-Hu; Zhang, Qiang; Zhang, Kao-Wen; Zhou, Yun-Feng

2014-01-01

234

?-amylase from starchless seeds of Trigonella foenum-graecum and its localization in germinating seeds.  

PubMed

Fenugreek (Trigonella foenum-graecum) seeds do not contain starch as carbohydrate reserve. Synthesis of starch is initiated after germination. A ?-amylase from ungerminated fenugreek seeds was purified to apparent electrophoretic homogeneity. The enzyme was purified 210 fold with specific activity of 732.59 units/mg. Mr of the denatured enzyme as determined from SDS-PAGE was 58 kD while that of native enzyme calculated from size exclusion chromatography was 56 kD. Furthermore, its identity was confirmed to be ?-amylase from MALDI-TOF analysis. The optimum pH and temperature was found to be 5.0 and 50°C, respectively. Starch was hydrolyzed at highest rate and enzyme showed a Km of 1.58 mg/mL with it. Antibodies against purified Fenugreek ?-amylase were generated in rabbits. These antibodies were used for localization of enzyme in the cotyledon during different stages of germination using fluorescence and confocal microscopy. Fenugreek ?-amylase was found to be the major starch degrading enzyme depending on the high amount of enzyme present as compared to ?-amylase and also its localization at the periphery of amyloplasts. A new finding in terms of its association with protophloem was observed. Thus, this enzyme appears to be important for germination of seeds. PMID:24551136

Srivastava, Garima; Kayastha, Arvind M

2014-01-01

235

Proanthocyanidins inhibit seed germination by maintaining a high level of abscisic acid in Arabidopsis thaliana.  

PubMed

Proanthocyanidins (PAs) are the main products of the flavonoid biosynthetic pathway in seeds, but their biological function during seed germination is still unclear. We observed that seed germination is delayed with the increase of exogenous PA concentration in Arabidopsis. A similar inhibitory effect occurred in peeled Brassica napus seeds, which was observed by measuring radicle elongation. Using abscisic acid (ABA), a biosynthetic and metabolic inhibitor, and gene expression analysis by real-time polymerase chain reaction, we found that the inhibitory effect of PAs on seed germination is due to their promotion of ABA via de novo biogenesis, rather than by any inhibition of its degradation. Consistent with the relationship between PA content and ABA accumulation in seeds, PA-deficient mutants maintain a lower level of ABA compared with wild-types during germination. Our data suggest that PA distribution in the seed coat can act as a doorkeeper to seed germination. PA regulation of seed germination is mediated by the ABA signaling pathway. PMID:22765383

Jia, Liguo; Wu, Qiuyu; Ye, Nenghui; Liu, Rui; Shi, Lu; Xu, Weifeng; Zhi, Hui; Rahman, A N M Rubaiyath Bin; Xia, Yiji; Zhang, Jianhua

2012-09-01

236

Germination rate of Phyllospadix japonicus seeds relative to storage methods and periods  

NASA Astrophysics Data System (ADS)

To determine the optimal storage method and longest possible storage period of Phyllospadix japonicus seeds, we examined post-storage germination rates using different storage methods and periods for P. japonicus seeds harvested in Korean coastal waters. P. japonicus seeds are classified as recalcitrant seeds with an average moisture content of 45.4%. Germination rates of P. japonicus seeds stored in seawater at 4 °C, seawater at room temperature with air supply, and an aquarium with continuous seawater circulation ranged from 35.0% to 43.5%, whereas seeds stored in seawater at 30°C, a refrigerator at -20°C, and a desiccator at room temperature did not germinate. Seeds stored at 4°C maintained germination rates of 72.5˜73.0% until 30 days of storage, but showed rapidly decreasing germination rates after 60 days and no germination after 180 days. Since few studies have investigated seed storage of P. japonicus, these results will serve as useful data for seed-based P. japonicus habitat restoration.

Park, Jung-Im; Lee, Kun-Seop; Son, Min Ho

2014-03-01

237

The Mitochondrion-Located Protein OsB12D1 Enhances Flooding Tolerance during Seed Germination and Early Seedling Growth in Rice  

PubMed Central

B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo) proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1). OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding. PMID:25089878

He, Dongli; Zhang, Hui; Yang, Pingfang

2014-01-01

238

The mitochondrion-located protein OsB12D1 enhances flooding tolerance during seed germination and early seedling growth in rice.  

PubMed

B12D belongs to a function unknown subgroup of the Balem (Barley aleurone and embryo) proteins. In our previous work on rice seed germination, we identified a B12D-like protein encoded by LOC_Os7g41350 (named OsB12D1). OsB12D1 pertains to an ancient protein family with an amino acid sequence highly conserved from moss to angiosperms. Among the six OsB12Ds, OsB12D1 is one of the major transcripts and is primarily expressed in germinating seed and root. Bioinformatics analyses indicated that OsB12D1 is an anoxic or submergence resistance-related gene. RT-PCR results showed OsB12D1 is induced remarkably in the coleoptiles or roots by flooding during seed germination and early seedling growth. The OsB12D1-overexpressed rice seeds could protrude radicles in 8 cm deep water, further exhibiting significant flooding tolerance compared to the wild type. Moreover, this tolerance was not affected by the gibberellin biosynthesis inhibitor paclobutrazol. OsB12D1 was identified in the mitochondrion by subcellular localization analysis and possibly enhances electron transport through mediating Fe and oxygen availability under flooded conditions. This work indicated that OsB12D1 is a promising gene that can help to enhance rice seedling establishment in farming practices, especially for direct seeding. PMID:25089878

He, Dongli; Zhang, Hui; Yang, Pingfang

2014-01-01

239

4',4?,7,7?-tetra-O-methylcupressuflavone inhibits seed germination of Lactuca sativa.  

PubMed

Biflavonoids have been isolated from a wide variety of plant species, but little is known about their native biological functions. Here we report a possible ecological role for biflavonoids by describing the isolation of the biflavonoid 4',4?,7,7?-tetra-O-methylcupressuflavone (1) from Araucaria columnaris and its inhibitory effect on seed germination. Compound 1 was isolated from needles of a single A. columnaris specimen and inhibited germination of Lactuca sativa seeds in a culture-dish assay; it was also detected in soil samples under the canopy where reduced germination was observed, but not in a location away from the canopy where germination was uninhibited. PMID:24628372

DeForest, Jacob C; Du, Lin; Joyner, P Matthew

2014-04-25

240

Seed germination and seedling growth of two Pseudobombax species (Malvaceae) with contrasting habitats from Brazilian Cerrado.  

PubMed

Pseudobombax tomentosum and P. longiflorum are common trees in the Cerrado region, but the former species is more common in forest edges while the later is present in open cerrado areas. This work aimed to investigate differences in seed germination and seedling growth in these species, from seed collected from Cerrado areas in Central Brazil. For this, a seed germination experiment was designed and included four replicates with 25 seeds per species; seeds were randomly distributed in the germination chamber. To evaluate initial seedling growth, seedlings height was measured up to 67 days after seedling emergence; besides, some of these seedlings were grown for biomass evaluation during nine months. Results showed that seeds of the two species had the same germinability (near 100%) and mean germination time (ca. 12 days). However, P. longiflorum showed a more spread seed germination through time, with higher values of coefficient of variation in germination time and uncertainty index; and lower values of synchronization than P. tomentosum. The two species showed basically the same growth pattern, but lower values for height of apical meristem, diameter of underground structures (mostly roots), dry mass of shoots, underground structure and total mass of seedlings in P. tomentosum were obtained, compared to P. longiflorum. Both species allocated more dry mass to underground structures in detriment of shoot. This probably allows resprouting behavior which prevents hydric stress and detrimental fire action typical of the open Cerrado areas. PMID:22208102

Mendes-Rodrigues, Clesnan; Oliveira, Paulo Eugênio; Ranal, Marli Aparecida

2011-12-01

241

Abiotic Limits for Germination of Sugarcane Seed in Relation to Environmental Spread.  

PubMed

Sugarcane is a vegetatively propagated crop and hence the production of seed and its fate in the environment has not been studied. The recent development of genetically modified sugarcane, with the aim of commercial production, requires a research effort to understand sugarcane reproductive biology. This study contributes to this understanding by defining the abiotic limits for sugarcane seed germination. Using seed from multiple genetic crosses, germination was measured under different light regimes (light and dark), temperatures (from 18 °C to 42 °C) and water potentials (from 0 MPa to -1 MPa); cardinal temperatures and base water potential of germination were estimated based on the rates of germination. We found that sugarcane seed could germinate over a broad range of temperatures (from 11 °C to 42 °C) with optima ranging from 27 °C to 36 °C depending on source of seed. Water potentials below -0.5 MPa halved the proportion of seed that germinated. By comparing these limits to the environmental conditions in areas where sugarcane grows and has the potential to produce seed, water, but not temperature, will be the main limiting factor for germination. This new information can be taken into account when evaluating any risk of weediness during the assessment of GM sugarcane. PMID:25485029

Pierre, J S; Rae, A L; Bonnett, G D

2014-01-01

242

Seed flotation and germination of salt marsh plants: The effects of stratification, salinity, and/or inundation regime  

USGS Publications Warehouse

We examined the effects of cold stratification and salinity on seed flotation of eight salt marsh species. Four of the eight species were tested for germination success under different stratification, salinity, and flooding conditions. Species were separated into two groups, four species received wet stratification and four dry stratification and fresh seeds of all species were tested for flotation and germination. Fresh seeds of seven out of eight species had flotation times independent of salinity, six of which had average flotation times of at least 50 d. Seeds of Spartina alterniflora and Spartina patens had the shortest flotation times, averaging 24 and 26 d, respectively. Following wet stratification, the flotation time of S. alterniflora seeds in higher salinity water (15 and 36 ppt) was reduced by over 75% and germination declined by more than 90%. Wet stratification reduced the flotation time of Distichlis spicata seeds in fresh water but increased seed germination from 2 to 16% in a fluctuating inundation regime. Fresh seeds of Iva frutescens and S. alternflora were capable of germination and therefore are non-dormant during dispersal. Fresh seeds of I. frutescens had similar germination to dry stratified seeds ranging 25-30%. Salinity reduced seed germination for all species except for S. alterniflora. A fluctuating inundation regime was important for seed germination of the low marsh species and for germination following cold stratification. The conditions that resulted in seeds sinking faster were similar to the conditions that resulted in higher germination for two of four species. ?? 2009 Elsevier B.V.

Elsey-Quirk, T.; Middleton, B.A.; Proffitt, C.E.

2009-01-01

243

Nitric oxide implication in the control of seed dormancy and germination  

PubMed Central

Germination ability is regulated by a combination of environmental and endogenous signals with both synergistic and antagonistic effects. Nitric oxide (NO) is a potent dormancy-releasing agent in many species, including Arabidopsis, and has been suggested to behave as an endogenous regulator of this physiological blockage. Distinct reports have also highlighted a positive impact of NO on seed germination under sub-optimal conditions. However, its molecular mode of action in the context of seed biology remains poorly documented. This review aims to focus on the implications of this radical in the control of seed dormancy and germination. The consequences of NO chemistry on the investigations on both its signaling and its targets in seeds are discussed. NO-dependent protein post-translational modifications are proposed as a key mechanism underlying NO signaling during early seed germination. PMID:24065970

Arc, Erwann; Galland, Marc; Godin, Béatrice; Cueff, Gwendal; Rajjou, Loïc

2013-01-01

244

An unusual effect of the far-red absorbing form of phytochrome: Photoinhibition of seed germination in Bromus sterilis L  

Microsoft Academic Search

Seeds ofBromus sterilis L. germinated between 80–100% in darkness at 15° C but were inhibited by exposure to white or red light for 8 h per day. Exposure to far-red light resulted in germination similar to, or less than, that of seeds maintained in darkness. Germination is not permanently inhibited by light as seeds attain maximal germination when transferred back

Janet R. Hilton

1982-01-01

245

Development of a Threshold Model to Predict Germination of Populus tomentosa Seeds after Harvest and Storage under Ambient Condition  

PubMed Central

Effects of temperature, storage time and their combination on germination of aspen (Populus tomentosa) seeds were investigated. Aspen seeds were germinated at 5 to 30°C at 5°C intervals after storage for a period of time under 28°C and 75% relative humidity. The effect of temperature on aspen seed germination could not be effectively described by the thermal time (TT) model, which underestimated the germination rate at 5°C and poorly predicted the time courses of germination at 10, 20, 25 and 30°C. A modified TT model (MTT) which assumed a two-phased linear relationship between germination rate and temperature was more accurate in predicting the germination rate and percentage and had a higher likelihood of being correct than the TT model. The maximum lifetime threshold (MLT) model accurately described the effect of storage time on seed germination across all the germination temperatures. An aging thermal time (ATT) model combining both the TT and MLT models was developed to describe the effect of both temperature and storage time on seed germination. When the ATT model was applied to germination data across all the temperatures and storage times, it produced a relatively poor fit. Adjusting the ATT model to separately fit germination data at low and high temperatures in the suboptimal range increased the models accuracy for predicting seed germination. Both the MLT and ATT models indicate that germination of aspen seeds have distinct physiological responses to temperature within a suboptimal range. PMID:23658654

Wang, Wei-Qing; Cheng, Hong-Yan; Song, Song-Quan

2013-01-01

246

A season- and gap-detection mechanism regulates seed germination of two temperate forest pioneers.  

PubMed

The survival of seedlings in temperate climate habitats depends on both temporal and spatial factors. The interaction between an internal seed dormancy mechanism and the ruling environmental conditions allows accurate cueing of germination. We analysed how environmental signals interact in seeds of temperate forest pioneer species, increasing the seed's chances of germinating in the right place at the right time. Digitalis purpurea and Scrophularia nodosa are two small-seeded herbaceous species that typically grow in vegetation gaps in European temperate forests. Seeds of both species are partially dormant at the time of dispersal in summer. This primary dormancy is released in autumn and early winter, resulting in a minimal level of physiological dormancy by late winter and early spring. We observed that physiological dormancy was induced again in seeds exhumed in late spring and in summer. Experiments in laboratory conditions revealed that primary dormancy in seeds of S nodosa was broken by cold stratification, whereas primary dormancy in D. purpurea seeds was broken by both a cold and a warm stratification. The two species differed in their response to the tested gap-detection signals, as light was the most important factor stimulating germination of D. purpurea, and seeds of S. nodosa germinated best when subjected to daily fluctuating temperatures. This study clearly indicates that the ability to germinate in response to gap-detection signals changes seasonally in temperate forest pioneers. Additionally, seeds of both species responded differently to these environmental signals, probably reflecting differences in the regeneration niche. PMID:22188020

Vranckx, G; Vandelook, F

2012-05-01

247

Morphology, ecophysiology and germination of seeds of the neotropical tree Alibertia patinoi (Rubiaceae).  

PubMed

Alibertia patinoi (Rubiaceae) is of economic and cultural importance for communities in the Colombian Pacific and Amazon regions, where it is cultivated and mature fruits are highly appreciated and consumed. Since there is a lack of knowledge of the seed physiology of this species, we describe here the germination behavior and morphometry of seeds of Alibertia patinoi, and relate them to its habitat. Fruits were collected from a mixed food crop and a commercial plantation in Guaimía village, Buenaventura, Colombia, a tropical rain forest area. We measured length, width, thickness, mass (n = 1 400), and moisture content of seeds (n = 252). Primary dormancy tests were conducted (n = 200), followed by imbibition (n=252) and germination dynamics, under different conditions of light and temperature specific to understory and forest clearings (n = 300 seeds). Finally, seed storage behavior was established (n = 100 seeds). We observed that size and mass of seeds had a narrow range of values that did not differ within or among fruits and that the species did not exhibit primary dormancy. The seeds are recalcitrant, and recently harvested seeds exhibited higher seed moisture content (ca. 44%) and continuous metabolism. The seed germination percentage was observed to be higher under the specific dense canopy forest light and temperature conditions; furthermore, neither enriched far-red light nor darkness conditions inhibited germination. We concluded that rapid germination could be the establishment strategy of this species. Also, the physiological traits (i.e., rapid germination rate, low germination requirements, absence of primary dormancy, and recalcitrant behavior) and seed size and mass, suggest that A. patinoi is adapted to conditions of mature tropical rain forests. PMID:23885573

Escobar Escobar, Diego Fernando; Torres, Alba Marina

2013-06-01

248

Proteome analysis of Norway maple (Acer platanoides L.) seeds dormancy breaking and germination: influence of abscisic and gibberellic acids  

Microsoft Academic Search

BACKGROUND: Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and

Tomasz A Paw?owski

2009-01-01

249

Propagation of the little club-spur orchid ( Platanthera clavellata) by symbiotic seed germination and its ecological implications  

Microsoft Academic Search

Propagation of the auto-pollinated terrestrial orchid, Platanthera clavellata, using symbiotic seed germination is described. Seed from three populations in the southern Appalachians (Tennessee, South Carolina, GA) were inoculated with mycorrhizal fungi (Epulorhiza spp.) in vitro; seed germination and protocorm (seedling) developmental stages were evaluated up to 1 year after sowing. Seed obtained from Tennessee and South Carolina populations had a

Lawrence W. Zettler; Cara J. Hofer

1998-01-01

250

Genetic transformation of commercial cultivars of oat (Avena sativa L.) and barley (Hordeum vulgare L.) using in vitro shoot meristematic cultures derived from germinated seedlings  

Microsoft Academic Search

Genetic transformation using shoot meristematic cultures (SMCs) derived from germinated seedlings is established in commercial\\u000a varieties of oat cv 'Garry' and barley cv 'Harrington'. Six-month-old SMCs of oat were induced on MPM and bombarded with bar and uidA; 9-month-old SMCs of barley were induced on an improved medium (MPM-MC) containing maltose and high levels of copper and\\u000a bombarded with bar\\/nptII

S. Zhang; M.-J. Cho; T. Koprek; R. Yun; P. Bregitzer; P. G. Lemaux

1999-01-01

251

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes  

USGS Publications Warehouse

The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three saltmarsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and management.

Espinar, J.L.; Garcia, L.V.; Clemente, L.

2005-01-01

252

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes.  

PubMed

The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three salt-marsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and management. PMID:21646131

Espinar, José L; García, Luis V; Clemente, Luis

2005-07-01

253

Hormonal and environmental regulation of seed germination in flixweed ( Descurainia sophia )  

Microsoft Academic Search

Flixweed is one of the most abundant weeds in North America and China, and causes a reduction in crop yields. Dormancy of flixweed seeds is deep at maturity and is maintained in soil for several months. To identify regulators of seed dormancy and germination of flixweed, the effect of environmental and hormonal signals were examined using dormant and non-dormant seeds.

Weiqiang Li; Xiaojing Liu; Mohammad A. Khan; Yuji Kamiya; Shinjiro Yamaguchi

2005-01-01

254

AtEXP2 Is Involved in Seed Germination and Abiotic Stress Response in Arabidopsis  

PubMed Central

Expansins are cell wall proteins that promote cell wall loosening by inducing pH-dependent cell wall extension and stress relaxation. Expansins are required in a series of physiological developmental processes in higher plants such as seed germination. Here we identified an Arabidopsis expansin gene AtEXPA2 that is exclusively expressed in germinating seeds and the mutant shows delayed germination, suggesting that AtEXP2 is involved in controlling seed germination. Exogenous GA application increased the expression level of AtEXP2 during seed germination, while ABA application had no effect on AtEXP2 expression. Furthermore, the analysis of DELLA mutants show that RGL1, RGL2, RGA, GAI are all involved in repressing AtEXP2 expression, and RGL1 plays the most dominant role in controlling AtEXP2 expression. In stress response, exp2 mutant shows higher sensitivity than wild type in seed germination, while overexpression lines of AtEXP2 are less sensitive to salt stress and osmotic stress, exhibiting enhanced tolerance to stress treatment. Collectively, our results suggest that AtEXP2 is involved in the GA-mediated seed germination and confers salt stress and osmotic stress tolerance in Arabidopsis. PMID:24404203

Yan, An; Wu, Minjie; Yan, Limei; Hu, Rui; Ali, Imran; Gan, Yinbo

2014-01-01

255

Melatonin applied to cucumber (Cucumis sativus L.) seeds improves germination during chilling stress.  

PubMed

The relationship between germination and melatonin applied during osmo- and hydropriming was studied in cucumber seeds. The proportion of nuclei with different DNA contents, the mean ploidy and the (2C + 4C = 8C)/2C ratio in unprimed and primed, dry and imbibed at 10 degrees C seeds were established by flow cytometry. Thiobarbituric acid reactive substances and protein oxidation were also estimated. Melatonin and indole-3-acetic acid (IAA) concentrations in the seeds were determined using high-performance liquid chromatography with electrochemical detection. Being sensitive to chilling stress, seeds that germinated well (99%) at 25 degrees C showed only 30% germination at 15 degrees C, and almost no germination (4%) at 10 degrees C. Hydropriming in water improved seed germination to 50-60% at 15 degrees C and the addition of melatonin (25-100 M) also increased the rate of germination. Osmopriming in polyethylene glycol increased germination at 15 degrees C to 78%, and 98% when combined with 50 M melatonin. Osmoprimed seeds germinated even at 10 degrees C and reached 43%, and 83% when 50 M melatonin was applied. None of the treatments induced DNA synthesis, although during the first 24 hr of imbibition at 10 degrees C the mean ploidy and the (2C + 4C = 8C)/2C ratio increased, which is indicative of the advanced Phase II of germination. Hydro- and osmopriming slightly decreased IAA content in the seeds in most of the cases; only hydropriming with 100 and 500 M melatonin increased it. Melatonin protected membrane structure against peroxidation during chilling, but excessive melatonin levels in cucumber seeds (approximately 4 microg/g fresh weight) provoked oxidative changes in proteins. There is still lack of information explained clearly the role of melatonin in plant physiology. This molecule acts multidirectionally and usually is alliged to other compounds. PMID:19141087

Posmyk, Ma?gorzata M; Ba?abusta, M; Wieczorek, M; Sliwinska, E; Janas, K M

2009-03-01

256

A strong conditional mutualism limits and enhances seed dispersal and germination of a tropical palm.  

PubMed

Seed predation and seed dispersal can have strong effects on early life history stages of plants. These processes have often been studied as individual effects, but the degree to which their relative importance co-varies with seed predator abundance and how this influences seed germination rates is poorly understood. Therefore, we used a combination of observations and field experiments to determine the degree to which germination rates of the palm Astrocaryum mexicanum varied with abundance of a small mammal seed predator/disperser, Heteromys desmarestianus, in a lowland tropical forest. Patterns of abundance of the two species were strongly related; density of H. desmarestianus was low in sites with low density of A. mexicanum and vice versa. Rates of predation and dispersal of A. mexicanum seeds depended on abundance of H. desmarestianus; sites with high densities of H. desmarestianus had the highest rates of seed predation and lowest rates of seed germination, but a greater total number of seeds were dispersed and there was greater density of seedlings, saplings, and adults of A. mexicanum in these sites. When abundance of H. desmarestianus was experimentally reduced, rates of seed predation decreased, but so did dispersal of A. mexicanum seeds. Critically, rates of germination of dispersed seeds were 5 times greater than undispersed seeds. The results suggest that the relationship between A. mexicanum and H. desmarestianus is a conditional mutualism that results in a strong local effect on the abundance of each species. However, the magnitude and direction of these effects are determined by the relative strength of opposing, but related, mechanisms. A. mexicanum nuts provide H. desmarestianus with a critical food resource, and while seed predation on A. mexicanum nuts by H. desmarestianus is very intense, A. mexicanum ultimately benefits because of the relatively high germination rates of its seeds that are dispersed by H. desmarestianus. PMID:20049480

Klinger, Rob; Rejmánek, Marcel

2010-04-01

257

ABA inhibits germination but not dormancy release in mature imbibed seeds of Lolium rigidum Gaud.  

PubMed Central

Dormancy release in imbibed annual ryegrass (Lolium rigidum Gaud.) seeds is promoted in the dark but inhibited in the light. The role of abscisic acid (ABA) in inhibition of dormancy release was found to be negligible, compared with its subsequent effect on germination of dormant and non-dormant seeds. Inhibitors of ABA metabolism had the expected effects on seed germination but did not influence ABA concentration, suggesting that they act upon other (unknown) factors regulating dormancy. Although gibberellin (GA) synthesis was required for germination, the influence of exogenous GA on both germination and dormancy release was minor or non-existent. Embryo ABA concentration was the same following treatments to promote (dark stratification) and inhibit (light stratification) dormancy release; exogenous ABA had no effect on this process. However, the sensitivity of dark-stratified seeds to ABA supplied during germination was lower than that of light-stratified seeds. Therefore, although ABA definitely plays a role in the germination of annual ryegrass seeds, it is not the major factor mediating inhibition of dormancy release in imbibed seeds. PMID:19487389

Goggin, Danica E.; Steadman, Kathryn J.; Emery, R. J. Neil; Farrow, Scott C.; Benech-Arnold, Roberto L.; Powles, Stephen B.

2009-01-01

258

Comparison of the seed germination effects of synthetic analogs of strigol, gibberellic acid, cytokinins, and other plant growth regulators  

Microsoft Academic Search

Four synthetic multiring analogs of strigol, a naturally occurring sesquiterpene lactone that promotes germination of dormant seeds ofStriga (witchweed), were found to stimulate germination of dormantLactuca (lettuce) seeds. The effects on light-sensitive and light-insensitive lettuce seeds were concentration-dependent and exceeded those produced by equimolar (0.1 mM) solutions of gibberellic acid. Strigol and epistrigol promoted lettuce seed germination to a lesser

Judith M. Bradow; William J. Connick; Armand B. Pepperman

1988-01-01

259

Allelopathic influence of nodding thistle (Carduus nutans L.) seeds on germination and radicle growth of pasture plants  

Microsoft Academic Search

Bioassay experiments were used to assess the allelopathic potential of nodding thistle seeds on cumulative germination, speed of germination, and radicle elongation of five test species i.e., cocksfoot, perennial ryegrass, white clover, subterranean clover, and nodding thistle. Nodding thistle seeds inhibited germination of all species except subterranean clover in at least one of the bioassays used. Radicle elongation of all

D. A. Wardle; M. Ahmed; K. S. Nicholson

1991-01-01

260

Genetic control of germination and the effects of accelerated aging in mountain hemlock seeds and its relevance to gene conservation  

Microsoft Academic Search

Genetic control of germination parameters and the effects of accelerated aging in mountain hemlock (Tsuga mertensiana [Bong.] Carr.) seeds were investigated using standard germination tests and simulated aging, respectively. Germination parameters were studied on seeds collected from individual trees from two natural populations (Sooke and San Juan) located on southern Vancouver Island, BC. Strong genetic control was confirmed by the

Y. A. El-Kassaby; D. G. W. Edwards

1998-01-01

261

Transcriptome analysis during seed germination of elite Chinese bread wheat cultivar Jimai 20  

PubMed Central

Background Wheat seed germination directly affects wheat yield and quality. Although transcriptome and proteome analyses during seed germination have been reported in some crop plant species, dynamic transcriptome characterization during wheat seed germination has not been conducted. We performed the first comprehensive dynamic transcriptome analysis during different seed germination stages of elite Chinese bread wheat cultivar Jimai 20 using the Affymetrix Wheat Genome Array. Results A total of 61,703 probe sets representing 51,411 transcripts were identified during the five seed germination stages of Jimai 20, of which 2,825 differential expression probe sets corresponding to 2,646 transcripts with different functions were declared by ANOVA and a randomized variance model. The seed germination process included a rapid initial uptake phase (0–12 hours after imbibition [HAI]), a plateau phase (12–24 HAI), and a further water uptake phase (24–48 HAI), corresponding to switches from the degradation of small-molecule sucrose to the metabolism of three major nutrients and to photosynthesis. Hierarchical cluster and MapMan analyses revealed changes in several significant metabolism pathways during seed germination as well as related functional groups. The signal pathway networks constructed with KEGG showed three important genes encoding the phosphofructokinase family protein, with fructose-1, 6-bisphosphatase, and UTP-glucose-1-phosphate uridylyltransferase located at the center, indicating their pivotal roles in the glycolytic pathway, gluconeogenesis, and glycogenesis, respectively. Several significant pathways were selected to establish a metabolic pathway network according to their degree value, which allowed us to find the pathways vital to seed germination. Furthermore, 51 genes involved in transport, signaling pathway, development, lipid metabolism, defense response, nitrogen metabolism, and transcription regulation were analyzed by gene co-expression network with a k-core algorithm to determine which play pivotal roles in germination. Twenty-three meaningful genes were found, and quantitative RT-PCR analysis validated the expression patterns of 12 significant genes. Conclusions Wheat seed germination comprises three distinct phases and includes complicated regulation networks involving a large number of genes. These genes belong to many functional groups, and their co-regulations guarantee regular germination. Our results provide new insight into metabolic changes during seed germination and interactions between some significant genes. PMID:24410729

2014-01-01

262

A Comparison Of Barley Malt Amylolytic Enzyme Thermostabilities As Indicators Of Malt Sugar Concentrations  

Technology Transfer Automated Retrieval System (TEKTRAN)

This study was conducted to test the hypothesis that barley malt amylolytic enzyme thermostabilities would correlate negatively with malt sugar concentrations. Seeds of four two-row and four six-row North American elite barley cultivars were steeped and germinated in a micromalter for 6 days. At 2...

263

A proteomic analysis of rice seed germination as affected by high temperature and ABA treatment.  

PubMed

Seed germination is a critical phase in the plant life cycle, but the specific events associated with seed germination are still not fully understood. In this study, we used two-dimensional gel electrophoresis followed by mass spectrometry to investigate the changes in the proteome during imbibition of Oryza sativa seeds at optimal temperature with or without abscisic acid (ABA) and high temperature (germination thermoinhibition) to further identify and quantify key proteins required for seed germination. A total of 121 protein spots showed a significant change in abundance (1.5-fold increase/decrease) during germination under all conditions. Among these proteins, we found seven proteins specifically associated with seed germination including glycosyl hydrolases family 38 protein, granule-bound starch synthase 1, Os03g0842900 (putative steroleosin-B), N-carbamoylputrescine amidase, spermidine synthase 1, tubulin ?-1 chain and glutelin type-A; and a total of 20 imbibition response proteins involved in energy metabolism, cell growth, cell defense and storage proteins. High temperature inhibited seed germination by decreasing the abundance of proteins involved in methionine metabolism, amino acid biosynthesis, energy metabolism, reserve degradation, protein folding and stress responses. ABA treatment inhibited germination and decreased the abundance of proteins associated with methionine metabolism, energy production and cell division. Our results show that changes in many biological processes including energy metabolism, protein synthesis and cell defense and rescue occurred as a result of all treatments, while enzymes involved in methionine metabolism and weakening of cell wall specifically accumulated when the seeds germinated at the optimal temperature. PMID:25270993

Liu, Shu-Jun; Xu, Heng-Heng; Wang, Wei-Qing; Li, Ni; Wang, Wei-Ping; Møller, Ian Max; Song, Song-Quan

2014-10-01

264

A NOVEL NONINVASIVE TECHNIQUE TO MONITOR REAL-TIME OXYGEN UPTAKE DURING SEED GERMINATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

We report here a technique that allows real-time monitoring of oxygen consumption during seed germination. Germination, which begins with rehydration of the dormant tissue and is technically complete once embryo growth and emergence occurs, does not lend itself to easy and frequent monitoring. For...

265

Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes  

Microsoft Academic Search

The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three salt- marsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable

J. L. Espinar; L. V. Garcia; L. Clemente

2005-01-01

266

STRESS TEST WITH HYDROGEN PEROXIDE: SUGAR BEET SEED GERMINATION IN SOLUTION REFLECTS RELATIVE EMERGENCE POTENTIAL  

Technology Transfer Automated Retrieval System (TEKTRAN)

Investigation of sugar beet seed germination in water, hydrogen peroxide, and other solutions has revealed insights into the mechanism of seedling vigor in beets. Results showed that germination in solution reflected the relative emergence potential of sugar beet in the field. Experiments at East ...

267

A NOVEL TECHNIQUE TO MONITOR OXYGEN CONSUMPTION DURING EARLY STAGES OF SEED GERMINATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Germination is basically a reversal of maturation involving rehydration and reactivation of metabolism and meristematic growth. During the early phase of germination, 0-24 hr after planting, many soil-borne pathogens can attack the seed and cause devastating diseases. Changes in metabolic activity...

268

Effects of different pre-sowing seed treatments on germination of 10 Calligonum species  

Microsoft Academic Search

A greenhouse experiment was conducted to study the effects of abrasion, sulphuric acid, boiling water, cold stratification and seed exudate treatments on the germination of 10 Calligonum species. That are dominant shrubs used for restoration of desert vegetation in mobile sand dunes and stabilized sand fields in the northern desert of China. Little is known about their germination characteristics. In

Jun Ren; Ling Tao

2004-01-01

269

Soil warming increases plant species richness but decreases germination from the alpine soil seed bank.  

PubMed

Global warming is occurring more rapidly above the treeline than at lower elevations and alpine areas are predicted to experience above average warming in the future. Temperature is a primary factor in stimulating seed germination and regulating changes in seed dormancy status. Thus, plant regeneration from seed will be crucial to the persistence, migration and post disturbance recruitment of alpine plants in future climates. Here, we present the first assessment of the impact of soil warming on germination from the persistent alpine soil seed bank. Contrary to expectations, soil warming lead to reduced overall germination from the soil seed bank. However, germination response to soil temperature was species specific such that total species richness actually increased by nine with soil warming. We further explored the system by assessing the prevalence of seed dormancy and germination response to soil disturbance, the frequency of which is predicted to increase under climate change. Seeds of a significant proportion of species demonstrated physiological dormancy mechanisms and germination of several species appeared to be intrinsically linked to soil disturbance. In addition, we found no evidence of subalpine species and little evidence of exotic weed species in the soil, suggesting that the soil seed bank will not facilitate their invasion of the alpine zone. In conclusion, changes in recruitment via the alpine soil seed bank can be expected under climate change, as a result of altered dormancy alleviation and germination cues. Furthermore, the alpine soil seed bank, and the species richness therein, has the potential to help maintain local species diversity, support species range shift and moderate species dominance. Implications for alpine management and areas for further study are also discussed. PMID:23505066

Hoyle, Gemma L; Venn, Susanna E; Steadman, Kathryn J; Good, Roger B; McAuliffe, Edward J; Williams, Emlyn R; Nicotra, Adrienne B

2013-05-01

270

Two cytosolic glutamine synthetase isoforms play specific roles for seed germination and seed yield structure in Arabidopsis.  

PubMed

Nitrogen (N) remobilization from reserves to sinks is essential for seedling establishment and seed production. Cytosolic glutamine synthetase (GS1) is up-regulated during both seed germination and seed filling in plants. However, the specific roles of the individual GS1 isogenes with respect to N remobilization, early seedling vigour, and final seed productivity are not known. In this study, impairment of seed germination and seedling establishment is demonstrated in the single knockout mutant gln1;2, and the double knockout mutant gln1;1:gln1;2. The negative effect of Gln1;2 deficiency was associated with reduced N remobilization from the cotyledons and could be fully alleviated by exogenous N supply. Following reproductive growth, both the single and double Gln1;2-knockout mutants showed decreased seed yield due to fewer siliques, less seeds per silique, and lower dry weight per seed. The gln1;1 single mutant had normal seed yield structure but primary root development during seed germination was reduced in the presence of external N. Gln1;2 promoter-green fluorescent protein constructs showed that Gln1;2 localizes to the vascular cells of roots, petals, and stamens. It is concluded that Gln1;2 plays an important role in N remobilization for both seedling establishment and seed production in Arabidopsis. PMID:25316065

Guan, M; Møller, I S; Schjoerring, J K

2015-01-01

271

The effect of volatile and gaseous metabolites of swelling seeds on germination of fungal spores.  

PubMed

Effects of volatile and gaseous metabolites of swelling seeds of pea, bean, wheat, corn cucumber, tomato, lentil, carrot, red papper and lettuce on germination of spores of five genera of fungi were found to depend rather on the fungal than on the plant genus. Germination of spores of Botrytis cinerea, Mucor racemosus and Trichoderma viride was most severely inhibited. Spores of Verticillium dahliae were less sensitive and germination of spores of Fusarium oxysporum was inhibited only in two cases. On the other hand, exudates of pea and bean stimulated germination of spores of Fusarium oxysporum. Also spores of Trichoderma viride germinated better in an atmosphere enriched with exuded metabolites of swelling lettuce seeds. When carbon dioxide produced by the swelling seeds was absorbed in potassium hydroxide, spores of Trichoderma viride and Verticillium dahliae did not germinate at all, the inhibitory effects of volatile and gaseous exudates on germination of spores of Mucor racemosus were accentuated, and also the percentage of germinated spores of Fusarium oxysporum decreased. Germination of spores of Botrytis cinerea was not influenced. Absorption of volatile and gaseous metabolites in a solution of potassium permanganate decreased in most cases their inhibitory effects, particularly in Botrytis cinerea. PMID:1176038

Catsk?, V; Afifi, A F; Vancura, V

1975-01-01

272

Effect of distillery effluent on seed germination in some vegetable crops.  

PubMed

A laboratory experiment was conducted to study the effect of different concentrations (0%, 5%, 10%, 15%, 20%, 25%, 50%, 75% and 100%) of distillery effluent (raw spent wash) on seed germination (%), speed of germination, peak value and germination value in some vegetable crops: tomato, chilli, bottle gourd, cucumber and onion. The distillery effluent did not show any inhibitory effect on seed germination at low concentration except in tomato, but in onion the germination was significantly higher (84%) at 10% concentration as against 63% in the control. Irrespective of the crop species, at highest concentrations (75% and 100%), complete failure of germination was observed. The speed of germination, peak value and germination value also followed a similar trend. We found that a concentration of 5% was critical for seed germination in tomato and bottle gourd, and 25% in the rest of the crops. Based on the tolerance to distillery effluent, the crops studied have been arranged in the following order: cucumber > chilli > onion > bottle gourd > tomato. We conclude that the effect of the distillery effluent is crop-specific and due care should be taken before using the distillery effluent for pre-sowing irrigation purposes. PMID:11991076

Ramana, S; Biswas, A K; Kundu, S; Saha, J K; Yadava, R B R

2002-05-01

273

New cross talk between ROS, ABA and auxin controlling seed maturation and germination unraveled in APX6 deficient Arabidopsis seeds.  

PubMed

Successful execution of germination program greatly depends on the seeds' oxidative homeostasis. We recently identified new roles for the H2O2-reducing enzyme ascorbate peroxidase 6 (APX6) in germination control and seeds' stress tolerance. APX6 replaces APX1 as the dominant APX in dry seeds, and its loss-of-function results in reduced germination due to over accumulation of ROS and oxidative damage. Metabolic analyses in dry apx6 seeds, revealed altered homeostasis of primary metabolites including accumulation of TCA cycle metabolites, ABA and auxin, supporting a novel role for APX6 in regulating cellular metabolism. Increased sensitivity of apx6 mutants to ABA or IAA in germination assays indicated impaired perception of these signals. Relative suppression of ABI3 and ABI5 expression, and induction of ABI4, suggested the activation of a signaling route inhibiting germination in apx6 seeds that is independent of ABI3. Here we provide additional evidence linking ABI4 with ABA- and auxin-controlled inhibition of germination and suggest a hypothetical model for the role of APX6 in the regulation of the crosstalk between these hormones and ROS. PMID:25482750

Chen, Changming; Twito, Shir; Miller, Gad

2014-12-01

274

Seed germination of montane forest species in response to ash, smoke and heat shock in Mexico  

NASA Astrophysics Data System (ADS)

In many fire-prone ecosystems, seed germination is triggered by heat shock, smoke, ash and charred wood. However, few studies concerning the effect of these fire products on the germination of tropical and subtropical species exist. We assessed the effect of fire products and their interactions on seed germination in 12 species that frequently grow in burned areas of pine-oak and mixed forest in a mountainous subtropical area. Each species was exposed to a predetermined treatment of heat shock, which was optimised in accordance with a previous study. For smoke treatments, seeds were immersed in smoke water, whereas for ash treatments, 1.5 g of ash was added to the incubation medium. Germination increased in 92% of the species in response to the products of fire. Both the smoke water and the ash treatments promoted germination in four species that had permeable seed covers and physiological dormancy. Six species with physical dormancy required both heat shock and smoke water or ash to break dormancy. Our results indicate that seed germination response to fire products depends on the species and/or dormancy type. The germination response to the fire products varied between species; therefore, fire products may influence the species composition in post-fire regeneration.

Zuloaga-Aguilar, Susana; Briones, Oscar; Orozco-Segovia, Alma

2011-05-01

275

Seed dormancy and germination of Ficus lundellii and tropical forest restoration.  

PubMed

We investigated seed dormancy and germination in Ficus lundellii Standl. (Moraceae), a native species of Mexico's Los Tuxtlas tropical rain forest. In an 8-h photoperiod at an alternating diurnal (16/8 h) temperature of 20/30 degrees C, germination was essentially complete (96%) within 28 days, whereas in darkness, all seeds remained dormant. Neither potassium nitrate (0.05-0.2%) applied continuously nor gibberellic acid applied either continuously (10-200 ppm) or as a 24 hour pretreatment (2000 ppm) induced germination in the dark. Germination in the light was not reduced by a 24-h hydrochloric acid (0.1-1%) pretreatment, but it was reduced both by a 24-h pretreatment with either H(2)O(2) (0.1-5 M) or 5% HCl, or by more than 5 days of storage at 40 degrees C (4.5% seed water content). In a study with a 2-dimensional temperature gradient plate, seeds germinated fully and rapidly in the light at a constant temperature of 30 degrees C, and fully but less rapidly in the light at alternating temperatures with low amplitudes (< 12 degrees C) about the optimal constant temperature. The base, optimal and ceiling temperatures for rate of germination were estimated as 13.8, 30.1 and 41.1 degrees C, respectively. In all temperature regimes, light was essential for the germination of F. lundellii seeds. PMID:16203717

Garcia, Ximena; Hong, Tran D; Ellis, Richard H

2006-01-01

276

Exogenous nitric oxide improves seed germination in wheat against mitochondrial oxidative damage induced by high salinity  

Microsoft Academic Search

Effects of exogenous nitric oxide (NO) on starch degradation, oxidation in mitochondria and K+\\/Na+ accumulation during seed germination of wheat were investigated under a high salinity level. Seeds of winter wheat (Triticum aestivum L., cv. Huaimai 17) were pre-soaked with 0mM or 0.1mM of sodium nitroprusside (SNP, as nitric oxide donor) for 20h just before germination under 300mM NaCl. At

Chunfang Zheng; Dong Jiang; Fulai Liu; Tingbo Dai; Weicheng Liu; Qi Jing; Weixing Cao

2009-01-01

277

Analysis of the dual role of phytochrome in the photoinhibition of seed germination  

Microsoft Academic Search

Light can both promote and inhibit germination, even of seeds of the same species1-3. Many seeds considered to be positively photoblastic are inhibited by prolonged irradiation with light of a wide variety of spectral qualities, including those, such as sunlight, that promote germination when given as a short exposure4. The promoting effect of light is mediated by the red\\/far-red reversible

Michael R. Bartley; Barry Frankland

1982-01-01

278

Exogenous application of gibberellins to hasten yaupon seed germination for surface mine reclamation  

E-print Network

EXOGENOUS APPLICATION OF GIBBERELLINS TO HASTEN YAUPON SEED GERMINATION FOR SURFACE MINE RECLAMATION A Thesis by CHRISTOPHER MARC WHATLEY Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE DECEMBER 1988 Major Subject: Forestry EXOGENOUS APPLICATION OF GIBBERELLINS TO HASTEN YAUPON SEED GERMINATION FOR SURFACE MINE RECLAMATION A Thesis by CHRISTOPHER MARC WHATLEY Approved as to style...

Whatley, Christopher Marc

1988-01-01

279

Action Spectra for Phytochrome A- and B-Specific Photoinduction of Seed Germination in Arabidopsis thaliana  

Microsoft Academic Search

We have examined the seed germination in Arabidopsis thaliana of wild type (wt), and phytochrome A (PhyA)- and B (PhyB)-mutants in terms of incubation time and environmental light effects. Seed germination of the wt and PhyA-null mutant (phyA) was photoreversibly regulated by red and far-red lights of 10-1,000 mu mol m-2 when incubated in darkness for 1-14 hr, but no

Tomoko Shinomura; Akira Nagatani; Hiroko Hanzawa; Mamoru Kubota; Masakatsu Watanabe; Masaki Furuya

1996-01-01

280

QTLs for Seed Vigor-Related Traits Identified in Maize Seeds Germinated under Artificial Aging Conditions  

PubMed Central

High seed vigor is important for agricultural production due to the associated potential for increased growth and productivity. However, a better understanding of the underlying molecular mechanisms is required because the genetic basis for seed vigor remains unknown. We used single-nucleotide polymorphism (SNP) markers to map quantitative trait loci (QTLs) for four seed vigor traits in two connected recombinant inbred line (RIL) maize populations under four treatment conditions during seed germination. Sixty-five QTLs distributed between the two populations were identified and a meta-analysis was used to integrate genetic maps. Sixty-one initially identified QTLs were integrated into 18 meta-QTLs (mQTLs). Initial QTLs with contribution to phenotypic variation values of R2>10% were integrated into mQTLs. Twenty-three candidate genes for association with seed vigor traits coincided with 13 mQTLs. The candidate genes had functions in the glycolytic pathway and in protein metabolism. QTLs with major effects (R2>10%) were identified under at least one treatment condition for mQTL2, mQTL3-2, and mQTL3-4. Candidate genes included a calcium-dependent protein kinase gene (302810918) involved in signal transduction that mapped in the mQTL3-2 interval associated with germination energy (GE) and germination percentage (GP), and an hsp20/alpha crystallin family protein gene (At5g51440) that mapped in the mQTL3-4 interval associated with GE and GP. Two initial QTLs with a major effect under at least two treatment conditions were identified for mQTL5-2. A cucumisin-like Ser protease gene (At5g67360) mapped in the mQTL5-2 interval associated with GP. The chromosome regions for mQTL2, mQTL3-2, mQTL3-4, and mQTL5-2 may be hot spots for QTLs related to seed vigor traits. The mQTLs and candidate genes identified in this study provide valuable information for the identification of additional quantitative trait genes. PMID:24651614

Han, Zanping; Ku, Lixia; Zhang, Zhenzhen; Zhang, Jun; Guo, ShuLei; Liu, Haiying; Zhao, Ruifang; Ren, Zhenzhen; Zhang, Liangkun; Su, Huihui; Dong, Lei; Chen, Yanhui

2014-01-01

281

Modification of radiation-induced oxic and anoxic damage by caffeine and potassium permanganate in barley seeds.  

PubMed

We show that both the immediate and post-irradiation oxygen effects in barley seeds decrease in magnitude in the presence of potassium permanganate and caffeine. This implies that these two types of oxygen effect have features in common. With the removal of the radiation-induced oxygen-sensitive sites, by anoxic hydration, caffeine potentiates the oxygen-independent component of damage, in seeds irradiated in a dry or pre-soaked state. Potassium permangenate, on the other hand, enhances the anoxic radiation damage only in seeds irradiated in a dry state. The possible mode of action of KMnO4 and caffeine in barley seeds is discussed. PMID:1086298

Kesavan, P C; Dodd, N J

1976-08-01

282

12-Oxo-Phytodienoic Acid Accumulation during Seed Development Represses Seed Germination in Arabidopsis[C][W][OA  

PubMed Central

Arabidopsis thaliana COMATOSE (CTS) encodes an ABC transporter involved in peroxisomal import of substrates for ?-oxidation. Various cts alleles and mutants disrupted in steps of peroxisomal ?-oxidation have previously been reported to exhibit a severe block on seed germination. Oxylipin analysis on cts, acyl CoA oxidase1 acyl CoA oxidase2 (acx1 acx2), and keto acyl thiolase2 dry seeds revealed that they contain elevated levels of 12-oxo-phytodienoic acid (OPDA), jasmonic acid (JA), and JA-Ile. Oxylipin and transcriptomic analysis showed that accumulation of these oxylipins occurs during late seed maturation in cts. Analysis of double mutants generated by crossing cts with mutants in the JA biosynthesis pathway indicate that OPDA, rather than JA or JA-Ile, contributes to the block on germination in cts seeds. We found that OPDA was more effective at inhibiting wild-type germination than was JA and that this effect was independent of CORONATINE INSENSITIVE1 but was synergistic with abscisic acid (ABA). Consistent with this, OPDA treatment increased ABA INSENSITIVE5 protein abundance in a manner that parallels the inhibitory effect of OPDA and OPDA+ABA on seed germination. These results demonstrate that OPDA acts along with ABA to regulate seed germination in Arabidopsis. PMID:21335376

Dave, Anuja; Hernández, M. Luisa; He, Zhesi; Andriotis, Vasilios M.E.; Vaistij, Fabián E.; Larson, Tony R.; Graham, Ian A.

2011-01-01

283

Interspecific and intraspecific variation in seed size and germination requirements of Sarracenia (Sarraceniaceae).  

PubMed

Seed size and germination requirements of eight (of nine) Sarracenia species, and 13 populations of S. purpurea were studied. All species except for S. purpurea are restricted to the southeastern United States, whereas S. purpurea ranges across Canada, southward along the eastern United States into Maryland and Virginia (S. purpurea ssp. purpurea), and from New Jersey southward into northern Florida and the coast of the Gulf of Mexico (S. purpurea ssp. venosa). I tested the hypotheses that dormancy-breaking requirements vary predictably among species across a latitudinal gradient. I also sought to determine whether seed size and germination requirements were useful characters for resolving systematic and phylogenetic questions within this genus. Seed size varied significantly among species, but variability in seed size within S. purpurea exceeded the variability in seed size observed across all eight species studied. Seeds of all species are morphophysiologically dormant upon dispersal. Length of required cool, moist pretreatment varied among species, and germination in higher latitude populations is enhanced with longer pretreatment. In contrast, variability in germination requirements of subspecies, varieties, and populations of the geographically wide-ranging S. purpurea was not related clearly to geographic location (latitude or elevation). Germination requirements do not map onto a proposed phylogeny of Sarracenia, but observed differences in germination requirements of S. purpurea ssp. venosa var. burkii relative to other populations of S. purpurea support the recent proposal to elevate this variety to species status. PMID:11250820

Ellison, A M

2001-03-01

284

Thermal niche for in situ seed germination by Mediterranean mountain streams: model prediction and validation for Rhamnus persicifolia seeds  

PubMed Central

Background and Aims Mediterranean mountain species face exacting ecological conditions of rainy, cold winters and arid, hot summers, which affect seed germination phenology. In this study, a soil heat sum model was used to predict field emergence of Rhamnus persicifolia, an endemic tree species living at the edge of mountain streams of central eastern Sardinia. Methods Seeds were incubated in the light at a range of temperatures (10–25 and 25/10 °C) after different periods (up to 3 months) of cold stratification at 5 °C. Base temperatures (Tb), and thermal times for 50 % germination (?50) were calculated. Seeds were also buried in the soil in two natural populations (Rio Correboi and Rio Olai), both underneath and outside the tree canopy, and exhumed at regular intervals. Soil temperatures were recorded using data loggers and soil heat sum (°Cd) was calculated on the basis of the estimated Tb and soil temperatures. Key Results Cold stratification released physiological dormancy (PD), increasing final germination and widening the range of germination temperatures, indicative of a Type 2 non-deep PD. Tb was reduced from 10·5 °C for non-stratified seeds to 2·7 °C for seeds cold stratified for 3 months. The best thermal time model was obtained by fitting probit germination against log °Cd. ?50 was 2·6 log °Cd for untreated seeds and 2·17–2·19 log °Cd for stratified seeds. When ?50 values were integrated with soil heat sum estimates, field emergence was predicted from March to April and confirmed through field observations. Conclusions Tb and ?50 values facilitated model development of the thermal niche for in situ germination of R. persicifolia. These experimental approaches may be applied to model the natural regeneration patterns of other species growing on Mediterranean mountain waterways and of physiologically dormant species, with overwintering cold stratification requirement and spring germination. PMID:24201139

Porceddu, Marco; Mattana, Efisio; Pritchard, Hugh W.; Bacchetta, Gianluigi

2013-01-01

285

Seed germination of cirsium arvense and Lepidium latifolium: Implications for management of montane wetlands  

USGS Publications Warehouse

Cirsium arvense and Lepidium latifolium are species that can aggressively invade wetland margins and potentially reduce biodiversity and alter ecosystem function. Although expansion of these species primarily occurs via rhizomatous growth, seeds are thought to be important in initial establishment. We conducted this study to investigate differences in seed germination of C. arvense and L. latifolium in montane wetlands of Colorado and Wyoming, USA. We used germination chambers to simulate environmental conditions (photoperiod, day/night temperature) during three periods of the growing season at each site and evaluated seed germination in relation to three soil moisture levels and two soil depths. A combination of shallow (<1 cm) seed burial and wet conditions resulted in the greatest germination probability of C. arvense (x = 63.0%), 95% CI = 41.2-80.5%), whereas deep (2-3 cm) seed burial and saturated moisture conditions resulted in almost no germination (x?? = 0.3%, 95% CI = 0.1-1.3%). The maximum germination probability of 44.0% (CI = 28.1-61.4%) for L. latifolium also occurred in the shallow burial and wet treatment; however, only effects of seed burial were significant (P < 0.05). The estimated mean germination probability of deeply buried seeds was <1.0% (CI = 0.3-1.4%) compared to 32% (CI = 19.7-47.9%) for shallowly buried seeds. Our results suggest that each species has the ability to germinate at similar rates throughout the growing season and across a large portion of the moisture gradient. This suggests that management actions, including water-level manipulations, at any time during the growing season may stimulate germination. Although burial of seed to depths of 2-3 cm reduced the germination potential of both species, the use of mechanical implements may be problematic in established stands because new plants of both species easily sprout from root buds. Further, disturbance resulting from such actions diminishes the density and vigor of other plants already present, which may ultimately decrease the competitive resistance of the disturbed environment to invasion by outside species. Detection of new invasions is a critical component of any integrated weed management program. Our results indicate that the incidence of C. arvense and L. latifolium germination is most likely in areas with seeds that are within 1 cm of the soil surface and soil moisture is 75-100% of field capacity for extended periods. ?? 2006, The Society of Wetland Scientists.

Laubhan, M.K.; Shaffer, T.L.

2006-01-01

286

Ecology of seed dormancy and germination in sedges ( Carex)  

Microsoft Academic Search

The genus Carex, with its wide distribution and large number of species yet with a rather uniform life history, is a very convenient group for comparative studies of germination ecology at the generic level. The combination of a strict or conditional primary dormancy, a light requirement for germination, low germination at constant temperatures, a positive response to diurnal temperature fluctuations

Wolfgang Schütz

2000-01-01

287

Smoke-Induced Seed Germination in California Chaparral  

Microsoft Academic Search

The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Heat shock triggers germination of certain species but has no stimulatory effect on a great many other postfire species that are chemically stimulated by combustion products. Previous reports have shown that charred wood will induce germination, and here we report that

Jon E. Keeley; C. J. Fotheringham

1998-01-01

288

Barley (Hordeum vulgare L.) low phytic acid 1-1: an endosperm-specific, filial determinant of seed total phosphorus.  

PubMed

Inositol hexaphosphate (Ins P6 or "phytic acid") typically accounts for 75 (± 10%) of seed total phosphorus (P). In some cases, genetic blocks in seed Ins P6 accumulation can also alter the distribution or total amount of seed P. In nonmutant barley (Hordeum vulgare L.) caryopses, ~80% of Ins P6 and total P accumulate in the aleurone layer, the outer layer of the endosperm, with the remainder in the germ. In barley low phytic acid 1-1 (Hvlpa1-1) seed, both endosperm Ins P6 and total P are reduced (~45% and ~25%, respectively), but germs are phenotypically wild type. This translates into a net reduction in whole-seed total P of ~15%. Nutrient culture studies demonstrate that the reduction in endosperm total P is not due to a reduction in the uptake of P into the maternal plant. Genetic tests (analyses of testcross and F2 seed) reveal that the Hvlpa1-1 genotype of the filial seed conditions the seed total P reduction; sibling seed in the same head of barley that differ in their Hvlpa1-1 genotype (heterozygous vs. homozygous recessive) differ in their total P (normal vs. reduced, respectively). Therefore, Hvlpa1 functions as a seed-specific or filial determinant of barley endosperm total P. PMID:25080466

Raboy, Victor; Cichy, Karen; Peterson, Kevin; Reichman, Sarah; Sompong, Utumporn; Srinives, Peerasak; Saneoka, Hirofumi

2014-01-01

289

Cytochrome C oxidase activity in germinating Phaseolus vulgaris l. seeds: Effects of carbon monoxide  

SciTech Connect

Cytochrome c oxidase is a key bioenergetic enzyme required for seed germination. The enzyme was isolated from 2-day germinating beans and biochemically compared to its bovine heart counterpart. Carbon monoxide, which binds to the heme a{sub 3} site of cytochrome c oxidase, we used to probe O{sub 2} utilization activity in isolated enzyme, mitochondrial particles, and whole seeds. Bean seeds under 80% CO/20% O{sub 2} exhibited 46% growth inhibition as determined by root length. Reversible, dose-dependent partial inhibition of bean seed mitochondrial respiration was observed in the presence of CO; heart mitochondria had a more sensitive, less reversible response. Effects of CO on bean and bovine heart enzyme were similar. The close correlation of CO effects observed on seedling growth, mitochondrial respiration and cytochrome oxidase activity indicate an important role for this enzyme during the early stages of seed germination.

Caughey, W.S. (Colorado State Univ., Fort Collins (USA)); Sowa, S.; Roos, E.E.

1989-04-01

290

A study of the effects of micro-gravity on seed germination  

NASA Technical Reports Server (NTRS)

This study will identify characteristics of seed germination dependent upon gravity. To accomplish this objective, four different seed types will be germinated in space and then be compared to a control group germinated on Earth. Both the experimental and control groups will be analyzed on the cellular level for the size of cells, structural anomalies, and gravitational effects. The experiment will be conducted in a Get Away Special Canister (GAS Can no. 608) owned by the U.S. Space and Rocket Center and designed for students. The GAS Can will remain in the cargo bay of the Space Shuttle with minimal astronaut interaction.

Klein, Lynn Suzanne; Mckibben, Mark; Brain, David A.; Johnson, Theodore C.; Dannenberg, Konrad K.

1992-01-01

291

Seed germination, seedling emergence, seed persistence and triflusulfuron-methyl sensitivity in Galinsoga parviflora and G. quadriradiata.  

PubMed

Galinsoga quadriradiota Ruiz and Pavon (hairy galinsoga) and Galinsogo parviflora Cav. (smaliflower galinsoga, gallant soldier) are very troublesome weeds in many vegetable row crops in Europe. In order to optimize further management strategies for Galinsoga control in-depth study of germination biology was performed. Germination experiments were conducted to evaluate the impact of light and alternating temperatures on germination of a large set of Galinsoga populations. Seedling emergence was investigated by burying seeds at different depths in a sand and sandy loam soil. Dormancy of fresh achenes harvested in autumn was evaluated by studying germination response in light at 25/20 degrees C with and without nitrate addition. Seed longevity was investigated in an accelerated ageing experiment by exposing seeds to 45 degrees C and 100% relative humidity. A dose-response pot experiment was conducted in the greenhouse to evaluate the effectiveness of triflusulfuron-methyl, applied at the one leaf pair stage, for controlling Belgian Galinsoga populations. Galinsoga seeds required light for germination; light dependency varied among populations. Seedling emergence decreased drastically with increasing burial depth. Maximum depth of emergence varied between 4 and 10mm depending on soil type and population. In a sandy soil, emergence percentages were higher and seedlings were able to emerge from greater depths than in a sandy loam soil. Freshly produced G. parviflora seeds showed a varying but high degree of primary dormancy and were less persistent than G. quadriradiata seeds which lack primary dormancy. Galinsoga parviflora populations were more sensitive to triflusulfuron-methyl than G. quadriradiata populations. The lack of primary dormancy, high seed persistence and lower herbicide sensitivity may explain the higher distribution and abundance of G. quadriradiata over G. parviflora populations in Belgium. Overall, features such as lack of primary dormancy of freshly harvested G. quadriradiata seeds and light dependency for germination may be used to optimize and develop Galinsoga management strategies. PMID:25151846

De Cauwer, B; Devos, R; Claerhout, S; Bulcke, R; Reheul, D

2013-01-01

292

Seed Germination and Reproductive Features of Lysimachia minoricensis (Primulaceae), a Wild?extinct Plant  

PubMed Central

Lysimachia minoricensis is one of the few Mediterranean endemic plants (Minorca, Balearic islands) that has gone extinct in the wild but which persists as extant germplasm or cultivated plants in several botanical gardens. Reproductive features (seed set, number of seeds per capsule, seed weight) and germination responses to constant temperatures, sea water and dry?heat pre?treatments were investigated to determine the extent to which they may have influenced the extinction of the species. Seed set in Lysimachia is not dependent on pollinators, suggesting a functional selfer breeding system. Most plants produced a large mean number of fruits (23·2) and seeds (46·6), and the mean production of seeds per individual was estimated to be almost 1100. Overall, no highly specific requirements were observed for seed germination. Seed germination was not inhibited in the dark, and a high germinability (over 87 % in all cases) was recorded in most experiments, with the exception of those performed at low temperatures (5 and 10 °C). These data suggest that fertility and seed viability were not the major causes of extinction. The high reproductive performance of L. minoricensis is in striking contrast to its status as a wild?extinct plant, suggesting that extrinsic factors were responsible for its extinction. PMID:12099529

ROSSELLÓ, JOSEP A.; MAYOL, MARIA

2002-01-01

293

Transcriptional Dynamics of Two Seed Compartments with Opposing Roles in Arabidopsis Seed Germination1[W][OPEN  

PubMed Central

Seed germination is a critical stage in the plant life cycle and the first step toward successful plant establishment. Therefore, understanding germination is of important ecological and agronomical relevance. Previous research revealed that different seed compartments (testa, endosperm, and embryo) control germination, but little is known about the underlying spatial and temporal transcriptome changes that lead to seed germination. We analyzed genome-wide expression in germinating Arabidopsis (Arabidopsis thaliana) seeds with both temporal and spatial detail and provide Web-accessible visualizations of the data reported (vseed.nottingham.ac.uk). We show the potential of this high-resolution data set for the construction of meaningful coexpression networks, which provide insight into the genetic control of germination. The data set reveals two transcriptional phases during germination that are separated by testa rupture. The first phase is marked by large transcriptome changes as the seed switches from a dry, quiescent state to a hydrated and active state. At the end of this first transcriptional phase, the number of differentially expressed genes between consecutive time points drops. This increases again at testa rupture, the start of the second transcriptional phase. Transcriptome data indicate a role for mechano-induced signaling at this stage and subsequently highlight the fates of the endosperm and radicle: senescence and growth, respectively. Finally, using a phylotranscriptomic approach, we show that expression levels of evolutionarily young genes drop during the first transcriptional phase and increase during the second phase. Evolutionarily old genes show an opposite pattern, suggesting a more conserved transcriptome prior to the completion of germination. PMID:23858430

Dekkers, Bas J.W.; Pearce, Simon; van Bolderen-Veldkamp, R.P.; Marshall, Alex; Widera, Pawe?; Gilbert, James; Drost, Hajk-Georg; Bassel, George W.; Müller, Kerstin; King, John R.; Wood, Andrew T.A.; Grosse, Ivo; Quint, Marcel; Krasnogor, Natalio; Leubner-Metzger, Gerhard; Holdsworth, Michael J.; Bentsink, Leónie

2013-01-01

294

Comparative effect of NaCl and seawater on seed germination of Suaeda salsa and Atriplex centralasiatica  

Microsoft Academic Search

Seed germination in annual halophytes usually occurs when soil salinity levels are low and soil moisture is relatively high\\u000a [1]. Optimum germination of halophyte seeds is often obtained under freshwater and inhibited by increasing salinity concentrations\\u000a [2–4], but the ability to germinate at higher salinities is varied with species, for example Salicornia herbacea germinated\\u000a at 1,700 mM NaCl [5], Arthrocnemum

Xiaojing Liu; Hailong Qiao; Weiqiang Li; Toshiaki Tadano; M. Ajmal Khan

295

Proteomics of Arabidopsis Seed Germination : a Comparative Study of Wild-Type and Gibberellin-Deficient Seeds  

Microsoft Academic Search

We examined the role of gibberellins (GAs) in germination of Arabidopsis seeds by a proteomic approach. For that purpose, we used two systems. The first system consisted of seeds of the GA-deficient ga1 mutant, and the second corresponded to wild-type seeds incubated in paclobutrazol, a specific GA biosynthesis inhibitor. With both systems, radicle protrusion was strictly dependent on exogenous GAs.

Karine Gallardo; Claudette Job; Steven P. C. Groot; Magda Puype; J. Vandekerckhove; D. Job

2002-01-01

296

Protein dynamics during seed germination under copper stress in Arabidopsis over-expressing Potentilla superoxide dismutase.  

PubMed

Copper (Cu), though an essential micronutrient for plants, poses toxicity at higher concentrations possibly by inducing oxidative stress. With the background that enzyme superoxide dismutase (SOD) ameliorates oxidative stress, the present work focused on understanding physiological and proteomic response of Arabidopsis seeds constitutively over-expressing copper-zinc SOD of Potentilla atrosanguinea (PaSOD) during germination in response to varied concentrations of copper sulphate (Cu stress). Transgenics showed higher germination percentage and required less "mean time to germination" under Cu-stress. In response to Cu stress, 39 differentially expressed protein spots were detected by 2-D electrophoresis in proteins of germinating wild type (WT) and transgenic seeds, of which 14 spots appeared exclusively in transgenics. Among the rest 25 protein spots, 14 showed down-regulation, one showed up-regulation, and 10 spots disappeared. MALDI-TOF and subsequent peptide mass fingerprinting analysis revealed that the down-regulated proteins in transgenics were related to oxidative stress, detoxification, germination, intermediary metabolism and regulatory proteins. Up-regulated proteins in WT and down-regulated proteins in transgenic during Cu stress were the same. Changes in key proteins, vis-à-vis alleviation of oxidative stress in transgenic Arabidopsis over-expressing PaSOD possibly alleviated toxicity of Cu-induced stress during seed germination, resulting in higher germination rate and germination percentage. PMID:21479579

Gill, Tejpal; Dogra, Vivek; Kumar, Sanjay; Ahuja, Paramvir Singh; Sreenivasulu, Yelam

2012-01-01

297

Gene expression analysis of light-modulated germination in tomato seeds.  

PubMed

Tomato (Solanum lycopersicum) seed germination can be inhibited by continuous irradiation with far-red light (FRc) and re-induced by a subsequent red light pulse. In this study, we carried out a global transcript analysis of seeds subjected to FRc inhibitory treatment, with and without a subsequent red light pulse, using potato cDNA microarrays. We also identified and characterized genes involved in light-modulated germination as elements of the phytochrome signalling pathway. Microarray data showed that the inhibition of germination by FRc involves the induction of a large number of genes and the repression of a significantly smaller quantity. Multivariate analysis established an underlying pattern of expression dependent on physiological treatment and incubation time, and identified different groups of genes associated with dormancy maintenance, inhibition and promotion of germination. We showed that ELIP, CSN6, SOS2 and RBP are related to the photocontrol of germination. These genes are known to participate in other physiological processes, but their participation in germination has not been suggested previously. Light quality regulates the tomato seed transcriptome during phytochrome-modulated germination through changes in the expression of certain sets of genes. In addition, ELIP and GIGANTEA were confirmed as components of the phytochrome A signalling pathway during FRc inhibition of germination. PMID:19460109

Auge, Gabriela Alejandra; Perelman, Susana; Crocco, Carlos Daniel; Sánchez, Rodolfo Augusto; Botto, Javier Francisco

2009-01-01

298

Effects of light, hydropriming and abiotic stress on seed germination, and shoot and root growth of pyrethrum ( Tanacetum cinerariifolium)  

Microsoft Academic Search

Poor germination and seedling establishment are major problems in arid and semi-arid environments, and these characteristics are considered to be important factors in later plant growth and yield. Laboratory experiments were conducted on freshly harvested pyrethrum (Tanacetum cinerariifolium) seeds to investigate the effects of light (influenced by the seeding method) and seed hydropriming on germination, and shoot and root growth

J. Li; L. Y. Yin; M. A. Jongsma; C. Y. Wang

2011-01-01

299

The transcriptomes of dormant leafy spurge seeds under alternating temperature are differentially affected by a germination-enhancing pretreatment  

Technology Transfer Automated Retrieval System (TEKTRAN)

Seed dormancy is an important stage in the life cycle of many non-domesticated plants, often characterized by the temporary failure to germinate under conditions that normally favor the process. Pre-treating dormant imbibed seeds at a constant temperate accelerated germination of leafy spurge seeds ...

300

Seed dormancy-breaking and germination requirements of Drosera anglica , an insectivorous species of the Northern Hemisphere  

Microsoft Academic Search

Seeds of Drosera anglica collected in Sweden were dormant at maturity in late summer, and dormancy break occurred during cold stratification. Stratified seeds required light for germination, but light had to be given after temperatures were high enough to be favorable for germination. Seeds stratified in darkness at 5\\/1 °C and incubated in light at 12\\/12 h daily temperature regimes

Carol C. Baskin; Per Milberg; Lars Andersson; Jerry M. Baskin

2001-01-01

301

Thioredoxin-Linked Proteins Are Reduced during Germination of Medicago truncatula Seeds1[W][OA  

PubMed Central

Germination of cereals is accompanied by extensive change in the redox state of seed proteins. Proteins present in oxidized form in dry seeds are converted to the reduced state following imbibition. Thioredoxin (Trx) appears to play a role in this transition in cereals. It is not known, however, whether Trx-linked redox changes are restricted to cereals or whether they take place more broadly in germinating seeds. To gain information on this point, we have investigated a model legume, Medicago truncatula. Two complementary gel-based proteomic approaches were followed to identify Trx targets in seeds: Proteins were (1) labeled with a thiol-specific probe, monobromobimane (mBBr), following in vitro reduction by an NADP/Trx system, or (2) isolated on a mutant Trx affinity column. Altogether, 111 Trx-linked proteins were identified with few differences between axes and cotyledons. Fifty nine were new, 34 found previously in cereal or peanut seeds, and 18 in other plants or photosynthetic organisms. In parallel, the redox state of proteins assessed in germinating seeds using mBBr revealed that a substantial number of proteins that are oxidized or partly reduced in dry seeds became more reduced upon germination. The patterns were similar for proteins reduced in vivo during germination or in vitro by Trx. In contrast, glutathione and glutaredoxin were less effective as reductants in vitro. Overall, more than half of the potential targets identified with the mBBr labeling procedure were reduced during germination. The results provide evidence that Trx functions in the germination of seeds of dicotyledons as well as monocotyledons. PMID:17513483

Alkhalfioui, Fatima; Renard, Michelle; Vensel, William H.; Wong, Joshua; Tanaka, Charlene K.; Hurkman, William J.; Buchanan, Bob B.; Montrichard, Françoise

2007-01-01

302

Change in protein content during seed germination of a high altitude plant Podophyllum hexandrum Royle.  

PubMed

Podophyllum hexandrum Royle (=Sinopodophyllum hexandrum) is a high-altitude medicinal plant exploited for its etoposides which are potential anticancer compounds. An effective, conventional propagation method is by seed. However, seed germination is erratic, and seedling survival is low. A marginal increase in Podophyllum seed germination was attained with organic solvents. In the present study an attempt was made to decipher the physiological and biochemical barriers in terms of change in proteins during seed germination of Podophyllum. Comparative 2-DE analysis between un-germinated (dormant) and germinating seeds revealed nearly 113 differentially expressed proteins, whereas Peptide Mass Fingerprint (PMF) analysis of 97 protein spots revealed appearance of 27 proteins, up-accumulation of 11 proteins, down-accumulation of 19 proteins and disappearance of 40 proteins with germination. Identified 59 proteins in the homology search were involved in metabolism (carbohydrate and amino acid metabolism; 20 proteins), ABA/GA signaling (17 proteins) and stress (15 proteins) related proteins. Seven proteins were with unknown function. Two-DE, and MS/MS analysis in conjunction with semi-quantitative RT-PCR data of cell wall hydrolyzing genes, revealed that in Podophyllum the radicle protrusion occurs might be because of the up-accumulation of cell wall hydrolases i.e. ?-1, 3-glucanase and XET which weakens the thick walled micropylar endosperm. PMID:23153791

Dogra, Vivek; Ahuja, Paramvir Singh; Sreenivasulu, Yelam

2013-01-14

303

Proteolytic and Trypsin Inhibitor Activity in Germinating Jojoba Seeds (Simmondsia chinensis).  

PubMed

Changes in proteolytic activity (aminopeptidase, carboxypeptidase, endopeptidase) were followed during germination (imbibition through seedling development) in extracts from cotyledons of jojoba seeds (Simmondsia chinensis). After imbibition, the cotyledons contained high levels of sulfhydryl aminopeptidase activity (APA) but low levels of serine carboxypeptidase activity (CPA). CPA increased with germination through the apparent loss of a CPA inhibitor substance in the seed. Curves showing changes in endopeptidase activity (EPA) assayed at pH 4, 5, 6, 7, and 8 during germination were distinctly different. EPA at pH 4, 5, 6, and 7 showed characteristics of sulfhydryl enzymes while activity at pH 8 was probably due to a serine type enzyme. EPA at pH 6 was inhibited early in germination by one or more substances in the seed. Activities at pH 5 and later at pH 6 were the highest of all EPA throughout germination and increases in these activities were associated with a rapid loss of protein from the cotyledons of the developing seedling.Jojoba cotyledonary extracts were found to inhibit the enzymic activity of trypsin, chymotrypsin, and pepsin but not the protease from Aspergillus saotoi. The heat-labile trypsin inhibitor substance(s) was found in commercially processed jojoba seed meal and the albumin fraction of seed proteins. Trypsin inhibitor activity decreased with germination. PMID:16662104

Samac, D; Storey, R

1981-12-01

304

Proteolytic and Trypsin Inhibitor Activity in Germinating Jojoba Seeds (Simmondsia chinensis) 1  

PubMed Central

Changes in proteolytic activity (aminopeptidase, carboxypeptidase, endopeptidase) were followed during germination (imbibition through seedling development) in extracts from cotyledons of jojoba seeds (Simmondsia chinensis). After imbibition, the cotyledons contained high levels of sulfhydryl aminopeptidase activity (APA) but low levels of serine carboxypeptidase activity (CPA). CPA increased with germination through the apparent loss of a CPA inhibitor substance in the seed. Curves showing changes in endopeptidase activity (EPA) assayed at pH 4, 5, 6, 7, and 8 during germination were distinctly different. EPA at pH 4, 5, 6, and 7 showed characteristics of sulfhydryl enzymes while activity at pH 8 was probably due to a serine type enzyme. EPA at pH 6 was inhibited early in germination by one or more substances in the seed. Activities at pH 5 and later at pH 6 were the highest of all EPA throughout germination and increases in these activities were associated with a rapid loss of protein from the cotyledons of the developing seedling. Jojoba cotyledonary extracts were found to inhibit the enzymic activity of trypsin, chymotrypsin, and pepsin but not the protease from Aspergillus saotoi. The heat-labile trypsin inhibitor substance(s) was found in commercially processed jojoba seed meal and the albumin fraction of seed proteins. Trypsin inhibitor activity decreased with germination. PMID:16662104

Samac, Deborah; Storey, Richard

1981-01-01

305

Germination behaviour of seeds from herbicide treated plants of Chenopodium album L.  

PubMed

The carry-over effect of sub-lethal herbicides was investigated on the germination of seeds collected from surviving Chenopodium album plants, which had received 1/8, 1/8 twice, 1/8 three times, 1/4, 1/2, 1/1 doses of either pre-emergence ioxynil or post-emergence bentazone in a previous onion (Allium cepa) crop. Seeds were also collected from surviving C. album plants, which had received 1/4, 1/2, 1/1 of either pre-emergence pendimethalin, propachlor and linuron, or 1/8, 1/8 twice, 1/8 three times, 1/4, 1/2, 1/1 of post-emergence ioxynil or linuron in a previous leek (Allium porrum) crop. Seeds of surviving plants were collected and tested for germination at temperature of 5, 10, 15, 20 and 25 degrees C. The effect of different temperatures on the total number of germinated seeds was significant. Germination was minimum at low temperatures (5 degrees C or 10 degrees C). Herbicides did not show any effect on germination of C. album and resulted in the same final germination percentage as seeds collected from the unsprayed control plots. PMID:19893909

Tanveer, Asif; Nadeem, Muhammad A; Ali, Asghar; Tahir, Muhammad; Zamir, Muhammad S I

2009-12-01

306

Programmed cell death (PCD): an essential process of cereal seed development and germination  

PubMed Central

The life cycle of cereal seeds can be divided into two phases, development and germination, separated by a quiescent period. Seed development and germination require the growth and differentiation of new tissues, but also the ordered disappearance of cells, which takes place by a process of programmed cell death (PCD). For this reason, cereal seeds have become excellent model systems for the study of developmental PCD in plants. At early stages of seed development, maternal tissues such as the nucellus, the pericarp, and the nucellar projections undergo a progressive degeneration by PCD, which allows the remobilization of their cellular contents for nourishing new filial tissues such as the embryo and the endosperm. At a later stage, during seed maturation, the endosperm undergoes PCD, but these cells remain intact in the mature grain and their contents will not be remobilized until germination. Thus, the only tissues that remain alive when seed development is completed are the embryo axis, the scutellum and the aleurone layer. In germinating seeds, both the scutellum and the aleurone layer play essential roles in producing the hydrolytic enzymes for the mobilization of the storage compounds of the starchy endosperm, which serve to support early seedling growth. Once this function is completed, scutellum and aleurone cells undergo PCD; their contents being used to support the growth of the germinated embryo. PCD occurs with tightly controlled spatial-temporal patterns allowing coordinated fluxes of nutrients between the different seed tissues. In this review, we will summarize the current knowledge of the tissues undergoing PCD in developing and germinating cereal seeds, focussing on the biochemical features of the process. The effect of hormones and redox regulation on PCD control will be discussed. PMID:25120551

Domínguez, Fernando; Cejudo, Francisco J.

2014-01-01

307

The Effects of Seed Mass on Germination, Seedling Emergence, and Early Seedling Growth of Eastern White Pine ( Pinus strobus L.)  

Microsoft Academic Search

Half-sib seed of several eastern white pine (Pinus strobus L.) families was used to examine seed mass effects on laboratory germination, and seedling emergence and growth under moderate\\u000a and low light (47 and 13% full sunlight) in a greenhouse. Percent germination and speed of germination under laboratory conditions\\u000a were not related to seed mass among half-sib families or multi-family seedlots

William C. Parker; Thomas L. Noland; Andrée E. Morneault

2006-01-01

308

EPR studies on gamma-irradiated barley seeds: identification of trapped electrons.  

PubMed

Electron paramagnetic resonance (EPR) studies were conducted on barley seeds exposed to normal (H(2)O) and deuterated (D(2)O) moisture, irradiated with 750 Gy at 77 K. Reported here, for the first time, are the trapped electrons formed on gamma-irradiation of seeds at 77 K. Electrons are stabilized/solvated with an increase in the moisture content (H(2)O/D(2)O) of seeds. The recombination of the trapped electron with radical cation gave intense thermoluminescence emission at 110 K. With the increase in temperature and the destruction of singlet, unmasking of an underlying heterogeneous population of free radicals was observed. These free radicals emanate mainly from the endosperm (approximately 95% by wt of the seed), whereas irradiated embryos show a broad multiplet of comparatively low amplitude. Radiolysis of carbohydrate, proteins (approximately 95% of endosperm), and lipids could possibly be responsible for the heterogeneous population of free radicals. Peroxyl radicals were also observed on annealing. PMID:11714316

Shukla, L I; Natarajan, V; Devasagayam, T P; Sastry, M D; Kesavan, P C

2001-11-01

309

The Mycorrhizal Fungus, Sebacina vermifera , Enhances Seed Germination and Biomass Production in Switchgrass ( Panicum virgatum L)  

Microsoft Academic Search

Seed dormancy and slow seedling establishment are two major concerns in switchgrass (Panicum virgatum L.) production, often resulting in a poor stand with reduced productivity. Studies were conducted to investigate the stability\\u000a of artificial associations between switchgrass and the ectomycorrhizal fungus, Sebacina vermifera, and to evaluate the potential benefits of this novel association in seed germination and biomass production. All

Sita R. Ghimire; Nikki D. Charlton; Kelly D. Craven

2009-01-01

310

Seed Germination and Seedling Emergence of Three Annuals Growing on Desert Sand Dunes in China  

Microsoft Academic Search

? Background and Aims Information on the initial growth characteristics of annuals found in Chinese deserts is very limited. The aim of this study was to investigate seed germination and interactive effects of irrigation and seed burial depth in sand on seedling emergence and seedling survival in three annuals (Agriophyllum squarrosum, Bassia dasyphylla and Aristida adscensionis) commonly growing on sand

KAZUO T OBE; L IPING Z HANG

311

Seed Germination and Seedling Emergence of Three Annuals Growing on Desert Sand Dunes in China  

Microsoft Academic Search

? Background and Aims Information on the initial growth characteristics of annuals found in Chinese deserts is very limited. The aim of this study was to investigate seed germination and interactive effects of irrigation and seed burial depth in sand on seedling emergence and seedling survival in three annuals (Agriophyllum squarrosum, Bassia dasyphylla and Aristida adscensionis) commonly growing on sand

KAZUO TOBE; LIPING ZHANG; KENJI OMASA

2005-01-01

312

Ethylene, light-, and prechill-enhanced germination of Echinacea angustifolia seeds  

Microsoft Academic Search

Echinacea angustifolia DC., the common coneflower of the western Great Plains, is difficult to propagate by achenes due to inherent seed dormancy. The effects of light and prechilling on seed germination were examined, alone and combined with scarification (mechanical, acid) and ethylene (ethephon) treatments. The results showed that a 2-week prechill treatment combined with ethephon and continuous light, followed by

S. M. J. Feghahati; R. N. Reese

1994-01-01

313

Seed Germination of Some Medicinal and Aromatic Plants in Heavy Metal Environment  

Microsoft Academic Search

The effect of heavy metals (Cd, Cu, Pb, Zn) on seed germination and root growth in Pimpinella anisum L. (anise), Carum carvi L. (caraway), and Foeniculum vulgare L. (fennel) was evaluated on randomly selected samples of 50 seeds in three replicates from each of the plant species. Heavy metal test solutions were prepared from each metal at two concentrations, the

E. A. Jeliazkova; L. E. Craker

2003-01-01

314

Thioredoxin-linked proteins are reduced during germination of medicago truncatula seeds  

Technology Transfer Automated Retrieval System (TEKTRAN)

Germination of cereals is accompanied by extensive change in the redox state of seed proteins. Proteins present in oxidized (S-S) form in dry seeds are converted to the reduced (SH) state following imbibition. Thioredoxin (Trx) appears to play a role in this transition in cereals. It is not known, h...

315

Influence of the testa on seed dormancy, germination and longevity in Arabidopsis  

Microsoft Academic Search

The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by limiting the detrimental activity of physical and biological agents during seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmentation and\\/or structure for

I. Debeaujon; K. M. Léon-Kloosterziel; M. Koornneef

2000-01-01

316

Mathematical simulation of soil microclimate conditions for predicting weed seed germination  

Technology Transfer Automated Retrieval System (TEKTRAN)

Microclimate-based models for weed seed emergence are in the initial phases of development. The major driving forces of weed seed germination in the soil environment are temperature and soil moisture content. In the past these quantities have been measured at a single point (e.g., 5 cm). However, th...

317

INTERACTION OF ACCELERATED AGING AND P-COUMARIC ACID ON CRIMSON CLOVER SEED GERMINATION.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several phenolic acids, including p-coumaric acid, have been described as allelochemicals that may inhibit seed germination or seedling growth. Whether, in forage species, these effects are exacerbated by environmental stressors is not known. Accelerated seed aging (high temperature (41 C) and high...

318

Influence of the Testa on Seed Dormancy, Germination, and Longevity in Arabidopsis1  

Microsoft Academic Search

The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by lim- iting the detrimental activity of physical and biological agents dur- ing seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmen- tation

Isabelle Debeaujon; Karen M. Leon-Kloosterziel; Maarten Koornneef

2000-01-01

319

Effect of high temperatures on seed germination of two woody Leguminosae  

Microsoft Academic Search

Cytisus scoparius and Genista florida regenerate after fire by stump-sprouting but also by seed. Seeds of these species were heated to a range of temperatures similar to those registered on the surface soil during natural fires (from 50 to 150 °C) and a range of exposure times (from 1 to 15 min). No germination was observed at high temperatures, =130

R. Tarrega; L. Calvo; L. Trabaud

1992-01-01

320

Effects of Light, Cold Storage, and Temperature on Seed Germination of Golden Thistle (Scolymus hispanicus L.)  

Microsoft Academic Search

Golden thistle (Scolymus hispanicus L., family Asteraceae), is used as both a medicinal plant and a vegetable in the Mediterranean region. Although the plant grows in the wild, information to promote seed germination is needed for the cultivation necessary to meet demand. In this study, seed from two wild-grown and one cultivated source were used to determine the effect of

Ali Osman Sari; Mehmet Tutar

2010-01-01

321

Effects of Thermoperiod on Recovery of Seed Germination of Halophytes from Saline Conditions  

Microsoft Academic Search

Recovery of seed germination from NaCl salinity of desert shrubs (Haloxylon recurvum and Suaeda fruticosa, and the herbs Zygophyllum simplex and Triglochin maritima was studied under various thermoperiods. The percentage of unger- minated seeds that recovered when they were transferred to distilled water varied significantly with variation in species and thermoperiods. Zygophyllum simplex had little recovery from all NaCl concentrations

M. Ajmal Khan; Irwin A. Ungar

1997-01-01

322

Effects of accelerated aging and p-coumaric on crimson clover (Trifolium incarnatium L.) seed germination.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Several phenolic acids, including p-coumaric acid, have been described as allelochemicals that may inhibit seed germination or seedling growth. Whether these effects are exacerbated in forage species by environmental stressors is unknown. Accelerated seed aging (high temperature (41 C) and high hum...

323

Nitrogen Fertilizer and Crop Residue Effects on Seed Mortality and Germination of Eight Annual Weed Species  

E-print Network

. Mechanisms underlying soil N fertility effects on weed seed mortality appear to be species-specific. Future control over the genetics of weed populations, a moderate amount of control over the maternal environmentNitrogen Fertilizer and Crop Residue Effects on Seed Mortality and Germination of Eight Annual Weed

Sims, Gerald K.

324

PARTIAL PURIFICATION AND PROPERTIES OF LIPASE FROM GERMINATING SEEDS OF JATROPHA CURCAS L.  

Technology Transfer Automated Retrieval System (TEKTRAN)

The lipase present in the seeds of Jatropha curcas L. was isolated, partially purified, and some of its properties studied. Lipase activity was detected in both the dormant and germinating seeds. The lipase hydrolysed palm kernel, coconut, and olive oils at comparable rates (approximately 5 µg FFA...

325

THE EFFECTS OF COUMARIN ON RADISH SEED GERMINATION AND RADICLE ELONGATION  

Technology Transfer Automated Retrieval System (TEKTRAN)

Coumarin is a compound that inhibits seed germination and seedling growth. This inhibitory effect may confer a competitive advantage for the plants that secrete coumarin into the environment. This study was conducted to evaluate the effect of hydration-dehydration of radish seed in the presence of...

326

Allelopathic potential of Trifolium resupinatum and T. alexandrium on seed germination of four weed species.  

PubMed

Laboratory studies were conducted to determine the seed germination of Amaranthus retroflexus, Convolvulus arvensis, Secale cereale and Sinapis arvensis as affected by water-and methanol-soluble constituents of Persian and Berseem clovers. Aboveground tissues of the clovers were collected during flowering stage and dried. Three concentrations of aqueous and methanolic extracts were used: full-strength (33.3 g L(-1)), half-strength (16.7 g L(-1)) and quarter-strength (8.3 g L(-1)). The weed seeds were placed in petri dishes contained the legume extract, or distilled water (control). Percent seed germination was taken after a week. In general, seed germination of the weed species declined progressively with increasing concentration of the clover extracts. It was found that wild mustard exhibited the greatest sensitivity to both the legume extracts. Compared with aqueous extract, methanolic extract caused more decline in seed germination of the weeds. In addition, compared to Persian clover, Berseem clover was stronger inhibitor of seed germination. Therefore, the amounts of allelochemicals may be different in these clovers. Field bindweed showed the least sensitivity to both the legume extracts. Therefore, field bindweed had probably more tolerance to the allelochemicals produced by the clover species. PMID:19070068

Maighany, Fariba; Ghorbanli, Mahlagha; Khalghani, Javad; Najafpour, Morteza

2007-04-01

327

The study of a barley epigenetic regulator, HvDME, in seed development and under drought  

PubMed Central

Background Epigenetic factors such as DNA methylation and histone modifications regulate a wide range of processes in plant development. Cytosine methylation and demethylation exist in a dynamic balance and have been associated with gene silencing or activation, respectively. In Arabidopsis, cytosine demethylation is achieved by specific DNA glycosylases, including AtDME (DEMETER) and AtROS1 (REPRESSOR OF SILENCING1), which have been shown to play important roles in seed development. Nevertheless, studies on monocot DNA glycosylases are limited. Here we present the study of a DME homologue from barley (HvDME), an agronomically important cereal crop, during seed development and in response to conditions of drought. Results An HvDME gene, identified in GenBank, was found to encode a protein with all the characteristic modules of DME-family DNA glycosylase proteins. Phylogenetic analysis revealed a high degree of homology to other monocot DME glycosylases, and sequence divergence from the ROS1, DML2 and DML3 orthologues. The HvDME gene contains the 5? and 3? Long Terminal Repeats (LTR) of a Copia retrotransposon element within the 3? downstream region. HvDME transcripts were shown to be present both in vegetative and reproductive tissues and accumulated differentially in different seed developmental stages and in two different cultivars with varying seed size. Additionally, remarkable induction of HvDME was evidenced in response to drought treatment in a drought-tolerant barley cultivar. Moreover, variable degrees of DNA methylation in specific regions of the HvDME promoter and gene body were detected in two different cultivars. Conclusion A gene encoding a DNA glycosylase closely related to cereal DME glycosylases was characterized in barley. Expression analysis during seed development and under dehydration conditions suggested a role for HvDME in endosperm development, seed maturation, and in response to drought. Furthermore, differential DNA methylation patterns within the gene in two different cultivars suggested epigenetic regulation of HvDME. The study of a barley DME gene will contribute to our understanding of epigenetic mechanisms operating during seed development and stress response in agronomically important cereal crops. PMID:24175960

2013-01-01

328

Effect of hydration and dehydration cycles on seed germination of Aster kantoensis (Compositae)  

Microsoft Academic Search

Seeds of Aster kantoensis Kitamura (Compositae) were experimentally exposed to different cycles of hydration and dehydration: 3H1D (cycles of 3-d hydration and 1-d dehydration periods), 2H3D, 2H1D, 1H3D, 1H2D, and 1H1D. Under continuous hydration (control), all viable seeds germinated within 9 d. However, all viable seeds ex- posed to the 3H1D, 2H3D, and 2H1D cycles germinated within 36, 50, and

Mitsuko Kagaya; Takashi Tani; Naoki Kachi

2005-01-01

329

A method for the imbibition and germination of wheat seeds in space.  

PubMed

A method was developed for the reliable germination in space of wheat seeds on porous tube nutrient delivery systems. Germination paper strips were loosely rolled into cylinders and two seeds inserted close to the outer edges of each cylinder. This configuration: 1) directed the emerging shoots upward and roots downward, 2) was efficient in wicking moisture from the porous tubes, and 3) provided open areas for oxygen diffusion. Cotton tufts were inserted into the bottom crevices of the cylinders to fix the seeds in a mid-level position and cylinders were then storable (indefinitely) prior to the preprogrammed (on-orbit) initiation of imbibition. This method extends both the upper and lower ends of acceptable moisture levels for successful seed germination, increasing the probability of success for spaceflight applications where moisture availability is more variable than on Earth. PMID:11542683

Levine, H G; Piastuch, W C

1999-01-01

330

MBF1s regulate ABA-dependent germination of Arabidopsis seeds.  

PubMed

Transcriptional co-activators of the multiprotein bridging factor 1 (MBF1) controls gene expression by connecting transcription factors and the basal transcription machinery. In Arabidopsis thaliana functions of MBF1 genes have been related to stress tolerance and developmental alterations. Endogenous ABA plays a major role in the regulation of Arabidopsis seed dormancy and germination. Seed dormancy and ABA sensitivity are enhanced in ethylene insensitive mutants suggesting that ethylene signal transduction pathway is necessary to fully develop ABA-dependent germination. In this report we showed that a triple knock-down mutant for Arabidopsis MBF1 genes (abc-) has enhanced seed dormancy and displays hypersensitivity to exogenous ABA. In addition, higher ABA contents were detected in abc- seeds after imbibition. These evidences suggest a negative role of MBF1s genes in ABA-dependent inhibition of germination. The participation of MBF1s in ethylene signal transduction pathway is also discussed. PMID:22353867

Di Mauro, María Florencia; Iglesias, María José; Arce, Débora Pamela; Valle, Estela Marta; Arnold, Roberto Benech; Tsuda, Kenichi; Yamazaki, Ken-ichi; Casalongué, Claudia Anahí; Godoy, Andrea Verónica

2012-02-01

331

Modification of Seed Germination Performance through Cold Plasma Chemistry Technology  

Microsoft Academic Search

growth regulators to seeds (Silcock and Smith, 1982; Taylor and Harman, 1990; Zarnstorff et al., 1994). One This study was conducted to determine if an alternate seed treat- such treatment is seed coating, the direct application of ment approach based on plasma chemistry would offer a more viable material to a seed surface. Seeds can be treated by alternative over

John C. Volin; Ferencz S. Denes; Raymond A. Young; Scott M. T. Park

2000-01-01

332

Seed dormancy and germination in Jeffersonia dubia (Berberidaceae) as affected by temperature and gibberellic acid.  

PubMed

The genus Jeffersonia, which contains only two species, has a trans-Atlantic disjunct distribution. The aims of this study were to determine the requirements for breaking dormancy and germination of J. dubia seeds and to compare its dormancy characteristics with those of the congener in eastern North America. Ripe seeds of J. dubia contain an underdeveloped embryo and were permeable to water. In nature, seeds were dispersed in May, while embryos began to grow in September, and were fully elongated by late November. Germination started in March of the next year, and seeds emerged as seedlings soon after germination. In laboratory experiments, incubation at high temperatures (25 °C, 25/15 °C) for at least 8 weeks was required to initiate embryo growth, while a transfer to moderate temperatures (20/10 °C, 15/6 °C) was needed for the completion of embryo growth. At least 8 weeks at 5 °C was effective in overcoming physiological dormancy and for germination in seeds after the embryos had fully elongated. Thus, both high and low temperatures were essential to break dormancy. Gibberellic acid (GA3 ) treatment could substitute for the high temperature requirement, but not for the low temperature requirement. Based on the dormancy-breaking requirements, it is confirmed that the seeds have deep simple morphophysiological dormancy. This dormancy type is similar to that of seeds of the eastern North American species J. diphylla. Although seeds require 10-11 months from seed dispersal to germination in nature, under controlled conditions they required only 3 months after treatment with 1000 mg·l(-1) GA3 , followed by incubation at 15/6 °C. This represents practical knowledge for propagation of these plants from seed. PMID:25319374

Rhie, Y H; Lee, S Y; Kim, K S

2014-10-16

333

Allelopathy of the invasive plant Bidens frondosa on the seed germination of Geum japonicum var. chinense.  

PubMed

Five gradient concentrations (0.02, 0.04, 0.06, 0.08, and 0.10 g/mL) of leaching liquors from the roots, stems, and leaves of the invasive plant Bidens frondosa were used as conditioning fluid to examine its influence on seed germination conditions of the native plant Geum japonicum var. chinense in Huangshan. All leaching liquors of organs suppressed the seed germination of Geum japonicum var. chinense and reduced the final germination percentage and rate, and increased the germination inhibition rate, with a bimodal dependence on concentration. The leaching liquor inhibited the seed germination significantly at the concentration of 0.02 g/mL respectively. The seed germination was also inhibited as the concentration reached to 0.04 g/mL and beyond. Hence the allelopathic effects of the organs were significantly enhanced respectively. This phenomenon represented the presence of allelopathy substances in the root, stem and leaf of Bidens frondosa. PMID:25511044

Wang, X F; Hassani, D; Cheng, Z W; Wang, C Y; Wu, J

2014-01-01

334

Phosphorylation of the transcriptional regulator MYB44 by mitogen activated protein kinase regulates Arabidopsis seed germination.  

PubMed

The phytohormones abscisic acid (ABA) and gibberellic acid (GA) have antagonistic roles in the control of seed germination and seedling development. We report here that the transcriptional regulator MYB44 has a role in the control of seed germination in Arabidopsis thaliana. High levels of the MYB44 transcript are found in dry seeds but the transcript levels decrease during germination. The decrease in transcript level during germination is inhibited by the GA biosynthesis inhibitor paclobutrazol (PAC). MYB44 is phosphorylated by both recombinant and native forms of MPK3 and MPK6 at Ser(53) and Ser(145). Transgenic overexpression of MYB44 results in increased sensitivity of seed germination to ABA or PAC treatment. The PAC-insensitive germination phenotype of the myb44 mutant is complemented by overexpression of wild type MYB44 but not by overexpression of a mutant protein that lacks the MPK-target serines indicating that phosphorylation of MYB44 by MPKs is required for its biological function. PMID:22704933

Nguyen, Xuan Canh; Hoang, My Hanh Thi; Kim, Ho Soo; Lee, Kyunghee; Liu, Xiao-Min; Kim, Sun Ho; Bahk, Sunghwa; Park, Hyeong Cheol; Chung, Woo Sik

2012-07-13

335

ESTs Analysis Reveals Putative Genes Involved in Symbiotic Seed Germination in Dendrobium officinale  

PubMed Central

Dendrobiumofficinale (Orchidaceae) is one of the world’s most endangered plants with great medicinal value. In nature, D. officinale seeds must establish symbiotic relationships with fungi to germinate. However, the molecular events involved in the interaction between fungus and plant during this process are poorly understood. To isolate the genes involved in symbiotic germination, a suppression subtractive hybridization (SSH) cDNA library of symbiotically germinated D. officinale seeds was constructed. From this library, 1437 expressed sequence tags (ESTs) were clustered to 1074 Unigenes (including 902 singletons and 172 contigs), which were searched against the NCBI non-redundant (NR) protein database (E-value cutoff, e-5). Based on sequence similarity with known proteins, 579 differentially expressed genes in D. officinale were identified and classified into different functional categories by Gene Ontology (GO), Clusters of orthologous Groups of proteins (COGs) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The expression levels of 15 selected genes emblematic of symbiotic germination were confirmed via real-time quantitative PCR. These genes were classified into various categories, including defense and stress response, metabolism, transcriptional regulation, transport process and signal transduction pathways. All transcripts were upregulated in the symbiotically germinated seeds (SGS). The functions of these genes in symbiotic germination were predicted. Furthermore, two fungus-induced calcium-dependent protein kinases (CDPKs), which were upregulated 6.76- and 26.69-fold in SGS compared with un-germinated seeds (UGS), were cloned from D. officinale and characterized for the first time. This study provides the first global overview of genes putatively involved in D. officinale symbiotic seed germination and provides a foundation for further functional research regarding symbiotic relationships in orchids. PMID:23967335

Zhao, Ming-Ming; Zhang, Gang; Zhang, Da-Wei; Hsiao, Yu-Yun; Guo, Shun-Xing

2013-01-01

336

Gibberellin requirement for Arabidopsis seed germination is determined both by testa characteristics and embryonic abscisic acid  

Microsoft Academic Search

The mechanisms imposing a gibberellin (GA) requirement to promote the germination of dormant and non-dormant Arabidopsis seeds were analyzed using the GA-deficient mutant ga1, several seed coat pigmentation and structure mutants, and the abscisic acid (ABA)-deficient mutant aba1. Testa mutants, which exhibit reduced seed dormancy, were not resistant to GA biosynthesis inhibitors such as tetcyclacis and paclobutrazol, contrarily to what

I. Debeaujon; M. Koornneef

2000-01-01

337

Modeling Analysis on Germination and Seedling Growth Using Ultrasound Seed Pretreatment in Switchgrass  

PubMed Central

Switchgrass is a perennial C4 plant with great potential as a bioenergy source and, thus, a high demand for establishment from seed. This research investigated the effects of ultrasound treatment on germination and seedling growth in switchgrass. Using an orthogonal matrix design, conditions for the ultrasound pretreatment in switchgrass seed, including sonication time (factor A), sonication temperature (factor B) and ultrasound output power (factor C), were optimized for germinating and stimulating seedling growth (indicated as plumular and radicular lengths) through modeling analysis. The results indicate that sonication temperature (B) was the most effective factor for germination, whereas output power (C) had the largest effect on seedling growth when ultrasound treatment was used. Combined with the analyses of range, variance and models, the final optimal ultrasonic treatment conditions were sonication for 22.5 min at 39.7°C and at an output power of 348 W, which provided the greatest germination percentage and best seedling growth. For this study, the orthogonal matrix design was an efficient method for optimizing the conditions of ultrasound seed treatment on switchgrass. The electrical conductivity of seed leachates in three experimental groups (control, soaked in water only, and ultrasound treatment) was determined to investigate the effects of ultrasound on seeds and eliminate the effect of water in the ultrasound treatments. The results showed that the electrical conductivity of seed leachates during either ultrasound treatment or water bath treatment was significantly higher than that of the control, and that the ultrasound treatment had positive effects on switchgrass seeds. PMID:23071756

Wang, Quanzhen; Chen, Guo; Yersaiyiti, Hayixia; Liu, Yuan; Cui, Jian; Wu, Chunhui; Zhang, Yunwei; He, Xueqing

2012-01-01

338

Compartmentation and dynamics of flavone metabolism in dry and germinated rice seeds.  

PubMed

Among secondary metabolites, flavonoids are particularly important for the plant life cycle and could be beneficial for human health. The study of Arabidopsis thaliana transparent testa mutants showed that seed flavonoids are important for environmental adaptation, reactive oxygen species homeostasis, dormancy and longevity. Compared with Arabidopsis and maize (Zea mays L.), far less research has been conducted on rice (Oryza sativa L.) particularly for cultivars with non-pigmented seeds. In this study, we describe the localization, nature and relative abundance of flavonoids in mature and germinated non-pigmented Nipponbare seeds using a combination of confocal microscopy, mass spectrometry and gene expression analysis. The mature seed exclusively accumulates flavones mostly in the embryo and to a lesser extent in the pericarp/testa. Due to the variety of flavone conjugation patterns, 21 different flavones were identified, including sulfated flavones never mentioned before in cereals. Schaftoside (apigenin-6-C-glucoside-8-C-arabinoside) and its two isomers represent nearly 50% of all rice seed flavones and are the only flavonoids accumulated in the pericarp/testa seed compartment. These 21 conjugated flavones showed a very stable profile during rice seed germination sensu stricto, while expression of key flavone synthesis genes strongly increases before the completion of germination. We discuss the potential roles of these rice seed flavones in a seed biology context. PMID:25008975

Galland, Marc; Boutet-Mercey, Stéphanie; Lounifi, Imen; Godin, Béatrice; Balzergue, Sandrine; Grandjean, Olivier; Morin, Halima; Perreau, François; Debeaujon, Isabelle; Rajjou, Loïc

2014-09-01

339

Fire cue effects on seed germination of six species of northwestern Patagonian grasslands  

NASA Astrophysics Data System (ADS)

Postfire recruitment of seedlings has been attributed to a stimulation of germination by fire-related cues. The germination response to heat shock (80 °C - 5 min), smoke (60 min), the combination of both factors and no heat no smoke (control) was studied in six native species (two dominant grasses, two dominant shrubs and two annual fugitive herbs) of northwestern Patagonian grasslands. Seeds of the grasses Festuca pallescens and Stipa speciosa and the shrub Senecio bracteolatus (Asteraceae) germinated when they were exposed to heat shock, whereas seeds of the other shrub, Mulinum spinosum (Apiaceae), were killed by this fire cue. In grasses, probably the glume of caryopsis protected embryos from heat. Possibly, the seed size could explain the different responses of the two shrubs. Heat combined with smoke reduced seed germination for S. speciosa and S. bracteolatus. The heat could have scarified seeds and the longer exposure to smoke could have been toxic for embryos. The same treatment increased germination of the annual fugitive herb Boopis gracilis (Calyceraceae). We concluded that fire differentially affects the seedling recruitment of the studied species in the northwestern Patagonian grasslands.

Gonzalez, S. L.; Ghermandi, L.

2012-09-01

340

The Effect of Seed-borne Mycoflora from Sorghum and Foxtail Millet Seeds on Germination and Disease Transmission  

PubMed Central

The seed-borne mycoflora of sorghum and foxtail millet collected from different growing areas in South Korea were isolated and taxonomically identified using dry inspection, standard blotter and the agar plate method. We investigated the in vitro and in vivo germination rates of disinfected and non-disinfected seeds of sorghum and foxtail millet using sterilized and unsterilized soil. The percent recovery of seed-borne mycoflora from the seed components of sorghum and foxtail millet seeds was determined and an infection experiment using the dominant species was evaluated for seedling emergence and mortality. A higher number of seed-borne fungi was observed in sorghum compared to that of foxtail millet. Eighteen fungal genera with 34 fungal species were identified from the seeds of sorghum and 13 genera with 22 species were identified from the seeds of foxtail millet. Five dominant species such as Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme and Phoma sp. were recorded as seed-borne mycoflora in sorghum and 4 dominant species (Alternaria alternata, Aspergillus flavus, Curvularia lunata, Fusarium moniliforme) were observed in foxtail millet. The in vitro and in vivo germination rates were higher using disinfected seeds and sterilized soil. More seed-borne fungi were recovered from the pericarp compared to the endosperm and seed embryo. The percent recovery of seed-borne fungi ranged from 2.22% to 60.0%, and Alternaria alternata, Curvularia lunata and 4 species of Fusarium were isolated from the endosperm and embryo of sorghum and foxtail millet. Inoculation of the dominant seed-borne fungi showed considerable mortality of seedlings. All the transmitted seed-borne fungi might well be a primary source of infection of sorghum and foxtail millet crops. PMID:22783105

Yago, Jonar I.; Bae, Soon-do; Yoon, Young-Nam; Kim, Hyun-Ju; Nam, Min-hee

2011-01-01

341

Overexpression of Nelumbo nucifera metallothioneins 2a and 3 enhances seed germination vigor in Arabidopsis.  

PubMed

Metallothioneins (MTs) are small, cysteine-rich and metal-binding proteins which are involved in metal homeostasis and scavenging of reactive oxygen species. Although plant MTs have been intensively studied, their roles in seeds remain to be clearly established. Here, we report the isolation and characterization of NnMT2a, NnMT2b and NnMT3 from sacred lotus (Nelumbo nucifera Gaertn.) and their roles in seed germination vigor. The transcripts of NnMT2a, NnMT2b and NnMT3 were highly expressed in developing and germinating sacred lotus seeds, and were dramatically up-regulated in response to high salinity, oxidative stresses and heavy metals. Analysis of transformed Arabidopsis protoplasts showed that NnMT2a-YFP and NnMT3-YFP were localized in cytoplasm and nucleoplasm. Transgenic Arabidopsis seeds overexpressing NnMT2a and NnMT3 displayed improved resistance to accelerated aging (AA) treatment, indicating their significant roles in seed germination vigor. These transgenic seeds also exhibited higher superoxide dismutase activity compared to wild-type seeds after AA treatment. In addition, we showed that NnMT2a and NnMT3 conferred improved germination ability to NaCl and methyl viologen on transgenic Arabidopsis seeds. Taken together, these data demonstrate that overexpression of NnMT2a and NnMT3 in Arabidopsis significantly enhances seed germination vigor after AA treatment and under abiotic stresses. PMID:21971996

Zhou, Yuliang; Chu, Pu; Chen, Huhui; Li, Yin; Liu, Jun; Ding, Yu; Tsang, Edward W T; Jiang, Liwen; Wu, Keqiang; Huang, Shangzhi

2012-03-01

342

Climate warming could shift the timing of seed germination in alpine plants  

PubMed Central

Background and Aims Despite the considerable number of studies on the impacts of climate change on alpine plants, there have been few attempts to investigate its effect on regeneration. Recruitment from seeds is a key event in the life-history of plants, affecting their spread and evolution and seasonal changes in climate will inevitably affect recruitment success. Here, an investigation was made of how climate change will affect the timing and the level of germination in eight alpine species of the glacier foreland. Methods Using a novel approach which considered the altitudinal variation of temperature as a surrogate for future climate scenarios, seeds were exposed to 12 different cycles of simulated seasonal temperatures in the laboratory, derived from measurements at the soil surface at the study site. Key Results Under present climatic conditions, germination occurred in spring, in all but one species, after seeds had experienced autumn and winter seasons. However, autumn warming resulted in a significant increase in germination in all but two species. In contrast, seed germination was less sensitive to changes in spring and/or winter temperatures, which affected only three species. Conclusions Climate warming will lead to a shift from spring to autumn emergence but the extent of this change across species will be driven by seed dormancy status. Ungerminated seeds at the end of autumn will be exposed to shorter winter seasons and lower spring temperatures in a future, warmer climate, but these changes will only have a minor impact on germination. The extent to which climate change will be detrimental to regeneration from seed is less likely to be due to a significant negative effect on germination per se, but rather to seedling emergence in seasons that the species are not adapted to experience. Emergence in autumn could have major implications for species currently adapted to emerge in spring. PMID:22596094

Mondoni, Andrea; Rossi, Graziano; Orsenigo, Simone; Probert, Robin J.

2012-01-01

343

Demethylesterification of cell wall pectins in Arabidopsis plays a role in seed germination.  

PubMed

The methylesterification status of cell wall homogalacturonans, mediated through the action of pectin methylesterases (PMEs), influences the biophysical properties of plant cell walls such as elasticity and porosity, important parameters for cell elongation and water uptake. The completion of seed germination requires cell wall extensibility changes in both the radicle itself and in the micropylar tissues surrounding the radicle. In wild-type seeds of Arabidopsis (Arabidopsis thaliana), PME activities peaked around the time of testa rupture but declined just before the completion of germination (endosperm weakening and rupture). We overexpressed an Arabidopsis PME inhibitor to investigate PME involvement in seed germination. Seeds of the resultant lines showed a denser methylesterification status of their cell wall homogalacturonans, but there were no changes in the neutral sugar and uronic acid composition of the cell walls. As compared with wild-type seeds, the PME activities of the overexpressing lines were greatly reduced throughout germination, and the low steady-state levels neither increased nor decreased. The most striking phenotype was a significantly faster rate of germination, which was not connected to altered testa rupture morphology but to alterations of the micropylar endosperm cells, evident by environmental scanning electron microscopy. The transgenic seeds also exhibited an apparent reduced sensitivity to abscisic acid with respect to its inhibitory effects on germination. We speculate that PME activity contributes to the temporal regulation of radicle emergence in endospermic seeds by altering the mechanical properties of the cell walls and thereby the balance between the two opposing forces of radicle elongation and mechanical resistance of the endosperm. PMID:23129203

Müller, Kerstin; Levesque-Tremblay, Gabriel; Bartels, Sebastian; Weitbrecht, Karin; Wormit, Alexandra; Usadel, Bjoern; Haughn, George; Kermode, Allison R

2013-01-01

344

Endogenous gibberellins and kauranoids identified from developing and germinating barley grain  

Microsoft Academic Search

Several gibberellins (GAs) and kauranoids were identified in extracts of barley (Hordeum vulgare) by combined capillary gas chromatography-mass spectrometry (GC-MS). A partially purified acidic ethyl acetate extract from\\u000a 21-day postanthesis developing barley grain (cv. Proctor) contained GA1 (trace), GA4 (trace), GA8 (trace), GA12, GA17, GA20 (tentative) (trace), GA25, GA34, GA48, 18-hydroxy-GA4, 12?-hydroxy-GA9, and 18-hydroxy-GA34 (tentative). A hydrolyzed butanol extract contained

Paul Gaskin; Sarah Jane Gilmour; John R. Lenton; Jake MacMillan; Valerie M. Sponsel

1983-01-01

345

OsLOX2, a rice type I lipoxygenase, confers opposite effects on seed germination and longevity.  

PubMed

Rice production and seed storage are confronted with grain deterioration and loss of seed viability. Some members of the lipoxygenase (LOX) family function in degradation of storage lipids during the seed germination, but little is known about their influence on seed longevity during storage. We characterized the role of rice OsLOX2 gene in seed germination and longevity via over-expression and knock-down approaches. Abundant expression of OsLOX2 was detected in panicles, roots, and stems, but not in leaves. Moreover, OsLOX2 was highly induced during germination. OsLOX2 protein, located in the cytoplasm, showed a wide range of temperature adaptation (20-50 °C) and a substrate preference to linoleic acid. Lines over-expressing OsLOX2 showed accelerated seed germination under normal condition and lower seed viability after accelerated aging. RNA interference (RNAi) of OsLOX2 caused delayed germination and enhanced seed longevity. RNAi lines with strongly repressed OsLOX2 activity completely lost the capability of germination after accelerated aging. More lipid hydroperoxide were found in OE15 than the control, but less in RNAi lines than in the WT Nipponbare. Therefore, OsLOX2 acts in opposite directions during seed germination and longevity during storage. Appropriate repression of the OsLOX2 gene may delay the aging process during the storage without compromising germination under normal conditions. PMID:24792034

Huang, Jiexue; Cai, Maohong; Long, Qizhang; Liu, Linglong; Lin, Qiuyun; Jiang, Ling; Chen, Saihua; Wan, Jianmin

2014-08-01

346

Strategies of seed dispersal and germination in plants inhabiting deserts  

Microsoft Academic Search

Massive seed consumption is typical in many deserts. The “escape” or “protection” strategies of seed dispersal are important, as they prevent massive seed consumption. The more extreme the desert, the more unpredictable the low amounts and distribution of the rains as well as the beginning and length of the season or seasons with rains. Seeds, which have the highest resistance

Yitzchak Gutterman; Jacob Blaustein

1994-01-01

347

Arabidopsis Cytokinin Receptor Mutants Reveal Functions in Shoot Growth, Leaf Senescence, Seed Size, Germination, Root Development, and Cytokinin Metabolism  

Microsoft Academic Search

We used loss-of-function mutants to study three Arabidopsis thaliana sensor histidine kinases, AHK2, AHK3, and CRE1\\/ AHK4, known to be cytokinin receptors. Mutant seeds had more rapid germination, reduced requirement for light, and decreased far-red light sensitivity, unraveling cytokinin functions in seed germination control. Triple mutant seeds were more than twice as large as wild-type seeds. Genetic analysis indicated a

Michael Riefler; Ondrej Novak; Miroslav Strnad; Thomas Schmullinga

2006-01-01

348

Germination of Dimorphic Seeds of the Desert Annual Halophyte Suaeda aralocaspica (Chenopodiaceae), a C4 Plant without Kranz Anatomy  

PubMed Central

Background and Aims Suaeda aralocaspica is a C4 summer annual halophyte without Kranz anatomy that is restricted to the deserts of central Asia. It produces two distinct types of seeds that differ in colour, shape and size. The primary aims of the present study were to compare the dormancy and germination characteristics of dimorphic seeds of S. aralocaspica and to develop a conceptual model of their dynamics. Methods Temperatures simulating those in the natural habitat of S. aralocaspica were used to test for primary dormancy and germination behaviour of fresh brown and black seeds. The effects of cold stratification, gibberellic acid, seed coat scarification, seed coat removal and dry storage on dormancy breaking were tested in black seeds. Germination percentage and recovery responses of brown seeds, non-treated black seeds and 8-week cold-stratified black seeds to salt stress were tested. Key Results Brown seeds were non-dormant, whereas black seeds had non-deep Type 2 physiological dormancy (PD). Germination percentage and rate of germination of brown seeds and of variously pretreated black seeds were significantly higher than those of non-pretreated black seeds. Exposure of seeds to various salinities had significant effects on germination, germination recovery and induction into secondary dormancy. A conceptual model is presented that ties these results together and puts them into an ecological context. Conclusions The two seed morphs of S. aralocaspica exhibit distinct differences in dormancy and germination characteristics. Suaeda aralocaspica is the first cold desert halophyte for which non-deep Type 2 PD has been documented. PMID:18772148

Wang, Lei; Huang, Zhenying; Baskin, Carol C.; Baskin, Jerry M.; Dong, Ming

2008-01-01

349

Interaction of light and temperature on seed germination of Rumex obtusifolius L  

Microsoft Academic Search

Germination of Rumex obtusifolius L. seeds (nutlets) is low in darkness at 25° C. Germination is stimulated by exposure to 10 min red light (R) and also by a 10-min elevation of temperature to 35° C. A 10-min exposure to far-red light (FR) can reverse the effect of both R (indicating phytochrome control) and 35° C treatment. Fluence-response curves for

David J. Hand; Gillian Craig; Massanori Takaki; Richard E. Kendrick

1982-01-01

350

Seed germination and salinity tolerance in plant species growing on saline wastelands  

Microsoft Academic Search

Seven plant species including three chenopods:Suaeda fruticosa, Kochia indica, Atriplex crassifolia and four grasses:Sporobolus arabicus, Cynodon dactylon, Polypogon monspeliensis, Desmostachya bipinnata, varied greatly in their seed germination and growth responses to soil moisture or salinity. The germination percentage of\\u000a each species was significantly lower at soil moisture level of 25 % of water holding capacity than at the levels ranging

K. Mahmood; K. A. Malik; M. A. K. Lodhi; K. H. Sheikh

1996-01-01

351

Seed Germination in Relation to Salinity and Temperature in Sarcobatus Vermiculatus  

Microsoft Academic Search

Sarcobatus vermiculatus (Hook) Torrey is a leaf succulent, sodium-accumulating shrub usually found in saline substrates of the Great Basin desert, Utah, USA. Laboratory experiments were conducted to determine the effect of salinity (0, 200, 400, 600, 800 and 1000 mM NaCl) and temperature (day\\/night: 5\\/15, 10\\/20, 15\\/25, 20\\/30, and 25\\/35°C) on seed germination. S. vermiculatus showed 100% germination in non-saline

M. A. Khan; B. Gul; D. J. Weber

2002-01-01

352

Dispersal of wetland plant seeds by mallards: Influence of gut passage on recovery, retention, and germination  

Microsoft Academic Search

Seed dispersal is an important process for plants, but may be particularly important for plants occurring in spatially isolated\\u000a habitats like wetlands. Variation in the geographic distribution of wetland plant species may be strongly influenced by their\\u000a ability to use waterbirds, particularly waterfowl to enhance dispersal. We used controlled feeding and germination experiments\\u000a to investigate recovery, retention time, and germination

Chanpen Wongsriphuek; Bruce D. Dugger; Anne M. Bartuszevige

2008-01-01

353

Transcription factor AtTCP14 regulates embryonic growth potential during seed germination in Arabidopsis thaliana.  

PubMed

To understand the molecular mechanisms underlying regulation of seed germination, we searched enriched cis elements in the upstream regions of Arabidopsis genes whose transcript levels increased during seed germination. Using available published microarray data, we found that two cis elements, Up1 or Up2, which regulate outgrowth of Arabidopsis axillary shoots, were significantly over-represented. Classification of Up1- and Up2-containing genes by gene ontology revealed that protein synthesis-related genes, especially ribosomal protein genes, were highly over-represented. Expression analysis using a reporter gene driven by a synthetic promoter regulated by these elements showed that the Up1 is necessary and sufficient for germination-associated gene induction, whereas Up2 acts as an enhancer of Up1. Up1-mediated gene expression was suppressed by treatments that blocked germination. Up1 is almost identical to the site II motif, which is the predicted target of TCP transcription factors. Of 24 AtTCP genes, AtTCP14, which showed the highest transcript level just prior to germination, was functionally characterized to test its involvement in the regulation of seed germination. Transposon-tagged lines for AtTCP14 showed delayed germination. In addition, germination of attcp14 mutants exhibited hypersensitivity to exogenously applied abscisic acid and paclobutrazol, an inhibitor of gibberellin biosynthesis. AtTCP14 was predominantly expressed in the vascular tissues of the embryo, and affected gene expression in radicles in a non-cell-autonomous manner. Taken together, these results indicate that AtTCP14 regulates the activation of embryonic growth potential in Arabidopsis seeds. PMID:17953649

Tatematsu, Kiyoshi; Nakabayashi, Kazumi; Kamiya, Yuji; Nambara, Eiji

2008-01-01

354

Seeds of Brassicaceae weeds have an inherent or inducible response to the germination stimulant karrikinolide  

PubMed Central

Background and Aims Karrikinolide (KAR1) is a smoke-derived chemical that can trigger seeds to germinate. A potential application for KAR1 is for synchronizing the germination of weed seeds, thereby enhancing the efficiency of weed control efforts. Yet not all species germinate readily with KAR1, and it is not known whether seemingly non-responsive species can be induced to respond. Here a major agronomic weed family, the Brassicaceae, is used to test the hypothesis that a stimulatory response to KAR1 may be present in physiologically dormant seeds but may not be expressed under all circumstances. Methods Seeds of eight Brassicaceae weed species (Brassica tournefortii, Raphanus raphanistrum, Sisymbrium orientale, S. erysimoides, Rapistrum rugosum, Lepidium africanum, Heliophila pusilla and Carrichtera annua) were tested for their response to 1 µm KAR1 when freshly collected and following simulated and natural dormancy alleviation, which included wet–dry cycling, dry after-ripening, cold and warm stratification and a 2 year seed burial trial. Key Results Seven of the eight Brassicaceae species tested were stimulated to germinate with KAR1 when the seeds were fresh, and the remaining species became responsive to KAR1 following wet–dry cycling and dry after-ripening. Light influenced the germination response of seeds to KAR1, with the majority of species germinating better in darkness. Germination with and without KAR1 fluctuated seasonally throughout the seed burial trial. Conclusions KAR1 responses are more complex than simply stating whether a species is responsive or non-responsive; light and temperature conditions, dormancy state and seed lot all influence the sensitivity of seeds to KAR1, and a response to KAR1 can be induced. Three response types for generalizing KAR1 responses are proposed, namely inherent, inducible and undetected. Given that responses to KAR1 were either inherent or inducible in all 15 seed lots included in this study, the Brassicaceae may be an ideal target for future application of KAR1 in weed management. PMID:21821831

Long, Rowena L.; Stevens, Jason C.; Griffiths, Erin M.; Adamek, Markus; Gorecki, Marta J.; Powles, Stephen B.; Merritt, David J.

2011-01-01

355

Developmental changes in the germinability, desiccation tolerance, hardseededness, and longevity of individual seeds of Trifolium ambiguum  

PubMed Central

Background and Aims Using two parental clones of outcrossing Trifolium ambiguum as a potential model system, we examined how during seed development the maternal parent, number of seeds per pod, seed position within the pod, and pod position within the inflorescence influenced individual seed fresh weight, dry weight, water content, germinability, desiccation tolerance, hardseededness, and subsequent longevity of individual seeds. Methods Near simultaneous, manual reciprocal crosses were carried out between clonal lines for two experiments. Infructescences were harvested at intervals during seed development. Each individual seed was weighed and then used to determine dry weight or one of the physiological behaviour traits. Key Results Whilst population mass maturity was reached at 33–36 days after pollination (DAP), seed-to-seed variation in maximum seed dry weight, when it was achieved, and when maturation drying commenced, was considerable. Individual seeds acquired germinability between 14 and 44 DAP, desiccation tolerance between 30 and 40 DAP, and the capability to become hardseeded between 30 and 47 DAP. The time for viability to fall to 50 % (p50) at 60 % relative humidity and 45 °C increased between 36 and 56 DAP, when the seed coats of most individuals had become dark orange, but declined thereafter. Individual seed f. wt at harvest did not correlate with air-dry storage survival period. Analysing survival data for cohorts of seeds reduced the standard deviation of the normal distribution of seed deaths in time, but no sub-population showed complete uniformity of survival period. Conclusions Variation in individual seed behaviours within a developing population is inherent and inevitable. In this outbreeder, there is significant variation in seed longevity which appears dependent on embryo genotype with little effect of maternal genotype or architectural factors. PMID:20228084

Hay, F. R.; Smith, R. D.; Ellis, R. H.; Butler, L. H.

2010-01-01

356

Reactive oxygen species, abscisic acid and ethylene interact to regulate sunflower seed germination.  

PubMed

Sunflower (Helianthus annuus?L.) seed dormancy is regulated by reactive oxygen species (ROS) and can be alleviated by incubating dormant embryos in the presence of methylviologen (MV), a ROS-generating compound. Ethylene alleviates sunflower seed dormancy whereas abscisic acid (ABA) represses germination. The purposes of this study were to identify the molecular basis of ROS effect on seed germination and to investigate their possible relationship with hormone signalling pathways. Ethylene treatment provoked ROS generation in embryonic axis whereas ABA had no effect on their production. The beneficial effect of ethylene on germination was lowered in the presence of antioxidant compounds, and MV suppressed the inhibitory effect of ABA. MV treatment did not alter significantly ethylene nor ABA production during seed imbibition. Microarray analysis showed that MV treatment triggered differential expression of 120 probe sets (59 more abundant and 61 less abundant genes), and most of the identified transcripts were related to cell signalling components. Many transcripts less represented in MV-treated seeds were involved in ABA signalling, thus suggesting an interaction between ROS and ABA signalling pathways at the transcriptional level. Altogether, these results shed new light on the crosstalk between ROS and plant hormones in seed germination. PMID:24811898

El-Maarouf-Bouteau, Hayat; Sajjad, Yasar; Bazin, Jérémie; Langlade, Nicolas; Cristescu, Simona M; Balzergue, Sandrine; Baudouin, Emmanuel; Bailly, Christophe

2015-02-01

357

Promotion of seed germination by nitrate, nitrite, hydroxylamine, and ammonium salts.  

PubMed

Action and uptake of azides, nitrates, nitrites, hydroxylamines, and ammonium salts were measured on germination of Amaranthus albus, Lactuca sativa, Phleum pratense, Barbarea vulgaris, B. verna, and Setaria glauca seeds. Nitrate and nitrite reductase activities were measured in vivo for each of these kinds of seeds. Activities were measured in vitro for catalase, peroxidase, glycolate oxidase, and pyridine nucleotide quinone reductase on extracts of A. albus and L. sativa seeds before and after germination. The enzymic activities measured and the responsiveness of the haemproteins to inhibition by the several compounds indicate that nitrites, azides, and hydroxylamines promote seed germination by inhibition of H(2)O(2) decomposition by catalase. Ammonium salts showed pronounced promotive activity only for B. verna and B. vulgaris seeds, for which they served as metabolic substrates.The promotion of germination is thought to depend on coupling of peroxidase action to NADPH oxidation, which can regulate the pentose pathway of d-glucose 6-phosphate use. Pyridine nucleotide quinone reductase is the possible coupling enzyme. This enzyme and others required for the action are present in the seeds before imbibition of water. PMID:16658878

Hendricks, S B; Taylorson, R B

1974-09-01

358

Effects of pre-treatments and temperature on seed viability and germination of Juniperus macrocarpa Sm.  

PubMed

The effects of collecting season, collection site, laboratory pre-treatments and temperatures on seed viability and germination of Juniperus macrocarpa were investigated. Ripe cones were collected in four Sardinian dune systems, in two seasons, from plant and soil. Warm (W) and cold (C) stratifications, two combinations of them (W+C, C+W), and no pre-treatment (0) were applied. Seeds were incubated in a range of constant (10-25°C) and an alternating (25/10°C) temperature regime. Seed viability was low (ca. 40%) and varied significantly according to the collecting season. Seed germination was also low (ca. 10%), the 0 and W were the most effective pre-treatments on stimulating germination. The best germination temperature, without any pre-treatment, was 15°C (ca. 20%). J. macrocarpa seeds are dormant and the achieved results suggested that the presence of secondary dormancy is induced by cold stratification. Spring appeared to be the best season for seed collecting, whereas autumn was the best for sowing. These results give new findings for restoration activities on this species. PMID:24841961

Pinna, Maria Silvia; Mattana, Efisio; Cañadas, Eva Maria; Bacchetta, Gianluigi

2014-05-01

359

Promotion of Seed Germination by Nitrate, Nitrite, Hydroxylamine, and Ammonium Salts 1  

PubMed Central

Action and uptake of azides, nitrates, nitrites, hydroxylamines, and ammonium salts were measured on germination of Amaranthus albus, Lactuca sativa, Phleum pratense, Barbarea vulgaris, B. verna, and Setaria glauca seeds. Nitrate and nitrite reductase activities were measured in vivo for each of these kinds of seeds. Activities were measured in vitro for catalase, peroxidase, glycolate oxidase, and pyridine nucleotide quinone reductase on extracts of A. albus and L. sativa seeds before and after germination. The enzymic activities measured and the responsiveness of the haemproteins to inhibition by the several compounds indicate that nitrites, azides, and hydroxylamines promote seed germination by inhibition of H2O2 decomposition by catalase. Ammonium salts showed pronounced promotive activity only for B. verna and B. vulgaris seeds, for which they served as metabolic substrates. The promotion of germination is thought to depend on coupling of peroxidase action to NADPH oxidation, which can regulate the pentose pathway of d-glucose 6-phosphate use. Pyridine nucleotide quinone reductase is the possible coupling enzyme. This enzyme and others required for the action are present in the seeds before imbibition of water. PMID:16658878

Hendricks, S. B.; Taylorson, R. B.

1974-01-01

360

[Effect of decimeter polarized electromagnetic radiation on germinating capacity of seeds].  

PubMed

The effect of a polarization structure of electromagnetic radiation on the germinating capacity of seeds of such weeds as Green foxtail (Setaria viridis) and Green amaranth (Amaranthus retroflexus) has been studied. Seeds have been exposed to impulse electromagnetic radiation in a frequency of 896 MHz with linear, elliptical right-handed and elliptical left-handed polarizations at different power flux density levels. It is determined that the effect of the right-handed polarized electromagnetic radiation increases and the influence of the left-handed polarized one reduces the germinating capacity of seeds compared to the effect of the linearly polarized electromagnetic radiation. It is shown that the seeds have an amplitude polarization selectivity as evinced by the major effect of the right-handed polarized radiation on seeds. An electrodynamic model as the right-handed elliptically polarized antenna with the given quantity of the ellipticity of polarization is suggested to use in description of this selectivity. PMID:24455890

Polevik, N D

2013-01-01

361

Do seed mass and family affect germination and juvenile performance in Knautia arvensis? A study using failure-time methods  

NASA Astrophysics Data System (ADS)

Germination and seedling establishment are vulnerable stages in the plant life cycle. We investigated how seed mass and family (progeny origin) affect germination and juvenile performance in the grassland herb Knautia arvensis. Seeds were produced by cross-pollination by hand. The fate of 15 individually weighed seeds from each of 15 plants was followed during a 3-month growth chamber experiment. Progeny origin affected germination, both through seed mass and as an independent factor. Two groups of progenies could be distinguished by having rapid or delayed germination. The two groups had similar mean seed masses, but a positive relationship between seed mass and germination rate could be established only among the rapidly germinating progenies. These biologically relevant patterns were revealed because timing of germination was taken into account in the analyses, not only frequencies. Time-to-event data were analysed with failure-time methods, which gave more stable estimates for the relation between germination and seed mass than the commonly applied logistic regression. Progeny origin and seed mass exerted less impact on later characters like juvenile survival, juvenile biomass, and rosette number. These characters were not affected by the timing of germination under the competition-free study conditions. The decrease in the effect of progeny origin from the seed and germination to the juvenile stages suggests that parental effects other than those contributing to the offspring genotype strongly influenced the offspring phenotype at the earliest life stages. Further, the division of progeny germination patterns into two fairly distinct groups indicates that there was a genetic basis for the variation in stratification requirements among parental plants. Field studies are needed to elucidate effects of different timing of germination in the seasonal grasslands that K. arvensis inhabits.

Vange, Vibekke; Heuch, Ivar; Vandvik, Vigdis

2004-05-01

362

Control Processes in the Induction and Relief of Thermoinhibition of Lettuce Seed Germination 1  

PubMed Central

Germination of lettuce seeds (Lactuca sativa L. cv Grand Rapids) in the dark was nearly 100% at 20°C but was inhibited at 27°C and higher temperatures (thermoinhibition). A single 5-minute exposure to red light completely overcame the inhibition at temperatures up to 28°C, above which the effectiveness of single light exposures gradually declined to reach a negligible level at 32°C. However, the promotive effect of light could be extended to 34°C by repeated irradiations. At any one temperature, increased frequency of irradiations increased germination percentage, and with each degree increase in temperature, increasingly frequent irradiations were necessary to elicit maximal germination. Loss of the effectiveness of single irradiations with increase in temperature may result either from acceleration of the thermal reversion of the far red-absorbing form of phytochrome or decrease in seed sensitivity toward a given percentage of the far red-absorbing form of phytochrome. Using continuous red light to induce germination, the role of endogenous C2H4 in germination at 32°C was studied. Ethylene evolution from irradiated seeds began to increase 2 hours prior to radicle protrusion, whereas the dark-incubated (nongerminating) seeds produced a low, constant amount of C2H4 throughout the 24 hour incubation period. Inhibition of C2H4 synthesis with 2-aminoethoxyvinyl glycine and/or inhibition of C2H4 action with 2,5-norbornadiene blocked the promotive effect of light. Exogenous C2H4 overcame these blockages. The results showed that participation by endogenous C2H4 was essential for the light-induced relief of thermoinhibition of lettuce seed germination. However, light did not act exclusively via C2H4 since exogenous C2H4 alone in darkness did not promote germination. Images Figure 4 Figure 5 PMID:16666755

Saini, Hargurdeep S.; Consolacion, Evangeline D.; Bassi, Pawan K.; Spencer, Mary S.

1989-01-01

363

Effects of a warmer climate on seed germination in the subarctic  

PubMed Central

Background and Aims In a future warmer subarctic climate, the soil temperatures experienced by dispersed seeds are likely to increase during summer but may decrease during winter due to expected changes in snow depth, duration and quality. Because little is known about the dormancy-breaking and germination requirements of subarctic species, how warming may influence the timing and level of germination in these species was examined. Methods Under controlled conditions, how colder winter and warmer summer soil temperatures influenced germination was tested in 23 subarctic species. The cold stratification and warm incubation temperatures were derived from real soil temperature measurements in subarctic tundra and the temperatures were gradually changed over time to simulate different months of the year. Key Results Moderate summer warming (+2·5 °C) substantially accelerated germination in all but four species but did not affect germination percentages. Optimum germination temperatures (20/10°C) further decreased germination time and increased germination percentages in three species. Colder winter soil temperatures delayed the germination in ten species and decreased the germination percentage in four species, whereas the opposite was found in Silene acaulis. In most species, the combined effect of a reduced snow cover and summer warming resulted in earlier germination and thus a longer first growing season, which improves the chance of seedling survival. In particular the recruitment of (dwarf) shrubs (Vaccinium myrtillus, V. vitis-idaea, Betula nana), trees (Alnus incana, Betula pubescens) and grasses (Calamagrostis lapponica, C. purpurea) is likely to benefit from a warmer subarctic climate. Conclusions Seedling establishment is expected to improve in a future warmer subarctic climate, mainly by considerably earlier germination. The magnitudes of the responses are species-specific, which should be taken into account when modelling population growth and migration of subarctic species. PMID:19443459

Milbau, Ann; Graae, Bente Jessen; Shevtsova, Anna; Nijs, Ivan

2009-01-01

364

Protein Synthesis in Embryos of Dormant and Germinating Agrostemma githago L. seeds.  

PubMed

The time course of protein synthesis in embryos of dormant and afterripened Agrostemma githago seeds was studied. In embryos of afterripened geminating seeds, protein synthesis increased in three successive stages: (a) concurrent with swelling; (b) during the lag phase between the completion of water uptake and the onset of growth; and (c) immediately after protrusion through the seed coat. Embryos of dormant seeds showed the first increase but not the second unless dormancy was broken by imbibition at 4 degrees C. This indicates that dormancy affects processes prior to the onset of growth. The third increase was largely due to higher oxygen availability after the rupture of the seed coat and not to actual growth. It could also be elicited in dormant embryos by isolating them from the seeds.Electrophoretic analysis of the newly synthesized proteins demonstrated that the patterns of dormant and afterripened embryos became significantly different in both axes and cotyledons only just prior to the onset of axis elongation. Thereafter, the differences became larger.When afterripened or dormant seeds were transferred from a low, germination-permitting to a high, germination-inhibiting temperature, the seeds germinated at the high temperature if they had completed the lag phase to a sufficient extent at the low temperature. This shows that the processes during the lag phase were inhibited by the high temperature while the onset of growth was not affected. PMID:16663762

de Klerk, G J; Smulders, R

1984-08-01

365

Protein Synthesis in Embryos of Dormant and Germinating Agrostemma githago L. seeds  

PubMed Central

The time course of protein synthesis in embryos of dormant and afterripened Agrostemma githago seeds was studied. In embryos of afterripened geminating seeds, protein synthesis increased in three successive stages: (a) concurrent with swelling; (b) during the lag phase between the completion of water uptake and the onset of growth; and (c) immediately after protrusion through the seed coat. Embryos of dormant seeds showed the first increase but not the second unless dormancy was broken by imbibition at 4°C. This indicates that dormancy affects processes prior to the onset of growth. The third increase was largely due to higher oxygen availability after the rupture of the seed coat and not to actual growth. It could also be elicited in dormant embryos by isolating them from the seeds. Electrophoretic analysis of the newly synthesized proteins demonstrated that the patterns of dormant and afterripened embryos became significantly different in both axes and cotyledons only just prior to the onset of axis elongation. Thereafter, the differences became larger. When afterripened or dormant seeds were transferred from a low, germination-permitting to a high, germination-inhibiting temperature, the seeds germinated at the high temperature if they had completed the lag phase to a sufficient extent at the low temperature. This shows that the processes during the lag phase were inhibited by the high temperature while the onset of growth was not affected. PMID:16663762

de Klerk, Geert Jan; Smulders, René

1984-01-01

366

Effects of cold plasma treatment on seed germination and seedling growth of soybean  

PubMed Central

Effects of cold plasma treatment on soybean (Glycine max L. Merr cv. Zhongdou 40) seed germination and seedling growth were studied. Seeds were pre-treated with 0, 60, 80, 100 and 120?W of cold plasma for 15?s. Results showed that plasma treatments had positive effects on seed germination and seedling growth, and treatment of 80?W had the highest stimulatory effect. Germination and vigor indices significantly increased by 14.66% and 63.33%, respectively. Seed's water uptake improved by 14.03%, and apparent contact angle decreased by 26.19%. Characteristics of seedling growth, including shoot length, shoot dry weight, root length and root dry weight, significantly increased by 13.77%, 21.95%, 21.42% and 27.51%, respectively, compared with control. The seed reserve utilization, including weight of the mobilized seed reserve, seed reserve depletion percentage and seed reserve utilization efficiency significantly improved by cold plasma treatment. In addition, soluble sugar and protein contents were 16.51% and 25.08% higher than those of the control. Compared to a 21.95% increase in shoot weight, the root weight increased by 27.51% after treatment, indicating that plasma treatment had a greater stimulatory effect on plant roots. These results indicated that cold plasma treatment might promote the growth even yield of soybean. PMID:25080862

Ling, Li; Jiafeng, Jiang; Jiangang, Li; Minchong, Shen; Xin, He; Hanliang, Shao; Yuanhua, Dong

2014-01-01

367

Effects of cold plasma treatment on seed germination and seedling growth of soybean  

NASA Astrophysics Data System (ADS)

Effects of cold plasma treatment on soybean (Glycine max L. Merr cv. Zhongdou 40) seed germination and seedling growth were studied. Seeds were pre-treated with 0, 60, 80, 100 and 120 W of cold plasma for 15 s. Results showed that plasma treatments had positive effects on seed germination and seedling growth, and treatment of 80 W had the highest stimulatory effect. Germination and vigor indices significantly increased by 14.66% and 63.33%, respectively. Seed's water uptake improved by 14.03%, and apparent contact angle decreased by 26.19%. Characteristics of seedling growth, including shoot length, shoot dry weight, root length and root dry weight, significantly increased by 13.77%, 21.95%, 21.42% and 27.51%, respectively, compared with control. The seed reserve utilization, including weight of the mobilized seed reserve, seed reserve depletion percentage and seed reserve utilization efficiency significantly improved by cold plasma treatment. In addition, soluble sugar and protein contents were 16.51% and 25.08% higher than those of the control. Compared to a 21.95% increase in shoot weight, the root weight increased by 27.51% after treatment, indicating that plasma treatment had a greater stimulatory effect on plant roots. These results indicated that cold plasma treatment might promote the growth even yield of soybean.

Ling, Li; Jiafeng, Jiang; Jiangang, Li; Minchong, Shen; Xin, He; Hanliang, Shao; Yuanhua, Dong

2014-07-01

368

Effects of cold plasma treatment on seed germination and seedling growth of soybean.  

PubMed

Effects of cold plasma treatment on soybean (Glycine max L. Merr cv. Zhongdou 40) seed germination and seedling growth were studied. Seeds were pre-treated with 0, 60, 80, 100 and 120 W of cold plasma for 15 s. Results showed that plasma treatments had positive effects on seed germination and seedling growth, and treatment of 80 W had the highest stimulatory effect. Germination and vigor indices significantly increased by 14.66% and 63.33%, respectively. Seed's water uptake improved by 14.03%, and apparent contact angle decreased by 26.19%. Characteristics of seedling growth, including shoot length, shoot dry weight, root length and root dry weight, significantly increased by 13.77%, 21.95%, 21.42% and 27.51%, respectively, compared with control. The seed reserve utilization, including weight of the mobilized seed reserve, seed reserve depletion percentage and seed reserve utilization efficiency significantly improved by cold plasma treatment. In addition, soluble sugar and protein contents were 16.51% and 25.08% higher than those of the control. Compared to a 21.95% increase in shoot weight, the root weight increased by 27.51% after treatment, indicating that plasma treatment had a greater stimulatory effect on plant roots. These results indicated that cold plasma treatment might promote the growth even yield of soybean. PMID:25080862

Ling, Li; Jiafeng, Jiang; Jiangang, Li; Minchong, Shen; Xin, He; Hanliang, Shao; Yuanhua, Dong

2014-01-01

369

In vitro seed germination of economically important edible bamboo Dendrocalamus membranaceus Munro.  

PubMed

An in vitro propagation protocol using mature seeds of D. membranaceus was successfully established. Scarcity of seeds in bamboos because of their long flowering periods and irregular seed set resulting in low viability and germination potential, motivated us to undertake the present study. The effects of sterilants, light conditions, exogenous application of plant growth regulators and temperature in overcoming germination barriers in ageing seeds of bamboo were studied. It was found that HgCl2 (0.1%) along with bleach (15%) was more effective in raising aseptic cultures. Dark conditions, high temperatures around 30 degrees C and soaking of seeds in GA3 solution (50 ppm) overnight stimulated high percent of seed germination with corresponding increase in shoot length (2.7 +/- 0.7 mm) and number of sprouts (2.1 +/- 0.7) per explants during culture initiation. 6-benzylaminopurine acted synergistically with kinetin to give optimum germination rate of 70 +/- 13.9% as compared to 63.13% when used individually. For prolonged maintenance of cultures, 2% sucrose was found to be suitable for promoting photomixotrophic micropropagation. Following this procedure, about 65% survival of plantlets could be achieved during hardening. Biochemically seeds consume starchy endosperm for emergence of radicle which is taken as a sign of germination as also evident from the present study. Loss of viability and vigour after a year was confirmed by Tetrazolium chloride test. Micropropagation protocol developed here will ensure regeneration of large number of plants in a relatively short time. Conclusively, in vitro propagation protocol developed in D. membranaceus using mature seeds as an explants is reported for the first time. PMID:23441484

Brar, Jasmine; Anand, Manju; Sood, Anil

2013-01-01

370

of the exposed germ, which may reduce germination and emergence. Yields of current hulless barley lines  

E-print Network

and become to- tally separated when the grain is combined. The grain of hulless barley looks more like wheat Tech Mark M. Alley, W.G. Wysor Professor of Agriculture and Soil Fertility Specialist, Virginia Tech Steve B. Phillips, Associate Professor and Soil Fertility Specialist, Eastern Shore AREC E. Scott Hagood

Liskiewicz, Maciej

371

PHYSIOLOGY AND BIO – CHEMISTRY OF GERMINATION OF DIFFERENT TYPES OF SEEDS – V PROTEIN AND SUGAR CONTENTS OF SEEDS UNDER THE INFLUENCE OF DIFFERENT SPECTRAL BANDS OF LIGHT  

PubMed Central

The estimation of total protein and total sugars of cucumber, mango, paddy, radish and tomato seeds in dry, wet and germinating conditions were studied. Also the results are discussed in the light of possible physiological and bio – chemical change taking place inside the seeds during the process of absorption and germination. PMID:22557525

Majumder, A. K.; Boissya, C. L.

1986-01-01

372

The role of nitric oxide in the germination of plant seeds and pollen.  

PubMed

Two complex physiological processes, with opposite positions in the plant's life-cycle, seed and pollen germination, are vital to the accomplishment of successful plant growth and reproduction. This review summarizes the current state of knowledge of the intersection of NO signalling with the signalling pathways of ABA, GA, and ethylene; plant hormones that control the release of plant seeds from dormancy and germination. The cross-talk of NO and ROS is involved in the light- and hormone-specific regulation of seeds' developmental processes during the initiation of plant ontogenesis. Similarly to seed germination, the mechanisms of plant pollen hydration, germination, tube growth, as well as pollen-stigma recognition are tightly linked to the proper adjustment of NO and ROS levels. The interaction of NO with ROS and secondary messengers such as Ca(2+), cAMP and cGMP discovered in pollen represent a common mechanism of NO signalling. The involvement of NO in both breakpoints of plant physiology, as well as in the germination of spores within fungi and oomycetes, points toward NO as a component of an evolutionary conserved signalling pathway. PMID:21893253

Šírová, Jana; Sedlá?ová, Michaela; Piterková, Jana; Luhová, Lenka; Pet?ivalský, Marek

2011-11-01

373

Inhibition of germination of dormant barley (Hordeum vulgare L.) grains by blue light as related to oxygen and hormonal regulation.  

PubMed

Germination of primary dormant barley grains is promoted by darkness and temperatures below 20?°C, but is strongly inhibited by blue light. Exposure under blue light at 10?°C for periods longer than five days, results in a progressive inability to germinate in the dark, considered as secondary dormancy. We demonstrate that the inhibitory effect of blue light is reinforced in hypoxia. The inhibitory effect of blue light is associated with an increase in embryo abscisic acid (ABA) content (by 3.5- to 3.8-fold) and embryo sensitivity to both ABA and hypoxia. Analysis of expression of ABA metabolism genes shows that increase in ABA mainly results in a strong increase in HvNCED1 and HvNCED2 expression, and a slight decrease in HvABA8'OH-1. Among the gibberellins (GA) metabolism genes examined, blue light decreases the expression of HvGA3ox2, involved in GA synthesis, increases that of GA2ox3 and GA2ox5, involved in GA catabolism, and reduces the GA signalling evaluated by the HvExpA11 expression. Expression of secondary dormancy is associated with maintenance of high embryo ABA content and a low HvExpA11 expression. The partial reversion of the inhibitory effect of blue light by green light also suggests that cryptochrome might be involved in this hormonal regulation. PMID:24256416

Hoang, Hai Ha; Sechet, Julien; Bailly, Christophe; Leymarie, Juliette; Corbineau, Françoise

2014-06-01

374

Seed germination ecology of Polymnia canadensis (Asteraceae), a monocarpic species of the North American Temperate Deciduous Forest  

Microsoft Academic Search

The seed germination of Polymnia canadensis was studied in relation to its wide variation in life history and its ecology as a mostly facultative biennial, a life cycle type that is rare in stable forest habitats in eastern North America. The seed dormancy and germination characteristics of P. canadensis were like some other herbaceous woodland species of diverse life cycle

Martin H. Bender; Jerry M. Baskin; Carol C. Baskin

2003-01-01

375

G. Leubner-Metzger et al.: -1,3-Glucanase and tobacco seed germination Planta (1996) 199: 282-288  

E-print Network

G. Leubner-Metzger et al.: �-1,3-Glucanase and tobacco seed germination - 1 - Planta (1996) 199,3-glucanase induction in tobacco seed germination Gerhard Leubner-Metzger, Corinne Fründt, Frederick Meins, Jr.g. 10-5 M GA4 or GA7) can substitute for light in releasing dormancy. Measurements of �-1,3-glucanase

Leubner, Gerhard

376

Effects of wastewater from olive processing on seed germination and early plant growth of different vegetable species  

Microsoft Academic Search

The effects of wastewater from olive processing on seed germination and early plant growth of different vegetable species were examined. Three types of wastewater at different concentrations were tested: raw wastewater, wastewater with organic matter removed and deionized wastewater.Results generally indicate an inhibitory effect on seed germination and early plant growth by all treatments containing any kind of wastewater. Of

J. D. Perez; E. Esteban; M. Gomez

1986-01-01

377

EFFECT OF COMPATIBLE OSMOTICA AND PLANT GROWTH REGULATORS IN ALLEVIATING SALINITY STRESS ON THE SEED GERMINATION OF ALLENROLFEA OCCIDENTALIS  

Microsoft Academic Search

Allenrolfea occidentalis, a perennial halophytic shrub in the family Chenopodiaceae is widely distributed in the inland salt marshes and salt playas of western United States. Experiments were conducted to determine the influence of compatible osmotica (betaine and proline) and growth regulators (gibberellic acid and kinetin) in alleviating salinity stress on the seed germination of A. occidentalis. Seed germination decreased with

BILQUEES GUL; M. AJMAL KHAN

2008-01-01

378

The ecophysiology of seed persistence: a mechanistic view of the journey to germination or demise.  

PubMed

Seed persistence is the survival of seeds in the environment once they have reached maturity. Seed persistence allows a species, population or genotype to survive long after the death of parent plants, thus distributing genetic diversity through time. The ability to predict seed persistence accurately is critical to inform long-term weed management and flora rehabilitation programs, as well as to allow a greater understanding of plant community dynamics. Indeed, each of the 420000 seed-bearing plant species has a unique set of seed characteristics that determine its propensity to develop a persistent soil seed bank. The duration of seed persistence varies among species and populations, and depends on the physical and physiological characteristics of seeds and how they are affected by the biotic and abiotic environment. An integrated understanding of the ecophysiological mechanisms of seed persistence is essential if we are to improve our ability to predict how long seeds can survive in soils, both now and under future climatic conditions. In this review we present an holistic overview of the seed, species, climate, soil, and other site factors that contribute mechanistically to seed persistence, incorporating physiological, biochemical and ecological perspectives. We focus on current knowledge of the seed and species traits that influence seed longevity under ex situ controlled storage conditions, and explore how this inherent longevity is moderated by changeable biotic and abiotic conditions in situ, both before and after seeds are dispersed. We argue that the persistence of a given seed population in any environment depends on its resistance to exiting the seed bank via germination or death, and on its exposure to environmental conditions that are conducive to those fates. By synthesising knowledge of how the environment affects seeds to determine when and how they leave the soil seed bank into a resistance-exposure model, we provide a new framework for developing experimental and modelling approaches to predict how long seeds will persist in a range of environments. PMID:24618017

Long, Rowena L; Gorecki, Marta J; Renton, Michael; Scott, John K; Colville, Louise; Goggin, Danica E; Commander, Lucy E; Westcott, David A; Cherry, Hillary; Finch-Savage, William E

2015-02-01

379

Genotyping of Endosperms To Determine Seed Dormancy Genes Regulating Germination Through Embryonic, Endospermic or Maternal Tissues in Rice.  

PubMed

Seed dormancy is imposed by one or more of the embryo, endosperm and maternal tissues that belong to two generations and represent two ploidy levels. Many quantitative trait loci (QTL) have been identified for seed dormancy as measured by gross effects on reduced germination rate or delayed germination in crop or model plants. This research developed an endosperm genotype-based genetic approach to determine specific tissues through which a mapped QTL regulates germination using rice as a model. This approach involves testing germination velocity for partially after-ripened seeds harvested from single plants heterozygous for a tested QTL and genotyping endosperms from individual germinated and non-germinated seeds with a co-dominant DNA marker located on the QTL peak region. Information collected about the QTL includes genotypic frequencies in germinated and/or non-germinated subpopulations; allelic frequency distributions during a germination period; endosperm or embryo genotypic differences in germination velocity; and genotypic frequencies for gametes involved in the double fertilization to form the sampled seeds. Using this approach, the seed dormancy loci SD12, SD1-2, and SD7-1 were determined to regulate germination through the embryo, endosperm and maternal tissues, respectively; SD12 and SD1-2 acted additively on germination velocity in the offspring tissues; and SD12 was also associated with the preferential fertilization of male gametes in rice. This new genetic approach can be used to characterize mapped genes/QTL for tissue-specific functions in endospermic seeds and for marker-assisted selection of QTL alleles before or immediately after germination in crop breeding. PMID:25480961

Gu, Xing-You; Zhang, Jinfeng; Ye, Heng; Zhang, Lihua; Feng, Jiuhuan

2014-12-01

380

Effects of phthalate ester treatment on seed germination and antioxidant enzyme activities of Phaseolus radiatus L.  

PubMed

Effects of di-(2-ethylhexyl) phthalate and di-n-butyl phthalate on seed germination rate and antioxidant enzymes activities of mung bean (Phaseolus radiatus L.) were investigated. Results showed that under the treatment with 10 mg/kg of phthalate esters (PAEs), superoxide dismutase (SOD), peroxidase and catalase (CAT) activities were higher than those of the control (p > 0.05). But SOD and CAT activities decreased with the PAEs concentrations and the treatment duration, and were significantly lower than those of the control (p < 0.05). Effect of PAEs stress on SOD activity in germinating seeds of mung bean displayed a significant dose-effect relationship. PMID:24535285

Liu, Wenli; Zhang, Chongbang; Liu, Shuyuan

2014-05-01

381

Tolerance and recovery responses of playa halophytes to light, salinity and temperature stresses during seed germination  

Microsoft Academic Search

Halogeton glomeratus (M. Bieb.) C.A. Mey., Lepidium latifolium Linn. and Peganum harmala Linn. are distributed in temperate salt playa habitats of Upper Hunza, Pakistan. Seeds were germinated under various salinity (0–500mM NaCl), light (12h-light:12h-dark and 24h-dark) and temperature (5\\/15, 10\\/20, 15\\/25, 20\\/30, and 25\\/35°C, dark\\/light) regimes for 20 days to determine the optimal conditions for germination and recovery of seeds

M. Zaheer Ahmed; M. Ajmal Khan

2010-01-01

382

DELAY OF GERMINATION 1 mediates a conserved coat-dormancy mechanism for the temperature- and gibberellin-dependent control of seed germination  

PubMed Central

Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the DELAY OF GERMINATION 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapping experiments between Brassicaceae species we show that the DOG1-mediated dormancy mechanism is conserved. Biomechanical analyses show that this mechanism regulates the material properties of the endosperm, a seed tissue layer acting as germination barrier to control coat dormancy. We found that DOG1 inhibits the expression of gibberellin (GA)-regulated genes encoding cell-wall remodeling proteins in a temperature-dependent manner. Furthermore we demonstrate that DOG1 causes temperature-dependent alterations in the seed GA metabolism. These alterations in hormone metabolism are brought about by the temperature-dependent differential expression of genes encoding key enzymes of the GA biosynthetic pathway. These effects of DOG1 lead to a temperature-dependent control of endosperm weakening and determine the optimal temperature for germination. The conserved DOG1-mediated coat-dormancy mechanism provides a highly adaptable temperature-sensing mechanism to control the timing of germination. PMID:25114251

Graeber, Kai; Linkies, Ada; Steinbrecher, Tina; Mummenhoff, Klaus; Tarkowská, Danuše; Ture?ková, Veronika; Ignatz, Michael; Sperber, Katja; Voegele, Antje; de Jong, Hans; Urbanová, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard

2014-01-01

383

Proteomic and functional analyses of Nelumbo nucifera annexins involved in seed thermotolerance and germination vigor.  

PubMed

Annexins are multifunctional proteins characterized by their capacity to bind calcium ions and negatively charged lipids. Although there is increasing evidence implicating their importance in plant stress responses, their functions in seeds remain to be further studied. In this study, we identified a heat-induced annexin, NnANN1, from the embryonic axes of sacred lotus (Nelumbo nucifera Gaertn.) using comparative proteomics approach. Moreover, the expression of NnANN1 increased considerably in response to high-temperature treatment. Quantitative real-time PCR (qRT-PCR) revealed that the transcripts of NnANN1 were detected predominantly during seed development and germination in sacred lotus, implicating a role for NnANN1 in plant seeds. Ectopic expression of NnANN1 in Arabidopsis resulted in enhanced tolerance to heat stress in transgenic seeds. In addition, compared to the wild-type seeds, transgenic seeds ectopically expressing NnANN1 exhibited improved resistance to accelerated aging treatment used for assessing seed vigor. Furthermore, transgenic seeds showed enhanced peroxidase activities, accompanied with reduced lipid peroxidation and reduced ROS release levels compared to the wild-type seeds. Taken together, these results indicate that NnANN1 plays an important role in seed thermotolerance and germination vigor. PMID:22167260

Chu, Pu; Chen, Huhui; Zhou, Yuliang; Li, Yin; Ding, Yu; Jiang, Liwen; Tsang, Edward W T; Wu, Keqiang; Huang, Shangzhi

2012-06-01

384

Optimal germination condition by sulfuric acid pretreatment to improve seed germination of Sabina vulgaris Ant  

Microsoft Academic Search

Understanding the germination traits of plants is important not only for understanding natural regeneration processes but\\u000a also for developing seedling production techniques for planting. Sabina vulgaris Ant. is a common species used for reforestation in semi-arid areas of the Mu-Us Desert, in Inner Mongolia, China, but its\\u000a extremely low germination rate, both in situ and in vivo, is a bottleneck

Ayumi Tanaka-Oda; Tanaka Kenzo; Kenji Fukuda

2009-01-01

385

Seeds may be started in peat pots; they are slow to germinate (up to three weeks indoors),  

E-print Network

Seeds may be started in peat pots; they are slow to germinate (up to three weeks indoors), so; it is considered very hardy. Start asparagus either from seed or from 1- to 2-year-old crowns. For fastest results dealers'asparagus. Starting plants from seed requires an extra year before harvest. Seed may be started

Liskiewicz, Maciej

386

Strategies for Adaptation of Suaeda physophora, Haloxylon ammodendron and Haloxylon persicum to a Saline Environment During Seed-Germination Stage  

PubMed Central

• Background and Aims Germination is very important for plant establishment in arid regions. The strategies taken by halophytes during the seed germination stage to adapt to saline environments in an arid zone were investigated in Suaeda physophora (euhalophyte), Haloxylon ammodendron (xero-halophyte) and Haloxylon persicum (xerophyte). • Methods Seeds of S. physophora, H. ammodendron and H. persicum were exposed to a range of iso-osmotic NaCl and PEG solutions. Seed germination in, and recovery germination from, high NaCl were recorded. The effects of iso-osmotic NaCl and PEG on seed water uptake and changes in ion content were measured. In addition, the structure of seeds and Na+ distribution in the seed coat and embryos of dry seeds were investigated. • Key Results The relative increase in fresh weight of germinating seeds was markedly reduced in ?2·24?MPa PEG compared with that in ?2·24?MPa NaCl, while the opposite trend was found in concentration of K+ during the initial 9?h for all species. Haloxylon ammodendron and S. physophora had a higher recovery germination from ?3·13?MPa NaCl compared with H. persicum. Seeds of all species had no endosperm. More Na+ was compartmentalized in the seed coats of the two halophytic species compared with that in the xerophyte H. persicum. • Conclusions The effect of NaCl on seed germination was due to both osmotic stress and ion toxicity for the three species. High soil salinity and a high content of Na+ in seeds may induce more seeds to remain ungerminated in S. physophora and H. ammodendron. Morphological structure and adaptation to salinity during seed germination may determine the geographical distribution of H. ammodendron and S. physophora in certain saline regions. PMID:16002418

SONG, JIE; FENG, GU; TIAN, CHANGYAN; ZHANG, FUSUO

2005-01-01

387

Variation in germination and amino Acid leakage of seeds with temperature related to membrane phase change.  

PubMed

Leakages of amino acids and/or fluorescent material as functions of temperature between 15 and 40 C are reported for imbibed seeds of Avena fatua L., Lactuca sativa L., Barbarea vulgaris R. Br., Amaranthus albus L., Abutilon theophrasti Medic., Lychnis alba Mill., Daucus carota L., Setaria faberi Herrm., Setaria viridis (L.) Beauv., and Datura stramonium L. The leakage indicates prominent increase in permeability of the plasmalemma in the 30 to 35 C range for 8 of the 10 kinds of seeds studied. Germination of the seeds at constant temperatures or with daily shifts in temperature is related to the membrane transition temperature for permeation by amino acids. Seeds of A. albus and A. theophrasti, which did not show membrane changes in the 25 to 40 C range, germinated best at 35 to 40 C; the other seeds germinated best below 30 C. Seeds of B. vulgaris showed rapid permeation of limiting membranes upon initial wetting with water, which was indicative of membrane disorder when dry. Leakage under anaerobiosis was observed for S. faberi seeds. PMID:16659623

Hendricks, S B; Taylorson, R B

1976-07-01

388

Variation in Germination and Amino Acid Leakage of Seeds with Temperature Related to Membrane Phase Change  

PubMed Central

Leakages of amino acids and/or fluorescent material as functions of temperature between 15 and 40 C are reported for imbibed seeds of Avena fatua L., Lactuca sativa L., Barbarea vulgaris R. Br., Amaranthus albus L., Abutilon theophrasti Medic., Lychnis alba Mill., Daucus carota L., Setaria faberi Herrm., Setaria viridis (L.) Beauv., and Datura stramonium L. The leakage indicates prominent increase in permeability of the plasmalemma in the 30 to 35 C range for 8 of the 10 kinds of seeds studied. Germination of the seeds at constant temperatures or with daily shifts in temperature is related to the membrane transition temperature for permeation by amino acids. Seeds of A. albus and A. theophrasti, which did not show membrane changes in the 25 to 40 C range, germinated best at 35 to 40 C; the other seeds germinated best below 30 C. Seeds of B. vulgaris showed rapid permeation of limiting membranes upon initial wetting with water, which was indicative of membrane disorder when dry. Leakage under anaerobiosis was observed for S. faberi seeds. PMID:16659623

Hendricks, Sterling B.; Taylorson, Ray B.

1976-01-01

389

A systematic proteomic analysis of NaCl-stressed germinating maize seeds.  

PubMed

Salt (NaCl) is a common physiological stressor of plants. To better understand how germinating seeds respond to salt stress, we examined the changes that occurred in the proteome of maize seeds during NaCl-treated germination. Phenotypically, salt concentrations less than 0.2 M appear to delay germination, while higher concentrations disrupt development completely, leading to seed death. The identities of 96 proteins with expression levels altered by NaCl-incubation were established using 2-DE-MALDI-TOF-MS and 2-DE-MALDI-TOF-MS/MS. Of these 96 proteins, 79 were altered greater than twofold when incubated with a 0.2 M salt solution, while 51 were altered when incubated with a 0.1 M salt solution. According to their functional annotations in the Swiss-Prot protein-sequence databases, these proteins are mainly involved in seed storage, energy metabolism, stress response, and protein metabolism. Notably, the expression of proteins that respond to abscisic acid signals increased in response to salt stress. The results of this study provide important clues as to how NaCl stresses the physiology of germinating maize seeds. PMID:24700167

Meng, Ling-Bo; Chen, Yi-Bo; Lu, Tian-Cong; Wang, Yue-Feng; Qian, Chun-Rong; Yu, Yang; Ge, Xuan-Liang; Li, Xiao-Hui; Wang, Bai-Chen

2014-05-01

390

Polyamines, IAA and ABA during germination in two recalcitrant seeds: Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm)  

PubMed Central

Background and Aims Plant growth regulators play an important role in seed germination. However, much of the current knowledge about their function during seed germination was obtained using orthodox seeds as model systems, and there is a paucity of information about the role of plant growth regulators during germination of recalcitrant seeds. In the present work, two endangered woody species with recalcitrant seeds, Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm), native to the Atlantic Rain Forest, Brazil, were used to study the mobilization of polyamines (PAs), indole-acetic acid (IAA) and abscisic acid (ABA) during seed germination. Methods Data were sampled from embryos of O. odorifera and embryos and megagametophytes of A. angustifolia throughout the germination process. Biochemical analyses were carried out in HPLC. Key Results During seed germination, an increase in the (Spd + Spm) : Put ratio was recorded in embryos in both species. An increase in IAA and PA levels was also observed during seed germination in both embryos, while ABA levels showed a decrease in O. odorifera and an increase in A. angustifolia embryos throughout the period studied. Conclusions The (Spd + Spm) : Put ratio could be used as a marker for germination completion. The increase in IAA levels, prior to germination, could be associated with variations in PA content. The ABA mobilization observed in the embryos could represent a greater resistance to this hormone in recalcitrant seeds, in comparison to orthodox seeds, opening a new perspective for studies on the effects of this regulator in recalcitrant seeds. The gymnosperm seed, though without a connective tissue between megagametophyte and embryo, seems to be able to maintain communication between the tissues, based on the likely transport of plant growth regulators. PMID:21685432

Pieruzzi, Fernanda P.; Dias, Leonardo L. C.; Balbuena, Tiago S.; Santa-Catarina, Claudete; dos Santos, André L. W.; Floh, Eny I. S.

2011-01-01

391

Dynamic Proteomics Emphasizes the Importance of Selective mRNA Translation and Protein Turnover during Arabidopsis Seed Germination*  

PubMed Central

During seed germination, the transition from a quiescent metabolic state in a dry mature seed to a proliferative metabolic state in a vigorous seedling is crucial for plant propagation as well as for optimizing crop yield. This work provides a detailed description of the dynamics of protein synthesis during the time course of germination, demonstrating that mRNA translation is both sequential and selective during this process. The complete inhibition of the germination process in the presence of the translation inhibitor cycloheximide established that mRNA translation is critical for Arabidopsis seed germination. However, the dynamics of protein turnover and the selectivity of protein synthesis (mRNA translation) during Arabidopsis seed germination have not been addressed yet. Based on our detailed knowledge of the Arabidopsis seed proteome, we have deepened our understanding of seed mRNA translation during germination by combining two-dimensional gel-based proteomics with dynamic radiolabeled proteomics using a radiolabeled amino acid precursor, namely [35S]-methionine, in order to highlight de novo protein synthesis, stability, and turnover. Our data confirm that during early imbibition, the Arabidopsis translatome keeps reflecting an embryonic maturation program until a certain developmental checkpoint. Furthermore, by dividing the seed germination time lapse into discrete time windows, we highlight precise and specific patterns of protein synthesis. These data refine and deepen our knowledge of the three classical phases of seed germination based on seed water uptake during imbibition and reveal that selective mRNA translation is a key feature of seed germination. Beyond the quantitative control of translational activity, both the selectivity of mRNA translation and protein turnover appear as specific regulatory systems, critical for timing the molecular events leading to successful germination and seedling establishment. PMID:24198433

Galland, Marc; Huguet, Romain; Arc, Erwann; Cueff, Gwendal; Job, Dominique; Rajjou, Loïc

2014-01-01

392

Seed dormancy-breaking and germination requirements of Drosera anglica, an insectivorous species of the Northern Hemisphere  

NASA Astrophysics Data System (ADS)

Seeds of Drosera anglica collected in Sweden were dormant at maturity in late summer, and dormancy break occurred during cold stratification. Stratified seeds required light for germination, but light had to be given after temperatures were high enough to be favorable for germination. Seeds stratified in darkness at 5/1 °C and incubated in light at 12/12 h daily temperature regimes of 15/6, 20/10 and 25/15 °C germinated slower and to a significantly lower percentage at each temperature regime than those stratified in light and incubated in light. Length of the stratification period required before seeds would germinate to high percentages depended on (1) whether seeds were in light or in darkness during stratification and during the subsequent incubation period, and (2) the temperature regime during incubation. Seeds collected in 1999 germinated to 4, 24 and 92 % in light at 15/6, 20/10 and 25/15 °C, respectively, after 2 weeks of stratification in light. Seeds stratified in light for 18 weeks and incubated in light at 15/6, 20/10 and 25/15 °C germinated to 87, 95 and 100 %, respectively, while those stratified in darkness for 18 weeks and incubated in light germinated to 6, 82 and 91 %, respectively. Seeds collected from the same site in 1998 and 1999, stratified in light at 5/1 °C and incubated in light at 15/6 °C germinated to 22 and 87 %, respectively, indicating year-to-year variation in degree of dormancy. As dormancy break occurred, the minimum temperature for germination decreased. Thus, seed dormancy is broken in nature by cold stratification during winter, and by spring, seeds are capable of germinating at low habitat temperatures, if they are exposed to light.

Baskin, Carol C.; Milberg, Per; Andersson, Lars; Baskin, Jerry M.

2001-02-01

393

Cold Radiofrequency Plasma Treatment Modifies Wettability and Germination Speed of Plant Seeds  

PubMed Central

We report the possibility to modify the wetting properties of the surfaces of a diversity of seeds including: lentils (Lens culinaris), beans (Phaseolus vulgaris) and wheat (Triticum, species C9) by cold radiofrequency air plasma treatment. Air plasma treatment leads to the dramatic decrease in the apparent contact angle. Moreover, the speed of germination and yield (germination rate) of seeds can be modified by preliminary plasma treatment. The change in the wetting properties of seeds is at least partially due to oxidation of their surface under plasma treatment. Significant growth of the peaks corresponding to the nitrogen containing groups in the mass spectra of air plasma treated seeds was registered by TOF-SIMS spectroscopy. PMID:23077725

Bormashenko, Edward; Grynyov, Roman; Bormashenko, Yelena; Drori, Elyashiv

2012-01-01

394

Digital Imaging Information Technology Applied to Seed Germination Testing: A Review  

Microsoft Academic Search

The application of digital imaging information technology to seed germination testing is discussed. This technology is reviewed\\u000a in light of recent interest on the development and adoption of sustainable agrosystems joined with a modern strategy of “precision\\u000a agriculture”, which provides new complex information tools for better crop production. Basic concepts on the patterns of image\\u000a analysis descriptors of imbibing seed

Antonio Dell’ Aquila

395

Digital imaging information technology applied to seed germination testing. A review  

Microsoft Academic Search

The application of digital imaging information technology to seed germination testing is discussed. This technology is reviewed\\u000a in light of recent interest on the development and adoption of sustainable agrosystems joined with a modern strategy of “precision\\u000a agriculture”, which provides new complex information tools for better crop production. Basic concepts on the patterns of image\\u000a analysis descriptors of imbibing seed

Antonio Dell’ Aquila

2009-01-01

396

Spatially regulated genes expressed during seed germination and postgerminative development are activated during embryogeny  

Microsoft Academic Search

We investigated the control of genes expressed primarily during seed germination and postgerminative development in Brassica napus L. We identified cloned mRNA sequences which became prevalent within 1 day after the start of imbibition and were at low or undetectable levels in immature embryos, dry seeds, and leaves. Most postgermination-abundant mRNAs accumulated primarily, though not exclusively, in different parts of

John J. Harada; Catherine S. Baden; Lucio Comai

1988-01-01

397

Seed germination conditions and implications for establishment of an epiphyte, Aechmea bracteata (Bromeliaceae)  

Microsoft Academic Search

Aechmea bracteata is a common epiphytic bromeliad found in symbiosis with many other species throughout tropical forests of Mexico and south\\u000a through Panama. Given its importance and distribution in these forests, we asked how may A. bracteata be restored to areas where they have thrived in the past? We first investigated seed viability and response of seed germination\\u000a to temperature,

Laurel K. Goode; Michael F. Allen

2009-01-01

398

The Effects of Moist-Heat Treatments and Stratification on Germination of Prairie Plant Seeds  

Microsoft Academic Search

Germination of Silphium terebinthenaceum was enhanced by a post-stratification most-heat treatment at 80°C. Tested seeds of four other perennial herbs common to midwestern prairies (Andropogon scoparius, Sorghastrum nutans, Eryngium yuccifolium, and Solidago rigida) showed little adverse or beneficial effects of the heat treatment. Heat treatments alone had little effect on the seeds; the length of stratification periods necessary to effect

John E. Stuurwold

1972-01-01

399

Arabidopsis thaliana DOF6 negatively affects germination in non-after-ripened seeds and interacts with TCP14.  

PubMed

Seed dormancy prevents seeds from germinating under environmental conditions unfavourable for plant growth and development and constitutes an evolutionary advantage. Dry storage, also known as after-ripening, gradually decreases seed dormancy by mechanisms not well understood. An Arabidopsis thaliana DOF transcription factor gene (DOF6) affecting seed germination has been characterized. The transcript levels of this gene accumulate in dry seeds and decay gradually during after-ripening and also upon seed imbibition. While constitutive over-expression of DOF6 produced aberrant growth and sterility in the plant, its over-expression induced upon seed imbibition triggered delayed germination, abscisic acid (ABA)-hypersensitive phenotypes and increased expression of the ABA biosynthetic gene ABA1 and ABA-related stress genes. Wild-type germination and gene expression were gradually restored during seed after-ripening, despite of DOF6-induced over-expression. DOF6 was found to interact in a yeast two-hybrid system and in planta with TCP14, a previously described positive regulator of seed germination. The expression of ABA1 and ABA-related stress genes was also enhanced in tcp14 knock-out mutants. Taken together, these results indicate that DOF6 negatively affects seed germination and opposes TCP14 function in the regulation of a specific set of ABA-related genes. PMID:22155632

Rueda-Romero, Paloma; Barrero-Sicilia, Cristina; Gómez-Cadenas, Aurelio; Carbonero, Pilar; Oñate-Sánchez, Luis

2012-03-01

400

Ethylene Production is Associated with Germination but not Seed Dormancy in Red Rice  

PubMed Central

Background and Aims The relationship between ethylene production and both seed dormancy and germination was investigated using red rice (weedy rice) as a model species. Methods Both fully dormant and after-ripened (non-dormant) naked caryopses were incubated with or without inhibitors of ethylene synthesis [aminoethoxyvinylglycine (AVG)] and perception [silver thiosulfate (STS)], or in the presence of the natural ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). The kinetics of ethylene emissions were measured with a sensitive laser–photoacoustic system. Key Results Dormant red rice caryopses did not produce ethylene. In non-dormant caryopses, ethylene evolution never preceded the first visible stage of germination (pericarp splitting), and ethylene inhibitors completely blocked ethylene production, but not pericarp splitting. Accordingly, endogenous ACC appeared to be lacking before pericarp splitting. However, early seedling growth (radicle or coleoptile attaining the length of 1 mm) followed ethylene evolution and was delayed by the inhibitors. Wounding the dormant caryopses induced them to germinate and produce ethylene, but their germination was slow and pericarp splitting could be speeded up by ethylene. Conclusions The findings suggest that, in red rice, endogenous ethylene stimulates the growth of the nascent seedling, but does not affect seed dormancy or germination inception. Correspondingly, this phytohormone does not play a role in the dormancy breakage induced by wounding, but accelerates germination after such breakage has occurred. PMID:17347162

Gianinetti, Alberto; Laarhoven, Lucas J. J.; Persijn, Stefan T.; Harren, Frans J. M.; Petruzzelli, Luciana

2007-01-01

401

Seed Germination Ecology of Feather Lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes  

PubMed Central

Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha-1 was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies. PMID:24255700

Chauhan, Bhagirath S.

2013-01-01

402

Seed germination ecology of feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes].  

PubMed

Feather lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes] is a C4 grass weed that has the ability to grow in both lowland and upland conditions. Experiments were conducted in the laboratory and screenhouse to evaluate the effect of environmental factors on germination, emergence, and growth of this weed species. Germination in the light/dark regime was higher at alternating day/night temperatures of 30/20 °C (98%) than at 35/25 °C (83%) or 25/15 °C (62%). Germination was completely inhibited by darkness. The osmotic potential and sodium chloride concentrations required for 50% inhibition of maximum germination were -0.7 MPa and 76 mM, respectively. The highest seedling emergence (69%) was observed from the seeds sown on the soil surface and no seedlings emerged from seeds buried at depths of 0.5 cm or more. The use of residue as mulches significantly reduced the emergence and biomass of feather lovegrass seedlings. A residue amount of 0.5 t ha(-1) was needed to suppress 50% of the maximum seedlings. Because germination was strongly stimulated by light and seedling emergence was the highest for the seeds sown on the soil surface, feather lovegrass is likely to become a problematic weed in zero-till systems. The knowledge gained from this study could help in developing effective and sustainable weed management strategies. PMID:24255700

Chauhan, Bhagirath S

2013-01-01

403

Effect of new organic supplement (Panchgavya) on seed germination and soil quality.  

PubMed

We studied the suitability of Panchgavya (five products of cow), new organic amendment, application on seed germination, plant growth, and soil health. After characterization, Panchgavya was mixed with water to form different concentration and was tested for seed germination, germination index, and root and shoot growth of different seedlings. Four percent solution of Panchgavya was applied to different plants to test its efficacy. Panchgavya and other two organic amendments were incorporated in soil to test the change of soil chemical and microbiological parameters. Panchgavya contained higher nutrients as compared to farm yard manure (FYM) and vermicompost. Its application on different seeds has positively influenced germination percentage, germination index, root and shoot length, and fresh and dry weight of the seedling. Water-soluble macronutrients including pH and metal were positively and negatively correlated with the growth parameters, respectively. Four percent solution of Panchgavya application on some plants showed superiority in terms of plant height and chlorophyll content. Panchgavya-applied soil had higher values of macro and micronutrients (zinc, copper, and manganese), microbial activity as compared to FYM, and vermicompost applied soils. Application of Panchgavya can be gainfully used as an alternative organic supplement in agriculture. PMID:24234225

Jain, Paras; Sharma, Ravi Chandra; Bhattacharyya, Pradip; Banik, Pabitra

2014-04-01

404

Lifting DELLA Repression of Arabidopsis Seed Germination by Nonproteolytic Gibberellin Signaling1[C][W][OPEN  

PubMed Central

DELLA repression of Arabidopsis (Arabidopsis thaliana) seed germination can be lifted either through DELLA proteolysis by the ubiquitin-proteasome pathway or through proteolysis-independent gibberellin (GA) hormone signaling. GA binding to the GIBBERELLIN-INSENSITIVE DWARF1 (GID1) GA receptors stimulates GID1-GA-DELLA complex formation, which in turn triggers DELLA protein ubiquitination and proteolysis via the SCFSLY1 E3 ubiquitin ligase and 26S proteasome. Although DELLA cannot be destroyed in the sleepy1-2 (sly1-2) F-box mutant, long dry after-ripening and GID1 overexpression can relieve the strong sly1-2 seed dormancy phenotype. It appears that sly1-2 seed dormancy results from abscisic acid (ABA) signaling downstream of DELLA, since dormant sly1-2 seeds accumulate high levels of ABA hormone and loss of ABA sensitivity rescues sly1-2 seed germination. DELLA positively regulates the expression of XERICO, an inducer of ABA biosynthesis. GID1b overexpression rescues sly1-2 germination through proteolysis-independent DELLA down-regulation associated with increased expression of GA-inducible genes and decreased ABA accumulation, apparently as a result of decreased XERICO messenger RNA levels. Higher levels of GID1 overexpression are associated with more efficient sly1 germination and increased GID1-GA-DELLA complex formation, suggesting that GID1 down-regulates DELLA through protein binding. After-ripening results in increased GA accumulation and GID1a-dependent GA signaling, suggesting that after-ripening triggers GA-stimulated GID1-GA-DELLA protein complex formation, which in turn blocks DELLA transcriptional activation of the XERICO inhibitor of seed germination. PMID:23818171

Ariizumi, Tohru; Hauvermale, Amber L.; Nelson, Sven K.; Hanada, Atsushi; Yamaguchi, Shinjiro; Steber, Camille M.

2013-01-01

405

Lifting della repression of Arabidopsis seed germination by nonproteolytic gibberellin signaling.  

PubMed

DELLA repression of Arabidopsis (Arabidopsis thaliana) seed germination can be lifted either through DELLA proteolysis by the ubiquitin-proteasome pathway or through proteolysis-independent gibberellin (GA) hormone signaling. GA binding to the GIBBERELLIN-INSENSITIVE DWARF1 (GID1) GA receptors stimulates GID1-GA-DELLA complex formation, which in turn triggers DELLA protein ubiquitination and proteolysis via the SCF(SLY1) E3 ubiquitin ligase and 26S proteasome. Although DELLA cannot be destroyed in the sleepy1-2 (sly1-2) F-box mutant, long dry after-ripening and GID1 overexpression can relieve the strong sly1-2 seed dormancy phenotype. It appears that sly1-2 seed dormancy results from abscisic acid (ABA) signaling downstream of DELLA, since dormant sly1-2 seeds accumulate high levels of ABA hormone and loss of ABA sensitivity rescues sly1-2 seed germination. DELLA positively regulates the expression of XERICO, an inducer of ABA biosynthesis. GID1b overexpression rescues sly1-2 germination through proteolysis-independent DELLA down-regulation associated with increased expression of GA-inducible genes and decreased ABA accumulation, apparently as a result of decreased XERICO messenger RNA levels. Higher levels of GID1 overexpression are associated with more efficient sly1 germination and increased GID1-GA-DELLA complex formation, suggesting that GID1 down-regulates DELLA through protein binding. After-ripening results in increased GA accumulation and GID1a-dependent GA signaling, suggesting that after-ripening triggers GA-stimulated GID1-GA-DELLA protein complex formation, which in turn blocks DELLA transcriptional activation of the XERICO inhibitor of seed germination. PMID:23818171

Ariizumi, Tohru; Hauvermale, Amber L; Nelson, Sven K; Hanada, Atsushi; Yamaguchi, Shinjiro; Steber, Camille M

2013-08-01

406

Comparison of germination and seed vigor of sunflower in two contaminated soils of different texture  

NASA Astrophysics Data System (ADS)

Phytoremediation as an emerging low-cost and ecologically friendly alternative to the conventional soil remediation technologies has gained a great deal of attention and into lots of research. As a kind of the methods that use of green plants to remediate heavy metals contaminated soils, the early growth status of plant seeds in the contaminated environmental directly affects the effect of phytoremediation. Germination test in the water (aqueous solution of heavy metal) is generally used for assessing heavy metal phytotoxicity and possibility of plant growth, but there is a limit. Because soil is commonly main target of phytoremediation, not the water. The bioavailability of heavy metals in the soil also depends on the texture. So soil texture is an important factor of phytoremediation effect. Sunflower is the representative species which have good tolerance to various heavy metals; furthermore, the seeds of sunflower can be used as the raw-material for producing bio-diesel. The objectives of this research were to investigate germination rate of sunflowers in various heavy metal contaminated soils and to compare the seedling vigor index (SVI) of sunflower in two contaminated soils of different texture. Sunflower (Helianthusannuus L.) seeds were obtained from a commercial market. In order to prove the soil texture effect on heavy metal contaminated soil, germination tests in soil were conducted with two different types of soil texture (i.e., loam soil and sandy loam soil) classified by soil textural triangle (defined by USDA) including representative soil texture of Korea. Germination tests in soil were conducted using KS I ISO 11260-1 (2005) for reference that sunflower seeds were incubated for 7 days in dark at 25 ± 1 Celsius degree. The target heavy metals are Nickel (Ni) and Zinc (Zn). The Ni and Zn concentrations were 0, 10, 50, 100, 200, 300, 500 mg-Ni/kg-dry soil, and 0, 10, 50, 100, 300, 500, 900 mg-Zn/kg-dry soil, respectively. After germination test for 7 days, germination rate of sunflower was calculated, and shoot and root lengths were also measured. According to the results of germination tests, the seeds germination rates were reduced with increasing heavy metal concentrations in both loam soil and sandy loam soil. The SVI values in loam soil in more than in sandy loam soil. Keywords: phytoremediation, sunflower, soil texture, germination test ACKNOWLEDGEMENT This work is supported by the Korea Ministry of the Environment as 'The GAIA (Geo-Advanced Innovative Action) Project'.

Zhao, Xin; Han, Jaemaro; Lee, Jong Keun; Kim, Jae Young

2014-05-01

407

Cryopreservation of lipid-rich seeds: effect of moisture content and cooling rate on germination.  

PubMed

The effect of fast and slow cooling on germination of seeds from two Brassicaceae species (Eruca vesicaria (L.) Cav., Brassica napus L. var. oleifera (Moench) DC cv. Bingo) and cypselas from three Compositae species (Onopordum nervosum Boiss., Onopordum acanthium L., Helianthus annuus L. cv. Viky) at different moisture contents was studied. Seed lipid content (dry weight basis) ranged from 15% (O. nervosum) to 41% (H. annuus). For each species, seeds with four moisture contents were cryopreserved either by direct immersion in liquid nitrogen or by previous cooling at 10 degrees C/min from room temperature to -50 degrees C. In three species (E. vesicaria, B. napus, and H. annuus) germination of air-dried (6.2-8.9% moisture content) seeds cooled by direct immersion in liquid nitrogen was not significantly different from germination of control seeds (air-dried, non-cooled). In the two Onorpordum species the best response among cooling treatments was observed when air-dried seeds were slowly cooled. PMID:11788852

González-Benito, E M; Pérez-García, F

2001-01-01

408

Interaction of light and temperature on seed germination of Rumex obtusifolius L.  

PubMed

Germination of Rumex obtusifolius L. seeds (nutlets) is low in darkness at 25° C. Germination is stimulated by exposure to 10 min red light (R) and also by a 10-min elevation of temperature to 35° C. A 10-min exposure to far-red light (FR) can reverse the effect of both R (indicating phytochrome control) and 35° C treatment. Fluence-response curves for this reversal of the effect of R and 35° C treatments are quantitatively identical. Treatment for 10 min with light of wavelenght 680, 700, 710 and 730 nm, after R and 35° C treatment, demonstrates that germination induced by 35° C treatment results from increased sensitivity to a pre-existing, active, far-red-absorbing form of phytochrome (Pfr) in the seeds. PMID:24272659

Hand, D J; Craig, G; Takaki, M; Kendrick, R E

1982-12-01

409

Germination, growth rates, and electron microscope analysis of tomato seeds flown on the LDEF  

SciTech Connect

The tomato seeds were flown in orbit aboard the Long Duration Exposure Facility (LDEF) for nearly six years. During this time, the tomato seeds received an abundant exposure to cosmic radiation and solar wind. Upon the return of the LDEF to earth, the seeds were distributed throughout the United States and 30 foreign countries for analysis. The purpose of the experiment was to determine the long term effect of cosmic rays on living tissue. Our university analysis included germination and growth rates as well as Scanning Electron Microscopy and X-ray analysis of the control as well as Space-exposed tomato seeds. In analyzing the seeds under the Electron Microscope, usual observations were performed on the nutritional and epidermis layer of the seed. These layers appeared to be more porous in the Space-exposed seeds than on the Earth-based control seeds. This unusual characteristic may explain the increases in the space seeds growth pattern. (Several test results show that the Space-exposed seeds germinate sooner than the Earth-Based seeds. Also, the Space-exposed seeds grew at a faster rate). The porous nutritional region may allow the seeds to receive necessary nutrients and liquids more readily, thus enabling the plant to grow at a faster rate. Roots, leaves and stems were cut into small sections and mounted. After sputter coating the specimens with Argon/Gold Palladium Plasma, they were ready to be viewed under the Electron Microscope. Many micrographs were taken. The X-ray analysis displayed possible identifications of calcium, potassium, chlorine, copper, aluminum, silicon, phosphate, carbon, and sometimes sulfur and iron. The highest concentrations were shown in potassium and calcium. The Space-exposed specimens displayed a high concentration of copper and calcium in the two specimens. There was a significantly high concentration of copper in the Earth-based specimens, whereas there was no copper in the Space-exposed specimens.

Hammond, E.C. Jr.; Bridgers, K.; Brown, C.W.

1995-02-01

410

Do seed mass and family affect germination and juvenile performance in Knautia arvensis? A study using failure-time methods  

Microsoft Academic Search

Germination and seedling establishment are vulnerable stages in the plant life cycle. We investigated how seed mass and family (progeny origin) affect germination and juvenile performance in the grassland herb Knautia arvensis. Seeds were produced by cross-pollination by hand. The fate of 15 individually weighed seeds from each of 15 plants was followed during a 3-month growth chamber experiment. Progeny origin affected

Vibekke Vange; Ivar Heuch; Vigdis Vandvik

2004-01-01

411

The roles of inorganic nitrogen salts in maintaining phytochrome- and gibberellin A 3 -mediated germination control in skotodormant lettuce seeds  

Microsoft Academic Search

Skotodormant seeds of Lactuca sativa Grand Rapids imbibed in darkness for 10 days (10-day DS) germinated poorly upon terminal treatment with red light (R) or\\u000a gibberellin A3 (GA3). Inorganic nitrogen salts in the imbibition solutions reduced seed skotodormancy. Ten-day DS seeds, imbibed in 25 mm salt solutions followed by terminal R, germinated 99% if imbibed in NH4NO3, 70% if imbibed

A. I. Hsiao; W. A. Quick

1996-01-01

412

Promotion of seed germination, subsequent seedling growth and in vitro propagation of korarima Aframomum corrorima (Braun) P. C. M. Jansen)  

Microsoft Academic Search

The germination of korarima (Aframomum corrorima (Braun) P.C.M. Jansen) seeds faces certain problems. The study was carried out to explore the effects of different seed treatments on germination and seedling growth attributes of korarima. Seeds were subjected to seven pre-sowing treatments viz., control (no pretreatment) (T0), soaking in tap water for 24 h (T1), soaking in 50% sulfuric acid (H2SO4)

S. Eyob

413

Influence of Biocontrol Insects on Canada Thistle: Seed Production, Germinability, and Viability  

Microsoft Academic Search

We conducted surveys of thistle-feeding insects on Canada thistle (Cirsium arvense (L.) Scop.) during the 2000 and 2001 growing seasons at Lacreek National Wildlife Refuge (LNWR), South Dakota, and analyzed their impact on thistle seed production, germination, and viability. Insects included Canada thistle stem weevil (Hadroplontus litura, formerly Ceurtorhynchus litura, (Coleoptera: Curculionidae)), introduced at LNWR as a biocontrol agent, plus

GARY E. LARSON; TIM A. WITTIG; KENNETH F. HIGGINS; BRENT TURNIPSEED; DAWN M. GARDNER

414

Ethylene Inhibition of Phytochrome-Induced Germination in Potentilla norvegica L. Seeds  

PubMed Central

Germination of Potentilla norvegica L. (rough cinquefoil) seeds stimulated by fluorescent irradiations of nearly 24 hours was inhibited by ethylene at <1 microliter per liter. Sensitivity to ethylene inhibition was highest during and immediately after the irradiation. By delaying ethylene treatment until about a day after the light potentiation, seeds escaped the inhibition. Ethylene inhibition may be readily reversed upon release of the gas and reirradiation of the seeds. Imbibition of seeds at 10 or 15°C, or at high temperatures of 35 and 40°C, partially prevented subsequent inhibition by ethylene. Alternating temperatures during germination nearly overcame the inhibition from 1 microliter per liter ethylene, but not higher doses. With brief red-irradiation and alternating temperatures, 0.1 microliter per liter ethylene promoted germination about 2-fold. These data suggest that ethylene may loosely associate on a site required for phytochrome action. The effect of temperature that opposed the inhibition may be to deny the association of ethylene with the site. Loose association is supported by the reversal of inhibition by gas release and increased temperature during germination. A blocking effect was shown by the failure of phytochrome to act when ethylene was present. PMID:16662113

Suzuki, Shoho; Taylorson, Ray B.

1981-01-01

415

Ethylene Inhibition of Phytochrome-Induced Germination in Potentilla norvegica L. Seeds.  

PubMed

Germination of Potentilla norvegica L. (rough cinquefoil) seeds stimulated by fluorescent irradiations of nearly 24 hours was inhibited by ethylene at <1 microliter per liter. Sensitivity to ethylene inhibition was highest during and immediately after the irradiation. By delaying ethylene treatment until about a day after the light potentiation, seeds escaped the inhibition. Ethylene inhibition may be readily reversed upon release of the gas and reirradiation of the seeds. Imbibition of seeds at 10 or 15 degrees C, or at high temperatures of 35 and 40 degrees C, partially prevented subsequent inhibition by ethylene. Alternating temperatures during germination nearly overcame the inhibition from 1 microliter per liter ethylene, but not higher doses. With brief red-irradiation and alternating temperatures, 0.1 microliter per liter ethylene promoted germination about 2-fold. These data suggest that ethylene may loosely associate on a site required for phytochrome action. The effect of temperature that opposed the inhibition may be to deny the association of ethylene with the site. Loose association is supported by the reversal of inhibition by gas release and increased temperature during germination. A blocking effect was shown by the failure of phytochrome to act when ethylene was present. PMID:16662113

Suzuki, S; Taylorson, R B

1981-12-01

416

Field emergence and plant density of sand bluestem lines selected for increased seed germination.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Sand bluestem (Andropogon hallii Hack.) populations AB-medium Syn-1 and Syn-2, and CD-tall Syn-1 and Syn-2 were developed from populations AB-medium Syn-0 and CD-tall Syn-0 by recurrent selection for increased seed germination in low water potentials. The objective of this research was to verify if...

417

The effects of maternal salinity and seed environment on germination and growth in Iris hexagona  

E-print Network

The effects of maternal salinity and seed environment on germination and growth in Iris hexagona hexagona occupy saline habitats and plant performance is strongly impacted by salinity stress. We examined. hexagona by (1) growing plants in three different maternal salinity levels in a common garden, (2

Van Zandt, Peter

418

Stored proteinases and the initiation of storage protein mobilization in seeds during germination and seedling growth  

Microsoft Academic Search

Though endopeptidases and carboxypeptidases are present in protein bodies of dry quiescent seeds the function of these proteases during germination is still a matter of debate. In some plants it was demonstrated that endopeptidases of dry protein bodies degrade storage proteins of these organelles. Other studies describe cases where this did not happen. The role that stored proteinases play in

K. Muntz; M. A. Belozersky; Y. E. Dunaevsky; A. Schlereth; J. Tiedemann

2001-01-01

419

Mycorrhizal fungi of Vanilla: diversity, specificity and effects on seed germination and plant growth  

Microsoft Academic Search

Mycorrhizal fungi are essential for the germination of orchid seeds. However, the specificity of orchids for their mycorrhizal fungi and the effects of the fungi on orchid growth are controversial. Mycorrhizal fungi have been studied in some tem- perate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function

Andrea Porras-Alfaro; Paul Bayman

2007-01-01

420

Seed germination-influencing bioactive secondary metabolites secreted by the endophyte Cladosporium cladosporioides LWL5.  

PubMed

The present study was aimed to isolate bioactive metabolites produced by a fungal endophyte from Helianthus annuus, Capsicum annuum, and Cucumis sativus and to assess their role in seed germination. Culture filtrate of the endophyte HA-3B from H. annuus was significantly inhibitory towards the germination and growth of lettuce seeds. HA-3B was identified as Cladosporium cladosporioides LWL5 through molecular techniques. Different concentrations (100, 500 and 1000 ppm) of the ethyl acetate extract obtained from the culture inhibited the lettuce seed germination. The extract was subjected to column chromatography and a bioassay-guided isolation method, which yielded compounds 1, 2 and an oily fraction. The oily fraction, subjected to fractionation and spectroscopic techniques, resulted in the identification of 31 different constituents. Compounds 1 and 2 were identified and characterized through MS and NMR spectroscopic techniques as benzoic acid. The bioassay results showed that this compound significantly inhibited the growth and germination of lettuce seeds. In conclusion, assessing the role of endophytes harboring essential crop plants can help us to develop potentially eco-friendly herbicides. PMID:24352011

Waqas, Muhammad; Khan, Abdul Latif; Ali, Liaqat; Kang, Sang-Mo; Kim, Yoon-Ha; Lee, In-Jung

2013-01-01

421

In Vivo Effects of Barbituates on Seed Germination and Seedling Growth.  

ERIC Educational Resources Information Center

A simple, low-cost experimental system can be used to demonstrate the "in vivo" effects of barbituates on seed germination and seedling growth behavior in different plant species. Lipid solubility and concentration of individual barbituates both affect the response. List of materials needed, procedures used, and typical results obtained are…

Kordan, H. A.

1984-01-01

422

DOES SEED SIZE AFFECT THE RATE OF GERMINATION AND EARLY SEEDLING GROWTH IN HAIRY VETCH?  

Technology Transfer Automated Retrieval System (TEKTRAN)

In many crops there is a positive correlation between seed size and the rate of germination and seedling establishment. Hairy vetch (Vicia villosa, Roth) is an annual cool-season legume used primarily for soil improvement or for forage. In the Southern Great Plains its growing season is limited to...

423

Effect of Cold Plasma Treatment on Seed Germination and Growth of Wheat  

NASA Astrophysics Data System (ADS)

This study investigated the effect of cold helium plasma treatment on seed germination, growth and yield of wheat. The effects of different power of cold plasma on the germination of treated wheat seeds were studied. We found that the treatment of 80 W could significantly improve seed germination potential (6.0%) and germination rate (6.7%) compared to the control group. Field experiments were carried out for wheat seeds treated with 80 W cold plasma. Compared with the control, plant height (20.3%), root length (9.0%) and fresh weight (21.8%) were improved significantly at seedling stage. At booting stage, plant height, root length, fresh weight, stem diameter, leaf area and leaf thickness of the treated plant were respectively increased by 21.8%, 11.0%, 7.0%, 9.0%, 13.0% and 25.5%. At the same time, the chlorophyll content (9.8%), nitrogen (10.0%) and moisture content (10.0%) were higher than those of the control, indicating that cold plasma treatment could promote the growth of wheat. The yield of treated wheat was 7.55 t · ha-1, 5.89% more than that of the control. Therefore, our results show that cold plasma has important application prospects for increasing wheat yield.

Jiang, Jiafeng; He, Xin; Li, Ling; Li, Jiangang; Shao, Hanliang; Xu, Qilai; Ye, Renhong; Dong, Yuanhua

2014-01-01

424

Lifting DELLA repression of Arabidopsis seed germination by nonproteolytic gibberellin signaling  

Technology Transfer Automated Retrieval System (TEKTRAN)

DELLA repression of Arabidopsis seed germination can be lifted through the ubiquitin-proteasome pathway and proteolysis-independent GA signaling. GA-binding to the GID1 (GIBBERELLIN-INSENSITIVE DWARF1) GA receptors stimulates GID1-GA-DELLA complex formation which in turn triggers DELLA protein ubiq...

425

HEAT STRESS DURING EMBRYO DEVELOPMENT IMPAIRS SOYBEAN SEED GERMINATION AND VIGOR  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Early Soybean Production System (ESPS) has been applied to the Southern Central area in the U.S. to maintain soybean (Glycine max Merrill) yield by avoiding drought. However, ESPS can produce seeds with good compositional quality but low germination and vigor. Our hypothesis is that high tempera...

426

PHYTOTOXICITY OF MIMOSINE AND ALBIZZIINE ON SEED GERMINATION AND SEEDLING GROWTH.  

Technology Transfer Automated Retrieval System (TEKTRAN)

Mimosine and albizziine are two toxic, non-protein amino acids found in several legume species. Both compounds have been shown to inhibit seed germination and seedling growth, but no comparative study of the two compounds has been conducted. In the present study the 10-3 M concentration of both com...

427

Determination of Kinetic and Thermodynamic Parameters that Describe Isothermal Seed Germination: A Student Research Project.  

ERIC Educational Resources Information Center

Describes a project for students to collect and fit data to a theoretical mathematical model that describes the rate of isothermal seed germination, including activation energy for substrate and produce and the autocatalytic reaction, and changes in enthalpy, entropy, and the Gibb's free energy. (Author/SK)

Hageseth, Gaylord T.

1982-01-01

428

Novel hydrated graphene ribbon unexpectedly promotes aged seed germination and root differentiation  

NASA Astrophysics Data System (ADS)

It is well known that graphene (G) induces nanotoxicity towards living organisms. Here, a novel and biocompatible hydrated graphene ribbon (HGR) unexpectedly promoted aged (two years) seed germination. HGR formed at the normal temperature and pressure (120 days hydration), presented 17.1% oxygen, 0.9% nitrogen groups, disorder-layer structure, with 0.38 nm thickness ribbon morphology. Interestingly, there were bulges around the edges of HGR. Compared to G and graphene oxide (GO), HGR increased seed germination by 15% root differentiation between 52 and 59% and enhanced resistance to oxidative stress. The metabonomics analysis discovered that HGR upregulated carbohydrate, amino acid, and fatty acids metabolism that determined secondary metabolism, nitrogen sequestration, cell membrane integrity, permeability, and oxidation resistance. Hexadecanoic acid as a biomarker promoted root differentiation and increased the germination rate. Our discovery is a novel HGR that promotes aged seed germination, illustrates metabolic specificity among graphene-based materials, and inspires innovative concepts in the regulation of seed development.

Hu, Xiangang; Zhou, Qixing

2014-01-01

429

Allelopathic effects of sorghum extracts on Amaranthus retroflexus seed germination and growth  

Microsoft Academic Search

With regards to importance and abundance of Amaranthus retroflexus weed in fields an experiment was conducted using CRD based factorial design with three replications to study the allelopathic effects of sorghum extracts on germination and growth of Amaranthus retroflexus in 2008-2009. Treatments were: harvesting stage of extracted sorghum (vegetative, flowering and seed filling stage), extracted plant part (leaf, stem, root

M. Yarnia; M. B. Khorshidi Benam; E. Farajzadeh Memari Tabrizi

2009-01-01

430

Novel hydrated graphene ribbon unexpectedly promotes aged seed germination and root differentiation  

PubMed Central

It is well known that graphene (G) induces nanotoxicity towards living organisms. Here, a novel and biocompatible hydrated graphene ribbon (HGR) unexpectedly promoted aged (two years) seed germination. HGR formed at the normal temperature and pressure (120 days hydration), presented 17.1% oxygen, 0.9% nitrogen groups, disorder-layer structure, with 0.38?nm thickness ribbon morphology. Interestingly, there were bulges around the edges of HGR. Compared to G and graphene oxide (GO), HGR increased seed germination by 15% root differentiation between 52 and 59% and enhanced resistance to oxidative stress. The metabonomics analysis discovered that HGR upregulated carbohydrate, amino acid, and fatty acids metabolism that determined secondary metabolism, nitrogen sequestration, cell membrane integrity, permeability, and oxidation resistance. Hexadecanoic acid as a biomarker promoted root differentiation and increased the germination rate. Our discovery is a novel HGR that promotes aged seed germination, illustrates metabolic specificity among graphene-based materials, and inspires innovative concepts in the regulation of seed development. PMID:24445438

Hu, Xiangang; Zhou, Qixing

2014-01-01

431

EFFECTS OF XANTHIUM LEAF EXTRACTS ON LETTUCE SEED GERMINATION1' 2  

Microsoft Academic Search

Seed germination in lettuce var. Grand Rapids, and floral induction in Xanthium are phytochrome-mediated processes. The pigment conversion which triggers these two rather diverse developmental events appears to be essentially the same. The present work was conducted to test the possibility that secondary metabolic steps following the initial triggering phase might also be shared by these two morphological processes. Aqueous

DOUGLAS G. FRATIANNE

432

Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)  

Microsoft Academic Search

From our experiences, awl-fruit sedge (Carex stipata Muhl. ex Willd. [Cyperaceae]) is an easily propagated wetland plant in Washington State. Because seeds can be collected from the same growth year, germinated without stratification, and grown into plants, C. stipata can be quickly propagated during summer for fall and winter outplanting. We believed, however, that perigynium removal could improve success. We

Derrick D. Cooper; Nate Hough-Snee

2011-01-01

433

Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)  

Microsoft Academic Search

:From our experiences, awl-fruit sedge (Carex stipata Muhl. ex Willd. [Cyperaceae]) is an easily propagated wetland plant in Washington State. Because seeds can be collected from the same growth year, germinated without stratification, and grown into plants, C. stipata can be quickly propagated during summer for fall and winter outplanting. We believed, however, that perigynium removal could improve success. We

Derrick D. Cooper; Nate Hough-Snee

2011-01-01

434

Nitrogen effects on seed germination and seedling growth  

Microsoft Academic Search

Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experi- ments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 perennial grasses, blue- bunch

THOMAS A. MONACO; CHARLES T. MACKOWN; DOUGLAS A. JOHNSON; THOMAS A. JONES; JEANETTE M. NORTON; JAY B. NORTON; MARGARET G. REDINBAUGH

2003-01-01

435

[Effects of light intensity on Quercus liaotungensis seed germination and seedling growth].  

PubMed

This paper studied the effects of different shading (55.4%, 18.9%, 5.5%, 2.2%, 0.5% , and 0.3% natural sunlight) on the seed germination and seedling growth of Quercus liaotungensis. The seed germination rate and germination index were the highest (72.5% and 0.22, respectively) at 55.4% natural sunlight, declined with decreasing light intensity, and were the lowest (42.5% and 0.11, respectively) at 0.3% natural sunlight. Strong light had definite delaying effect on the germination. The index of germination vigor increased with decreasing light intensity, being the maximum at 0.5% natural sunlight. The delay of seed germination under strong light could be the selective tradeoff on varied seed fates. Strong light benefited the basal stem diameter and root system growth and dry mass accumulation of Q. liaotunensis seedling, but resulted in the minimum seedlings height (6.06 cm). Greater morphological plasticity was observed for the seedlings under different shading, which lent support to the higher adaptability of the seedlings to light environment. For example, the specific leaf area, specific shoot length, specific root length, and chlorophyll b and total chlorophyll contents were the maximum at 0.5% natural sunlight, being 142.57 cm2 x g(-1), 156.86 cm x g(-1), 271.87 cm x g(-1), 0.07 g x cm(-2), and 0.24 g x cm(-2), respectively, and the minimum at 55.4% natural sunlight, being 44.89 cm2 x g(-1), 52.84 cm x g(-1), 101.98 cm x g(-1), 0.04 g x cm(-2), and 0.15 g x cm(-2), respectively. The variation of the root/shoot ratio of Q. liaotungensis seedlings under different shading could be the effects of the combination of light intensity and water availability. PMID:22007441

Yan, Xing-fu; Wang, Jian-li; Zhou, Li-biao

2011-07-01

436

Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.  

PubMed

In order to investigation of allelopathic effects of some ornamental trees on seed germination of rye-grass (Lolium prenne) and tall fescue (Festuca arundinaceae), this experiment was conducted in a randomized complete block design with 3 replicates at the laboratory of Horticultural Sciences Department of Ferdowsi University of Mashhad, during 2008. In this research, we studied the effect of aqueous and hydro-alcoholic extracts of Afghanistan pine (Pinus eldarica), arizona cypress (Cupressus arizonica), black locust (Robinia psedue acacia) and box elder (Acer negundo) leaves that prepared in 1:5 ratio on seed germination percent and rate for two grasses. The results showed that all extracts decreased statistically seed germination in compared to control treatment. The highest germination percentage and germination rate of tested grass detected in control treatment. Hydro-alcoholic extracts of all woody plants (15, 30%) were completely inhibited seed germination of rye-grass and tall fescue. Also aqueous extract of arizona cypress was completely inhibited seed germination of tall fescue and had more inhibitory activity than other aqueous extracts on rye-grass. Between aqueous extracts, the highest and lowest seed germination of rye-grass was found in Afghanistan pine and arizona cypress, respectively. PMID:21313873

Arouiee, H; Nazdar, T; Mousavi, A

2010-11-01

437

Genotyping of Endosperms to Determine Seed Dormancy Genes Regulating Germination Through Embryonic, Endospermic, or Maternal Tissues in Rice  

PubMed Central

Seed dormancy is imposed by one or more of the embryo, endosperm, and maternal tissues that belong to two generations and represent two ploidy levels. Many quantitative trait loci (QTL) have been identified for seed dormancy as measured by gross effects on reduced germination rate or delayed germination in crop or model plants. This research developed an endosperm genotype?based genetic approach to determine specific tissues through which a mapped QTL regulates germination using rice as a model. This approach involves testing germination velocity for partially after-ripened seeds harvested from single plants heterozygous for a tested QTL and genotyping endosperms from individual germinated and nongerminated seeds with a codominant DNA marker located on the QTL peak region. Information collected about the QTL includes genotypic frequencies in germinated and/or nongerminated subpopulations; allelic frequency distributions during a germination period; endosperm or embryo genotypic differences in germination velocity; and genotypic frequencies for gametes involved in the double fertilization to form the sampled seeds. Using this approach, the seed dormancy loci SD12, SD1-2, and SD7-1 were determined to regulate germination through the embryo, endosperm, and maternal tissues, respectively; SD12 and SD1-2 acted additively on germination velocity in the offspring tissues; and SD12 also was associated with the preferential fertilization of male gametes in rice. This new genetic approach can be used to characterize mapped genes/QTL for tissue-specific functions in endospermic seeds and for marker-assisted selection of QTL alleles before or immediately after germination in crop breeding. PMID:25480961

Gu, Xing-You; Zhang, Jinfeng; Ye, Heng; Zhang, Lihua; Feng, Jiuhuan

2014-01-01

438

Water Relations of Seed Development and Germination in Muskmelon (Cucumis melo L.) 1  

PubMed Central

Total water potential (?), solute potential, and turgor potential of field-grown muskmelon (Cucumis melo L.) fruit tissue (pericarp) and seeds were determined by thermocouple psychrometry at 5-day intervals from 10 to 65 days after anthesis (DAA). Fruit maturity occurred between 44 and 49 DAA, and seed germination ability developed between 35 and 45 DAA. Pericarp ? was essentially constant at approximately ?0.75 megapascal (MPa) from 10 to 25 DAA, then decreased to a minimum value of ?1.89 MPa at 50 DAA before increasing to ?1.58 MPa at 65 DAA. Seed ? remained relatively constant at approximately ?0.5 MPa from 10 to 30 DAA then decreased to ?2.26 MPa at 50 to 60 DAA before increasing to ?2.01 MPa at 65 DAA. After a rapid increase to 20 DAA, seed fresh weight declined until 30 DAA due to net water loss, despite continuing dry weight gain. As fruit and seed growth rates decreased, turgor potential initially increased, then declined to small values when growth ceased. A disequilibrium in ? was measured between seeds and pericarp both early and late in development. From 20 to 40 DAA, the ? gradient was from the seed to the tissue, coinciding with water loss from the seeds. From 50 to 65 DAA, seed ? decreased, causing a reversal of the ? gradient and a slight increase in seed water content. The partitioning of solutes between symplast and apoplast may create and maintain ? gradients between the pericarp and seed. The low solute potential within the pericarp due to solute accumulation and loss of cellular compartmentation during ripening and sensecence may be involved in prevention of precocious germination of mature seeds. PMID:16665921

Welbaum, Gregory E.; Bradford, Kent J.

1988-01-01

439

The effect of ethylene, octanoic acid and a plant-derived smoke extract on the germination of light-sensitive lettuce seeds  

Microsoft Academic Search

The effects of an aqueous plant-derived smoke extract, octanoic acid and ethylene on germination of light-sensitive Grand Rapids lettuce seeds were investigated. The smoke extract brought about a concentration dependent increase in germination and a complete inhibition of germination at high concentrations. Octanoic acid could not induce germination. Ethylene at concentrations over 5 µL L-1 increased lettuce seed germination, but

A. K. Jäger; A. Strydom; J. Staden

1996-01-01

440

Germination of Acacia harpophylla (Brigalow) seeds in relation to soil water potential: implications for rehabilitation of a threatened ecosystem.  

PubMed

Initial soil water conditions play a critical role when seeding is the primary approach to revegetate post-mining areas. In some semi-arid climates, such as the Brigalow Belt Bioregion in eastern Australia, extensive areas are affected by open-cut mining. Together with erratic rainfall patterns and clayey soils, the Brigalow Belt denotes a unique biome which is representative of other water-limited ecosystems worldwide. Apart from other environmental stressors, germination is governed by the water potential of the surrounding soil material. While previous studies have confirmed the high tolerance of Brigalow (Acacia harpophylla) seeds to a broad range of temperature and salinity, the question of how soil water potential triggers seed germination remains. In this study, we used three replicates of 50 seeds of Brigalow to investigate germination in relation to water potential as an environmental stressor. Solutions of Polyethylene Glycol (PEG 6000) were applied to expose seeds to nine osmotic water potentials ranging from soil water saturation (0 MPa) and field capacity (-.01 to -.03 MPa) to the permanent wilting point (-1.5 MPa). We measured germinability (number of germinated seeds relative to total number of seeds per lot) and mean germination time (mean time required for maximum germination of a seed lot) to quantify germination. Based on the empirical data of the germination we estimated the parameters of the hydrotime model which simulates timing and success of seed emergence. Our findings indicate that Brigalow seeds are remarkably tolerant to water stress, with germination being observed at a water potential as low as -1.5 MPa. Likewise, the average base water potential of a seed population (hydrotime model) was very low and ranged between -1.533 and -1.451 MPa. In general, Brigalow seeds germinate opportunistically over a broad range of abiotic conditions related to temperature, salinity, and water availability. Direct seeding and