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1

The Effects of Bio-priming with PGPR on Germination of Radish (Raphanus sativus L.) Seeds under Saline Conditions  

Microsoft Academic Search

The present study was conducted to examine the effects of bio-priming with plant growth promoting rhizobacteria (PGPR) on the germination of radish (Raphanus sativus L.) seeds under different saline (NaCl) conditions. Three radish cultivars ('Antep', 'Beyaz', and 'Siyah') were used as plant material and 5 bacteria strains (Agrobacterium rubi strain A 16, Burkholderia gladii strain BA 7, Pseudomonas putida strain

Haluk Ça?lar KAYMAK; Faika YARALI; Mesude Figen DÖNMEZ

2

Comparison of antagonisms between abscisic acid and various growth stimulators during germination of barley and radish seeds  

Microsoft Academic Search

In this work, antagonism among abscisic acid preventing seedling growth and germination of barley and radish seeds and gibberellic acid, kinetin, benzyladenine, ethylene, brassinosteroid, triacontanol and polyamines (cadaverine, putrescine, spermidine, spermine) was studied. Although many stimulators mentioned were not able to overcome the radicle elongation- preventive effect of abscisic acid, the seeds reached 100% germination in this hormone medium. In

Kursat Cavusoglu; Kudret Kabar

2007-01-01

3

Comparative effects of some plant growth regulators on the germination of barley and radish seeds under high temperature stress  

Microsoft Academic Search

The effects of gibberellic acid, kinetin, benzyladenine, ethylene, 24-epibrassinolide, tri- acontanol and polyamines (cadaverine, putrescine, spermidine, spermine), alone or in combinations, on germination and early seedling growth under high temperature conditions of barley and radish seeds were studied. High temperature both delayed and inhibited the germinations of both the species. Only three of the single applications gibberellic acid, kinetin and

Kursat Cavusoglu; Kudret Kabar

2007-01-01

4

THE EFFECTS OF PRETREATMENTS OF SOME PLANT GROWTH REGULATORS ON GERMINATION AND SEEDLING GROWTH OF RADISH SEEDS UNDER SALINE CONDITIONS  

Microsoft Academic Search

The effects of gibberellic acid, kinetin, benzyladenine, ethylene, triacontanol, 24-epibrassinolide and polyamines (cadaverine, putrescine, spermidine, spermine), alone or in combinations, on seed germination and seedling growth (fresh weight, hypocotyl percentage, radicle and hypocotyl elongation) of radish under saline conditions were studied. Although many of the growth regulator pretreatments alone carried out in overcoming of the negative effect of 0.25 and

Kudret KABAR

5

Release of Reactive Oxygen Intermediates (Superoxide Radicals, Hydrogen Peroxide, and Hydroxyl Radicals) and Peroxidase in Germinating Radish Seeds Controlled by Light, Gibberellin, and Abscisic Acid1  

PubMed Central

Germination of radish (Raphanus sativus cv Eterna) seeds can be inhibited by far-red light (high-irradiance reaction of phytochrome) or abscisic acid (ABA). Gibberellic acid (GA3) restores full germination under far-red light. This experimental system was used to investigate the release of reactive oxygen intermediates (ROI) by seed coats and embryos during germination, utilizing the apoplastic oxidation of 2?,7?-dichlorofluorescin to fluorescent 2?,7?-dichlorofluorescein as an in vivo assay. Germination in darkness is accompanied by a steep rise in ROI release originating from the seed coat (living aleurone layer) as well as the embryo. At the same time as the inhibition of germination, far-red light and ABA inhibit ROI release in both seed parts and GA3 reverses this inhibition when initiating germination under far-red light. During the later stage of germination the seed coat also releases peroxidase with a time course affected by far-red light, ABA, and GA3. The participation of superoxide radicals, hydrogen peroxide, and hydroxyl radicals in ROI metabolism was demonstrated with specific in vivo assays. ROI production by germinating seeds represents an active, developmentally controlled physiological function, presumably for protecting the emerging seedling against attack by pathogens. PMID:11299341

Schopfer, Peter; Plachy, Claudia; Frahry, Gitta

2001-01-01

6

Effect of polyamines and guanidines on the growth, nitrogen assimilation and reserve mobilization in germinating radish seeds  

Microsoft Academic Search

Polyamines and guanidines enhanced the growth of radish seedlings grown in dark or light, irrespective of the supply of nitrogen. All the compounds inhibited ntirate reducatase and glutamine synthetase in the cotyledons of light-grown but not in dark-grown seeds. Nitrite reductase and glutamate dehydrogenase were not affected. Protease activity was enhanced by all the compounds in dark-as well as in

S. K. Srivastava; M. S. Kansara; S. M. Mungre

1985-01-01

7

Monitoring soybean seed germination by calorimetry  

Microsoft Academic Search

A method to monitor seed germination that combines isothermal calorimetry and imbibition measurements is reported. Individual\\u000a seeds of three cultivars of soybean seeds (A7636RG, Munasqa and DM5.8RR) and one of radish were used. Imbibition curves were\\u000a performed on individual seeds in a germination chamber at 25 °C. Calorimetric specific thermal power (p)–time (t) curves of germination were also obtained at 25 °C

Fanny I. Schabes; E. Elizabeth Sigstad

2011-01-01

8

Potential allelochemicals from Ruta graveolens L. and their action on radish seeds  

Microsoft Academic Search

An aqueous extract ofRuta graveolens L. (250 g\\/liter) was tested for its allelopathic activity in vitro on radish germination and radicle growth in light and darkness. It caused a delay in the onset and a decrease in the rate of germination (40%) in the light. The photoinhibition of germination was accompanied by an inhibition of water uptake into the seed.

G. Aliotta; G. Cafiero; V. De Feo; R. Sacchi

1994-01-01

9

Transformation of radish ( Raphanus sativus L.) via sonication and vacuum infiltration of germinated seeds with Agrobacterium harboring a group 3 LEA gene from B. napus  

Microsoft Academic Search

A protocol for producing transgenic radish (Raphanus sativus) was obtained by using both ultrasonic and vacuum infiltration assisted, Agrobacterium-mediated transformation. The Agrobacterium strain LBA4404 contained the binary vector pBI121-LEA (late embyogenesis abundant), which carried a Group 3 LEA gene, from Brassica napus. Among six combinations, Agrobacterium-mediated transformation assisted by a combination of 5-min sonication with 5-min vacuum infiltration resulted in

Byong-Jin Park; Zaochang Liu; Akira Kanno; Toshiaki Kameya

2005-01-01

10

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 16.4mg 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 (857pg/g DW) radish (536pg/g DW) and broccoli (439pg/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

11

Combination treatments for killing Escherichia coli O157:H7 on alfalfa, radish, broccoli, and mung bean seeds.  

PubMed

In this study, the effectiveness of prolonged dry-heat treatment (50 degrees C) alone or in combination with chemical treatments (1% oxalic acid, 0.03% phytic acid, 50% ethanol, electrolyzed acidic water, and electrolyzed alkaline water) in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, broccoli, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. Dry-heat treatment for 17 or 24 h alone could reduce E. coli O157:H7 numbers to below detectable levels in radish, broccoli, and alfalfa seeds, but was unable to reduce the pathogen numbers to below the detectable level in mung bean seeds. In addition, dry-heat treatment for 17 h plus sanitizer treatments were effective in greatly reducing pathogen populations on radish, broccoli, and alfalfa seeds, without compromising the quality of the sprouts, but these treatments did not eliminate the pathogen from radish and alfalfa seeds. Seventeen hours of dry heat followed by a 1.0-kGy dose of irradiation completely eliminated E. coli O157:H7 from radish and mung bean seeds, whereas only a minimum radiation dose of 0.25 kGy was required to completely eliminate the pathogen from broccoli and alfalfa seeds. Dry heat in combination with radiation doses of up to 1.0 kGy did not negatively impact the seed germination rate or length of alfalfa, broccoli, and radish seeds or the length of alfalfa, broccoli, and radish sprouts, but did decrease the length of mung bean sprouts. PMID:19343955

Bari, M L; Nei, D; Enomoto, K; Todoriki, S; Kawamoto, S

2009-03-01

12

?- and ?-Amylases in seed germination  

Microsoft Academic Search

During the first 24 h of germination of wheat seeds, starch is hydrolysed by free ?-amylase. In the next 24 h, some amount\\u000a of inactive form of ?-amylase is converted into active form and this together with ?-amylase synthesizedde novo brings about the hydrolysis of starch. The amount of ?-amylase is greater in seeds with embryo intact than with embryo

A. K. Goswami; M. K. Jain; B. Paul

1977-01-01

13

Inhibition of radish germination and root growth by coumarin and phenylpropanoids  

Microsoft Academic Search

Thirteen natural and synthetic phenylpropanoids as well as coumarin (2×104M) were tested for their biological activity on radish germination and subsequent root growth in light and darkness. Coumarin was the most potent inhibitor. With some exceptions, phenylpropanoids with a carboxylic group in the side chain inhibited root growth. Coumarin was formed spontaneously by photooxidation of 2-hydroxycinnamic acid. Microscopic observations of

G. Aliotta; G. Cafiero; A. Fiorentino; S. Strumia

1993-01-01

14

?-l-Arabinofuranosidase from Radish (Raphanus sativus L.) Seeds  

PubMed Central

An ?-l-arabinofuranosidase has been purified 1043-fold from radish (Raphanus sativus L.) seeds. The purified enzyme was a homogeneous glycoprotein consisting of a single polypeptide with an apparent molecular weight of 64,000 and an isoelectric point value of 4.7, as evidenced by denaturing gel electrophoresis and reversed-phase or size-exclusion high-performance liquid chromatography and isoelectric focusing. The enzyme characteristically catalyzes the hydrolysis of p-nitrophenyl ?-l-arabinofuranoside and p-nitrophenyl ?-d-xylopyranoside in a constant ratio (3:1) of the initial velocities at pH 4.5, whereas the corresponding ?-l-arabinopyranoside and ?-d-xylofuranoside are unsusceptible. The following evidence was provided to support that a single enzyme with one catalytic site was responsible for the specificity: (a) high purity of the enzyme preparation, (b) an invariable ratio of the activities toward the two substrates throughout the purification steps, (c) a parallelism of the activities in activation with bovine serum albumin and in heat inactivation of the enzyme as well as in the inhibition with heavy metal ions and sugars such as Hg2+, Ag+, l-arabino-(1?4)-lactone, and d-xylose, and (d) results of the mixed substrate kinetic analysis using the two substrates. The enzyme was shown to split off ?-l-arabinofuranosyl residues in sugar beet arabinan, soybean arabinan-4-galactan, and radish seed and leaf arabinogalactan proteins. Arabinose and xylose were released by the action of the enzyme on oat-spelt xylan. Synergistic action of ?-l-arabinofuranosidase and ?-d-galactosidase on radish seed arabinogalactan protein resulted in the extensive degradation of the carbohydrate moiety. Images Figure 2 PMID:16652973

Hata, Keishi; Tanaka, Mika; Tsumuraya, Yoichi; Hashimoto, Yohichi

1992-01-01

15

[Metabolic control of seed germination].  

PubMed

We have used proteomics to better characterize germination and early seedling vigor in sugarbeet. Our strategy includes (1) construction of proteome reference maps for dry and germinating seeds of a high-vigor reference seed lot; (2) investigation of the specific tissue accumulation of proteins (root, cotyledon, perisperm); (3) investigation of changes in protein expression profiles detected in the reference seed lot subjected to different vigor-modifying treatments, e.g. aging and/or priming. More than 1 000 sugarbeet seed proteins have been identified by LC/MS-MS mass spectrometry (albumins, globulins and glutelins have been analyzed separately). Due to the conservation of protein sequences and the quality of MS sequencing (more than 10 000 peptide sequences have been obtained), the success rate of protein identification was on the average of 80%. This is to our knowledge the best detailed proteome analysis ever carried out in seeds. The data allowed us to build a detailed metabolic chart of the sugarbeet seed, generating new insights into the molecular mechanisms determining the development of a new seedling. Also, the proteome of a seed-storage tissue as the perisperm is described for the first time. PMID:18980744

Catusse, Julie; Strub, Jean-Marc; Job, Claudette; Van Dorsselaer, Alain; Job, Dominique

2008-01-01

16

A chilling-insensitive stage in germination of a low-temperature-adapted radish, rat’s tail radish ( Raphanus sativus L.) cv. “Pakki-hood”  

Microsoft Academic Search

The rat’s tail radish (Raphanus sativus cv. “Pakki-hood”), cultivated in the northern part of Thailand, does not require low temperature for flower-bud initiation and shows high germinability even at low temperature. To analyze its characteristic temperature response, seedlings were subjected to a 3 day-chilling treatment at 0°C after a series of incubations for germination at 26°C which ranged from 3h

Kazunari Nomura; Ichitaro Endo; Akira Tateishi; Hiroaki Inoue; Kazuo Yoneda

2001-01-01

17

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

18

Proteomics of rice seed germination  

PubMed Central

Seed is a condensed form of plant. Under suitable environmental conditions, it can resume the metabolic activity from physiological quiescent status, and mobilize the reserves, biosynthesize new proteins, regenerate organelles, and cell membrane, eventually protrude the radicle and enter into seedling establishment. So far, how these activities are regulated in a coordinated and sequential manner is largely unknown. With the availability of more and more genome sequence information and the development of mass spectrometry (MS) technology, proteomics has been widely applied in analyzing the mechanisms of different biological processes, and proved to be very powerful. Regulation of rice seed germination is critical for rice cultivation. In recent years, a lot of proteomic studies have been conducted in exploring the gene expression regulation, reserves mobilization and metabolisms reactivation, which brings us new insights on the mechanisms of metabolism regulation during this process. Nevertheless, it also invokes a lot of questions. In this mini-review, we summarized the progress in the proteomic studies of rice seed germination. The current challenges and future perspectives were also discussed, which might be helpful for the following studies. PMID:23847647

He, Dongli; Yang, Pingfang

2013-01-01

19

Physicochemical changes of oat seeds during germination  

Microsoft Academic Search

The physicochemical properties of native and germinated oat seeds cultivated in China and their correlations were investigated. The growth curve during germination of oat seeds was described. The malt yield was 84% at the end of malting. The losses by removing of shoots and rootlets were the major cause of the total dry matter losses in the last 24h of

Binqiang Tian; Bijun Xie; John Shi; Jia Wu; Yan Cai; Tuoming Xu; Sophia Xue; Qianchun Deng

2010-01-01

20

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

21

Photoinduced Seed Germination of Oenothera biennis L  

PubMed Central

The postinduction period of Oenothera biennis L. seed germination was examined by temperature treatments. For all experiments, seeds received a standard 24 hour/24°C preinduction period and 12 hour/32°C photoinduction period. Germination is inhibited by postinduction temperatures above 32°C. When seeds are briefly incubated at 44°C and then transferred to 28°C, they germinate at a much lower percentage than 28°C controls. When thermally inhibited seeds are placed in the dark at 28°C for 20 hours, they can be promoted to germinate by a single pulse of red light. Seeds incubated at 12°C or below immediately after photoinduction enter a lag period in which they germinate slowly or not at all for a long time and then resume germination. The length of the lag period is exponentially related to the postinduction temperature. When seeds are incubated at a low temperature and then transferred to a warm temperature, they germinate much more rapidly than seeds not incubated at a low temperature. A model is proposed which is consistent with these and additional results. In the model, a germination promoter is irreversibly formed from a precursor and the synthesis of the precursor is favored at low temperatures and its degradation is favored at high temperatures. PMID:16665932

Ensminger, Peter A.; Ikuma, Hiroshi

1988-01-01

22

Oxygen requirement of germinating flax seeds  

NASA Astrophysics Data System (ADS)

Plant experiments in earth orbit are typically prepared on the ground and germinated in orbit to study gravity effects on the developing seedlings. Germination requires the breakdown of storage compounds, and this metabolism depends upon respiration, making oxygen one of the limiting factors in seed germination. In microgravity lack of run-off of excess water requires careful testing of water dispensation and oxygen availability. In preparation for a shuttle experiment (MICRO on STS-107) we studied germination and growth of flax ( Linum usitatissimum L.) seedlings in the developed hardware (Magnetic Field Chamber, MFC). We tested between four to 32 seeds per chamber (air volume = 14 mL) and after 36 h measured the root length. At 90 ?l O 2 per seed (32 seeds/chamber), the germination decreased from 94 to 69%, and the root length was reduced by 20%, compared to 8 seeds per chamber. Based on the percent germination and root length obtained in controlled gas mixtures between 3.6 and 21.6% O 2 we determined the lower limit of reliable germination to be 10 vol. % O 2 at atmospheric pressure. Although the oxygen available in the MFC's can support the intended number of seeds, the data show that seed storage and microgravity-related limitations may reduce germination.

Kuznetsov, Oleg A.; Hasenstein, K. H.

2003-05-01

23

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.

24

Corn Seed Germination and Vigor Following Freezing during Seed Development  

Microsoft Academic Search

The potential for an early autumn frost to reduce corn (Zea mays L.) seed quality is a concern for seed producers. This study evaluated the effect of freezing rate, freezing temperature (26, 211C) and duration (4, 6 h), ear attachment, and endosperm composition on seed germination and vigor (accelerated aging (AA) and cold test) during seed development and maturation of

James Woltz; Dennis M. TeKrony; Dennis B. Egli

2006-01-01

25

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

26

Photoinduced Seed Germination of Oenothera biennis L  

PubMed Central

General characteristics of light-induced germination of Oenothera biennis L. seeds were investigated at 24°C. During dark imbibition, seeds reached maximal respiration in 7 hours and maximal water content and photosensitivity in 24 hours. After dark imbibition of 24 hours, seeds required a long exposure (>36 hours) to red or white light for maximal germination. Two photoperiods (12 and 2 hours) separated by a period of darkness of 10 to 16 hours gave near maximal germination. For the two photoperiod regime, the first light potentiates a reversible phytochrome response by the second light. A 35°C treatment for 2 to 3 hours in the dark immediately prior or subsequent to 8 hours of light caused a higher percentage of germination. A 2 hour treatment at 35°C also potentiates a reversible phytochrome response. Halved seeds germinated at 100% in light or darkness indicating that the light requirement of the seeds is lost in the halving procedure. After-ripened seeds required less light and germinated more rapidly and at higher percentages than seeds tested shortly after maturation. PMID:16665824

Ensminger, Peter A.; Ikuma, Hiroshi

1987-01-01

27

Proteomics 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

K. Gallardo; C. Job; S. P. C. Groot; M. Puype; H. Demol; J. Vandekerckhove; D. Job

2003-01-01

28

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

29

Hybrid Seed Production of Radish (Raphanus sativus L.)  

Microsoft Academic Search

During recent years, a number of F1 hybrids have been developed in radish by public and private agencies across the world, due to the increasing craze for F1 hybrids. India is not far behind in the race. F1 hybrids have been found advantageous for earliness, high early and total yield, root quality, uniform root development, delayed pithiness, resistance to insect

Praveen K. Singh; S. K. Tripathi; K. V. Somani

2001-01-01

30

Lesquerella seed pretreatment to improve germination  

Microsoft Academic Search

Lesquerella fendleri is a potential oilseed crop. Seed dormancy, including light requirement, is common in many small-seeded species native to arid and semiarid environments, and may be a major contributor to stand establishment difficulties in Lesquerella. Gibberellic acid (GA3) and potassium nitrate (KNO3) in solutions of water have been shown to be effective moistening agents for improving germination and reducing

Naveen Puppala; James L Fowler

2003-01-01

31

Organic acids as seed germination inhibitors  

Microsoft Academic Search

Phytotoxicity of aromatic and aliphatic acids was tested by a wheat seed bioassay. Wheat seed germination was found to be influenced by the number of hydroxy and methoxy groups, the molecular position of single and double hydroxy groups, the length of the aliphatic chain, as well as by the pKa of the acid solutions. Orto and meta coumaric, ferulic and

A. Saviozzi; R. Riffaldi

1994-01-01

32

Oxidative signaling in seed germination and dormancy  

PubMed Central

Reactive Oxygen Species (ROS) play a key role in various events of seed life. In orthodox seeds, ROS are produced from embryogenesis to germination, i.e., in metabolically active cells, but also in quiescent dry tissues during after ripening and storage, owing various mechanisms depending on the seed moisture content. Although ROS have been up to now widely considered as detrimental to seeds, recent advances in plant physiology signaling pathways has lead to reconsider their role. ROS accumulation can therefore be also beneficial for seed germination and seedling growth by regulating cellular growth, ensuring a protection against pathogens or controlling the cell redox status. ROS probably also act as a positive signal in seed dormancy release. They interact with abscisic acid and gibberellins transduction pathway and are likely to control numerous transcription factors and properties of specific protein through their carbonylation. PMID:19513212

El-Maarouf-Bouteau, Hayat

2008-01-01

33

Amyl expression during wheat seed germination  

Microsoft Academic Search

The expression pattern of ?-Amyl, a gene coding for high-pI ?-amylase, has been studied during wheat (Triticum aestivum) seed germination using both Northern-blot and in situ hybridisation. At early stages of germination (24 h after imbibition) this gene was exclusively expressed in the scutellar epithelium. The expression in this tissue was transient and independent of GA3. At later stages of

Francisco J. Cejudo; María T. Cubo; David C. Baulcombe

1995-01-01

34

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

35

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

36

Seed biology and in vitro seed germination of Cypripedium.  

PubMed

Abstract 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

37

GERMINATION OF SEEDS OF AZADIRACHTA INDICA ENHANCED BY ENDOCARP REMOVAL  

Microsoft Academic Search

Seeds of Azadirachta indica A. Juss. were collected from trees in Haiti and the effect of pre-germination treatments were investigated in the laboratory at the Instituto Superior de Agricultura, Santiago, Dominican Republic. Soaking seeds in water for up to 3 days had no effect on germination. Removal of the endocarp improved germination significantly even when seeds were air-dried. Possible physiological

WILLIAM R. CHANEY; DOUGLAS M. KNUDSON

1988-01-01

38

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

39

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 germination by interference with gibberellin metabolism and apoplastic superoxide production required Issue on Seed Biology (Issue 1, 2012) Supplementary data #12;Inhibitory effect of myrigalone A on seed

Leubner, Gerhard

40

Effect of amending materials on growth of radish plant in salinized soil  

Microsoft Academic Search

The critical Na levels in soil which restricted seed germination and growth of radish, and effect of the amending materials on reducing the salinity hazard were determined by performing petri dish and pot experiments. The plants were grown in amended salinized soil in a phytotron for 21 days. Excess accumulation of Na in cells suppressed seed germination and plant growth.

G. Shokohifard; K. Sakagami; R. Hamada; S. Matsumoto

1989-01-01

41

Precision metering of germinated seeds  

E-print Network

viability test and analysis. 208 LIST OF FIGURES Figure Graphical representations of the two-parameter exponential distribution. Page 31 Final seed metering system design. Major parts of overall control system. 50 52 Schematic of the single file... for metering system tests. 151 26 27 28 29 30 31 Histograms of arrival time c. o. v. Histograms of arrival time skewness Histograms of arrival time kurtosis. Arrival time density functions. Histogram of TMPTM/TMER for run 7. Scatter plot of percent...

Elliot, Gregory Lawrence

2012-06-07

42

Effect of salicylic acid and salt on wheat seed germination  

Microsoft Academic Search

The effects of pretreatment with salicylic acid on wheat seed germination (Triticum aestivum L. cv. Roshan), lipid peroxidation, and superoxide dismutase, catalase, polyphenol oxidase, and peroxidase activity were studied under conditions of salt stress. Seeds treated with different concentrations of salicylic acid were used for measuring germination traits. Salt stress was induced by sodium chloride solution. Seeds were soaked in

Aria Dolatabadian; Seyed Ali Mohammad Modarres Sanavy; Mozafar Sharifi

2009-01-01

43

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

44

Hydrogen sulfide promotes wheat seed germination under osmotic stress  

Microsoft Academic Search

Effects of NaHS, H2S donor, on germination and antioxidant metabolism in wheat (Triticum aestivum L.) seeds under osmotic stress were investigated. With the enhancement of osmotic stress, which was mimicked by PEG-6000,\\u000a the seed germination dropped gradually. NaHS treatment could promote wheat seed germination against osmotic stress in a dose-dependent\\u000a manner; while Na+ and other sulfur-containing components, such as S2?,

H. Zhang; M. J. Wang; L. Y. Hu; S. H. Wang; K. D. Hu; L. J. Bao; J. P. Luo

2010-01-01

45

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

46

Preparative separation and purification of sulforaphene from radish seeds by high-speed countercurrent chromatography.  

PubMed

Sulforaphene, a kind of isothiocyanates, derived from glucoraphenin which is the important ingredient of radish (Raphanus sativus L.) seeds, has shown significant pharmacological activities. In this paper, the separation and purification of sulforaphene from radish seeds, was achieved by high-speed countercurrent chromatography (HSCCC). A two-phase solvent system consisted of n-hexane-ethyl acetate-methanol-water (35:100:35:100, v/v/v/v) was applied. The revolution speed of the separation column, flow rate of the mobile phase and separation temperature were 800 rpm, 2 ml/min and 30°C, respectively. From about 1000 mg amount of the crude plant extract, 249.4 mg of pure sulforaphene was obtained by one-step separation on a 280 ml HSCCC column. The purified sulforaphene was at a high purity of 96.9% and the mass recovery was more than 95%. The purity of sulforaphene was determined by HPLC analysis and its chemical structure was assessed by MS, (1)H NMR, (13)C NMR and DEPT-135 NMR. PMID:23122063

Kuang, Pengqun; Song, Dan; Yuan, Qipeng; Lv, Xinhua; Zhao, Di; Liang, Hao

2013-01-15

47

Germination of Redberry Juniper (Juniperus pinchotii) Seed in Western Texas  

Microsoft Academic Search

ABSTRACT , Weinvestigated germination\\/seedling emergencecharacteristics of redberry juniper (Juniperus pinchotii Sudw.) seeds harvested in December 1993 from 20 trees in the central Edwards Plateau and in December 1996 from 21 trees. Germination of seeds collected from raccoon (Procyon lotor) and ,bird (American robin [Turdus migratorius] and cedar waxwing [Bombycilla cedrorum]) feces in the northwestern Edwards Plateau in December 1996 were

Joseph L. Petersen; Darrell N. Ueckert; Charles A. Taylor; Keith R. Shaffer

48

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

49

The germination characteristics of Scrophularia marilandica L. (Scrophulariaceae) seeds  

Microsoft Academic Search

Investigations on seeds of Scrophularia marilandica L. were undertaken to determine their germination requirements. Seeds were collected from three naturally occurring sites\\u000a and one greenhouse-grown population in London, Ontario in September and October of 1997. Some were set to germinate immediately\\u000a after collection; others were stored in or on soil outside and\\/or under controlled laboratory conditions before testing. Germination\\u000a was

Robert E. Nurse; Paul B. Cavers

2008-01-01

50

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

51

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

52

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

53

Recovery and Germination of Grass Seeds Ingested by Cattle  

Microsoft Academic Search

Seeds of bluebunch wheatgrass (Psuedoroegneria spicata (Pursh) A. Love) and Sandberg bluegrass (Poa secunda Presl.) were fed to Holstein heifers in different amounts to investigate the effects of seed feeding level and seed size on the recovery and germinability of passed seed. Animals were fed 60,000, 30,000,15,000, and 7,500 seeds of each species. Passed seeds were recovered from dungcollected daily

Ferhat Gokbulak

2006-01-01

54

Improving seed germination of native perennial Phlox longifolia  

Microsoft Academic Search

Seeds of native species of perennial phlox often germinate poorly for producers of native plants. To determine seed treatments that might improve germination, we conducted a study on the native longleaf phlox (Phlox longifolia L. [Polemoniaceae]). Seed treatments included a 7 °C (45 °F) cold treatment, a 21 °C (70 °F) warm treatment, 10 or 20 ml\\/l liquid smoke, 1000

2009-01-01

55

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

56

Reduction of Insect Damage in Radish with Floating Row Covers  

Microsoft Academic Search

Radish (Raphanus sativus L.) is a short season direct seeded crop with multiple seedlings starting as soon as the ground has thawed to ensure continuous supply. Floating row covers can be used to protect crops from low temperature to stimulate germination and to exclude insect pests. There is a need to optimize the use of floating row covers for early

Djamila Rekika; Katrine A. Stewart; Guy Boivin; Sylvie Jenni

2008-01-01

57

Volatile metabolites controlling germination in buried weed seeds.  

PubMed

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 O(2) levels and production of volatile metabolites identified as acetaldehyde, ethanol, and acetone. The effectiveness of these compounds in reducing germination was dependent on O(2) levels. PMID:16658159

Holm, R E

1972-08-01

58

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

59

Seed dormancy and germination--emerging mechanisms and new hypotheses  

PubMed Central

Seed dormancy has played a significant role in adaptation and evolution of seed plants. While its biological significance is clear, molecular mechanisms underlying seed dormancy induction, maintenance and alleviation still remain elusive. Intensive efforts have been made to investigate gibberellin and abscisic acid metabolism in seeds, which greatly contributed to the current understanding of seed dormancy mechanisms. Other mechanisms, which might be independent of hormones, or specific to the seed dormancy pathway, are also emerging from genetic analysis of “seed dormancy mutants.” These studies suggest that chromatin remodeling through histone ubiquitination, methylation and acetylation, which could lead to transcription elongation or gene silencing, may play a significant role in seed dormancy regulation. Small interfering RNA and/or long non-coding RNA might be a trigger of epigenetic changes at the seed dormancy or germination loci, such as DELAY OF GERMINATION1. While new mechanisms are emerging from genetic studies of seed dormancy, novel hypotheses are also generated from seed germination studies with high throughput gene expression analysis. Recent studies on tissue-specific gene expression in tomato and Arabidopsis seeds, which suggested possible “mechanosensing” in the regulatory mechanisms, advanced our understanding of embryo-endosperm interaction and have potential to re-draw the traditional hypotheses or integrate them into a comprehensive scheme. The progress in basic seed science will enable knowledge translation, another frontier of research to be expanded for food and fuel production. PMID:24904627

Nonogaki, Hiroyuki

2014-01-01

60

Genome plasticity during seed germination in Festuca arundinacea  

Microsoft Academic Search

Feulgen\\/DNA cytophotometric determinations were carried out on early prophases in the meristems of seedlings obtained by\\u000a germinating seeds of different accessions of Festuca arundinacea at 10C, 20C, or 30C. Feulgen\\/DNA contents increased significantly with the increase in the temperature of seed germination.\\u000a In each accession, the greater the increase in absorption in seedlings obtained at 30C, the lower the absorption

M. Ceccarelli; T. Giordani; L. Natali; A. Cavallini; P. G. Cionini

1997-01-01

61

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

62

Reversal by pressure of seed germination promoted by anesthetics.  

PubMed

Germination of Panicum capillare L. caryopses induced by solutions of ethanol and ethyl ether was prevented by application of pressure >1 MPa during the period of exposure to the anesthetic. This effect of pressure indicates that germination is correlated with expansion at a site of anesthetic action in a cell membrane. The effects of several other anesthetics were measured on germination of P. capillare seeds. Ethanol, chloroform, and ethyl ether had the highest activity. Methanol and isopropanol were inactive. The effective compounds are thought to distribute preferentially to lipid-solution interfaces in cell membranes of the seeds. PMID:24306239

Hendricks, S B; Taylorson, R B

1980-07-01

63

Morphology, physiology and environmental effects of triploid watermelon seed germination  

E-print Network

HP5 Plus 400 negative film and contact prints were made. All photos were to be in black and white and were scanned using a Microtek ScanMaker III and enhanced using Photoshop 3. 0. Further observations were made on the same seed lots but by using... germination. They did improve germination with 1'/0 hydrogen peroxide solution and removing the seed coat and nicking also improved germination over the control. These experiments however were done on agar, and excess moisture from this media 36 could...

Grange, Stacie Lee

2012-06-07

64

Proteomic analysis of arabidopsis seed germination and priming.  

PubMed

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 radicle protrusion step. This approach was also used to analyze protein changes occurring during industrial seed pretreatments such as priming that accelerate seed germination and improve seedling uniformity. Several proteins were identified by matrix-assisted laser-desorption ionization time of flight mass spectrometry. Some of them had previously been shown to play a role during germination and/or priming in several plant species, a finding that underlines the usefulness of using Arabidopsis as a model system for molecular analysis of seed quality. Furthermore, the present study, carried out at the protein level, validates previous results obtained at the level of gene expression (e.g. from quantitation of differentially expressed mRNAs or analyses of promoter/reporter constructs). Finally, this approach revealed new proteins associated with the different phases of seed germination and priming. Some of them are involved either in the imbibition process of the seeds (such as an actin isoform or a WD-40 repeat protein) or in the seed dehydration process (e.g. cytosolic glyceraldehyde-3-phosphate dehydrogenase). These facts highlight the power of proteomics to unravel specific features of complex developmental processes such as germination and to detect protein markers that can be used to characterize seed vigor of commercial seed lots and to develop and monitor priming treatments. PMID:11402211

Gallardo, K; Job, C; Groot, S P; Puype, M; Demol, H; Vandekerckhove, J; Job, D

2001-06-01

65

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

66

Germination in seed species ingested by opossums: implications for seed dispersal and forest conservation  

Microsoft Academic Search

Seed germination in plant species consumed by oposs ums, genus Didelphis , was investigated in southern Brazil, in order to improve knowledge of the strategies of zoo chorous plants in the Neotropics. Seeds were obtain ed from opossum feces. Thirteen of the most frequent specie s in the diet of local opossums were tested for ger mination rates and germination

Nilton Carlos Cáceres; Emygdio Leite de Araújo Monteiro-Filho

2007-01-01

67

Seed germination and root elongation as indicators of exposure of wetland seedlings to metals  

SciTech Connect

Wetland ecosystems have often been impacted by the addition of hazardous waste materials. Methods are needed to evaluate the effect of these substances on wetland ecosystems and the organisms within them. This study evaluates the response of various wetland plant species to representative contaminants (cadmium, nickel, atrazine, anthracene, and tetrachloroethylene). Species tested include Caphalanthus occidentalis (buttonbush), Saururus cernuus (lizard`s tail), Liquidambar styraciflua (sweetgum), Sparganium americanum (bur-reed), and Fraxinus pennsylvanica (green ash). To the authors` knowledge these species have rarely if ever been used in toxicological assays. The endpoints used are germination and root elongation. Preliminary studies using a petri dish system have shown decreased germination at the highest metal concentration (50mg/L) and decreased root elongation in the higher metal concentrations (10, 25, and 50mg/L). Interference from the carrier was observed in the organic tests. Root elongation studies using the metals are being continued using tubes with various sand and vermiculite mixes into which freshly germinated seeds are placed. Species with the best responses will be tested in the field at the Savannah River Site, SC, and also with fuel oil. Lettuce (Lactuca saliva) and radish (Raphanus sativus) are being tested alongside the wetland species as reference organisms for which tests are well established.

Sutton, H.D.; Stokes, S.L.; Hook, D.D.; Klaine, S.J. [Clemson Univ., Pendleton, SC (United States)

1995-12-31

68

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, Valquiria A. Mendes; Toorop, Peter E.; Hilhorst, Henk W. M.

2007-01-01

69

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

70

Growth Enhancement of Radish Sprouts Induced by Low Pressure O2 Radio Frequency Discharge Plasma Irradiation  

NASA Astrophysics Data System (ADS)

We studied growth enhancement of radish sprouts (Raphanus sativus L.) induced by low pressure O2 radio frequency (RF) discharge plasma irradiation. The average length of radish sprouts cultivated for 7 days after O2 plasma irradiation is 30-60% greater than that without irradiation. O2 plasma irradiation does not affect seed germination. The experimental results reveal that oxygen related radicals strongly enhance growth, whereas ions and photons do not.

Kitazaki, Satoshi; Koga, Kazunori; Shiratani, Masaharu; Hayashi, Nobuya

2012-01-01

71

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

72

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

73

IAA production during germination of Orobanche spp. seeds  

Microsoft Academic Search

Broomrapes (Orobanche spp.) are parasitic plants, whose growth and development fully depend on the nutritional connection established between the parasite and the roots of the respective host plant. Phytohormones are known to play a role in establishing the specific Orobanche–host plant interaction.The first step in the interaction is seed germination triggered by a germination stimulant secreted by the host-plant roots.

Slavtcho Slavov; Henry van Onckelen; Rossitza Batchvarova; Atanas Atanassov; Els Prinsen

2004-01-01

74

Influence of fruit ripeness at the time of seed extraction on pepper ( Capsicum annuum) seed germination  

Microsoft Academic Search

The influence of fruit ripeness (half ripe, fully ripe, overripe) at the time of seed extraction on seed germination behaviour, at 25 °C and 13 °C, was studied in two Spanish pepper cultivars for canning. Seeds from half ripe fruits had a poorer behaviour than those taken from fully ripe fruits, especially at 13 °C. Room ripening and overripening of

Jose Cavero; Ramiro Gil Ortega; Carlos Zaragoza

1995-01-01

75

Intrapopulation variation in Abutilon theophrasti seed mass and its relationship to seed germinability  

Microsoft Academic Search

The relationship between seed mass variation and germinability in ten Abutilon theophrasti Medic. plants from a single agricultural population was examined under controlled environmental conditions. Seeds were collected in the autumn of 1995 and dry-stored in paper bags at 4°C until the start of trials in the spring of 1998. For each plant, between 549 and 1000 randomly selected seeds

Hameed A. Baloch; Antonio DiTommaso; Alan K. Watson

2001-01-01

76

Germination of yaupon (Ilex vomitoria Ait.) seed  

E-print Network

) observed that embryo development in yaupon was extremely slow. After 48 weeks the. embryo had developed only to the early cotyle- donary stage. Delay of germination in the American holly results from the mechanical resistance offered by the endocarp... after fruit coloration are not developed sufficiently for germination to occur. Immature embryos were first noted in American holly by ives (1923), The work of Jensen (1955) projected this develop, ental pattern to yaupon& and this work supports...

Fleming, Carl Michael

2012-06-07

77

Parasitoid attack of the seed-feeding beetle Bruchus loti enhances the germination success of Lathyrus japonicus seeds  

Microsoft Academic Search

Hard seeds of some legume species can germinate after seed-feeding insects bore through the seed coat and consequently break\\u000a seed dormancy. Larvae of bruchine beetles are the main seed feeders attacking many legume species. Boring of the hard seed\\u000a coat by bruchine beetle larvae enhances the germination percentage of legume species, but consuming too much of a single seed\\u000a may

Zenta NakaiTetsuya; Tetsuya Kondo; Shin-ichi Akimoto

78

Assessing the benefits of frugivory for seed germination: the importance of the deinhibition effect  

Microsoft Academic Search

Summary 1. Many studies have examined the effects of frugivores on the germination of seeds of fleshy fruited plants. However, three key issues are rarely addressed: the need to measure germination of seeds in intact fruits; the effect of germination conditions on results; and the distinction between dead vs dormant seeds. 2. A literature review including 51 plant species from

A. W. ROBERTSON; A. TRASS; J. J. LADLEY; D. KELLY

2006-01-01

79

Arabidopsis nudix hydrolase 7 plays a role in seed germination.  

PubMed

Arabidopsis nudix hydrolase 7 (Atnudt7) mutants exhibit reduced seed germination phenotype following after-ripening. The role of AtNUDT7 in seeds and during early stages of imbibition was examined. Seeds of Atnudt7-1 and Col-0 following 3 days of imbibition were used to profile changes in NADH- and ADP-ribose pyrophosphohydrolase enzyme activities, expression of nudix family genes closely related to AtNudt7, and AtNUDT7 protein levels. Changes in pyridine nucleotides, phytohormones, reactive oxygen species and poly(ADP-ribose) levels in after-ripened seeds and 1 day after imbibition were also analyzed. Changes in AtNUDT7 gene expression, protein levels and enzyme activities in WT seeds and during early stages of imbibition were correlated. Atnudt7-1 seeds lacked NADH pyrophosphohydrolase activity that led to very high catabolic redox charge. Abscisic acid (ABA) levels were higher in Atnudt7-1 mutant while salicylic acid, gibberellic acid, and reactive oxygen species (ROS) levels were higher in WT seeds. In Atnudt7-1, there was excess ROS accumulation 1 day after imbibition. PAR levels were significantly higher in Atnudt7-1 mutant when compared to WT during imbibition. Based on these observations, we conclude NADH pyrophosphohydrolase activity conferred by AtNUDT7 is important for NAD:NADH homeostasis in seeds. Perturbations to this key redox couple alter ABA and ROS levels in the seeds that in turn lowers germination. PMID:24504697

Zeng, Xin; Li, Yong-Fang; Mahalingam, Ramamurthy

2014-05-01

80

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

81

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

82

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

83

Ethylene in Seed Germination and Early Root Development  

Microsoft Academic Search

Seed germination is a model system for the analysis of plant development. Cell elongation and differentiation processes are under the control of hormones and submitted to the influence of environmental factors. Hormones (abscisic acid, auxin, gibberellic acid, ethylene and others) interact with each other as well as with diverse components of cell metabolism. Arabidopsis is the model system for the

Emilio Cervantes

84

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

85

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

E-print Network

(Fleming 1970). Scarification treatments are necessary to eliminate the effects of a hard seed coat. Scarification is either the removal or alteration of the seed coat to increase the absorption of oxygen and water. The presence of a hard seed coat may... to germinate. Second, internal conditions of the seed must be favorable for germination (i. e. physical and/or chemical barriers to germination must be absent). Third, the seed must be subjected to appropriate environmental conditions. Essential...

Whatley, Christopher Marc

2012-06-07

86

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

87

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

88

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, Jose R.

2014-01-01

89

Regulation of Avena Fatua Seed Germination by Smoke Solutions, Gibberellin A 3 and Ethylene  

Microsoft Academic Search

Dormant, intact Avena fatua L. (wild oat) seeds germinate poorly at 20 °C. Removing the hulls slightly increased germination. Treatment with smoke solutions\\u000a increased the germination of both intact seeds and caryopses. Exogenous GA3, alone or in the presence of smoke solution, increased the germination of caryopses, while ACC shows a tendency to increase\\u000a germination of caryopses only when applied in

J. K?pczy?ski; B. Bia?ecka; M. E. Light; J. van Staden

2006-01-01

90

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

91

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

92

[Infrared spectroscopic study on storage substance mobilization of crop seeds in germination].  

PubMed

The traditional method to study the storage substance mobilization of seeds during the process of germination is chemical extraction, which is troublesome and time consuming. In the present paper, Fourier transform infrared spectroscopy was used to study the storage substance mobilization of legume and cereal seeds in germination. The spectral results show that legume seeds (soybean, pea and broad bean) exhibit similar remarkable changes in the region from 1 000 to 1 200 cm(-1) in germination, which suggest that the storage carbohydrates in endosperm of legume seeds are mobilized during the process of germination. Notable changes were observed on amide bands of protein and lipid band in the spectra of germinating cereal seeds (rice, wheat and barley), indicating that storage proteins and lipids in cotyledon were utilized during the process of cereal seed germination. The results suggest that vibrational spectroscopy has the advantages of rapidress and convenience in the study of crop seeds and seed physiology. PMID:18422124

Liu, Gang; Tan, Li-Ping; Dong, Qin

2008-01-01

93

Protein mobilization in germinating mung bean seeds involves vacuolar sorting receptors and multivesicular bodies.  

PubMed

Plants accumulate and store proteins in protein storage vacuoles (PSVs) during seed development and maturation. Upon seed germination, these storage proteins are mobilized to provide nutrients for seedling growth. However, little is known about the molecular mechanisms of protein degradation during seed germination. Here we test the hypothesis that vacuolar sorting receptor (VSR) proteins play a role in mediating protein degradation in germinating seeds. We demonstrate that both VSR proteins and hydrolytic enzymes are synthesized de novo during mung bean (Vigna radiata) seed germination. Immunogold electron microscopy with VSR antibodies demonstrate that VSRs mainly locate to the peripheral membrane of multivesicular bodies (MVBs), presumably as recycling receptors in day 1 germinating seeds, but become internalized to the MVB lumen, presumably for degradation at day 3 germination. Chemical cross-linking and immunoprecipitation with VSR antibodies have identified the cysteine protease aleurain as a specific VSR-interacting protein in germinating seeds. Further confocal immunofluorescence and immunogold electron microscopy studies demonstrate that VSR and aleurain colocalize to MVBs as well as PSVs in germinating seeds. Thus, MVBs in germinating seeds exercise dual functions: as a storage compartment for proteases that are physically separated from PSVs in the mature seed and as an intermediate compartment for VSR-mediated delivery of proteases from the Golgi apparatus to the PSV for protein degradation during seed germination. PMID:17322331

Wang, Junqi; Li, Yubing; Lo, Sze Wan; Hillmer, Stefan; Sun, Samuel S M; Robinson, David G; Jiang, Liwen

2007-04-01

94

Thiamine binding and metabolism in germinating seeds of selected cereals and legumes  

Microsoft Academic Search

The basic characteristics of thiamine metabolism in germinating seeds of maize (Zea mays), oat (Avena sativa), faba bean (Vicia faba) and garden pea (Pisum sativum) are presented with a special emphasis of a possible thiamine storage function of seed thiamine-binding proteins (TBPs). Seeds were germinated for 6 d in the dark. Thiamine-binding activity in seeds decreased during germination by 50% in

Anna Go?da; Piotr Szyniarowski; Katarzyna Ostrowska; Andrzej Kozik; Maria R?pa?a-Kozik

2004-01-01

95

Responses of seed germination, seedling growth, and seed yield traits to seed pretreatment in maize (Zea mays L.).  

PubMed

A series of seed priming experiments were conducted to test the effects of different pretreatment methods to seed germination, seedling growth, and seed yield traits in maize (Zea mays L.). Results indicated that the seeds primed by gibberellins (GA), NaCl, and polyethylene glycol (PEG) reagents showed a higher imbibitions rate compared to those primed with water. The final germination percentage and germination rate varied with different reagents significantly (P < 0.05). The recommended prime reagents were GA at 10?mg/L, NaCl at 50?mM, and PEG at 15% on account of germination experiment. 15% PEG priming reagent increased shoot and root biomass of maize seedling. The shoot biomass of seedlings after presoaking the seeds with NaCl reagent was significantly higher than the seedlings without priming treatment. No significant differences of plant height, leaf number, and hundred-grain weight were observed between control group and priming treatments. Presoaking with water, NaCl (50?mM), or PEG (15%) significantly increased the hundred-grain weight of maize. Therefore, seed pretreatment is proved to be an effective technique to improve the germination performance, seedling growth, and seed yield of maize. However, when compared with the two methods, if immediate sowing is possible, presoaking is recommended to harvest better benefits compared to priming method. PMID:25093210

Tian, Yu; Guan, Bo; Zhou, Daowei; Yu, Junbao; Li, Guangdi; Lou, Yujie

2014-01-01

96

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

97

Seed germination and growth inhibitory cadinenes from Eupatorium adenophorum spreng  

Microsoft Academic Search

Chloroform extract of the aerial parts ofEupatorium adenophorum Spreng was fractionated and examined for growth inhibition. Bioassay-directed fractions of the plant materials afforded three known cadinenes and ?-sitosterol. The effects of different fractions as well as isolated cadinenes were determined usingAllium cepa, Raphanus sativus, andCucumis sativus seeds. Three-day exposure to these cadinenes significantly inhibited germination and seedling growth of all

Narayan C. Baruah; Jadab C. Sarma; Soneswar Sarma; Ram P. Sharma

1994-01-01

98

Improvement of caper ( Capparis spinosa L.) seed germination by breaking seed coat-induced dormancy  

Microsoft Academic Search

Different dormancy-breaking pretreatments were assessed in order to improve germination of caper (Capparis spinosa L.) seeds. High germination percentages were obtained using concentrated sulfuric acid, followed by either a 90-min soaking procedure in a 100 ppm gibberellin (GA4 + 7) solution, or adding 0.2% potassium nitrate to the test substrate. Results obtained by means of a surgical treatment clearly suggest

Gabriel O. Sozzi; Angel Chiesa

1995-01-01

99

In vitro germination and seedling development of cryopreserved Dendrobium hybrid mature seeds  

Microsoft Academic Search

In vitro germination and seedling development from Dendrobium Swartz. hybrid ‘Sena Red’, ‘Mini WRL’, ‘Jaquelyn Thomas’, and ‘BFC Pink’ seeds cryopreserved through vitrification (PVS2) were evaluated. Germination percentages after cryopreservation (LN) were variable among different controls and treatments, despite the initial high seed viability for all hybrids. Seeds exposed to PVS2 at ice temperature from 1 to 3h prior to

Wagner A. Vendrame; V. S. Carvalho; J. M. M. Dias

2007-01-01

100

Seed Development and Germination in an Arabidopsis thaliana Line Antisense to Glutathione Reductase 2  

Microsoft Academic Search

Desiccating and germinating seeds are particularly prone to oxidative stress. Glutathione (GSH) is one of the most abundant and ubiquitous antioxidants in plants. To better understand GSH's role in developing and germinating seeds, wildtype (WT) and a line of seed antisense for glutathione reductase 2 (anGR2), one of two glutathione reductase (GR) genes characterized in the genetic model plant Arabidopsis

M. R. Sumugat; J. L. Donahue; D. F. Cortes; V. K. Stromberg; R. Grene; V. Shulaev; G. E. Welbaum

2010-01-01

101

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

102

Teaching Through Trade Books: Secrets of Seeds  

NSDL National Science Digital Library

From a tiny radish seed to a giant coconut, seeds come in a multitude of shapes and sizes. They all share one amazing secret: the potential to grow into a new plant when conditions are right. In this month's column, students observe a variety of seeds, match seeds to the plants they grow into, explore what seeds need to germinate and grow, and design investigations with seeds.

Morgan, Emily; Ansberry, Karen

2009-02-01

103

Allelopathic effects of Juglone and decomposed walnut leaf juice on muskmelon and cucumber seed germination and seedling growth  

Microsoft Academic Search

In this study, effects of juglone and decomposed walnut leaf juice on muskmelon (Cucumis melo cv. Galia) and cucumber (Cucumis sativus cv. Beith Alpha) seed germination percentage and post- germination seedling growth were investigated. Decomposition was carried out by keeping the leaves in distilled water. Muskmelon and cucumber seeds were germinated in Petri dishes at 25°C. Seed germination, seedling elongation

I. Terzi

2008-01-01

104

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

105

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

PubMed

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. PMID:20428840

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

2010-06-01

106

Role of nano-SiO2 in germination of tomato (Lycopersicum esculentum seeds Mill.).  

PubMed

Agricultural biotechnology is very familiar with the properties of nanomaterial and their potential uses. Therefore, the present experiment was conducted to test the beneficial effects of nanosilicon dioxide (nSiO2: size- 12 nm) on the seed germination of tomato (Lycopersicum esculentum Mill. cv Super Strain B). Application of nSiO2 significantly enhanced the characteristics of seed germination. Among the treatments, 8 g L(-1) of nSiO2 improved percent seed germination, mean germination time, seed germination index, seed vigour index, seedling fresh weight and dry weight. Therefore, it is very clear that nSiO2 has a significant impact on the seed germination potential. These findings could provide that alternative source for fertilizer that may improve sustainable agriculture. PMID:24596495

Siddiqui, Manzer H; Al-Whaibi, Mohamed H

2014-01-01

107

Role of nano-SiO2 in germination of tomato (Lycopersicum esculentum seeds Mill.)  

PubMed Central

Agricultural biotechnology is very familiar with the properties of nanomaterial and their potential uses. Therefore, the present experiment was conducted to test the beneficial effects of nanosilicon dioxide (nSiO2: size- 12 nm) on the seed germination of tomato (Lycopersicum esculentum Mill. cv Super Strain B). Application of nSiO2 significantly enhanced the characteristics of seed germination. Among the treatments, 8 g L?1 of nSiO2 improved percent seed germination, mean germination time, seed germination index, seed vigour index, seedling fresh weight and dry weight. Therefore, it is very clear that nSiO2 has a significant impact on the seed germination potential. These findings could provide that alternative source for fertilizer that may improve sustainable agriculture. PMID:24596495

Siddiqui, Manzer H.; Al-Whaibi, Mohamed H.

2013-01-01

108

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

109

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

110

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

111

Improved germination of pansy seed at high temperatures by priming with salt solutions  

E-print Network

C12 showed better 31 germination than the seeds primed in PEG 8000 (Table 4). Similar result was reported in rudbeckia. Fay et al. (1994) reported that priming the seeds in PEG 8000 rather than KNO3 generally resulted in lower total germination...C12 showed better 31 germination than the seeds primed in PEG 8000 (Table 4). Similar result was reported in rudbeckia. Fay et al. (1994) reported that priming the seeds in PEG 8000 rather than KNO3 generally resulted in lower total germination...

Yoon, Beyoung-Han

2012-06-07

112

Mechanism and control of Genipa americana seed germination.  

PubMed

Genipa americana (Rubiaceae) is important for restoration of riparian forest in the Brazilian Cerrado. The objective was to characterize the mechanism and control of germination of G. americana to support uniform seedling production. Morphology and morphometrics of seeds, embryo and endosperm were assessed by light and scanning electron microscopy during germination. Imbibition and germination curves were generated and over the same time interval endosperm digestion and resistance were measured by puncture force analysis and activity assay of endo-?-mannanase (EBM) in water and in abscisic acid (ABA). The gene encoding for EBM was partially cloned and its expression monitored by quantitative real-time-polymerase chain reaction. Embryos displayed growth prior to radicle protrusion. A two-phase increase in EBM activity coincided with the two stages of weakening of the micropylar endosperm. The second stage also coincided with growth of the embryo prior to radicle protrusion. Enzyme activity was initiated in the micropylar endosperm but spread to the lateral endosperm. ABA completely inhibited germination by inhibiting embryo growth, the second stage of weakening and expression of the EBM gene, but EBM activity was not significantly inhibited. This suggests that a specific isoform of the enzyme is involved in endosperm weakening. EBM may cause a general 'softening' of micropylar endosperm cell walls, allowing the embryo to puncture the endosperm as the driving force of the decrease in puncture force. PMID:22150432

Queiroz, Sue Ellen Ester; da Silva, Edvaldo Aparecido Amaral; Davide, Antonio Claudio; José, Anderson Cleiton; Silva, Anderson Tadeu; Fraiz, Ana Carla Resende; Faria, José Marcio Rocha; Hilhorst, Henk W M

2012-03-01

113

Temperature effects on seed germination and expression of seed dormancy in wheat  

Microsoft Academic Search

Because preharvest sprouting decreases quantity and quality of wheat grain, researchers need effective protocols to assess\\u000a response to preharvest sprouting conditions. The aim of this study was to determine which temperature gives the greatest difference\\u000a in seed germination and expression of seed dormancy in 10 spring wheat genotypes. The genotypes were grown in the field near\\u000a Swift Current, Saskatchewan in

J. M. Nyachiro; F. R. Clarke; R. M. DePauw; R. E. Knox; K. C. Armstrong

2002-01-01

114

Seed germination regulation and field seed bank carryover in shadscale ( Atriplex confertifolia : Chenopodiaceae)  

Microsoft Academic Search

In laboratory germination studies with 15 collections ofAtriplex confertifolia, a dominant shrub of North American salt deserts, we found that seeds were dormant and largely unresponsive to chilling at dispersal but became chilling-responsive through dry after-ripening. Collections from warm desert habitats were more chilling-responsive and after-ripened more rapidly than those from cold desert habitats. In a field seed bank experiment,

Susan E. Meyer; Stephanie L. Carlson; Susan C. Garvin

1998-01-01

115

Influence of Seed Depth and Pathogens on Fatal Germination of Velvetleaf (Abutilon theophrasti) and Giant Foxtail (Setaria faberi)  

Microsoft Academic Search

Fatal germination of weed seeds occurs when a weed seed germinates, but the seedling dies before reaching the soil surface. Controlled-environment bioassays of velvetleaf and giant foxtail seed fate in Michigan field soil (Kalamazoo silt loam, 1.1% soil organic matter) were used to determine the role of pathogenic fungi and seed burial depth in fatal germination of these species. Fatal

Adam S. Davis; Karen A. Renner

2007-01-01

116

Seed germination ecology of the summer annual Cyperus squarrosus in an unpredictable mudflat habitat  

NASA Astrophysics Data System (ADS)

The purpose of our study was to better understand seed germination ecology of the summer annual sedge Cyperus squarrosus, which grows in various habitats, including mudflats and shallow soil over limestone bedrock (rock outcrops), where timing of the period favorable for germination and completion of the life cycle is unpredictable. Over a 28.5-month period, temperature and light:dark requirements for germination were determined at monthly intervals for seeds collected from mudflats and buried under flooded and under nonflooded conditions at natural temperature regimes. Data on dormancy and germination were compared to those published for seeds collected from plants growing on rock outcrops. Under both flooded and nonflooded conditions, seeds from mudflats exhibited an annual conditional dormancy/nondormancy cycle, similar to those from rock outcrops buried under nonflooded conditions. Seeds from mudflats germinated to higher percentages at mid-summer temperatures (35/20 °C) in mid-summer than those from rock outcrops. On the other hand, seeds from rock outcrops germinated to higher percentages at March temperatures (15/6 °C) in March than those from mudflats. Thus, seeds could germinate on mudflats any time from April through September if dewatering occurred, and they could germinate on rock outcrops any time from March through June and in September if soil moisture was nonlimiting; in both habitats light would be required for germination. Since seeds on mudflats may be flooded for several consecutive years, mudflats are more unpredictable than rock outcrops. Ability of seeds from mudflats to germinate to high percentages in light at 35/20 °C throughout the summer and those from rock outcrops not to do so may be related to the greater unpredictability of the mudflat. Each year for 11 years, seeds germinated in mudflat soil samples kept in a nonheated greenhouse, reaching a total of 22526 ± 1401 (mean ± S.E.) seeds m -2; thus, the species has the potential to form a large long-lived persistent soil seed bank.

Baskin, Carol C.; Baskin, Jerry M.; Chester, Edward W.

2004-07-01

117

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

118

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

2012-06-07

119

Methods toward improving 'Grande Rio 66' pepper seed germination  

E-print Network

; averaged from four replications of 50 seeds each for 14 days. z Treatment 5 6 7 Days from Placement in Petri Dishes 8 9 10 11 12 13 14 Ethyl Alcohol + Distilled Water Distilled Water Gibberellic Acid Indoleacetic Acid Kinetin Nicotinic Acid... of the IAA treatment can probably be attributed to the alcohol as in the previous experiment. With regard to earliness and total per cent germination, the 250 ppm solution of GA3 elicited a better response than did the 25 ppm solution. As ment1oned...

Rogers, Barbara Anna

2012-06-07

120

Inhibition by Fusicoccin of Germination of Pea Seeds 1  

PubMed Central

Fusicoccin inhibits the germination of pea (Pisum sativum L. cv Progress 9) seeds by decreasing the growth of the embryonal axis and by stimulating the fresh weight increase of the cotyledons. The growth of isolated embryonal axes in the presence of sucrose and KCl is stimulated by fusicoccin. The effect of fusicoccin on the seeds is not counteracted by sucrose and KCl. Fusicoccin promotes preferentially in the cotyledons a hyperpolarization of the transmembrane electric potential and an increase in the uptake capacity, suggesting the reinforcement of the sink strength of the cotyledons in comparison with the one of the embryonal axis and therefore the inhibition of translocation from the cotyledons of some substance necessary for the growth of the embryonal axis. PMID:16663930

Lioi, Lucia; Petruzzelli, Luciana; Morgutti, Silvia; Cocucci, Sergio M.

1984-01-01

121

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

122

Survival and germination of Mediterranean grassland species after simulated sheep ingestion: ecological correlates with seed traits  

NASA Astrophysics Data System (ADS)

Large amounts of viable seeds from Mediterranean grassland species have been found in herbivore dung; however which species produce seeds that can survive and germinate after ingestion by herbivores is still not well understood. This paper evaluates the importance of seed size, shape and coat impermeability in the endozoochorous dispersal process of 20 abundant species from central Iberian rangelands. Seed survival, germination percentages and germination speed were analysed in controlled experiments on the chewing and gut passage process by inserting seeds in the rumen of fistulated sheep, followed by simulated acid-pepsin digestion. Higher germination percentages in the control than the simulated sheep ingestion treatment were found in 75% of seeds. All species showed lower survival following the treatment, two species had a higher germination speed and five had a lower rate. Large-seeded species generally had higher survival percentages than small-seeded species. Species with impermeable seed coats had higher germination percentages following treatment although no significant differences were noted for either seed survival or germination speed.

Peco, B.; Lopez-Merino, L.; Alvir, M.

2006-09-01

123

Promotive Effects of Organic Solvents and Kinetin on Dark Germination of Lettuce Seeds 12  

PubMed Central

Significant promotion in dark germination was observed when Grand Rapids lettuce (Lactuca sativa L.) seeds were soaked in acetone or dichloromethane, vacuum-dried, and imbibed at 25 C. Permeation of kinetin via these organic solvents further enhanced the dark germination. Those seeds that were affected by acetone and acetone-kinetin treatments and germinated in the dark escaped red-far red photocontrol of germination. Although abscisic acid was not detected in the organic solvent leachates, they did contain other inhibitory substances affecting lettuce seedling growth. In the light, acetone and acetone-kinetin treatments also enhanced the rate of germination and the increased germination by acetone-kinetin treatment was correlated with increased polyribosome formation. The possible mechanisms involved in promotion of lettuce seed germination by organic solvents and kinetin are discussed. PMID:16659500

Rao, V. Sivaji; Braun, Joseph W.; Khan, Anwar A.

1976-01-01

124

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

125

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

126

EFFECTS OF ALUMINIUM (Al 3+ ) ON SEED GERMINATION AND SEEDLING GROWTH OF WHEAT (TRITICUM AESTIVUM L.)  

Microsoft Academic Search

Effects of different concentrations of aluminium (Al 3+ ) on seed germination of high yielding varieties of wheat (Triticum aestivum L.) were investigated. Al 3+ at 500 ppm had inhibitory effect on seed germination, seedling growth and its dry matter. Relatively higher root and shoot dry matter in Sonlika, Fang-60 and lower in Baw-923 and Protiva were found. Root growth

A. N. M. ALAMGIR; SUFIA AKHTER

2009-01-01

127

Crude extract of Astragalus mongholicus root inhibits crop seed germination and soil nitrifying activity  

Microsoft Academic Search

Astragalus mongholicus has been of medicinal use within the traditional Chinese system for centuries. However, little information is available on its allelopathic effects on other crop plants and soil biochemical properties. Field experiment showed that the extracted residues of A. mongholicus root inhibited seed germination of wheat. Inhibition of seed germination was further confirmed in laboratory using the same crude

Jian Mao; Linzhang Yang; Yuming Shi; Jian Hu; Zhe Piao; Lijuan Mei; Shixue Yin

2006-01-01

128

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

129

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

130

Morpho-anatomy, imbibition, viability and germination of the seed of Anadenanthera colubrina var. cebil (Fabaceae).  

PubMed

Seed biology is a relevant aspect of tropical forests because it is central to the understanding of processes of plant establishment, succession and natural regeneration. Anadenanthera colubrina var. cebil is a timber tree from South America that produces large seeds with thin weak teguments, which is uncommon among legumes. This study describes the morphology and anatomy of the seed coat, the viability, imbibition, and germination in this species. Seeds used during the essays came from 10 trees that grow naturally in Horco Molle, province of Tucumán, Argentina. Seed morphology was described from a sample of 20 units. The seed coat surface was examined with a scanning electron microscope. Transverse sections of hydrated and non-hydrated seeds were employed to describe the histological structure of the seed coat. Hydration, viability and germination experiments were performed under laboratory controlled conditions; and the experimental design consisted of 10 replicas of 10 seeds each. Viability and germination tests were conducted using freshly fallen seeds and seeds stored for five months. Morphologically the seeds of A. colubrina var. cebil are circular to subcircular, laterally compressed, smooth, bright brown and have a horseshoe fissure line (= pleurogram) on both sides. The seed coat comprises five tissue layers and a double (external and internal) cuticle. The outer cuticle (on the epidermis) is smooth and interrupted by microcracks and pores of variable depth. The epidermis consists of macroesclereids with non-lignified secondary walls. This layer is separated from the underlying ones during seed hydration. The other layers of internal tissues are comprised of osteosclereids, parenchyma, osteosclereids, and macrosclereids. The percentage of viable seeds was 93%, decreasing to 75% in seeds with five months old. Seed mass increased 76% after the first eight hours of hydration. Germination percentage was 75% after 76 hours. Germination of seeds stored for five months decreased to 12%. The results showed that seeds of A. colubrina var. cebil are highly permeable and germinate directly without a dormant period. PMID:24027911

Varela, Rodolfo Omar; Albornoz, Patricia Liliana

2013-09-01

131

Germination enhancement and inhibition of Distichlis spicata and Scirpus robustus seeds from Viriginia  

Microsoft Academic Search

Germination of mature, viable seeds ofDistichlis spicata (L.) Greene. andScirpus robustus Pursh. from two Virginia salt marshes was not significantly inhibited by aqueous washings from the rhizospheres of sand-culturedPhragmites australis (Cav.) Trin. ex. Stend.,Juncus roemerianus Scheele, orTypha angustifolia L. Germination ofS. robustus seed was inhibited by increased osmotic pressure whileD. spicata germination increased (2.5 fold) significantly when treated with leachate

J. E. Drifmeyer; J. C. Zieman

1979-01-01

132

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

E-print Network

availability is limiting. Introduction During seed imbibition, the quiescent dry seeds rapidly resume metabolic (group I) are more sensitive to O2 deprivation than are seeds with high starch content (group IIQuantifying the oxygen sensitivity of seed germination using a population-based threshold model

Bradford, Kent

133

Effects of development, temperature, and calcium hypochlorite treatment on in vitro germinability of Phalaenopsis seeds  

Microsoft Academic Search

There are no standardized procedures for sanitizing orchid seeds for propagation by tissue culture and there is insufficient information about the optimum stage of orchid seed development for best germination. Phalaenopsis amabilis flowers were hand-pollinated and fruits harvested 90, 105, and 120 d after pollination (DAP) for seed developmental analysis. Embryo cell number per seed was counted after staining with

A. M. Mweetwa; G. E. Welbaum; D. Tay

2008-01-01

134

Effect of passage through duck gut on germination of fennel pondweed seeds  

Microsoft Academic Search

Vertebrates are important seed dispersers for many plants. In addition to transport of seeds, ingestion often affects the proportion or rate of seed germination. We present one of the first studies comparing the effects of different waterbird species on the seeds of a subcosmopolitan pondweed, Potamogeton pectinatus. We also present the first comparison of the effects of digestion by ducks

Luis Santamaría; Iris Charalambidou; Jordi Figuerola; Andy J. Green

2002-01-01

135

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

136

Potato seed germination as influenced by food blender injury, gibberellic acid, thiram and fermentation  

Microsoft Academic Search

Summary  Three experiments were conducted in petri dishes and\\/or soil to study certain factors affecting germination of new and year\\u000a old potato seeds. The results were as follows:\\u000a \\u000a \\u000a 1. \\u000a \\u000a Germination from year old seed in both petri dishes and soil was reduced if blending time during seed extraction exceeded\\u000a 22 seconds.\\u000a \\u000a \\u000a \\u000a \\u000a 2. \\u000a \\u000a Germination of new seed in petri dishes was increased

F. I. Lauer; R. Mullin; A. W. Blomquist

1965-01-01

137

Gene expression programs during Brassica oleracea seed maturation, osmopriming, and germination are indicators of progression of the germination process and the stress tolerance level.  

PubMed

During seed maturation and germination, major changes in physiological status, gene expression, and metabolic events take place. Using chlorophyll sorting, osmopriming, and different drying regimes, Brassica oleracea seed lots of different maturity, stress tolerance, and germination behavior were created. Through careful physiological analysis of these seed lots combined with gene expression analysis using a dedicated cDNA microarray, gene expression could be correlated to physiological processes that occurred within the seeds. In addition, gene expression was studied during early stages of seed germination, prior to radicle emergence, since very little detailed information of gene expression during this process is available. During seed maturation expression of many known seed maturation genes, such as late-embryogenesis abundant or storage-compound genes, was high. Notably, a small but distinct subgroup of the maturation genes was found to correlate to seed stress tolerance in osmoprimed and dried seeds. Expression of these genes rapidly declined during priming and/or germination in water. The majority of the genes on the microarray were up-regulated during osmopriming and during germination on water, confirming the hypothesis that during osmopriming, germination-related processes are initiated. Finally, a large group of genes was up-regulated during germination on water, but not during osmopriming. These represent genes that are specific to germination in water. Germination-related gene expression was found to be partially reversible by physiological treatments such as slow drying of osmoprimed seeds. This correlated to the ability of seeds to withstand stress. PMID:15618428

Soeda, Yasutaka; Konings, Maurice C J M; Vorst, Oscar; van Houwelingen, Adele M M L; Stoopen, Geert M; Maliepaard, Chris A; Kodde, Jan; Bino, Raoul J; Groot, Steven P C; van der Geest, Apolonia H M

2005-01-01

138

Germination Responses to Water Potential in Neotropical Pioneers Suggest Large-seeded Species Take More Risks  

PubMed Central

Background and Aims In neotropical forests, very small-seeded pioneer species (<0·1 mg seed mass) recruit preferentially in small tree fall gaps and at gap edges, but large-seeded pioneers do not. Since water availability is related to gap size, these differences in microsite preference may reflect in part species-specific differences in germination at reduced water potentials. Methods For 14 neotropical pioneer species, the hypothesis is tested that small-seeded species, with shallow initial rooting depths, reduce the risks associated with desiccation by germinating more slowly and at higher water potentials than large-seeded species. Key Results Germination occurred both more quickly and at lower water potentials with increasing seed mass. For example, Ochroma pyramidale (seed mass 5·5 mg) had a time to 50 % germination (T50) of 2·8 d and a median base potential for germination (?b50) of ?1·8 MPa while Clidemia quinquenervia (seed mass 0·017 mg) had a T50 of 17·6 d and ?b50 of ?1·1 MPa. Conclusions These data suggest that small-seeded species germinate only in comparatively moist microsites, such as small canopy gaps, which may reduce the risk of drought-induced mortality. Conversely, large-seeded species are able to germinate in the drier environment of large gaps, where they benefit by enhanced seedling growth in a high irradiance environment. The positive association of seed size and canopy gap size for optimal seedling establishment is maintained by differential germination responses to soil water availability coupled with the scaling of radicle growth rate and seed size, which collectively confer greater drought tolerance on large-seeded species. PMID:18840874

Daws, Matthew I.; Crabtree, Lora M.; Dalling, James W.; Mullins, Christopher E.; Burslem, David F. R. P.

2008-01-01

139

Effects of seed burial on germination, protein mobilisation and seedling survival in Dodonaea viscosa.  

PubMed

Ecological restoration of disturbed areas requires substantial knowledge of the germination of native plants and the creation of novel methods to increase seedling establishment in the field. We studied the effects of soil matrix priming on the germination of Dodonaea viscosa seeds, which exhibit physical dormancy. To this end, we buried both pre-scarified (in H2SO4, 3 min) and non-pre-scarified seeds in the Parque Ecológico de la Ciudad de México. After seeds were unearthed, they were post-scarified for 0, 2, 6 and 10 min and their germination percentages compared to the germination of a control batch of laboratory-stored seeds. For both control and unearthed seeds, the protein pattern was determined in the enriched storage protein fraction in SDS-PAGE gels stained with Coomassie blue. Percentage germination increased as the scarification time increased. Pre-scarification significantly increased percentage germination of post-scarified seeds in relation to the control and non-pre-scarified seeds. In seeds unearthed from the forest site, the buried pre-scarified seeds had relatively high percentage germination, even in the absence of post-scarification treatment. A 48-kDa protein was not found in unearthed, pre-scarified seeds nor in the control germinated seeds, indicating that mobilisation of this protein occurred during soil priming. Burying seeds for a short period, including the beginning of the rainy season, promoted natural priming, which increased protein mobilisation. Functionally, priming effects were reflected in high percentage seedling survival in both the shade house and the field. Seed burial also reduced the requirement for acidic post-scarification. PMID:24148161

Benítez-Rodríguez, L; Gamboa-deBuen, A; Sánchez-Coronado, M E; Alvarado-López, S; Soriano, D; Méndez, I; Vázquez-Santana, S; Carabias-Lillo, J; Mendoza, A; Orozco-Segovia, A

2014-07-01

140

Seed fate in the myrmecochorous Neotropical plant Turnera ulmifolia L., from plant to germination  

NASA Astrophysics Data System (ADS)

Myrmecochory (seed dispersal by ants) differs from other dispersal systems in a series of advantages offered by the ants to the plants. Here, seed fate, from fruit to germination, of the myrmecochorous Neotropical plant Turnera ulmifolia L. is described. Seed movement from the fruit to their germination was studied, using different measurements and experiments. The results show that a T. ulmifolia individual produces ca. 5000 seeds per year. The main pre-seed-fall predators are the larvae of the Microlepidopteran Crocidosema plebejana Zeller, which consumed 1% of the seeds on the plant. The red-land crab Gecarcinus lateralis (Freminville) consumed 19% of the seeds beneath the plant and was the main post-seed-fall predator. Seed removal by ants was recorded on and beneath the plant, and ants removed 49% of the total seed production. Considering the seed removal events, the ant Forelius analis contributed with 64% of the total number of events. F. analis took seeds to its nest and discarded 23% of the seeds collected. Germination of seeds collected by F. analis was two to four times higher than that of seeds with and without elaiosome, respectively. The relatively low seed predation was probably related to ant defense, associated with the presence of extrafloral nectaries in this plant and with seed removal on the plant. Our results suggest that F. analis is a quantitatively efficient but qualitatively inefficient seed disperser of T. ulmifolia.

Salazar-Rojas, Betzabeth; Rico-Gray, Víctor; Canto, Azucena; Cuautle, Mariana

2012-04-01

141

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

142

Protective roles of nitric oxide on germination and antioxidant metabolism in wheat seeds under copper stress  

Microsoft Academic Search

Nitric oxide (NO) is a multifunctional gaseous signal in plant. In the present study, we found that pretreatment with NO could\\u000a significantly improve wheat seeds germination and alleviate oxidative stress against copper toxicity. With the enhancement\\u000a of copper stress, the germination percentage of wheat seeds decreased gradually. Pretreatment during wheat seed imbibition\\u000a with sodium nitroprusside (SNP), an NO donor, could

Kang-Di Hu; Lan-Ying Hu; Yan-Hong Li; Fen-Qin Zhang; Hua Zhang

2007-01-01

143

Toxicity of Cu, Pb, and Zn on Seed Germination and Young Seedlings of Wheat  

Microsoft Academic Search

\\u000a Seeds and young seedlings of wheat (Triticum aestivum\\u000a L.) under exposure to Copper (Cu), lead (Pb) and Zinc (Zn) were studied by employing a hydroponic experiment. Addition of Cu\\u000a or Pb or Zn to the solution inhibited seed germination, plumule and radicle elongation. The toxic of metals to seed germination\\u000a parameters can be arranged in the rank order of inhibition

Haiou Wang; Guangrong Zhong; Guoqing Shi; Fangting Pan

2010-01-01

144

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

145

Localization of prolamin in oat scutellum cells before and after seed germination.  

PubMed

Using fluorescent antibodies and high resolution light microscopy the reserve protein, prolamin (avenin) of oat scutellum was localized in the protein bodies of the scutellum cells of dry grain. But 1-3 days after seed germination, a large number of the protein bodies became devoid of prolamin indicating that the mobilization of prolamin in the scutellum of oat seeds after seed germination was very rapid. PMID:23194881

Zee, S Y; Chan, H Y; Ma, C Y

1984-08-01

146

Seed germination in response to chemicals: effect of nitrogen and pH in the media.  

PubMed

Seed germination generally presents a peak in the next growing season after a fire. Among other factors associated with fire are the increase of soil nitrogen and changes in the pH of the soil. In this study, we addressed the question, whether or not the germination response of eight species is linked with the increase in pH and nitrogenous compounds in the germination media? We assessed the separate and combined effects of nitrogenous compounds and pH on the percentage and rate of germination of seeds of Medicago arabica (L.) Hudson, Epilobium hirsutum L., Foeniculum vulgare Miller, Daucus carota L., Thapsia villosa L., Cynosurus cristatus L., Dactylis glomerata L. and Rumex crispus L. All these species are well represented in the Mediterranean ecosystems of the central-west Spain. Water and CaCl2 were used as controls. Nitrogenous compounds increased percent germination (level) and rate in three of the species studied. High pH negatively affected the germination rate of seeds from most species, but had no effect on the per cent germination of any of the species. The higher concentration of the nutritious solutions affected negatively the germination level and rate. The different germination responses of seeds of the studied species could not be exclusively attributed to pH values in the media, whereas the amount and form of Nitrogen in the media has a greater effect on it. These differences in germination are species dependent. PMID:16850869

Pérez-Fernández, M A; Calvo-Magro, E; Montanero-Fernández, J; Oyola-Velasco, J A

2006-01-01

147

?-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

148

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

149

Fructose 2,6-bisphosphate in germinating oat seeds. A biochemical study of seed dormancy.  

PubMed

When dormant oat seeds were imbibed at the non-permissive temperature of 30 degrees C, the concentration of phosphoenolpyruvate and of glycerate 3-phosphate, which are two inhibitors of phosphofructokinase 2, increased almost linearly during 30 h. By contrast, these metabolites increased only after a lag period of about 10 h in non-dormant seeds imbibed at the same temperature. As a consequence of this, the concentration of the C3 derivatives remained always remarkably lower in non-dormant than in dormant seeds. Accordingly, the concentration of fructose 2,6-bisphosphate, which increased similarly in the two types of seeds during the first 8 h after the start of inhibition, then reached a plateau in dormant seeds but continued to increase for another 8 h in non-dormant seeds, reaching a maximal value a few hours before the beginning of radicle protrusion. When the dormant seeds were imbibed at the permissive temperature of 10 degrees C, the evolution of all metabolites was slowed down but behaved like that of non-dormant seeds imbibed at 30 degrees C. Experiments in which the dormant seeds were submitted to a jump from 10 degrees C to 30 degrees C and vice versa, always provoked reverse changes in the concentration of the C3 derivatives and of fructose 2,6-bisphosphate, the latter being increased in all conditions that allowed germination. Dormant seeds were also allowed to germinate at 30 degrees C by imbibition during 24 h in the presence of 3% ethanol. Again, this permissive treatment caused an arrest in the accumulation of C3 derivatives and an increase in fructose 2,6-bisphosphate. Another, apparently unrelated, biochemical difference between dormant and non-dormant oat seeds was their inorganic pyrophosphate content, which was approximately five-fold higher in non-dormant than in dormant seeds. This difference was observed before and persisted during imbibition as long as measurement could be made and was not affected by the temperature jumps or by ethanol. In contrast to the phosphoric esters under investigation, pyrophosphate was not preferentially located in the embryo. PMID:2956097

Larondelle, Y; Corbineau, F; Dethier, M; Come, D; Hers, H G

1987-08-01

150

Effects of matriconditioning on onion seed germination, seedling emergence and associated physical and metabolic events  

Microsoft Academic Search

The effect of matriconditioning, the physiological presowing seed technique, using Micro-Cel E on Allium cepa L. cv. Czerniakowska seed quality was studied. Several ratios of seeds, carrier, water and time of priming were tested. The most effective treatment for improving onion seed germination at most tested temperatures was priming to a ratio of 2 g seed:1 g Micro-Cel:3 g water

Ewa K?pczy?ska; Justyna Pi?kna-Grochala; Jan K?pczy?ski

2003-01-01

151

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, Beatrice; Cueff, Gwendal; Rajjou, Loic

2013-01-01

152

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

153

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

154

Dynamics and partitioning of the ionome in seeds and germinating seedlings of winter oilseed rape.  

PubMed

Germination and seedling establishment are among the most critical phases in the development of plants, and seed vigour has become an important trait for the selection of robust crop cultivars. Little is known about the potentially limiting role of mineral nutrients in early metabolic and developmental processes during germination. Therefore, we assessed the ionome and relative distribution of mineral elements in different seed and seedling tissues of oilseed rape (Brassica napus L.) and monitored the internal allocation of nutrients during germination. In seeds, cotyledons harboured the main pool of K, P, S, Mg, Fe, Mn and Zn, whereas the seed coat contained most of the Ca, Na, B, Cu and Mo. Although the early root and hypocotyl tissue expanded first, concentrations of most elements were initially low. Re-allocation of elements to the root/hypocotyl tissue from other pools set in two days after seed imbibition and was most rapid for K. Relative to the critical deficiency levels of vegetative tissues, seed tissues were particularly low in B, K and Fe. Further analyses of the ionome of seeds and seedlings, grouped according to their germination efficiency, indicated that in particular low S, Mg and Ca coincided with germination failure. This study documents highly dynamic changes in the ionome of seed and seedling tissues and provides evidence for potentially limiting elements during early germination and seedling establishment in rapeseed. PMID:23939714

Eggert, Kai; von Wirén, Nicolaus

2013-09-01

155

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

156

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

157

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

158

4. The role of plant growth regulators in the germination of forest tree seeds  

Microsoft Academic Search

To establish a role for PGRs in the germination of forest tree seeds, it must be demonstrated that PGRs are involved in the mechanisms that control the induction of and release from dormancy, and also that these mechanisms are operative in the seeds of woody plants. Four currently known concepts of seed dormancy are reviewed, citing the published evidence relating

C. L. Leadem

1987-01-01

159

Effect of chemical and physical factors to improve the germination rate of Echinacea angustifolia seeds  

Microsoft Academic Search

Seeds of Echinacea angustifolia are known for their deep dormancy. In this paper, we studied the responses of E. angustifolia seeds to some chemical and physical factors, such as scarification, chilling (5°C) period, light and applied BA (6-benzylaminopurine), GA3 (gibberellic acid) and sound stimulation. When the seed coat layers were removed, the germination rate grew up from 6 to 20%

Duan Chuanren; Wang Bochu; Liu Wanqian; Chen Jing; Lian Jie; Zhao Huan

2004-01-01

160

Consumption of wheat seed reserves during germination and early growth as affected by soil water potential  

Microsoft Academic Search

Seed size and weight are important criteria for determining seedling vigour and stand establishment. Evolution of seed dry weight of wheat (Triticum aestivum L.) during germination and early growth was examined because poor stands are often associated with the depletion and exhaustion of seed reserves. Two laboratory experiments were conducted on filter paper and in soil at three water potentials

A. Bouaziz; D. R. Hicks

1990-01-01

161

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 three expansin genes that are expressed in tomato (Lycopersicon esculentum Mill.) seeds during of seeds of tomato (Lyco- persicon esculentum Mill.) and other Solanaceae (Sa´nchez et al., 1990; Dahal et

Bradford, Kent

162

Factors influencing seed germination of medicinal plant Salvia aegyptiaca L. (Lamiaceae)  

PubMed Central

Salvia aegyptiaca is a xerophytic perennial herb belongs to the Lamiaceae family commonly used for medicinal purposes. Laboratory experiments were carried out to assess the effects of temperature and salinity on seed germination and recovery responses after transferring to distilled water. Temperatures between 10 and 40 °C seem to be favourable for the germination of this species. Germination was inhibited by either an increase or decrease in temperature from the optimum (30 °C). The highest germination percentages were obtained at 0 mM NaCl; however, the increase of solution osmolalities progressively inhibited seed germination. The germination rate decreased with an increase in salinity for most of tested temperatures, but comparatively higher rates were obtained at 30 °C. Salt stress decreased both the percentage and the rate of germination. An interaction between salinity and temperature yielded no germination at 300 mM NaCl. By experimental transfer to distilled water, S. aegyptiaca seeds that were exposed to moderately saline conditions recovered and keep their ability to germinate mostly at low temperatures. At 300 mM NaCl, germination recovery decreased with increasing temperature and it was completely inhibited at 40 °C. PMID:23961132

Gorai, Mustapha; Gasmi, Hayet; Neffati, Mohamed

2011-01-01

163

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

164

Germination of Ocotea pulchella (Nees) Mez (Lauraceae) seeds in laboratory and natural restinga environment conditions.  

PubMed

The germination response of Ocotea pulchella (Nees) Mez seeds to light, temperature, water level and pulp presence is introduced. The laboratory assays were carried out in germination chambers and thermal-gradient apparatus, whereas the field assays were performed in environments with distinct light, temperature and soil moisture conditions within a permanent parcel of Restinga forest of the Parque Estadual da Ilha do Cardoso, Cananéia, São Paulo. The seeds do not exhibit dormancy, they are non photoblastic, and a loss of viability in dry stored seeds can be related to a decrease in water content of the seed. The presence of the pulp and the flooded substratum influenced negatively the germination of O. pulchella seeds tested in the laboratory. Otherwise, light and temperature probably are not limiting factors of the germination of O. pulchella seeds in the natural environment of Restinga. The optimum temperature range for germination of Ocotea pulchella seeds was 20 to 32 degrees C, the minimum or base temperature estimated was 11 degrees C and the maximum ranged between 33 and 42 degrees C. The isotherms exhibited a sigmoidal pattern well described by the Weibull model in the sub-optimal temperature range. The germinability of O. pulchella seeds in the understorey, both in wet and dry soil, was higher than in gaps. Germination was not affected by fluctuations in soil moisture content in the understorey environment, whereas in gaps, germination was higher in wet soils. Thus, the germination of this species involves the interaction of two or more factors and it cannot be explained by a single factor. PMID:19802455

Pires, L A; Cardoso, V J M; Joly, C A; Rodrigues, R R

2009-08-01

165

[Impact of priming on seed germination and seedling growth of Oldenlandia diffusa under drought stress].  

PubMed

Current study was carried out to optimize the priming condition of Oldenlandia diffusa seeds, and improve germination rate and seed vigor of 0. diffusa seeds under drought conditions. Uniform design was used to optimize the concentration and priming time of three priming materials (PEG, KNO3, GA3). Different concentrations of polyethylene glycol (PEG) was used to simulate drought stress. The seedling was cultured in 1/4 Hoagland medium for 30 d. The results showed that seed priming treatment with 366 mg x kg(-1) GA3 for 1h resulted in significant increase in germination rate, germination index, vigor, root length, plant height and biomass of O. diffusa seeds under drought stress (15% PEG), while seed priming with 3.0% KNO3 for 1 h showed little effect on germination and growth of O. diffusa seeds under drought stress. Seed priming treatment with appropriate GA3 concentration and priming time could enhance seed germination and drought resistance of O. diffusa in seedling stage. PMID:25039170

Zhu, Zai-Biao; Lu, Wei-Wei; Guo, Qiao-Sheng; Cao, Ya-Yue; Feng, Shan; Ning, Zi-Jun

2014-04-01

166

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

E-print Network

: Seeds of Scirpus litoralis and Scirpus maritimus were collected and force fed to mallards (Anas platyrhynchos). Both the ingested seeds (passage) and non-ingested seeds (controls) were exposed, in germination

Green, Andy J.

167

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

168

Optimization of chitosan treatments for managing microflora in lettuce seeds without affecting germination.  

PubMed

Many studies have focused on seed decontamination but no one has been capable of eliminating all pathogenic bacteria. Two objectives were followed. First, to assess the in vitro antimicrobial activity of chitosan against: (a) Escherichia coli O157:H7, (b) native microflora of lettuce and (c) native microflora of lettuce seeds. Second, to evaluate the efficiency of chitosan on reducing microflora on lettuce seeds. The overall goal was to find a combination of contact time and chitosan concentration that reduces the microflora of lettuce seeds, without affecting germination. After treatment lettuce seeds presented no detectable microbial counts (<10(2)CFU/50 seeds) for all populations. Moreover, chitosan eliminated E. coli. Regardless of the reduction in the microbial load, a 90% reduction on germination makes imbibition with chitosan, uneconomical. Subsequent treatments identified the optimal treatment as 10 min contact with a 10 g/L chitosan solution, which maintained the highest germination percentage. PMID:23218371

Goñi, M G; Moreira, M R; Viacava, G E; Roura, S I

2013-01-30

169

Seed germination during floatation and seedling growth of Carapa guianensis , a tree from flood-prone forests of the Amazon  

Microsoft Academic Search

Carapa guianensis Aubl. (Meliaceae), a hard wood tree from the Brazilian Amazon, has large recalcitrant seeds that can germinate and establish in both flood-free (terra-firme) and flood-prone (várzea) forests. These seeds, although large, can float. This study was designed to experimentally examine seed longevity under floating conditions ex-situ and its effects on subsequent germination and seedling growth. Many seeds germinated

Fábio R. Scarano; Tânia S. Pereira; Giselle Rôças

2003-01-01

170

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

171

Seed germination ecology of the summer annual Cyperus squarrosus in an unpredictable mudflat habitat  

Microsoft Academic Search

The purpose of our study was to better understand seed germination ecology of the summer annual sedge Cyperus squarrosus, which grows in various habitats, including mudflats and shallow soil over limestone bedrock (rock outcrops), where timing of the period favorable for germination and completion of the life cycle is unpredictable. Over a 28.5-month period, temperature and light:dark requirements for germination

Carol C Baskin; Jerry M Baskin; Edward W Chester

2004-01-01

172

Histochemical studies on protease formation in the cotyledons of germinating bean seeds  

Microsoft Academic Search

Protease formation in Phaseolus vulgaris L. cotyledons during seed germination was studied histochemically using a gelatin-film-substrate method. Protease activity can be detected by this method on the 5th day of germination, at approximately the same time that a rapid increase of activity was observed by a test-tube assay with casein as a substrate. At the early stage of germination, protease

Harugoro Yomo; Margery Poole Taylor

1973-01-01

173

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

174

Allelopathic effects of weeds extracts against seed germination of some plants.  

PubMed

This study investigated the allelopathic effects of various weeds extracts on seed germination of 11 crop species. Most of the weed extracts tested had inhibitory effects on seed germination of common bean, tomato, pepper, squash, onion, barley, wheat, and corn at different application rates as compared with the 10% acetone control. Chickpea seed germination was inhibited by extracts of Solanum nigrum L., Chenopodium album L., and Matricaria chamomilla L. (10%, 20% and 22.5%, respectively) at the end of 21 day incubation period. However, Glycyrrhiza glabra L., Sorghum halepense (L.) Pers., and Reseda lutea L. extracts stimulated chickpea seed germination at the rates of 95%, 94%, and 93%, respectively, compared to control. It was concluded that some of the weed extracts tested in this study could be used as inhibitor while others could be used as stimulator for the crops. PMID:16161968

Kadioglu, Izzet; Yanar, Yusuf; Asav, Unal

2005-04-01

175

[Effects of litter coverage and watering frequency on seed germination and seedling survival of Castanopsis fissa].  

PubMed

Castanopsis fissa is an important pioneer species commonly used in the restoration of degraded subtropical grassland in southern China. The study on the effects of litter coverage and watering frequency on the seed germination and seedling survival of C. fissa showed that the effects of litter coverage depended on soil moisture condition. When the watering frequency was 1 time per day, litter covering could restrain seed germination and increase seedling mortality; while watering 2 or 3 times per day, the covering would ameliorate soil moisture condition, and benefit seed germination and seedling establishment. The biomass of C. fissa seedlings was enhanced significantly by litter covering. It was suggested that keeping a litter layer on soil surface could benefit the seed germination and seedling survival of C. fissa to restore subtropical shrub land. PMID:19123340

Wang, Jun; Wang, Zhuo-Han; Yang, Long; Ren, Hai

2008-10-01

176

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

177

Influence of physico-chemical parameters of the aquatic medium on germination of Eichhornia crassipes seeds.  

PubMed

The germination of seeds of Eichhornia crassipes in locations distant from the foci of infestation may be a means of dispersal of this invasive plant. Nonetheless, no modern studies have examined the influence of single components on germination, although the influence of temperature, oxygen and redox potential was examined in earlier studies. The effects of pH, conductivity, nitrate, phosphate, potassium, calcium, iron and boron on germination of E. crassipes were determined in seed germination tests. The results showed that external input of nutrients influences germination, since neither pH nor conductivity alone had any effect, but there was a significant increase in germination in growth media containing phosphorus at 3.95 mg·l(-1) (P/L; 95.5%) and boron at 10 mg·l(-1) (B/L; 97.5%); at higher concentrations, the latter was toxic. These findings contribute to knowledge of factors controlling the germination of E. crassipes seeds. Consequently, E. crassipes seeds would find very good conditions for germination in water classified as hypereutrophic, which may play a decisive role in expansion of this plant. PMID:21668605

Albano Pérez, E; Ruiz Téllez, T; Sánchez Guzmán, J M

2011-07-01

178

Induction of vivipary in Arabidopsis by silique culture: implications for seed dormancy and germination  

Microsoft Academic Search

Culture of excised fruits (siliques) of different ages of Arabidopsis thaliana in a solidified mineral salt medium supplemented with vitamins, myo-inositol, and 3% sucrose induces vivipary. Whereas early stage and immature embryos complete their full development before germinating viviparously in seeds enclosed in the silique, mature green embryos enclosed in green ovules germinate without further growth in culture. Vivipary is

VAL RAGHAVAN

2002-01-01

179

Using Drip Irrigation to Germinate Seed and Set Transplants: Techniques and Benefits  

Microsoft Academic Search

In fruit and vegetable row crop production, many producers are successfully using drip irrigation systems to germinate seed and set transplants without the traditional use of sprinklers. This reduces runoff and decreases the water, labor, equipment and energy costs associated with sprinkler irrigation. Additional benefits of eliminating sprinkler irrigation include reduced weed germination, improved field accessibility, a reduced incidence of

Inge Bisconer

180

Stimulation and Promotion of Germination in Opuntia ficus-indica Seeds  

Microsoft Academic Search

Opuntia ficus-indica seeds, as many other Opuntia species, show low germination capacity due mainly to their hard lignified integuments, the most inward of these is the funiculus that envelops the embryo, obstructing radicle protrusion. The purpose of this study was to accelerate the initiation of the germination process and to shorten their completion time by the action of physical and

Mariela Altare; Sinibaldo Trione; Juan C. Guevara; Mariano Cony

181

Allelopathic effects of mesquite ( Prosopis juliflora ) foliage on seed germination and seedling growth of bermudagrass ( Cynodon dactylon )  

Microsoft Academic Search

Allelopathic effects of aqueous extracts of 10, 20, 30, 40, 50 and 60g dry mesquite (Prosopis juliflora) leaves in a litre of distilled water on seed germination and early growth of bermudagrass (Cynodon dactylon‘Common Bermuda’) at 30°C were investigated. The final germination percentage and the germination rate, as judged by corrected germination rate index (CGRI) and to a lesser extent

A. I. Al-Humaid; M. O. A. Warrag

1998-01-01

182

Effect of chemical and physical factors to improve the germination rate of Echinacea angustifolia seeds.  

PubMed

Seeds of Echinacea angustifolia are known for their deep dormancy. In this paper, we studied the responses of E. angustifolia seeds to some chemical and physical factors, such as scarification, chilling (5 degrees C) period, light and applied BA (6-benzylaminopurine), GA3 (gibberellic acid) and sound stimulation. When the seed coat layers were removed, the germination rate grew up from 6 to 20% (incubated in light) and the mean time germination (MTG) was reduced from 18 to 6.6 days. On the basis of layers-removed, chilling and continuous light gave significantly higher germination rate (up to 70%). Compare the data of seeds chilled by 0, 6, 12, 18 and 24 days, the maximum germination rate (up to 70%) achieved at 18-days chilling treatment. Further increases in the chilling period could slightly improve germination. Exogenous application of 0.1, 0.2, 0.3 mg/L GA3 or BA in the previous pretreatment increased germination to 78, 90 and 84% or 76, 86 and 84%, respectively. Obviously, the best concentration of GA or BA is 0.3 mg/L. And the GA3 or BA treatment shortened the MTG to about 4 days. The influence of sound stimulation was also tested in the experiment. The result showed that one 100 dB and 1000 Hz sound wave (sine-wave) was beneficial to the germination of E. angustifolia seeds. PMID:15342019

Chuanren, Duan; Bochu, Wang; Wanqian, Liu; Jing, Chen; Jie, Lian; Huan, Zhao

2004-09-01

183

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

184

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

185

Effects of arsenic on seed germination and physiological activities of wheat seedlings  

Microsoft Academic Search

The effects of arsenic (As) were investigated on seed germination, root and shoot length and their biomass and some other factors to elucidate the toxicity of As. The results showed low concentrations of As (0–1 mg\\/kg) stimulated seed germination and the growth of root and shoot, however, these factors all decreased gradually at high concentrations of As (5–20 mg\\/kg). The

Chun-xi LI; Shu-li FENG; Yun SHAO; Li-na JIANG; Xu-yang LU; Xiao-li HOU

2007-01-01

186

Effects of gamma rays irradiation on seed germination and growth of hard wheat  

Microsoft Academic Search

The effects of irradiation with low doses (0, 10, 20 and 30 Gy) of radioactive cobalt (60Co) ? rays on seed germination, shoot and epicotyl growth of hard wheat (Triticum durum Desf.) were investigated under laboratory and glasshouse conditions. Irradiated wheat seeds kept their germination speed\\u000a and capacity levels compared to the control. However, improvements of +18 and +32% were, respectively

Mongi Melki; A. Marouani

2010-01-01

187

Alteration of starch- sucrose transition in germinating wheat seed under sodium chloride salinity  

Microsoft Academic Search

Alterations in starch-sucrose transition during germination were studied in wheat seeds under saline conditions. NaCI significantly\\u000a reduced the speed of germination and resultant seedling growth, but delayed the degradation of seed storage components. The\\u000a endogenous level of ABA increased while osmotic potential decreased. NaCI also inhibited the expression of ?-amylase. Increasing\\u000a the concentration of NaCI induced the expression of sucrose

Mohammad Abul Kashem; Nilufa Sultana; Takeshi Ikeda; Hidetaka Hori; Tadeusz Loboda; Toshiaki Mitsui

2000-01-01

188

Effects of low-level microwave radiation on germination and growth rate in corn seeds  

Microsoft Academic Search

Experiments were conducted to investigate the effects of microwave radiation on germination and growth rate in corn seeds. Specimens were irradiated in an anechoic chamber, for 22 to 24 h, at CW power density levels from 10 mW\\/cm2to 30 mW\\/cm2. The radiation frequency was 9 GHz. Marked inhibition of seed germination was observed in radiated specimens, probably as a result

J. Bigu-Del-Blanco; J. M. Bristow; C. Romero-Sierra

1977-01-01

189

Effect of the embryo axis on catalase in the endosperm of germinating castor bean seeds  

Microsoft Academic Search

The effect of the embryo axis on the activity of the glyoxysomal enzyme catalase (EC 1.11.1.6) in the endosperm of germinating castor bean (Ricinus communis L. cv. Hale) seeds was examined. The presence of the embryo axis was required for maximum levels of catalase enzyme activity and protein levels in cell-free extracts of endosperms from germinated seeds. In contrast, RNA

Robert T Mullen; David J Gifford

1995-01-01

190

Mode of phytochrome B action in the photoregulation of seed germination in Arabidopsis thaliana  

Microsoft Academic Search

Summary Arabidopsis thaliana seeds imbibed for a short duration show phytochrome B (PhyB)-specific photo-induction of germination. Using this system, the relationship was determined between the amount of PhyB in seeds and photon energy required for PhyB-specific germination in two transgenic Arabidopsis lines transformed with either the Arabidopsis PhyB cDNA (ABO) or the rice PhyB cDNA (RBO). Immunochemical detection of PhyB

Tomoko Shinomura; Hiroko Hanzawa; Eberhard Schafer; Masaki Furuya

1998-01-01

191

Germination and Early Seedling Growth of Chaffy-Seeded Grasses at Negative Water Potentials  

Microsoft Academic Search

chaffy-seeded grasses can be debearded, i.e., removal ofthehairsandawn(Ahringet al.,1964)orprocessedto Drought is the most frequent cause of stand establishment failure remove all appendages leaving only caryopses (Beisel, of native grasses. An experiment was conducted to determine the interactions of seed processing and simulated dry conditions on seed 1985). When conditions are favorable, planting caryop- germination and seedling growth of five chaffy-seeded,

T. L. Springer

2005-01-01

192

Varietal variation and physiological basis for inhibition of wheat seed germination after excessive water treatment  

Microsoft Academic Search

Soaking the seeds of most upland plants in water before sowing results in poor germination. Varietal differences in flooding\\u000a tolerance of seeds have been reported in maize, soybean, barley and so on. This study was conducted to evaluate the varietal\\u000a difference in wheat (2n = 42) seeds to soaking injury and to examine the importance of ethanol accumulation and seed

Kihachi Ueno; Hidekazu Takahashi

1997-01-01

193

Quantitative Models Characterizing Seed Germination Responses to Abscisic Acid and Osmoticum 1  

PubMed Central

Mathematical models were developed to characterize the physiological bases of the responses of tomato (Lycopersicon esculentum Mill. cv T5) seed germination to water potential (?) and abscisic acid (ABA). Using probit analysis, three parameters were derived that can describe the germination time courses of a seed population at different ? or ABA levels. For the response of seed germination to reduced ?, these parameters are the mean base water potential (¯?b, MPa), the standard deviation of the base water potential among seeds in the population (??b, MPa), and the “hydrotime constant” (?H, MPa·h). For the response to ABA, they are the log of the mean base ABA concentration ([unk]ABAb, m), the standard deviation of the base ABA concentration among seeds in the population (?ABAb, log[m]), and the “ABA-time constant” (?ABA, log[m]·h). The values of ¯?b and [unk]ABAb provide quantitative estimates of the mean sensitivity of germination rate to ? or ABA, whereas ??b and ?ABAb account for the variation in sensitivity among seeds in the population. The time constants, ?H and ?ABA, indicate the extent to which germination rate will be affected by a given change in ? or ABA. Using only these parameters, germination time courses can be predicted with reasonable accuracy at any medium ? according to the equation probit(g) = [? - (?H/tg) - ¯?b]/??b, or at any ABA concentration according to the equation probit(g) = [log[ABA] - (?ABA/tg) - log[[unk]ABAb

Ni, Bing-Rui; Bradford, Kent J.

1992-01-01

194

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

195

Ascorbic acid and reactive oxygen species are involved in the inhibition of seed germination by abscisic acid in rice seeds.  

PubMed

The antagonism between abscisic acid (ABA) and gibberellin (GA) plays a key role in controlling seed germination, but the mechanism of antagonism during this process is not known. The possible links among ABA, reactive oxygen species (ROS), ascorbic acid (ASC), and GA during rice seed germination were investigated. Unlike in non-seed tissues where ROS production is increased by ABA, ABA reduced ROS production in imbibed rice seeds, especially in the embryo region. Such reduced ROS also led to an inhibition of ASC production. GA accumulation was also suppressed by a reduced ROS and ASC level, which was indicated by the inhibited expression of GA biosynthesis genes, amylase genes, and enzyme activity. Application of exogenous ASC can partially rescue seed germination from ABA treatment. Production of ASC, which acts as a substrate in GA biosynthesis, was significantly inhibited by lycorine which thus suppressed the accumulation of GA. Consequently, expression of GA biosynthesis genes was suppressed by the low levels of ROS and ASC in ABA-treated seeds. It can be concluded that ABA regulates seed germination in multiple dimensions. ROS and ASC are involved in its inhibition of GA biosynthesis. PMID:22200664

Ye, Nenghui; Zhu, Guohui; Liu, Yinggao; Zhang, Aying; Li, Yingxuan; Liu, Rui; Shi, Lu; Jia, Liguo; Zhang, Jianhua

2012-03-01

196

Identification of a Soybean MOTHER OF FT AND TFL1 Homolog Involved in Regulation of Seed Germination  

PubMed Central

Seed germination is an important event in the life cycle of seed plants, and is controlled by complex and coordinated genetic networks. Many genes involved in the regulation of this process have been identified in different plant species so far. Recent studies in both Arabidopsis and wheat have uncovered a new role of MOTHER OF FT AND TFL1 (MFT) in seed germination. Here, we reported a homolog of MFT in soybean (GmMFT) which strongly expressed in seeds. Detailed expression analysis showed that the mRNA level of GmMFT increased with seed development but declined during seed germination. The transcription of GmMFT also responded to exogenous application of ABA and GA3. Ectopic expression of GmMFT CDS in Arabidopsis moderately inhibited seed germination. All these evidences suggest that GmMFT may be a negative regulator of seed germination. PMID:24932489

Wang, Xu; Wu, Faqiang; Hu, Ruibo; Fu, Yongfu

2014-01-01

197

Identification of a soybean MOTHER OF FT AND TFL1 homolog involved in regulation of seed germination.  

PubMed

Seed germination is an important event in the life cycle of seed plants, and is controlled by complex and coordinated genetic networks. Many genes involved in the regulation of this process have been identified in different plant species so far. Recent studies in both Arabidopsis and wheat have uncovered a new role of MOTHER OF FT AND TFL1 (MFT) in seed germination. Here, we reported a homolog of MFT in soybean (GmMFT) which strongly expressed in seeds. Detailed expression analysis showed that the mRNA level of GmMFT increased with seed development but declined during seed germination. The transcription of GmMFT also responded to exogenous application of ABA and GA3. Ectopic expression of GmMFT CDS in Arabidopsis moderately inhibited seed germination. All these evidences suggest that GmMFT may be a negative regulator of seed germination. PMID:24932489

Li, Qing; Fan, Chengming; Zhang, Xiaomei; Wang, Xu; Wu, Faqiang; Hu, Ruibo; Fu, Yongfu

2014-01-01

198

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

199

Molecular and physiological dissection of enhanced seed germination using short-term low-concentration salt seed priming in tomato.  

PubMed

Seed germination is the initial step of plant development. Seed priming with salt promotes seed germination in tomato (Solanum lycopersicum L.); however, the molecular and physiological mechanisms underlying the enhancement of seed germination by priming remain to be elucidated. In this study, we examined the following in seeds both during and after priming treatment: the endogenous abscisic acid (ABA) and gibberellin (GA) concentrations; the expression of genes encoding ABA catabolic and GA biosynthesis enzymes, including 8'-hydroxylase (CYP707A), copalyl diphosphate synthase (CPS), GA 20-oxidase (GA20ox) and GA 3-oxidase (GA3ox); and endosperm cap weakening enzymes, including expansin (EXP), class I ?-1,3-glucanase (GulB), endo-?-mannanase (MAN) and xyloglucan endotransglucosylase (XTH). Tomato seeds were soaked for 24 h at 25 °C in the dark in 300 mM NaCl (NaCl-priming) or distilled water (hydro-priming). For both priming treatments, the ABA content in the seeds increased during treatment but rapidly decreased after sowing. Both during and after the priming treatments, the ABA levels in the hydro-primed seeds and NaCl-primed seeds were not significantly different. The expression levels of SlGA20ox1, SlGA3ox1 and SlGA3ox2 were significantly enhanced in the NaCl-primed seeds compared to the hydro-primed seeds. The GA(4) content was quantifiable after both types of priming, indicating that GA(4) is the major bioactive GA molecule involved in tomato seed germination. The GA(4) content was significantly higher in the NaCl-primed seeds than in the hydro-primed seeds 12 h after sowing and thereafter. Additionally, the peak expression levels of SlEXP4, SlGulB, SlMAN2 and SlXTH4 occurred earlier and were significantly higher in the NaCl-primed seeds than in the hydro-primed seeds. These results suggest that the observed effect of NaCl-priming on tomato seed germination is caused by an increase of the GA(4) content via GA biosynthetic gene activation and a subsequent increase in the expression of genes related to endosperm cap weakening. PMID:22305065

Nakaune, Makoto; Hanada, Atsushi; Yin, Yong-Gen; Matsukura, Chiaki; Yamaguchi, Shinjiro; Ezura, Hiroshi

2012-03-01

200

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

201

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

E-print Network

Thermoinhibition Introduction Plant seeds and fruits have evolved as the typical propa- gation and dispersal units of a species in a particular ecosystem. Adaptation of germination to abiotic stresses and changing summarize the current knowledge about their role in seeds. While it seems very clear that jasmonates inhibit

Leubner, Gerhard

202

Effects of sand burial depth on seed germination and seedling emergence of Cirsium pitcheri  

Microsoft Academic Search

A greenhouse study was conducted to determine the effects of sand burial on seed germination and seedling emergence of Cirsium pitcheri, a threatened species along Lake Huron sand dunes. In October 1996, seeds of C. pitcheri were sorted into three groups (small, medium and large) and artificially buried at 2, 4, 6, 8, 10 and 12 cm depths in plastic

Hua Chen; M. A. Maun

1999-01-01

203

A genetic locus and gene expression patterns associated with the priming effect on lettuce seed germination at elevated temperatures  

Microsoft Academic Search

Seeds of most cultivated varieties of lettuce (Lactuca sativa L.) fail to germinate at warm temperatures (i.e., above 25–30°C). Seed priming (controlled hydration followed by drying)\\u000a alleviates this thermoinhibition by increasing the maximum germination temperature. We conducted a quantitative trait locus\\u000a (QTL) analysis of seed germination responses to priming using a recombinant inbred line (RIL) population derived from a cross

Andrés R. Schwember; Kent J. Bradford

2010-01-01

204

Lead-induced phytotoxicity mechanism involved in seed germination and seedling growth of wheat ( Triticum aestivum L.)  

Microsoft Academic Search

The mechanism of lead-inhibitory effects on seed germination and seedling growth was investigated in wheat cv. Xihan 2 subjected to different Pb(NO3)2 concentrations. High concentrations of lead and exogenous H2O2 significantly inhibited seed germination and the growth of roots and shoots. Dimethylthiourea, catalase or diphenylene iodonium could reverse lead-inhibitory effects on seed germination. Significant elevated H2O2 generation was observed in

Yingli Yang; Xueling Wei; Jin Lu; Jia You; Wenrui Wang; Ruxia Shi

2010-01-01

205

Seed dispersal and germination patternsin a rare Mediterranean island endemic ( Anchusa crispa Viv., Boraginaceae)  

NASA Astrophysics Data System (ADS)

We analyse and discuss patterns of seed dispersal and germination of a rare endemic plant species, Anchusa crispa Viv. (Boraginaceae) from Corsica and Sardinia. This coastal plant inhabits dunes and back-dunes, and currently numbers only a few thousand individuals which generally occur in isolated populations. This study included experiments conducted in the field in Corsica and also under controlled conditions in the laboratory. Short-distance dispersal of A. crispa is performed by ants, both by myrmecochory and dyszoochory. The invasion of an exotic species of ant, Linepithema humile, could locally modify the dispersal system and possibly the population dynamics of A. crispa. Long-distance dispersal may occur by water transport since seeds can germinate after at least 1 week of immersion in seawater and readily float on the surface. Burial of seeds is favourable for germination, percentage germination being maximised at a depth of 1-2 cm below the soil surface. A. crispa has a seed bank of about ten viable seeds per m 2, which may contribute to the survival of this species which exists in small populations with a short life span. Due to its seed dispersal and germination patterns, the conservation of this species will necessitate that human disturbance, which can destabilise the surface of the sand is prevented and that new populations are introduced to favourable sites.

Quilichini, Angélique; Debussche, Max

2000-12-01

206

[Research progress in seegrass seed dormancy, germination, and seedling growth and related affecting factors].  

PubMed

Seagrass bed is the main primary producer in coastal areas, having highly ecological and economical values, and being one of the most important shallow-marine ecosystems. This paper reviewed the research progress in the seed dormancy, germination, and seedling growth of seagrass and related affecting factors, summarized the seed dormancy modes and durations and their affecting factors, and discussed the effects of water salinity, temperature, transparency, hormone, dissolved oxygen, and population structure on the seed germination and the seedling survival and growth. Some issues in related researches and several research directions in the future were prospected. PMID:22303688

Zhang, Pei-Dong; Sun, Yan; Niu, Shu-Na; Zhang, Xiu-Mei

2011-11-01

207

Laboratory germination of seeds from 10 British species of Potamogeton  

Microsoft Academic Search

Factorial laboratory germination experiments were carried out on fruits from 10 British species of Potamogeton (Potamogetonaceae). Fruits had all been placed in a dry-room maintained at 15% RH and 15°C for 3–6 months from the time of collection.Maximum levels of germination ranged from 13% (P. polygonifolius) to 90% (P. berchtoldii). Whilst for some species, there was some germination across all

Fiona Hay; Robin Probert; Michelle Dawson

2008-01-01

208

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

209

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

210

ESTs analysis reveals putative genes involved in symbiotic seed germination in Dendrobium officinale.  

PubMed

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

211

Tropical rodents change rapidly germinating seeds into long-term food supplies  

Microsoft Academic Search

Seed-hoarding vertebrates may survive yearly periods of food scarcity by storing seeds during the preceding fruiting season. It is poorly understood why rodents creating long-term reserves, especially those in the tropics, incorporate seeds from plant species that germinate rapidly and hence seem unsuitable for long-term storage. We carried out a series of experiments to understand why red acouchies (Myoprocta exilis)

Patrick A. Jansen; F. J. J. M. Bongers; Herbert H. T. Prins

2006-01-01

212

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

PubMed

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 under alternating temperatures. However, dormant seeds will also germinate without a pre-treatment, albeit at a much slower rate, which gives rise to longer periods of imbibition before germination. Transcriptome analyses on seeds exposed to prolonged imbibition highlighted pathways associated with phenylpropanoid biosynthesis and interacting networks of genes involved in plant defense. In addition to the many pathways associated with phenylpropanoid biosynthesis enriched with down-regulated genes upon germination, there were also numerous pathways enriched with up-regulated genes associated with energy metabolism, such as glycolysis. Transcriptome data further suggest that metabolism and signaling by the plant hormones ethylene, gibberellin, and abscisic acid are involved in the developmental transition from dormancy to germination. More specifically, sub-network enrichment analysis identified ABI3 as a central hub of a sub-network at germination including several down-regulated genes such as DELLA (i.e., RGL2), which represses gibberellin signaling processes required for germination. The 595-fold increase in the expression of ACC oxidase (ACO4) at germination also suggests an important role for ethylene biosynthesis in germinating leafy surge seeds. Furthermore, the 10-578-fold difference in expression of many genes such as HY5 and Histone H3 between two populations at germination, which were treated with and without a constant temperature germination-enhancing pretreatment, revealed disparate impacts on various biosynthetic, growth, signaling, and response processes. Overall, our results indicate a constant temperature pretreatment (20°C for 21d) is not required for germination of leafy spurge seeds at an alternating temperature. However, the presence or absence of the pretreatment does affect the rate of germination and the germination transcriptional programs. PMID:23261266

Foley, Michael E; Chao, Wun S; Horvath, David P; Do?ramaci, Münevver; Anderson, James V

2013-04-15

213

Reversal by pressure of seed germination promoted by anesthetics  

Microsoft Academic Search

Germination of Panicum capillare L. caryopses induced by solutions of ethanol and ethyl ether was prevented by application of pressure >1 MPa during the period of exposure to the anesthetic. This effect of pressure indicates that germination is correlated with expansion at a site of anesthetic action in a cell membrane. The effects of several other anesthetics were measured on

S. B. Hendricks; R. B. Taylorson

1980-01-01

214

Arabidopsis WRKY2 transcription factor mediates seed germination and postgermination arrest of development by abscisic acid  

PubMed Central

Background Plant WRKY DNA-binding transcription factors are key regulators in certain developmental programs. A number of studies have suggested that WRKY genes may mediate seed germination and postgermination growth. However, it is unclear whether WRKY genes mediate ABA-dependent seed germination and postgermination growth arrest. Results To determine directly the role of Arabidopsis WRKY2 transcription factor during ABA-dependent seed germination and postgermination growth arrest, we isolated T-DNA insertion mutants. Two independent T-DNA insertion mutants for WRKY2 were hypersensitive to ABA responses only during seed germination and postgermination early growth. wrky2 mutants displayed delayed or decreased expression of ABI5 and ABI3, but increased or prolonged expression of Em1 and Em6. wrky2 mutants and wild type showed similar levels of expression for miR159 and its target genes MYB33 and MYB101. Analysis of WRKY2 expression level in ABA-insensitive and ABA-deficient mutants abi5-1, abi3-1, aba2-3 and aba3-1 further indicated that ABA-induced WRKY2 accumulation during germination and postgermination early growth requires ABI5, ABI3, ABA2 and ABA3. Conclusion ABA hypersensitivity of the wrky2 mutants during seed germination and postgermination early seedling establishment is attributable to elevated mRNA levels of ABI5, ABI3 and ABI5-induced Em1 and Em6 in the mutants. WRKY2-mediated ABA responses are independent of miR159 and its target genes MYB33 and MYB101. ABI5, ABI3, ABA2 and ABA3 are important regulators of the transcripts of WRKY2 by ABA treatment. Our results suggest that WRKY2 transcription factor mediates seed germination and postgermination developmental arrest by ABA. PMID:19622176

Jiang, Wenbo; Yu, Diqiu

2009-01-01

215

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

216

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

217

Priming of seeds with nitric oxide donor sodium nitroprusside (SNP) alleviates the inhibition on wheat seed germination by salt stress.  

PubMed

The effect of SNP, an NO donor, on seed germination of wheat (Triticum aestivum L. cv. 'DK961') under salt stress was studied. The results showed that priming of seeds with 0.06 mmol/L SNP for 24 h markedly alleviated the decrease of the germination percentage, germination index, vigor index and imbibition rate of wheat seeds under salt stress. SNP significantly alleviated the decrease of the beta-amylase activity but almost did not affect the alpha-amylase activity of wheat seeds under salt stress. SNP slightly increased the alpha-amylase isoenzymes (especially isoenzyme 3) and significantly increased the beta-amylase isoenzymes (especially isoenzyme d, e, f and g). SNP pretreatment decreased Na(+) content, but increased the K(+) content, resulting in a mark increase of K(+)/Na(+) ratio of wheat seedlings under salt stress. These results suggested that NO is involved in promoting wheat seed germination under salt stress by increasing the beta-amylase activity. PMID:17556812

Duan, Pei; Ding, Feng; Wang, Fang; Wang, Bao-Shan

2007-06-01

218

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

219

Removal of a combination of endocrine disruptors from aqueous systems by seedlings of radish and ryegrass.  

PubMed

Endocrine disruptors (EDs) are widespread in the environment, especially aquatic systems, and cause dangerous effects on wildlife and humans. This work was aimed to assess the capacity of radish (Raphanus sativus L.) and ryegrass (Lolium perenne L.) seedlings to tolerate and remove two combinations of EDs containing bisphenol A (BPA), 17alpha-ethynilestradiol (EE2), and linuron from four aqueous media: distilled water, a solution of natural organic matter (NOM), a lake water and a river water. Seeds of the two species were germinated in each contaminated medium and, at the end of germination, the seedling growth was evaluated by biometric measurements and residual EDs were quantified by chromatographic analysis. Biometric measurements revealed that the phytotoxicity of the two combinations of EDs depended on the medium used. Radish showed a discrete tolerance in distilled water and lake water but was inhibited in the solution of NOM and river water. Ryegrass was negatively affected mainly in river water. The concentration of each ED appeared significantly reduced in all media in the presence of seedlings of both species, but not in the blanks without plants. In 5 days, radish removed up to 88% of BPA, 100% of EE2 and 42% of linuron, and in 6 days ryegrass removed up to 92% of BPA, 74% of EE2 and 16% of linuron. The considerable removal capacity of radish and ryegrass in all media tested encourages the use of phytoremediation to remove EDs from waters. PMID:24617071

Gattullo, C Eliana; Cunha, Bruno Barboza; Rosa, André H; Loffredo, Elisabetta

2013-01-01

220

Dynamics of the antioxidant system during seed osmopriming, post-priming germination, and seedling establishment in Spinach (Spinacia oleracea).  

PubMed

Osmopriming is a pre-sowing treatment that improves seed germination performance and stress tolerance. To understand osmopriming physiology, and its association with post-priming stress tolerance, we investigated the antioxidant system dynamics during three stages: during osmopriming, post-priming germination, and seedling establishment. Spinach seeds (Spinacia oleracea L. cv. Bloomsdale) were primed with -0.6 MPa PEG at 15°C for 8 d, and dried at room temperature for 2 d. Unprimed and primed germinating seeds/seedlings were subjected to a chilling and desiccation stresses. Seed/seedling samples were collected for antioxidant assays and germination performance and stress tolerance were evaluated. Our data indicate that: (1) during osmopriming the transition of seeds from dry to germinating state represses the antioxidant pathways (residing in dry seeds) that involve CAT and SOD enzymes but stimulates another pathway (only detectable in imbibed seeds) involving APX; (2) a renewal of antioxidant system, possibly required by seedling establishment, occurs after roughly 5 d of germination; (3) osmopriming strengthens the antioxidant system and increases seed germination potential, resulting in an increased stress tolerance in germinating seeds. Osmopriming-mediated promotive effect on stress tolerance, however, may diminish in relatively older (e.g. ~5-week) seedlings. PMID:21421363

Chen, Keting; Arora, Rajeev

2011-02-01

221

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

222

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

223

Factors affecting germinable seed yield in Cypripedium calceolus var. pubescens (Willd.) Correll and Epipactis helleborine (L.) Crantz (Orchidaceae)  

Microsoft Academic Search

One of the challenges facing orchid conservationists is to get a better understanding of seed parent fecundity. This can be especially laborious for orchids whose seed is difficult to germinate. Mature seeds ofCypripedium calceolusvar.pubescens(Willd.) Correll (Orchidaceae) have been reported to require 8 weeks pre-chilling at 4°C and a further month at 20°C to induce germination, but seeds prematurely harvested at

M H. S LIGHT; M MacCONAILL

1998-01-01

224

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

225

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

226

Polyethylene glycol 6000 priming effect on germination of aged wheat seed lots  

Microsoft Academic Search

The effects of PEG 6000 priming on germination performance of aged wheat seed lots have been studied. A correct application\\u000a of osmopriming treatment indicated a relationship between the pattern of water absorption, the reactivation of mitotic activity\\u000a and the start and synchronization of germination. The possibility of controlling pregerminative events by means of this treatment\\u000a is discussed on the physiological

A. Dell’Aquila; D. Pignone; G. Carella

1984-01-01

227

Lead phytotoxicity on wheat ( Triticum aestivum L.) seed germination and seedlings growth  

Microsoft Academic Search

Lead (Pb) is an environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, experiments focusing on germination of wheat seeds were germinated in a solution containing Pb (NO3)2 (0.05; 0.1; 0.5; 1g\\/L) during 6 days. Lead accumulation in seedlings was positively correlated with the external concentrations, and negatively correlated with morphological parameters of plant

Mostafa Lamhamdi; Ahmed Bakrim; Ahmed Aarab; René Lafont; Fouad Sayah

2011-01-01

228

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

229

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

230

The effects of methyl jasmonate on sunflower (Helianthus annuus L.) seed germination and seedling development  

Microsoft Academic Search

Some effects of methyl jasmonate (Me-Ja) on sunflower (Helianthus annuus L.) seed germination and seedling development are described and compared with those of ABA. Both growth regulators have very similar action. They inhibit germination, but high concentrations of O2 in the atmosphere suppress this inhibitory action. Depending on the concentration, Me-Ja inhibits root and hypcotyl growth, however the root is

F. Corbineau; R. M. Rudnicki; D. Côme

1988-01-01

231

Pre-germination genotypic screening using PCR amplification of half-seeds.  

PubMed

A simple and rapid PCR-based method has been developed for determining the genotype of seeds before germination. Single half-seeds of rice (Oryza sativa L.) and wheat (Triticum aestivum L. em. Thell.) were preincubated, without grinding, in an aqueous extraction buffer. The resulting supernatants were then used in polymerase chain reaction (PCR) with oligonucleotide primers corresponding to rice single-copy sequences or a wheat microsatellite repeat. PCR products of identical size were amplified using either the half-seed extract or DNA isolated from leaf tissue. The remnant half-seeds can be maintained in ordered arrays using microtiter plates allowing the recovery of selected genotypes. Pre-germination genotypic screening of seed populations as described in this report should be useful for a variety of applications in plant breeding and genetics studies. PMID:24193778

Chunwongse, J; Martin, G B; Tanksley, S D

1993-07-01

232

[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

233

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

234

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

235

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

236

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

237

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, Rene

1984-01-01

238

Indole-3-acetic acid biosynthesis in isolated axes from germinating bean seeds: The effect of wounding on the biosynthetic pathway  

E-print Network

Indole-3-acetic acid biosynthesis in isolated axes from germinating bean seeds: The effect pathways were analyzed in isolated axes of germinating bean seedlings at various times after cotyledon are primarily responsible for the IAA biosynthesis occurring in isolated axes of germinating bean seedlings

Cooke, Todd J.

239

Changes in germination, growth and soluble sugar contents of Sorghum bicolor (L.) Moench seeds under various abiotic stresses  

Microsoft Academic Search

The effect of various abiotic stresses on germination rate, growth and soluble sugar content in Sorghum bicolor (L.) Moench cv. CSH 6 seed embryos and endosperm during early germination was investigated. Under stress conditions germination, water potential and tissue water content decreased markedly. Subsequently, this reduction resulted in marked decreases in fresh weight both in embryos and endosperm. Conversely, a

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

2003-01-01

240

Effect of bacterial population density on germination wheat seeds and dynamics of simple artificial ecosystems  

NASA Astrophysics Data System (ADS)

Effect of the size of rhizospheric bacterial populations on germination of seeds and development of simple terrestrial "wheat plants - rhizospheric microorganisms - artificial soil" and "wheat plants - artificial soil" systems has been studied. Experiments demonstrated that within specify ranges in the inoculate, the rhizospheric bacteria are capable of increasing the yield of germinated seeds and stimulate the growth of plantlets. Germination of seeds inoculated with bacteria was either stimulated, or inhibited or remained at control levels depending on the amount of bacteria. Plant biomass growth and total photoassimilation has been found to depend on the amount of bacteria on the plant roots: the higher the amount of bacteria on plant roots, the smaller is the biomass of plants but the total photoassimilation is, higher. Thus, depending on the amount of bacteria on the roots of plants the system either increases the biomass of plants or increases the total photoassimilation, i.e. "pumps" carbon through itself involving bacteria.

Somova, L. A.; Pechurkin, N. S.; Sarangova, A. B.; Pisman, T. I.

241

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

242

Copper affects the cotyledonary carbohydrate status during the germination of bean seed.  

PubMed

Seeds of bean (Phaseolus vulgaris L.) were germinated by soaking in distilled water or copper chloride solution. The relationships among copper excess treatment, germination rate, dry weight, sugar contents, and carbohydrase activities in cotyledon were investigated. Heavy metal stress provoked a diminution in germination rate and biomass mobilization, as compared with the control. A drastic disorder in soluble sugars export, especially glucose and fructose liberation, was also imposed after exposure to excess copper. This restricted the starch and sucrose breakdown in reserve tissue, as evidenced by the inhibition in the activities of alpha-amylase and invertase isoenzymes (soluble acid, soluble neutral, cell wall-bound acid). PMID:19888556

Sfaxi-Bousbih, Amira; Chaoui, Abdelilah; El Ferjani, Ezzedine

2010-10-01

243

Hormonal and molecular events during seed dormancy release and germination  

E-print Network

no effect on the kinetics of testa rupture, but it inhibits the post-germinational extension growth and Schopfer, 1983). Detipping can also replace the requirement for treatment with gibberellin (GA), a positive

Leubner, Gerhard

244

TaMFT-A1 Is Associated with Seed Germination Sensitive to Temperature in Winter Wheat  

PubMed Central

The ability of seed to germinate under favorable environmental conditions is critical for seedling emergence, plant establishment, subsequent development and growth of adult plants, and it is controlled by internal genetic factors and external environmental factors. Winter wheat in the southern Great Plains is often planted six weeks before the optimal planting date to produce more biomass for cattle grazing during the winter season. A high seed germination rate in this higher soil temperature environment is required for this specific management system. In this study, a major QTL for temperature-sensitive germination was mapped on the short arm of chromosome 3A (QTsg.osu-3A) in a RIL population generated from two winter wheat cultivars. Furthermore, TaMFT-A1, previously reported to regulate seed dormancy and pre-harvest sprouting in spring wheat cultivars, was mapped tightly associated with the peak of QTsg.osu-3A. However, allelic variation in TaMFT-A1 between the two winter wheat cultivars differed from that was observed in spring wheat cultivars. There were 87 SNPs (single nucleotide polymorphisms) and 12 indels (insertions/deletions) in TaMFT-A1 between the Jagger allele for high germination and the 2174 allele for low germination in the after-ripened seeds, in comparison with 2 SNPs between the two alleles for differential pre-harvest sprouting in spring wheat cultivars. The Jagger TaMFT-A1 allele is a novel haplotype and appears extensively in winter wheat cultivars. TaMFT-A1 transcript levels were up-regulated by high temperature but down-regulated by low temperature or seed storage time. These findings suggest that TaMFT-A1 may invoke different mechanisms for controlling seed dormancy/germination among winter wheat cultivars. PMID:24069187

Wang, Shuwen; Zhu, Meirong; Carver, Brett F.; Yan, Liuling

2013-01-01

245

TaMFT-A1 is associated with seed germination sensitive to temperature in winter wheat.  

PubMed

The ability of seed to germinate under favorable environmental conditions is critical for seedling emergence, plant establishment, subsequent development and growth of adult plants, and it is controlled by internal genetic factors and external environmental factors. Winter wheat in the southern Great Plains is often planted six weeks before the optimal planting date to produce more biomass for cattle grazing during the winter season. A high seed germination rate in this higher soil temperature environment is required for this specific management system. In this study, a major QTL for temperature-sensitive germination was mapped on the short arm of chromosome 3A (QTsg.osu-3A) in a RIL population generated from two winter wheat cultivars. Furthermore, TaMFT-A1, previously reported to regulate seed dormancy and pre-harvest sprouting in spring wheat cultivars, was mapped tightly associated with the peak of QTsg.osu-3A. However, allelic variation in TaMFT-A1 between the two winter wheat cultivars differed from that was observed in spring wheat cultivars. There were 87 SNPs (single nucleotide polymorphisms) and 12 indels (insertions/deletions) in TaMFT-A1 between the Jagger allele for high germination and the 2174 allele for low germination in the after-ripened seeds, in comparison with 2 SNPs between the two alleles for differential pre-harvest sprouting in spring wheat cultivars. The Jagger TaMFT-A1 allele is a novel haplotype and appears extensively in winter wheat cultivars. TaMFT-A1 transcript levels were up-regulated by high temperature but down-regulated by low temperature or seed storage time. These findings suggest that TaMFT-A1 may invoke different mechanisms for controlling seed dormancy/germination among winter wheat cultivars. PMID:24069187

Lei, Lei; Zhu, Xinkai; Wang, Shuwen; Zhu, Meirong; Carver, Brett F; Yan, Liuling

2013-01-01

246

The role of thioredoxin h in protein metabolism during wheat (Triticum aestivum L.) seed germination.  

PubMed

Thioredoxin h can regulate the redox environment in the cell and play an important role in the germination of cereals. In the present study, the thioredoxin s antisense transgenic wheat with down-regulation of thioredoxin h was used to study the role of thioredoxin h in protein metabolism during germination of wheat seeds, and to explore the mechanism of the thioredoxin s antisense transgenic wheat seeds having high resistance to pre-harvest sprouting. The qRT-PCR results showed that the expression of protein disulfide isomerase in the thioredoxin s antisense transgenic wheat was up-regulated, which induced easily forming glutenin macropolymers and the resistance of storage proteins to degradation. The expression of serine protease inhibitor was also up-regulated in transgenic wheat, which might be responsible for the decreased activity of thiocalsin during the germination. The expression of WRKY6 in transgenic wheat was down-regulated, which was consistent with the decreased activity of glutamine oxoglutarate aminotransferase. In transgenic wheat, the activities of glutamate dehydrogenase, glutamic pyruvic transaminase and glutamic oxaloacetic transaminase were down-regulated, indicating that the metabolism of amino acid was lower than that in wild-type wheat during seed germination. A putative model for the role of thioredoxin h in protein metabolism during wheat seed germination was proposed and discussed. PMID:23562797

Guo, Hongxiang; Wang, Shaoxin; Xu, Fangfang; Li, Yongchun; Ren, Jiangping; Wang, Xiang; Niu, Hongbin; Yin, Jun

2013-06-01

247

Effect of Storage Conditions and Storage Periods on Seed Germination in Eleven Populations of Swertia chirayita: A Critically Endangered Medicinal Herb in Himalaya  

PubMed Central

Effect of different storage conditions (room temperature, 4°C, and ?15°C) and different storage periods over 24 months on seed germination in Swertia chirayita collected from different altitudes in Sikkim Himalaya was determined. Multivariate ANOVA revealed significant (P < 0.0001) effect of storage condition and storage period on seed germination and mean germination time. Seed germination percentage significantly (P < 0.01) varied between 87.78% (Sc5) and 100% (Sc2) during initial testing. Comparatively, high seed germination, low mean germination time, and low rate of fall in seed germination percentage in seeds stored at 4°C over different storage period were recorded. In addition, above 50% seed germination in majority of the populations even after 24 months of storage suggests 4°C as the most appropriate storage condition for long-term storage of seeds of S. chirayita. PMID:22619581

Pradhan, Bharat K.; Badola, Hemant K.

2012-01-01

248

Effect of microorganisms and nitrogen on the allelopathy of sorghum residues and the germination of wheat seeds  

Microsoft Academic Search

This experiment examines the effect of microorganisms on the allelopathic chemicals from sorghum residues on the germination of wheat seeds. Sorghum plants were decomposed to obtain an extract from the residue. This residue was used to germinate wheat seeds at each nitrogen level. The different nitrogen levels did not appear to change the effect that the allelopathic chemicals had on

Terry S. Phillips

249

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

250

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 and ABA pathways. Keywords: microRNA, seed germination, ARF10, miR160, ABA, auxin. Introduction micro during many stages of plant growth development. ARF10, ARF16 and ARF17 are targeted by microRNA160 (mi

Montgomery, Tai

251

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

252

Effects of Helminthosporium victoriae Toxin on Germination and Aleurone Secretion by Resistant and Susceptible Seeds.  

PubMed

Oat seeds of cultivars susceptible and resistant to Helminthosporium victoriae were held for various times in pathogen-produced, host-specific toxin solutions; control seeds were in water. Seeds were then washed thoroughly and incubated on moist paper, or dried and stored for 2-3 weeks before germination was attempted. In both cases, germination of susceptible seeds was prevented by previous exposure to toxin for 1 hour or more. Control seeds and treated resistant seeds grew normally. Toxin did not affect O(2) uptake or loss of carbohydrates from seeds for the first 12 hours of imbibition. After 12 hours, toxin-treated susceptible seeds had higher respiration and lost more carbohydrates than did control seeds. Experiments with embryoless seeds showed that toxin blocked synthesis and secretion of alpha-amylase by susceptible but not by resistant aleurone cells. Resting aleurone cells were exposed briefly to toxin, then dried and stored until all toxin was gone. Susceptible aleurone cells treated in this way failed to produce alpha-amylase following exposure to gibberellic acid, while controls and resistant treated aleurone tissues produced amylase. Susceptibility or resistance to toxin appears to be expressed in resting and metabolically active tissues. PMID:16657348

Samaddar, K R; Scheffer, R P

1970-05-01

253

The Antioxidant System of Wheat Seeds during Germination  

Microsoft Academic Search

The dynamics of peroxidase activity and antioxidant contents in wheat seeds were studied in the course of 24-hour swelling at 5°C (group 1) and 23°C (group 2). Both parameters were 1.5 times higher in seeds of the first group. In the same seeds, peroxidase activity in the endosperm and seed coat increased by factors of 1.5 and 1.8, respectively. Catalytic

V. V. Rogozhin; V. V. Verkhoturov; T. T. Kurilyuk

2001-01-01

254

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

255

Effect of germination of legume seeds on chemical composition and on protein and energy utilization in rats  

Microsoft Academic Search

Chemical composition of soybeans, lupin seeds and black beans, and protein utilization and energy digestibility of soybeans and lupin seeds determined in a rat model, were compared before and after a 48-h germination. Black beans had a much higher starch content and lower levels of low-molecular-weight (LMW) sugars than soybeans and lupin seeds. Lupin seeds had about twice as much

C. M. Donangelo; L. C. Trugo; N. M. F. Trugo; B. O. Eggum

1995-01-01

256

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

257

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

258

In-depth proteomic analysis of rice embryo reveals its important roles in seed germination.  

PubMed

Seed germination is a complex physiological process that allows the seed embryo to grow and develop into a photosynthetic organism. The two major constituents of rice seed include the embryo and endosperm, with embryo being of much significance despite its small size. In this study, we conducted a systematic proteomic analysis of the embryos dissected from rice seed at different stages of germination through a combination of gel-based and gel-free strategies. In total, 343 differentially expressed proteins were identified. Among them, 191 were decreased and 152 were increased in terms of expression levels. All these proteins could be sorted into 11 functional groups based on MapMan analysis. Some starch biosynthesis-related enzymes such as starch branching enzyme, granule-bound starch synthase 1 and starch synthase increased during the early stage of germination and then decreased at the late stage, which was similar to the expressional patterns of glycolysis-related enzymes. However, tricarboxylic acid cycle-related enzymes only increased at the later stage. It was also found that sucrose might be an important intermediate for the biosynthesis of starch in embryos. Furthermore, gel-based proteomic analysis of the dissected endosperm showed that the biological processes in the endosperm were heavily regulated by the embryo. This study could provide some new insights into the distinct roles of the embryo and endosperm in rice seed germination. PMID:25231964

Han, Chao; He, Dongli; Li, Ming; Yang, Pingfang

2014-10-01

259

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, Andre L. W.; Floh, Eny I. S.

2011-01-01

260

Dynamic proteomics emphasizes the importance of selective mRNA translation and protein turnover during Arabidopsis seed germination.  

PubMed

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 [(35)S]-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

261

TEMPERA TURA E SUBSTRA TO PARA O TESTE DE GERMINAÇÃO DE SEMENTES DE PINHÃO-MANSO Temperature and substrate for the germination test of physic nut seeds  

Microsoft Academic Search

Official rules for seed analysis don t establish criteria to execute germination tests for all species. This way, the aim of this research was to determinate the substrate, temperature and counting time for the germination test of physic nut seeds. For the germination test, four replications of 20 seeds were used, evaluating daily the normal seedlings until the end of

Cibele Chalita Martins; Carla Gomes Machado; Raquel Cavasini

262

Germination traits explain soil seed persistence across species: the case of Mediterranean annual plants in cereal fields  

PubMed Central

Background and Aims Seed persistence in the soil under field conditions is an important issue for the maintenance of local plant populations and the restoration of plant communities, increasingly so in the light of rapidly changing land use and climate change. Whereas processes important for dispersal in space are well known, knowledge of processes governing dispersal in time is still limited. Data for morphological seed traits such as size have given contradictory results for prediction of soil seed persistence or cover only a few species. There have been few experimental studies on the role of germination traits in determining soil seed persistence, while none has studied their predictive value consistently across species. Delayed germination, as well as light requirements for germination, have been suggested to contribute to the formation of persistent seed banks. Moreover, diurnally fluctuating temperatures can influence the timing of germination and are therefore linked to seed bank persistence. Methods The role of germination speed measured by T50 (days to germination of 50 % of all germinated seeds), light requirement and reaction to diurnally fluctuating temperatures in determining seed persistence in the soil was evaluated using an experimental comparative data set of 25 annual cereal weed species. Key Results It is shown that light requirements and slow germination are important features to maintain seeds ungerminated just after entering the soil, and hence influence survival of seeds in the soil. However, the detection of low diurnally fluctuating temperatures enhances soil seed bank persistence by limiting germination. Our data further suggest that the effect of diurnally fluctuating temperatures, as measured on seeds after dispersal and dry storage, is increasingly important to prevent fatal germination after longer burial periods. Conclusions These results underline the functional role of delayed germination and light for survival of seeds in the soil and hence their importance for shaping the first part of the seed decay curve. Our analyses highlight the detection of diurnally fluctuating temperatures as a third mechanism to achieve higher soil seed persistence after burial which interacts strongly with season. We therefore advocate focusing future research on mechanisms that favour soil seed persistence after longer burial times and moving from studies of morphological features to exploration of germination traits such as reaction to diurnally fluctuating temperatures. PMID:21224268

Saatkamp, Arne; Affre, Laurence; Dutoit, Thierry; Poschlod, Peter

2011-01-01

263

The effects of cis-trans ABA on embryo germination and seed dormancy in wheat  

Microsoft Academic Search

Pre-harvest sprouting of wheat grain can cause economic losses especially in cultivars with low levels of seed dormancy. The\\u000a aim of this study was to determine genotype differences in embryo sensitivity to germination in response to exogenous (+\\/–)\\u000a cis-trans ABA treatments at different concentrations. Six white and four red seed-colored bread wheat genotypes that differed in dormancy\\u000a were grown in

J. M. Nyachiro; F. R. Clarke; R. M. DePauw; R. E. Knox; K. C. Armstrong

2002-01-01

264

Seed germination of two cattail ( Typha ) species as A function of Everglandes nutrient levels  

Microsoft Academic Search

Sawgrass (Cladium jamaicense) is being replaced by cattails (Typha domingensis andTypha latifolia) in Water Conservation Area 2A (WCA 2A) of the Florida Everglades. This replacement coincides with changes in nutrients in\\u000a WCA 2A. Investigating seed germination ofTypha in response to different nutrient levels, focusing on phosphate, might help in understanding how this replacement occurs.\\u000a Three sets of experiments with seed

Herbert Stewart; Shi Li Miao; Marsha Colbert; Charles E. Carraher

1997-01-01

265

Soluble Sugar Contents, Germination, and Vigor of Soybean Seeds in Response to Drought Stress  

Microsoft Academic Search

A greenhouse experiment was conducted to study the effect of drought stress on seed germination and vigor of soybean in relation with soluble sugars. Three drought stress treatments, well-watered treatment (WW), gradual stress (GS) imposed prior to severe stress treatment, and sudden severe stress (SS), were imposed on soybean plants at beginning seed fill stage (R5) for 20–23 d. Drought

N. H. Samarah; R. E. Mullen; I. Anderson

2009-01-01

266

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

267

Seed germination of Fragaria vesca L. From atypical ecotopes of West Siberia  

Microsoft Academic Search

Seed formation and seed germination rate were established to be essentially higher in Fragaria vesca L. populations growing in the ecotopes which are atypical for wood strawberry than in the standard ecotopes for the species.\\u000a Having equal capabilities for cross-pollination and self-pollination, the plants exhibit higher level of xenogamy than autogamy\\u000a when growing in atypical ecotopes. Xenogamy predomination promotes the

S. O. Baturin

2009-01-01

268

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

Microsoft Academic Search

Cirsium arvense and Lepidium latifolium are species that can aggressively invade wetland margins and potentially reduce biodiversity and alter ecosystem function.\\u000a Although expansion of these species primarily occurs via rhizomatous growth, seeds are thought to be important in initial\\u000a establishment. We conducted this study to investigate differences in seed germination of C. arvense and L. latifolium in montane wetlands of

Murray K. Laubhan; Terry L. Shaffer

2006-01-01

269

Germination and Emergence of Primed Grass Seeds Under Field and Simulated-field Temperature Regimes  

Microsoft Academic Search

Seed priming may enhance establishment success of cool-season range grasses which must compete with annual weeds for early spring moisture. Previous priming studies have confirmed germination rate enhancement for these species but relative treatment effects under field-temperature conditions have not been assessed. We primed seeds of thickspike wheatgrass [Elymus lanceolatus(Scribn. and J. G. Smith) Gould], bluebunch wheatgrass [Pseudoroegneria spicata(Pursh) Löve],

Stuart P. Hardegree; Steven S. Van Vactor

2000-01-01

270

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

271

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

272

Partial purification and properties of lipase from germinating seeds of Jatropha curcas L  

Microsoft Academic Search

Lipase present in the seeds of Jatropha curcas L. was isolated and some of its properties studied. Lipase activity was detected in both dormant and germinating seeds. The\\u000a lipase was partially purified using a combination of ammonium sulfate precipitation and ultrafiltration, which increased the\\u000a relative activity of the lipase by 28- and 80-fold, respectively. The lipase hydrolyzed palm kernel, coconut,

Roland D. Abigor; Patrick O. Uadia; Thomas A. Foglia; Michael J. Haas; Karen Scott; Brett J. Savary

2002-01-01

273

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

274

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

275

Cadmium impairs mineral and carbohydrate mobilization during the germination of bean seeds.  

PubMed

The germination rate, mineral (Ca, Fe, K, Mn) and carbohydrate (starch, soluble sugars, sucrose, glucose, fructose) contents and hydrolase activities in cotyledons and embryonic axes of bean seeds subjected to cadmium stress were investigated. Compared to the control, Cd caused a reduction in germination percent, embryo growth and in distribution of biomass, mineral and sugars between cotyledon and embryonic axis and inhibited the activities of alpha-amylase and invertases: soluble acid (INV-AS), soluble neutral (INV-NS), cell wall bound acid (INV-AW). Moreover, the solute leakage into the germination medium was also used as bioindicator parameter to evaluate the toxicity of cadmium accumulation, which increased in different tissues of germinating seeds in the duration of treatment and provoked nutrient loss and, thereby, electrical conductivity enhancement in the imbibition medium. This was correlated with an impairment of membrane integrity, as evidenced by high malondialdehyde (MDA) content and lipoxygenase (LOX) activity in Cd-poisoned embryo. The contribution of solute loss at the expense of growing embryonic axis to failure in reserve mobilization after Cd exposure is emphasized in association with the delay in seed germination. PMID:20138361

Sfaxi-Bousbih, Amira; Chaoui, Abdelilah; El Ferjani, Ezzedine

2010-09-01

276

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

277

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

278

In vitro Asymbiotic Germination of Immature Seed and Formation of Protocorm by Cephalanthera falcata (Orchidaceae)  

PubMed Central

• Background and Aims Many Orchidaceous species are threatened globally by development and over-collection from their natural habitats for horticultural purposes. Artificial propagation from seeds is difficult in most terrestrial orchids native to temperate regions. Seed production is another limiting factor in the artificial propagation for these species because of the lessened probability of pollination and the destruction of fruit by insect larvae. Members of the genus Cephalanthera are distributed across Europe, Asia and North America. C. falcata is a temperate species of East Asia and an endangered species in Japan. As successful propagation from seeds of this species has never been reported, a reproducible method is described here for seed production in situ and propagation using immature seeds in asymbiotic culture in vitro. • Methods Effects of hand-pollination and bagging treatment of ovaries were examined. Young capsules were collected every 10 d from 50 d after pollination until 120 d after pollination. Immature seeds obtained from these capsules were cultured asymbiotically on modified Kano medium and ND medium. Seed viability was examined within TTC (2,3,5-triphenyl tetrazolium chloride) test solution and histological observations were made on viable seeds by paraffin embedding at each collection stage. • Key Results and Conclusions Hand-pollination followed by bagging treatment of ovaries with aluminium foil was effective for insect control during fruit development, and successfully yielded capsules. Of the capsules, 74·5 % survived to full maturity. The highest frequency (39·8 %) of seed germination was obtained with seeds harvested 70 d after pollination. The frequency declined with progress of seed maturity on the mother plant. Minimal germination was observed with seeds harvested 100 d or later after pollination. Histological observation suggests that accumulation of such substances as lignin in the inner integument surrounding the embryo during seed maturation plays an important role in induction of dormancy. PMID:17071633

YAMAZAKI, JUN; MIYOSHI, KAZUMITSU

2006-01-01

279

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

280

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

E-print Network

and embryonic axis of germinating pea seeds. An early onset and sequential induction of ACC biosynthesis ± Signalling Introduction The gaseous plant hormone ethylene exerts profound eects in plants throughout. 1998), and in etiolated pea seedlings (Peck and Kende 1995; Peck et al. 1998). Thus, in several tissues

Leubner, Gerhard

281

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

282

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

283

Genome-wide network model capturing seed germination reveals coordinated regulation  

E-print Network

conservation in flowering plants. The topology of the SeedNet graph reflects the biological process, in phase transitions. The phase transition regulators SERRATE and EARLY FLOWERING IN SHORT DAYS from cues such as chilling. Germination is principally regulated by the hormones gibberellic acid (GA

Toronto, University of

284

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

285

Salinity effects on germination, growth, and seed production of the halophyte Cakile maritima  

Microsoft Academic Search

Cakile maritima (Brassicaceae) is a halophyte that thrives on dunes along the Tunisian seashore. Besides its ecological interest for soil fixation, this plant produces seeds rich in lipids (40% on dry weight basis), making it a potential source of oil for industrial use. The purpose of the present work was to study the salt tolerance of this species at germination,

Ahmed Debez; Karim Ben Hamed; Claude Grignon; Chedly Abdelly

2004-01-01

286

The effects of maternal salinity and seed environment on germination and growth in Iris hexagona  

Microsoft Academic Search

Seed germination and seedling establishment are determined by local environmental conditions as well as by the environment of the parental generation, resulting in a type of trans- generational phenotypic plasticity known as an inherited environmental effect. Parental effects should be adaptive in habitats where the selective environment is spatially and temporally predictable, and where parental effects confer a fitness advantage.

Peter A. Van Zandt; Susan Mopper

2004-01-01

287

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

288

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

289

Effect of Liquid Nitrogen Storage on Seed Germination of 51 Tree Species  

Microsoft Academic Search

Two liquid nitrogen storage experiments were performed on 51 tree species. In experiment 1, seeds of 9 western tree species were placed in a liquid nitrogen tank for 3 time periods: 24 hours, 4 weeks, and 222 days. A corresponding control sample accompanied each treatment. For three species, Calocedrus decurrens, Pinus jefferyi, and Pinus contorta, the germination percent was not

Jill R. Barbour; Bernard R. Parresol

290

Ecotoxicological effects of paracetamol on seed germination and seedling development of wheat ( Triticum aestivum L.)  

Microsoft Academic Search

In order to assess ecological risk of pharmaceutical compounds entering into agricultural ecosystems, toxic effects of paracetamol with therapeutic action on wheat (Triticum aestivum L.) were investigated as an example, using early growing and developmental indexes of wheat, including seed germination, shoot height and root length, peroxidase, superoxide dismutase, chlorophyll, and soluble protein in the seedlings. The results showed that

Jing An; Qixing Zhou; Fuhong Sun; Lei Zhang

2009-01-01

291

Effect of abscisic and gibberellic acids on malate synthase transcripts in germinating castor bean seeds  

Microsoft Academic Search

Several clones complementary to malate synthase mRNA have been identified in a complementary-DNA library to mRNA from castor bean endosperm. One of these clones has been used as a probe to measure levels of transcripts during seed germination and the effects of gibberellic acid and abscisic acid on these levels have been examined.

D. Rodriguez; J. Dommes; D. H. Northcote

1987-01-01

292

Experimental inbreeding reduces seed production and germination independent of fragmentation of populations of Swertia perennis  

Microsoft Academic Search

We studied effects of inbreeding on the early fitness measures seed production and germination in Swertia perennis L. (Gentianaceae), a locally abundant specialist of fen grasslands, which have been greatly fragmented in Switzerland. We further tested whether such effects differed between popula- tions of different size and isolation. We studied effects of free pollination, hand-outcrossing and hand-selfing on 160 plants

Judit Lienert; Markus Fischer

2004-01-01

293

Experimental inbreeding reduces seed production and germination independent of fragmentation of populations of Swertia perennis  

Microsoft Academic Search

We studied effects of inbreeding on the early fitness measures seed production and germination in Swertia perennis L. (Gentianaceae), a locally abundant specialist of fen grasslands, which have been greatly fragmented in Switzerland. We further tested whether such effects differed between populations of different size and isolation. We studied effects of free pollination, hand-outcrossing and hand-selfing on 160 plants in

Judit Lienert; Markus Fischer

2004-01-01

294

Water Uptake and Distribution in Germinating Tobacco Seeds Investigated in Vivo by Nuclear Magnetic  

E-print Network

Water Uptake and Distribution in Germinating Tobacco Seeds Investigated in Vivo by Nuclear Magnetic-Ludwigs-Universita¨t Freiburg, D­79104 Freiburg i. Br., Germany (K.M., B.K., G.L.-M.) The regulation of water uptake state-of-the-art methods showed that water distribution in the water uptake phases II and III

Leubner, Gerhard

295

The germination of freshly harvested seed of ripe and unripe barley and oats  

Microsoft Academic Search

Barley and oats were grown in a greenhouse and outside in the field to different stages of ripeness. After harvest the plants were threshed as soon as possible. The seeds were treated in different ways and sown immediately in a sand-bed. The kernels which germinated were counted.

Sigurd Andersen

1965-01-01

296

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

297

Influence of germination with different selenium solutions on nutritional value and cytotoxicity of lupin seeds.  

PubMed

The effect of different selenium solutions during germination of lupin seeds (Lupinus angustifolius L. cv. Zapaton) on the content of total selenium, protein, amino acids, soluble carbohydrates, total antioxidant activity, and cytotoxicity on HL-60 human leukemic cell line has been studied. Seeds were germinated in the presence of selenite (Na2SeO3) or selenate (Na2SeO4) solutions at different concentrations (0, 2, 4, 6, and 8 mg/L) for 5 days at either 20 or 25 degrees C. The addition of inorganic Se forms significantly increased Se content in lupin sprouts in a dose-dependent manner. The highest Se content in lupin sprouts was observed when germination was carried out with selenate solutions at 20 degrees C (11 microg/g of dw) or 25 degrees C (14 microg/g of dw). The Se-enriched sprouts presented an improvement in antioxidant activity (up to 117.8 and 103.5 micromol of Trolox/g of dw) as well as in essential amino acid content, and no cytotoxicity was observed on HL-60 human leukemic cells. Lupin seeds germinated with 8 mg/L selenate solutions for 5 days at 20 degrees C exhibited a higher germination rate (>90%) and a higher concentration of some essential amino acids than those obtained in selenite solutions in the same germination conditions. Therefore, the employment of selenate solutions at a concentration of 8 mg/L and germination for 5 days at 20 degrees C may be suggested for the production of Se-enriched lupin sprouts. PMID:19166293

Frias, Juana; Gulewicz, Piotr; Martínez-Villaluenga, Cristina; Pilarski, Rados?aw; Blazquez, Enrique; Jiménez, Begoña; Gulewicz, Krzysztof; Vidal-Valverde, Concepción

2009-02-25

298

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

299

Biotransformation of constituents of essential oils by germinating wheat seed  

Microsoft Academic Search

Wheat seeds, when exposed to essential oils, are able to metabolise certain monoterpenes. The actual amounts of the compounds and their derivatives in the endosperm and embryo of wheat seeds, after exposure to the monoterpenes were determined. Neral and geranial, which are the constituents of citral, are reduced and oxidised to the corresponding alcohols and acids. Similarly citronellal, pulegone and

Nativ Dudai; Olga Larkov; Eli Putievsky; Henri R Lerner; Uzi Ravid; Efraim Lewinsohn; Alfred M Mayer

2000-01-01

300

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

301

Seed reserve composition and mobilization during germination and early seedling establishment of Cereus jamacaru D.C. ssp. jamacaru (Cactaceae).  

PubMed

Cereus jamacaru, a Cactaceae found throughout northeast Brazil, is widely used as cattle food and as an ornamental and medicinal plant. However, there has been little information about the physiological and biochemical aspects involved in its germination. The aim of this study was to investigate its reserve mobilization during germination and early seedling growth. For this, C. jamacaru seeds were germinated in a growth chamber and collected at 0, 2, 4, 5, 6, 8 and 12 days after imbibition for morphological and biochemical analyses. Dry seeds had wrinkled seed coats and large, curved embryos. Lipids were the most abundant reserve, comprising approximately 55% and 65% of the dry mass for cotyledons and the hypocotylradicle axis, respectively. Soluble sugars and starch were the minor reserves, corresponding to approximately 2.2% of the cotyledons' dry mass, although their levels showed significant changes during germination. Soluble proteins corresponded to 40% of the cotyledons' dry mass, which was reduced by 81% at the final period of germination compared to dry seeds. C. jamacaru seed can be classified as an oil seed due to its high lipid content. Moreover, lipids were the main reserve mobilized during germination because their levels were strongly reduced after seed germination, while proteins were the second most utilized reserve in this process. PMID:22886166

Alencar, Nara L M; Innecco, Renato; Gomes-Filho, Enéas; Gallão, Maria Izabel; Alvarez-Pizarro, Juan C; Prisco, José T; Oliveira, Alexandre B De

2012-09-01

302

Germination of Acacia harpophylla (Brigalow) seeds in relation to soil water potential: implications for rehabilitation of a threatened ecosystem  

PubMed Central

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 germination of native plants on post-mining land may be an effective and economically viable solution in order to re-establish plant communities. However, due to their capacity to reproduce asexually, alternative rehabilitation approaches such as transplantation of whole soil-root compartments may become attractive for restoration ecologists to achieve safe, stable, and non-polluting ecosystems. PMID:24795847

Kailichova, Yolana; Baumgartl, Thomas

2014-01-01

303

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 germination of native plants on post-mining land may be an effective and economically viable solution in order to re-establish plant communities. However, due to their capacity to reproduce asexually, alternative rehabilitation approaches such as transplantation of whole soil-root compartments may become attractive for restoration ecologists to achieve safe, stable, and non-polluting ecosystems. PMID:24795847

Arnold, Sven; Kailichova, Yolana; Baumgartl, Thomas

2014-01-01

304

Seed germination of the Australian desert shrub Eremophila (Myoporaceae)  

Microsoft Academic Search

Eremophila is an Australian genus of 212 species ranging from prostrate shrubs to small trees, the great majority of which occur in\\u000a Western Australia. Recent interest in the genus’s germination strategies developed out of a need to seek rehabilitation techniques\\u000a for mine-site and rangeland areas. The genus is of special interest because of its broad geographic range and prominence in

Guy S. Richmond; Robert J. Chinnock

1994-01-01

305

Seeds Use Temperature Cues to Ensure Germination under Nurse-plant Shade in Xeric Kalahari Savannah  

PubMed Central

Background and Aims In arid environments many plant species are found associated with the canopies of woody perennials. Favourable conditions for establishment under canopies are likely to be associated with shade, but under canopies shade is distributed patchily and differs in quality. Diurnal temperature fluctuations and maximum temperatures could be reliable indicators of safe sites. Here, an examination is made as to whether canopy-associated species use temperature cues to germinate in shade patches, rather than matrix areas between trees. Methods The study was carried out in arid southern Kalahari savannah (Republic of South Africa). Perennial and annual species associated with Acacia erioloba trees and matrix species were germinated at temperature regimes resembling shaded and unshaded conditions. Soil temperature was measured in the field. Key Results Germination of all fleshy-fruited perennial acacia-associated species and two annual acacia-associated species was inhibited by the temperature regime resembling unshaded conditions compared with at least one of the regimes resembling shaded conditions. Inhibition in perennials decreased with seed mass, probably reflecting that smaller seedlings are more vulnerable to drought. Germination of matrix species was not inhibited by the unshaded temperature regime and in several cases it increased germination compared with shaded temperature regimes or constant temperature. Using phylogenetically independent contrasts a significant positive relationship was found between canopy association and the germination at shade temperatures relative to unshaded temperatures. Conclusions The data support the hypothesis that canopy species have developed mechanisms to prevent germination in open sun conditions. The results and data from the literature show that inhibition of germination at temperature regimes characteristic of open sun conditions can be found in fleshy-fruited species of widely divergent taxonomic groups. It is predicted that germination mechanisms to detect canopy shade based on temperature cues are widespread in species depending on nurse plants, especially bird-dispersed species. PMID:17259226

Kos, Martijn; Poschlod, Peter

2007-01-01

306

Antagonism between abscisic acid and gibberellins is partially mediated by ascorbic acid during seed germination in rice.  

PubMed

The antagonism between abscisic acid (ABA) and gibberellin (GA) plays a key role in controlling seed germination, but the mechanism of antagonism during this process is not known. In the associated study, we investigated the relationship among ABA, reactive oxygen species (ROS), ascorbic acid (ASC) and GA during rice seed germination. ROS production is reduced by ABA, which hence results in decreasing ASC accumulation during imbibition. GA accumulation was also suppressed by a reduced ROS and ASC level, whereas application of exogenous ASC can partially rescue seed germination from ABA treatment. Further results show that production of ASC, which acts as a substrate in GA biosynthesis, was significantly inhibited by lycorine which thus suppressed the accumulation of GA. Consequently, expression of GA biosynthesis genes was suppressed by the low levels of ROS and ASC in ABA-treated seeds. These studies reveal a new role for ASC in mediating the antagonism between ABA and GA during seed germination in rice. PMID:22516812

Ye, Nenghui; Zhang, Jianhua

2012-05-01

307

Role of thioproline on seed germination: interaction ROS-ABA and effects on antioxidative metabolism.  

PubMed

In this work we investigate the effect of the imbibition of pea seeds with different thioproline (TP) concentrations on the germination percentage and the early growth of the seedlings. The interaction between TP and hydrogen peroxide (H?O?) treatments is also analysed in order to test if any synergy in germination and growth occurs. Although the imbibition of pea seeds in the presence of TP did not significantly improve the germination percentage, TP and/or H?O? pre-treatments increased seedlings growth. This increase in seedling growth was reduced by abscisic acid (ABA) addition. Imbibition of pea seeds in the presence of ABA also reduced the endogenous H?O? contents of pea seedlings in control and TP-treated seeds. The incubation of pea seeds with TP and/or H?O? in presence or absence of ABA decreased the activity of H?O?-scavenging enzymes. The increase of the endogenous H?O? contents observed in TP and/or H?O? treatments in absence of ABA could be correlated with the decrease in these activities. Finally, the hormone profile of pea seedlings was investigated. The results show that the increase in seedling growth is correlated with a decrease in ABA in samples pre-treated with H?O? and TP + H?O?. Nevertheless, no significant differences in endogenous ABA concentration were observed with the TP pre-treatment. This paper suggests a relationship between endogenous H?O? contents and plant growth, so reinforcing the intricate crosstalk between reactive oxygen species (ROS) and plant hormones in seed germination signalling and early seedling development. PMID:22244306

Barba-Espin, Gregorio; Nicolas, Eduardo; Almansa, Maria Soledad; Cantero-Navarro, Elena; Albacete, Alfonso; Hernández, José Antonio; Díaz-Vivancos, Pedro

2012-10-01

308

Spatially and genetically distinct control of seed germination by phytochromes A and B.  

PubMed

Phytochromes phyB and phyA mediate a remarkable developmental switch whereby, early upon seed imbibition, canopy light prevents phyB-dependent germination, whereas later on, it stimulates phyA-dependent germination. Using a seed coat bedding assay where the growth of dissected embryos is monitored under the influence of dissected endosperm, allowing combinatorial use of mutant embryos and endosperm, we show that canopy light specifically inactivates phyB activity in the endosperm to override phyA-dependent signaling in the embryo. This interference involves abscisic acid (ABA) release from the endosperm and distinct spatial activities of phytochrome signaling components. Under the canopy, endospermic ABA opposes phyA signaling through the transcription factor (TF) ABI5, which shares with the TF PIF1 several target genes that negatively regulate germination in the embryo. ABI5 enhances the expression of phytochrome signaling genes PIF1, SOMNUS, GAI, and RGA, but also of ABA and gibberellic acid (GA) metabolic genes. Over time, weaker ABA-dependent responses eventually enable phyA-dependent germination, a distinct type of germination driven solely by embryonic growth. PMID:22948663

Lee, Keun Pyo; Piskurewicz, Urszula; Ture?ková, Veronika; Carat, Solenne; Chappuis, Richard; Strnad, Miroslav; Fankhauser, Christian; Lopez-Molina, Luis

2012-09-01

309

Exogenous 5-Aminolevulenic Acid Promotes Seed Germination in Elymus nutans against Oxidative Damage Induced by Cold Stress  

PubMed Central

The protective effects of 5-aminolevulenic acid (ALA) on germination of Elymus nutans Griseb. seeds under cold stress were investigated. Seeds of E. nutans (Damxung, DX and Zhengdao, ZD) were pre-soaked with various concentrations (0, 0.1, 0.5, 1, 5, 10 and 25 mg l?1) of ALA for 24 h before germination under cold stress (5°C). Seeds of ZD were more susceptible to cold stress than DX seeds. Both seeds treated with ALA at low concentrations (0.1–1 mg l?1) had higher final germination percentage (FGP) and dry weight at 5°C than non-ALA-treated seeds, whereas exposure to higher ALA concentrations (5–25 mg l?1) brought about a dose dependent decrease. The highest FGP and dry weight of germinating seeds were obtained from seeds pre-soaked with 1 mg l?1 ALA. After 5 d of cold stress, pretreatment with ALA provided significant protection against cold stress in the germinating seeds, significantly enhancing seed respiration rate and ATP synthesis. ALA pre-treatment also increased reduced glutathione (GSH), ascorbic acid (AsA), total glutathione, and total ascorbate concentrations, and the activities of superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR), whereas decreased the contents of malondialdehyde (MDA) and hydrogen peroxide (H2O2), and superoxide radical (O2•?) release in both germinating seeds under cold stress. In addition, application of ALA increased H+-ATPase activity and endogenous ALA concentration compared with cold stress alone. Results indicate that ALA considered as an endogenous plant growth regulator could effectively protect E. nutans seeds from cold-induced oxidative damage during germination without any adverse effect. PMID:25207651

Fu, Juanjuan; Sun, Yongfang; Chu, Xitong; Xu, Yuefei; Hu, Tianming

2014-01-01

310

Relationships Between Seed Weight, Germination Potential and Biochemical Reserves of Maritime Pine in Morocco: Elements for Tree Seedlings Improvement  

NASA Technical Reports Server (NTRS)

Selection of quality seeds in breeding programs can significantly improve seedling productivity. Germination and biochemical analyses on seeds from ten natural populations of maritime pine (Pinus pinaster Ait.) in Morocco reveals significant differences among populations in seed weight, germination characters and protein content in both dry seeds and megagametophytes. During germination, the mobilization of protein content in megagametophyte is significantly different among populations than sugar content. A strong positive correlation between the germination capacity and the protein content in both dry seeds and megagametophytes indicates that the best populations in term of germination capacity may also be the richest in protein content. The present study finds that seed weight is not a good indicator for quality seed selection, nor is it recommended to increase the degree of germinability. Our results suggest that the pine population in southern Morocco might have adapted to drought conditions as it is characterized by heavy seed weight and lower speed of protein content mobilization in megagametophyte compared to northern populations growing in temperate climate.

Wahid, Nadya; Bounoua, Lahouari

2011-01-01

311

The mobilization of defence mechanisms in the early stages of pea seed germination against Ascochyta pisi.  

PubMed

Ascochyta pisi is a necrotrophic pathogenic fungus, which mainly survives between seasons through infected seeds. Defence responses of pea embryo axes to A. pisi were investigated in the heterotrophic phase of seed germination and during the transition from the heterotrophic to the autotrophic phase. Germinated pea seeds, both non-inoculated and inoculated with A. pisi, were cultured in perlite for 96 h. Polarographic studies performed on intact embryo axes of germinating pea seeds infected with A. pisi showed a high respiratory intensity in time from 48 to 96 h after inoculation. Forty-eight-hour embryo axes of germinating pea seeds exhibited the highest respiration rate, which in infected axes was maintained at the following time points after inoculation. Moreover, at 72 and 96 h after inoculation, respiratory intensity was by 64% and 73% higher than in the control. Electron paramagnetic resonance analysis revealed a higher concentration of semiquinone free radicals with g values of g (||) = 2.0031 ± 0.0004 and g (?) = 2.0048 ± 0.0004 in infected axes than in the control. Generation of superoxide anion radical was also higher in infected axes than in the control but stronger at 72 and 96 h after inoculation. Starting from 72 h after infection, the level of Mn(2+) ions in infected axes decreased in relation to the control. At the same time, the highest activity of superoxide dismutase (EC 1.15.1.1) and catalase (EC 1.11.1.6) was observed in 72-h infected axes. In turn, the activity of peroxidase (EC 1.11.1.7) up to 72 h after infection was lower than in the control. In 48-h infected embryo axes, a very high level of pterocarpan pisatin was observed. Infection of germinating pea seeds with A. pisi restricted mainly the growth of the epicotyl, but did not inhibit the increase in length and fresh weight of root embryo axes versus cultivation time. These results indicate that in pea during the stages of seed germination and early seedling growth, protective mechanisms are induced in embryo axes against A. pisi. PMID:22274650

Morkunas, Iwona; Formela, Magda; Marczak, Lukasz; Stobiecki, Maciej; Bednarski, Waldemar

2013-02-01

312

Relationships Between Seed Germinability of Spergularia marina (Caryophyllaceae) and the Formation of Zonal Communities in an Inland Salt Marsh  

PubMed Central

• Background and Aims The formation of zonal communities may be attributed to differences in germination across the community and to timing of germination of seeds present in the seed bank. Our goals were two?fold: (1) to assess the annual germination pattern of Spergularia marina; and (2) to determine whether germination of S. marina differed across zonal communities. • Methods Fresh seeds were buried in an experimental garden in polyester bags. Bags were harvested monthly for 1 year and exposed to differing 12 h/12 h temperature regimes (5/15 °C, 5/25 °C, 15/25 °C and 20/35 °C) with a 12 h dark/12 h light photoperiod. Replicate seeds were exposed to 24 h dark. Seeds were also placed in different zonal communities to assess germinability in the field. • Key Results Spergularia marina has a primary physiological dormancy. Conditional dormancy occurs from December to May and non?dormancy from June to November. Field germination initiates in the spring when temperatures are cool and salinity is low due to flooding, and ceases in the summer when temperatures exceed germination requirements. Spergularia marina has a light requirement for germination. • Conclusions If seeds become buried in the field or are light inhibited by Phragmites australis, they will remain dormant until they receive an adequate amount of light for germination. Since S. marina can germinate across all zones in a salt?marsh community, the formation of zonal communities is not determined at the germination stage, but at some later stage of development. PMID:14672911

CARTER, CHRISTY T.; UNGAR, IRWIN A.

2004-01-01

313

Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon?  

PubMed

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species--the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener. PMID:18544070

Andersson, S; Månsby, E; Prentice, H C

2008-09-01

314

Germination ecology of eleven species of Geraniaceae and Malvaceae , with special reference to the effects of drying seeds  

Microsoft Academic Search

Germination and survival of water-impermeable seeds of 11 species of Geraniaceae and Malvaceae were monitored during dry storage and during burial in soil for up to 2.5 years. During dry storage, seeds of annual Geraniaceae became permeable and also lost their physiological dormancy. However, during burial in natural conditions, most seeds remained impermeable and viable, with no seasonal change in

Jozef A. Van Assche; Filip E. A. Vandelook

2006-01-01

315

Low intensive influence effect of the electromagnetic waves on the seed germination of winter crops, spring corn and forage grasses  

Microsoft Academic Search

The electrodynamic model of influence of electromagnetic energy on seeds of some Gramineae crops is developed. The technique of processing and the diagram of experimental installations are given. Application of microwave energy allowed to control successfully seed phytopathogenic infection, improved sowing qualities of the processed seeds (the germination increased by 16-17 %), promoting an intensification of growth processes.

P. Vas'ko; A. Ermolovich; V. Karpovich; E. Mikhalenko

2004-01-01

316

Seed Germination Ecology of Echinochloa glabrescens and Its Implication for Management in Rice (Oryza sativa L.)  

PubMed Central

Echinochloa glabrescens is a C4 grass weed that is very competitive with rice when left uncontrolled. The competitive ability of weeds is intensified in direct-seeded rice production systems. A better understanding is needed of factors affecting weed seed germination, which can be used as a component of integrated weed management in direct-seeded rice. This study was conducted to determine the effects of temperature, light, salt and osmotic stress, burial depth, crop residue, time and depth of flooding, and herbicide application on the emergence, survival, and growth of two populations [Nueva Ecija (NE) and Los Baños (IR)] of E. glabrescens. Seeds from both populations germinated at all temperatures. The NE population had a higher germination rate (88%) from light stimulation than did the IR population (34%). The salt concentration and osmotic potential required to inhibit 50% of germination were 313 mM and ?0.24 MPa, respectively, for the NE population and 254 mM and ?0.33 MPa, respectively, for the IR population. Emergence in the NE population was totally inhibited at 4-cm burial depth in the soil, whereas that of the IR population was inhibited at 8 cm. Compared with zero residue, the addition of 5 t ha?1 of rice residue reduced emergence in the NE and IR populations by 38% and 9%, respectively. Early flooding (within 2 days after sowing) at 2-cm depth reduced shoot growth by 50% compared with non-flooded conditions. Pretilachlor applied at 0.075 kg ai ha?1 followed by shallow flooding (2-cm depth) reduced seedling emergence by 94?96% compared with the nontreated flooded treatment. Application of postemergence herbicides at 4-leaf stage provided 85?100% control in both populations. Results suggest that integration of different strategies may enable sustainable management of this weed and of weeds with similar germination responses. PMID:24642568

Opena, Jhoana L.; Chauhan, Bhagirath S.; Baltazar, Aurora M.

2014-01-01

317

Effects of nitrification inhibitors on germination of various seeds in soil  

Microsoft Academic Search

The effects of 19 nitrificiation inhibitors on germination of seeds in soil were investigated. The nitrification inhibitors tested were sodium azide, potassium azide, potassium ethyl xanthate, nitrapyrin (N-Serve), etridiazole (Dwell), 3-mercapto-1,2,4-triazole (MT), 2-amino-4-chloro-6-methylpyrimidine (AM), 2,4-diamino-6-trichloromethyl-s-triazine, 2-mercaptobenzothiazole (MBT), 4-amino-1,2,4-triazole (ATC), sodium thiocarbonate (STC), guanylthiourea (ASU), thiourea (TU), dicyandiamide (DCD), sulfathiazole (STC), phenylacetylene, 2-ethynyl-pyridine, 3-methylpyrazole-l-carboxamide (MPC), and ammonium thiosulfate (ATS). Germination tests

J. M. Bremner; M. J. Krogmeier

1989-01-01

318

Effect of Noise on the Mathematical Parameters that Describe Isothermal Seed Germination.  

PubMed

A mathematical model is proposed to describe the isothermal germination rate of seeds as a function of time. All environmental parameters were held constant with the exception of the sound-pressure level and the frequency of the impinging sound waves. Each single frequency sound has its own set of mathematical parameters that describe the differential germination rate as a function of time. Frequencies of 100, 1000, 2000, 4000, and 9000 hertz as well as broad band noise, all at 100 decibels, were used in the experiments. PMID:16658758

Hageseth, G T

1974-04-01

319

Effects of Temperature, Water Potential, and Light on Germination Responses of Redroot Pigweed Seeds to Ethylene  

PubMed Central

The responses of redroot pigweed (Amaranthus retroflexus L.) seeds to nine ethylene concentrations between 0.5 and 50 microliters per liter were assessed at different temperatures and water potentials and in either continuous white light or darkness. Under all experimental treatments, the probit-transformed percentages increased linearly with the log of the ethylene concentration. In dormant seeds, the slope of the response line was unaffected by either light or water potential but increased with decreasing temperature. Conversely, the slope increased with increasing temperature in a partially afterripened seed lot. The ethylene response threshold for germination was little affected by temperature or light, ranging from 0.2 to 0.7 microliter per liter, but decreased to less than 0.1 microliter per liter at negative water potentials. Osmotic inhibition of germination at ?4 bars was largely relieved by 1 microliter per liter ethylene. Such interactions between ethylene and other environmental conditions may play an important role in the course of germination of soil-borne seeds. PMID:16661350

Schonbeck, Mark W.; Egley, Grant H.

1980-01-01

320

Role of protein and mRNA oxidation in seed dormancy and germination  

PubMed Central

Reactive oxygen species (ROS) are key players in the regulation of seed germination and dormancy. Although their regulated accumulation is a prerequisite for germination, the cellular basis of their action remains unknown, but very challenging to elucidate due to the lack of specificity of these compounds that can potentially react with all biomolecules. Among these, nucleic acids and proteins are very prone to oxidative damage. RNA is highly sensitive to oxidation because of its single-stranded structure and the absence of a repair system. Oxidation of mRNAs induces their decay through processing bodies or results in the synthesis of aberrant proteins through altered translation. Depending on the oxidized amino acid, ROS damage of proteins can be irreversible (i.e., carbonylation) thus triggering the degradation of the oxidized proteins by the cytosolic 20S proteasome or can be reversed through the action of thioredoxins, peroxiredoxins, or glutaredoxins (cysteine oxidation) or by methionine sulfoxide reductase (methionine oxidation). Seed dormancy alleviation in the dry state, referred to as after-ripening, requires both selective mRNA oxidation and protein carbonylation. Similarly, seed imbibition of non-dormant seeds is associated with targeted oxidation of a subset of proteins. Altogether, these specific features testify that such oxidative modifications play important role in commitment of the cellular functioning toward germination completion. PMID:23579315

El-Maarouf-Bouteau, Hayat; Meimoun, Patrice; Job, Claudette; Job, Dominique; Bailly, Christophe

2013-01-01

321

Effect of Temperature, Light and Salinity on Seed Germination and Radicle Growth of the Geographically Widespread Halophyte Shrub Halocnemum strobilaceum  

PubMed Central

Background and Aims The small leafy succulent shrub Halocnemum strobilaceum occurs in saline habitats from northern Africa and Mediterranean Europe to western Asia, and it is a dominant species in salt deserts such as those of north-west China. The effects of temperature, light/darkness and NaCl salinity were tested on seed germination, and the effects of salinity were tested on seed germination recovery, radicle growth and radicle elongation recovery, using seeds from north-west China; the results were compared with those previously reported on this species from ‘salt steppes’ in the Mediterranean region of Spain. Methods Seed germination was tested over a range of temperatures in light and in darkness and over a range of salinities at 25 °C in the light. Seeds that did not germinate in the NaCl solutions were tested for germination in deionized water. Seeds from which radicles had barely emerged in deionized water were transferred to NaCl solutions for 10 d and then back to deionized water for 10 d to test for radicle growth and recovery. Key Results Seeds germinated to higher percentages in light than in darkness and at high than at low temperatures. Germination percentages decreased with an increase in salinity from 0·1 to 0·75 m NaCl. Seeds that did not germinate in NaCl solutions did so after transfer to deionized water. Radicle elongation was increased by low salinity, and then it decreased with an increase in salinity, being completely inhibited by ?2·0 m NaCl. Elongation of radicles from salt solutions <3·0 m resumed after seedlings were transferred to deionized water. Conclusions The seed and early seedling growth stages of the life cycle of H. strobilaceum are very salt tolerant, and their physiological responses differ somewhat between the Mediterranean ‘salt steppe’ of Spain and the inland cold salt desert of north-west China. PMID:17428834

Qu, Xiao-Xia; Huang, Zhen-Ying; Baskin, Jerry M.; Baskin, Carol C.

2008-01-01

322

An extracellular lipid transfer protein is relocalized intracellularly during seed germination.  

PubMed

Plant lipid transfer proteins (LTPs) constitute a family of small proteins recognized as being extracellular. In agreement with this notion, several lines of evidence have shown the apoplastic localization of HaAP10, a LTP from Helianthus annuus dry seeds. However, HaAP10 was recently detected intracellularly in imbibing seeds. To clarify its distribution, immunolocalization experiments were performed during the course of germination and confirmed its intracellular localization upon early seed imbibition. Further assays using a hydrophobic dye, FM4-64, inhibitors of vesicular traffic, and immunolocalization of the pectin rhamnogalacturonan-II, allowed the conclusion that endocytosis is activated as soon as seed imbibition starts. Furthermore, this study demonstrated that HaAP10 is endocytosed throughout imbibition. Biochemical and cellular approaches indicate that the intracellular fraction of this LTP appears associated with oil bodies and some evidence also suggest its presence in glyoxysomes. So, HaAP10 is apoplastic in dry seeds and upon imbibition is rapidly internalized and relocalized to organelles involved in lipid metabolism. The results suggest that HaAP10 may be acting as a fatty acid shuttle between the oil body and the glyoxysome during seed germination. This concept is consistent with the initial proposition that LTPs participate in the intracellular transfer of lipids which was further denied based on their apparent extracellular localization. This report reveals for the first time the relocalization of a lipid transfer protein and opens new perspectives on its role. PMID:23162115

Pagnussat, Luciana; Burbach, Christian; Baluska, Frantisek; de la Canal, Laura

2012-11-01

323

Citric acid modifies surface properties of commercial CeO2 nanoparticles reducing their toxicity and cerium uptake in radish (Raphanus sativus) seedlings.  

PubMed

Little is known about the mobility, reactivity, and toxicity to plants of coated engineered nanoparticles (ENPs). Surface modification may change the interaction of ENPs with living organisms. This report describes surface changes in commercial CeO2 NPs coated with citric acid (CA) at molar ratios of 1:2, 1:3, 1:7, and 1:10 CeO2:CA, and their effects on radish (Raphanus sativus) seed germination, cerium and nutrients uptake. All CeO2 NPs and their absorption by radish plants were characterized by TEM, DLS, and ICP-OES. Radish seeds were germinated in pristine and CA coated CeO2 NPs suspensions at 50mg/L, 100mg/L, and 200mg/L. Deionized water and CA at 100mg/L were used as controls. Results showed ? potential values of 21.6 mV and -56 mV for the pristine and CA coated CeO2 NPs, respectively. TEM images showed denser layers surrounding the CeO2 NPs at higher CA concentrations, as well as better distribution and smaller particle sizes. None of the treatments affected seed germination. However, at 200mg/L the CA coated NPs at 1:7 ratio produced significantly (p ? 0.05) more root biomass, increased water content and reduced by 94% the Ce uptake, compared to bare NPs. This suggests that CA coating decrease CeO2 NPs toxicity to plants. PMID:24231324

Trujillo-Reyes, J; Vilchis-Nestor, A R; Majumdar, S; Peralta-Videa, J R; Gardea-Torresdey, J L

2013-12-15

324

Germination, osmotic adjustment, and antioxidant enzyme activities of gibberellin-pretreated Picea asperata seeds under water stress  

Microsoft Academic Search

Germination of dragon spruce (Picea asperata Mast.) seeds pretreated with gibberellin (GA) in response to water stress and changes in the levels of osmotic adjustments\\u000a as well as in activities of antioxidant enzymes were investigated. With decreasing water potential caused by increasing concentrations\\u000a of PEG 6000, germination percentage and germination index decreased gradually; the decrease was especially prominent under\\u000a the

Y. Yang; Q. Liu; G. X. Wang; X. D. Wang; J. Y. Guo

2010-01-01

325

Interacting infl uence of cold stratifi cation treatment and osmotic potential on seed germination of Triglochin maritima L  

Microsoft Academic Search

Th e eff ect of cold stratifi cation treatment and isoosmotic NaCl and polyethyleneglycol (PEG) concentrations on germination of Triglochin maritima seeds was assessed. Th e highest (400 mM) NaCl concentration caused a signifi cant decrease in germination percentage and no germination was observed at the two highest (64 and 128 mM) PEG concentrations. Th e large diff erence in

Gederts Ievinsh

2007-01-01

326

Loss of desiccation tolerance in Copaifera langsdorffii Desf. seeds during germination.  

PubMed

This study evaluated the loss of desiccation tolerance in C. langsdorffii seeds during the germination process. Seeds were imbibed for 24, 48, 72, 96, 120 and 144 hours and dried to the initial moisture content, kept in this state for 3 days after which they were submitted to pre-humidification and rehydration. Ultraestructural evaluations were done aiming to observe the cell damage caused by the dry process. Desiccation tolerance was evaluated in terms of the percentage of normal seedlings. Seeds not submitted to the drying process presented 61% of normal seedlings, and after 24 hours of imbibition, followed by drying, the seeds presented the same percentage of survival. However, after 48 hours of imbibition, seeds started to lose the desiccation tolerance. There was twenty six percent of normal seedlings formed from seeds imbibed for 96 hours and later dried and rehydrated. Only 5% of seeds imbibed for 144 hours, dried and rehydrated formed normal seedlings. At 144 hours of imbibition followed the dry process, there was damage into the cell structure, indicating that the seeds were unable to keep the cell structure during the drying process. Copaifera langsdorffii seeds loses the desiccation tolerance at the start of Phase 2 of imbibition. PMID:25166338

Pereira, W V S; Faria, J M R; Tonetti, O A O; Silva, E A A

2014-05-01

327

Arabinan Metabolism during Seed Development and Germination in Arabidopsis  

Microsoft Academic Search

Arabinans are found in the pectic network of many cell walls, where, along with galactan, they are present as side chains of Rhamnogalacturonan l. Whilst arabinans have been reported to be abundant polymers in the cell walls of seeds from a range of plant species, their proposed role as a storage reserve has not been thoroughly investigated. In the cell

Leonardo D. Gomez; Clare G. Steele-King; Louise Jones; Jonathan M. Foster; Supachai Vuttipongchaikij; S. J. McQueen-Mason

2009-01-01

328

Seed reserve composition in 19 tree species of a tropical deciduous forest in Mexico and its relationship to seed germination and seedling growth  

PubMed Central

Background and Aims The size and composition of seed reserves may reflect the ecological strategy and evolutionary history of a species and also temporal variation in resource availability. The seed mass and composition of seed reserves of 19 co-existing tree species were studied, and we examined how they varied among species in relation to germination and seedling growth rates, as well as between two years with contrasting precipitation (652 and 384 mm). Methods Seeds were collected from a tropical deciduous forest in the northwest of Mexico (Chamela Biological Station). The seed dry mass, with and without the seed coat, and the concentrations of lipids, nitrogen and non-structural carbohydrates for the seed minus seed coat were determined. The anatomical localization of these reserves was examined using histochemical analysis. The germination capacity, rate and lag time were determined. The correlations among these variables, and their relationship to previously reported seedling relative growth rates, were evaluated with and without phylogenetic consideration. Key Results There were interannual differences in seed mass and reserve composition. Seed was significantly heavier after the drier year in five species. Nitrogen concentration was positively correlated with seed coat fraction, and was significantly higher after the drier year in 12 species. The rate and lag time of germination were negatively correlated with each other. These trait correlations were also supported for phylogenetic independent contrasts. Principal component analysis supported these correlations, and indicated a negative association of seedling relative growth rate with seed size, and a positive association of germination rate with nitrogen and lipid concentrations. Conclusions Nitrogen concentration tended to be higher after the drier year and, while interannual variations in seed size and reserve composition were not sufficient to affect interspecific correlations among seed and seedling traits, some of the reserves were related to germination variables and seedling relative growth rate. PMID:21385781

Soriano, Diana; Orozco-Segovia, Alma; Marquez-Guzman, Judith; Kitajima, Kaoru; Gamboa-de Buen, Alicia; Huante, Pilar

2011-01-01

329

DOI:10.2298/ABS0702125N CYTOKININSAND UREA DERIVATIVES STIMULATE SEED GERMINATION IN LOTUS CORNICULATUS L.  

E-print Network

Abstract – We studied the effects of various cytokinins and urea derivatives on germination of aged seeds of in Lotus corniculatus L. The following substances were applied: N 6-isoprenoid cytokinins (isopentenyl adenine and zeatin), adenine sulfate, N 6-aromatic cytokinins (kinetin, benzyladenine) and their N 9-ribosides, N-benzyl-9-(2tetrahydropyranyl)adenine, and urea derivatives (diphenylurea, thidiazuron, and chloro-pyridyl phenylurea). With the exception of adenine sulfate, all cytokinins increased the percentage of seed germination up to twofold, depending on their kind and concentration. It is concluded that cytokinins may be among the missing factors in aged seeds of L. corniculatus contributing to the implementation of their full germination potential. They could be used to improve germination of both freshly harvested and aged seed samples, if necessary.

Radomirka Nikoli?; Nevena Miti?; Suzana Živkovi?; D. Grubiši?; Mirjana Neškovi?

330

Rhythmic increase in DNA content and incorporation of [ 3 H]thymidine in the developing wheat embryo during seed germination  

Microsoft Academic Search

The DNA content and incorporation of [3H]thymidine into DNA have been studied during the development of Triticum aestivum (L.) embryo at various stages of seed germination up to 102 h (18°C). The DNA content of the embryos increased in a rhythmic way, when superimposed on an increasing basal content of DNA from 12 h onwards of germination. A temporary depression

S. P. Yadav

1976-01-01

331

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

E-print Network

, including seed germination, elongation growth, and fruit ripening. Here, we report direct in vivo evidence weakening and radicle elongation and were inhibited by the germination-inhibiting hormone abscisic acid. Both effects were reversed by gibberellin. Distinct and tissue-specific target sites of Ã?OH attack

Leubner, Gerhard

332

Solar irradiation of the seed germination stimulant karrikinolide produces two novel head-to-head cage dimers.  

PubMed

Karrikinolide is a naturally derived potent seed germination stimulant that is responsible for triggering the germination of numerous plant species from various habitats around the world. We now report that solar irradiation of karrikinolide yields two novel head-to-head cage photodimers with the formation, stability and bioactivity of both presented herein. PMID:22514031

Scaffidi, Adrian; Waters, Mark T; Skelton, Brian W; Bond, Charles S; Sobolev, Alexandre N; Bythell-Douglas, Rohan; McKinley, Allan J; Dixon, Kingsley W; Ghisalberti, Emilio L; Smith, Steven M; Flematti, Gavin R

2012-05-28

333

Regulation of cell cycle activity in the embryo of barley seeds during germination as related to grain hydration  

Microsoft Academic Search

Various studies indicate that cell division is a post- germination phenomenon, with radicle protrusion oc- curring by cell elongation, while others demonstrate that induction of the cell cycle occurs in osmo- conditioned seeds prior to radicle growth. The aim of the present work was to investigate the occurrence of the cell cycle during germination as related to grain hydration, using:

Emmanuel Gendreau; S. Romaniello; S. Barad; J. Leymarie; R. Benech-Arnold; F. Corbineau

2008-01-01

334

Proteases associated with programmed cell death of megagametophyte cells after germination of white spruce ( Picea glauca ) seeds  

Microsoft Academic Search

During post-germinative seedling growth, the major storage organ of the white spruce (Picea glauca) seed, the megagametophyte, undergoes programmed cell death (PCD). Protease activities in megagametophyte cells that arise post-germinatively were investigated. The accumulation of protease activities can be divided into two phases: the first phase correlated with degradation of storage proteins while the second phase was temporally associated with

Xu He; Allison R. Kermode

2003-01-01

335

Salt stress induced changes in germination, sugars, starch and enzyme of carbohydrate metabolism in Abelmoschus esculentus (L.) Moench seeds  

Microsoft Academic Search

During germination stage, the influence of NaCl on cumulative germination percentage, starch, total soluble sugar and phenol content in okra (Abelmoschus esculentus (L.) Moench, cultivar Marsaouia) seeds and growth seedlings components (cotyledons and embryonic axes) were studied. Seeds were sown in Petri dishes with varying concentrations of saline solutions (0, 20, 40, 60, 80 and 100 mM NaCl) at 25°C.

Besma Ben Dkhil; Mounir Denden

2010-01-01

336

Response of peroxidase and catalase to acid rain stress during seed germination of rice, wheat, and rape  

Microsoft Academic Search

Seed germination of plants with various acid-resistance display different responses to acid rain. To understand the reason\\u000a why such differences occur, the effects of simulated acid rain (pH 2.5–5.0) on the activities of peroxidase (POD) and catalase\\u000a (CAT) during seed germination of rice (O. sativa), wheat (T. aestivum), and rape (B. chinensis var. oleifera) were investigated. Results indicated that the

Lihong Wang; Xiaohua Huang; Qing Zhou

2008-01-01

337

Genes involved in ethylene and gibberellins metabolism are required for endosperm-limited germination of Sisymbrium officinale L. seeds  

Microsoft Academic Search

The rupture of the seed coat and that of the endosperm were found to be two sequential events in the germination of Sisymbrium officinale L. seeds, and radicle protrusion did not occur exactly in the micropylar area but in the neighboring zone. The germination\\u000a patterns were similar both in the presence of gibberellins (GA4+7) and in presence of ethrel. The

Raquel Iglesias-Fernández; Angel J. Matilla

2010-01-01

338

On the mechanisms of stimulation and inhibition of wheat seed germination by low-frequency magnetic field  

Microsoft Academic Search

Stimulation of wheat seed germination by brief exposure in a 50-Hz electromagnetic field (EMF) is shown to depend on the extent\\u000a of membrane stretching upon seed swelling in sucrose solutions. This again confirms the effect of low-frequency EMF on the\\u000a release of peripheral proteins from membranes. Prolonged exposure, on the contrary, decreases the germination rate and retards\\u000a seedling growth.

S. I. Aksyonov; T. Yu. Grunina; S. N. Goryachev

2007-01-01

339

Inhibition of Orobanche crenata seed germination and radicle growth by allelochemicals identified in cereals.  

PubMed

Orobanche crenata is a parasitic weed that causes severe yield losses in important grain and forage legume crops. Cereals have been reported to inhibit O. crenata parasitism when grown intercropped with susceptible legumes, but the responsible metabolites have not been identified. A number of metabolites have been reported in cereals that have allelopathic properties against weeds, pests, and pathogens. We tested the effect of several allelochemicals identified in cereals on O. crenata seed germination and radicle development. We found that 2-benzoxazolinone, its derivative 6-chloroacetyl-2-benzoxazolinone, and scopoletin significantly inhibited O. crenata seed germination. Benzoxazolinones, l-tryptophan, and coumalic acid caused the stronger inhibition of radicle growth. Also, other metabolites reduced radicle length, this inhibition being dose-dependent. Only scopoletin caused cell necrotic-like darkening in the young radicles. Prospects for their application to parasitic weed management are discussed. PMID:24044614

Fernández-Aparicio, Mónica; Cimmino, Alessio; Evidente, Antonio; Rubiales, Diego

2013-10-16

340

Effects of copper on germination and reserve mobilization in Vicia sativa L. seeds.  

PubMed

The effects of different copper concentrations on percentage germination, increase in fresh weight and radicle growth of Vicia sativa L. seeds were studied. Physiological studies showed that the germination rate was not affected up to a concentration of 5 × 10?³ M, but already at 10?³ M the copper stopped root elongation. Structural and ultrastructural observations of embryo and cotyledon reserve mobilization showed that inhibition of radicle growth at 10?³ M Cu concentration cannot be ascribed to nutrient shortage but probably to an effect of copper on radicle cell division and elongation. In seeds treated with 5 × 10?³ M CuBr?, the copper completely inhibited cotyledon protein mobilization, so that embryo protein mobilization supported normal growth of the radicle up to 30 h after imbibition. The particular protein content of adjacent cotyledon cells is also discussed. PMID:23649021

Muccifora, Simonetta; Bellani, Lorenza M

2013-08-01

341

Red fox ( Vulpes vulpes L.) favour seed dispersal, germination and seedling survival of Mediterranean Hackberry ( Celtis australis L.)  

NASA Astrophysics Data System (ADS)

Seeds of the Mediterranean Hackberry Celtis australis are often encountered in fox faeces. In order to evaluate the effect of gut transit on the size of seeds selected, the rates and speed of germination and on the survival of the seedlings, Mediterranean Hackberry seeds from fox faeces were germinated in a greenhouse. The results were compared with those of seeds taken from ripe, uneaten fruits. Fox-dispersed seeds were smaller and lighter than the control ones and had higher (74% vs. 57%) and more rapid germination (74.5 days vs. 99.2 days). Seedlings from fox-dispersed seeds showed significantly greater survival by the end of the study period (74.1% vs. 43.6%) than the control ones. Survival in seedlings from fox-dispersed seeds was related to germination date, late seedlings showing poorer survival. This relationship was not observed away in the control seedlings. Seed mass did not affect seedling survival. Seedling arising from fox-dispersed seeds grew faster than control ones. These results suggest that fox can play a relevant role as seed disperser of Mediterranean Hackberry.

Juan, Traba; Sagrario, Arrieta; Jesús, Herranz; Cristina, Clamagirand M.

2006-07-01

342

Differential response of antioxidative enzymes in embryonic axes and cotyledons of germinating lupine seeds  

Microsoft Academic Search

Germination of lupine (Lupinus luteus L.) seeds was accompanied by an increase in concentration of free radicals with g\\u000a \\u000a 1\\u000a and g\\u000a \\u000a 2\\u000a values of 2.0056 ± 0.0003 and 2.0033 ± 0.0005, respectively. The highest intensity of free radical signal was observed in\\u000a embryo axes immediately after radicle protruded through the seed coat. Hydrogen peroxide accumulated in embryonic axes and\\u000a cotyledons during imbibition before

Ma?gorzata Garnczarska; ?ukasz Wojtyla

2008-01-01

343

Posttranscriptional regulation of ?-amylase II-4 expression by gibberellin in germinating rice seeds  

Microsoft Academic Search

Hormonal regulation of expression of ?-amylase II-4 that lacks the gibberellin-response cis-element (GARE) in the promoter region of the gene was studied in germinating rice (Oryza sativa L.) seeds. Temporal and spatial expression of ?-amylase II-4 in the aleurone layer were essentially identical to those of ?-amylase I-1 whose gene contains GARE, although these were distinguishable in the embryo tissues

Yohei Nanjo; Satoru Asatsuma; Kimiko Itoh; Hidetaka Hori; Toshiaki Mitsui; Yukiko Fujisawa

2004-01-01

344

ALLELOPATHIC EFFECTS OF FIVE SELECTED WEED SPECIES ON SEED GERMINATION AND SEEDLING GROWTH OF CORN  

Microsoft Academic Search

Samad M. A., Rahman M. M., Hossain A. K. M. M., Rahman M. S. and Rahman S. M. 2008. Allelopathic Effects of Five Selected Weed Species on Seed Germination and Seedling Growth of Corn. J.Soil .Nature. 2(2): 13-18 An investigation was carried out in typical maize growing sandy loam soil at the Agronomy Laboratory. Bangladesh Agricultural University, Mymensingh during March

M. A. SAMAD; M. M. RAHMAN; M. S. RAHMAN; S. M. RAHMAN

345

Drought, salinity and heat differently affect seed germination of Pinus pinea  

Microsoft Academic Search

Drought, salinity and forest fires are adverse abiotic factors responsible for the failure of plant regeneration in the Mediterranean\\u000a regions. The objective of this study was to evaluate Pinus pinea seed germination in response to heat, osmotic and salinity stress. Separate experiments were conducted, using polyethylene\\u000a glycol (PEG) as an osmotic agent to reproduce drought stress, and sodium chloride (NaCl)

Maria Sidari; Carmelo Mallamaci; Adele Muscolo

2008-01-01

346

Germination response to fire-related factors of seeds from non-serotinous and serotinous cones  

Microsoft Academic Search

Pinus halepensis, a Mediterranean pine tree, is a partially serotinous species: individual trees of this species carry both non-serotinous\\u000a and serotinous cones. Serotinous cones open mainly after fire, whereas non-serotinous cones open in absence of fire. In this\\u000a study we addressed the question, whether or not this cone response is linked with the germination response of seeds to fires.\\u000a Two

S. Goubitz; M. J. A. Werger; G. Ne'eman

2002-01-01

347

Determination of amylase activity of crude extract from partially germinated mango seeds (Mangifera oraphila)  

Microsoft Academic Search

Amylase activity of crude extract from partially germinated mango seeds (Mangifera oraphila) was determined using Caraway-Somogyi iodine\\/potassium iodide (IKI) method. The effects of varied pH and temperature were also investigated. The amylase was extracted with 0.1 M acetate buffer (pH 4.2). Amylase activity of the crude extracts was measured by monitoring the amount of starch hydrolyzed by the crude extract

C. O. Edeogu

2009-01-01

348

Effect of salinity on seed germination, seedling growth, and physiological characteristics of Perilla frutescens  

Microsoft Academic Search

Salt stress is one of the major environmental factors limiting crop growth and yield. To understand the effect of salt stress on plant growth, we investigated the response of three perilla varieties (Suyin 1, Ziye 7, and Ziye 10) to NaC1 exposure at concentrations of 0, 50, 100, 150, 200, and 250 mM in terms of seed germination, seedling growth, root

Zhijun Zhang; Huizhen Li; Shaojun Qiao; Xin Zhang; Peipei Liu; Xiliang Liu

2011-01-01

349

Effect of salinity on seed germination, seedling growth, and physiological characteristics of Perilla frutescens  

Microsoft Academic Search

Salt stress is one of the major environmental factors limiting crop growth and yield. To understand the effect of salt stress on plant growth, we investigated the response of three perilla varieties (Suyin 1, Ziye 7, and Ziye 10) to NaC1 exposure at concentrations of 0, 50, 100, 150, 200, and 250 mM in terms of seed germination, seedling growth, root

Zhijun Zhang; Huizhen Li; Shaojun Qiao; Xin Zhang; Peipei Liu; Xiliang Liu

2012-01-01

350

Xyloglucan endotransglycosylases (XETs) from germinating nasturtium ( Tropaeolum majus) seeds: Isolation and characterization of the major form  

Microsoft Academic Search

Five forms of xyloglucan endotransglycosylase\\/hydrolase (XTH) differing in their isoelectric points (pI) were detected in crude extracts from germinating nasturtium seeds. Without further fractionation, all five forms behaved as typical endotransglycosylases since they exhibited only transglycosylating (XET) activity and no xyloglucan-hydrolysing (XEH) activity. They all were glycoproteins with identical molecular mass, and deglycosylation led to a decrease in molecular mass

Eva Stratilová; Fairouz Ait-Mohand; Pavel ?ehulka; So?a Garajová; Dana Flodrová; Helena ?ehulková; Vladimír Farkaš

2010-01-01

351

Application of response surface methodology for extraction optimization of germinant pumpkin seeds protein  

Microsoft Academic Search

Response surface methodology was employed to study the effect of liquid:solid ratio, NaCl concentration and reaction time on the production of protein from germinant pumpkin seeds. Regression analysis was performed on the data obtained. The most relevant variable was liquid:solid ratio. The coefficient determination (R2) was good for the second-order model. A liquid:solid ratio of 30.2: 1 (v\\/w), a NaCl

Li Quanhong; Fu Caili

2005-01-01

352

Detection of DNA methylation changes during seed germination in rapeseed ( Brassica napus )  

Microsoft Academic Search

DNA methylation is known to play a crucial role in regulating plant development and organ or tissue differentiation. In this\\u000a study, we assessed the extent and pattern of cytosine methylation during rapeseed (Brassica napus L.) seed germination, and compared the methylation level of various tissues in seedling, using the techniques of methylation-sensitive\\u000a amplified polymorphism (MSAP) and HPLC separation and quantification

Guangyuan Lu; Xiaoming Wu; Biyun Chen; Guizhen Gao; Kun Xu; Xiangzhi Li

2006-01-01

353

Effect of Magnaporthe grisea on Seed Germination, Yield and Quality of Wheat  

Microsoft Academic Search

The effect of wheat blast, caused by Magnaporthe grisea (Pyricularia grisea), on seed germination, yield loss and grain quality was evaluated during the growing season of 2005 in wheat cultivars BRS208\\u000a and CD104 in Sao Paulo State, Brazil. Each field was divided in an imaginary diagonal line crossing the center and then five\\u000a areas of one m2$ each separated 10

A. S. Urashima; C. R. F. Grosso; A. Stabili; E. G. Freitas; C. P. Silva; D. C. S. Netto; I. Franco; J. H. Merola Bottan

354

Factors affecting seed germination of Eleocharis cellulosa and Rhyncospora tracyi from the northern Everglades  

Microsoft Academic Search

The re-establishment of native plant communities, in particular the re-creation of ridge (sawgrass dominated; Cladium jamaicense) and slough (Eleocharis spp. and Nymphaea odorata) habitat, is a significant component of Everglades restoration. Two wetland species indicative of pristine slough habitats\\u000a are Eleocharis cellulosa and Rhynchospora tracyi. This study conducted controlled experiments to examine three factors affecting seed germination of native slough

Jennifer A. Leeds; Susan Newman; Stephen M. Smith

2006-01-01

355

Lipase activity and antioxidant capacity in coffee (Coffea arabica L.) seeds during germination.  

PubMed

In this paper, lipase activity was characterized in coffee (Coffea arabica L.) seeds to determine its involvement in lipid degradation during germination. The lipase activity, evaluated by a colorimetric method, was already present before imbibition of seeds and was further induced during the germination process. The activity showed a biphasic behaviour, which was similar in seeds either with or without endocarp (parchment), even though the phenomenon showed a delay in the former. The enzymatic activity was inhibited by tetrahydrolipstatin (THL), a selective and irreversible inhibitor of lipases, and by a polyclonal antibody raised against purified alkaline lipase from castor bean. The immunochemical analysis evidenced a protein of ca. 60 kDa, cross-reacting with an anti-lipase antibody, in coffee samples obtained from seeds of both types. Gas chromatographic analyses of free fatty acid (FFA) content confirmed the differences shown in the lipolytic activity of the samples with or without parchment, since FFA levels increased more rapidly in samples without parchment. Finally, the analyses of the antioxidant capacity showed that the presence of parchment was crucial for lowering the oxidation of the lipophylic fraction, being the seeds with parchment less prone to oxidation processes. PMID:24576760

Patui, Sonia; Clincon, Luisa; Peresson, Carlo; Zancani, Marco; Conte, Lanfranco; Del Terra, Lorenzo; Navarini, Luciano; Vianello, Angelo; Braidot, Enrico

2014-04-01

356

Vitamin E Is Essential for Seed Longevity and for Preventing Lipid Peroxidation during Germination  

PubMed Central

Tocopherols (vitamin E) are lipophilic antioxidants synthesized by all plants and are particularly abundant in seeds. Despite cloning of the complete suite of tocopherol biosynthetic enzymes and successful engineering of the tocopherol content and composition of Arabidopsis thaliana leaves and seeds, the functions of tocopherols in plants have remained elusive. To address this issue, we have isolated and characterized two VITAMIN E loci (VTE1 and VTE2) in Arabidopsis that when mutated result in tocopherol deficiency in all tissues. vte1 disrupts tocopherol cyclase activity and accumulates a redox-active biosynthetic intermediate, whereas vte2 disrupts homogentisate phytyl transferase activity and does not accumulate pathway intermediates. Mutations at either locus cause significantly reduced seed longevity compared with the wild type, indicating a critical role for tocopherols in maintaining viability during quiescence. However, only vte2 mutants exhibited severe seedling growth defects during germination and contained levels of lipid hydroperoxides and hydroxy fatty acids elevated up to 4- and 100-fold, respectively, relative to the wild type. These data demonstrate that a primary function of tocopherols in plants is to limit nonenzymatic lipid oxidation during seed storage, germination, and early seedling development. The vte mutant phenotypes also explain the strong selection for retention of tocopherol biosynthesis during the evolution of seed-bearing plants. PMID:15155886

Sattler, Scott E.; Gilliland, Laura U.; Magallanes-Lundback, Maria; Pollard, Mike; DellaPenna, Dean

2004-01-01

357

Vitamin E is essential for seed longevity and for preventing lipid peroxidation during germination.  

PubMed

Tocopherols (vitamin E) are lipophilic antioxidants synthesized by all plants and are particularly abundant in seeds. Despite cloning of the complete suite of tocopherol biosynthetic enzymes and successful engineering of the tocopherol content and composition of Arabidopsis thaliana leaves and seeds, the functions of tocopherols in plants have remained elusive. To address this issue, we have isolated and characterized two VITAMIN E loci (VTE1 and VTE2) in Arabidopsis that when mutated result in tocopherol deficiency in all tissues. vte1 disrupts tocopherol cyclase activity and accumulates a redox-active biosynthetic intermediate, whereas vte2 disrupts homogentisate phytyl transferase activity and does not accumulate pathway intermediates. Mutations at either locus cause significantly reduced seed longevity compared with the wild type, indicating a critical role for tocopherols in maintaining viability during quiescence. However, only vte2 mutants exhibited severe seedling growth defects during germination and contained levels of lipid hydroperoxides and hydroxy fatty acids elevated up to 4- and 100-fold, respectively, relative to the wild type. These data demonstrate that a primary function of tocopherols in plants is to limit nonenzymatic lipid oxidation during seed storage, germination, and early seedling development. The vte mutant phenotypes also explain the strong selection for retention of tocopherol biosynthesis during the evolution of seed-bearing plants. PMID:15155886

Sattler, Scott E; Gilliland, Laura U; Magallanes-Lundback, Maria; Pollard, Mike; DellaPenna, Dean

2004-06-01

358

Environmental effects of nanosilver: impact on castor seed germination, seedling growth, and plant physiology.  

PubMed

Increasing use of nanoparticles in daily products is of great concern today, especially when their positive and negative impact on environment is not known. Hence, in current research, we have studied the impact of silver nanoparticle (AgNPs) and silver nitrate (AgNO3) application on seed germination, root, and shoot length of castor bean, Ricinus communis L. plant. Silver nanoparticles had no significant effects on seedling growth even at higher concentration of 4,000 mg L(-1), while the silver in bulk form as AgNO3 applied on the castor bean seeds inhibited the seed germination. Silver uptake in seedlings of the castor seeds on treatment with both the forms of silver was confirmed through atomic absorption spectroscopy studies. The silver nanoparticle and silver nitrate application to castor seeds also caused an enhanced enzymatic activity of ROS enzymes and phenolic content in castor seedlings. High-performance liquid chromatography analysis of individual phenols indicated enhanced content of parahydroxy benzoic acid. These kinds of studies are of great interest in order to unveil the movement and accumulation of nanoparticles in plant tissues for assessing future applications in the field or laboratory. PMID:23702569

Yasur, Jyothsna; Rani, Pathipati Usha

2013-12-01

359

Mobilization of reserve proteins and activities of cysteine peptidases during germinative and post-germinative events of cowpea seeds.  

PubMed

Cysteine peptidases are the best characterized peptidases among those involved with storage protein mobilization during seed germination. In the present work we show two major groups of cysteine peptidase activities, one of higher (55 to 97 kDa) and other with lower (15 to 20 kDa) molecular masses which are temporally activated after 24 and 48 HAI, respectively, in germinating cowpeas. The former group is found both in protein bodies and in cytoplasmic fraction, while the latter is mostly present outside protein bodies. A third cysteine peptidase activity of ~37 kDa was specifically active at quiescent cotyledons and at 12 and 60 hours after imbibition (HAI). Main peptidase activities of albumin fractions were synchronizedly detected with radicle emergence at 36 HAI. Major vicilin mobilization was more pronounced from 60 HAI onwards and steadily increased until 144 HAI, when low levels of the smallest vicilin subunit were present. Cysteine peptidases were susceptible to iodoacetamide, E-64, iodoacetic acid, pCMB and ?-mercaptoethanol, except for the ~37 kDa peptidase, which was not affected by any of the inhibitors. By a two-dimensional native/SDS-PAGE combination it was observed an apparent linear arrangement of protein breakdown products as well as of peptidase activity spots. The finding may indicate a complex set of sequential proteolytic events where peptidases induce or activate new peptidases, which may act upon different aggregates or zymogens, and these hydrolysis products appear in a line of constant decreasing Rf x Mr ratio. PMID:22670671

de Oliveira, Lucilene Ollivier; Retamal, Cláudio Andrés; da Cunha, Maura; Oliveira, Antônia Elenir Amâncio; Pinto, Márcio dos Santos Teixeira; Fernandes, Kátia Valevski Sales

2012-12-01

360

Reversal of the inhibitory effect of light and high temperature on germination of Phacelia tanacetifolia seeds by melatonin.  

PubMed

Possible role of melatonin in the germination of negatively photoblastic and thermosensitive seeds of Phacelia tanacetifolia Benth was studied. Final germination percentage (FGP) was determined in the presence or absence of light at various temperatures, ranging from 0 to 40°C. The highest FGP was determined as 48.7% and 92% at temperature of 15°C in the presence and absence of light, respectively. Seeds were primed with 1% KNO(3) containing various concentrations (0.3, 1, 6, 12, 30, 60, or 90 ?M) of melatonin for 2 days at 15°C in darkness. Primed seeds were germinated at an inhibitory temperature of 30°C, and results were compared to those occurring at the optimum temperature of 15°C under both light and no light conditions. Melatonin incorporated into priming medium significantly reversed the inhibitory effects of light and high temperature. Germination was elevated from 2.5% to 52% of FGP for seeds primed in the presence of 6 ?M melatonin in darkness at 30°C, while 1 ?M melatonin had the highest FGP (21.0%) in the presence of light at 30°C. The highest FGP (47.5%) was obtained from seeds primed in the presence of 0.3 ?M melatonin under the light condition at 15°C, while untreated seeds had 1.5% of FGP. The fastest seed germination was determined from seeds primed in the presence of 0.3 ?M melatonin (G(50) = 0.56 days) at 15°C in darkness. The possible roles of melatonin in promoting germination parameters of photo- and thermosensitive seed germination are discussed. PMID:22225610

Tiryaki, Iskender; Keles, Huseyin

2012-04-01

361

[Allelopathic effects of Artemisia frigida on three Poaceae plants seed germination and seedling growth].  

PubMed

Aqueous extracts of Artemisia frigida leaf and stem and soils beneath A. frigida were used to test their allelopathic effects on the seed germination and seedling growth of three Poaceae plants (Leymus chinensis, Stipa krylovii, and Cleistogenes squarrosa) on Leymus chinensis grassland. The aqueous extracts of A. frigida leaf and stem decreased the seed germination index of test plants and prolonged their seed germination time, and inhibited the shoot growth of the three plants and the root growth of S. krylovii. The aqueous extracts at concentration > or = 0.075 g x ml(-1) presented a strong inhibition on the root growth of L. chinensis, while those at concentration < or = 0.05 g x ml(-1) had less effects. For the root growth of C. squarrosa, the aqueous extracts showed a "low-promotion and high-inhibition effect". Under the effects of A. frigida soil, the seedling growth of test plants was inhibited. The sensitivity of test plants to the allelopathic effects of A. frigida was in the order of S. krylovii > L. chinense > C. squarrosa, with a higher sensitivity of root growth than shoot growth. PMID:20879526

Li, Xue-feng; Wang, Jian; Xu, Wen-bo; Wang, Kun

2010-07-01

362

Ecotoxicological effects of polycyclic musks and cadmium on seed germination and seedling growth of wheat ( Triticum aestivum)  

Microsoft Academic Search

Single and joint toxic effects of polycyclic musks including 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethylcyclopenta[g]-2-benzopyran (HHCB) and 7-acetyl-1,1,3,4,4,6-hexamethyl-1,2,3,4-tetrahydronapthalene (AHTN) and cadmium (Cd) on seed germination and seedling growth of wheat (Triticum aestivum) were investigated. The results showed that the toxicity sequence of HHCB toxic to wheat seed germination and seedling growth was similar to that of AHTN, that is, germination rate > shoot elongation >

Cuihong Chen; Qixing Zhou; Yanyu Bao; Yaning Li; Ping Wang

2010-01-01

363

In vivo monoubiquitination of anaplerotic phosphoenolpyruvate carboxylase occurs at Lys624 in germinating sorghum seeds  

PubMed Central

Phosphoenolpyruvate carboxylase (PEPC; EC 4.1.1.31) is an important cytosolic regulatory enzyme that plays a pivotal role in numerous physiological processes in plants, including seed development and germination. Previous studies demonstrated the occurrence of immunoreactive PEPC polypeptides of ~110kDa and 107kDa (p110 and p107, respectively) on immunoblots of clarified extracts of germinating sorghum (Sorghum bicolor) seeds. In order to establish the biochemical basis for this observation, a 460kDa PEPC heterotetramer composed of an equivalent ratio of p110 and p107 subunits was purified to near homogeneity from the germinated seeds. Mass spectrometry established that p110 and p107 are both encoded by the same plant-type PEPC gene (CP21), but that p107 was in vivo monoubiquitinated at Lys624 to form p110. This residue is absolutely conserved in vascular plant PEPCs and is proximal to a PEP-binding/catalytic domain. Anti-ubiquitin IgG immunodetected p110 but not p107, whereas incubation with a deubiquitinating enzyme (USP-2 core) efficiently converted p110 into p107, while relieving the enzyme’s feedback inhibition by l-malate. Partial PEPC monoubiquitination was also detected during sorghum seed development. It is apparent that monoubiquitination at Lys624 is opposed to phosphorylation at Ser7 in terms of regulating the catalytic activity of sorghum seed PEPC. PEPC monoubiquitination is hypothesized to fine-tune anaplerotic carbon flux according to the cell’s immediate physiological requirements for tricarboxylic acid cycle intermediates needed in support of biosynthesis and carbon–nitrogen interactions. PMID:24288181

Echevarria, Cristina

2014-01-01

364

CAMBIOS EN BIOMASA, VIABILIDAD Y GERMINACIÓN DE SEMILLAS EN DESARROLLO DE TRIGO BIOMASS, VIABILITY AND GERMINATION CHANGES IN DEVELOPING WHEAT SEEDS  

Microsoft Academic Search

In some cereal breeding programs, duration of the selection cycles can be reduced using immature seeds with germination values acceptable for the purposes of plant breeders. A study was con- ducted at Chapingo, State of México, to evaluate how genotype and seed position on the spike affect the accumulation of biomass, viability and germination of developing wheat seeds ( Triticum

Rafael Mora-Aguilar; Rodolfo Fernández-Vidal; Leopoldo E. Mendoza-Onofre

2000-01-01

365

Gibberellic acid (GA3) enhance seed water uptake, germination and early seedling growth in sugar beet under salt stress.  

PubMed

The study was carried out to assess whether water uptake could be improved in sugar beet seeds and salt tolerance at the germination and early seedling stage by soaking the seeds for 10 h in distilled water (control), 100, 150 and 200 mg L(-1) GA3. Electrical Conductivity (EC) values of the NaCl solution were 0.0 (control), 4.7, 9.4 and 14.1 dS n(-1) NaCl. Priming increased the final germination percentage and the germination rate (1/t 50, where t 50 is the time to 50% of germination) under saline condition. Water uptake of primed seeds also increased significantly with increasing concentration of GA3 as compared to control. Priming also alleviated the adverse effect of salt stress on sugar beet in terms of roots and shoots lengths and fresh weights of plants, roots and shoots. PMID:19069553

Jamil, Muhammad; Rha, Eui Shik

2007-02-15

366

Coordinated changes in storage proteins during development and germination of elite seeds of Pongamia pinnata, a versatile biodiesel legume  

PubMed Central

Background and aims The oleaginous legume Pongamia pinnata is a rapidly growing and economically important tree. The seeds are used increasingly as feedstock for biodiesel production, with the protein-rich residue providing valuable supplement to farm animal diets. However, little is known about seed development and the characteristics of germination. We therefore studied morphological, protein and ultrastructural changes during seed maturation and germination using seeds from a tree selected for superior morphological and reproductive characters (candidate plus tree). Methodology Phenology, sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS–PAGE), and scanning and transmission electron microscopy were used to investigate seed development from 90 to 350 days after flowering (DAF), and germination and seedling development from 0 to 45 days after the start of imbibition (DAI) (Stages 0–VII). Principal results Seven distinct developmental stages were identified during seed development. Fresh weight, length, breadth and thickness increased from Stage I (90 DAF) to V (270 DAF) and decreased at Stages VI (315 DAF) and VII (350 DAF), when the seeds were fully ripe. Marked changes in total soluble protein content and SDS–PAGE profile were observed in vegetative and reproductive tissues and in the cotyledons of germinating seedlings. Polypeptide fragments of 150–14 kDa were observed during seed maturation and germination. In SDS–PAGE the expression of three main polypeptide bands (50, 18 and 14 kDa) increased from Stage I to Stage V and then almost became the same until Stage VII during seed maturation. During germination the expression of 50 kDa polypeptide decreased and that of 18 and 14 kDa increased from Stage 0 (ungerminated seed) to Stage VI (30 DAI), respectively; however, all three polypeptides (50, 18 and 14 kDa) completely disappeared at Stage VII (45 DAI). Ultrastructural changes during four stages of seed maturation (early immature, 90–135 DAF; late immature, 180–225 DAF; early mature, 225–270 DAF; and late mature, 315–350 DAF) and three stages of germination and seedling development (early 10 DAI to late 45 DAI) localized marked gradients in protein storage reserves. Conclusions Increasing the knowledge base for P. pinnata, especially for its seeds, is an essential prerequisite for rapid and successful exploitation of this promising energy and animal feed crop. Our findings contribute to this by establishing key developmental features of the seeds as they form and germinate. PMID:22476496

Kesari, Vigya; Rangan, Latha

2011-01-01

367

Analysis of Gene Expression during Brassica Seed Germination Using a Cross- Species Microarray Platform  

E-print Network

We have developed an approach to facilitate the use of model organism microarrays in related, nonmodel organisms. We demonstrate the method by using Arabidopsis oligonucleotide microarrays to analyze gene expression in Brassica. Probes with low hybridization signals to Brassica genomic DNA were excluded from the transcriptional analysis of an Arabidopsis microarray at the software level, forming a virtual Brassica microarray. We then performed an experiment on transcriptional responses during seed germination in Brassica using 17 886 homologous probesets of the virtual array where Brassica mRNA hybridization was detected. We subjected seed to hydration or priming (a step to improve germination vigor) and subsequent heating and drying treatments (steps to prolong shelf life of dried seed). Exploration of the microarray results indicated two likely expression patterns shared by many genes. One class of transcripts was strongly, globally, and irreversibly downregulated by priming, while other transcripts were induced, but often reversibly. Legacy seed-storage protein messages were in the fi rst class, and many protein synthesis components and some resource mobilization enzymes were in the second. We were able to validate our results by confi rming transcriptional responses using reverse transcription polymerase chain reaction (RT–PCR).

Ge Ome; Matthew E. Hudson; Tonko Bruggink; H. Chang; Wenjin Yu; Bin Han; Xun Wang; Van Der Toorn; Tong Zhu; T. Zhu

2007-01-01

368

Growth stimulation of radish sprouts using discharge plasmas  

Microsoft Academic Search

We have investigated growth stimulation of radish sprouts using nonthermal atmospheric pressure He discharge plasmas and low pressure O2 RF discharge plasmas. Seeds of radish sprouts were irradiated by one of these plasmas. After 7 days cultivation, the average length of sprouts with irradiation was 15-60% longer than those without irradiation. Reactive oxygen species may be involved in the growth

Satoshi Kitazaki; Daisuke Yamashita; H. Matsuzaki; G. Uchida; K. Koga; M. Shiratani; N. Hayashi

2010-01-01

369

Long-term persistence of crop alleles in weedy populations of wild radish (Raphanus raphanistrum)  

E-print Network

Long-term persistence of crop alleles in weedy populations of wild radish (Raphanus raphanistrum) A­wild hybridization, gene flow, introgression, rapid evolution, transgene escape, weed evolution, wild radish-seeding, hybrid populations of Raphanus raphani- strum · Raphanus sativus (radish) in Michigan, USA, over a decade

Snow, Allison A.

370

The effect of pre-emergent herbicides on germination and early growth of broadleaved species used for direct seeding  

Microsoft Academic Search

Summary Weed control is essential for successful new woodland creation by direct seeding, particularly in the first year after germination. Currently, herbicides probably offer the most practical way of achieving this in UK conditions, although successful direct seeding offers the potential for reductions in total overall herbicide use compared with conventional establishment using transplants. There is a need to identify

IAN WILLOUGHBY; DAVID CLAY; FIONA DIXON

2003-01-01

371

In vitro germination, protocorm formation and plantlet development of mature versus immature seeds from several Ophrys species (Orchidaceae)  

Microsoft Academic Search

We investigated the effect of genotype, seed maturity and culture medium on the in vitro germination and development of protocorms and plantlets from seeds of 13 different Ophrys species ( O. apifera, O. attica, O. cornuta, O. delfinensis, O. ferrum-equinum, O. lutea, O. mammosa, O. speculum, O. spruneri, O. umbilicata, O. argolica, O. irricolor and O. tenthredinifera) collected in Greece,

C. K. Kitsaki; S. Zygouraki; M. Ziobora; S. Kintzios

2004-01-01

372

Variation within species and inter-species comparison of seed dormancy and germination of four annual Lamium species  

Microsoft Academic Search

In an ecological context, knowledge of intra-species variation in dormancy and germination is necessary both for practical and theoretical reasons. We used four or five seed batches (replicates) of four closely related annuals co-occurring in arable fields in Sweden: Lamium amplexicaule, L. confertum, L. hybridum and L. purpureum. Seeds used for experiments stemmed from plants cultivated on two sites, each

Laila M. Karlsson; Per Milberg

2008-01-01

373

Changes in the Water Content and Germination Rate During Seed Desiccation and Their Inter-Specifirc Differences among Zizania Species  

Microsoft Academic Search

Wild rice (Zizania palustris) is a newly cultivated crop that is known for its quality com- pounds of human health benefits. Zizania seeds are extremely sensitive to drought during the maturing and storage period. This study was conducted to examine the effect of seed water content on germination in three Zizania species, Z. aquatica, Z. Iat~folia and Z. palustris that

Il-Doo JIN; Song Joong YUN; Yuko MATSUISHI

374

Effect of Liquid Nitrogen Storage on Seed Germination of 51 Tree Species  

E-print Network

Two liquid nitrogen storage experiments were performed on 51 tree species. In experiment 1, seeds of 9 western tree species were placed in a liquid nitrogen tank for 3 time periods: 24 hours, 4 weeks, and 222 days. A corresponding control sample accompanied each treatment. For three species, Calocedrus decurrens, Pinus jefferyi, and Pinus contorta, the germination percent was not significantly different from the controls in any of the liquid nitrogen treatments. Exposure to 24 hours of liquid nitrogen did not affect the germination percent for any of the 9 species compared to their controls. Two species, Abies x shastensis and Picea engelmannii, exhibited a significant negative response to 4 weeks exposure to liquid nitrogen. Four species Abies amabilis, Abies concolor, Pinus monticola, and Pseudotsuga menziesii, exhibited a significant positive response to the 222-day exposure to liquid nitrogen when compared with Control D. Experiment 2 examined the germination response to liquid nitrogen storage after a 24 hour exposure for 42 tree species. The germination percent for nine of the 42 species, Acer rubra, Celtis occidentalis, Lonicera tartarica, Malus prunifolia, Physiocarpus opulifiolius, Pinus banksiana, Pinus clausa, Pinus nigra, and Pinus rigida, was significantly affected by 24 hours exposure to liquid nitrogen. Liquid nitrogen exposure had a negative affect on germination for 7 species and a positive effect for 2 species, Pinus nigra, and Pinus rigida. Only 8 species had enough data to calculate the correlation coefficient between moisture content and germination after exposure to liquid nitrogen. Correlations were significant for 4 species. Two species, Abies fraseri and Liriodendron tulipfera had negative correlations; two species, Pinus ponderosa and Pinus taeda had positive correlations.

unknown authors

375

Analysis of directional root growth patterns from corn and soybean seeds germinated in space  

NASA Astrophysics Data System (ADS)

The JOSE (JASON Outreach Seed Experiment) payload was the first plant experiment conducted on the International Space Station (ISS). It consisted of having an on-orbit watering of eight transparent seed pouches each of which contained 6 individual seeds of either soybean (Glycine max cv McCall) or corn ( Zea mays ). The seeds were glued to a germination paper substrate using a 1.2% guar glue solution. The payload was launched on the Orbiter Endeavour (STS-97; ISS Flight 4A) on 11/30/00 and transferred to the ISS on 12/8/00. The eight seed pouches were each watered with 12 mL of distilled water on 1/5/01. Two pouches containing corn plus two pouches containing soybean seeds were maintained in the light after watering. Two additional seed pouches of each species were maintained in the dark after watering. Digital photography was used to document the growth of the germinating seedlings in space. The images were down-linked to a world wide web site for dissemination to students. "Within" species differences (between the light and dark grown seedlings) as well as "between" species differences (comparing corn and soybean) were observed. By day 4 (post-imbibition) there was a clear phototropic effect in the light-grown corn seedlings, each, possessing a green shoot which grew upward towards the light source. In contrast, the dark-grown corn shoots were neither green (since chlorophyll synthesis had not been induced by light) nor were they growing in a uniform direction. For day 4 soybean seedlings, the only difference evident between those germinated under the light vs dark conditions was a slight greening up of the seeds maintained in the presence of light. For both the corn and soybean seedlings, roots grew in a random fashion, with some moving in an upward direction and others progressing downward, reflecting the lack of a gravitropic response which is the primary (earth-based) mechanism controlling the direction of root growth. By day 7 the initial 12 mL of water added to each pouch was greatly diminished, although noticeably less so in the soybean pouches. This was presumably due to the faster and overall greater growth exhibited by the corn seedlings, which resulted in a more rapid utilization of the available water. There was also a more pronounced greening-up of the light-exposed soybean seedlings than was evident at day 4, with both the cotylendons and hypocotyl regions showing signs of chlorophyll synthesis. This work was supported under NASA Contract NAS10-002001.

Levine, H.; Tynes, G.; Norwood, K.

376

A genetic locus and gene expression patterns associated with the priming effect on lettuce seed germination at elevated temperatures.  

PubMed

Seeds of most cultivated varieties of lettuce (Lactuca sativa L.) fail to germinate at warm temperatures (i.e., above 25-30 degrees C). Seed priming (controlled hydration followed by drying) alleviates this thermoinhibition by increasing the maximum germination temperature. We conducted a quantitative trait locus (QTL) analysis of seed germination responses to priming using a recombinant inbred line (RIL) population derived from a cross between L. sativa cv. Salinas and L. serriola accession UC96US23. Priming significantly increased the maximum germination temperature of the RIL population, and a single major QTL was responsible for 47% of the phenotypic variation due to priming. This QTL collocated with Htg6.1, a major QTL from UC96US23 associated with high temperature germination capacity. Seeds of three near-isogenic lines (NILs) carrying an Htg6.1 introgression from UC96US23 in a Salinas genetic background exhibited synergistic increases in maximum germination temperature in response to priming. LsNCED4, a gene encoding a key enzyme (9-cis-epoxycarotinoid dioxygenase) in the abscisic acid biosynthetic pathway, maps precisely with Htg6.1. Expression of LsNCED4 after imbibition for 24 h at high temperature was greater in non-primed seeds of Salinas, of a second cultivar (Titan) and of NILs containing Htg6.1 compared to primed seeds of the same genotypes. In contrast, expression of genes encoding regulated enzymes in the gibberellin and ethylene biosynthetic pathways (LsGA3ox1 and LsACS1, respectively) was enhanced by priming and suppressed by imbibition at elevated temperatures. Developmental and temperature regulation of hormonal biosynthetic pathways is associated with seed priming effects on germination temperature sensitivity. PMID:20047028

Schwember, Andrés R; Bradford, Kent J

2010-05-01

377

Irrigation and fertilization effects on seed number, size, germination and seedling growth: implications for desert shrub establishment.  

PubMed

Plants with limited resources adjust partitioning among growth, survival, and reproduction. We tested the effects of water and nutrient amendments on seed production, size, and quality in Sarcobatus vermiculatus (greasewood) to assess the magnitude and importance of changes in reproductive partitioning. In addition, we assessed interactions among the environment of seed-producing plants (adult plant scale), seed size, and seedling microenvironment (seedling scale) on successful seedling establishment. Interactions of these factors determine the scale of resource heterogeneity that affects seedling establishment in deserts. Both total number of seeds produced per plant and seed quality (weight and germination) increased significantly in the enriched treatment in a 3-year field experiment. Seedling length 3 days after germination and seed N concentration, other measures of seed quality, were higher for seed from both irrigated and enriched plants than for seed from control plants. Field S. vermiculatus seed production and quality can be substantially increased with irrigation and nutrient enrichment at the adult plant scale and this allows management of seed availability for restoration. However, based on a greenhouse study, seedling environment, not the environment of the seed-producing plant or seed size, was the most important factor affecting seedling germination, survival, and growth. Thus it appears that production of more seed may be more important than improved seed quality, because higher quality seed did not compensate for a low-resource seedling environment. For both natural establishment and restoration this suggests that heterogeneity at the scale of seedling microsites, perhaps combined with fertilization of adult shrubs (or multi-plant patches), would produce the greatest benefit for establishing seedlings in the field. PMID:18481096

Breen, A N; Richards, J H

2008-08-01

378

Analysis of tyrosine phosphorylation and phosphotyrosine-binding proteins in germinating seeds from Scots pine.  

PubMed

Protein tyrosine phosphorylation in angiosperms has been implicated in various physiological processes, including seed development and germination. In conifers, the role of tyrosine phosphorylation and the mechanisms of its regulation are yet to be investigated. In this study, we examined the profile of protein tyrosine phosphorylation in Scots pine seeds at different stages of germination. We detected extensive protein tyrosine phosphorylation in extracts from Scots pine (Pinus sylvestris L.) dormant seeds. In addition, the pattern of tyrosine phosphorylation was found to change significantly during seed germination, especially at earlier stages of post-imbibition which coincides with the initiation of cell division, and during the period of intensive elongation of hypocotyls. To better understand the molecular mechanisms of phosphotyrosine signaling, we employed affinity purification and mass spectrometry for the identification of pTyr-binding proteins from the extracts of Scots pine seedlings. Using this approach, we purified two proteins of 10 and 43 kDa, which interacted specifically with pTyr-Sepharose and were identified by mass spectrometry as P. sylvestris defensin 1 (PsDef1) and aldose 1-epimerase (EC:5.1.3.3), respectively. Additionally, we demonstrated that both endogenous and recombinant PsDef1 specifically interact with pTyr-Sepharose, but not Tyr-beads. As the affinity purification approach did not reveal the presence of proteins with known pTyr binding domains (SH2, PTB and C2), we suggest that plants may have evolved a different mode of pTyr recognition, which yet remains to be uncovered. PMID:23542181

Kovaleva, Valentina; Cramer, Rainer; Krynytskyy, Hryhoriy; Gout, Ivan; Gout, Roman

2013-06-01

379

A rice F-box gene, OsFbx352, is involved in glucose-delayed seed germination in rice.  

PubMed

F-box proteins play diverse roles in regulating numerous physiological processes in plants. This study isolated a gene (OsFbx352) from rice encoding an F-box domain protein and characterized its role in seed germination. Expression of OsFbx352 was upregulated by abscisic acid (ABA). The transcripts of OsFbx352 were increased upon imbibition of rice seeds and the increase was markedly suppressed by glucose. Germination of seeds with overexpression of OsFbx352 was less suppressed by glucose than that of wild-type seeds, while glucose had greater inhibition for germination of seeds with knockdown of OsFbx352 by RNA interference (RNAi) than that of wild-type seeds. The differential response of germination of the transgenic and wild-type seeds to glucose may be accounted for by differences in ABA content among overexpressing, RNAi, and wild-type seeds such that overexpression of OsFbx352 and knockdown of OsFbx352 led to lower and higher ABA contents, respectively, than that of wild-type seeds in the presence of glucose. Overexpression of OsFbx352 led to a reduction in expression of genes responsible for ABA synthesis (OsNced2, OsNced3) and an increase in expression of genes encoding ABA catabolism (OsAba-ox2, OsAba-ox3) in the presence of glucose. These findings indicate that OsFbx352 plays a regulatory role in the regulation of glucose-induced suppression of seed germination by targeting ABA metabolism. PMID:22859682

Song, Shiyong; Dai, Xiaoyan; Zhang, Wen-Hao

2012-09-01

380

Prior hydration of Brassica tournefortii seeds reduces the stimulatory effect of karrikinolide on germination and increases seed sensitivity to abscisic acid  

PubMed Central

Background and Aims The smoke-derived compound karrikinolide (KAR1) shows significant potential as a trigger for the synchronous germination of seeds in a variety of plant-management contexts, from weed seeds in paddocks, to native seeds when restoring degraded lands. Understanding how KAR1 interacts with seed physiology is a necessary precursor to the development of the compound as an efficient and effective management tool. This study tested the ability of KAR1 to stimulate germination of seeds of the global agronomic weed Brassica tournefortii, at different hydration states, to gain insight into how the timing of KAR1 applications in the field should be managed relative to rain events. Methods Seeds of B. tournefortii were brought to five different hydration states [equilibrated at 15 % relative humidity (RH), 47 % RH, 96 % RH, fully imbibed, or re-dried to 15 % RH following maximum imbibition] then exposed to 1 nm or 1 µm KAR1 for one of five durations (3 min, 1 h, 24 h, 14 d or no exposure). Key Results Dry seeds with no history of imbibition were the most sensitive to KAR1; sensitivity was lower in seeds that were fully imbibed or fully imbibed then re-dried. In addition, reduced sensitivity to KAR1 was associated with an increased sensitivity to exogenously applied abscisic acid (ABA). Conclusions Seed water content and history of imbibition were found to significantly influence whether seeds germinate in response to KAR1. To optimize the germination response of seeds, KAR1 should be applied to dry seeds, when sensitivity to ABA is minimized. PMID:20348089

Long, Rowena L.; Williams, Kimberlyn; Griffiths, Erin M.; Flematti, Gavin R.; Merritt, David J.; Stevens, Jason C.; Turner, Shane R.; Powles, Stephen B.; Dixon, Kingsley W.

2010-01-01

381

Analysis of Proteome Profile in Germinating Soybean Seed, and Its Comparison with Rice Showing the Styles of Reserves Mobilization in Different Crops  

PubMed Central

Background Seed germination is a complex physiological process during which mobilization of nutrient reserves happens. In different crops, this event might be mediated by different regulatory and metabolic pathways. Proteome profiling has been proved to be an efficient way that can help us to construct these pathways. However, no such studies have been performed in soybean germinating seeds up to date. Results Proteome profiling was conducted through one-dimensional gel electrophoresis followed by liquid chromatography and tandem mass spectrometry strategy in the germinating seeds of soybean (glycine max). Comprehensive comparisons were also carried out between rice and soybean germinating seeds. 764 proteins belonging to 14 functional groups were identified and metabolism related proteins were the largest group. Deep analyses of the proteins and pathways showed that lipids were degraded through lipoxygenase dependent pathway and proteins were degraded through both protease and 26S proteosome system, and the lipoxygenase could also help to remove the reactive oxygen species during the rapid mobilization of reserves of soybean germinating seeds. The differences between rice and soybean germinating seeds proteome profiles indicate that each crop species has distinct mechanism for reserves mobilization during germination. Different reserves could be converted into starches before they are totally utilized during the germination in different crops seeds. Conclusions This study is the first comprehensive analysis of proteome profile in germinating soybean seeds to date. The data presented in this paper will improve our understanding of the physiological and biochemical status in the imbibed soybean seeds just prior to germination. Comparison of the protein profile with that of germinating rice seeds gives us new insights on mobilization of nutrient reserves during the germination of crops seeds. PMID:23460823

Han, Chao; Yin, Xiaojian; He, Dongli; Yang, Pingfang

2013-01-01

382

Dual Effect of Light on the Gibberellin- and Nitrate-Stimulated Seed Germination of Sisymbrium officinale and Arabidopsis thaliana  

PubMed Central

Red light (R) has a dual effect on the seed germination of the two related species Arabidopsis thaliana and Sisymbrium officinale. The two species provide different means to separate the light-effects. In S. officinale, stimulation of germination by R depends on the stimultaneous presence of nitrate (light-effect I). The effect of both factors is completely blocked by tetcyclacis, an inhibitor of gibberellin (GA)-biosynthesis. Addition of a mixture of gibberellins A4 and A7 (GA4+7) antagonizes the inhibition. In the absence of nitrate, R shifts germination to lower GA-requirement (light-effect II). In A. thaliana a similar second light-effect is seen on the GA-requirement of GA-deficient ga-1 mutant seeds. R stimulates germination of wild type seeds in water (light-effect I). For both species, light-effect I shows a fluence threshold value of approximately 10?5 moles per square meter, which is independent of the nitrate concentration. Increasing nitrate concentrations narrow the fluence-range required for maximal germination whereby the product of nitrate concentration and fluence value determines the germination level, indicating a multiplicative interaction between R and nitrate. Fluence-response curves for light-effect II are similar for both species. Germination occurs in the range of 10?6 to 10?2 moles per square meter fluence. The maximal level of germination is determined by the level of dark-germination and light-effect II. Increasing GA4+7 concentrations induce a shift to lower fluence values. It is shown that in the second effect the co-action of R and exogenous GA4+7 is clearly additive. It is concluded that light-effect I induces a chain of events leading to GA biosynthesis. Light-effect II seems to enhance the sensitivity of the seeds to GAs. PMID:16665951

Hilhorst, Henk W. M.; Karssen, Cees M.

1988-01-01

383

Spatial distribution of epigenetic modifications in Brachypodium distachyon embryos during seed maturation and germination.  

PubMed

Seed development involves a plethora of spatially and temporally synchronised genetic and epigenetic processes. Although it has been shown that epigenetic mechanisms, such as DNA methylation and chromatin remodelling, act on a large number of genes during seed development and germination, to date the global levels of histone modifications have not been studied in a tissue-specific manner in plant embryos. In this study we analysed the distribution of three epigenetic markers, i.e. H4K5ac, H3K4me2 and H3K4me1 in 'matured', 'dry' and 'germinating' embryos of a model grass, Brachypodium distachyon (Brachypodium). Our results indicate that the abundance of these modifications differs considerably in various organs and tissues of the three types of Brachypodium embryos. Embryos from matured seeds were characterised by the highest level of H4K5ac in RAM and epithelial cells of the scutellum, whereas this modification was not observed in the coleorhiza. In this type of embryos H3K4me2 was most evident in epithelial cells of the scutellum. In 'dry' embryos H4K5ac was highest in the coleorhiza but was not present in the nuclei of the scutellum. H3K4me1 was the most elevated in the coleoptile but absent from the coleorhiza, whereas H3K4me2 was the most prominent in leaf primordia and RAM. In embryos from germinating seeds H4K5ac was the most evident in the scutellum but not present in the coleoptile, similarly H3K4me1 was the highest in the scutellum and very low in the coleoptile, while the highest level of H3K4me2 was observed in the coleoptile and the lowest in the coleorhiza. The distinct patterns of epigenetic modifications that were observed may be involved in the switch of the gene expression profiles in specific organs of the developing embryo and may be linked with the physiological changes that accompany seed desiccation, imbibition and germination. PMID:25006668

Wolny, Elzbieta; Braszewska-Zalewska, Agnieszka; Hasterok, Robert

2014-01-01

384

Effect of seed size on protein and lipid contents, germination and imbibition in true potato seeds  

Microsoft Academic Search

Summary  Seeds of an open pollinated crop of potato (Solanum tuberosum L.) TPS-2, cv. Kufri Jyoti, were graded into four sizes. There were significant differences between grades for 100-seed weight,\\u000a the concentrations of total proteins and ethanol soluble proteins, and total lipids and phospholipids.\\u000a \\u000a Large seeds contained higher levels (% dry weight) of total proteins, ethanol soluble proteins and alkali soluble

A. K. Bhatt; T. C. Bhalla; H. O. Agrawal; M. D. Upadhya

1989-01-01

385

Proteomic investigation of the effect of salicylic acid on Arabidopsis seed germination and establishment of early defense mechanisms.  

PubMed

The influence of salicylic acid (SA) on elicitation of defense mechanisms in Arabidopsis (Arabidopsis thaliana) seeds and seedlings was assessed by physiological measurements combined with global expression profiling (proteomics). Parallel experiments were carried out using the NahG transgenic plants expressing the bacterial gene encoding SA hydroxylase, which cannot accumulate the active form of this plant defense elicitor. SA markedly improved germination under salt stress. Proteomic analyses disclosed a specific accumulation of protein spots regulated by SA as inferred by silver-nitrate staining of two-dimensional gels, detection of carbonylated (oxidized) proteins, and neosynthesized proteins with [35S]-methionine. The combined results revealed several processes potentially affected by SA. This molecule enhanced the reinduction of the late maturation program during early stages of germination, thereby allowing the germinating seeds to reinforce their capacity to mount adaptive responses in environmental water stress. Other processes affected by SA concerned the quality of protein translation, the priming of seed metabolism, the synthesis of antioxidant enzymes, and the mobilization of seed storage proteins. All the observed effects are likely to improve seed vigor. Another aspect revealed by this study concerned the oxidative stress entailed by SA in germinating seeds, as inferred from a characterization of the carbonylated (oxidized) proteome. Finally, the proteomic data revealed a close interplay between abscisic signaling and SA elicitation of seed vigor. PMID:16679420

Rajjou, Loïc; Belghazi, Maya; Huguet, Romain; Robin, Caroline; Moreau, Adrien; Job, Claudette; Job, Dominique

2006-07-01

386

The Effect of ?-Amanitin on the Arabidopsis Seed Proteome Highlights the Distinct Roles of Stored and Neosynthesized mRNAs during Germination1  

PubMed Central

To investigate the role of stored and neosynthesized mRNAs in seed germination, we examined the effect of ?-amanitin, a transcriptional inhibitor targeting RNA polymerase II, on the germination of nondormant Arabidopsis seeds. We used transparent testa mutants, of which seed coat is highly permeable, to better ascertain that the drug can reach the embryo during seed imbibition. Even with the most permeable mutant (tt2-1), germination (radicle protrusion) occurred in the absence of transcription, while subsequent seedling growth was blocked. In contrast, germination was abolished in the presence of the translational inhibitor cycloheximide. Taken together, the results highlight the role of stored proteins and mRNAs for germination in Arabidopsis and show that in this species the potential for germination is largely programmed during the seed maturation process. The ?-amanitin-resistant germination exhibited characteristic features. First, this germination was strongly slowed down, indicating that de novo transcription normally allows the synthesis of factor(s) activating the germination rate. Second, the sensitivity of germination to gibberellic acid was reduced 15-fold, confirming the role of this phytohormone in germination. Third, de novo synthesis of enzymes involved in reserve mobilization and resumption of metabolic activity was repressed, thus accounting for the failure in seedling establishment. Fourth, germinating seeds can recapitulate at least part of the seed maturation program, being capable of using mRNAs stored during development. Thus, commitment to germination and plant growth requires transcription of genes allowing the imbibed seed to discriminate between mRNAs to be utilized in germination and those to be destroyed. PMID:15047896

Rajjou, Loic; Gallardo, Karine; Debeaujon, Isabelle; Vandekerckhove, Joel; Job, Claudette; Job, Dominique

2004-01-01

387

Analysis of embryonic proteome modulation by GA and ABA from germinating rice seeds.  

PubMed

The phytohormones gibberellic acid (GA) and abscisic acid (ABA) play essential and often antagonistic roles in regulating plant growth, development, and stress responses. Using a proteomics-based approach, we examined the role of GA and ABA in the modulation of protein expression levels during seed germination. Rice seeds were treated with GA (200 microM), ABA (10 microM), ABA followed by GA, GA followed by ABA, and water as a control and then incubated for 3 days. The embryo was dissected from germinated seeds, and proteins were subjected to 2-DE. Approximately, 665 total protein spots were resolved in the 2-D gels. Among them, 16 proteins notably modulated by either GA or ABA were identified by MALDI-TOF MS. Northern analyses demonstrated that expression patterns of 13 of these 16 genes were consistent with those of the proteome analysis. Further examination of two proteins, rice isoflavone resuctase (OsIFR) and rice PR10 (OsPR10), using Western blot and immunolocalization, revealed that both are specifically expressed in the embryo but not in the endosperm and are dramatically downregulated by ABA. PMID:18686304

Kim, Sun Tae; Kang, Sun Young; Wang, Yiming; Kim, Sang Gon; Hwang, Du Hyeon; Kang, Kyu Young

2008-09-01

388

Relationship between hexokinase and cytokinin in the regulation of leaf senescence and seed germination.  

PubMed

Arabidopsis hexokinase (AtHXK1), an enzyme that catalyses hexose phosphorylation, accelerates leaf senescence, whereas the plant hormone cytokinin inhibits senescence. Previous work in our laboratory has shown that isopentenyl transferase (IPT), a key gene in the biosynthesis of cytokinin, expressed under promoters of the senescence-associated genes SAG12 or SAG13 (P(SAG12)::IPT and P(SAG13)::IPT, respectively), inhibits leaf senescence in tomato plants. To study the relationship between hexokinase and cytokinin in the regulation of leaf senescence, we created and analysed double-transgenic tomato plants expressing both AtHXK1 and either P(SAG12)::IPT or P(SAG13)::IPT. We found that expression of IPT in the double-transgenic plants could not prevent the accelerated senescence induced by over-expression of AtHXK1. Since cytokinin inhibits senescence via an apoplastic invertase that produces extracellular hexoses, whereas AtHXK1 is an intracellular mitochondria-associated hexokinase, our results suggest that intracellular sugar sensing via AtHXK1 is dominant over extracellular sugar sensing with regard to leaf senescence. Interestingly, the heterologous SAG12 and SAG13 promoters are also expressed in germinating tomato seed, around the radicle penetration zone, suggesting that seed germination involves a senescence process that is probably necessary for radicle emergence. Indeed, seed expressing P(SAG12)::IPT and P(SAG13)::IPT exhibited delayed radicle emergence, possibly due to delayed endosperm senescence. PMID:21489094

Swartzberg, D; Hanael, R; Granot, D

2011-05-01

389

The rice GERMINATION DEFECTIVE 1, encoding a B3 domain transcriptional repressor, regulates seed germination and seedling development by integrating GA and carbohydrate metabolism.  

PubMed

It has been shown that seed development is regulated by a network of transcription factors in Arabidopsis including LEC1 (LEAFY COTYLEDON1), L1L (LEC1-like) and the B3 domain factors LEC2, FUS3 (FUSCA3) and ABI3 (ABA-INSENSITIVE3); however, molecular and genetic regulation of seed development in cereals is poorly understood. To understand seed development and seed germination in cereals, a large-scale screen was performed using our T-DNA mutant population, and a mutant germination-defective1 (gd1) was identified. In addition to the severe germination defect, the gd1 mutant also shows a dwarf phenotype and abnormal flower development. Molecular and biochemical analyses revealed that GD1 encodes a B3 domain-containing transcription factor with repression activity. Consistent with the dwarf phenotype of gd1, expression of the gibberelic acid (GA) inactivation gene OsGA2ox3 is increased dramatically, accompanied by reduced expression of GA biosynthetic genes including OsGA20ox1, OsGA20ox2 and OsGA3ox2 in gd1, resulting in a decreased endogenous GA? level. Exogenous application of GA not only induced GD1 expression, but also partially rescued the dwarf phenotype of gd1. Furthermore, GD1 binds to the promoter of OsLFL1, a LEC2/FUS3-like gene of rice, via an RY element, leading to significant up-regulation of OsLFL1 and a large subset of seed maturation genes in the gd1 mutant. Plants over-expressing OsLFL1 partly mimic the gd1 mutant. In addition, expression of GD1 was induced under sugar treatment, and the contents of starch and soluble sugar are altered in the gd1 mutant. These data indicate that GD1 participates directly or indirectly in regulating GA and carbohydrate homeostasis, and further regulates rice seed germination and seedling development. PMID:23581288

Guo, Xiaoli; Hou, Xiaomei; Fang, Jun; Wei, Piwei; Xu, Bo; Chen, Mingluan; Feng, Yuqi; Chu, Chengcai

2013-08-01

390

Proteases of germinating winged-bean (Psophocarpus tetragonolobus) seeds: purification and characterization of an acidic protease.  

PubMed Central

Two major classes of protease are shown to occur in germinating winged-bean (Psophocarpus tetragonolobus) seeds, by assaying extracts at pH 8.0 and pH 5.1 with [14C]gelatin as substrate. At pH 8.0, the activity profile of the enzyme shows a steady rise throughout the period of germination, whereas the activity at the acidic pH is very low up to day 5 and then increases sharply reaching a peak on day 11, followed by an equally sharp decline. The winged-bean acidic protease (WbAP) has been purified to apparent homogeneity, as attested by a single protein band on both PAGE and SDS/PAGE. WbAP is a monomeric enzyme with a molecular mass of 35 kDa and a pH optimum of 6.0. It is a thiol protease that does not belong to the papain family and it has tightly bound Ca2+ as shown by 45Ca(2+)-exchange studies. Besides gelatin and casein, it hydrolyses a 29 kDa winged-bean protein, indicating a prospective physiological role for it in storage-protein mobilization. Immunoblot analysis shows that it occurs only in the seeds and sprouting tubers of this plant and also that it is synthesized in developing seeds just before desiccation. It appears that the newly synthesized enzyme is inactive, and activation takes place around day 6 of germination. However, neither the mechanism of activation nor the signal that triggers it is clearly understood. PMID:8573074

Usha, R; Singh, M

1996-01-01

391

Seed treatments to overcome salt and drought stress during germination in sunflower ( Helianthus annuus L.)  

Microsoft Academic Search

The treated seeds (control, KNO3 and hydropriming) of sunflower (Helianthus annuus L.) cultivar Sanbro were evaluated at germination and seedling growth for tolerance to salt (NaCl) and drought conditions induced by PEG-6000 at the same water potentials of 0.0, ?0.3, ?0.6, ?0.9 and ?1.2MPa. Electrical conductivity (EC) values of the NaCl solutions were 0.0, 6.5, 12.7, 18.4 and 23.5dSm?1, respectively.

Mehmet Demir Kaya; Gamze Okçu; Mehmet Atak; Yakup Ç?k?l?; Özer Kolsar?c?

2006-01-01

392

Enantioselectivity of the bioconversion of chiral citronellal during the inhibition of wheat seeds germination.  

PubMed

Citronellal is one of the most prominent monoterpenes present in many essential oils. Low persistence of essential oils as bioherbicides has often been addressed because of the high volatility of these compounds. Bioconversion of citronellal by wheat seeds releases less aggressive and injurious compounds as demonstrated by their diminished germination. We demonstrated that optically pure citronellal enantiomers were reduced to optically pure citronellol enantiomers with retention of the configuration both in isolated wheat embryos and endosperms. Our findings reveal the potential of essential oils as allelopathic agents providing an insight into their mechanism of action and persistence. PMID:24634071

Cavalieri, Andrea; Fischer, Ravit; Larkov, Olga; Dudai, Nativ

2014-03-01

393

Alfalfa seed germination and yield ratio and alfalfa sprout microbial keeping quality following irradiation of seeds and sprouts.  

PubMed

Foods can be treated with gamma radiation, a nonthermal food process, to inactivate foodborne pathogens and fungi, to kill insects on or in fruits and vegetables, and to increase shelf life. Gamma irradiation is especially well suited for these treatments because of its ability to penetrate commercial pallets of foods. Irradiated fruits, vegetables, poultry, and hamburger have been received favorably by the public and are now available in supermarkets. The use of irradiation on fresh alfalfa sprouts was studied to determine its effect on keeping quality as related to aerobic microbial load. After an irradiation dose of 2 kGy, the total aerobic count decreased from 10(5-8) to 10(3-5) CFU/g, and the total coliform counts decreased from 10(5-8) to 10(3-0) CFU/g. The results showed that the sprouts maintained their structure after irradiation, and the keeping quality was extended to 21 days, which is an increase of 10 days from the usual shelf life. The effect of various doses of irradiation on alfalfa seeds as measured by percent germination and yield ratio (wt/wt) of sprouts was determined. There was little effect on the percent germination, but as the dose increased, the yield ratio of alfalfa sprouts decreased. As the length of growing time increased, so did the yield ratio of the lower dose irradiated seeds (1 to 2 kGy). The irradiation process can be used to increase the shelf life of alfalfa sprouts, and irradiating alfalfa seeds at doses up to 2 kGy does not unacceptably decrease the yield ratio for production of alfalfa sprouts. PMID:11770628

Rajkowski, K T; Thayer, D W

2001-12-01

394

Does plant-derived smoke affect seed germination in dominant woody species of the Mediterranean matorral of central Chile?  

Microsoft Academic Search

Studies performed in the fire-prone Mediterranean-type climate shrublands of Australia, California, and South Africa have shown that plant-derived smoke enhances seed germination in many species. Unlike other areas with similar climate, central Chile stands out for the absence of natural fires, suggesting that smoke may not be expected to promote germination. However, anthropogenic fires have been frequent since several millennia,

S. Gómez-González; A. Sierra-Almeida; L. A. Cavieres

2008-01-01

395

Germination as a process to increase the polyphenol content and antioxidant activity of lupin seeds ( Lupinus angustifolius L.)  

Microsoft Academic Search

In this work, the effect of germination of lupin seeds (Lupinus angustifolius L., c.v. Zapatón) on bioactive phenolic compounds as well as on the antioxidant activity was studied. Phenolic compounds were analysed by HPLC-PAD-ESI\\/MS. The antioxidant activity was determined by spectrophotometry, evaluating the free radical scavenging activity of the samples. Germination produced significant changes in flavonoids and non-flavonoid phenolic compounds.

M. Dueñas; T. Hernández; I. Estrella; D. Fernández

2009-01-01

396

Effect of silver nanoparticles on rice (Oryza sativa L. cv. KDML 105) seed germination and seedling growth.  

PubMed

With the advances in nanotechnology, silver nanoparticles (AgNPs) have been applied in many industries, increasing their potential exposure level in the environment, yet their environmental safety remains poorly evaluated. The possible effects of different sized AgNPs (20, 30-60, 70-120 and 150nm diameter) on jasmine rice, Oryza sativa L. cv. KDML 105, were investigated at different concentrations (0.1, 1, 10, 100 and 1000mg/L) upon seed germination and seedling growth. The results revealed that the level of seed germination and subsequent growth of those seedlings that germinated were both decreased with increasing sizes and concentrations of AgNPs. Based on the analysis of AgNPs accumulation in plant tissues, it implied that the higher uptake was found when the seeds were treated with the smaller AgNPs, 20nm diameter AgNPs, but it was trapped in the roots rather than transported to the leaves. These resulted in the less negative effects on seedling growth, when compared to the seed soaking with the larger AgNPs with 150nm diameter. The negative effects of AgNPs were supported by leaf cell deformation when rice seeds were treated with 150-nm-diameter AgNP at the concentration of 10 or 100mg/L during seed germination. These results further strengthen our understanding of environmental safety information with respect to nanomaterials. PMID:24726943

Thuesombat, Pakvirun; Hannongbua, Supot; Akasit, Sanong; Chadchawan, Supachitra

2014-06-01

397

Effects of smoke, heat, darkness and cold stratification on seed germination of 40 species in a cool temperate zone in northern Japan.  

PubMed

The effects of smoke, heat, darkness and cold stratification on seed germination were examined for 40 species with various life history attributes. These species establish in early successional stages on a volcano and are distributed in cool temperate zones of northern Japan. Smoke decreased seed germination in 11 species and increased it in one species, Leucothoe grayana. Germination of Polygonum longisetum was enhanced by a combination of smoke and cold, and that of Aralia elata by smoke and heat. Heat increased germination for three species and decreased it for one. Cold stratification broke dormancy in seeds of 11 species. Continuous darkness decreased germination of 22 species and did not increase germination for any species, showing that approximately half of the species require light for maximum germination. Although most species are sun plants that establish in early stages of succession and/or in disturbed areas, smoke and heat do not enhance germination of these species after disturbance, even when the disturbance is fire. Germination of slender and/or large seeds tends to be decreased more by smoke, probably because of their larger surface area. Light is more important than smoke and heat for detection of disturbance and for seed germination in this region. However, despite the low fire frequency in the region, germination of a few species was increased by fire-derived stimuli. PMID:19470108

Tsuyuzaki, S; Miyoshi, C

2009-05-01

398

[Seed germination and key to seedling identification for six native tree species of wetlands from Southeast Mexico].  

PubMed

Wetland tree species are of importance for economic and restoration purposes. We describe the germination process and seedling morphology of six arboreal native species typical of Southeastern Mexico: Annona glabra, Ceiba pentandra, Pachira aquatica, Haematoxylum campechianum, Coccoloba barbadensis and Crataeva tapia. A total of 300 seeds per species were planted in a mixture of sand, cocoa plant husk and black soil (1:1:1), and maintained in a tree nursery with 30% artificial shade, from February to November of 2007. We carried out the morphological characterization, and elaborated a key to seedlings based on: 1) germination type 2) seedling axis and 3) leaf elements. P. aquatica has cryptocotylar hypogeal germination, the others have phanerocotylar epigeal germination. Germination rates were high (>86%), except for C. barbadensis (69%). PMID:20527471

Zamora-Cornelio, Luis Felipe; Ochoa-Gaona, Susana; Vargas Simón, Georgina; Castellanos Albores, Jorge; Jong, Bernardus H J de

2010-06-01

399

Chemical investigation of Cyperus distans L. and inhibitory activity of scabequinone in seed germination and seedling growth bioassays.  

PubMed

Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of ?-ciperone, cyperotundone and scabequinone, besides other common constituents. Complete assignment of the (13)C NMR data of scabequinone is being published for the first time. The inhibitory effects of C. distans extracts and scabequinone on the seed germination and seedling growth of Mimosa pudica, Senna obtusifolia and Pueraria phaseoloides were evaluated. Seed germination inhibition bioassay revealed that S. obtusifolia (52-53%) was more sensitive to the hexane and the methanol extracts at 1% than M. pudica (0-10%). Scabequinone at 250 mg L(-1) displayed seed germination inhibitions more than 50% and radicle growth reduction of more than 35% of the test species S. obtusifolia and P. phaseoloides, while the hypocotyl growth of M. pudica was significantly affected (>50%) by the quinone at the same concentration. These results demonstrate that scabequinone contributes to the overall inhibitory activities of C. distans. PMID:24941231

Vilhena, Karyme S S; Guilhon, Giselle Maria Skelding Pinheiro; Zoghbi, Maria das Graças B; Santos, Lourivaldo Silva; Souza Filho, Antonio Pedro Silva

2014-12-01

400

The community-level effect of light on germination timing in relation to seed mass: a source of regeneration niche differentiation.  

PubMed

Within a community, species may germinate at different times so as to mitigate competition and to take advantage of different aspects of the seasonal environment (temporal niche differentiation). We illustrated a hypothesis of the combined effects of abiotic and biotic competitive factors on germination timing and the subsequent upscale effects on community assembly. We estimated the germination timing (GT) for 476 angiosperm species of the eastern Tibetan Plateau grasslands under two light treatments in the field: high (i.e. natural) light and low light. We also measured the shift in germination timing (SGT) across treatments for all species. Furthermore, we used phylogenetic comparative methods to test if GT and SGT were associated with seed mass, an important factor in competitive interactions. We found a significant positive correlation between GT and seed mass in both light treatments. Additionally, small seeds (early germinating seeds) tended to germinate later and large seeds (late germinating seeds) tended to germinate earlier under low light vs high light conditions. Low light availability can reduce temporal niche differentiation by increasing the overlap in germination time between small and large seeds. In turn, reduced temporal niche differentiation may increase competition in the process of community assembly. PMID:25081830

Zhang, Chunhui; Willis, Charles G; Burghardt, Liana T; Qi, Wei; Liu, Kun; de Moura Souza-Filho, Paulo Roberto; Ma, Zhen; Du, Guozhen

2014-11-01

401

A bimodal temperature response and effect of light intensity in the photocontrol of germination of seeds in Jussiaea suffruticosa.  

PubMed

A bimodal temperature response is observed in the germination of seeds in Jussiaea suffruticosa, both under continuous and cyclic light treatments. Germination exhibits two maxima at around 25° C and at 40°, and a minimum in the region of 30-35°. The response depends on light intensity both under continuous and intermittent light treatments. This dependence is much more noticeable in the region of minimum germination (30°). Both preincubation in darkness at 35° and high light intensities (15 500 lux) tend to eliminate the bimodal temperature response. PMID:24477485

Wulff, R; Arias, I; Ponce, M; Muñoz, V

1972-12-01

402

Seed priming with chitosan improves maize germination and seedling growth in relation to physiological changes under low temperature stress.  

PubMed

Low temperature stress during germination and early seedling growth is an important constraint of global production of maize. The effects of seed priming with 0.25%, 0.50%, and 0.75% (w/v) chitosan solutions at 15 degrees C on the growth and physiological changes were investigated using two maize (Zea mays L.) inbred lines, HuangC (chilling-tolerant) and Mo17 (chilling-sensitive). While seed priming with chitosan had no significant effect on germination percentage under low temperature stress, it enhanced germination index, reduced the mean germination time (MGT), and increased shoot height, root length, and shoot and root dry weights in both maize lines. The decline of malondialdehyde (MDA) content and relative permeability of the plasma membrane and the increase of the concentrations of soluble sugars and proline, peroxidase (POD) activity, and catalase (CAT) activity were detected both in the chilling-sensitive and chilling-tolerant maize seedlings after priming with the three concentrations of chitosan. HuangC was less sensitive to responding to different concentrations of chitosan. Priming with 0.50% chitosan for about 60 approximately 64 h seemed to have the best effects. Thus, it suggests that seed priming with chitosan may improve the speed of germination of maize seed and benefit for seedling growth under low temperature stress. PMID:19489108

Guan, Ya-jing; Hu, Jin; Wang, Xian-ju; Shao, Chen-xia

2009-06-01

403

[On the mechanisms of stimulation and inhibition during germination of wheat seeds in extremely low frequency electromagnetic fields].  

PubMed

It has been shown that the effects of stimulation of germination of wheat seeds by electromagnetic field depend on the degree of membrane tension during imbibition of seeds in sucrose solutions. This provides further confirmation of the influence of electromagnetic fields on the release of proteins from the bound state on the membranes. The prolonged treatment with electromagnetic fields during the imbibition of seeds leads not only to the inhibition of germination of sprouts but also to a decrease in their germinability, which can be as strong as twofold for seeds with the initial low germinability. This is related to the desynchronization of germination processes, caused by the stimulation of the release of proteins and inhibition of another stage during the cell division, the assembly of complex structures. It is noted that the activation of the release of proteins and inhibition of their binding by the action of electromagnetic fields must elevate the cell excitability. The presumably, the excitability of cells determines the effects of magnetic storms and high solar activity on the physiological state of organisms. PMID:17477063

Aksenov, S I; Grunina, T Iu; Goriachev, S N

2007-01-01

404

Alternative strategies of seed predator escape by early-germinating oaks in Asia and North America  

PubMed Central

Early germination of white oaks is widely viewed as an evolutionary strategy to escape rodent predation; yet, the mechanism by which this is accomplished is poorly understood. We report that chestnut oak Quercus montana (CO) and white oak Q. alba (WO) (from North America), and oriental cork oak Q. variabilis (OO) and Mongolian oak Q. mongolica (MO) (from Asia) can escape predation and successfully establish from only taproots. During germination in autumn, cotyledonary petioles of acorns of CO and WO elongate and push the plumule out of the cotyledons, whereas OO and MO extend only the hypocotyls and retain the plumule within the cotyledons. Experiments showed that the pruned taproots (>6 cm) of CO and WO acorns containing the plumule successfully germinated and survived, and the pruned taproots (?12 cm) of OO and MO acorns without the plumule successfully regenerated along with the detached acorns, thus producing two seedlings. We argue that these two distinct regeneration morphologies reflect alternative strategies for escaping seed predation. PMID:22822428

Yi, Xianfeng; Yang, Yueqin; Curtis, Rachel; Bartlow, Andrew W; Agosta, Salvatore J; Steele, Michael A

2012-01-01

405

Seed germination and seedling development ecology in world-wide populations of a circumboreal Tertiary relict  

PubMed Central

Background and aims Temperate forests are disjunct in the Northern Hemisphere, having become fragmented from the earlier widespread (Tertiary) boreotropical forest. We asked ‘What are the contemporary patterns of population variation in ecological traits of a Tertiary relict in a macroecological context?’. This issue underpins our understanding of variation in populations occurring in the same biome but on different continents. Methodology We examined characters associated with root and shoot emergences among populations of Viburnum opulus in temperate forests of Asia, North America and Europe. This species has complex seedling emergence extending over several years and requiring various temperature cues. Principal results Populations varied in germination responses and clustered into groups that were only partly related to varietal status. Whereas roots (at warm temperatures) and shoots (following a cold period) simultaneously emerged from seeds of all populations when simulated dispersal occurred in winter, they were delayed in some populations when dispersal occurred in summer. Conclusions Viburnum opulus populations, some separated by 10 300 km, showed high similarity in seedling development and in germination phenology, and we suggest that stabilizing selection has played a key role in maintaining similar dormancy mechanisms. Nevertheless, there was some degree of variation in other germination characters, suggesting local adaptation. PMID:22514787

Walck, Jeffrey L.; Karlsson, Laila M.; Milberg, Per; Hidayati, Siti N.; Kondo, Tetsuya

2012-01-01

406

Alternative strategies of seed predator escape by early-germinating oaks in Asia and North America.  

PubMed

Early germination of white oaks is widely viewed as an evolutionary strategy to escape rodent predation; yet, the mechanism by which this is accomplished is poorly understood. We report that chestnut oak Quercus montana (CO) and white oak Q. alba (WO) (from North America), and oriental cork oak Q. variabilis (OO) and Mongolian oak Q. mongolica (MO) (from Asia) can escape predation and successfully establish from only taproots. During germination in autumn, cotyledonary petioles of acorns of CO and WO elongate and push the plumule out of the cotyledons, whereas OO and MO extend only the hypocotyls and retain the plumule within the cotyledons. Experiments showed that the pruned taproots (>6 cm) of CO and WO acorns containing the plumule successfully germinated and survived, and the pruned taproots (?12 cm) of OO and MO acorns without the plumule successfully regenerated along with the detached acorns, thus producing two seedlings. We argue that these two distinct regeneration morphologies reflect alternative strategies for escaping seed predation. PMID:22822428

Yi, Xianfeng; Yang, Yueqin; Curtis, Rachel; Bartlow, Andrew W; Agosta, Salvatore J; Steele, Michael A

2012-03-01

407

QTL analysis of seed germination and pre-emergence growth at extreme temperatures in Medicago truncatula  

PubMed Central

Enhancing the knowledge on the genetic basis of germination and heterotrophic growth at extreme temperatures is of major importance for improving crop establishment. A quantitative trait loci (QTL) analysis was carried out at sub- and supra-optimal temperatures at these early stages in the model Legume Medicago truncatula. On the basis of an ecophysiological model framework, two populations of recombinant inbred lines were chosen for the contrasting behaviours of parental lines: LR5 at sub-optimal temperatures (5 or 10°C) and LR4 at a supra-optimal temperature (20°C). Seed masses were measured in all lines. For LR5, germination rates and hypocotyl growth were measured by hand, whereas for LR4, imbibition and germination rates as well as early embryonic axis growth were measured using an automated image capture and analysis device. QTLs were found for all traits. The phenotyping framework we defined for measuring variables, distinguished stages and enabled identification of distinct QTLs for seed mass (chromosomes 1, 5, 7 and 8), imbibition (chromosome 4), germination (chromosomes 3, 5, 7 and 8) and heterotrophic growth (chromosomes 1, 2, 3 and 8). The three QTL identified for hypocotyl length at sub-optimal temperature explained the largest part of the phenotypic variation (60% together). One digenic interaction was found for hypocotyl width at sub-optimal temperature and the loci involved were linked to additive QTLs for hypocotyl elongation at low temperature. Together with working on a model plant, this approach facilitated the identification of genes specific to each stage that could provide reliable markers for assisting selection and improving crop establishment. With this aim in view, an initial set of putative candidate genes was identified in the light of the role of abscissic acid/gibberellin balance in regulating germination at high temperatures (e.g. ABI4, ABI5), the molecular cascade in response to cold stress (e.g. CBF1, ICE1) and hypotheses on changes in cell elongation (e.g. GASA1, AtEXPA11) with changes in temperatures based on studies at the whole plant scale. PMID:20878383

Dias, Paula Menna Barreto; Brunel-Muguet, Sophie; Durr, Carolyne; Huguet, Thierry; Demilly, Didier; Wagner, Marie-Helene

2010-01-01

408

Thermal thresholds as predictors of seed dormancy release and germination timing: altitude-related risks from climate warming for the wild grapevine Vitis vinifera subsp. sylvestris  

PubMed Central

Background and Aims The importance of thermal thresholds for predicting seed dormancy release and germination timing under the present climate conditions and simulated climate change scenarios was investigated. In particular, Vitis vinifera subsp. sylvestris was investigated in four Sardinian populations over the full altitudinal range of the species (from approx. 100 to 800 m a.s.l). Methods Dried and fresh seeds from each population were incubated in the light at a range of temperatures (10–25 and 25/10 °C), without any pre-treatment and after a warm (3 months at 25 °C) or a cold (3 months at 5 °C) stratification. A thermal time approach was then applied to the germination results for dried seeds and the seed responses were modelled according to the present climate conditions and two simulated scenarios of the Intergovernmental Panel on Climate Change (IPCC): B1 (+1·8 °C) and A2 (+3·4 °C). Key Results Cold stratification released physiological dormancy, while very few seeds germinated without treatments or after warm stratification. Fresh, cold-stratified seeds germinated significantly better (>80 %) at temperatures ?20 °C than at lower temperatures. A base temperature for germination (Tb) of 9·0–11·3 °C and a thermal time requirement for 50 % of germination (?50) ranging from 33·6 °Cd to 68·6 °Cd were identified for non-dormant cold-stratified seeds, depending on the populations. This complex combination of thermal requirements for dormancy release and germination allowed prediction of field emergence from March to May under the present climatic conditions for the investigated populations. Conclusions The thermal thresholds for seed germination identified in this study (Tb and ?50) explained the differences in seed germination detected among populations. Under the two simulated IPCC scenarios, an altitude-related risk from climate warming is identified, with lowland populations being more threatened due to a compromised seed dormancy release and a narrowed seed germination window. PMID:23071219

Orru, Martino; Mattana, Efisio; Pritchard, Hugh W.; Bacchetta, Gianluigi

2012-01-01

409

Expression of 9-cis-EPOXYCAROTENOID DIOXYGENASE4 is essential for thermoinhibition of lettuce seed germination but not for seed development or stress tolerance.  

PubMed

Thermoinhibition, or failure of seeds to germinate at warm temperatures, is common in lettuce (Lactuca sativa) cultivars. Using a recombinant inbred line population developed from a lettuce cultivar (Salinas) and thermotolerant Lactuca serriola accession UC96US23 (UC), we previously mapped a quantitative trait locus associated with thermoinhibition of germination to a genomic region containing a gene encoding a key regulated enzyme in abscisic acid (ABA) biosynthesis, 9-cis-EPOXYCAROTENOID DIOXYGENASE4 (NCED4). NCED4 from either Salinas or UC complements seeds of the Arabidopsis thaliana nced6-1 nced9-1 double mutant by restoring germination thermosensitivity, indicating that both NCED4 genes encode functional proteins. Transgenic expression of Salinas NCED4 in UC seeds resulted in thermoinhibition, whereas silencing of NCED4 in Salinas seeds led to loss of thermoinhibition. Mutations in NCED4 also alleviated thermoinhibition. NCED4 expression was elevated during late seed development but was not required for seed maturation. Heat but not water stress elevated NCED4 expression in leaves, while NCED2 and NCED3 exhibited the opposite responses. Silencing of NCED4 altered the expression of genes involved in ABA, gibberellin, and ethylene biosynthesis and signaling pathways. Together, these data demonstrate that NCED4 expression is required for thermoinhibition of lettuce seeds and that it may play additional roles in plant responses to elevated temperature. PMID:23503626

Huo, Heqiang; Dahal, Peetambar; Kunusoth, Keshavulu; McCallum, Claire M; Bradford, Kent J

2013-03-01

410

Expression of 9-cis-EPOXYCAROTENOID DIOXYGENASE4 Is Essential for Thermoinhibition of Lettuce Seed Germination but Not for Seed Development or Stress Tolerance[C][W  

PubMed Central

Thermoinhibition, or failure of seeds to germinate at warm temperatures, is common in lettuce (Lactuca sativa) cultivars. Using a recombinant inbred line population developed from a lettuce cultivar (Salinas) and thermotolerant Lactuca serriola accession UC96US23 (UC), we previously mapped a quantitative trait locus associated with thermoinhibition of germination to a genomic region containing a gene encoding a key regulated enzyme in abscisic acid (ABA) biosynthesis, 9-cis-EPOXYCAROTENOID DIOXYGENASE4 (NCED4). NCED4 from either Salinas or UC complements seeds of the Arabidopsis thaliana nced6-1 nced9-1 double mutant by restoring germination thermosensitivity, indicating that both NCED4 genes encode functional proteins. Transgenic expression of Salinas NCED4 in UC seeds resulted in thermoinhibition, whereas silencing of NCED4 in Salinas seeds led to loss of thermoinhibition. Mutations in NCED4 also alleviated thermoinhibition. NCED4 expression was elevated during late seed development but was not required for seed maturation. Heat but not water stress elevated NCED4 expression in leaves, while NCED2 and NCED3 exhibited the opposite responses. Silencing of NCED4 altered the expression of genes involved in ABA, gibberellin, and ethylene biosynthesis and signaling pathways. Together, these data demonstrate that NCED4 expression is required for thermoinhibition of lettuce seeds and that it may play additional roles in plant responses to elevated temperature. PMID:23503626

Huo, Heqiang; Dahal, Peetambar; Kunusoth, Keshavulu; McCallum, Claire M.; Bradford, Kent J.

2013-01-01

411

Synthesis and degradation of the major allergens in developing and germinating soybean seed.  

PubMed

Gly m Bd 28K, Gly m Bd 30K and Gly m Bd 60K are the major soybean (Glycine max (L.) Merr.) allergens limiting the consumption of a good protein source for sensitive individuals. However, little is known about their temporal-spatial expression during seed development and upon germination. The present data shows that soy allergens accumulated in both the embryonic axes and cotyledon, but expression patterns differed depending on the specific allergen. Allergens accumulated sooner and to a greater level in cotyledons than in embryonic axes. Gly m Bd 28 began at 14 d after flowering, 7 to 14 d earlier than Gly m Bd 30K and Gly m Bd 60K. Comparatively, their degradation was faster and more profound in embryonic axes than in cotyledons. Gly m Bd 60K began to decline at 36 h after imbibition and remained detectable up to 108 h in cotyledons. In contrast, the Glym Bd 60K protein was reduced at 24 h, and eventually disappeared at 96 h . In cotyledons Gly m Bd 28K first declined at 24 h, then increased from 36 h to 48 h, followed by its large reduction at 72 h after seed germination. These findings provide useful information on soy allergen biosynthesis and will help move forward towards developing a hypoallergenic soybean for safer food. PMID:22123664

Wu, Yong-Mei; Guan, Rong-Xia; Liu, Zhang-Xiong; Li, Run-Zhi; Chang, Ru-Zhen; Qiu, Li-Juan

2012-01-01

412

Effects of phenanthrene on seed germination and some physiological activities of wheat seedling.  

PubMed

Polycyclic aromatic hydrocarbons (PAHs) are one of the highly persistent organic pollutants, and they are toxic to plants and other living organisms, including human beings. To analyze the response of higher plant to PAHs, we investigated the effects of phenanthrene (PHE) on seed germination and various physiological changes of wheat seedlings. Specifically, we investigated growth, chlorophyll content, lipid peroxidation (LPO), activities of antioxidant enzymes and H2O2 accumulation. The results showed that PHE inhibited seed germination, affected the growth and chlorophyll level of wheat seedlings. Furthermore, PHE elevated the levels of LPO and induced H2O2 accumulation in leaf tissues in a dose-dependent manner, accompanied by the changes in the antioxidant status. The activities of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), displayed a decreasing trend with the increasing of PHE concentration. The results indicated that PHE could exert oxidative damages in the early development stage of wheat and the harmfulness occurred mainly in samples with higher concentrations of PHE. PMID:24581803

Wei, Haiying; Song, Shanjuan; Tian, Hongling; Liu, Ting

2014-02-01

413

Purification and characterization of an alpha-glucosidase from germinating millet seeds.  

PubMed

An alpha-glucosidase (alpha-D-glucoside glucohydrolase, EC 3.2.1.20) was isolated from germinating millet (Panicum miliaceum L.) seeds by a procedure that included ammonium sulfate fractionation, chromatography on CM-cellulofine/Fractogel EMD SO(3), Sephacryl S-200 HR and TSK gel Phenyl-5 PW, and preparative isoelectric focusing. The enzyme was homogenous by SDS-PAGE. The molecular weight of the enzyme was estimated to be 86,000 based on its mobility in SDS-PAGE and 80,000 based on gel filtration with TSKgel super SW 3000, which showed that it was composed of a single unit. The isoelectric point of the enzyme was 8.3. The enzyme readily hydrolyzed maltose, malto-oligosaccharides, and alpha-1,4-glucan, but hydrolyzed polysaccharides more rapidly than maltose. The K(m) value decreased with an increase in the molecular weight of the substrate. The value for maltoheptaose was about 4-fold lower than that for maltose. The enzyme preferably hydrolyzed amylopectin in starch, but also readily hydrolyzed nigerose, which has an alpha-1,3-glucosidic linkage and exists as an abnormal linkage in the structure of starch. In particular, the enzyme readily hydrolyzed millet starch from germinating seeds that had been degraded to some extent. PMID:15845403