Sample records for germinating radish seeds

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  2. THE EFFECTS OF COUMARIN ON RADISH SEED GERMINATION AND RADICLE ELONGATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  3. Effects of Ni 2+ during the early phases of radish ( Raphanus sativus) seed germination

    Microsoft Academic Search

    Luca Espen; Livia Pirovano; Sergio M. Cocucci

    1997-01-01

    The effects of Ni2+ on Raphanus sativus seeds during the first 48 h of germination were investigated. Increasing concentrations of Ni2+ (0, 80, 100, 200 and 400 ?M) progressively inhibited the growth of radish seedlings. In parallel, Ni2+ affected the restoration of reabsorption of K+ and Mg2+ and the release of Ca2+ into the incubation medium. The transport mechanisms appeared

  4. Time dependence of bioactive compounds and antioxidant capacity during germination of different cultivars of broccoli and radish seeds

    Microsoft Academic Search

    Cristina Martinez-Villaluenga; Elena Peñas; Ewa Ciska; Mariusz K. Piskula; Halina Kozlowska; Concepción Vidal-Valverde; Juana Frias

    2010-01-01

    Optimisation of the germination process of different cultivars of broccoli (Brassica oleracea var. italica cv. Lucky, cv. Tiburon and cv. Belstar) and radish (Raphanus sativus cv. Rebel and cv. Bolide) seeds in relation to the content of glucosinolates (GLS), vitamin C and total antioxidant capacity was carried out in order to maximise the health-promoting properties of Brassica sprouts. The content

  5. Seed Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Initiation of seed germination is a critical decision for plants. It is important for seed populations under natural conditions to spread the timing of germination of individual seeds to maximize the probability of species survival. Therefore, seeds have evolved the multiple layers of mechanisms tha...

  6. Nickel toxicity on seed germination and growth in radish (Raphanus sativus) and its recovery using copper and boron.

    PubMed

    Yadav, Shiv Shankar; Shukla, Rajni; Sharma, Y K

    2009-05-01

    Effect of various concentrations of nickel (100, 200, 500 and 1000 microM) and recovery treatments of boron (50 and 100 microM) and copper (15 and 75 microM) each with 200 microM and 500 microM of nickel on germination, growth, biomass, chlorophyll, carotenoids, pheophytin, amylase, protein, sugar as well as activity of catalase and peroxidase were studied in radish (Raphanus sativus cv. Early menu) seedlings. Nickel treatments caused a considerable reduction in germination percentage, growth and biomass. The different pigments were also decreased with nickel treatments. However boron addition with nickel recovered the negative effect on pigment contents. Among biochemical estimations, amylase activity and total proteins were found to be reduced in nickel treatments. Peroxidase and catalase activity were induced other than higher total sugar with nickel treatments. The combination of nickel with boron resulted into increased protein contents. This combination also reduced the catalase and peroxidase activity. The influence of nickel with copper failed to produce significant recovery except 200 microM nickel in combination with 15 microM copper with regard to catalase and peroxidase activity. The effect of nickel on hydrolyzing enzyme amylase was observed to be inhibitory resulting into poor germination followed by poor seedlings growth. The stress protecting enzymes peroxidase and catalase seem to be induced under the influence of nickel, and providing protection to the seedlings. The application of boron with nickel showed improved germination and growth. The level of catalase and peroxidase were found to be significantly reduced showing normal growth and biomass of seedlings. PMID:20120479

  7. Watermelon Seed Germination

    E-print Network

    Watermelon Seed Germination Purdue University Cooperative Extension Service BP-62 Seed Germination seeds of standard watermelon. The concept of seedless fruit seem to fit the lifestyle of consumers who bars and fruit salads. Seedless watermelon are pro- duced from seed which have three sets

  8. Easy PEAsy Seed Germination

    NSDL National Science Digital Library

    2012-04-09

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

  9. Radishes

    NSDL National Science Digital Library

    N/A N/A (None; )

    2007-07-04

    Radishes have roots. These roots help the radishes absorb nutrients and water from the soil. The radish and root are buried underneath the soil. The green leaves are above soil to gather sunlight for the plant.

  10. Impact of germination on phenolic content and antioxidant activity of 13 edible seed species

    Microsoft Academic Search

    Bolívar A. Cevallos-Casals; Luis Cisneros-Zevallos

    2010-01-01

    The aim of this work was to test 13 edible seeds for the levels of phenolic compounds and the antioxidant activity (TAC) at different germination states (dormant, imbibed and 7d sprouts). Selected seeds included mungbean, alfalfa, fava, fenugreek, mustard, wheat, broccoli, sunflower, soybean, radish, kale, lentil and onion. Accumulated phenolics (mg chlorogenic acid equivalent, CAE) and TAC (?g Trolox equivalent)

  11. Chemical and irradiation treatments for killing Escherichia coli O157:H7 on alfalfa, radish, and mung bean seeds.

    PubMed

    Bari, M L; Nazuka, E; Sabina, Y; Todoriki, S; Isshiki, K

    2003-05-01

    In this study, the effectiveness of dry-heat treatment in combination with chemical treatments (electrolyzed oxidizing [EO] water, califresh-S, 200 ppm of active chlorinated water) with and without sonication in eliminating Escherichia coli O157:H7 on laboratory-inoculated alfalfa, radish, and mung bean seeds was compared with that of dry-heat treatment in combination with irradiation treatment. The treatment of mung bean seeds with EO water in combination with sonication followed by a rinse with sterile distilled water resulted in reductions of approximately 4.0 log10 CFU of E. coli O157:H7 per g. whereas reductions of ca. 1.52 and 2.64 log10 CFU/g were obtained for radish and alfalfa seeds. The maximum reduction (3.70 log10 CFU/g) for mung bean seeds was achieved by treatment with califresh-S and chlorinated water (200 ppm) in combination with sonication and a rinse. The combination of dry heat, hot EO water treatment, and sonication was able to eliminate pathogen populations on mung bean seeds but was unable to eliminate the pathogen on radish and alfalfa seeds. Other chemical treatments used were effective in greatly reducing pathogen populations on radish and alfalfa seeds without compromising the quality of the sprouts, but these treatments did not result in the elimination of pathogens from radish and alfalfa seeds. Moreover, a combination of dry-heat and irradiation treatments was effective in eliminating E. coli O157:H7 on laboratory-inoculated alfalfa, radish, and mung bean seeds. An irradiation dose of 2.0 kGy in combination with dry heat eliminated E. coli O157:H7 completely from alfalfa and mung bean seeds, whereas a 2.5-kGy dose of irradiation was required to eliminate the pathogen completely from radish seeds. Dry heat in combination with irradiation doses of up to 2.0 kGy did not unacceptably decrease the germination percentage for alfalfa seeds or the length of alfalfa sprouts but did decrease the lengths of radish and mung bean sprouts. PMID:12747683

  12. Phytotoxicity of nanoparticles: inhibition of seed germination and root growth.

    PubMed

    Lin, Daohui; Xing, Baoshan

    2007-11-01

    Plants need to be included to develop a comprehensive toxicity profile for nanoparticles. Effects of five types of nanoparticles (multi-walled carbon nanotube, aluminum, alumina, zinc, and zinc oxide) on seed germination and root growth of six higher plant species (radish, rape, ryegrass, lettuce, corn, and cucumber) were investigated. Seed germination was not affected except for the inhibition of nanoscale zinc (nano-Zn) on ryegrass and zinc oxide (nano-ZnO) on corn at 2000 mg/L. Inhibition on root growth varied greatly among nanoparticles and plants. Suspensions of 2000 mg/L nano-Zn or nano-ZnO practically terminated root elongation of the tested plant species. Fifty percent inhibitory concentrations (IC50) of nano-Zn and nano-ZnO were estimated to be near 50mg/L for radish, and about 20mg/L for rape and ryegrass. The inhibition occurred during the seed incubation process rather than seed soaking stage. These results are significant in terms of use and disposal of engineered nanoparticles. PMID:17374428

  13. Seed germination characteristics of Halogeton glomeratus

    Microsoft Academic Search

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

    2001-01-01

    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,

  14. Oxygen requirement of germinating flax seeds.

    PubMed

    Kuznetsov, Oleg A; Hasenstein, K H

    2003-01-01

    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 microliters O2 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% O2 we determined the lower limit of reliable germination to be 10 vol. % O2 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. PMID:14686434

  15. Oxygen requirement of germinating flax seeds

    NASA Technical Reports Server (NTRS)

    Kuznetsov, Oleg A.; Hasenstein, K. H.; Hasentein, K. H. (Principal Investigator)

    2003-01-01

    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 microliters O2 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% O2 we determined the lower limit of reliable germination to be 10 vol. % O2 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. c2003 Published by Elsevier Ltd on behalf of COSPAR.

  16. Oxygen requirement of germinating flax seeds

    NASA Astrophysics Data System (ADS)

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

    2003-05-01

    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.

  17. SEED GERMINATION AND VIABILITY OF WYOMING SAGEBRUSH IN NORTHERN NEVADA

    Microsoft Academic Search

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

    2005-01-01

    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

  18. Food safety evaluation of broccoli and radish sprouts

    Microsoft Academic Search

    Cristina Martínez-Villaluenga; Juana Frías; Piotr Gulewicz; Krzysztof Gulewicz; Concepción Vidal-Valverde

    2008-01-01

    Three cultivars of broccoli seeds (Brassica oleracea var. italica), cv. Tiburon, cv. Belstar and cv. Lucky, and two cultivars of radish seeds (Raphanus sativus), cv. Rebel and cv. Bolide, were germinated for three and five days and safety aspects such as microbiological counts and biogenic amines were investigated. Cytotoxicity evaluation was also carried out. Broccoli and radish sprouts contained numbers

  19. Effects of Air Temperature on Seed Germination

    NSDL National Science Digital Library

    Amy MacArthur

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

  20. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Number of seeds for germination. 201.54 Section 201.54 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  1. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Source of seeds for germination. 201.53 Section 201.53 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  2. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Number of seeds for germination. 201.54 Section 201.54 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  3. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...2014-01-01 2014-01-01 false Source of seeds for germination. 201.53 Section 201.53 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  4. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Number of seeds for germination. 201.54 Section 201.54 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  5. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Number of seeds for germination. 201.54 Section 201.54 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  6. 7 CFR 201.54 - Number of seeds for germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...2012-01-01 2012-01-01 false Number of seeds for germination. 201.54 Section 201.54 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  7. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...2011-01-01 2011-01-01 false Source of seeds for germination. 201.53 Section 201.53 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  8. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...2013-01-01 2013-01-01 false Source of seeds for germination. 201.53 Section 201.53 Agriculture...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Germination Tests in the...

  9. Organic acids as seed germination inhibitors

    Microsoft Academic Search

    A. Saviozzi; R. Riffaldi

    1994-01-01

    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

  10. Precision metering of germinated seeds 

    E-print Network

    Elliot, Gregory Lawrence

    1990-01-01

    Seeds Purpose and Objectives REVIEW OF LITERATURE Precision Planters and Meters for Dry Seeds Trapping Seeds in Cells Trapping Seeds by Air Pressure Using Other Methods for Dry Seeds Planters and Meters for Seeds in Liquid Extruding a Continuous... require only that a certain plant population density be achieved. Willey (1982) points out that this type of crop may be planted with nonprecision planters or broadcast seeders, which control only the rate at which seeds are distributed. However...

  11. Photoinduced Seed Germination of Oenothera biennis L

    PubMed Central

    Ensminger, Peter A.; Ikuma, Hiroshi

    1987-01-01

    The photoinduction period of Oenothera biennis L. seed germination was analyzed by varying the photoinduction temperature and by substituting red light pulses for continuous red light. At 24°C, seeds require 36 hours of continuous red light for maximal percent germination. The optimal photoinduction temperature is 32°C, with higher and lower temperatures being strongly inhibitory. A 30 minute exposure to far-red light, given immediately after a red light period of 1 to 36 hours, reduces germination by about 25%. Seeds escape from far-red inhibition with a half-time of 5 to 10 hours, depending on the length of the red exposure that precedes the far-red light. Periodic 15 minute pulses of red light can substitute for continuous red light in stimulating germination. Ted red light pulses, with 6 hours of darkness between successive pulses, cause maximal germination. The response to periodic red light is fully reversible by far-red light. Probit analysis of the periodic light response shows that as the length of the dark periods between successive pulses increases, less incident light is needed to induce germination but the population variance in light sensitivity remains constant. Probit analysis of the temperature response shows that as the photoinduction temperature increases from 16 to 32°C, less incident light is needed to induce germination and the population variance in light sensitivity also increases. PMID:16665825

  12. Nitric oxide accelerates seed germination in warm-season grasses

    Microsoft Academic Search

    Gautam Sarath; Paul C. Bethke; Russell Jones; Lisa M. Baird; Guichuan Hou; Robert B. Mitchell

    2006-01-01

    The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25°C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin

  13. Determination of kinetic and thermodynamic parameters that describe isothermal seed germination: A student research project

    NASA Astrophysics Data System (ADS)

    Hageseth, Gaylord T.

    1982-02-01

    Students under the supervision of a faculty member can collect data and fit the data to the theoretical mathematical model that describes the rate of isothermal seed germination. The best-fit parameters are interpreted as an initial substrate concentration, product concentration, and the autocatalytic reaction rate. The thermodynamic model enables one to calculate the activation energy for the substrate and product, the activation energy for the autocatalytic reaction, and changes in enthalpy, entropy, and the Gibb's free energy. Turnip, lettuce, soybean, and radish seeds have been investigated. All data fit the proposed model.

  14. Seed biology and in vitro seed germination of Cypripedium.

    PubMed

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

    2014-12-01

    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

  15. Seed germination ecology in southwestern Western Australia

    Microsoft Academic Search

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

    1993-01-01

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

  16. Germination of yaupon (Ilex vomitoria Ait.) seed 

    E-print Network

    Fleming, Carl Michael

    1970-01-01

    quantities' of lipids, and exhibit littl morphological differentiation in relation tc the duration of fruit persistence on the parent plant. Di-hydroxy phenols tended to increase with increased fruit persistence. A compound s'miler o csffeic acid.... or. germination, radicle growth and coleoptile growth of Ouauah wheat. Visualization tests for various selected phenolics, related compounds and seed extract uf. yaupo!! seed. 21 The erfe"t of various concentratio !s of cuffeic acid in water ou...

  17. Characterisation of germinating and non-germinating wheat seeds by nuclear magnetic resonance (NMR) spectroscopy.

    PubMed

    Krishnan, P; Joshi, D K; Nagarajan, Shantha; Moharir, A V

    2004-02-01

    Experiments were conducted to characterise the changes, especially of water status in germinating and non-germinating wheat seeds by nuclear magnetic resonance (NMR) spectroscopy. NMR relaxation time ( T(2)) measurements showed tri-phasic or bi-phasic characteristics during different stages of hydration, depending on the seed's ability to germinate. Component analysis of T(2) data revealed the existence of only two components, bound and bulk water, in dry seeds. In contrast, both the germinating and non-germinating wheat seeds had a three-component water proton system (bound, bulk and free water) in phase I of hydration. During the lag phase (phase II) of hydration, bulk water component of non-germinating seeds disappeared completely, resulting in a two component water proton system. Nevertheless, the three component water proton system was observed in the germinating seeds in phase II. Following phase II, rapid hydration (phase III) was observed in germinating seeds only. Water protons were re-organised and there were increases in bulk and free water but decreases in bound water concomitantly. Comparison of the physical state of water in these seeds by NMR spectroscopy with that of tissue leachate conductivity measurement suggests that the seed membrane system was affected more evidently in non-germinating seeds, leading to the disorganised cell structure. The present study provides evidence that the reorganisation of physical state of water in germinating wheat seeds during hydration is essential for its subsequent event of germination. PMID:12904911

  18. Decontamination method using heat and relative humidity for radish seeds achieves a 7-log reduction of Escherichia coli O157:H7 without affecting product quality.

    PubMed

    Kim, Y B; Kim, H W; Song, M K; Rhee, M S

    2015-05-18

    We developed a novel decontamination method to inactivate Escherichia coli O157:H7 on radish seeds without adversely affecting seed germination or product quality. The use of heat (55, 60, and 65 °C) combined with relative humidity (RH; 25, 45, 65, 85, and 100%) for 24h was evaluated for effective microbial reduction and preservation of seed germination rates. A significant two-way interaction of heat and RH was observed for both microbial reduction and germination rate (P<0.0001). Increases in heat and RH were associated with corresponding reductions in E. coli O157:H7 and in germination rate (P<0.05). The order of lethality for the different treatments was generally as follows: no treatment <55 °C/25-65% RH ?60 °C/25-45% RH ?65 °C/25% RH <55 °C/85% RH =60 °C/65% RH <55 °C/100% RH =60 °C/85-100% RH =65 °C/45-100% RH. The most effective condition, 65 °C/45% RH, completely inactivated E. coli O157:H7 on the seeds (7.0 log CFU/g reduction) and had no significant effect on the germination rate (85.4%; P>0.05) or product quality. The method uses only heat and relative humidity without chemicals, and is thus applicable as a general decontamination procedure in spout producing plants where the use of growth chambers is the norm. PMID:25732001

  19. Autotoxic inhibition of seed germination by Typha latifolia : an evaluation

    Microsoft Academic Search

    James B. Grace

    1983-01-01

    Seeds of Typha latifolia were exposed to leaf extracts, leaf pieces, and soil water from adult plants of T. latifolia. In liquid culture, only extracts of concentration greater than or equal to 3% (dry weight to volume) inhibited seed germination. Adding soil to the liquid cultures increased the inhibition of seed germination by extracts. The inhibitory effects of extracts were

  20. Factors influencing germination of hybrid plantain seeds in soil

    Microsoft Academic Search

    Boniface D. Dumpe; E. C. W. Wokoma

    2003-01-01

    Seed set in Musa spp. L. is known to vary greatly among seed-fertile cultivars, but germinate at an intractably low rate in soil thus making breeding of plantains and bananas difficult. This paper is a report on the influence and significance of fungicide treatments and other factors on the germination of hybrid plantain seeds. Bunches of hybrid plantain crosses were

  1. Repeated quick hot-and-chilling treatments for the inactivation of Escherichia coli O157:H7 in mung bean and radish seeds.

    PubMed

    Bari, Md Latiful; Sugiyama, Jun; Kawamoto, Shinnichi

    2009-01-01

    The majority of the seed sprout-related outbreaks have been associated with Escherichia coli O157:H7. Therefore, it is necessary to find an effective method to inactivate these organisms on the seeds prior to sprouting. This study was conducted to assess the effectiveness of repeated quick hot-and-chilling treatments with various chemicals to inactivate E. coli O157:H7 populations inoculated onto mung bean and radish seeds intended for sprout production and to determine the effect of these treatments on seed germination. The treatment time was 20 sec for quick hot and 20 sec for quick chilling in one repeat. Likewise up to five repeats were done throughout the experiments. The chemicals used for this study were electrolyzed acidic (EO) water, phytic acid (0.05%), oxalic acid (3%), surfcera(R), and alpha-torino water(R), and distilled water was used as control. The quick hot treatment was done with 75 degrees C, 70 degrees C, and 60 degrees C, and the chilling temperature was 0 degrees C. The treated seeds were then assessed for the efficacy of this treatment in reducing populations of the pathogens and the effects of repeated quick hot-and-chilling treatments on germination yield. It was found that repeating treatment at 75 degrees C for two or three repeats with phytic acid and oxalic acid could reduce 4.38-log colony-forming unit (CFU)/g of E. coli O157:H7 in mung bean seeds. EO water and distilled water were found equally effective at 75 degrees C for four or five repeats to inactivate E. coli O157:H7 in mung bean seeds. However, alpha-torino water(R) and surfcera(R) were not found effective in comparison to other sanitizers used in this experiment. Irrespective of sanitizer used, the germination yield of the mung bean seed was not affected significantly. On the other hand, distilled water, EO water, and alpha-torino water(R) at 75 degrees C for five repeats were found effective in reducing 5.80-log CFU/g of E. coli O157:H7 in radish seeds; however, the germination yield of the seed was affected significantly. Therefore, repeated quick hot-and-chilling treatments could be useful to decontaminate mung bean seeds intended for sprout production. PMID:19061368

  2. Seed germination of GA-insensitive sleepy1 mutants does not require RGL2 protein disappearance in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed germination is a complex developmental process regulated by phytohormones. The phytohormone abscisic acid (ABA) inhibits seed germination, whereas gibberellin (GA) stimulates seed germination. In tomato and Arabidopsis, GA is clearly required for seed germination. Recent evidence suggests tha...

  3. Presoaking of seeds enhances pressure inactivation of E. coli O157:H7 and Salmonella spp. on crimson clover, red clover, radish and broccoli seeds

    Microsoft Academic Search

    Hudaa Neetoo; Haiqiang Chen

    2010-01-01

    The application of high hydrostatic pressure (HHP) at a level of 600MPa at 20°C to decontaminate crimson clover, red clover, radish and broccoli seeds inoculated with E. coli O157:H7 and Salmonella were evaluated. Salmonella was generally more pressure-resistant than E. coli O157:H7 on clover and radish seeds except on broccoli seeds where the trend was reversed. In addition, the application

  4. Nitric oxide accelerates seed germination in warm-season grasses.

    PubMed

    Sarath, Gautam; Bethke, Paul C; Jones, Russell; Baird, Lisa M; Hou, Guichuan; Mitchell, Robert B

    2006-05-01

    The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25 degrees C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin acted synergistically with SNP and nitrite in promoting seed germination. Acidified nitrite, an alternate NO donor also significantly stimulated seed germination. Interestingly, sodium cyanide, potassium ferricyanide and potassium ferrocyanide at 200 microM strongly enhanced seed germination as well, whereas potassium chloride was without effect. Ferrocyanide and cyanide stimulation of seed germination was blocked by an NO scavenger. Incubation of seeds with a fluorescent NO-specific probe provided evidence for NO production in germinating switchgrass seeds. Abscisic acid (ABA) at 10 microM depressed germination, inhibited root elongation and essentially abolished coleoptile emergence. SNP partially overcame ABA effects on radicle emergence but did not overcome the effects of ABA on coleoptile elongation. Light microscopy indicated extension of the radicle and coleoptiles in seeds maintained on water or on SNP after 2 days. In contrast, there was minimal growth of the radicle and coleoptile in ABA-treated seeds even after 3-4 days. These data indicate that seed germination of warm-season grasses is significantly influenced by NO signaling pathways and document that NO could be an endogenous trigger for release from dormancy in these species. PMID:16369800

  5. Effect of fungicide on Wyoming big sagebrush seed germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Because fungal infection may complicate both the logistics and the interpretation of germination tests, seeds are sometimes treated with chemical fungicides. Fungicides may reduce the germination rate and/or germination percentage, and should be avoided unless fungal contamination is severe enough ...

  6. Investigating the Influence of Karrikins on Seed Germination

    ERIC Educational Resources Information Center

    de Beer, Josef

    2012-01-01

    Recent research has identified a karrikin (a butenolide derative) known as 3-methyl-2H-furo[2,3-c]pyran-2-one, formed from burning cellulose, that stimulates seed germination. Here, I present ideas on how to investigate the influence of karrikins on seed germination in the laboratory.

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

    Microsoft Academic Search

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

    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

  8. Variation in seed and germination characteristics among Juniperus procera populations in Ethiopia

    Microsoft Academic Search

    Negash Mamo; Mebrate Mihretu; Miftah Fekadu; Mulualem Tigabu; Demel Teketay

    2006-01-01

    Variations in seed and germination characteristics among nine Juniperus procera populations in Ethiopia were evaluated. Bulk seed samples were collected and examined for variations in number of seeds per cone, seed length, width, 1000-seed weight and germination in the laboratory and nursery. In the laboratory, the effect of light conditions on seed germination was tested by incubating the seeds under

  9. Effect of fungicide on Wyoming big sagebrush seed germination

    Microsoft Academic Search

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

    2011-01-01

    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

  10. Effect of fungicide on Wyoming big sagebrush seed germination

    Microsoft Academic Search

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

    2011-01-01

    :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

  11. Rapid and Effective Germination Methods for Overcoming Seed Dormancy in Annual Canarygrass

    Microsoft Academic Search

    M. A. Matus-Cádiz; P. Hucl

    2005-01-01

    Mediterranean climates (P. aquatica) (Carlson et al., 1996). Dormancy in pedigreed Phalaris seed can lead to unsatisfactory Seed dormancy, thetemporary failure of aviable seed germination in seed testing. The objective was to determine the effec- to germinate (Simpson, 1990), reduces germination per- tiveness of recommended germination methods in overcoming seed dormancy in annual canarygrass (P. canariensis L.). In 2003, 'CDC

  12. Mitochondrial biogenesis in plants during seed germination.

    PubMed

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

    2014-11-01

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

  13. Beta-amylase in germinating millet seeds.

    PubMed

    Yamasaki, Yoshiki

    2003-11-01

    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

  14. Pre-treating Seed to Enhance Germination of Desert Shrubs

    SciTech Connect

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

    2002-06-01

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

  15. Improving seed germination of native perennial Phlox longifolia

    Microsoft Academic Search

    2009-01-01

    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

  16. Proteomic insights into seed germination in response to environmental factors.

    PubMed

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

    2013-06-01

    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

  17. Studies on the molecular mechanisms of seed germination.

    PubMed

    Han, Chao; Yang, Pingfang

    2015-05-01

    Seed germination that begins with imbibition and ends with radicle emergence is the first step for plant growth. Successful germination is not only crucial for seedling establishment but also important for crop yield. After being dispersed from mother plant, seed undergoes continuous desiccation in ecosystem and selects proper environment to trigger germination. Owing to the contribution of transcriptomic, proteomic, and molecular biological studies, molecular aspect of seed germination is elucidated well in Arabidopsis. Recently, more and more proteomic and genetic studies concerning cereal seed germination were performed on rice (Oryza sativa) and barley (Hordeum vulgare), which possess completely different seed structure and domestication background with Arabidopsis. In this review, both the common features and the distinct mechanisms of seed germination are compared among different plant species including Arabidopsis, rice, and maize. These features include morphological changes, cell and its related structure recovery, metabolic activation, hormone behavior, and transcription and translation activation. This review will provide more comprehensive insights into the molecular mechanisms of seed germination. PMID:25597791

  18. Impact of cold storage on glucosinolate levels in seed-sprouts of broccoli, rocket, white radish and kohlrabi

    Microsoft Academic Search

    Lesleigh E. Force; Timothy J. O’Hare; Lung S. Wong; Donald E. Irving

    2007-01-01

    The effect of cold storage on glucosinolate concentration was examined in 7-day-old seed-sprouts of broccoli, kohl rabi, white radish and rocket. Principal glucosinolates identified were glucoraphanin and glucoerucin (in broccoli, kohl rabi and rocket), glucoiberin (in broccoli and kohl rabi), and glucoraphenin and glucodehydroerucin (in white radish). Generally, sprouts showed no significant changes in individual glucosinolate concentrations during storage at

  19. Volatile Metabolites Controlling Germination in Buried Weed Seeds

    PubMed Central

    Holm, Robert E.

    1972-01-01

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

  20. Volatile metabolites controlling germination in buried weed seeds.

    PubMed

    Holm, R E

    1972-08-01

    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

  1. Seed size and emergence time within a stand of wild radish ( Raphanus raphanistrum L.): the establishment of a fitness hierarchy

    Microsoft Academic Search

    Maureen L. Stanton

    1985-01-01

    To determine the role of seed size in creating adult plants of different reproductive success, individual seedlings were marked and periodically censused in a natural stand of wild radish (Raphanus raphanistrum L.) in Hamden, Connecticut. Maximum cotyledon witdth is a useful field estimator of seed weight in this species, although dramatic variation in the availability of water can modify this

  2. Seed germination of endemic species from Kerguelen phytogeographic zone

    Microsoft Academic Search

    D. W. H. Walton

    1997-01-01

    Seeds of six endemic species and two circumpolar species were collected from several sites on Kerguelen and tested for germination\\u000a between 5 and 25°C on thermogradient bars. Pringlea antiscorbutica and Colobanthus kerguelensis had a near 100% viability with an initial germination temperature of ca. 24°C. Colobanthus attained nearly 100% viability from 5 to 25°C whereas Pringlea germination declined markedly below

  3. Photocontrol of seed germination in Impatiens wallerana Hook. f

    Microsoft Academic Search

    Rogeria Pereira de Souza; Maria de Fátima A. Pereira

    1994-01-01

    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

  4. Long-Lived Messenger RNA: Evidence from Cotton Seed Germination

    Microsoft Academic Search

    Leon Dure; Larry Waters

    1965-01-01

    In germinating cotton embryos the partial inhibition of RNA synthesis by actinomycin D does not inhibit the incorporation of leucine-14C into soluble protein nor cause a loss of polyribosomes during the first 16 hours of germination. This suggests that the protein synthesis observed during this period is directed by messenger RNA which exists in the mature seed and which is

  5. Ecological genetics of seed germination regulation in Bromus tectorum L

    Microsoft Academic Search

    Susan E. Meyer; Phil S. Allen

    1999-01-01

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

  6. G Protein Signaling in the Regulation of Arabidopsis Seed Germination

    NSDL National Science Digital Library

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

    2005-11-01

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

  7. Methods toward improving 'Grande Rio 66' pepper seed germination

    E-print Network

    Rogers, Barbara Anna

    1980-01-01

    METHODS TOWARD IMPROVING 'GRANDE RIO 66' PEPPER SEED GERMINATION A Thesis by BARBARA ANNA ROGERS Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE May... 1980 Major Subject: Horticulture METHODS TONARD IMPROVING 'GRANDE RIO 66' PEPPER SEED GERMINATION A Thesis by BARBARA ANNA ROGERS Approved as to style and content by: Chairman of Committee Head of epartment em er Member May 1980 ABSTRACT...

  8. The role of the GA signaling SLY1 in Arabidopsis seed germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed dormancy, afterripening, and germination are complex developmental process regulated by phytohormones. The phytohormone abscisic acid (ABA) is needed to set up seed dormancy during embryo maturation whereas gibberellin (GA) stimulates seed germination. In tomato and Arabidopsis, GA is clearly ...

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

    Microsoft Academic Search

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

    1999-01-01

    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

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

    E-print Network

    Wurtele, Eve Syrkin

    Protocol to Sterilize & Charcoal-Germinate Maize Seeds 1 PROTOCOL TO STERILIZE AND CHARCHOAL plates De-colorizing charcoal (Acros Organics) available from Fisher, Catalog # AC17153-0010 Materials: Autoclaved forceps and spoon (for scooping charcoal) *Prior to germination, autoclave forceps, spoon

  11. Methods toward improving 'Grande Rio 66' pepper seed germination 

    E-print Network

    Rogers, Barbara Anna

    1980-01-01

    ) pepper seed for days 3 through 12 are presented in Table 4. Analysis of variance followed by Duncan's Multiple Range Test showed no significant increases in total germination of chemically treated seeds when compared to the distilled water control... indicated vertically by a-b; by Duncan's Multiple Range Test, 5X. *Indicates days to 50K germination. 23 (80. 55) in gemnination, wheras 2nS04 showed a 1. 0%%u increase in germination (82. 5%) and the distilled water control (81. 5%). These variations...

  12. Comparison of the growth of Escherichia coli O157: H7 and O104: H4 during sprouting and microgreen production from contaminated radish seeds.

    PubMed

    Xiao, Zhenlei; Nou, Xiangwu; Luo, Yanguang; Wang, Qin

    2014-12-01

    Both sprouts and microgreens are popular tender produce items, typically grown and harvested in indoor facilities which allow a higher degree of control compared to open field production. While sprouts, which have frequently been implicated in foodborne illness outbreaks, are the subject of numerous national and international standards for their production and distribution, there is a lack of data pertaining to the microbiological safety of microgreens. In this study, sprouts and microgreens were produced from radish seeds inoculated with Escherichia coli O157: H7 or O104: H4 and E. coli populations on the harvested products compared to assess the potentials of product contamination from contaminated seeds during sprouting and microgreen production. Both E. coli O157:H7 and O104:H4 grew rapidly during sprouting, reaching levels of 5.8-8.1 log cfu/g and 5.2-7.3 log cfu/g, respectively, depending on the initial inoculation levels of the seeds (1.5-4.6 log cfu/g and 0.8-4.3 log cfu/g on radish seeds, respectively). In comparison, E. coli O157:H7 and O104:H4 populations on harvested microgreens ranged from 0.8 to 4.5 log cfu/g and from 0.6 to 4.0 log cfu/g, respectively. Although harvested microgreens carried significantly less (P < 0.001) E. coli than sprouts germinated from seeds inoculated at the same levels, proliferation of E. coli O157:H7 and O104:H4 occurred during both sprouting and microgreen growth. PMID:25084646

  13. Physiological and biochemical metabolism of germinating broccoli seeds and sprouts.

    PubMed

    Gu, Yingjuan; Guo, Qianghui; Zhang, Liang; Chen, Zhigang; Han, Yongbin; Gu, Zhenxin

    2012-01-11

    Changes in physiological and biochemical metabolism as well as glucoraphanin and sulforaphane contents of germinating broccoli seeds and sprouts were investigated in this study. Sprout length, root length, and fresh weight increased with germination time. Dry weight varied from 2.5 to 3.0 mg per sprout. A rapid increase in respiratory rate of sprouts occurred between 24 and 36 h of germination and then stayed at a high level. HPLC analysis found that glucoraphanin content increased at the early stage (0-12 h) of germination, decreased to a low value of 3.02 mg/g at 48 h, and then reached the highest value of 6.30 mg/g at 72 h of germination. Sulforaphane content decreased dramatically during the first day of germination, then increased slowly, and reached a high value of 3.38 mg/g at 48 h before declining again. PMID:22142148

  14. TISSUE-SPECIFIC TRANSCRIPTION FACTORS EXPRESSED IN GERMINATING ARABIDOPSIS SEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multiple regulatory protein genes expressed in germinating Arabidopsis seeds were identified by screening Arabidopsis enhancer-trap lines (Thomas Jack lines, 1,130 pools of 10 lines, CS31086, Arabidopsis Biological Resource Center) for '-glucuronidase (GUS) reporter gene expression in seeds. The ide...

  15. Seed germination ecology of the aquatic winter annual Hottonia inflata

    Microsoft Academic Search

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

    1996-01-01

    Freshly collected seeds of Hottonia inflata were buried in soil under flooded conditions in May 1991 and exposed to seasonal temperature cycles for 39 months. Seeds were exhumed at 1-, 2- or 4-month intervals and tested for germination on moist sand in light (14 h daily photoperiod) and in continuous darkness under 1212 h thermoperiods of 156, 2010, 2515, 3015

  16. In vitro seed germination and seedling propagation in Campanula spp

    Microsoft Academic Search

    Ludovica Seglie; Valentina Scariot; Federica Larcher; Marco Devecchi; Paola Maria Chiavazza

    2012-01-01

    The present research investigated in vitro seed germination and seedling multiplication methods to preserve and introduce new naturalized valuable Campanula species to the floriculture markets. Populations of Campanula barbata L., Campanula latifolia L., Campanula rapunculoides L., Campanula spicata L., and Campanula trachelium L. from various sites in northern Italy were considered in this study. Seeds were sown on half-strength Murashige and

  17. In vitro seed germination and seedling propagation in Campanula spp

    Microsoft Academic Search

    Ludovica Seglie; Valentina Scariot; Federica Larcher; Marco Devecchi; Paola Maria Chiavazza

    2011-01-01

    The present research investigated in vitro seed germination and seedling multiplication methods to preserve and introduce new naturalized valuable Campanula species to the floriculture markets. Populations of Campanula barbata L., Campanula latifolia L., Campanula rapunculoides L., Campanula spicata L., and Campanula trachelium L. from various sites in northern Italy were considered in this study. Seeds were sown on half-strength Murashige and

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

    PubMed

    Franzese, J; Ghermandi, L

    2011-11-01

    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

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

    Microsoft Academic Search

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

    2004-01-01

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

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

    SciTech Connect

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

    1995-12-31

    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.

  1. Evolution of nutrient ingredients in tartary buckwheat seeds during germination.

    PubMed

    Yiming, Zhou; Hong, Wang; Linlin, Cui; Xiaoli, Zhou; Wen, Tang; Xinli, Song

    2015-11-01

    Evolution of nutrient components and the antioxidative activity of seed sprouts of tartary buckwheat (Fagopyrum tataricum L. Gaertn) were investigated in the course of germination. Results showed that the contents of total flavonoids increased with germination time and leveled off after the third germination day with the changing trend of rutin and quercetin opposite to each other. The decrease of total protein and total sugar contents in the germinated seeds was accompanied respectively by an increase of amino acid and reducing sugar contents. The contents of vitamin C (Vc) and B1(VB1) exhibited a minimum with no appreciable changes found for vitamin B2 (VB2) and B6 (VB6). The contents of total chlorophyll, chlorophyll A and B all exhibited a maximum on the fifth germination day. The contents of fatty acids had no regular changing trend with germination time. The free radical-scavenging activities of the seeds increased with germination time and were caused by an increase in their antioxidative activity. PMID:25976817

  2. Seed germination of five mountain steppe species of Central Asia

    Microsoft Academic Search

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

    2007-01-01

    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

  3. Metabolism of carbohydrate and lipid reserves in germinated cotton seeds

    Microsoft Academic Search

    Diane C. Doman; John C. Walker; Richard N. Trelease; Brandon d. Moore

    1982-01-01

    Utilization of reserve lipid and carbohydrates during germination (0–12 h) and postgerminative growth (12–48 h) was studied in cotton (Gossypium hirsutum L.) seedlings. Raffinose and stachyose were utilized during the germination period and early growth; mobilization was associated with a-galactosidase (EC 3.2.1.22) activity. Results from pulse-chase experiments with [3H]raffinose supplied exogenously to 4-h soaked seeds indicated that raffinose-derived catabolites contributed

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

    Microsoft Academic Search

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

    2001-01-01

    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

  5. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false Germination of vegetable seed in containers of 1 pound or less. 201.29 Section...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  6. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false Germination of vegetable seed in containers of 1 pound or less. 201.29 Section...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

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

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 false Germination of vegetable seed in containers of 1 pound or less. 201.29 Section...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  8. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Germination of vegetable seed in containers of 1 pound or less. 201.29 Section...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  9. 7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 false Germination of vegetable seed in containers of 1 pound or less. 201.29 Section...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

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

    E-print Network

    Vuik, Kees

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

  11. Cottonseed malate synthase : biogenesis in maturing and germinated seeds.

    PubMed

    Turley, R B; Trelease, R N

    1987-08-01

    The activity of malate synthase (MS) (EC 4.1.3.2) appears and increases during cotton (Gossypium hirsutum L.) seed maturation, persists through desiccation and imbibition, then increases again following germination. The research reported herein is a comparative study of the synthesis and acquisition of MS into glyoxysomes as they occur in maturing and germinated seeds. Rate-zonal centrifugation of cotyledon extracts revealed that the 5 Svedberg unit (S) cytosolic form of MS was the only form present at 42 days postanthesis (DPA) when activity was first detectable. At later stages (48 DPA, 0 day, 26 hours, and 48 hours), both the 5S and glyoxysomal 20S forms were present, with the 20S form becoming much more prevalent. Western blot analyses revealed that no other form(s) of MS were present in the phosphate-buffered gradients, and that 5S and 20S forms had the same subunit molecular weight in maturing and germinated seeds. Comparisons of radiospecific activity of MS immunoprecipitates following in vivo labeling with [(35)S]methionine for varying time intervals provided strong evidence for a 5S-precursor to 20S-product relationship during both seed maturation and seedling growth. Comparisons of MS labeled in vivo and in vitro in wheat germ and rabbit reticulocyte lysates programmed with poly(A)(+)RNA (from maturing and germinated seeds) revealed no detectable differences in subunit molecular weights. These results reinforced our other data indicating that MS was synthesized in the cytosol and acquired by glyoxysomes in both maturing and germinated cotton seeds without involvement of an intervening aggregate pool in the endoplasmic reticulum, or via processing of a cleavable precursor molecule. MS was translated from poly(A)(+)RNA extracted from 28 DPA cotton seeds. This was nearly 2 weeks before MS activity or protein was detected in vivo. This finding invites further study on the regulation of RNA transcripts during maturation. PMID:16665609

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

    E-print Network

    Paris-Sud XI, Université de

    Germination of Cynara seeds ; effect of light and temperature and function of the endosperm Yehuda SUMMARY The germination behaviour of globe artichoke (Cynara scolymus L.) seeds is described. Germination was par- tially inhibited by light and/or by elevated temperatures (30°-35° C). At 30 °C seeds exuded

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

    Microsoft Academic Search

    Kevin J. Rice; Andrew R. Dyer

    2001-01-01

    In annual plants, increased competitive advantage has often been attributed to rapid germination and early establishment. In contrast, many annual species exhibit some degree of delayed germination (i.e., seed dormancy) that results in the formation of age structure within the seed population. Delayed germination can be an effective bet-hedging strategy in variable or unpredictable environments as a seed bank can

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

    Microsoft Academic Search

    Kevin J. Rice; Andrew R. Dyer

    2001-01-01

    In annual plants, increased competitive advantage has often been attributed to rapid germination and early es- tablishment. In contrast, many annual species exhibit some degree of delayed germination (i.e., seed dormancy) that results in the formation of age structure within the seed population. Delayed germination can be an effective bet-hedging strategy in variable or unpredictable environments as a seed bank

  15. COMPARATIVE EFFECT OF NaCl AND SEAWATER ON SEED GERMINATION OF LIMONIUM STOCKSII

    Microsoft Academic Search

    SABAHAT ZIA; M. AJMAL KHAN

    Limonium stocksii (Boiss.) O. Kuntze, a secreting perennial in the family Plumbaginaceae, is widely distributed in the coastal marshes of Karachi, Pakistan. We are reporting here the effect of seawater and NaCl on the seed germination of L. stocksii both under a 12 h photoperiod and in complete darkness. Seed germination decreased with increase in salinity and few seeds germinated

  16. Proteomic analysis of seed germination under salt stress in soybeans

    Microsoft Academic Search

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

    2011-01-01

    Soybean (Glycine max (L.) Merrill) is a salt-sensitive crop, and its production is severely affected by saline soils. Therefore, the response\\u000a of soybean seeds to salt stress during germination was investigated at both physiological and proteomic levels. The salt-tolerant\\u000a cultivar Lee68 and salt-sensitive cultivar N2899 were exposed to 100 mmol\\/L NaCl until radicle protrusion from the seed coat.\\u000a In both

  17. Ontogeny of Cotton Seeds: Gametogenesis, Embryogenesis, Germination, and Seedling Growth

    Microsoft Academic Search

    Rickie B. Turley; Kent D. Chapman

    Production of a viable seed is of paramount importance to the survival of a plant species. Many plants, including cotton,\\u000a amass large reserves of storage protein and oil in their seeds (oilseeds) to use during dormancy, germination, and seedling\\u000a growth. These reserves are mobilized after imbibition when environmental conditions are favorable for growth. Due to their\\u000a rich supply of protein

  18. Ecophysiology of seed germination in Mediterranean geophytes. 1. Muscari spp

    Microsoft Academic Search

    Maria A. Doussi

    2002-01-01

    Ecophysiological aspects of seed germination were investigated in four Mediterranean geophytes of the genus Muscari (Liliaceae): M. comosum (tassel hyacinth), M. neglectum (common grape hyacinth), M. commutatum and M. weissii. Experiments were performed at constant temperatures in the dark and under temperature and light conditions simulating those prevailing in nature during November-January, i.e. well into the rainy season of the

  19. A microcalorimetric study of Chenopodium quinoa Willd. seed germination

    Microsoft Academic Search

    E. Elizabeth Sigstad; Fernando E Prado

    1999-01-01

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

  20. Biphasic Fluence Response Curves for Induction of Seed Germination 1

    PubMed Central

    Kendrick, Richard E.; Cone, John W.

    1985-01-01

    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

  1. Interspecific Variations in Seed Germination of Corylopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was initiated to investigate the difference in germination pattern between C. coreana Uyeki and C. sinensis var. calvescens Rehder & E. H. Wilson responding to a warm (WS) and cold stratification (CS), and to study the effect of different WS temperatures interacting with different duratio...

  2. Effect of cadmium on germination, amylases and rate of respiration of germinating pea seeds

    Microsoft Academic Search

    L. K. Chugh; S. K. Sawhney

    1996-01-01

    Growth of embryonic axis of germinating pea seeds (Pisum sativum cv. Bonneville) was significantly inhibited by as low as 0.25 mM cadmium and the elongation of the radicle was affected more severely than that of the plumule. Total amylolytic activity, as well as activities of ?- and ?-amylases, diminished progressively with increasing concentrations of the metal in the media. The

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

    PubMed Central

    Sinkkonen, Aki

    2006-01-01

    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

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

    PubMed Central

    Sinkkonen, Aki

    2005-01-01

    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

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

    NASA Astrophysics Data System (ADS)

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

    2013-11-01

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

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

    NASA Astrophysics Data System (ADS)

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

    2012-01-01

    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.

  7. Proteomic analysis of lettuce seed germination and thermoinhibition by sampling of individual seeds at germination and removal of storage proteins by polyethylene glycol fractionation.

    PubMed

    Wang, Wei-Qing; Song, Bin-Yan; Deng, Zhi-Jun; Wang, Yue; Liu, Shu-Jun; Møller, Ian Max; Song, Song-Quan

    2015-04-01

    Germination and thermoinhibition in lettuce (Lactuca sativa 'Jianyexianfeng No. 1') seeds were investigated by a proteomic comparison among dry seeds, germinated seeds at 15°C, at 15°C after imbibition at 25°C for 48 h, or at 25°C in KNO3 (all sampled individually at germination), and ungerminated seeds at 25°C, a thermoinhibitory temperature. Before two-dimensional gel electrophoresis analysis, storage proteins (greater than 50% of total extractable protein) were removed by polyethylene glycol precipitation, which significantly improved the detection of less abundant proteins on two-dimensional gels. A total of 108 protein spots were identified to change more than 2-fold (P<0.05) in abundance in at least one germination treatment. Nineteen proteins increasing and one protein decreasing in abundance during germination had higher abundance in germinated 15°C, 15°C after imbibition at 25°C for 48 h, and 25°C in KNO3 seeds than in ungerminated 25°C seeds. Gene expression of 12 of those proteins correlated well with the protein accumulation. Methionine metabolism, ethylene production, lipid mobilization, cell elongation, and detoxification of aldehydes were revealed to be potentially related to lettuce seed germination and thermoinhibition. Accumulation of three proteins and expression of five genes participating in the mevalonate (MVA) pathway of isoprenoid biosynthesis correlated positively with seed germinability. Inhibition of this pathway by lovastatin delayed seed germination and increased the sensitivity of germination to abscisic acid. MVA pathway-derived products, cytokinins, partially reversed the lovastatin inhibition of germination and released seed thermoinhibition at 25°C. We conclude that the MVA pathway for isoprenoid biosynthesis is involved in lettuce seed germination and thermoinhibition. PMID:25736209

  8. Allelopathic interactions of resident tussock grassland species on germination of oversown seed

    Microsoft Academic Search

    D. Scott

    1975-01-01

    Effects of freeze-dried shoot and fresh root-soil materials from several tussock grassland species on the germination of seed of white clover, red clover, lucerne, lotus, browntop, chewings fescue, and cocksfoot were compared.Most materials markedly depressed germination of grass seed, but promoted or depressed germination of legume seed.Raoulia spp. promoted germination most, and Trifolium spp., Anthoxanthum odoratum, and Poa laevis depressed

  9. Effect of day length on germination of seeds collected in Alaska

    USGS Publications Warehouse

    Densmore, R.V.

    1997-01-01

    Day length control can effectively limit seed germination to favorable seasons, but this phenomenon has been studied in relatively few wild plants. I tested species from interior Alaska for day length control of germination under controlled conditions, and I also monitored germination phenology in natural habitats. Unstratified and cold-stratified seeds were germinated on short (13 h) and long (22 h) day length and in the dark at constant and alternating temperatures. On long day length, unstratified Ledum decumbens and Saxifraga tricuspidata seeds germinated from 5??C to 20??C, but on short day length few or no seeds germinated at 5??C and 10??C and germination was reduced at higher temperatures. Unstratified seeds of Diapensia lapponica and Chamaedaphne calyculata germinated only at 15??C and 20??C on long day length, and short day length completely inhibited germination. Cold stratification widened the temperature range for germination on both long and short day lengths, but germination was still lower on short than long day length. Germination phenology in natural habitats was consistent with germination in controlled conditions. In these species, short day length and low temperatures interact to inhibit germination in the fall. After overwintering, seeds germinate in the spring at low temperatures and on long day lengths. The inhibitory effect of short day length is not important in the spring because day length is already long at snowmelt.

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

    Microsoft Academic Search

    L. M. Vleeshouwers; H. J. Bouwmeester

    2001-01-01

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

  11. GERMINATION OF STYRAX JAPONICUS SEEDS AS INFLUENCED BY STORAGE AND SOWING CONDITIONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluated the effect of storage and sowing conditions on seed germination of Styrax japonicus Sieb. et. Zucc, an ornamental tree with seeds that exhibit double dormancy. The germination of freshly harvested seeds was compared with seeds that had been stored dry at 20C for a year before s...

  12. Effects of gut passage on seed germination: do experiments answer the questions they ask?

    Microsoft Academic Search

    I. A. SAMUELS; D. J. LEVEY

    2005-01-01

    Summary 1. Frugivorous vertebrates may affect plant fitness by dispersing seeds to sites favour- able for establishment and by passing seeds through their gut, thereby altering germi- nation patterns. Although gut passage can inhibit germination, most studies have found that it improves germination rate and\\/or success. 2. However, studies that compare seeds passed through a gut to seeds directly removed

  13. Carbonhydrate Content and Root Growth in Seeds Germinated Under Salt Stress: Implications for Seed Conditioning

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Sugars and sugar alcohols have well documented roles in salt tolerance in whole plants and maturing seeds. Less is known, however, about possible effects of these compounds during germination. Seeds from mannitol-accumulating salt-tolerant celery [Apium graveloens L. var. dulce (P. Mill.) DC], non...

  14. Seed after-ripening and dormancy determine adult life history independently of germination timing.

    PubMed

    de Casas, Rafael Rubio; Kovach, Katherine; Dittmar, Emily; Barua, Deepak; Barco, Brenden; Donohue, Kathleen

    2012-05-01

    Seed dormancy can affect life history through its effects on germination time. Here, we investigate its influence on life history beyond the timing of germination. • We used the response of Arabidopsis thaliana to chilling at the germination and flowering stages to test the following: how seed dormancy affects germination responses to the environment; whether variation in dormancy affects adult phenology independently of germination time; and whether environmental cues experienced by dormant seeds have an effect on adult life history. • Dormancy conditioned the germination response to low temperatures, such that prolonged periods of chilling induced dormancy in nondormant seeds, but stimulated germination in dormant seeds. The alleviation of dormancy through after-ripening was associated with earlier flowering, independent of germination date. Experimental dormancy manipulations showed that prolonged chilling at the seed stage always induced earlier flowering, regardless of seed dormancy. Surprisingly, this effect of seed chilling on flowering time was observed even when low temperatures did not induce germination. • In summary, seed dormancy influences flowering time and hence life history independent of its effects on germination timing. We conclude that the seed stage has a pronounced effect on life history, the influence of which goes well beyond the timing of germination. PMID:22404637

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

    PubMed

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

    2007-04-01

    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

  16. Seed germination of Stenocereus thurberi (Cactaceae) under different solar irradiation levels

    Microsoft Academic Search

    H Nolasco; F Vega-Villasante; A Diaz-Rondero

    1997-01-01

    Germination ofStenocereus thurberiseeds was evaluated under different conditions of solar irradiation and humidity. Seed germination increased under higher humidity and low solar irradiation which provided cooler temperatures and higher water availability. Seedlings were also greener and more turgid under these conditions. Increased solar irradiation reduced seed germination and decreased seedling size and water content. The results of this study support

  17. Seed Germination and Vegetative Propagation of Seneca Snakeroot (Polygala senega L.)

    E-print Network

    Kenkel, Norm

    of the plant hormone gibberellic acid (10-20 mg/L) to the moist filter paper. The germination rate should be 80#12;#12;#12;#12;#12;#12;#12;#12;Seed Germination and Vegetative Propagation of Seneca Snakeroot (Polygala senega L.) SEED GERMINATION WITH COLD STRATIFICATION 1. In moist sand, cold-stratify (at 3º

  18. Germination of grain amaranth ( Amaranthus hypochondriacus × A. hybridus): effects of seed quality, temperature, light, and pesticides

    Microsoft Academic Search

    W. Aufhammer; D. Czuczorova; H.-P. Kaul; M. Kruse

    1998-01-01

    Seven experiments were conducted in incubators to determine the effects of several factors on the germination of two amaranth cultivars. Investigated factors were year of harvest, crop type of the mother plant, seed position on the mother plant, stage of maturity, temperature, light, and seed dressing. Percentage germination and germination speed were recorded.Most effects appeared in interaction with cultivars. Percentage

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

    Microsoft Academic Search

    Moshe Agami; Yoav Waisel

    1986-01-01

    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

  20. THE ROLE OF THE SLEEPY1 (SLY1) F-BOX GENE IN GA REGULATION OF SEED GERMINATION IN ARABIDOPSIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    17th International Conference on Arabidopsis Research, June 28-July 2, 2006, Madison, WI. Abstract #378. Seed germination is a complex developmental process regulated by phytohormones. The phytohormone abscisic acid (ABA) inhibits seed germination, whereas gibberellin (GA) stimulates seed germinat...

  1. The effect of seed source, light during germination, and cold-moist stratification on seed germination in three species of Echinacea for organic production.

    PubMed

    Romero, Fredy R; Delate, Kathleen; Hannapel, David J

    2005-10-01

    Organic production of one of the most popular botanical supplements, Echinacea, continues to expand in the U.S. Echinacea seeds typically show a high degree of dormancy that can be broken by ethephon or gibberelic acid (GA), but these methods are currently disallowed in organic production. In order to determine the efficacy of non-chemical seed treatments, we evaluated the effect of varying seed source and supplying light, with and without cold-moist stratification, on seed germination of the three most important medicinal species of Echinacea, E. angustifolia DC, E. purpurea (L) Moench, and E. pallida (Nutt.) Nutt. Treatments included cold-moist stratification under 24 h light, 24 h dark, and 16/8 h light/dark to break seed dormancy. We found that germination was greater in the E. purpurea and E. pallida seeds from a commercial organic seed source compared to a public germplasm source. When seeds were not cold-moist stratified, 16-24 h light increased germination in E. angustifolia only. Echinacea angustifolia, E. purpurea, and E. pallida seeds that were cold-moist stratified under 16-24 h of light for 4 wk had a significantly greater percentage and rate of germination compared to seeds germinated in the dark. Therefore, cold-moist stratification under light conditions is recommended as a method to break seed dormancy and increase germination rates in organic production of Echinacea. PMID:17160141

  2. The effect of seed source, light during germination, and cold-moist stratification on seed germination in three species of Echinacea for organic production

    PubMed Central

    Romero, Fredy R.; Delate, Kathleen; Hannapel, David J.

    2006-01-01

    Organic production of one of the most popular botanical supplements, Echinacea, continues to expand in the U.S. Echinacea seeds typically show a high degree of dormancy that can be broken by ethephon or gibberelic acid (GA), but these methods are currently disallowed in organic production. In order to determine the efficacy of non-chemical seed treatments, we evaluated the effect of varying seed source and supplying light, with and without cold-moist stratification, on seed germination of the three most important medicinal species of Echinacea, E. angustifolia DC, E. purpurea (L) Moench, and E. pallida (Nutt.) Nutt. Treatments included cold-moist stratification under 24 h light, 24 h dark, and 16/8 h light/dark to break seed dormancy. We found that germination was greater in the E. purpurea and E. pallida seeds from a commercial organic seed source compared to a public germplasm source. When seeds were not cold-moist stratified, 16–24 h light increased germination in E. angustifolia only. Echinacea angustifolia, E. purpurea, and E. pallida seeds that were cold-moist stratified under 16–24 h of light for 4 wk had a significantly greater percentage and rate of germination compared to seeds germinated in the dark. Therefore, cold-moist stratification under light conditions is recommended as a method to break seed dormancy and increase germination rates in organic production of Echinacea. PMID:17160141

  3. Distribution of fatty acids during germination of soybean seeds

    Microsoft Academic Search

    A. C. Joshi; B. K. Chopra; L. C. Collins; V. M

    1973-01-01

    Gas chromatographic determination of the fatty acids in the seeds of soybean (Glycine max) showed mainly linoleic, oleic and palmitic acids with linoleic acid being the major component. Changes in the distribution\\u000a of fatty acids were measured during germination in the cotyledons and roots. A decrease in palmitic and oleic acids was observed\\u000a in the cotyledons from 6 to 12

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

    E-print Network

    Yoon, Beyoung-Han

    1995-01-01

    various salt solutions at defined osmotic potentials as effective priming treatment for improving germination and emergence of pansy seed at high temperatures. the second objectives was to compare respiration rates during germination for primed...

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

    E-print Network

    Samfield, Dina Margaret

    1988-01-01

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

  6. Gibberellin Biosynthesis and Response during Arabidopsis Seed GerminationW?

    PubMed Central

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

    2003-01-01

    The hormone-mediated control of plant growth and development involves both synthesis and response. Previous studies have shown that gibberellin (GA) plays an essential role in Arabidopsis seed germination. To learn how GA stimulates seed germination, we performed comprehensive analyses of GA biosynthesis and response using gas chromatography–mass spectrometry and oligonucleotide-based DNA microarray analysis. In addition, spatial correlations between GA biosynthesis and response were assessed by in situ hybridization. We identified a number of transcripts, the abundance of which is modulated upon exposure to exogenous GA. A subset of these GA-regulated genes was expressed in accordance with an increase in endogenous active GA levels, which occurs just before radicle emergence. The GA-responsive genes identified include those responsible for synthesis, transport, and signaling of other hormones, suggesting the presence of uncharacterized crosstalk between GA and other hormones. In situ hybridization analysis demonstrated that the expression of GA-responsive genes is not restricted to the predicted site of GA biosynthesis, suggesting that GA itself, or GA signals, is transmitted across different cell types during Arabidopsis seed germination. PMID:12837949

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

    E-print Network

    Fedigan, Linda M.

    Effects of Gut Passage, Feces, and Seed Handling on Latency and Rate of Germination in Seeds, University of Calgary, Calgary, AB, T2N-1N4, Canada KEY WORDS seed dispersal; Cebus capucinus; Santa Rosa of primary seed dispersal by animals is the quality of seed dispersal (Schupp: Plant Ecol 107/108 [1993] 15

  8. EFFECTS OF PREGERMINATION TREATMENTS, DESICCATION AND STORAGE TEMPERATURE ON GERMINATION OF CARISSA EDULIS, VANGUERIA MADAGASCARIENSIS AND XIMENIA AMERICANA SEEDS

    Microsoft Academic Search

    N. T. Maar; M. Karachi; J. O. Ahenda

    MAARA, N. T., KARACHI, M. & AHENDA, J. O. 2006. Effects of pre-germination treatments, desiccation and storage temperature on germination of Carissa edulis, Vangueria madagascariensis and Ximenia americana seeds. Effects of seed pre-germination treatments, desiccation, storage temperature and duration of storage on germination of freshly harvested Carissa edulis, Vangueria madagascariensis and Ximenia americana seeds were investigated in three experiments in

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

    E-print Network

    Leubner, Gerhard

    Water Uptake and Distribution in Germinating Tobacco Seeds Investigated in Vivo by Nuclear Magnetic of germinating tobacco (Nicotiana tabacum) seeds was studied spatially and temporally by in vivo 1 H is inhomogeneous. The micropylar seed end is the major entry point of water. The micropylar endosperm

  10. Effect of sea salt and l-ascorbic acid on the seed germination of halophytes

    Microsoft Academic Search

    M. Ajmal Khan; M. Zaheer Ahmed; A. Hameed

    2006-01-01

    Effects of l-ascorbic acid and sea salt solutions on the seed germination of Atriplex stocksii, Arthrocnemum macrostachyum, Haloxylon stocksii, Suaeda fruticosa, Desmostachya bipinnata and Aeluropus lagopoides were studied. Increasing concentration of sea salt inhibited seed germination of all species with comparatively more adverse effect on A. stocksii and S. fruticosa than others. Pretreatment of seeds with l-ascorbic acid alleviated the

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  12. Effect of Salt Stress, Proline, and Polyamines on Seed Germination of Opuntia streptacantha

    Microsoft Academic Search

    Ana E. Ochoa-Alfaro; Claudia O. Silva-Ortega; Alicia Becerra-Flora; Joel Flores-Rivas; Juan F. Jiménez-Bremont

    In this study we conducted experiments in order to determine whether polyamines (putrescine, spermidine, and spermine) and proline treatments help to break seed dormancy of Opuntia streptacantha and also if they facilitate seed germination under salt stress. The results showed that 1mM proline stimulated a better germination percentage as compared to untreated seeds, although the difference was not statistically significant.

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

    Microsoft Academic Search

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

    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

  14. Seed ecology and germination treatments in Magnolia dealbata: An endangered species

    Microsoft Academic Search

    Juan Corral-Aguirre; Lázaro Rafael Sánchez-Velásquez

    2006-01-01

    Magnolia dealbata is a deciduous tree species in danger of extinction. Seed ecology data and successful germination treatments are important for conservation and species reintroduction programs. This study reports about seed ecology and germination treatments of M. dealbata Zucc. The results showed that the seeds, influence of vertebrates excluded, persisted viable after 1 year, suggesting the presence of a semi-persistent

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

    PubMed

    Siddiqui, Manzer H; Al-Whaibi, Mohamed H

    2014-01-01

    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

  16. Abscisic acid inhibits germination of mature Arabidopsis seeds by limiting the availability of energy and nutrients

    Microsoft Academic Search

    Alejandro Garciarrubio; Juan P. Legaria; Alejandra A. Covarrubias

    1997-01-01

    .   The addition of abscisic acid (ABA) to mature non-dormant seeds inhibits their germination. This effect of ABA might be related\\u000a to its natural function as an endogenous inhibitor of precocious germination during seed formation. In this work, we studied\\u000a how ABA affects the germination of mature seeds and the growth of nascent seedlings of Arabidopsisthaliana (L.) Heynh. Our findings

  17. Effect of water stress and gibberellic acid on germination of flax, sesame and onion seeds

    Microsoft Academic Search

    M. M. Heikal; M. A. Shaddad; A. M. Ahmed

    1982-01-01

    The effects of different osmotic stresses (from 0 to –8× 105 Pa) obtained with NaC or polyethylene glycol 6000 solutions on the germination of flax, sesame and onion seeds were investigated.\\u000a The effect of presoaking with gibberellic acid (GA3) on the germination of the above mentioned seeds was also studied.\\u000a \\u000a It was found that the rate of seed germination and

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

    Microsoft Academic Search

    Wenbo Jiang; Diqiu Yu

    2009-01-01

    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

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

    Microsoft Academic Search

    Sachiko Araki; Izumi Washitani

    2000-01-01

    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

  20. Reprinted by kind permission of the publishers of Seed Science and Technology: Treatment of Eucalyptus Seed to Maximise Germination

    Microsoft Academic Search

    D. G. M. Donald; J. E. Lundquist

    1988-01-01

    An abundant and diverse mycoflora was found on the seed surface of Eucalyptus cloeziana, E. fastigata, E. fraxinoides, E. grandis, E. macarthurii and E. radiata var. australiana. The fungi inhibited germination in species with high germinative energy. Hot water treatments (50°C), surface treatments (10% sodium hypochlorite and 33,3% hydrogen peroxide) and fungicidal application (Captan) restricted fungal development and increased germinative

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

    PubMed Central

    Bewley, J. Derek; Oaks, Ann

    1980-01-01

    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

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

    Microsoft Academic Search

    Adam S. Davis; Karen A. Renner

    2007-01-01

    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

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

    Microsoft Academic Search

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

    1998-01-01

    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,

  4. GERMINATION PERFORMANCE OF SEQUENTIALLY HARVESTED TOMATO (LYCOPERSICON ESCULENTUM MILL.) SEED LOTS DURING SEED DEVELOPMENT UNDER SALT AND OSMOTIC STRESS

    Microsoft Academic Search

    Mustafa OZCOBAN; Ibrahim DEMIR

    This work concluded that tomato seeds harvested 70 days after anthesis showed the maximum germination not only under water but also salt stress. Seeds harvested earlier or later were more sensitive to stress at germinations. High Ki value of the lots indicated high resistance under stress conditions.

  5. Teaching Through Trade Books: Secrets of Seeds

    NSDL National Science Digital Library

    Emily Morgan

    2009-02-01

    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.

  6. Effect of Light on Seed Germination of Eight Wetland Carex Species

    PubMed Central

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

    2006-01-01

    • 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

  7. Effect on microorganisms of volatile compounds released from germinating seeds.

    PubMed

    Schenck, S; Stotzky, G

    1975-10-01

    Volatile compounds evolved from germinating seeds of slash pine, bean, cabbage, corn, cucumber, and pea were evaluated for their ability to support growth of microorganisms in liquid mineral salts media lacking a carbon source. Growth of eight bacteria was measured turbidimetrically and of six fungi as dry weight of mycelium. Volatiles caused increased growth of Pseudomonas fluorescens, Bacillus cereus, Erwinia carotovora, Agrobacterium tumefaciens, A. radiobacter, Rhizobium japonicum, Mucor mucedo, Fusarium oxysporum f. conglutinans, Trichoderma viride, and Penicillium vermiculatum but not of Sarcina lutea, Serratia marcescens, Chaetomium globosum, or Schizophyllum commune. Spores of Trichoderma viride showed higher germination in the presence of volatiles. Effects on growth were apparent only during the first 3 or 4 days after planting the seeds. Killed or dried seeds had no effect. The volatiles did not support microbial growth in the absence of nitrogen nor did they supply growth factors. Passing volatiles through KMnO4 or hydrazone reduced growth of the bacteria, indicating that oxidizable organic compounds, primarily aldehydes, were the active components. The volatiles were not absorbed by sterile soil, clay minerals, or water, but they were absorbed by non-steril soil and activated charcoal. PMID:1201509

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

    E-print Network

    Gouveia, Sergio

    1994-01-01

    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...

  9. Does Germination Success Differ with Respect to Seed Mass and Germination Season? Experimental Testing of Plant Functional Trait Responses to Grassland Management

    PubMed Central

    Kahmen, S.; Poschlod, P.

    2008-01-01

    Background and Aims Plant functional trait responses to processes such as grassland management have been analysed frequently; however, the scaling-up from individual traits to the outcomes of vegetation dynamics has seldom been tested. In this experiment, germination success was studied with respect to the relationships between grassland management (mowing and grazing), as well as abandonment, and two traits that are relevant for seedling recruitment: seed mass and germination season. On the basis of discussions in the literature and indirect trait analyses in our previous studies, the following hypotheses are proposed: (1) with respect to seed mass, mowing and grazing favour the germination of small seeds, whereas after abandonment the germination success of larger seeds is higher; and (2) with respect to germination season, mowing and grazing favour autumn-germinating seeds, whereas succession promotes spring-germinating seeds. Methods The germination experiment took place in a semi-natural, dry grassland in north-east Germany. Seeds of eight herbaceous species that differ with respect to seed mass and germination season were sown in mown, grazed and abandoned plots. Germination success was documented during the following year. Key Results and Conclusions Contrary to the hypothesis, germination of small seeds was not promoted by mowing or grazing and they germinated relatively more often than expected in the abandoned plots. A relationship between abandonment and gaps of bare soil below the vegetation cover that favour germination of small seeds was likely, but could not be proved statistically. It is possible that the small seeds suffered less from predation. Mowing favoured autumn germination, which could be explained by the removal of biomass in late summer. Contrary to our expectation, there was relatively more spring germination after grazing than after mowing, yet vegetation height was smallest in spring. Generally, germination season was found to be related to the temporal occurrence of favourable light conditions. PMID:18083716

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

    Microsoft Academic Search

    Xiaoshan Wang; Guoqi Zhao; Hongru Gu

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

  11. G Protein Signaling in the Regulation of Rice Seed Germination

    NSDL National Science Digital Library

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

    2005-11-15

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

  12. A Race for Survival: Can Bromus tectorum Seeds Escape Pyrenophora semeniperda-caused Mortality by Germinating Quickly?

    PubMed Central

    Beckstead, Julie; Meyer, Susan E.; Molder, Cherrilyn J.; Smith, Caitlyn

    2007-01-01

    Background and Aims Pathogen–seed interactions may involve a race for seed resources, so that seeds that germinate more quickly, mobilizing reserves, will be more likely to escape seed death than slow-germinating seeds. This race-for-survival hypothesis was tested for the North American seed pathogen Pyrenophora semeniperda on seeds of the annual grass Bromus tectorum, an invasive plant in North America. In this species, the seed germination rate varies as a function of dormancy status; dormant seeds germinate slowly if at all, whereas non-dormant seeds germinate quickly. Methods Three experimental approaches were utilized: (a) artificial inoculations of mature seeds that varied in primary dormancy status and wounding treatment; (b) naturally inoculated undispersed seeds that varied in primary dormancy status; and (c) naturally inoculated seeds from the carry-over seed bank that varied in degree of secondary dormancy, habitat of origin and seed age. Key Results In all three approaches, seeds that germinated slowly were usually killed by the pathogen, whereas seeds that germinated quickly frequently escaped. Pyrenophora semeniperda reduced B. tectorum seed banks. Populations in drier habitats sustained 50 times more seed mortality than a population in a mesic habitat. Older carry-over seeds experienced 30 % more mortality than younger seeds. Conclusions Given the dramatic levels of seed death and the ability of this pathogen to reduce seed carry-over, it is intriguing to consider whether P. semeniperda could be used to control B. tectorum through direct reduction of its seed bank. PMID:17353206

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

    NASA Astrophysics Data System (ADS)

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

    2006-09-01

    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.

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

    SciTech Connect

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

    1994-07-01

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

  15. Pollen viability, pollen germination and pollen tube growth in the biofuel seed crop Jatropha curcas (Euphorbiaceae)

    Microsoft Academic Search

    H. A. Abdelgadir; S. D. Johnson; J. Van Staden

    The fate of pollen and pollen tubes can have a profound effect on fruit and seed production. Experiments were conducted to investigate pollen viability, in vitro pollen germination and in vivo pollen tube growth in the biofuel seed crop Jatropha curcas. It was possible to distinguish between fresh and dead pollen using 2,3,5-triphenyltetrazolium chloride (TTC). Pollen germination was significantly higher

  16. DIACYLGLYCEROL ACYLTRANSFERASE ACTIVITY AND TRIACYLGLYCEROL SYNTHESIS IN GERMINATING CASTOR SEED COTYLEDONS

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  17. Essential role of urease in germination of nitrogen-limited Arabidopsis thaliana seeds

    Microsoft Academic Search

    Laura E. Zonia; Norm E. Stebbins; Joseph Carmine Polacco

    1995-01-01

    In Arabidopsis thaliana, urease transcript levels increased sharply between 2 and 4 d after germination (DAC) and were maintained at maximal levels until at least 8 DAC. Seed urease specific activity declined upon germination but began to increase in seedlings 2 DAC, reaching approximately 75% of seed activity by 8 DAC. Urea levels showed a small transient increase 1 DAC

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

    Microsoft Academic Search

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

    2000-01-01

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

  19. Growth regulators and chemicals stimulate germination of leafy spurge seeds (Euphorbia esula)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study was conducted to survey the effect of various growth regulator and chemical treatments on germination of leafy spurge seeds. Non-treated seeds in this population were nearly fully imbibed in 3 h and display approximately 35% germination in 21 d under the normal alternating temperature of ...

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

    Microsoft Academic Search

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

    1998-01-01

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

  1. RGL2 PROTEIN DOES NOT DISAPPEAR DURING SLY1 MUTANT SEED GERMINATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The SLEEPY1 (SLY1) and RGA-like2 (RGL2) genes play an important role in the regulation of seed germination by GA in Arabidopsis. The control of seed dormancy and germination is critical for plant survival and important for proper stand establishment in crop species. The plant hormone gibberelli...

  2. Soil Texture Involvement in Germination and Emergence of Buried Weed Seeds

    Microsoft Academic Search

    Stefano Benvenuti

    2003-01-01

    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

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

    Microsoft Academic Search

    Karin M. Kettenring; Susan M. Galatowitsch

    2007-01-01

    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

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

    Microsoft Academic Search

    J. E. Drifmeyer; J. C. Zieman

    1979-01-01

    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

  5. Characteristics of seed germination in five non-halophytic Chinese desert shrub species

    Microsoft Academic Search

    Kazuo Tobe; Liping Zhang; Guoyu Yu Qiu; Hideyuki Shimizu; Kenji Omasa

    2001-01-01

    The effects of temperature, NaCl, and polyethylene glycol (PEG)-6000 on the seed germination of five non-halophytic Chinese desert shrub species were investigated. The minimum temperature of germination was 10°C for all species, and the maximum temperature varied among species from 25 to 35°C. Isotonic solutions of NaCl and PEG caused different effects on seed germination in all five species. When

  6. PHYTOTOXICITY OF OIL SHALE SEMICOKE AND ITS AQUEOUS EXTRACTS: A STUDY BY SEED GERMINATION BIOASSAY

    Microsoft Academic Search

    H. RAAVE; S. KAPAK; K. ORUPÕLD

    2007-01-01

    Phytotoxicity of oil shale semi-coke has been studied by germination bioassay. Timothy (Phleum pratense) seeds were germinated on solid semi- coke and in its water extracts. Fresh semi-coke completely blocked seed germination but weathering significantly decreased its inhibition effect. The inhibitory effect of aqueous extracts was less than that of solid semi-coke, and it decreased as the liquid-to-solid ratio used

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

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false Germination of vegetable seed in containers of more than 1 pound. 201.29a ...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  8. 7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 2014-01-01 false Germination of vegetable seed in containers of more than 1 pound. 201.29a ...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  9. 7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 2010-01-01 false Germination of vegetable seed in containers of more than 1 pound. 201.29a ...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  10. 7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 2012-01-01 false Germination of vegetable seed in containers of more than 1 pound. 201.29a ...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  11. 7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 2011-01-01 false Germination of vegetable seed in containers of more than 1 pound. 201.29a ...DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds §...

  12. EFFECTS OF SALT AND WATER STRESS ON THE GERMINATION OF CHENOPODIUM GLAUCUM L., SEED

    Microsoft Academic Search

    DEYU DUAN; XIAOJING LIU; M. AJMAL KHAN; BILQUEES GUL

    Effect of salts (Na2SO4, Na2CO3, MgSO4, NaCl, MgCl2), soil extract and polyethylene glycol (PEG-6000) on the germination of Chenopodium glaucum L., seed was studied. Maximum germination was obtained in distilled water. Germination decreased with increase in salinity. The inhibition of germination by salt solutions was in the order of MgCl2 > Na2SO4 > Na2CO3 > NaCl > Soil extract >

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

    Microsoft Academic Search

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

    2002-01-01

    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

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

    E-print Network

    Rice, Kevin

    Seed aging, delayed germination and reduced competitive ability in Bromus tectorum Kevin J. Rice1 pro- duced seed from meadow steppe and sagebrush steppe populations of an annual grass (Bromus tectorum) to in- vestigate the importance of seed age on seedling vigor and competitive ability. Aged seed

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

    PubMed Central

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

    2014-01-01

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

  16. Only seed size matters for germination in different populations of the dimorphic Tragopogon pratensis subsp. pratensis (Asteraceae).

    PubMed

    van Mölken, Tamara; Jorritsma-Wienk, Linda D; van Hoek, Paul H W; de Kroon, Hans

    2005-03-01

    Many studies have focused on the ecology of seed dimorphism, the production of two seed types by a single plant. Morphology and seed size are usually correlated, but how morphology affects germination percentage and seedling growth is poorly understood. Here we explicitly separate these effects for nine populations of the dimorphic species Tragopogon pratensis subsp. pratensis. Larger seeds yielded higher germination percentages, yet seed morphology had no additional direct effect on germination. Neither seed size nor seed morphology affected seedling growth. Neither germination nor seedling growth varied among populations, but seed head varied significantly. Results show that germination is mainly controlled by seed size rather than by seed morphology. This study is one of the few to distinguish explicitly between seed size and seed morphology effects on ecological characteristics and suggests that seed dimorphism may exert its ecological effects predominantly through its correlated size. PMID:21652419

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

    PubMed Central

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

    2014-01-01

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

  18. Arabidopsis Seed Development and Germination Is Associated with Temporally Distinct Metabolic Switches1[W

    PubMed Central

    Fait, Aaron; Angelovici, Ruthie; Less, Hadar; Ohad, Itzhak; Urbanczyk-Wochniak, Ewa; Fernie, Alisdair R.; Galili, Gad

    2006-01-01

    While the metabolic networks in developing seeds during the period of reserve accumulation have been extensively characterized, much less is known about those present during seed desiccation and subsequent germination. Here we utilized metabolite profiling, in conjunction with selective mRNA and physiological profiling to characterize Arabidopsis (Arabidopsis thaliana) seeds throughout development and germination. Seed maturation was associated with a significant reduction of most sugars, organic acids, and amino acids, suggesting their efficient incorporation into storage reserves. The transition from reserve accumulation to seed desiccation was associated with a major metabolic switch, resulting in the accumulation of distinct sugars, organic acids, nitrogen-rich amino acids, and shikimate-derived metabolites. In contrast, seed vernalization was associated with a decrease in the content of several of the metabolic intermediates accumulated during seed desiccation, implying that these intermediates might support the metabolic reorganization needed for seed germination. Concomitantly, the levels of other metabolites significantly increased during vernalization and were boosted further during germination sensu stricto, implying their importance for germination and seedling establishment. The metabolic switches during seed maturation and germination were also associated with distinct patterns of expression of genes encoding metabolism-associated gene products, as determined by semiquantitative reverse transcription-polymerase chain reaction and analysis of publicly available microarray data. When taken together our results provide a comprehensive picture of the coordinated changes in primary metabolism that underlie seed development and germination in Arabidopsis. They furthermore imply that the metabolic preparation for germination and efficient seedling establishment initiates already during seed desiccation and continues by additional distinct metabolic switches during vernalization and early germination. PMID:16963520

  19. A seed coat bedding assay to genetically explore in vitro how the endosperm controls seed germination in Arabidopsis thaliana.

    PubMed

    Lee, Keun Pyo; Lopez-Molina, Luis

    2013-01-01

    The Arabidopsis endosperm consists of a single cell layer surrounding the mature embryo and playing an essential role to prevent the germination of dormant seeds or that of nondormant seeds irradiated by a far red (FR) light pulse. In order to further gain insight into the molecular genetic mechanisms underlying the germination repressive activity exerted by the endosperm, a "seed coat bedding" assay (SCBA) was devised. The SCBA is a dissection procedure physically separating seed coats and embryos from seeds, which allows monitoring the growth of embryos on an underlying layer of seed coats. Remarkably, the SCBA reconstitutes the germination repressive activities of the seed coat in the context of seed dormancy and FR-dependent control of seed germination. Since the SCBA allows the combinatorial use of dormant, nondormant and genetically modified seed coat and embryonic materials, the genetic pathways controlling germination and specifically operating in the endosperm and embryo can be dissected. Here we detail the procedure to assemble a SCBA. PMID:24300527

  20. Disappearance of stored polyadenylic acid and mRNA during early germination of radish ( Raphanus sativus L.) embryo axes

    Microsoft Academic Search

    M. Delseny; Lorette Aspart; Y. Guitton

    1977-01-01

    Polyadenylic acid [poly (A)] is detected, characterized and quantitated in dry radish embryo axis RNA using a 3H poly (U) probe. The amount of poly (A) gradually decreases after the onset of soaking, and, after a few hours, recovers to the initial level. This variation is shown to result from the addition of two opposed phenomena: the decay of stored

  1. [Effects of Pb2+ stress on seed germination & seedling growth of Rabdosia rubescens].

    PubMed

    Kong, Si-Xin; Su, He; Zhan, Yan-Ting; Li, Hai-Kui; Cui, Xu-Sheng; Guo, Yu-Hai

    2014-11-01

    The seeds of Rabdosia rubescens were as the materials to research the impacts of different lead (Pb2+) concentrations(0, 135, 270, 540, 1 080 mg x L(-1)) on seed germination and seedling growth. The results show that: Low concentration of lead had no obvious effect on early germination of the seed, the germination vigor and germination speed were lightly higher but not significantly differed at the level of Pb concentration 135 mg x L(-1) with control group; Mid-high concentration of Pb solution (270-1 080 mg x L(-1)) significantly inhibited the seed germination and seedling growth, which reduced the seed germination rate, germination vigor, germination index, embryo root length and shoot length, growth index with increasing of Pb concentrations. There was a inhibitory effect on embryo shoot length and root length at mid-high lead concentrations stress, and stronger inhibitory effect on root , which was more sensitive than shoot to Pb stress(P < 0.05). Pb bioaccumulation coefficient (BC) was 0.76-2.59, increased with concentration of Pb; Pb enrichment in seedling mainly caused the growth inhibition. The fitting model predictive analyses show, the critical concentration of Pb, which causes the germination rate and biomass fresh weight reducing 10%, is 195.18, 101.65 mg x L(-1). PMID:25775796

  2. Effectiveness of a spontaneous carvacrol nanoemulsion against Salmonella enterica Enteritidis and Escherichia coli O157:H7 on contaminated broccoli and radish seeds.

    PubMed

    Landry, Kyle S; Micheli, Sean; McClements, David Julian; McLandsborough, Lynne

    2015-10-01

    The incidence of foodborne illness associated with the consumption of fresh produce has continued to increase over the past decade. Sprouts, such as mung bean, alfalfa, radish, and broccoli, are minimally processed and have been sources for foodborne illness. Currently, a 20,000 ppm calcium hypochlorite soak is recommended for the treatment of sprouting seeds. In this study, the efficacy of an antimicrobial carvacrol nanoemulsion was tested against Salmonella enterica subspecies enterica serovar Enteritidis (ATCC BAA-1045) or EGFP expressing Escherichia coli O157:H7 (ATCC 42895) contaminated sprouting seeds. Antimicrobial treatments were performed by soaking inoculated seeds in nanoemulsions (4000 or 8000 ppm) for 30 or 60 min. Following treatment, surviving cells were determined by performing plate counts and/or Most Probable Number (MPN) enumeration. Treated seeds were sprouted and tested for the presence of pathogens. Treatment successfully inactivated low levels (2 and 3 log CFU/g) of S. Enteritidis and E. coli on radish seeds when soaked for 60 min at concentrations ?4000 (0.4%) ppm carvacrol. This treatment method was not affective on contaminated broccoli seeds. Total sprout yield was not influenced by any treatments. These results show that carvacrol nanoemulsions may be an alternative treatment method for contaminated radish seeds. PMID:26187822

  3. Effect of three anthocyaninless genes on germination in tomato (Lycopersicon esculentum Mill.) II. Seed germination under stress conditions

    Microsoft Academic Search

    Bistra Atanassova; Lydia Shtereva; Emil Molle

    1997-01-01

    Seeds from four pairs of tomato isogenic\\/near-isogenic lines (IL\\/NIL) differing for anthocyaninless of Hoffmann (ah), three\\u000a pairs of IL\\/NILs differing for anthocyaninwithout (aw) and six pairs of IL\\/NILs differing for baby lea syndrome (bls) were\\u000a evaluated for their germination ability under stress conditions: low and high temperature, salt and osmotic stress. Mutant\\u000a genes affecting anthocyanin biosynthesis enhanced tomato germination capacity

  4. Heterogeneity of Catalase in Maturing and Germinated Cotton Seeds 1

    PubMed Central

    Kunce, Christine M.; Trelease, Richard N.

    1986-01-01

    To investigate possible charge and size heterogeneity of catalase (EC 1.11.1.6) in cotton (Gossypium hirsutum L. cv Deltapine 62), extracts of cotyledons from different developmental ages were subjected to nondenaturing polyacrylamide gel electrophoresis and isoelectric focusing. Special precautions (e.g. fresh homogenates, reducing media) were necessary to prevent artefacts due to enzyme modification during extraction and storage. When the gels were stained for enzyme activity, two distinct electrophoretic forms of catalase were resolved in extracts of maturing and mature cotton seeds. In germinated seeds, three additional cathodic forms were detected revealing a total of five electrophoretic variants. In green cotyledons, the two anodic forms characteristic of ungerminated seeds were less active; whereas, the most cathodic form was predominant. All forms of catalase were found in isolated glyoxysomes. Corresponding electrophoretic patterns were found on Western blots probed with anticatalase serum; no immunoreactive, catalytically inactive forms were detected. Western blots of sodium dodecyl sulfate-polyacrylamide gels revealed only one immunoreactive (55 kilodaltons) polypeptide in cotton extracts of all developmental ages. Results from isoelectric focusing and Ferguson plots indicate that the electrophoretic variants of catalase are charge isomers with a molecular weight of approximately 230,000. Images Fig. 1 Fig. 2 Fig. 3 Fig. 6 Fig. 7 PMID:16664956

  5. Dormancy and germination responses of halophyte seeds to the application of ethylene.

    PubMed

    Khan, M Ajmal; Ansari, Raziuddin; Gul, Bilquees; Li, Weiqiang

    2009-09-01

    Ethylene is invariably produced during seed germination but its role in regulating seed dormancy and germination is poorly understood. Seeds of 22 halophytic species having different life forms - salt secreting dicots, salt secreting monocots, stem succulents and leaf succulents were germinated in Petri dishes kept in a growth chamber set at 20/30 degrees C (night/day) temperature and a 12 hr light period. Sodium chloride and ethephon were added to the medium from the beginning of the experiment. Seed germination was recorded every other day for twenty days. Application of ethylene did not have any significant effect on releasing seeds from innate dormancy. However, it appeared to have a role in alleviation of salinity effects which varied from negative in certain species to almost complete alleviation of high salinity effects in others. Our data indicates that ethylene appears to have little role in breaking innate seed dormancy however, in most halophyte seeds studied, application of ethylene alleviate the salinity effect to various degrees. Halophyte seeds which could germinate under saline conditions approaching twice the salinity of seawater may offer clues to understand management of seed germination under highly saline conditions. PMID:19748455

  6. ?-Amylase from Starchless Seeds of Trigonella Foenum-Graecum and Its Localization in Germinating Seeds

    PubMed Central

    Srivastava, Garima; Kayastha, Arvind M.

    2014-01-01

    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

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

    PubMed

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

    2014-04-25

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

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

    USGS Publications Warehouse

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

    2009-01-01

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

  9. Nitric oxide implication in the control of seed dormancy and germination

    PubMed Central

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

    2013-01-01

    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

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

    PubMed Central

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

    2013-01-01

    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

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

    PubMed

    Eggert, Kai; von Wirén, Nicolaus

    2013-09-01

    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

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

    PubMed

    Escobar Escobar, Diego Fernando; Torres, Alba Marina

    2013-06-01

    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

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

    USGS Publications Warehouse

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

    2005-01-01

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

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

    Microsoft Academic Search

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

    2005-01-01

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

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

    E-print Network

    Paris-Sud XI, Université de

    Germination and storage of recalcitrant seeds of some tropical forest tree species F. Corbineau D-et-Marie-Curie (Paris VI), Paris, France Introduction Seeds have been termed orthodox or recalcitrant by Roberts (1973) to describe their storage behavior. Orthodox seeds tolerate dehydration down to 5-10% (dry weight basis

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

    Microsoft Academic Search

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

    2004-01-01

    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%

  17. Short Communication Effects of salinity and ingestion by ducks on germination patterns of Juncus subulatus seeds

    Microsoft Academic Search

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

    Changes in the nature of the seed coat caused by gut passage are considered to be the proximate causes of changes in germination patterns. Modifications of seed coat permeability may be decisive in saline environments (e.g. Mediterranean wetlands), in which the response of the seed to osmotic stress, or its resistance to toxicity caused by some ions may be affected.

  18. Effects of salinity and ingestion by ducks on germination patterns of Juncus subulatus seeds

    Microsoft Academic Search

    J. L. Espinar; L. V. García; J. Figuerola; A. J. Green; L. Clemente

    2006-01-01

    Changes in the nature of the seed coat caused by gut passage are considered to be the proximate causes of changes in germination patterns. Modifications of seed coat permeability may be decisive in saline environments (e.g. Mediterranean wetlands), in which the response of the seed to osmotic stress, or its resistance to toxicity caused by some ions may be affected.

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

    Microsoft Academic Search

    C. L. Leadem

    1987-01-01

    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

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

    E-print Network

    Yoon, Beyoung-Han

    1995-01-01

    and nonprimed seeds. Pansy seeds (Viola x wittrockiana 'Majestic Giant Blue Shade' and 'Crystal Bowl Sky Blue') were primed with several salts and PEG 15,000 at - 1.0 and - 2.0 MPa, for 3, 6, or 9 days at 23 C. Total percent germination (G) of nonprimed seeds...

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

    PubMed Central

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

    2014-01-01

    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

  2. [Effects of light intensity on seed germination and seedling early growth of Shorea wantianshuea].

    PubMed

    Yan, Xing-fu; Cao, Min

    2007-01-01

    With shading experiment, this paper studied the seed germination and seedling early growth of Shorea wantianshuea, a representative species in Xishuangbanna seasonal rain forest under different light intensity and forest habitat. The results showed that both 100% light and deepest shading did not facilitate the germination of S. wantianshuea seed, while medium shading accelerated the seed germination. Gap center was more appropriate to the seed germination than gap edge and under-canopy. The seeds in gap center had the highest germination rate and rapid germination. Under partially shading, the seedling height, diameter of basal stem, and leaf area per seedling were in their peak, while the root-shoot ratio decreased with increasing shading and achieved its maximum under 100% light. The specific leaf area increased with increasing shading in a certain range, and peaked under 4.2% light. Gap center was beneficial to the early seedling growth, with all growth parameters except root-shoot ratio peaked there. The effects of environmental factors, mainly light intensity and quality, on the seed germination and seedling growth of S. wantianshuea were discussed. PMID:17396494

  3. Annual dormancy cycles in buried seeds of shrub species: germination ecology of Sideritis serrata (Labiatae).

    PubMed

    Copete, M A; Herranz, J M; Ferrandis, P; Copete, E

    2015-07-01

    The germination ecology of Sideritis serrata was investigated in order to improve ex-situ propagation techniques and management of their habitat. Specifically, we analysed: (i) influence of temperature, light conditions and seed age on germination patterns; (ii) phenology of germination; (iii) germinative response of buried seeds to seasonal temperature changes; (iv) temperature requirements for induction and breaking of secondary dormancy; (v) ability to form persistent soil seed banks; and (vi) seed bank dynamics. Freshly matured seeds showed conditional physiological dormancy, germinating at low and cool temperatures but not at high ones (28/14 and 32/18 °C). Germination ability increased with time of dry storage, suggesting the existence of non-deep physiological dormancy. Under unheated shade-house conditions, germination was concentrated in the first autumn. S. serrata seeds buried and exposed to natural seasonal temperature variations in the shade-house, exhibited an annual conditional dormancy/non-dormancy cycle, coming out of conditional dormancy in summer and re-entering it in winter. Non-dormant seeds were clearly induced into dormancy when stratified at 5 or 15/4 °C for 8 weeks. Dormant seeds, stratified at 28/14 or 32/18 °C for 16 weeks, became non-dormant if they were subsequently incubated over a temperature range from 15/4 to 32/18 °C. S. serrata is able to form small persistent soil seed banks. The maximum seed life span in the soil was 4 years, decreasing with burial depth. This is the second report of an annual conditional dormancy/non-dormancy cycle in seeds of shrub species. PMID:25598169

  4. Re-induction of desiccation tolerance after germination of Cedrela fissilis Vell. seeds.

    PubMed

    Masetto, Tathiana E; Faria, Jose M; Fraiz, Ana C R

    2014-09-01

    This work aimed to characterize the re-induction of desiccation tolerance (DT) in germinated seeds, using polyethylene glycol (PEG 8000). Cell changes were investigated through cytological assays (cell viability and transmission electronic microscopy) as well as DNA integrity during loss and re-establishment of DT. The loss of DT was characterized by drying germinated seeds with different radicle lengths (1, 2, 3, 4 and 5 mm) in silica gel, decreasing the moisture content to ten percentage points intervals, followed by pre-humidification (100% RH / 24 h) and rehydration. To re-induce DT, germinated seeds were treated for 72 h with PEG (-2.04 MPa) and PEG (-2.04 MPa) + ABA (100 µM) before dehydration. Germinated seeds did not tolerate desiccation to 10% moisture content, irrespectively of the radicle length. However, when incubated in PEG, those with 1 and 2 mm long radicle attained 71% and 29% survival, respectively. The PEG+ABA treatment was efficient to re-establish DT in seeds with 1 mm long radicles (100% survival). The ultrastructural assays of the cells of germinated seeds with 2 and 5 mm length confirmed the obtained physiological results. Germinated seeds of C. fissilis constitute a useful tool for desiccation tolerance investigations. PMID:25140505

  5. Effects of waterlogging on seed germination of three Mediterranean oak species: Ecological implications

    NASA Astrophysics Data System (ADS)

    Pérez-Ramos, Ignacio M.; Marañón, Teodoro

    2009-05-01

    Soil water saturation during prolonged periods of time generates a negative impact on nearly all terrestrial plants. In Mediterranean woodlands, precipitation can be very abundant during the wet season, inducing temporary soil waterlogging, coinciding with the seed dispersal and germination time of many species. We investigated the effects of waterlogging on seed germination and early root growth of three coexisting oak species ( Quercus canariensis, Q. suber and Q. pyrenaica), by completely flooding of seeds for various periods of time. The three oak species showed a certain level of tolerance to waterlogging, only being affected those seeds subjected for long periods of submersion (over 30 days). Waterlogging during prolonged periods of time decreased the probability of seed germination in the three oak species, lengthened the time to germination, and hampered root development in two of the studied species. The main differences between oak species occurred in terms of root growth ( Q. canariensis being the less affected, and Q. suber the most); these differential responses could be related to a species rank of waterlogging tolerance. Thus inter-specific differences in germination responses to waterlogging could contribute to explain, at least partially, species habitat and distribution patterns across landscapes. Seed mass also played an important role on different aspects of germination, though its relative importance varied as function of species and waterlogging treatment. The tolerance to stress induced by waterlogging increased with seed mass, but only in the case of Q. canariensis.

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

    USGS Publications Warehouse

    Klinger, R.; Rejmanek, M.

    2010-01-01

    Seed predation and seed dispersal can have strong effects on early life history stages of plants. These processes have often been studied as individual effects, but the degree to which their relative importance co-varies with seed predator abundance and how this influences seed germination rates is poorly understood. Therefore, we used a combination of observations and field experiments to determine the degree to which germination rates of the palm Astrocaryum mexicanum varied with abundance of a small mammal seed predator/disperser, Heteromysdesmarestianus, in a lowland tropical forest. Patterns of abundance of the two species were strongly related; density of H. desmarestianus was low in sites with low density of A. mexicanum and vice versa. Rates of predation and dispersal of A. mexicanum seeds depended on abundance of H. desmarestianus; sites with high densities of H. desmarestianus had the highest rates of seed predation and lowest rates of seed germination, but a greater total number of seeds were dispersed and there was greater density of seedlings, saplings, and adults of A. mexicanum in these sites. When abundance of H. desmarestianus was experimentally reduced, rates of seed predation decreased, but so did dispersal of A. mexicanum seeds. Critically, rates of germination of dispersed seeds were 5 times greater than undispersed seeds. The results suggest that the relationship between A. mexicanum and H. desmarestianus is a conditional mutualism that results in a strong local effect on the abundance of each species. However, the magnitude and direction of these effects are determined by the relative strength of opposing, but related, mechanisms. A. mexicanum nuts provide H. desmarestianus with a critical food resource, and while seed predation on A. mexicanum nuts by H. desmarestianus is very intense, A. mexicanum ultimately benefits because of the relatively high germination rates of its seeds that are dispersed by H. desmarestianus. ?? The Author(s) 2010.

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

    Microsoft Academic Search

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

    1998-01-01

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

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

    Microsoft Academic Search

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

    1991-01-01

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

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

    PubMed

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

    2013-01-30

    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

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

    PubMed Central

    2014-01-01

    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

  11. Regulation of soybean seed germination through ethylene production in response to reactive oxygen species

    PubMed Central

    Ishibashi, Yushi; Koda, Yuka; Zheng, Shao-Hui; Yuasa, Takashi; Iwaya-Inoue, Mari

    2013-01-01

    Background and Aims Despite their toxicity, reactive oxygen species (ROS) play important roles in plant cell signalling pathways, such as mediating responses to stress or infection and in programmed cell death, at lower levels. Although studies have indicated that hydrogen peroxide (H2O2) promotes seed germination of several plants such as Arabidopsis, barley, wheat, rice and sunflower, the role of H2O2 in soybean seed germination is not well known. The aim of this study therefore was to investigate the relationships between ROS, plant hormones and soybean seed germination. Methods An examination was made of soybean seed germination, the expression of genes related to ethylene biosynthesis, endogenous ethylene contents, and the number and area of cells in the root tip, using N-acetylcysteine, an antioxidant, to counteract the effect of ROS. Key Results H2O2 promoted germination, which N-acetylcysteine suppressed, suggesting that ROS are involved in the regulation of soybean germination. H2O2 was produced in the embryonic axis after imbibition. N-Acetylcysteine suppressed the expression of genes related to ethylene biosynthesis and the production of endogenous ethylene. Interestingly, ethephon, which is converted to ethylene, and H2O2 reversed the suppression of seed germination by N-acetylcysteine. Furthermore, morphological analysis revealed that N-acetylcysteine suppressed cell elongation at the root tip, and this suppression was also reversed by ethephon or H2O2 treatments, as was the case in germination. Conclusions In soybean seeds, ROS produced in the embryonic axis after imbibition induce the production of endogenous ethylene, which promotes cell elongation in the root tip. This appears to be how ROS regulate soybean seed germination. PMID:23131300

  12. Environmental signals for seed germination reflect habitat adaptations in four temperate Caryophyllaceae

    Microsoft Academic Search

    F. Vandelook; D. Van de Moer; J. A. Van Assche

    2008-01-01

    Summary 1. Requirements for dormancy break and seed germination are specific for all species and depend chiefly on phylogeny, geographical distribution, habitat preference and life cycle. Studying germina- tion requirements of closely related species with a similar geographic distribution allows one to attribute variation in germination requirements to differences in habitat preference between the species. 2. We investigated requirements for

  13. Terpenoid precursors of strigol as seed germination stimulants of broomrape ( Orobanche ramosa ) and witchweed ( Striga asiatica )

    Microsoft Academic Search

    Sidney L. Vail; Oliver D. Dailey; Eugene J. Blanchard; Armand B. Pepperman; James L. Riopel

    1990-01-01

    Strigol and some of its synthetic precursors and analogs are known to be germination stimulants for broomrape (Orobanche ramosa) and witchweed (Striga asiatica). Fifteen synthetic terpenoids, similar in structure to one of the four rings of the strigol molecule, were evaluated in\\u000a two bioassays as seed germination stimulants with broomrape, and nine were found to be active. Five of the

  14. Raffinose and Stachyose Metabolism are not Required for Efficient Soybean Seed Germination

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Raffinose family oligosaccharides (RFOs), which include raffinose and stachyose, are thought to be an important source of energy during seed germination. In contrast to their potential for promoting germination, RFOs represent anti-nutritional units for monogastric animals when consumed as a compone...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

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

    PubMed Central

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

    2015-01-01

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

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

    PubMed

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

    2004-09-01

    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

  18. UDP-glucuronic acid:soyasapogenol glucuronosyltransferase involved in saponin biosynthesis in germinating soybean seeds

    Microsoft Academic Search

    Yasunori Kurosawa; Hidenari Takahara; Masakazu Shiraiwa

    2002-01-01

    We detected UDP-glucuronic acid:soyasapogenol glucuronosyltransferase (UGASGT) activity in the microsomal fraction from germinating soybean (Glycine max [L.] Merr.) seed. A microsomal fraction was isolated from germinating soybean seed and treated with various detergents to solubilize the enzyme. UGASGT activity was monitored throughout purification using UDP-[U-14C]glucuronic acid and soyasapogenol B as substrates. Purification of UGASGT was achieved by HiTrap Q, Superdex

  19. EFFECT OF DISINFECTANTS IN IMPROVING SEED GERMINATION OF SUAEDA FRUTICOSA UNDER SALINE CONDITIONS

    Microsoft Academic Search

    ABDUL HAMEED; MUHAMMAD ZAHEER AHMED; SALMAN GULZAR; M. AJMAL KHAN

    2009-01-01

    This research examines the possible role of two commonly used disinfectants viz., hydrogen peroxide (H2O2) and sodium hypochlorite (NaOCl) in improving seed germination and rate of germination of a subtropical cash crop halophyte, Suaeda fruticosa under saline conditions. Brief seed pretreatment with H2O2 (0.34%) and NaOCl (2%) had the following effects in various salinity (0, 100, 200, 300 and 400

  20. Vermicompost treatment differentially affects seed germination, seedling growth and physiological status of vegetable crop species

    Microsoft Academic Search

    Gederts Ievinsh

    Vermicompost preparations are increasingly used in agricultural practice. There is a possibility, that crop plants are sensitive\\u000a to negative effect of vermicompost at early stages of development. The aim of the present study was to test the effects of\\u000a vermicompost on seed germination and seedling growth of different vegetable crop species. Vermicompost substitution inhibited\\u000a seed germination and seedling growth with

  1. Lipid components of borage ( Borago officinalis L.) seeds and their changes during germination

    Microsoft Academic Search

    S. P. J. Namal Senanayake; Fereidoon Shahidi

    2000-01-01

    The changes in composition of total and neutral lipids (NL) as well as glycolipids (GL) and phospholipids (PL) of borage (Borago officinalis L.) seeds, germinated in the dark at 25°C for 10 d, were studied. Total lipids constituted 34.0% of the dry matter of borage seeds. During germination, the content\\u000a of total lipids was decreased by 95%. NL accounted for

  2. Physiological and biochemical responses of rice seeds to phosphine exposure during germination.

    PubMed

    Niu, Xiaojun; Mi, Lina; Li, Yadong; Wei, Aishu; Yang, Zhiquan; Wu, Jiandong; Zhang, Di; Song, Xiaofei

    2013-11-01

    Rice seeds (Tianyou, 3618) were used to examine the physiological and biochemical responses to phosphine exposure during germination. A control (0 mg m(-3)) and four concentrations of phosphine (1.4 mg m(-3), 4.2 mg m(-3), 7.0 mg m(-3) and 13.9 mg m(-3)) were used to treat the rice seeds. Each treatment was applied for 90 min once per day for five days. The germination rate (GR); germination potential (GP); germination index (GI); antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); and lipid peroxidation measured through via malondialdehyde (MDA) were determined as indicators of the physiological and biochemical responses of the rice seeds to phosphine exposure. These indicators were determined once per day for five days. The results indicated that the GR, GP and GI of the rice seeds markedly decreased after phosphine exposure. The changes in the activities of the antioxidant enzymes due to the phosphine exposure were also significant. The exposure lowered the CAT and SOD activities and increased POD activity in the treated rice seeds compared with controls. The MDA content exhibited a slow increase trend with the increase of phosphine concentration. These results suggest that phosphine has inhibitory effects on seed germination. In addition, phosphine exposure caused oxidative stress in the seeds. The antioxidant enzymes could play a pivotal role against oxidative injury. Overall, the effect of phosphine on rice seeds is different from what has been reported previously for insects and mammals. PMID:23992639

  3. Role of a Heterotrimeric G Protein in Regulation of Arabidopsis Seed Germination1

    PubMed Central

    Ullah, Hemayet; Chen, Jin-Gui; Wang, Shucai; Jones, Alan M.

    2002-01-01

    Seed germination is regulated by many signals. We investigated the possible involvement of a heterotrimeric G protein complex in this signal regulation. Seeds that carry a protein null mutation in the gene encoding the alpha subunit of the G protein in Arabidopsis (GPA1) are 100-fold less responsive to gibberellic acid (GA), have increased sensitivity to high levels of Glc, and have a near-wild-type germination response to abscisic acid and ethylene, indicating that GPA1 does not directly couple these signals in germination control. Seeds ectopically expressing GPA1 are at least a million-fold more responsive to GA, yet still require GA for germination. We conclude that the GPA1 indirectly operates on the GA pathway to control germination by potentiation. We propose that this potentiation is directly mediated by brassinosteroids (BR) because the BR response and synthesis mutants, bri1-5 and det2-1, respectively, share the same GA sensitivity as gpa1 seeds. Furthermore, gpa1 seeds are completely insensitive to brassinolide rescue of germination when the level of GA in seeds is reduced. A lack of BR responsiveness is also apparent in gpa1 roots and hypocotyls suggesting that BR signal transduction is likely coupled by a heterotrimeric G protein at various points in plant development. PMID:12068128

  4. Integration of Auxin and Salt Signals by the NAC Transcription Factor NTM2 during Seed Germination in Arabidopsis1[W

    PubMed Central

    Park, Jungmin; Kim, Youn-Sung; Kim, Sang-Gyu; Jung, Jae-Hoon; Woo, Je-Chang; Park, Chung-Mo

    2011-01-01

    Seed germination is regulated through elaborately interacting signaling networks that integrate diverse environmental cues into hormonal signaling pathways. Roles of gibberellic acid and abscisic acid in germination have been studied extensively using Arabidopsis (Arabidopsis thaliana) mutants having alterations in seed germination. Auxin has also been implicated in seed germination. However, how auxin influences germination is largely unknown. Here, we demonstrate that auxin is linked via the IAA30 gene with a salt signaling cascade mediated by the NAM-ATAF1/2-CUC2 transcription factor NTM2/Arabidopsis NAC domain-containing protein 69 (for NAC with Transmembrane Motif1) during seed germination. Germination of the NTM2-deficient ntm2-1 mutant seeds exhibited enhanced resistance to high salinity. However, the salt resistance disappeared in the ntm2-1 mutant overexpressing the IAA30 gene, which was induced by salt in a NTM2-dependent manner. Auxin exhibited no discernible effects on germination under normal growth conditions. Under high salinity, however, whereas exogenous application of auxin further suppressed the germination of control seeds, the auxin effects were reduced in the ntm2-1 mutant. Consistent with the inhibitory effects of auxin on germination, germination of YUCCA 3-overexpressing plants containing elevated levels of active auxin was more severely influenced by salt. These observations indicate that auxin delays seed germination under high salinity through cross talk with the NTM2-mediated salt signaling in Arabidopsis. PMID:21450938

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

    Microsoft Academic Search

    T. L. Springer

    2005-01-01

    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,

  6. QTLs for seed vigor-related traits identified in maize seeds germinated under artificial aging conditions.

    PubMed

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

    2014-01-01

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

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

    PubMed

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

    2013-01-01

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

  8. Short communication Effect of sea salt and L-ascorbic acid on the seed germination of halophytes

    Microsoft Academic Search

    M. Ajmal Khan; M. Zaheer Ahmed; A. Hameed

    2006-01-01

    Effects of L-ascorbic acid and sea salt solutions on the seed germination of Atriplex stocksii, Arthrocnemum macrostachyum, Haloxylon stocksii, Suaeda fruticosa, Desmostachya bipinnata and Aeluropus lagopoides were studied. Increasing concentration of sea salt inhibited seed germination of all species with comparatively more adverse effect on A. stocksii and S. fruticosa than others. Pretreatment of seeds with L-ascorbic acid alleviated the

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

    Microsoft Academic Search

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

    2001-01-01

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

  10. Influence of temperature and salinity on germination of eelgrass ( Zostera marina L.) seeds

    NASA Astrophysics Data System (ADS)

    Pan, Jinhua; Jiang, Xin; Li, Xiaojie; Cong, Yizhou; Zhang, Zhuangzhi; Li, Zhiling; Zhou, Weili; Han, Houwei; Luo, Shiju; Yang, Guanpin

    2011-06-01

    Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass ( Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) ( P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 ( P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination rate at 14°C ( P<0.001). Although significant interaction was found between temperature and salinity ( P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China.

  11. Insights into the molecular mechanism of RGL2-mediated inhibition of seed germination in Arabidopsis thaliana

    PubMed Central

    2012-01-01

    Background Seed germination is of immense significance for agriculture and has been studied for centuries. Yet, our understanding of the molecular mechanisms underlying regulation of dormancy and germination is still in its infancy. Gibberellins are the key phytohormones that promote germination, and the DELLA protein RGL2 is the main signalling intermediate involved in this response. Germination is completely inhibited if functional RGL2 is overexpressed and/or stabilized; however, the molecular mechanisms of RGL2 function are still largely unknown. We therefore attempted to shed light onto some of the genetic events downstream of RGL2. Results Gene ontology of the transcriptome differentially regulated by RGL2, as well as extensive cross-comparison with other available microarray data indicates that RGL2-mediated inhibition of germination causes seeds to enter a state of dormancy. RGL2 also appears to differentially regulate a number of transcription factors, many of which are known to be involved in light- or phytohormone-mediated aspects of germination. A promoter analysis of differentially expressed genes identified an enrichment of several motifs that can be bound by specific transcription factors, for example GAMYB, ARF1, or Dof-type zinc fingers. We show that Dof-binding motifs indeed play a role in RGL2-mediated transcription. Using Chromatin Immunoprecipitation (ChIP), we show that RGL2 directly downregulates at least one cell wall modifying enzyme, which is predicted to constrain cell growth thereby leading to inhibition of seed germination. Conclusions Our results reveal that RGL2 controls various aspects of germination. Through the repression of cell wall modifying enzymes, cell growth is directly constrained to inhibit germination. Furthermore, RGL2 likely interacts with various types of proteins to regulate transcription, and differentially regulates several transcription factors. Collectively, our data indicate that gibberellins, acting via RGL2, control several aspects of seed germination. PMID:23035751

  12. Germination response of black and yellow seed coated canola ( Brassica napus ) lines to chemical treatments under cold temperature conditions

    Microsoft Academic Search

    Wentao Zhang; Lawrence V. Gusta

    2010-01-01

    Seed quality is a key critical component to produce well established and vigorous seedlings under cool soil (<10°C) conditions\\u000a experienced in Western Canada. A simple, relatively quick germination assay is required to separate small differences in seed\\u000a germination which can have a significant impact on seedling growth. It has long been established that phytohormones regulate\\u000a seed germination: abscisic acid inhibits

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

    PubMed Central

    Domínguez, Fernando; Cejudo, Francisco J.

    2014-01-01

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

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

    Microsoft Academic Search

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

    2009-01-01

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

  15. Thioredoxin-Linked Proteins Are Reduced during Germination of Medicago truncatula Seeds

    Microsoft Academic Search

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

    2007-01-01

    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 tran- sition in cereals. It is not known, however, whether Trx-linked redox changes are restricted to cereals or whether they

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

    Microsoft Academic Search

    E. A. Jeliazkova; L. E. Craker

    2003-01-01

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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  18. Effects of various treatments on seed germination and growth of carob (Ceratonia siliqua L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Carob (Ceratonia siliqua L.) plays an important role in Mediterranean landscape. It is commercially propagated by grafting which requires the generation of seedlings. However, its seeds are very recalcitrant and need pretreatment for germination. In this study, carob seeds harvested from both wild a...

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

    Microsoft Academic Search

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

    1994-01-01

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

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

    Microsoft Academic Search

    Ali Osman Sari; Mehmet Tutar

    2010-01-01

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

  1. Protein hydrophobic dressing on seeds aiming at the delay of undesirable germination

    Microsoft Academic Search

    Odilio Benedito Garrido Assis; Ariane Maria Leoni

    2009-01-01

    Polymer seed-coatings have been largely tested as an alternative method for preventing diseases and have the potential to be used to control undesirable germination and thereby increasing seed storage. Amongst these, the protein-based coatings can be applied with advantage of forming stable biodegradable and hydrophobic films. Due to their chemical structure, protein dressings act as efficient barriers for water uptake,

  2. The growth physics and water relations of red-light-induced germination in lettuce seeds

    Microsoft Academic Search

    Murray W. Nabors; Anton Lang

    1971-01-01

    Redlight is known to increase the growth potential in the embryo of photodormant lettuce seed, enabling it to overcome the resistance offered by the seed coats (particularly the endosperm) or by an osmotically active medium. Determinations of the water potential of lettuce embryos germinating in osmoticum. carried out with a modified gravimetric technique which eliminates errors intro, duced by solute

  3. glaziovii Ruhl. (Guttiferae) seed size and its relationship with the glaziovii germination speed and seedling size

    Microsoft Academic Search

    Luis L. Arteaga

    In the present work I analyzed the variability of the seeds size of Vismia glaziovii Ruhl. and its Vismia glaziovii Ruhl. and its Vismia glaziovii possible effect on germination speed and its seedling size. The results show that the size of the seeds does not vary signifi cantly between trees from which they came; but the variation as large as

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

    NASA Astrophysics Data System (ADS)

    Quilichini, Angélique; Debussche, Max

    2000-12-01

    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.

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

    Microsoft Academic Search

    Mitsuko Kagaya; Takashi Tani; Naoki Kachi

    2005-01-01

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

  6. Opposing Actions of Light in Seed Germination of Poa pratensis and Amaranthus arenicola.

    PubMed

    Hendricks, S B; Toole, V K; Borthwick, H A

    1968-12-01

    Action spectra were measured for suppression of germination of Poa pratensis L. and Amaranthus arenicola I. M. Johnston seed under prolonged or continuous irradiation. The action maxima for both types of seeds are near 720 nm. The maxima are unchanged in position or magnitude in the presence of radiation in the region of 600 to 670 nm adequate to maintain phytochrome predominantly in the far-red-absorbing form. A reversible potentiation of germination to change in form of phytochrome was observed for both seeds. The bearing of these findings on a high-energy regulatory light response is discussed. PMID:16657003

  7. Opposing Actions of Light in Seed Germination of Poa pratensis and Amaranthus arenicola

    PubMed Central

    Hendricks, S. B.; Toole, V. K.; Borthwick, H. A.

    1968-01-01

    Action spectra were measured for suppression of germination of Poa pratensis L. and Amaranthus arenicola I. M. Johnston seed under prolonged or continuous irradiation. The action maxima for both types of seeds are near 720 nm. The maxima are unchanged in position or magnitude in the presence of radiation in the region of 600 to 670 nm adequate to maintain phytochrome predominantly in the far-red-absorbing form. A reversible potentiation of germination to change in form of phytochrome was observed for both seeds. The bearing of these findings on a high-energy regulatory light response is discussed. PMID:16657003

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

    NASA Technical Reports Server (NTRS)

    Levine, H. G.; Piastuch, W. C.; Sager, J. C. (Principal Investigator)

    1999-01-01

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

  9. Laboratory germination of seeds from 10 British species of Potamogeton

    Microsoft Academic Search

    Fiona Hay; Robin Probert; Michelle Dawson

    2008-01-01

    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

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

    PubMed

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

    2012-07-13

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

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

    PubMed

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

    2014-01-01

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

  12. Modification of Seed Germination Performance through Cold Plasma Chemistry Technology

    Microsoft Academic Search

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

    2000-01-01

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

  13. Seed germination ecology of the threatened endemic Iberian Delphinium fissum subsp. sordidum (Ranunculaceae)

    Microsoft Academic Search

    José M. Herranz; Pablo Ferrandis; Esmeralda Martínez-Duro

    2010-01-01

    Seeds of Delphinium fissum subsp. sordidum are physiologically dormant at maturity, with underdeveloped embryos; thus they have morphophysiological dormancy (MPD).\\u000a The aims of this study were to determine the requirements for embryo growth, dormancy break and germination, to characterise\\u000a the type of seed dormancy and to evaluate the effects of light, seed age, pollination mechanism, and inter-annual and inter-population\\u000a variability

  14. Modeling analysis on germination and seedling growth using ultrasound seed pretreatment in switchgrass.

    PubMed

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

    2012-01-01

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

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

    PubMed Central

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

    2012-01-01

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

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

    PubMed Central

    Jiang, Wenbo; Yu, Diqiu

    2009-01-01

    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

  17. The effect of brassinosteroids on radish (Raphanus sativus L.) seedlings growing under cadmium stress

    Microsoft Academic Search

    S. Anuradha; S. S. R. Rao

    The effect of 24-epibrassinolide and 28-homobrassinolide on seed germination and seedling growth of radish ( Ra- phanus sativus L.) was studied under cadmium toxicity. The impact of brassinosteroids (BRs) on free proline levels and the activity of antioxidant enzymes catalase (CAT; EC 1.11.1.6), peroxidase (POD; EC 1.11.1.7), superoxide dis- mutase (SOD; EC 1.15.1.1), ascorbic peroxidase (APOX; EC 1.11.1.11) and guaiacol

  18. Morphology, physiology and environmental effects of triploid watermelon seed germination

    E-print Network

    Grange, Stacie Lee

    2001-01-01

    -part approach to the problem. First, the morphology of the seed coat was examined. In the morphology section, scanning electron microscopy (SEM) was used to determine the basic structural differences in the seed coat. Seed components characteristics were also...

  19. Morphology, physiology and environmental effects of triploid watermelon seed germination 

    E-print Network

    Grange, Stacie Lee

    2001-01-01

    -part approach to the problem. First, the morphology of the seed coat was examined. In the morphology section, scanning electron microscopy (SEM) was used to determine the basic structural differences in the seed coat. Seed components characteristics were also...

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

    NASA Astrophysics Data System (ADS)

    Gonzalez, S. L.; Ghermandi, L.

    2012-09-01

    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.

  1. Seed weight and germination behavior of the submerged plant Potamogeton pectinatus in the arid zone of northwest China

    PubMed Central

    Li, Zhongqiang; Lu, Wei; Yang, Lei; Kong, Xianghong; Deng, Xuwei

    2015-01-01

    Variation in seed weight is common within and among plant species, but few studies have attempted to document the pattern of seed weight and germination attributes for aquatic macrophytes at a large scale. This study examined within-species variation in seed weight and germination attributes and the effects of environmental factors on seed traits of the submerged plant Potamogeton pectinatus in the arid zone of northwest China. Our results showed that the average seed weight was 0.24 g per 100 seeds with a coefficient of variation (CV) of 28.4% among the eight P. pectinatus populations. The total germination fraction of seeds of P. pectinatus was relatively poor, less than 35% in seven P. pectinatus populations, and the lowest germination percentage found was only 2%. There were significant differences in seed weight, time to onset of germination, and total germination fraction among the eight different populations. Hierarchical partitioning analysis showed a strongly positive correlation between seed weight and water temperature and pH. Seed weight and the maternal environmental factors significantly affected both time to initiation of germination and total germination fraction. Our results suggest that (1) seed weight variation in P. pectinatus primarily is the result of temperature variation during fruit development; (2) relatively poor germination fraction suggests that seeds are relatively unimportant in the short-term survival of populations and that it may be another adaptive trait allowing plants to take place in the right place and at the right time, especially in harsh environment; and (3) variation in seed germination traits should be determined by local environmental and intrinsic factors that interact in a complex fashion. PMID:25897389

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

    PubMed Central

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

    2011-01-01

    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

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

    Microsoft Academic Search

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

    2003-01-01

    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

  4. Proline Metabolism and Cross-Tolerance to Salinity and Heat Stress in Germinating Wheat Seeds

    Microsoft Academic Search

    S. Q. Song; Y. B. Lei; X. R. Tian

    2005-01-01

    Germination\\/growth of wheat (Triticum aestivum L., cv. Zimai 1) seeds and changes in the levels of proline and protein as well as in activities of key enzymes involved\\u000a in proline metabolism in response to salinity-, heat-stresses and their cross-stress were studied. With decreasing water potential\\u000a caused by increasing concentrations of NaCl, germination percentage, fresh weight of seedlings and protein amount

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

    Microsoft Academic Search

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

    1996-01-01

    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

  6. Tomato seed germination: regulation of different response modes by phytochrome B2 and phytochrome A

    Microsoft Academic Search

    KLAUS-J. APPENROTH; GABRIELE LENK; LYDIA GOLDAU; RAMESHWAR SHARMA

    2006-01-01

    Lycopersicon esculentum seeds germinate after rehydra- tion in complete darkness. This response was inhibited by a far-red light (FR) pulse, and the inhibition was reversed by a red light (R) pulse. Comparison of germination in phytochrome-deficient mutants ( phyA , phyB1 , phyB2 , phyAB1 , phyB1B2 and phyAB1B2 ) showed that phytochrome B2 ( PhyB2 ) mediates both responses.

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

    NASA Astrophysics Data System (ADS)

    Vange, Vibekke; Heuch, Ivar; Vandvik, Vigdis

    2004-05-01

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

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

    PubMed

    Hendricks, S B; Taylorson, R B

    1974-09-01

    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

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

    PubMed Central

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

    1974-01-01

    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

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

    PubMed

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

    2015-02-01

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

  11. Effects of a warmer climate on seed germination in the subarctic

    PubMed Central

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

    2009-01-01

    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

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

    PubMed Central

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

    1989-01-01

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

  13. Rhizonin A from Burkholderia sp. KCTC11096 and its growth promoting role in lettuce seed germination.

    PubMed

    Kang, Sang-Mo; Khan, Abdul Latif; Hussain, Javid; Ali, Liaqat; Kamran, Muhammad; Waqas, Muhammad; Lee, In-Jung

    2012-01-01

    We isolated and identified a gibberellin-producing Burkholderia sp. KCTC 11096 from agricultural field soils. The culture filtrate of plant growth promoting rhizobacteria (PGPR) significantly increased the germination and growth of lettuce and Chinese cabbage seeds. The ethyl acetate extract of the PGPR culture showed significantly higher rate of lettuce seed germination and growth as compared to the distilled water treated control. The ethyl acetate fraction of the Burkholderia sp. was subjected to bioassay-guided isolation and we obtained for the first time from a Burkholderia sp. the plant growth promoting compound rhizonin A (1), which was characterized through NMR and MS techniques. Application of various concentrations of 1 significantly promoted the lettuce seed germination as compared to control. PMID:22759911

  14. Metabolites inhibiting germination of Orobanche ramosa seeds produced by Myrothecium verrucaria and Fusarium compactum.

    PubMed

    Andolfi, Anna; Boari, Angela; Evidente, Antonio; Vurro, Maurizio

    2005-03-01

    Myrothecium verrucaria and Fusarium compactum were isolated from diseased Orobanche ramosa plants collected in southern Italy to find potential biocontrol agents of this parasitic weed. Both fungi grown in liquid culture produced metabolites that inhibited the germination of O. ramosa seeds at 1-10 muM. Eight metabolites were isolated from M. verrucaria culture extracts. The main metabolite was identified as verrucarin E, a disubstituted pyrrole not belonging to the trichothecene group. Seven compounds were identified by spectroscopic methods as macrocyclic trichothecenes, namely, verrucarins A, B, M, and L acetate, roridin A, isotrichoverrin B, and trichoverrol B. The main metabolite produced by F. compactum was neosoloaniol monoacetate, a trichothecene. All the trichothecenes proved to be potent inhibitors of O. ramosa seed germination and possess strong zootoxic activity when assayed on Artemia salina brine shrimps. Verrucarin E is inactive on both seed germination and zootoxic assay. PMID:15740046

  15. Glucoraphanin and 4-hydroxyglucobrassicin contents in seeds of 59 cultivars of broccoli, raab, kohlrabi, radish, cauliflower, brussels sprouts, kale, and cabbage.

    PubMed

    West, Leslie G; Meyer, Keith A; Balch, Barbara A; Rossi, Frank J; Schultz, Michael R; Haas, George W

    2004-02-25

    The importance of dietary sulforaphane in helping maintain good health continues to gain support within the health-care community and awareness among U.S. consumers. In addition to the traditional avenue for obtaining sulforaphane, namely, the consumption of appropriate cruciferous vegetables, other consumer products containing added glucoraphanin, the natural precursor to sulforaphane, are now appearing in the United States. Crucifer seeds are a likely source for obtaining glucoraphanin, owing to a higher concentration of glucoraphanin and the relative ease of processing seeds as compared to vegetative parts. Seeds of several commonly consumed crucifers were analyzed not only for glucoraphanin but also for components that might have negative health implications, such as certain indole-containing glucosinolates and erucic acid-containing lipids. Glucoraphanin, 4-hydroxyglucobrassicin, other glucosinolates, and lipid erucic acid were quantified in seeds of 33 commercially available cultivars of broccoli, 4 cultivars each of kohlrabi, radish, cauliflower, Brussels sprouts, kale, and cabbage, and 2 cultivars of raab. PMID:14969551

  16. Presowing Hardening of the Host with Phenolic Acids Reduces Induction of Seed Germination in the Root Parasite Striga asiatica

    Microsoft Academic Search

    Bharathalakshmi; Jayachandra

    1980-01-01

    Striga asiatica (L.) Kuntze, a root parasite, causes severe loss of yield in sorghum and several other crops. The seeds of the parasite are induced to germinate by a stimulant in the host root exudate. Presowing hardening of the host with vanillic acid, caffeic acid and ferulic acid (25 ppm) reduces the induction of seed germination in the parasite by

  17. Arabidopsis ABA INSENSITIVE4 Regulates Lipid Mobilization in the Embryo and Reveals Repression of Seed Germination by the Endosperm

    Microsoft Academic Search

    Steven Penfield; Yi Li; Alison D. Gilday; Stuart Graham; Ian A. Graham

    2006-01-01

    Regulation of seed germination requires coordinate action by the embryo and surrounding endosperm. We used Arabidopsis thaliana to establish the relative roles of embryo and endosperm in the control of seed germination and seedling establishment. We previously showed that endospermic oil reserves are used postgerminatively via gluconeo- genesis to fuel seedling establishment and that lipid breakdown is repressed by abscisic

  18. EFFECT OF COMPATIBLE OSMOTICA AND PLANT GROWTH REGULATORS IN ALLEVIATING SALINITY STRESS ON THE SEED GERMINATION OF ALLENROLFEA OCCIDENTALIS

    Microsoft Academic Search

    BILQUEES GUL; M. AJMAL KHAN

    2008-01-01

    Allenrolfea occidentalis, a perennial halophytic shrub in the family Chenopodiaceae is widely distributed in the inland salt marshes and salt playas of western United States. Experiments were conducted to determine the influence of compatible osmotica (betaine and proline) and growth regulators (gibberellic acid and kinetin) in alleviating salinity stress on the seed germination of A. occidentalis. Seed germination decreased with

  19. DELAY OF GERMINATION 1 mediates a conserved coat-dormancy mechanism for the temperature- and gibberellin-dependent control of seed germination.

    PubMed

    Graeber, Kai; Linkies, Ada; Steinbrecher, Tina; Mummenhoff, Klaus; Tarkowská, Danuše; Ture?ková, Veronika; Ignatz, Michael; Sperber, Katja; Voegele, Antje; de Jong, Hans; Urbanová, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard

    2014-08-26

    Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the delay of germination 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapping experiments between Brassicaceae species we show that the DOG1-mediated dormancy mechanism is conserved. Biomechanical analyses show that this mechanism regulates the material properties of the endosperm, a seed tissue layer acting as germination barrier to control coat dormancy. We found that DOG1 inhibits the expression of gibberellin (GA)-regulated genes encoding cell-wall remodeling proteins in a temperature-dependent manner. Furthermore we demonstrate that DOG1 causes temperature-dependent alterations in the seed GA metabolism. These alterations in hormone metabolism are brought about by the temperature-dependent differential expression of genes encoding key enzymes of the GA biosynthetic pathway. These effects of DOG1 lead to a temperature-dependent control of endosperm weakening and determine the optimal temperature for germination. The conserved DOG1-mediated coat-dormancy mechanism provides a highly adaptable temperature-sensing mechanism to control the timing of germination. PMID:25114251

  20. DELAY OF GERMINATION 1 mediates a conserved coat-dormancy mechanism for the temperature- and gibberellin-dependent control of seed germination

    PubMed Central

    Graeber, Kai; Linkies, Ada; Steinbrecher, Tina; Mummenhoff, Klaus; Tarkowská, Danuše; Ture?ková, Veronika; Ignatz, Michael; Sperber, Katja; Voegele, Antje; de Jong, Hans; Urbanová, Terezie; Strnad, Miroslav; Leubner-Metzger, Gerhard

    2014-01-01

    Seed germination is an important life-cycle transition because it determines subsequent plant survival and reproductive success. To detect optimal spatiotemporal conditions for germination, seeds act as sophisticated environmental sensors integrating information such as ambient temperature. Here we show that the DELAY OF GERMINATION 1 (DOG1) gene, known for providing dormancy adaptation to distinct environments, determines the optimal temperature for seed germination. By reciprocal gene-swapping experiments between Brassicaceae species we show that the DOG1-mediated dormancy mechanism is conserved. Biomechanical analyses show that this mechanism regulates the material properties of the endosperm, a seed tissue layer acting as germination barrier to control coat dormancy. We found that DOG1 inhibits the expression of gibberellin (GA)-regulated genes encoding cell-wall remodeling proteins in a temperature-dependent manner. Furthermore we demonstrate that DOG1 causes temperature-dependent alterations in the seed GA metabolism. These alterations in hormone metabolism are brought about by the temperature-dependent differential expression of genes encoding key enzymes of the GA biosynthetic pathway. These effects of DOG1 lead to a temperature-dependent control of endosperm weakening and determine the optimal temperature for germination. The conserved DOG1-mediated coat-dormancy mechanism provides a highly adaptable temperature-sensing mechanism to control the timing of germination. PMID:25114251

  1. The ecophysiology of seed persistence: a mechanistic view of the journey to germination or demise.

    PubMed

    Long, Rowena L; Gorecki, Marta J; Renton, Michael; Scott, John K; Colville, Louise; Goggin, Danica E; Commander, Lucy E; Westcott, David A; Cherry, Hillary; Finch-Savage, William E

    2015-02-01

    Seed persistence is the survival of seeds in the environment once they have reached maturity. Seed persistence allows a species, population or genotype to survive long after the death of parent plants, thus distributing genetic diversity through time. The ability to predict seed persistence accurately is critical to inform long-term weed management and flora rehabilitation programs, as well as to allow a greater understanding of plant community dynamics. Indeed, each of the 420000 seed-bearing plant species has a unique set of seed characteristics that determine its propensity to develop a persistent soil seed bank. The duration of seed persistence varies among species and populations, and depends on the physical and physiological characteristics of seeds and how they are affected by the biotic and abiotic environment. An integrated understanding of the ecophysiological mechanisms of seed persistence is essential if we are to improve our ability to predict how long seeds can survive in soils, both now and under future climatic conditions. In this review we present an holistic overview of the seed, species, climate, soil, and other site factors that contribute mechanistically to seed persistence, incorporating physiological, biochemical and ecological perspectives. We focus on current knowledge of the seed and species traits that influence seed longevity under ex situ controlled storage conditions, and explore how this inherent longevity is moderated by changeable biotic and abiotic conditions in situ, both before and after seeds are dispersed. We argue that the persistence of a given seed population in any environment depends on its resistance to exiting the seed bank via germination or death, and on its exposure to environmental conditions that are conducive to those fates. By synthesising knowledge of how the environment affects seeds to determine when and how they leave the soil seed bank into a resistance-exposure model, we provide a new framework for developing experimental and modelling approaches to predict how long seeds will persist in a range of environments. PMID:24618017

  2. Tolerance and recovery responses of playa halophytes to light, salinity and temperature stresses during seed germination

    Microsoft Academic Search

    M. Zaheer Ahmed; M. Ajmal Khan

    2010-01-01

    Halogeton glomeratus (M. Bieb.) C.A. Mey., Lepidium latifolium Linn. and Peganum harmala Linn. are distributed in temperate salt playa habitats of Upper Hunza, Pakistan. Seeds were germinated under various salinity (0–500mM NaCl), light (12h-light:12h-dark and 24h-dark) and temperature (5\\/15, 10\\/20, 15\\/25, 20\\/30, and 25\\/35°C, dark\\/light) regimes for 20 days to determine the optimal conditions for germination and recovery of seeds

  3. Seed germination and seedling growth of Suaeda salsa under salt stress

    Microsoft Academic Search

    De-Yu Duan; Wei-Qiang Li; Xiao-Jing Liu; Hua Ouyang; Ping An

    The effect of increasing concentrations (0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.6 mol l-1) of dif- ferent salts (Na2SO4, Na2CO3, MgSO4, NaCl, MgCl2) in solution and soil extract solu- tions of comparable osmotic potentials on germination of Suaeda salsa seeds was studied. Seed germination decreased significantly with increased salinity. Germina - tion inhibition was in the following order: MgCl2 >

  4. Effects of phthalate ester treatment on seed germination and antioxidant enzyme activities of Phaseolus radiatus L.

    PubMed

    Liu, Wenli; Zhang, Chongbang; Liu, Shuyuan

    2014-05-01

    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

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

    E-print Network

    Whatley, Christopher Marc

    1988-01-01

    in the fruit portions of the plant. Caffeine is known to be a germination inhibitor in some plants (Andus 1963). Lipid reserves present in the endosperm of the seed can also inhibit germination. Ives (1923) concluded that lipid reserves in yaupon seeds... 1984). In Texas alone, more than 800, 000 hectares of land could eventually be surface mined (Brown and Deuel 1980). Plant reclamation activities can be categorized as native versus non-native and woody versus non-woody species. The ideal mixture...

  6. Effect of flooding and draw-down disturbance on germination from a seashore meadow seed bank

    USGS Publications Warehouse

    Jutila, H.M.

    2001-01-01

    The objective of this study was to investigate the effects of flooding and draw-down on the germination from the coastal grassland seed banks and to determine whether the effect of flooding varies between the delta and the seashore. Seed bank samples were collected from three shore transects in SW Finland, two on the shore of the Baltic Sea and one on the delta of River Kokema??enjoki. Samples were germinated in non-flooded and flooded conditions for over a month, after which both treatments were maintained in non-flooded conditions. A total of 9267 seedlings of 47 species germinated and mean density of seeds in the soil was ca. 84 000/m2. Most of the seedlings were monocots (98%) and perennials (98%). Ca. 30-40% of the species found in the above-ground vegetation had a seed bank including the majority of the most abundant species. The number of seeds and species richness increased as the organic layer became thicker. The organic layer was thicker in the seashore samples and the seed bank was significantly larger than in the delta. The flooding and draw-down treatment significantly increased the number of germinating seedlings in the seashore and also increased species richness in two transects, one in the delta and the other in the seashore. Two species, Schoenoplectus tabernaemontani and Typha latifolia, had significantly higher germination in the flooded treatment than in the non-flooded. Apparently, many species in these coastal grasslands have adapted to flood disturbance and for seeds of some species flooding may work as a positive signal, possibly breaking dormancy.

  7. [Testing of germination rate of hybrid rice seeds based on near-infrared reflectance spectroscopy].

    PubMed

    Li, Yi-nian; Jiang, Dan; Liu, Ying-ying; Ding, Wei-min; Ding, Qi-shuo; Zha, Liang-yu

    2014-06-01

    Germination rate of rice seeds was measured according to technical stipulation of germination testing for agricultural crop seeds at present. There existed many faults for this technical stipulation such as long experimental period, more costing and higher professional requirement. A rapid and non-invasive method was put forward to measure the germination rate of hybrid rice seeds based on near-infrared reflectance spectroscopy. Two varieties of hybrid rice seeds were aged artificially at temperature 45 degrees C and humidity 100% condition for 0, 24, 48, 72, 96, 120 and 144 h. Spectral data of 280 samples for 2 varieties of hybrid rice seeds with different aging time were acquired individually by near-infrared spectra analyzer. Spectral data of 280 samples for 2 varieties of hybrid rice seeds were randomly divided into calibration set (168 samples) and prediction set (112 samples). Gormination rate of rice seed with different aging time was tested. Regression model was established by using partial least squares (PLS). The effect of the different spectral bands on the accuracy of models was analyzed and the effect of the different spectral preprocessing methods on the accuracy of models was also compared. Optimal model was achieved under the whole bands and by using standardization and orthogonal signal correction (OSC) preprocessing algorithms with CM2000 software for spectral data of 2 varieties of hybrid rice seeds, the coefficient of determination of the calibration set (Rc) and that of the prediction set (Rp) were 0.965 and 0.931 individually, standard error of calibration set (SEC) and that of prediction set (SEP) were 1.929 and 2.899 respectively. Relative error between tested value and predicted value for prediction set of rice seeds is below 4.2%. The experimental results show that it is feasible that rice germination rate is detected rapidly and nondestructively by using the near-infrared spectroscopy analysis technology. PMID:25358159

  8. Vacuolar H+-ATPase Is Expressed in Response to Gibberellin during Tomato Seed Germination1

    PubMed Central

    Cooley, Michael B.; Yang, Hong; Dahal, Peetambar; Mella, R. Alejandra; Downie, A. Bruce; Haigh, Anthony M.; Bradford, Kent J.

    1999-01-01

    Completion of germination (radicle emergence) by gibberellin (GA)-deficient (gib-1) mutant tomato (Lycopersicon esculentum Mill.) seeds is dependent upon exogenous GA, because weakening of the endosperm tissue enclosing the radicle tip requires GA. To investigate genes that may be involved in endosperm weakening or embryo growth, differential cDNA display was used to identify mRNAs differentially expressed in gib-1 seeds imbibed in the presence or absence of GA4+7. Among these was a GA-responsive mRNA encoding the 16-kD hydrophobic subunit c of the V0 membrane sector of vacuolar H+-translocating ATPases (V-ATPase), which we termed LVA-P1. LVA-P1 mRNA expression in gib-1 seeds was dependent on GA and was particularly abundant in the micropylar region prior to radicle emergence. Both GA dependence and tissue localization of LVA-P1 mRNA expression were confirmed directly in individual gib-1 seeds using tissue printing. LVA-P1 mRNA was also expressed in wild-type seeds during development and germination, independent of exogenous GA. Specific antisera detected protein subunits A and B of the cytoplasmic V1 sector of the V-ATPase holoenzyme complex in gib-1 seeds only in the presence of GA, and expression was localized to the micropylar region. The results suggest that V-ATPase plays a role in GA-regulated germination of tomato seeds. PMID:10594121

  9. Variation in Germination and Amino Acid Leakage of Seeds with Temperature Related to Membrane Phase Change

    PubMed Central

    Hendricks, Sterling B.; Taylorson, Ray B.

    1976-01-01

    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

  10. COMUNICAÇÃO EFEITO DA TEMPERATURA E DO TEGUMENTO NA GERMINAÇÃO DE SEMENTES DE Calophyllum brasiliense 1 Effect of temperature and coat in the germination of Calophyllum brasiliense seeds1

    Microsoft Academic Search

    Fernanda Carlota Nery; Amauri Alves de Alvarenga; Cristina Filomena Justo; Sara Dousseau; Carlos Vinício Vieira

    Due to the increasing demand for informations about species with potential for being introduced in degraded environment, it is important the physiological knowledge of seeds germination, aiming their rational exploration. The objective of this research was to evaluate the behaviour of seed imbibition, to determine the germination optimum temperature and the effect of coat seeds withdrawing in the germination of

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

    NASA Astrophysics Data System (ADS)

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

    2001-02-01

    Seeds of Drosera anglica collected in Sweden were dormant at maturity in late summer, and dormancy break occurred during cold stratification. Stratified seeds required light for germination, but light had to be given after temperatures were high enough to be favorable for germination. Seeds stratified in darkness at 5/1 °C and incubated in light at 12/12 h daily temperature regimes of 15/6, 20/10 and 25/15 °C germinated slower and to a significantly lower percentage at each temperature regime than those stratified in light and incubated in light. Length of the stratification period required before seeds would germinate to high percentages depended on (1) whether seeds were in light or in darkness during stratification and during the subsequent incubation period, and (2) the temperature regime during incubation. Seeds collected in 1999 germinated to 4, 24 and 92 % in light at 15/6, 20/10 and 25/15 °C, respectively, after 2 weeks of stratification in light. Seeds stratified in light for 18 weeks and incubated in light at 15/6, 20/10 and 25/15 °C germinated to 87, 95 and 100 %, respectively, while those stratified in darkness for 18 weeks and incubated in light germinated to 6, 82 and 91 %, respectively. Seeds collected from the same site in 1998 and 1999, stratified in light at 5/1 °C and incubated in light at 15/6 °C germinated to 22 and 87 %, respectively, indicating year-to-year variation in degree of dormancy. As dormancy break occurred, the minimum temperature for germination decreased. Thus, seed dormancy is broken in nature by cold stratification during winter, and by spring, seeds are capable of germinating at low habitat temperatures, if they are exposed to light.

  12. Dynamic Proteomics Emphasizes the Importance of Selective mRNA Translation and Protein Turnover during Arabidopsis Seed Germination*

    PubMed Central

    Galland, Marc; Huguet, Romain; Arc, Erwann; Cueff, Gwendal; Job, Dominique; Rajjou, Loïc

    2014-01-01

    During seed germination, the transition from a quiescent metabolic state in a dry mature seed to a proliferative metabolic state in a vigorous seedling is crucial for plant propagation as well as for optimizing crop yield. This work provides a detailed description of the dynamics of protein synthesis during the time course of germination, demonstrating that mRNA translation is both sequential and selective during this process. The complete inhibition of the germination process in the presence of the translation inhibitor cycloheximide established that mRNA translation is critical for Arabidopsis seed germination. However, the dynamics of protein turnover and the selectivity of protein synthesis (mRNA translation) during Arabidopsis seed germination have not been addressed yet. Based on our detailed knowledge of the Arabidopsis seed proteome, we have deepened our understanding of seed mRNA translation during germination by combining two-dimensional gel-based proteomics with dynamic radiolabeled proteomics using a radiolabeled amino acid precursor, namely [35S]-methionine, in order to highlight de novo protein synthesis, stability, and turnover. Our data confirm that during early imbibition, the Arabidopsis translatome keeps reflecting an embryonic maturation program until a certain developmental checkpoint. Furthermore, by dividing the seed germination time lapse into discrete time windows, we highlight precise and specific patterns of protein synthesis. These data refine and deepen our knowledge of the three classical phases of seed germination based on seed water uptake during imbibition and reveal that selective mRNA translation is a key feature of seed germination. Beyond the quantitative control of translational activity, both the selectivity of mRNA translation and protein turnover appear as specific regulatory systems, critical for timing the molecular events leading to successful germination and seedling establishment. PMID:24198433

  13. Factors Affecting Attachment of Enterobacter cloacae to Germinating Cotton Seed

    Microsoft Academic Search

    M. A. Hood; K. V. van Dijk; E. B. Nelson

    1998-01-01

    Attachment of Enterobacter cloacae EcCT-50,—a biological seed protectant used to control the seed-rotting fungi, Pythium ultimum—to cotton seed was examined using conventional fluorescent microscopy (CFM), scanning electron microscopy (SEM), and laser\\u000a scanning microscopy (LSM). In sand microcosms, E. cloacae quickly attached to the seed coat, with maximum attachment, 3 to 5 h after inoculation at 24°C. In contrast, initial attachment

  14. Effects of ingestion of seeds by sika deer ( Cervus nippon ) and dung presence on their germination in a herbaceous community

    Microsoft Academic Search

    Haruna Ishikawa

    2010-01-01

    In a herbaceous community subjected to continual impacts of sika deer (Cervus\\u000a nippon), I examined the effects of seed ingestion by deer on seeds by comparing the ripening and germination rates of seeds of two\\u000a dominant species, Zoysia japonica and Hydrocotyle maritima, between seeds taken out of fecal pellets (deer-ingested seeds) and mature seeds collected directly from living plants (control

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

    PubMed Central

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

    2011-01-01

    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

  16. 7 CFR 201.53 - Source of seeds for germination.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...the test shall be obtained by separating the sample into two components as follows: (1) Pure seed and (2) other crop seed, weed seed, and inert matter. In making this separation at least 1/4 of the quantity required for a regular purity...

  17. Cold Radiofrequency Plasma Treatment Modifies Wettability and Germination Speed of Plant Seeds

    NASA Astrophysics Data System (ADS)

    Bormashenko, Edward; Grynyov, Roman; Bormashenko, Yelena; Drori, Elyashiv

    2012-10-01

    We report the possibility to modify the wetting properties of the surfaces of a diversity of seeds including: lentils (Lens culinaris), beans (Phaseolus vulgaris) and wheat (Triticum, species C9) by cold radiofrequency air plasma treatment. Air plasma treatment leads to the dramatic decrease in the apparent contact angle. Moreover, the speed of germination and yield (germination rate) of seeds can be modified by preliminary plasma treatment. The change in the wetting properties of seeds is at least partially due to oxidation of their surface under plasma treatment. Significant growth of the peaks corresponding to the nitrogen containing groups in the mass spectra of air plasma treated seeds was registered by TOF-SIMS spectroscopy.

  18. Seed germination conditions and implications for establishment of an epiphyte, Aechmea bracteata (Bromeliaceae)

    Microsoft Academic Search

    Laurel K. Goode; Michael F. Allen

    2009-01-01

    Aechmea bracteata is a common epiphytic bromeliad found in symbiosis with many other species throughout tropical forests of Mexico and south\\u000a through Panama. Given its importance and distribution in these forests, we asked how may A. bracteata be restored to areas where they have thrived in the past? We first investigated seed viability and response of seed germination\\u000a to temperature,

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

    Microsoft Academic Search

    S. O. Baturin

    2009-01-01

    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

  20. Digital imaging information technology applied to seed germination testing. A review

    Microsoft Academic Search

    Antonio Dell’ Aquila

    2009-01-01

    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

  1. Digital Imaging Information Technology Applied to Seed Germination Testing: A Review

    Microsoft Academic Search

    Antonio Dell’ Aquila

    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

  2. Seed development and maturation in Phaseolus vulgaris I. Ability to germinate and to tolerate desiccation

    Microsoft Academic Search

    A. J. Sanhewe; R. H. Ellis

    1996-01-01

    The onset and development of both the ability to ger- minate and to tolerate rapid enforced desiccation were investigated during the development and maturation of seeds of bean {Phaseolus vulgaris L.) at different temperatures and also after different slow-drying treatments. The onset of germinability occurred when seeds were less than half-filled in the absence of both a post-ovule abscission programme

  3. Germination and soil seed bank traits of Podocarpus angustifolius (Podocarpaceae): an endemic tree species from Cuban rain forests.

    PubMed

    Ferrandis, Pablo; Bonilla, Marta; Osorio, Licet del Carmen

    2011-09-01

    Podocarpus angustifolius is an endangered recalcitrant-seeded small tree, endemic to mountain rain forests in the central and Pinar del Río regions in Cuba. In this study, the germination patterns of P. angustifolius seeds were evaluated and the nature of the soil seed bank was determined. Using a weighted two-factor design, we analyzed the combined germination response to seed source (i.e. freshly matured seeds directly collected from trees versus seeds extracted from soil samples) and pretreatment (i.e. seed water-immersion for 48h at room temperature). Germination was delayed for four weeks (= 30 days) in all cases, regardless of both factors analyzed. Moreover, nine additional days were necessary to achieve high germination values (in the case of fresh, pretreated seeds). These results overall may indicate the existence of a non-deep simple morphophysiological dormancy in P. angustifolius seeds. The water-immersion significantly enhanced seed germination, probably as a result of the hydration of recalcitrant seeds. Although germination of seeds extracted from soil samples was low, probably due to aging and pathogen effects throughout the time of burial, the study revealed the existence of a persistent soil seed bank (at least short-termed) of approximately 42 viable seeds per m2 in the upper 10cm of soil. Such a record is noteworthy since references to persistent soil seed banks in recalcitrant-seeded species are scarce in the literature. The population consequences derived from the formation of persistent soil seed banks in this endangered species are discussed. PMID:22017112

  4. Essential role of urease in germination of nitrogen-limited Arabidopsis thaliana seeds.

    PubMed Central

    Zonia, L E; Stebbins, N E; Polacco, J C

    1995-01-01

    In Arabidopsis thaliana, urease transcript levels increased sharply between 2 and 4 d after germination (DAG) and were maintained at maximal levels until at least 8 DAG. Seed urease specific activity declined upon germination but began to increase in seedlings 2 DAG, reaching approximately 75% of seed activity by 8 DAG. Urea levels showed a small transient increase 1 DAG and then approximately paralleled urease activity, reaching maximal levels at approximately 9 DAG. Urease inhibition with phenylphosphorodiamidate resulted in a 2- to 4-fold increase in urea levels throughout seedling development. Arginine pools (0-8 DAG) changed approximately in parallel with the urea pool. Consistent with arginine being a major source of urea, arginase activity increased 10-fold in the interval 0 to 6 DAG. Allopurinol, a xanthine dehydrogenase inhibitor, had no effect on urea levels up to 3 DAG but reduced the urea pool by 30 to 40% during the interval 5 to 8 DAG, suggesting that purine degradation contributed to the urea pool well after germination, if at all. in aged Arabidopsis seeds, there was correlation between phenylphosphorodiamidate inactivation of urease and germination inhibition, the latter overcome by NH4NO3 or amino acids. Since urease activity, urea precursor, and urea increase in young seedlings, and since urease inactivation results in a nitrogen-reversible inhibition of germination, we propose that urease recycles urea-nitrogen in the seedling. PMID:7770520

  5. Seed Germination Ecology of Feather Lovegrass [Eragrostis tenella (L.) Beauv. Ex Roemer & J.A. Schultes

    PubMed Central

    Chauhan, Bhagirath S.

    2013-01-01

    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

  6. Proteomics of Arabidopsis Seed Germination. A Comparative Study of Wild-Type and Gibberellin-Deficient Seeds1

    PubMed Central

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

    2002-01-01

    We examined the role of gibberellins (GAs) in germination of Arabidopsis seeds by a proteomic approach. For that purpose, we used two systems. The first system consisted of seeds of the GA-deficient ga1 mutant, and the second corresponded to wild-type seeds incubated in paclobutrazol, a specific GA biosynthesis inhibitor. With both systems, radicle protrusion was strictly dependent on exogenous GAs. The proteomic analysis indicated that GAs do not participate in many processes involved in germination sensu stricto (prior to radicle protrusion), as, for example, the initial mobilization of seed protein and lipid reserves. Out of 46 protein changes detected during germination sensu stricto (1 d of incubation on water), only one, corresponding to the cytoskeleton component ?-2,4 tubulin, appeared to depend on the action of GAs. An increase in this protein spot was noted for the wild-type seeds but not for the ga1 seeds incubated for 1 d on water. In contrast, GAs appeared to be involved, directly or indirectly, in controlling the abundance of several proteins associated with radicle protrusion. This is the case for two isoforms of S-adenosyl-methionine (Ado-Met) synthetase, which catalyzes the formation of Ado-Met from Met and ATP. Owing to the housekeeping functions of Ado-Met, this event is presumably required for germination and seedling establishment, and might represent a major metabolic control of seedling establishment. GAs can also play a role in controlling the abundance of a ?-glucosidase, which might be involved in the embryo cell wall loosening needed for cell elongation and radicle extension. PMID:12068122

  7. Genome-wide association mapping unravels the genetic control of seed germination and vigor in Brassica napus

    PubMed Central

    Hatzig, Sarah V.; Frisch, Matthias; Breuer, Frank; Nesi, Nathalie; Ducournau, Sylvie; Wagner, Marie-Helene; Leckband, Gunhild; Abbadi, Amine; Snowdon, Rod J.

    2015-01-01

    Rapid and uniform seed germination is a crucial prerequisite for crop establishment and high yield levels in crop production. A disclosure of genetic factors contributing to adequate seed vigor would help to further increase yield potential and stability. Here we carried out a genome-wide association study in order to define genomic regions influencing seed germination and early seedling growth in oilseed rape (Brassica napus L.). A population of 248 genetically diverse winter-type B. napus accessions was genotyped with the Brassica 60k SNP Illumina genotyping array. Automated high-throughput in vitro phenotyping provided extensive data for multiple traits related to germination and early vigor, such as germination speed, absolute germination rate and radicle elongation. The data obtained indicate that seed germination and radicle growth are strongly environmentally dependent, but could nevertheless be substantially improved by genomic-based breeding. Conditions during seed production and storage were shown to have a profound effect on seed vigor, and a variable manifestation of seed dormancy appears to contribute to differences in germination performance in B. napus. Several promising positional and functional candidate genes could be identified within the genomic regions associated with germination speed, absolute germination rate, radicle growth and thousand seed weight. These include B. napus orthologs of the Arabidopsis thaliana genes SNOWY COTYLEDON 1 (SCO1), ARABIDOPSIS TWO-COMPONENT RESPONSE REGULATOR (ARR4), and ARGINYL-t-RNA PROTEIN TRANSFERASE 1 (ATE1), which have been shown previously to play a role in seed germination and seedling growth in A. thaliana. PMID:25914704

  8. Genome-wide association mapping unravels the genetic control of seed germination and vigor in Brassica napus.

    PubMed

    Hatzig, Sarah V; Frisch, Matthias; Breuer, Frank; Nesi, Nathalie; Ducournau, Sylvie; Wagner, Marie-Helene; Leckband, Gunhild; Abbadi, Amine; Snowdon, Rod J

    2015-01-01

    Rapid and uniform seed germination is a crucial prerequisite for crop establishment and high yield levels in crop production. A disclosure of genetic factors contributing to adequate seed vigor would help to further increase yield potential and stability. Here we carried out a genome-wide association study in order to define genomic regions influencing seed germination and early seedling growth in oilseed rape (Brassica napus L.). A population of 248 genetically diverse winter-type B. napus accessions was genotyped with the Brassica 60k SNP Illumina genotyping array. Automated high-throughput in vitro phenotyping provided extensive data for multiple traits related to germination and early vigor, such as germination speed, absolute germination rate and radicle elongation. The data obtained indicate that seed germination and radicle growth are strongly environmentally dependent, but could nevertheless be substantially improved by genomic-based breeding. Conditions during seed production and storage were shown to have a profound effect on seed vigor, and a variable manifestation of seed dormancy appears to contribute to differences in germination performance in B. napus. Several promising positional and functional candidate genes could be identified within the genomic regions associated with germination speed, absolute germination rate, radicle growth and thousand seed weight. These include B. napus orthologs of the Arabidopsis thaliana genes SNOWY COTYLEDON 1 (SCO1), ARABIDOPSIS TWO-COMPONENT RESPONSE REGULATOR (ARR4), and ARGINYL-t-RNA PROTEIN TRANSFERASE 1 (ATE1), which have been shown previously to play a role in seed germination and seedling growth in A. thaliana. PMID:25914704

  9. Cryopreservation of lipid-rich seeds: effect of moisture content and cooling rate on germination.

    PubMed

    González-Benito, E M; Pérez-García, F

    2001-01-01

    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

  10. Effects of temperature, pre-chilling and light on seed germination of Withania somnifera; a high value medicinal plant

    Microsoft Academic Search

    L. Kambizi; P. O. Adebola; A. J. Afolayan

    2006-01-01

    Withania somnifera is under intensive utilization because of its wide ranging medicinal potential. Self-propagation of this species is by seed. In an effort to improve and promote the cultivation of this over-exploited medicinal herb, the effects of temperature and light on the germination of its seeds were investigated. Germination was found to be temperature and light-dependent. Although seed viability was

  11. Seed priming of native ornamental species to improve the rate and uniformity of germination in modern greenhouse operations

    E-print Network

    Finnerty, Terry Lee

    1990-01-01

    production efficiency of perennials in commercial greenhouses; and (3) to determine if priming could be used to bypass the stratification requirements of seeds of three Aquilegia species. Priming Lupinus texensis seeds, scarified or nonscarified, in salt... shock. Priming was not an effective pretreatment for bypassing the stratification requirements of Aquilegia species. The most significant effect of priming was to improve the germination of stratified seeds. At 20oC, germination was higher between...

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

    PubMed Central

    Chen, Hao; Zhang, Jingyu; Neff, Michael M.; Hong, Suk-Whan; Zhang, Huiyong; Deng, Xing-Wang; Xiong, Liming

    2008-01-01

    Seed germination is regulated by endogenous hormonal cues and external environmental stimuli such as water, low temperature, and light. After germination, the young seedling must rapidly establish its root system and the photoautotrophic capability appropriate to its surrounding environment. Light and the phytohormone abscisic acid (ABA) both regulate seed germination and seedling development, although how light and ABA signals are integrated at the molecular level is not understood. Here, we found that the previously described light-signaling component HY5 also mediates ABA response in seed germination, early seedling growth, and root development in Arabidopsis. HY5 binds to the promoter of the transcription factor ABI5 gene with high affinity and is required for the expression of ABI5 and ABI5-targeted late embryogenesis-abundant genes in seeds. Chromatin immunoprecipitation also indicated that the binding of HY5 to the ABI5 promoter is significantly enhanced by ABA. Overexpression of ABI5 restores ABA sensitivity in hy5 and results in enhanced light responses and shorter hypocotyls in the wild type. Our studies identified an unexpected mode of light and ABA signal integration that may help young seedlings better adapt to environmental stresses. PMID:18332440

  13. Ontogeny of glyoxysomes in maturing and germinated cotton seeds—a morphometric analysis

    Microsoft Academic Search

    Christine M. Kunce; Richard N. Trelease; Diane C. Doman

    1984-01-01

    Morphometric procedures were used with light and electron microscopy to examine glyoxysome number, volume, shape and distribution as well as mesophyll cell volume, in cotyledons of mature (50 d postanthesis), imbibed (5h) and germinated (24 and 37 h) cotton (Gossypium hirsutum L.) seeds. Additionally, activities of five glyoxysomal marker enzymes in cotyledon extracts were assayed at each of the above

  14. 14-3-3 adaptor proteins are intermediates in ABA signal transduction during barley seed germination

    E-print Network

    Quatrano, Ralph S.

    14-3-3 adaptor proteins are intermediates in ABA signal transduction during barley seed germination that abscisic acid (ABA) affects both expression and protein levels of five 14-3-3 isoforms in embryonic barley under the control of ABA, but that they control ABA action as well. Keywords: 14-3-3, barley, ABA

  15. Starch grain breakdown in cotyledon cells of germinating mung bean seeds.

    PubMed

    Harris, N

    1976-01-01

    Ultrastructural aspects of the breakdown of starch grains during the mobilisation of reserves in Phaseolus aureus Roxb. seed germination are described. The starch grains show erosion from within leading to the formation of a hollow shell. The erosion is accompanied by intrusion of cytoplasm into the shell. No evidence of a vesicular transport system to or from the eroding face was found. PMID:24430969

  16. Sulfuric acid and hot water treatments enhance ex vitro and in vitro germination of Hibiscus seed

    Microsoft Academic Search

    Hamidou F. Sakhanokho

    2009-01-01

    Seeds of Hibiscus dasycalyx S. F. Blake and Shiller, a federally listed candidate endangered species and native to North America and two variants of Hibiscus acetosella Welw. ex. Hiern were scarified using sulfuric acid and hot water. The effects of the scarification methods on in vitro and ex vitro germination in both species were evaluated. Sulfuric acid scarification was very

  17. COMPARATIVE EFFECTS OF NACL AND SEASALT ON SEED GERMINATION OF COASTAL HALOPHYTES

    Microsoft Academic Search

    ABDUL HAMEED; MUHAMMAD ZAHEER AHMED; MUHAMMAD AJMAL KHAN

    2006-01-01

    The coastal and near coastal habitats of Karachi, Pakistan are characterized by dominant stands of perennial halophytes like Aeluropus lagopoides, Desmostachya bipinnata, Haloxylon stocksii and Suaeda fruticosa. Experiments were carried out to investigate comparative effects of NaCl and seasalt salinity on both rate and final seed germination of these species. Salinity tolerance range of halophytes varied among species and also

  18. Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)

    Microsoft Academic Search

    Derrick D. Cooper; Nate Hough-Snee

    2011-01-01

    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

  19. Perigynium Removal Improves Seed Germination in Awl-Fruit Sedge (Carex stipata)

    Microsoft Academic Search

    Derrick D. Cooper; Nate Hough-Snee

    2011-01-01

    :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

  20. Mycorrhizal fungi of Vanilla: diversity, specificity and effects on seed germination and plant growth

    Microsoft Academic Search

    Andrea Porras-Alfaro; Paul Bayman

    2007-01-01

    Mycorrhizal fungi are essential for the germination of orchid seeds. However, the specificity of orchids for their mycorrhizal fungi and the effects of the fungi on orchid growth are controversial. Mycorrhizal fungi have been studied in some tem- perate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function

  1. Germination of stored and scarified seeds of Passiflora caerulea L. (Passifloraceae)

    Microsoft Academic Search

    G. M. Mendiondo; M. T. Amela García

    2009-01-01

    This work evaluates the influence of storage and scarification in the germination of Passiflora caerulea L., in order to acquire the necessary knowledge to cultivate this economically important species. Seeds stored one month under different conditions (no storage, fermentation, desiccation) were submitted to various pre?treatments (aril removal, mechanical and chemical scarification or combinations of these). Emergence was recorded periodically for

  2. Seed germination-influencing bioactive secondary metabolites secreted by the endophyte Cladosporium cladosporioides LWL5.

    PubMed

    Waqas, Muhammad; Khan, Abdul Latif; Ali, Liaqat; Kang, Sang-Mo; Kim, Yoon-Ha; Lee, In-Jung

    2013-01-01

    The present study was aimed to isolate bioactive metabolites produced by a fungal endophyte from Helianthus annuus, Capsicum annuum, and Cucumis sativus and to assess their role in seed germination. Culture filtrate of the endophyte HA-3B from H. annuus was significantly inhibitory towards the germination and growth of lettuce seeds. HA-3B was identified as Cladosporium cladosporioides LWL5 through molecular techniques. Different concentrations (100, 500 and 1000 ppm) of the ethyl acetate extract obtained from the culture inhibited the lettuce seed germination. The extract was subjected to column chromatography and a bioassay-guided isolation method, which yielded compounds 1, 2 and an oily fraction. The oily fraction, subjected to fractionation and spectroscopic techniques, resulted in the identification of 31 different constituents. Compounds 1 and 2 were identified and characterized through MS and NMR spectroscopic techniques as benzoic acid. The bioassay results showed that this compound significantly inhibited the growth and germination of lettuce seeds. In conclusion, assessing the role of endophytes harboring essential crop plants can help us to develop potentially eco-friendly herbicides. PMID:24352011

  3. The ReEstablishment of Desiccation Tolerance in Germinated Arabidopsis thaliana Seeds and Its Associated Transcriptome

    Microsoft Academic Search

    Julio Maia; Bas J. W. Dekkers; Nicholas J. Provart; Wilco Ligterink; Henk W. M. Hilhorst

    2011-01-01

    The combination of robust physiological models with “omics” studies holds promise for the discovery of genes and pathways linked to how organisms deal with drying. Here we used a transcriptomics approach in combination with an in vivo physiological model of re-establishment of desiccation tolerance (DT) in Arabidopsis thaliana seeds. We show that the incubation of desiccation sensitive (DS) germinated Arabidopsis

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

    Microsoft Academic Search

    Peter A. Van Zandt; Susan Mopper

    2004-01-01

    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.

  5. DEVELOPMENT OF A SCREENING SYSTEM FOR MICRORNAS IN GERMINATING ARABIDOPSIS SEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    MicroRNAs are key regulatory molecules that play critical roles in developmental processes in plants and animals. To gain a better understanding of the regulation of gene expression in seed germination, an efficient screening system was developed to examine microRNAs present during various stages o...

  6. Effects of fungal metabolites on the germination of sweet fennel (Foeniculum vulgare Mill.) seeds.

    PubMed

    Sharma, A K; Sharma, K D

    1983-06-01

    The metabolites of some test fungi adversely affected the seed germination. The maximum reduction was caused by a culture filtrate of Penicillium citrinum followed by Fusarium moniliforme and F. equiseti, while the minimum was caused by Mucor sp. A gradual increase in effective metabolite production was observed by all the fungi up to 15 days. PMID:6623513

  7. Effect of surface roughness on inactivation of Escherichia coli O157:H7 87-23 by new organic acid-surfactant combinations on alfalfa, broccoli, and radish seeds.

    PubMed

    Fransisca, Lilia; Feng, Hao

    2012-02-01

    Surface roughness has been reported as one of the factors affecting microbial attachment and removal. Seed surfaces are complex, and different seed varieties have different surface topographies. As a result, a sanitizer effective in eliminating pathogenic bacteria on one seed may not be as effective when applied to another seed. The objectives of this research were (i) to investigate the efficacy of malic acid and thiamine dilaurylsulfate (TDS) combined treatments for inactivation of E. coli O157:H7 strain 87-23 on alfalfa, broccoli, and radish seeds, (ii) to quantify surface roughness of the seeds, and (iii) to determine the correlation between microbial removal and surface roughness. The surface roughness of each seed type was measured by confocal laser scanning microscopy (CLSM) and surface profilometry. Surface roughness (Ra) values of the seeds were then calculated from CLSM data. Seeds inoculated with E. coli O157:H7 87-23 were washed for 20 min in malic acid and TDS solutions and rinsed for 10 min in tap water. Radish seeds had the highest Ra values, followed by broccoli and alfalfa seeds. A combination of 10% malic acid and 1% TDS was more effective than 20,000 ppm of Ca(OCl)(2) for inactivation of E. coli O157:H7 87-23 on broccoli seeds, while the inactivation on radish and alfalfa seeds was not significantly different compared with the 20,000-ppm Ca(OCl)(2) wash. Overall, a negative correlation existed between the seeds' Ra values and microbial removal. Different seeds had different surface roughness, contributing to discrepancies in the ability of the sanitizers to eliminate E. coli O157:H7 87-23 on the seeds. Therefore, the effectiveness of one sanitizer on one seed type should not be translated to all seed varieties. PMID:22289586

  8. Preliminary studies on allelopatic effect of some woody plants on seed germination of rye-grass and tall fescue.

    PubMed

    Arouiee, H; Nazdar, T; Mousavi, A

    2010-11-01

    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

  9. Nitrogen effects on seed germination and seedling growth

    Microsoft Academic Search

    THOMAS A. MONACO; CHARLES T. MACKOWN; DOUGLAS A. JOHNSON; THOMAS A. JONES; JEANETTE M. NORTON; JAY B. NORTON; MARGARET G. REDINBAUGH

    2003-01-01

    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

  10. Seed germination in Gaultheria antipoda, G. depressa, and Pernettya macrostigma

    Microsoft Academic Search

    Peter Bannister

    1990-01-01

    The germination of the native ericaceous species, Gaultheria antipoda, G. depressa, and Pernettya macrostigma was found to be stimulated by light, and little affected by low temperature pretreatment. This behaviour is very similar to that reported for ericaceous dwarf shrubs in north-western Europe.

  11. The Potential of Algarrobo (Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions.

    PubMed

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75 % germination at 300 mM NaCl, followed by 50 % germination at 450 mM NaCl and 30 % germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97 % at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils. PMID:25894272

  12. The Potential of Algarrobo ( Prosopis chilensis (Mol.) Stuntz) for Regeneration of Desertified Soils: Assessing Seed Germination Under Saline Conditions

    NASA Astrophysics Data System (ADS)

    Westphal, Claus; Gachón, Paloma; Bravo, Jaime; Navarrete, Carlos; Salas, Carlos; Ibáñez, Cristian

    2015-07-01

    Due to their multipurpose use, leguminous trees are desirable for the restoration of degraded ecosystems. Our aim was to investigate seed germination of the leguminous tree Prosopis chilensis in response to salinity, one of the major abiotic challenges of desertified soils. Germination percentages of seed from 12 wild P. chilensis populations were studied. Treatments included four aqueous NaCl concentrations (150, 300, 450, and 600 mM). In each population, the highest germination percentage was seen using distilled water (control), followed closely by 150 mM NaCl. At 300 mM NaCl or higher salt concentration, germination was progressively inhibited attaining the lowest value at 450 mM NaCl, while at 600 mM NaCl germination remained reduced but with large variation among group of samples. These results allowed us to allocate the 12 groups from where seeds were collected into three classes. First, the seeds from Huanta-Rivadavia showed the lowest percent germination for each salt condition. The second group was composed of moderately salt-tolerant seeds with 75 % germination at 300 mM NaCl, followed by 50 % germination at 450 mM NaCl and 30 % germination at 600 mM NaCl. The third group from Maitencillo and Rapel areas was the most salt tolerant with an impressive seed germination level of 97 % at 300 mM NaCl, 82 % at 450 mM NaCl, and 42 % at 600 mM NaCl. Our results demonstrate that P. chilensis seeds from these latter localities have an increased germination capability under saline stress, confirming that P. chilensis is an appropriate species to rehabilitate desertified soils.

  13. Genotyping of Endosperms to Determine Seed Dormancy Genes Regulating Germination Through Embryonic, Endospermic, or Maternal Tissues in Rice

    PubMed Central

    Gu, Xing-You; Zhang, Jinfeng; Ye, Heng; Zhang, Lihua; Feng, Jiuhuan

    2014-01-01

    Seed dormancy is imposed by one or more of the embryo, endosperm, and maternal tissues that belong to two generations and represent two ploidy levels. Many quantitative trait loci (QTL) have been identified for seed dormancy as measured by gross effects on reduced germination rate or delayed germination in crop or model plants. This research developed an endosperm genotype?based genetic approach to determine specific tissues through which a mapped QTL regulates germination using rice as a model. This approach involves testing germination velocity for partially after-ripened seeds harvested from single plants heterozygous for a tested QTL and genotyping endosperms from individual germinated and nongerminated seeds with a codominant DNA marker located on the QTL peak region. Information collected about the QTL includes genotypic frequencies in germinated and/or nongerminated subpopulations; allelic frequency distributions during a germination period; endosperm or embryo genotypic differences in germination velocity; and genotypic frequencies for gametes involved in the double fertilization to form the sampled seeds. Using this approach, the seed dormancy loci SD12, SD1-2, and SD7-1 were determined to regulate germination through the embryo, endosperm, and maternal tissues, respectively; SD12 and SD1-2 acted additively on germination velocity in the offspring tissues; and SD12 also was associated with the preferential fertilization of male gametes in rice. This new genetic approach can be used to characterize mapped genes/QTL for tissue-specific functions in endospermic seeds and for marker-assisted selection of QTL alleles before or immediately after germination in crop breeding. PMID:25480961

  14. Expression of genes associated with the biosynthetic pathways of abscisic acid, gibberellin, and ethylene during the germination of lettuce seeds.

    PubMed

    Clemente, A C S; Guimarães, R M; Martins, D C; Gomes, L A A; Caixeta, F; Reis, R G E; Rosa, S D V F

    2015-01-01

    Seed germination and dormancy are complex phenomena that are controlled by many genes and environmental factors. Such genes are indicated by phytohormones that interact with each other, and may cause dormancy or promote seed germination. The objective of this study was to investigate gene expression associated with the biosynthetic pathways of abscisic acid (ABA), gibberellic acid (GA), and ethylene (ET) in dormant and germinated lettuce seeds. The expressions of LsNCED, LsGA3ox1, and ACO-B were evaluated in germinating and dormant seeds from the cultivars Everglades, Babá de Verão, Verônica, Salinas, Colorado, and Regina 71. The expressions of LsNCED, LsGA3ox1, and ACO-B were related to the biosynthesis of ABA, GA, and ET, respectively; therefore, the presence of these substances depends on genotype. LsNCED expression only occurred in dormant seeds, and was connected to dormancy. LsGA3ox1expression only occurred in germinated seeds, and was connected to germination. The ACO-B gene was involved in ET biosynthesis, and was expressed differently in germinated and dormant seeds, depending on the genotype, indicating different functions for different characteristics. Furthermore, sensitivity to phytohormones appeared to be more important than the expression levels of LsNCED, LsGA3ox1, or ACO-B. PMID:25966245

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

    PubMed

    Arnold, Sven; Kailichova, Yolana; Baumgartl, Thomas

    2014-01-01

    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

  16. Characterization of a radish introgression carrying the Ogura fertility restorer gene Rfo in rapeseed, using the Arabidopsis genome sequence and radish genetic mapping

    Microsoft Academic Search

    Sandra Giancola; Sylvie Marhadour; Sophie Desloire; Vanessa Clouet; Hélène Falentin-Guyomarc'h; Wassila Laloui; Cyril Falentin; Georges Pelletier; Michel Renard; Abdelhafid Bendahmane; Régine Delourme; Françoise Budar

    2003-01-01

    The radish Rfo gene restores male fertility in radish or rapeseed plants carrying Ogura cytoplasmic male-sterility. This system was first discovered in radish and was transferred to rapeseed for the production of F1 hybrid seeds. We aimed to identify the region of the Arabidopsis genome syntenic to the Rfo locus and to characterize the radish introgression in restored rapeseed. We

  17. An allelopathic substance exuded from germinating watermelon seeds

    Microsoft Academic Search

    Midori Kushima; Hideo Kakuta; Seiji Kosemura; Shosuke Yamamura; Kosumi Yamada; Kaori Yokotani-Tomita; Koji Hasegawa

    1998-01-01

    When watermelon seeds were cultured in a Petri dish together with amaranth, barnyard grass, cockscomb, lettuce or tomato seeds, the shoot growth of amaranth and cockscomb was markedly promoted, whereas the shoot growth of lettuce and tomato was inhibited. The shoot growth of barnyard grass was not affected. These results suggest that plant-selective allelopathic substance(s) affecting the shoot growth of

  18. The effects of Biozyme on the germination and emergence of bean (Phaseolus vulgaris L.) and sweet corn (Zea mays L.) seeds under suboptimal temperatures, pesticide overdose, and salinity stress 

    E-print Network

    Campos Cruz, Armando

    1994-01-01

    synergystically on rate and percent germination. Biozyme increased percent germination, but did not hasten germination rate or days to 50% germination. Biozyme treatment of bean seeds helped them overcome pesticide overdose stress. Aerobic respiration was measured...

  19. Biological effects of low energy nitrogen ion implantation on Jatropha curcas L. seed germination

    NASA Astrophysics Data System (ADS)

    Xu, Gang; Wang, Xiao-teng; Gan, Cai-ling; Fang, Yan-qiong; Zhang, Meng

    2012-09-01

    To explore the biological effects of nitrogen ion beam implantation on dry Jatropha curcas seed, a beam of N+ with energy of 25 keV was applied to treat the dry seed at six different doses. N+ beam implantation greatly decreased germination rate and seedling survival rate. The doses within the range of 12 × 1016 to 15 × 1016 ions cm-2 severely damaged the seeds: total antioxidant capacity (TAC), germination rate, seedling survival rate, reduced ascorbate acid (HAsA) and reduced glutathione (GSH) contents, and most of the tested antioxidases activity (i.e. catalase (CAT), ascorbate peroxidase (APX) and superoxide dismutase (SOD)) reached their lowest levels. At a dose of 18 × 1016 ion cm-2, biological repair took place: moderate increases were found in TAC, germination rate, seedling survival rate, HAsA and GSH contents, and some antioxidant enzyme activities (i.e. CAT, APX, SOD and GPX). The dose of 18 × 1016 ions cm-2 may be the optimum dose for use in dry J. curcas seed mutation breeding. CAT, HAsA and GSH contributed to the increase of TAC, but CAT was the most important. POD performed its important role as seed was severely damaged. The main role of the HAsA-GSH cycle appeared to be for regeneration of HAsA.

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

    PubMed Central

    Kos, Martijn; Poschlod, Peter

    2007-01-01

    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

  1. The dual role of temperature in the regulation of the seasonal changes in dormancy and germination of seeds of Polygonum persicaria L

    Microsoft Academic Search

    Harro J. Bouwmeester; Cees M. Karssen

    1992-01-01

    The role of temperature in the regulation of seasonal changes in dormancy and germination was studied in seeds of Polygonum persicaria. Seeds were buried in the field and under controlled conditions. Portions of seeds were exhumed at regular intervals and germination was tested over a range of conditions. Seeds of P. persicaria exhibited a seasonal dormancy pattern that clearly showed

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

    PubMed Central

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

    2012-01-01

    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

  3. Role of Ethylene in Lactuca sativa cv `Grand Rapids' Seed Germination

    PubMed Central

    Abeles, Fred B.

    1986-01-01

    Promotion of thermoinhibited (30°C) lettuce (Lactuca sativa cv `Grand Rapids') seed germination by ethylene is similar to the action of the gas in other hormonal systems. Ethylene was more active than propylene and ethane was inactive. An inhibitor of ethylene production, aminoethoxy-vinylglycine, reduced ethylene evolution and germination. Inhibitors of ethylene action such as, 5-methyl-7-chloro-4-ethoxycarbonylmethoxy-2,1,3-benzothiadiazole, 2,5-norbornadiene, and silver thiosulfate inhibited germination and the effect was reversed by the addition of ethylene to the gas phase. The action of ethylene appears to be due to the promotion of radial cell expansion in the embryonic hypocotyl. The action of N6-benzyladenine and fusiccocin, which also overcome thermoinhibition, appears to be due to a promotion of hypocotyl elongation. None of the germination promoters studied appeared to function by lowering the mechanical resistance of the endosperm to embryonic growth. Data presented here are consistent with the view that ethylene plays a role in lettuce seed germination under thermoinhibited and normal conditions. PMID:16664902

  4. Role of Ethylene in Lactuca sativa cv ;Grand Rapids' Seed Germination.

    PubMed

    Abeles, F B

    1986-07-01

    Promotion of thermoinhibited (30 degrees C) lettuce (Lactuca sativa cv ;Grand Rapids') seed germination by ethylene is similar to the action of the gas in other hormonal systems. Ethylene was more active than propylene and ethane was inactive. An inhibitor of ethylene production, aminoethoxy-vinylglycine, reduced ethylene evolution and germination. Inhibitors of ethylene action such as, 5-methyl-7-chloro-4-ethoxycarbonylmethoxy-2,1,3-benzothiadiazole, 2,5-norbornadiene, and silver thiosulfate inhibited germination and the effect was reversed by the addition of ethylene to the gas phase. The action of ethylene appears to be due to the promotion of radial cell expansion in the embryonic hypocotyl. The action of N6-benzyladenine and fusiccocin, which also overcome thermoinhibition, appears to be due to a promotion of hypocotyl elongation. None of the germination promoters studied appeared to function by lowering the mechanical resistance of the endosperm to embryonic growth. Data presented here are consistent with the view that ethylene plays a role in lettuce seed germination under thermoinhibited and normal conditions. PMID:16664902

  5. Seed germination in response to diurnal fluctuations of temperature

    Microsoft Academic Search

    K. Thompson; J. P. Grime; G. Mason

    1977-01-01

    DIURNAL fluctuations in temperature may initiate or accelerate germination in certain flowering plants1-6, and the effectiveness of the stimulus varies according to the amplitude of fluctuation7 and the presence or absence of light8. Attempts3,6 to assess the adaptive significance of the phenomenon, however, have been limited by the scarcity of data for species of contrasted ecology. We report here an

  6. Dung beetles as secondary seed dispersers: impact on seed predation and germination

    Microsoft Academic Search

    VIRGINIA E. SHEPHERD; COLIN A. CHAPMAN

    1998-01-01

    Dispersal of seeds away from the parent plant may facilitate escape from density-dependent seed mortality. However, many post-dispersal events can have a profound influence on the survival of dispersed seeds. By incorporating seeds in the dung that dung beetles process for consumption and oviposition, dung beetles could enhance seed survival if they remove seeds from areas of high pre- dation

  7. Identification of genes related to germination in aged maize seed by screening natural variability.

    PubMed

    Revilla, P; Butrón, A; Rodríguez, V M; Malvar, R A; Ordás, A

    2009-01-01

    Ageing reduces vigour and viability in maize inbred lines due to non-heritable degenerative changes. Besides non-heritable genetic changes due to chromosome aberrations and damage in the DNA sequence, heritable changes during maize conservation have been reported. Genetic variability among aged seeds of inbred lines could be used for association studies with seed germination. The objective of this study was to identify genes related to germination in aged seeds. The sweet corn inbred line P39 and the field corn inbred line EP44 were used as plant material. Bulks of living and dead seeds after 20 and 22 years of storage were compared by using simple sequence repeats (SSRs) and, when the bulks differed for a marker, the individual grains were genotyped. Differences between dead and living seeds could be explained by residual variability, spontaneous mutation, or ageing. Variability was larger for chromosome 7 than for other chromosomes, and for distal than for proximal markers, suggesting some relationships between position in the genome and viability in aged seed. Polymorphic SSRs between living and dead seeds were found in six known genes, including pathogenesis-related protein 2, superoxide dismutase 4, catalase 3, opaque endosperm 2, and metallothionein1 that were related to germination, along with golden plant 2. In addition, five novel candidate genes have been identified; three of them could be involved in resistance to diseases, one in detoxification of electrophillic compounds, and another in transcription regulation. Therefore, genetic variability among aged seeds of inbreds was useful for preliminary association analysis to identify candidate genes. PMID:19684106

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

    PubMed

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

    2013-02-01

    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

  9. Effect of saline water on seed germination and early seedling growth of the halophyte quinoa.

    PubMed

    Panuccio, M R; Jacobsen, S E; Akhtar, S S; Muscolo, A

    2014-01-01

    Salinization is increasing on a global scale, decreasing average yields for most major crop plants. Investigations into salt resistance have, unfortunately, mainly been focused on conventional crops, with few studies screening the potential of available halophytes as new crops. This study has been carried out to investigate the mechanisms used by quinoa, a facultative halophytic species, in order to cope with high salt levels at various stages of its development. Quinoa is regarded as one of the crops that might sustain food security in this century, grown primarily for its edible seeds with their high protein content and unique amino acid composition. Although the species has been described as a facultative halophyte, and its tolerance to salt stress has been investigated, its physiological and molecular responses to seawater (SW) and other salts have not been studied. We evaluated the effects of SW and different salts on seed germination, seedling emergence and the antioxidative pathway of quinoa. Seeds were germinated in Petri dishes and seedlings grown in pots with SW solutions (25, 50, 75 and 100 %) and NaCl, CaCl2, KCl and MgCl2 individually, at the concentrations in which they are present in SW. Our results demonstrated that all salts, at lower concentrations, increased the germination rate but not the germination percentages, compared with control (pure water). Conversely, seedlings were differently affected by treatments in respect to salt type and concentration. Growth parameters affected were root and shoot length, root morphology, fresh and dry weight, and water content. An efficient antioxidant mechanism was present in quinoa, activated by salts during germination and early seedling growth, as shown by the activities of antioxidant enzymes. Total antioxidant capacity was always higher under salt stress than in water. Moreover, osmotic and ionic stress factors had different degrees of influence on germination and development. PMID:25139769

  10. Respiratory metabolism in the embryonic axis of germinating pea seed exposed to cadmium.

    PubMed

    Smiri, Moêz; Chaoui, Abdelilah; El Ferjani, Ezzedine

    2009-02-15

    Seeds of pea (Pisum sativum L.) were germinated for 5d by soaking in distilled water or 5mM cadmium nitrate. The relationships among cadmium stress, germination rate, changes in respiratory enzyme activities and carbohydrates mobilization were studied. Two cell fractions were obtained from embryonic axis: (1) mitochondria, used to determine enzyme activities of citric acid cycle and electron transport chain, and (2) soluble, to measure some enzyme activities involved in fermentation and pentose phosphate pathway. Activities of malate- and succinate-dehydrogenases (MDH, SDH) and NADH- and succinate-cytochrome c reductases (NCCR, SCCR) were rapidly inhibited, while cytochrome c oxidase (CCO) was unaltered by cadmium treatment. However, this stimulated the NADPH-generating enzyme activities of the pentose phosphate pathway, glucose-6-phosphate- and 6-phosphogluconate-dehydrogenases (G6PDH, 6PGDH), as well as enzyme activity of fermentation, alcohol dehydrogenase (ADH), with concomitant inhibition in the capacity of enzyme inactivator (INADH). Moreover, Cd restricted carbohydrate mobilization in the embryonic axis. Almost no glucose and less than 7% of control fructose and total soluble sugars were available in the embryo tissues after 5d of exposure to cadmium. Cotyledonary invertase isoenzyme activity was also inhibited by Cd. The results indicate that cadmium induces disorder in the resumption of respiration in germinating pea seeds. The contribution of Cd-stimulated alternative metabolic pathways to compensate for the failure in mitochondrial respiration is discussed in relation to the delay in seed germination and embryonic axis growth. PMID:18760497

  11. The Appearance of New Active Forms of Trypsin Inhibitor in Germinating Mung Bean (Vigna radiata) Seeds.

    PubMed

    Lorensen, E; Prevosto, R; Wilson, K A

    1981-07-01

    Ungerminated seeds of mung bean contain a single major species (F) of trypsin inhibitor with five minor species (A-E) separable on diethylaminoethyl-cellulose. During germination the level of trypsin inhibitory activity decreases from 1.8 units/grams dry weight in ungerminated cotyledons to 1.2 units/grams in cotyledons from seeds germinated 5 days. This decrease is accompanied by major changes in the distribution of inhibitory activity among the inhibitor species. By 48 hours of germination, inhibitor F has largely disappeared with an accompanying rapid increase in inhibitor C. Similarly, though less rapidly, inhibitor E decreases while inhibitor A increases. A similar sequence of changes is found in vitro when purified inhibitor F is incubated with extracts from seeds germinated 96 hours. The combined in vivo and in vitro data suggest a conversion sequence of: F --> E --> C --> A. The in vitro conversion is inhibited by phenylmethyl sulfonyl fluoride but not by iodoacetamide, indicating that at least the initial phases of inhibitor conversion are not catalyzed by the mung bean vicilin peptidohydrolase. PMID:16661895

  12. Germination Characteristics of Polymer-Coated Canola (Brassica napus L.) Seeds Subjected to Moisture Stress at Different Temperatures

    Microsoft Academic Search

    Christian J. Willenborg; Robert H. Gulden; Eric N. Johnson; Steven J. Shirtliffe

    and reduce germination and plant establishment (Sharma, 1976; Hegarty, 1977; Schneider and Gupta, 1985). Polymer coatings have recently been developed to prevent germi- To avoid some of these problems in canola produc- nation and thereby reduce undesirable emergence of fall-seeded ca- tion, alternative seeding dates such as seeding canola in nola (Brassica napus L.) in western Canada. However, recent observa-

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

    Microsoft Academic Search

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

    2004-01-01

    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.

  14. Seed germination ecology of Echinochloa glabrescens and its implication for management in rice (Oryza sativa L.).

    PubMed

    Opeña, Jhoana L; Chauhan, Bhagirath S; Baltazar, Aurora M

    2014-01-01

    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

  15. Interrelations between Carbon Dioxide and Ethylene on the Stimulation of Cocklebur Seed Germination

    PubMed Central

    Esashi, Yohji; Kawabe, Kunimasa; Isuzugawa, Kanji; Ishizawa, Kimiharu

    1988-01-01

    Interrelations between CO2 and C2H4 on promotion of seed germination were examined in more detail at 23°C with presoaked upper seeds of Xanthium pennsylvanicum Wallr. The germination-promoting effect of C2H4 decreased gradually as its application time was delayed during a soaking period, whereas CO2 was most promotive in application at 5 days of soaking, then its effect declined. CO2 and C2H4 were additive in earlier soaking periods and synergistic in later periods. Such changes in germination behavior in response to CO2 and/or C2H4 during a soaking period were closely associated with growth responsiveness of the axial tissues, but not of the cotyledonary ones. Growth responsiveness of axial tissues to CO2 or C2H4 disappeared finally during a soaking period, but their extinct responsiveness to any one of these gases was almost fully restored in the simultaneous presence of the other. The extinct responsiveness to CO2 was partially recovered by a preexposure to C2H4. This suggests that in the later period of soaking, unlike the case in a very early period of soaking, the C2H4-sensitive phase for seed germination precedes the CO2-sensitive phase in which CO2 potentiated axial growth. The restoration of CO2 responsiveness in axial growth occurred not only after C2H4 treatment but also after exposure to 8 or 33°C or after KCN treatment. Thus, secondarily dormant Xanthium seeds could germinate in response to CO2 alone, when they were previously exposed for shortterms not only to C2H4 but also 8°C, 33°C, or KCN. PMID:16665889

  16. Basal Transcription Factor 3 Plays an Important Role in Seed Germination and Seedling Growth of Rice

    PubMed Central

    Wang, Wenyi; Xu, Mengyun; Wang, Ya

    2014-01-01

    BTF3 has been recognized to be involved in plant growth and development. But its function remains mostly unknown during seed germination and seedling stage. Here, we have analyzed OsBTF3-related sequences in Oryza sativa L. subspecies, japonica, which resembles with the conserved domain of a nascent polypeptide associated complex (NAC) with different homologs of OsBTF3 and human BTF3. Inhibition of Osj10gBTF3 has led to considerable morphological changes during seed germination and seedling growth. Germination percentage was not influenced by the application of GA3, ABA, and NaCl but all concentrations caused wild-type (WT) seeds to germinate more rapidly than the RNAi (Osj10gBTF3Ri) transgenic lines. Seedling inhibition was more severe in the Osj10gBTF3Ri seedlings compared with their WT especially when treated with 100 or 200??M GA3; 50% reduction in shoots was observed in Osj10gBTF3Ri seedlings. The expression of Osj3g1BTF3, Osj3g2BTF3 and Osj10gBTF3 was primarily constitutive and generally modulated by NaCl, ABA, and GA3 stresses in both Osj10gBTF3Ri lines and WT at the early seedling stage, suggesting that Osj3g1BTF3 and Osj10gBTF3 are much similar but different from Osj3g2BTF3 in biological function. These results show that OsBTF3 plays an important role in seed germination and seedling growth gives a new perception demonstrating that more multifaceted regulatory functions are linked with BTF3 in plants. PMID:24971328

  17. Potential effects of arboreal and terrestrial avian dispersers on seed dormancy, seed germination and seedling establishment in Ormosia (Papilionoideae) species in Peru

    USGS Publications Warehouse

    Foster, M.S.

    2008-01-01

    The relative effectiveness of arboreal or terrestrial birds at dispersing seeds of Ormosia macrocalyx and O. bopiensis (Fabaceae: Papilionoideae) were studied in south-eastern Peru. Seeds of both species were either scarified, to represent seed condition after dispersal by terrestrial birds, or left intact, to represent seed condition after dispersal by arboreal birds. Seeds were distributed along forest transects, and germination, seedling development and mortality were monitored to determine the successes of the two groups at producing seedlings. Scarified seeds germinated with the early rains of the dry-to-wet-season transition, when erratic rainfall was interspersed with long dry spells. Intact seeds germinated 30 d later when the rain was more plentiful and regular. Intact seeds of O. macrocalyx gave rise to significantly more seedlings (41.1% vs. 25.5%) than did scarified seeds, in part, because significantly more seedlings from scarified seeds (n = 20) than from intact seeds (n = 3) died from desiccation when their radicles failed to enter the dry ground present during the dry-to-wet-season transition. Also, seedlings from scarified seeds were neither larger nor more robust than those from intact seeds despite their longer growing period. Results are consistent with the hypothesis that dispersal effectiveness of arboreal birds, at least for O. macrocalyx, is greater than that of terrestrial birds. Screen-house experiments in which seedlings developed under different watering regimes supported this result. Numbers of seedlings developing from intact and scarified seeds of O. bopiensis did not differ significantly.

  18. Gibberellic acid nitrite stimulates germination of two species of light-requiring seeds via the nitric oxide pathway.

    PubMed

    Jovanovi?, Vladan; Giba, Zlatko; Djokovi?, Dejan; Milosavljevi?, Slobodan; Grubisi?, Dragoljub; Konjevi?, Radomir

    2005-06-01

    We used two species of light-requiring seeds, Paulownia tomentosa, which have absolute light requirement (no germination in darkness), and Stellaria media seeds, which germinate in darkness to a certain extent because of presence of preformed active phytochrome, to obtain results strongly suggesting that gibberellic acid nitrite stimulates seed germination via its capability as a functional NO donor. Exogenous application of gibberellic acid nitrite stimulates gibberellin-insensitive Stellaria media seed germination in darkness as do a wide variety of NO donors. Pure gibberellic acid could replace the light requirement of P. tomentosa seeds, thus enabling them to germinate in darkness. Gibberellic acid nitrite did not have this effect. A stimulative effect from gibberellic acid nitrite could be detected only after exposure of these seeds to short, 10 min, pulse of red light. Taken together, these results suggest that gibberellic activity of gibberellic acid nitrite is lost after nitrosation but, regarding to the presence of -O-NO moiety in the molecule, gibberellic acid nitrite shares stimulative properties in seed germination with other compounds with NO-releasing properties. PMID:16154981

  19. An Increase in Pectin Methyl Esterase Activity Accompanies Dormancy Breakage and Germination of Yellow Cedar Seeds1

    PubMed Central

    Ren, Chengwei; Kermode, Allison R.

    2000-01-01

    Pectin methyl esterase (PME) (EC 3.1.1.11) catalyzes the hydrolysis of methylester groups of cell wall pectins. We investigated the role of this enzyme in dormancy termination and germination of yellow cedar (Chamaecyparis nootkatensis [D. Don] Spach) seeds. PME activity was not detected in dormant seeds of yellow cedar but was induced and gradually increased during moist chilling; high activity coincided with dormancy breakage and germination. PME activity was positively correlated to the degree of dormancy breakage of yellow cedar seeds. The enzyme produced in different seed parts and in seeds at different times during moist chilling, germination, and early post-germinative growth consisted of two isoforms, both basic with isoelectric points of 8.7 and 8.9 and the same molecular mass of 62 kD. The pH optimum for the enzyme was between 7.4 and 8.4. In intact yellow cedar seeds, activities of the two basic isoforms of PME that were induced in embryos and in megagametophytes following dormancy breakage were significantly suppressed by abscisic acid. Gibberellic acid had a stimulatory effect on the activities of these isoforms in embryos and megagametophytes of intact seeds at the germinative stage. We hypothesize that PME plays a role in weakening of the megagametophyte, allowing radicle emergence and the completion of germination. PMID:10982438

  20. Initial Changes in the Transcriptome of Euphorbia esula Seeds Induced to Germinate with a Combination of Constant and Diurnal Alternating Temperatures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We investigated transcriptome changes in Euphorbia esula (leafy spurge) seeds with a focus on the effect of constant and diurnal fluctuating temperature on dormancy and germination. Leafy spurge seeds do not germinate when incubated for 21 days at 20°C constant temperatures, but nearly 30% germinate...

  1. PHYSICOCHEMICAL ANALYSIS AND EFFECT OF DISTILLERY EFFLUENT ON SEED GERMINATION OF WHEAT (Triticum aestivum), PEA (Pisum sativum) AND LADY'S FINGER (Abelmoschus esculentus)

    Microsoft Academic Search

    Sandeep K. Pandey; Pallavi Tyagi; Anil K. Gupta

    A laboratory work was undertaken to assess the waste water quality parameters of treated distillery effluent and their effect of various concentrations like 0%, 25%, 50%, 75% & 100% on seeds germination, speed of germination, peak value and germination value of three selected seeds i.e. Wheat (Triticum aestivum), Pea (Pisum sativm) and Lady's Finger (Abelmoschus esculentus). Where the high value

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

    Microsoft Academic Search

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

    2010-01-01

    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

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

    Microsoft Academic Search

    Gederts Ievinsh

    2007-01-01

    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

  4. Do seed VLCFAs trigger spongy tissue formation in Alphonso mango by inducing germination?

    PubMed

    Shivashankar, Seshadri; Sumathi, Manoharan

    2015-06-01

    Spongy tissue is a physiological disorder in Alphonso mango caused by the inception of germination-associated events during fruit maturation on the tree, rendering the fruit inedible. Inter-fruit competition during active fruit growth is a major contributing factor for the disorder which leads to reduced fat content in spongy tissue affected fruits. This study was, therefore, carried out to determine the possible association between seed fats and ST formation. The study of the fat content during fruit growth showed that it increased gradually from 40 percent fruit maturity. At 70 percent maturity, however, there was a sudden increase of fat content of whole fruit, leading to acute competition and resulting in differential allocation of resources among developing fruits. As a result, the seed in spongy-tissue-affected mature ripe fruit showed a marked drop in the levels of fats and the two very long chain fatty acids (VLCFAs), tetracosanoic acid and hexacosanoic acid together with an increase of linolenic acid and a fall in oleic acid contents, which are known to be key determinants for the initiation of pre-germination events in seed. Subsequently, a rise in the level of cytokinin and gibberellins in ST seed associated with a fall in abscisic acid level clearly signalled the onset of germination. Concurrently, a significant reduction in the ratio of linolenic acid/linoleic acid in pulp led to the loss of membrane integrity, cell death and the eventual formation of spongy tissue. Based on the above, it is concluded that a significant reduction in the biosynthesis of VLCFAs in seeds during fruit growth might trigger pre-germination events followed by a cascade of biochemical changes in the pulp, leading to lipid peroxidation and membrane injury in pulp culminating in ST development. Thus, this study presents crucial experimental evidence to highlight the critical role played by VLCFAs in inducing ST formation in Alphonso mango during the pre-harvest phase of fruit growth. PMID:25963264

  5. Micropropagation of Withania somnifera from germinating seeds and shoot tips

    Microsoft Academic Search

    Jayanti Sen; A. K. Sharma

    1991-01-01

    Shoot multiplication was achieved in vitro from shoot tips of aseptically germinated seedlings of Withania somnifera L. using low concentrations of 6-benzyladenine (BA), viz. 2.2, 4.4 and 8.9 µM. Maximum number of shoots were obtained when 2.3 µM 2,4-dichlorophenoxyacetic acid (2,4-D) or 2.5 µM indolebutyric acid (IBA) was added to medium containing 4.4 µM BA during initiation of shoot multiplication,

  6. Effects of Temperature, Salinity and Seed Age on Induction of Zostera japonica Germination in North America, USA

    EPA Science Inventory

    Seagrasses can colonize unstructured mudflats either through clonal growth or seed germination and survival. Zostera japonica is an introduced seagrass in North America that has rapidly colonized mudflats along the Pacific Coast, leading to active management of the species. Gro...

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

    E-print Network

    Cooke, Todd J.

    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 excision. Unlabeled tryptophan suppressed [14 C]anthranilate conversion into IAA in isolated axes

  8. Physiology, morphology and phenology of seed dormancy break and germination in the endemic Iberian species Narcissus hispanicus (Amaryllidaceae)

    PubMed Central

    Copete, Elena; Herranz, José M.; Ferrandis, Pablo; Baskin, Carol C.; Baskin, Jerry M.

    2011-01-01

    Background and Aims Only very few studies have been carried out on seed dormancy/germination in the large monocot genus Narcissus. A primary aim of this study was to determine the kind of seed dormancy in Narcissus hispanicus and relate the dormancy breaking and germination requirements to the field situation. Methods Embryo growth, radicle emergence and shoot growth were studied by subjecting seeds with and without an emerged radicle to different periods of warm, cold or warm plus cold in natural temperatures outdoors and under controlled laboratory conditions. Key Results Mean embryo length in fresh seeds was approx. 1·31 mm, and embryos had to grow to 2·21 mm before radicle emergence. Embryos grew to full size and seeds germinated (radicles emerged) when they were warm stratified for 90 d and then incubated at cool temperatures for 30 d. However, the embryos grew only a little and no seeds germinated when they were incubated at 9/5, 10 or 15/4 °C for 30 d following a moist cold pre-treatment at 5, 9/5 or 10 °C. In the natural habitat of N. hispanicus, seeds are dispersed in late May, the embryo elongates in autumn and radicles emerge (seeds germinate) in early November; however, if the seeds are exposed to low temperatures before embryo growth is completed, they re-enter dormancy (secondary dormancy). The shoot does not emerge until March, after germinated seeds are cold stratified in winter. Conclusion Seeds of N. hispanicus have deep simple epicotyl morphophysiological dormancy (MPD), with the dormancy formula C1bB(root) – C3(epicotyl). This is the first study on seeds with simple MPD to show that embryos in advanced stages of growth can re-enter dormancy (secondary dormancy). PMID:21335326

  9. Responses to salt stress in Juncus acutus and J. maritimus during seed germination and vegetative plant growth

    Microsoft Academic Search

    Monica Boscaiu; Genoveva Ballesteros; Miguel A. Naranjo; Oscar Vicente; Herminio Boira

    2011-01-01

    Responses to increasing salinity, during seed germination and vegetative plant growth, were studied in two related species of Juncus, J. maritimus and J. acutus. In both species, germination was optimal in the absence of salt, reduced by about 50% in the presence of 200 mM NaCl, and completely inhibited by NaCl concentrations above 300 mM. Previous exposure of the seeds to salt,

  10. Seed characteristics and soil surface patch type interact to affect germination of semi-arid woodland species

    Microsoft Academic Search

    Amber L. Briggs; John W. Morgan

    2011-01-01

    Biological soil crusts are common in many arid and semi-arid regions and they can alter microenvironments which are likely\\u000a to directly and indirectly influence vascular plant establishment. The effect of biological soil crusts on germination is\\u000a also influenced by the biological characteristics of the seeds themselves but rarely have the effects of both crust type and\\u000a seed morphology on germination

  11. Cadmium stress affects seed germination and seedling growth in Sorghum bicolor (L.) Moench by changing the activities of hydrolyzing enzymes

    Microsoft Academic Search

    Saritha V. Kuriakose; M. N. V. Prasad

    2008-01-01

    Seed germination, one of the most important phases in the life cycle of a plant, is highly responsive to existing environment.\\u000a Hydrolyzing enzymes play a major role in the mobilization of food reserves by hydrolyzing carbohydrates, proteins and fats.\\u000a This paper reports on the effect of Cd toxicity on seed germination and the activities of hydrolyzing enzymes, like acid phosphatases

  12. Ameliorative effect of brassinosteroid and ethylene on germination of cucumber seeds in the presence of sodium chloride

    Microsoft Academic Search

    Baolan Wang; Jinli Zhang; Xiuzhi Xia; Wen-Hao Zhang

    Brassinosteroids are a class of plant polyhydroxysteroids with a diverse of functions in plant growth and development, while\\u000a ethylene is a gaseous hormone involved in regulation of numerous physiological processes. To evaluate the roles of BR and\\u000a ethylene in seed germination under conditions of salt stress, effects of 24-Epibrassinolide (EBR) and 1-aminocyclopropane-1-carboxylic\\u000a acid (ACC) on seed germination of cucumber (Cucumis

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

    Microsoft Academic Search

    Besma Ben Dkhil; Mounir Denden

    2010-01-01

    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.

  14. Seed size influence on germination responses to light and temperature of seven pioneer tree species from the Central Amazon.

    PubMed

    Aud, Fabiana F; Ferraz, Isolde D K

    2012-09-01

    In Amazon secondary forests are dominated by pioneer species that typically produce large amounts of small and dormant seeds that are able to form a persistent soil seed bank. Seed dormancy in this group of species is overcome by environmental conditions found in open areas, such as high irradiation or alternating temperatures. Nevertheless, a variety of germination responses to environmental factors is known among pioneers; some of them may germinate in diffuse light or in darkness condition at constant temperature. Seed mass can be considered as one of the factors that promotes this variety. Regarding species with very small seeds, it seems that the trigger for germination is light and for larger seeds temperature alternation may be a more important stimulus. In this study we established a relationship between seed mass and germination response to light and alternating temperature for a group of seven woody pioneer species from the Amazon forest. We found that an increase in seed mass was followed by a decrease in the need for light and an increase in the tolerance to alternating temperatures. Understanding germination strategies may contribute with the knowledge of species coexistence in high diverse environments and also may assist those involved in forest management and restoration. PMID:22886162

  15. Effects of aqueous extracts of Paeonia decomposita seeds on germination and some metabolic activities associated with growth of wheat seedlings.

    PubMed

    Song, Hui-Xing; Liu, Guang-Li; Chen, Qi-Bing

    2012-09-01

    Paeonia decomposita is a perennial deciduous shrub with great ornamental and medicinal values. Unfortunately, the distribution region, population size and individual numbers of P. decomposita rapidly decrease in the wild. It is a particularly rare, highly endangered, protective plant endemic to Southwest China. To understand the causes of seed dormancy of P. decomposita, the effects of aqueous extracts of the seed coat, endosperm of P. decomposita on germination, seedling growth and amylases activities of wheat seeds were examined in this paper. The results showed that the seed, especially the endosperm tissue of P. decomposita contained substances that strongly suppressed seed germination. The crude extract of endosperm of P. decomposita, which significantly reduced the activities of ? and ?-amylase, showed a more significant inhibition than that of seed coat at the same dose. It was concluded that the presence of inhibitory substances in seed, especially in endosperm tissue, seem to be responsible for P. decomposita seed dormancy. PMID:22963917

  16. GERMINATION OF SEEDS OF BIG AND BOTTLEBRUSH SQUIRRELTAIL

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey] and big squirreltail [E. multisetus (J. G. Smith) Burtt Davy) are short lived perennial bunchgrasses found on rangelands from the Pacific Coast to the Great Plains and from Canada to Mexico. They are valuable native species seeded to suppress...

  17. Arabinan Metabolism during Seed Development and Germination in Arabidopsis

    Microsoft Academic Search

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

    2009-01-01

    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

  18. Seed germination of Calendula officinalis 'Carola' in response to temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calendula (Calendula officinalis 'Carola') is a potential agronomic oilseed crop with application in the paint, coating, and cosmetic industry. Calendula has historically been used for herbal medicinal purposes and an ornamental plant. With the discovery that calendula seeds contain high concentrati...

  19. Thlaspi arvense (Pennycress) germination, bolting and mechanical harvest seed loss

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pennycress is being developed as an off-season rotation crop between annual corn and soybean production. This rotation scheme may offer distinct advantages to farmers by providing additional farm income from an otherwise fallow season with little impact on the subsequent soybean production. The seed...

  20. Seed germination of calendula in response to temperature

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Calendula (Calendula officinalis L.) has been used historically for herbal medicinal purposes and as an ornamental plant. With the discovery that calendula seeds contain high concentrations of calendic acid (C18:3) in the 1980s it began to be investigated as an oilseed crop for use in paint, coating...

  1. Changes in stability of isocitrate dehydrogenase (NADP+) during germination of castor bean seeds.

    PubMed

    Satoh, Y

    1980-07-01

    In crude extract of castor bean endosperm, isocitrate dehydrogenase (NADP+) (EC 1.1.1.42) was stable at 57 degrees C at the beginning of seed germination as well as in maturing and dry seeds. The enzyme gradually became less thermostable as germination proceeded and became unstable after 4 days. Extract from 5-day-old endosperm reduced the thermostability of the thermostable enzyme. The destabilizing factor accumulated in the endosperm as germination progressed and was identified as ricinoleate. Ricinoleate destabilized the purified enzyme which was stabilized by isocitrate and Mg2+, but ricinoleate did not affect the activity of NADP+-isocitrate dehydrogenase itself. Stearate, oleate, palmitate and myristate were similar to ricinoleate in their effect on the thermostability of the enzyme. The thermolabile enzyme in the crude extract of 5-day-old endosperm was readily inactivated by trypsin and in low concentrations of buffer. The thermostable enzyme in the crude extract of 2-day-old endosperm was not affected by these treatments. The thermostable enzyme treated with ricinoleate showed the same instabilities as the thermolabile enzyme. The role of ricinoleate in the germinating castor bean endosperm is discussed. PMID:7397230

  2. Temperature and water stress during conditioning and incubation phase affecting Orobanche crenata seed germination and radicle growth

    PubMed Central

    Moral, Juan; Lozano-Baena, María Dolores; Rubiales, Diego

    2015-01-01

    Orobanche crenata is a holoparasitic plant that is potentially devastating to crop yield of legume species. Soil temperature and humidity are known to affect seed germination, however, the extent of their influence on germination and radicle growth of those of O. crenata is largely unknown. In this work, we studied the effects of temperature, water potential (?t) and the type of water stress (matric or osmotic) on O. crenata seeds during conditioning and incubation periods. We found that seeds germinated between 5 and 30°C during both periods, with a maximum around 20°C. Germination increased with increasing ?t from ?1.2 to 0 MPa during conditioning and incubation periods. Likewise, seed germination increased logarithmically with length of conditioning period until 40 days. The impact of the type of water stress on seed germination was similar, although the radicle growth of seeds under osmotic stress was lower than under matric stress, what could explain the lowest infestation of Orobanche sp. in regions characterized by saline soil. The data in this study will be useful to forecast infection of host roots by O. crenata.

  3. Temperature and water stress during conditioning and incubation phase affecting Orobanche crenata seed germination and radicle growth.

    PubMed

    Moral, Juan; Lozano-Baena, María Dolores; Rubiales, Diego

    2015-01-01

    Orobanche crenata is a holoparasitic plant that is potentially devastating to crop yield of legume species. Soil temperature and humidity are known to affect seed germination, however, the extent of their influence on germination and radicle growth of those of O. crenata is largely unknown. In this work, we studied the effects of temperature, water potential (?t) and the type of water stress (matric or osmotic) on O. crenata seeds during conditioning and incubation periods. We found that seeds germinated between 5 and 30°C during both periods, with a maximum around 20°C. Germination increased with increasing ?t from -1.2 to 0 MPa during conditioning and incubation periods. Likewise, seed germination increased logarithmically with length of conditioning period until 40 days. The impact of the type of water stress on seed germination was similar, although the radicle growth of seeds under osmotic stress was lower than under matric stress, what could explain the lowest infestation of Orobanche sp. in regions characterized by saline soil. The data in this study will be useful to forecast infection of host roots by O. crenata. PMID:26089829

  4. Effect of cadmium on resumption of respiration in cotyledons of germinating pea seeds

    Microsoft Academic Search

    Moêz Smiri; Abdelilah Chaoui; Nicolas Rouhier; Eric Gelhaye; Jean-Pierre Jacquot; Ezzedine El Ferjani

    2010-01-01

    Pea seeds (Pisum sativum L.) were germinated by soaking in H2O or 5mM CdCl2 during a 5-day period. Enzyme activities involved in respiratory metabolism were studied in cotyledons. Mitochondrial cytochrome c oxidase and NADH- and succinate-cytochrome c reductase activities were inhibited by cadmium treatment. The effects of Cd were performed in vivo and in vitro allowing to distinguish between the

  5. Developmental regulation in cotton seed germination: polyadenylation of stored messenger RNA

    Microsoft Academic Search

    Barry Harris; Leon Dure

    1978-01-01

    Evidence that RNA preexisting in the cotyledons of mature cotton seed (stored mRNA) is polyadenylated during the first day of germination is presented, based on three different experimental data sets. First, actinomycin D is found to inhibit ³²POâ incorporation into mRNA-poly(A) by 62%, into mRNA by 70%, but into poly(A) only 30%. Second, far more ³²POâ and (2-³H)adenosine are incorporated

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

    Microsoft Academic Search

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

    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

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

    Microsoft Academic Search

    Li Quanhong; Fu Caili

    2005-01-01

    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

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

    Microsoft Academic Search

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

    2011-01-01

    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

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

    Microsoft Academic Search

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

    2012-01-01

    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

  10. Overexpression of FAD2 promotes seed germination and hypocotyl elongation in Brassica napus

    Microsoft Academic Search

    Maohua Wang; Mianxue Liu; Dekuan Li; Jun Wu; Xufeng Li; Yi Yang

    2010-01-01

    The enzyme fatty acid desaturase 2 (FAD2) transforms oleic acid (C18:1) to linoleic acid (C18:2) in plants and as such is\\u000a involved in fatty acid synthesis. It is also involved in plant development and self-defense, such as seed germination, leaf\\u000a expansion and cold resistance. We have cloned the full coding region of the Brassica napus\\u000a FAD2 gene and ectopically expressed

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

    PubMed

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

    2014-04-01

    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

  12. Development of an Automated Seed Sowing and Induced Germination System for Space Flight Application

    NASA Technical Reports Server (NTRS)

    Heyenga, A. G.; Kliss, Mark

    1995-01-01

    The successful utilization of higher plants in space flight is likely to require the effective transition of plants through all phases of growth and development. A particularly sensitive and critical stage in this cycle is seed germination. The present inflight capability to manipulate seed from a state of dormancy to germination and the performance of such activity under aseptic conditions is extremely limited. An Automated Sowing Mechanism (ASM) has been designed to address this area of science and technology. The self-contained system is readily compatible with the existing Shuttle middeck locker Plant Growth Unit (PGU) and planned Plant Growth Facility (PGF), presenting an opportunity to extend the experimental capability of these systems. The ASM design encompasses the controlled transition of seed from a dry to hydrated state utilizing solid media substrate as the source of water and nutrient support. System activation has been achieved with both photo and timing mechanisms. Controlled induced germination and development of various plant species has been achieved in ground-based trials. The system is presently being prepared for a KC-135 flight test.

  13. Seed germination and life history syndromes in the California chaparral

    Microsoft Academic Search

    Jon E. Keeley

    1991-01-01

    Syndromes are life history responses that are correlated to environmental regimes and are shared by a group of species (Stebbins,\\u000a 1974). In the California chaparral there are two syndromes contrasted by the timing of seedling recruitment relative to wildfires.\\u000a One syndrome, here called the fire-recruiter or refractory seed syndrome, includes species (both resprouting and non-resprouting)\\u000a which share the feature that

  14. LIQUID NITROGEN CONTROLS SEED-BORNE CHALCIDS WITHOUT REDUCING GERMINATION IN CORIANDER SEEDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Coriander (Coriandrum sativum) seeds are susceptible to infestation by chalcid (Systole) wasps which often render the seeds inviable. Control of chalcids in seeds is a prerequisite for supplying coriander germplasm to requestors throughout the world. Levels of chalcid infestation in coriander seed...

  15. Isozymes of peroxidase induced by cold stratification and hydrogen peroxide during seed germination of loblolly pine (Pinus taeda L.) 

    E-print Network

    Lee, Yung-Sheng

    1994-01-01

    is toxic to most seeds, but exposure to low concentrations of HP prior to germination increases the germination rate in Pinus taeda L. As part of a larger study of the characterization of the peroxidase in loblolly pine (LP), there were two objectives... and are induced by various chemical and stress treatments. In this thesis I address how IPODs were induced by HP and cold strati6cation during seed germination of P. taeda L. CHAPTER H OBJECTIVES As part of a larger study of the characterization...

  16. Effects of light, temperature and seed age on the germination of the winter annuals Veronica arvensis L. and Myosotis ramosissima Rochel ex. Schult

    Microsoft Academic Search

    J. G. M. Janssen

    1973-01-01

    Germination assays are performed on seeds of the winter annuals Veronica arvensis L. and Myosotis ramosissima Rochel ex Schult. after various periods of storage of the seeds, at different temperatures and in constant darkness as well as under a daily light regime. The differences in germination characteristics between the two annuals as related to light, temperature and seed age are

  17. Effects of moist cold stratification on germination, plant growth regulators, metabolites and embryo ultrastructure in seeds of Acer morrisonense (Sapindaceae).

    PubMed

    Chen, Shun-Ying; Chou, Shih-Han; Tsai, Ching-Chu; Hsu, Wen-Yu; Baskin, Carol C; Baskin, Jerry M; Chien, Ching-Te; Kuo-Huang, Ling-Long

    2015-09-01

    Breaking of seed dormancy by moist cold stratification involves complex interactions in cells. To assess the effect of moist cold stratification on dormancy break in seeds of Acer morrisonense, we monitored percentages and rates of germination and changes in plant growth regulators, sugars, amino acids and embryo ultrastructure after various periods of cold stratification. Fresh seeds incubated at 25/15 °C for 24 weeks germinated to 61%, while those cold stratified at 5 °C for 12 weeks germinated to 87% in 1 week. Neither exogenous GA3 nor GA4 pretreatment significantly increased final seed germination percentage. Total ABA content of seeds cold stratified for 12 weeks was reduced about 3.3-fold, to a concentration similar to that in germinated seeds (radicle emergence). Endogenous GA3 and GA7 were detected in 8-week and 12-week cold stratified seeds but not in fresh seeds. Numerous protein and lipid bodies were present in the plumule, first true leaves and cotyledons of fresh seeds. Protein and lipid bodies decreased greatly during cold stratification, and concentrations of total soluble sugars and amino acids increased. The major non-polar sugars in fresh seeds were sucrose and fructose, but sucrose increased and fructose decreased significantly during cold stratification. The major free amino acids were proline and tryptophan in fresh seeds, and proline increased and tryptophan decreased during cold stratification. Thus, as dormancy break occurs during cold stratification seeds of A. morrisonense undergo changes in plant growth regulators, proteins, lipids, sugars, amino acids and cell ultrastructure. PMID:26094157

  18. Seed storage oil mobilization is important but not essential for germination or seedling establishment in Arabidopsis.

    PubMed

    Kelly, Amélie A; Quettier, Anne-Laure; Shaw, Eve; Eastmond, Peter J

    2011-10-01

    Triacylglycerol (TAG) is a major storage reserve in many plant seeds. We previously identified a TAG lipase mutant called sugar-dependent1 (sdp1) that is impaired in TAG hydrolysis following Arabidopsis (Arabidopsis thaliana) seed germination (Eastmond, 2006). The aim of this study was to identify additional lipases that account for the residual TAG hydrolysis observed in sdp1. Mutants were isolated in three candidate genes (SDP1-LIKE [SDP1L], ADIPOSE TRIGLYCERIDE LIPASE-LIKE, and COMPARATIVE GENE IDENTIFIER-58-LIKE). Analysis of double, triple, and quadruple mutants showed that SDP1L is responsible for virtually all of the residual TAG hydrolysis present in sdp1 seedlings. Oil body membranes purified from sdp1 sdp1L seedlings were deficient in TAG lipase activity but could still hydrolyze di- and monoacylglycerol. SDP1L is expressed less strongly than SDP1 in seedlings. However, SDP1L could partially rescue TAG breakdown in sdp1 seedlings when expressed under the control of the SDP1 or 35S promoters and in vitro assays showed that both SDP1 and SDP1L can hydrolyze TAG, in preference to diacylglycerol or monoacylglycerol. Seed germination was slowed in sdp1 sdp1L and postgerminative seedling growth was severely retarded. The frequency of seedling establishment was also reduced, but sdp1 sdp1L was not seedling lethal under normal laboratory growth conditions. Our data show that together SDP1 and SDP1L account for at least 95% of the rate of TAG hydrolysis in Arabidopsis seeds, and that this hydrolysis is important but not essential for seed germination or seedling establishment. PMID:21825108

  19. [Effects of light quality on the seed germination of main tree species in a secondary forest ecosystem of Northeast China].

    PubMed

    Zhang, Min; Zhu, Jiao-Jun; Yan, Qiao-Ling

    2012-10-01

    This paper explored the effects of light quality on the seed germination of five dominant tree species (Larix kaempferi, Phellodendron amurense, Acer mono, Fraxinus mandshurica, and Pinus koraiensis) in a secondary forest ecosystem of Northeast China, based on the experiments with the seeds of the five tree species in laboratory and those of the P. koraiensis and L. kaempferi in the field. Four treatments of different light quality were designed in laboratory (taking dark as the control), and three treatments of R/FR (the ratio of red light and far red light intensity) were installed in the field. The laboratory experiment showed that light quality had less effect on the seed germination of L. kaempferi, but the seed germination rates of the other four tree species were significantly different under the treatments of different light quality. P. amurense had the highest seed germination rate under white light, whereas A. mono, F. mandshurica, and P. koraiensis had the highest one under the alternative irradiation with red light and far red light (R-FR-R). In consistence with the results in laboratory, the seed germination rate of P. koraiensis in the field decreased with decreasing R/FR ratio, while that of L. kaempferi was less affected. Under natural condition, the R-FR-R fluctuated with the activity of sun-fleck, and the seed germination patterns of A. mono, F. mandshurica, and P. koraiensis could be the adaptation to the sun-fleck environment in forest stand. The germination of large seeds was significantly affected by light quality. PMID:23359919

  20. Accumulation of long-lived mRNAs associated with germination in embryos during seed development of rice

    PubMed Central

    Sano, Naoto; Ono, Hanako; Murata, Kazumasa; Yamada, Tetsuya; Hirasawa, Tadashi; Kanekatsu, Motoki

    2015-01-01

    Mature dry seeds contain translatable mRNAs called long-lived mRNAs. Early studies have shown that protein synthesis during the initial phase of seed germination occurs from long-lived mRNAs, without de novo transcription. However, the gene expression systems that generate long-lived mRNAs in seeds are not well understood. To examine the accumulation of long-lived mRNAs in developing rice embryos, germination tests using the transcriptional inhibitor actinomycin D (Act D) were performed with the Japonica rice cultivar Nipponbare. Although over 70% of embryos at 10 days after flowering (DAF) germinated in the absence of the inhibitor, germination was remarkably impaired in embryos treated with Act D. In contrast, more than 70% of embryos at 20, 25, 30 and 40 DAF germinated in the presence of Act D. The same results were obtained when another cultivar, Koshihikari, was used, indicating that the long-lived mRNAs required for germination predominantly accumulate in embryos between 10 and 20 DAF during seed development. RNA-Seq identified 529 long-lived mRNA candidates, encoding proteins such as ABA, calcium ion and phospholipid signalling-related proteins, and HSP DNA J, increased from 10 to 20 DAF and were highly abundant in 40 DAF embryos of Nipponbare and Koshihikari. We also revealed that these long-lived mRNA candidates are clearly up-regulated in 10 DAF germinating embryos after imbibition, suggesting that the accumulation of these mRNAs in embryos is indispensable for the induction of germination. The findings presented here may facilitate in overcoming irregular seed germination or producing more vigorous seedlings. PMID:25941326

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

    PubMed Central

    Kesari, Vigya; Rangan, Latha

    2011-01-01

    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

  2. Radiation processing for elimination of Salmonella typhimurium from inoculated seeds used for sprout making in India and effect of irradiation on germination of seeds.

    PubMed

    Saroj, Sunil D; Hajare, Sachin; Shashidhar, R; Dhokane, Varsha; Sharma, Arun; Bandekar, Jayant R

    2007-08-01

    The effect of radiation processing on the germination of the sprout seeds mung (Phaseolus aureus), matki (Phaseolus aconitifolius), chana (Cicer arietinum), and vatana (Pisum sativum) in terms of percent germination, germination yield, sprout length, vitamin C content, and texture was investigated. Gradual decreases in the percent germination, germination yield, and sprout length with increases in radiation dose (0.5 to 2.0 kGy) were observed. Vitamin C content and texture remained unaffected for the seeds treated with doses of up to 2 kGy. To determine the efficacy of radiation treatment in elimination of foodborne pathogens, seeds inoculated with 4 log CFU/g of Salmonella Typhimurium were treated with radiation doses of 1 and 2 kGy. A reduction in counts of Salmonella Typhimurium in inoculated seeds after radiation treatment was observed. A radiation dose of 2 kGy resulted in the complete elimination of 4 log CFU/g of Salmonella Typhimurium from the inoculated seeds. However, on sprouting for 48 h, the count of Salmonella Typhimurium reached 8 log CFU/g for the control seeds and the seeds treated with a 1-kGy radiation dose. The aerobic plate counts for seeds were 2.0 to 2.6 log CFU/g, which were reduced to 0.9 to 1.2 log CFU/g on treatment with a 2-kGy radiation dose. On sprouting for 48 h, the aerobic plate count reached 8 log CFU/g for both the control and radiation-treated seeds. The study demonstrates that irradiation can control bacterial levels on seeds but not contamination introduced during posttreatment handling. Therefore, radiation processing of the final product (sprouts) is recommended, rather than of the seeds. PMID:17803158

  3. Dormancy and Germination In Vitro Response of Hydrangea Macrophylla and Hydrangea paniculata Seed to Light, Stratification, and Gibberellic Acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seed germination was optimized for ten Hydrangea macrophylla cultivars and two Hydrangea paniculata cultivars in vitro. Methods were also developed to assay seed physiology. Best results were obtained with 0.5X Gamborgs solid media in conjunction with Plant Preservative Mixture (PPM), and by sterili...

  4. POPULATION AND ENVIRONMENTAL EFFECTS ON SEED PRODUCTION, GERMINATION, AND SEEDLING VIGOR IN WESTERN WHEATGRASS (PASCOPYRUM SMITHII [RYDB.] A. LOVE)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Western wheatgrass (Pascopyrum smithii [Rydb.] A. Love) has low seed production and poor germination and seedling vigor, limiting its use when quick establishment is needed to stabilize degraded rangelands. This study examined differences among germplasm sources and determined effects of seed produ...

  5. Application of a Computer-Aided Image Analysis System to Evaluate Seed Germination under Different Environmental Conditions

    Microsoft Academic Search

    A. DELL' AQUILA

    BACKGROUND. Computer-aided image analysis tech- niques have been recently developed in monitoring seed imbibition. Their integration with the standard germination test is needed to describe the germina- tion performance of a seed sample with high accura- cy. METHODS. The image analysis system consists of two sets of components: a), an environmental system, which includes a thermostatic cell, a timer controlled

  6. Phenolic profile and antioxidant activity in selected seeds and sprouts.

    PubMed

    Paj?k, Paulina; Socha, Robert; Ga?kowska, Dorota; Ro?nowski, Jacek; Fortuna, Teresa

    2014-01-15

    The aim of this study was to investigate the effect of germination on the phenolic acids and flavonoids profile, as well as antioxidant activity (AA), in selected edible seeds of mung beans, radish, broccoli and sunflower. Germination increased the total phenolic (TP) and flavonoid (TF) levels, as well as the AA of the seeds, and influenced the profile of free and bound phenolic compounds. Among the samples, mung bean was characterised by lowest levels of TP and TF, as well as AA, evaluated using ABTS, DPPH and FRAP assays. Sunflower and radish sprouts were the most rich in phenolic compounds. Insignificant amounts of free phenolic acids were found in the free phenolic acid fraction; alkaline hydrolysis of the seeds and sprouts extracts provided the majority of the phenolic acids. The amounts of free and bound flavonoids were inconsiderable both for seeds and sprouts. PMID:24054243

  7. Superoxide and its metabolism during germination and axis growth of Vigna radiata (L.) Wilczek seeds

    PubMed Central

    Singh, Khangembam Lenin; Chaudhuri, Abira; Kar, Rup Kumar

    2014-01-01

    Involvement of reactive oxygen species in regulation of plant growth and development is recently being demonstrated with various results depending on the experimental system and plant species. Role of superoxide and its metabolism in germination and axis growth was investigated in case of Vigna radiata seeds, a non-endospermous leguminous species having epigeal germination, by studying the effect of different reactive oxygen species (ROS) inhibitors, distribution of O2•? and H2O2 and ROS enzyme profile in axes. Germination percentage and axis growth were determined under treatment with ROS inhibitors and scavengers. Localization of O2•? and H2O2 was done using nitroblue tetrazolium (NBT) and 3,3?,5,5?-tetramethyl benzidine dihydrochloride hydrate (TMB), respectively. Apoplastic level of O2•? was monitored by spectrophotometric analysis of bathing medium of axes. Profiles of NADPH oxidase and superoxide dismutase (SOD) were studied by in-gel assay. Germination was retarded by treatments affecting ROS level except H2O2 scavengers, while axis growth was retarded by all. Superoxide synthesis inhibitor and scavenger prevented H2O2 accumulation in axes in later phase as revealed from TMB staining. Activity of Cu/Zn SOD1 was initially high and declined thereafter. Superoxide being produced in apoplast possibly by NADPH oxidase activity is further metabolized to •OH via H2O2. Germination process depends possibly on •OH production in the axes. Post-germinative axis growth requires O2•? while the differentiating zone of axis (radicle) requires H2O2 for cell wall stiffening. PMID:25763616

  8. Temperature controls seed germination and dormancy in the European woodland herbaceous perennial Erythronium dens-canis (Liliaceae).

    PubMed

    Mondoni, A; Rossi, G; Probert, R

    2012-05-01

    We examined the germination ecology and the temperature requirements for germination of Erythronium dens-canis, under both outdoor and laboratory conditions. E. dens-canis is a spring flowering woodland geophyte widely distributed across Europe. Germination phenology, including embryo development and radicle and cotyledon emergence, were investigated in a natural population growing in Northern Italy. Immediately after harvest, seeds of E. dens-canis were either sown on agar in the laboratory under simulated seasonal temperatures or placed in nylon mesh sachets and buried in the wild. Embryos, undifferentiated at the time of seed dispersal, grew during summer and autumn conditions in the laboratory and in the wild, culminating in radicle emergence in winter when temperatures fell to ? 5 °C. Emergence of cotyledons did not occur immediately after radicle emergence, but was delayed until the end of winter. Laboratory experiments showed that temperature is the main factor controlling dormancy and germination, with seeds becoming non-dormant only when given warmth, followed by cold stratification. Unlike seeds of E. dens-canis that germinate in winter, in other Erythronium species radicle emergence occurs in autumn, while in some it is delayed until seeds are transferred from winter to spring conditions. Our results suggest that there is genetic and environmental control of the expression of seed dormancy amongst Erythronium species, which is related to local climate. PMID:22117612

  9. Short seed longevity, variable germination conditions, and infrequent establishment events provide a narrow window for Yucca brevifolia (Agavaceae) recruitment

    USGS Publications Warehouse

    Bryant, M.; Reynolds, J.; DeFalco, Lesley A.; Esque, Todd C.

    2012-01-01

    PREMISE OF THE STUDY: The future of long-lived stand-forming desert plants such as Yucca brevifolia (Joshua tree) has come into question in light of climate variation and landscape-scale disturbances such as wildfire. Understanding plant establishment dynamics is important for mitigating the impacts of disturbances and promoting revegetation. • METHODS: We placed Y. brevifolia seeds in shallow caches and manipulated granivore access, nurse shrub effects, and the season of cache placement to determine conditions for seed germination and seedling establishment. • KEY RESULTS: Greatest seedling emergence occurred during spring and summer, when increased soil moisture was accompanied by warm soil temperatures. Late winter-spring emergence for cached seeds was enhanced beneath shrub canopies, but seedling survival declined beneath shrubs as temperatures increased in spring. Germinability of seed remaining in the soil was reduced from 50-68% after 12 mo residence time in soil and declined to <3% after 40 mo. Following dispersal from parent plants, seeds are either removed by granivores or lose germinability, imposing substantial losses of potential germinants. • CONCLUSIONS: Specific germination and establishment requirements impose stringent limits on recruitment rates for Y. brevifolia. Coupled with infrequent seed availability, the return rates to prefire densities and demographic structure may require decades to centuries, especially in light of potential changes to regional desert climate in combination with the potential for fire recurrence. Demographic patterns are predicted to vary spatially in response to environmental variability that limits recruitment and may already be apparent among extant populations.

  10. Seed Dormancy and Germination of the European Chaerophyllum temulum (Apiaceae), a Member of a Trans-Atlantic Genus

    PubMed Central

    Vandelook, Filip; Bolle, Nele; Van Assche, Jozef A.

    2007-01-01

    Background and Aims The European Chaerophyllum temulum and two North American Chaerophyllum species have a trans-Atlantic disjunct distribution. This work aimed to resolve requirements for dormancy break and germination of C. temulum seeds and to compare dormancy traits with those of the two North American congeners. Methods Phenology of germination and embryo growth was studied by regularly exhuming seeds sown in natural conditions. Temperature requirements for embryo growth, breaking of dormancy and germination were determined by incubating seeds under controlled laboratory conditions. Additionally the effect of GA3 on germination was tested to determine the specific dormancy type. Key Results In natural conditions, embryo growth starts in early winter. Seedlings emerge in late winter shortly after the embryos reached the critical ratio for embryo length to seed length (E : S) of approx. 0·95. Growth of the embryo only occurs during a prolonged incubation period at 5 °C. After stratification at 5 °C, which breaks physiological and morphological dormancy, seeds can germinate at a wide range of temperatures. GA3 did not substitute for cold stratification in seeds placed at 23 °C. Conclusions Chaerophyllum temulum has deep complex morphophysiological dormancy. This dormancy type differs considerably from that of the two North American congeners. PMID:17556382

  11. The Arabidopsis MYB96 Transcription Factor Is a Positive Regulator of ABSCISIC ACID-INSENSITIVE4 in the Control of Seed Germination.

    PubMed

    Lee, Kyounghee; Lee, Hong Gil; Yoon, Seongmun; Kim, Hyun Uk; Seo, Pil Joon

    2015-06-01

    Seed germination is a key developmental transition that initiates the plant life cycle. The timing of germination is determined by the coordinated action of two phytohormones, gibberellin and abscisic acid (ABA). In particular, ABA plays a key role in integrating environmental information and inhibiting the germination process. The utilization of embryonic lipid reserves contributes to seed germination by acting as an energy source, and ABA suppresses lipid degradation to modulate the germination process. Here, we report that the ABA-responsive R2R3-type MYB transcription factor MYB96, which is highly expressed in embryo, regulates seed germination by controlling the expression of ABSCISIC ACID-INSENSITIVE4 (ABI4) in Arabidopsis (Arabidopsis thaliana). In the presence of ABA, germination was accelerated in MYB96-deficient myb96-1 seeds, whereas the process was significantly delayed in MYB96-overexpressing activation-tagging myb96-ox seeds. Consistently, myb96-1 seeds degraded a larger extent of lipid reserves even in the presence of ABA, while reduced lipid mobilization was observed in myb96-ox seeds. MYB96 directly regulates ABI4, which acts as a repressor of lipid breakdown, to define its spatial and temporal expression. Genetic analysis further demonstrated that ABI4 is epistatic to MYB96 in the control of seed germination. Taken together, the MYB96-ABI4 module regulates lipid mobilization specifically in the embryo to ensure proper seed germination under suboptimal conditions. PMID:25869652

  12. Irrigation and Seed Quality Development in Rapid-cycling Brassica: Seed Germination and Longevity

    Microsoft Academic Search

    U. R. S INNIAH; R. H. E LLIS; P. J OHN

    Irrigation of rapid-cycling brassica (Brassica campestris (rapa) L.) plants either ended 16 or 24 days after pollination (DAP) or continued throughout the experiment (control). Seeds were harvested serially from these plants during their development and maturation. The earlier irrigation to the mother plant ended, the earlier mass maturity (end of seed- filling phase) occurred, the lower the final seed dry

  13. Toxic effects of nanoparticles on bioluminescence activity, seed germination, and gene mutation.

    PubMed

    Ko, Kyung-Seok; Kong, In Chul

    2014-04-01

    The potential environmental toxicities of several metal oxide nanoparticles (NPs; CuO, TiO2, NiO, Fe2O3, ZnO, and Co3O4) were evaluated in the context of bioluminescence activity, seed germination, and bacterial gene mutation. The bioassays exhibited different sensitivities, i.e., each kind of NP exhibited a different level of toxicity in each of the bioassays. However, with a few exceptions, CuO and ZnO NPs had most toxic for germination of Lactuca seed (EC50 0.46 mg CuO/l) and bioluminescence (EC50 1.05 mg ZnO/l). Three NPs (Co3O4, TiO2, and Fe2O3) among all tested concentrations (max. 1,000 mg/l) showed no inhibitory effects on the tested organisms, except for Co3O4 NPs on bioluminescence activity (EC50 62.04 mg/l). The sensitivity of Lactuca seeds was greater than that of Raphanus seeds (EC50 0.46 mg CuO/l versus 26.84 mg CuO /l ). The ranking of metal toxicity levels on bioluminescence was in the order of ZnO?>?CuO?>?Co3O4?>?NiO?>?Fe2O3, TiO2, while CuO?>?ZnO?>?NiO?>?Co3O4, Fe2O3, TiO2 on germination. No revertant mutagenic ratio (greater than 2.0) of Salmonella typhimurium TA 98 was observed under any tested condition. These findings demonstrate that several bioassays, as opposed to any single one, are needed for the accurate assessment of NP toxicity on ecosystems. PMID:24297479

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

    PubMed Central

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

    2013-01-01

    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

  15. Hoarding decisions by Edward's long-tailed rats (Leopoldamys edwardsi) and South China field mice (Apodemus draco): the responses to seed size and germination schedule in acorns.

    PubMed

    Chang, Gang; Xiao, Zhishu; Zhang, Zhibin

    2009-09-01

    Co-varying traits in acorns such as seed size and germination schedule are important to influence the behavioural decisions of hoarding rodents. Using acorn pairs from cork oak (Quercus variabilis) (large size and short germination schedules) serrate oak (Q. serrata) (small size and short germination schedule) and qinggang (Cyclobalanopsis glauca) (small size and long germination schedule) with contrasting seed size and germination schedule, we conducted a series of experiments to investigate hoarding preferences in response to seed size and germination schedule by Edward's long-tailed rats (Leopoldamys edwardsi) and South China field mice (Apodemus draco) in semi-natural enclosures. We found that the seed size hypothesis was consistently supported: both rodent species ate more small acorns but hoarded more large ones regardless of germination schedules. However, the germination schedule hypothesis was also supported when similar sized acorns were simultaneously provided, e.g. Q. serrata versus C. glauca or germinating versus non-germinating Q. variabilis. Our results, contrary to the studies from North America, indicate that seed size is more important than germination schedules in determining whether the tested animals eat or hoard a given seed. PMID:19615609

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

    PubMed Central

    Zhang, Wen-Hao

    2012-01-01

    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

  17. RECUPERATION OF THE HIGH GERMINABILITY CONDITION OF PAPAYA SEED THROUGH PRIMING TECHNOLOGY AND BIOREGULATORS RECUPERACIÓN DE LA ALTA CAPACIDAD DE GERMINACIÓN DE LA SEMILLA DE PAPAYA MEDIANTE LA TECNOLOGÍA DE PREACONDICIONAMIENTO y BIORREGULADORES

    Microsoft Academic Search

    Francisco Bautista-Calles; Guillermo Carrillo-Castañeda; Ángel Villegas-Monter

    Rapid loss of seed viability of Carica papaya L. (papaya) and its high commercial price impairs the availability of high quality seed to growers. Certified papaya seed cv. Maradol was utilized to define practical methodologies to restore the seed germination performance. Seed was submitted to: 1) hydropriming: 4 d of hydropriming rose seed germination up to 84%, 250% more than

  18. An integrated RNA-Seq and network study reveals a complex regulation process of rice embryo during seed germination.

    PubMed

    Wei, Ting; He, Zilong; Tan, XinYu; Liu, Xue; Yuan, Xiao; Luo, Yingfeng; Hu, Songnian

    2015-08-14

    Seed germination is a crucial stage for plant development and agricultural production. To investigate its complex regulation process, the RNA-Seq study of rice embryo was conducted at three time points of 0, 12 and 48 h post imbibition (HPI). Dynamic transcriptional alterations were observed, especially in the early stage (0-12 HPI). Seed related genes, especially those encoding desiccation inducible proteins and storage reserves in embryo, decreased drastically after imbibition. The expression profiles of phytohormone related genes indicated distinct roles of abscisic acid (ABA), gibberellin (GA) and brassinosteroid (BR) in germination. Moreover, network analysis revealed the importance of protein phosphorylation in phytohormone interactions. Network and gene ontology (GO) analyses suggested that transcription factors (TFs) played a regulatory role in functional transitions during germination, and the enriched TF families at 0 HPI implied a regulation of epigenetic modification in dry seeds. In addition, 35 germination-specific TF genes in embryo were identified and seven genes were verified by qRT-PCR. Besides, enriched TF binding sites (TFBSs) supported physiological changes in germination. Overall, this study expands our comprehensive knowledge of multiple regulation factors underlying rice seed germination. PMID:26116530

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

    PubMed Central

    Rajjou, Loïc; Gallardo, Karine; Debeaujon, Isabelle; Vandekerckhove, Joël; Job, Claudette; Job, Dominique

    2004-01-01

    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

  20. Spatial Distribution of Epigenetic Modifications in Brachypodium distachyon Embryos during Seed Maturation and Germination

    PubMed Central

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

    2014-01-01

    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

  1. Naringenin inhibits seed germination and seedling root growth through a salicylic acid-independent mechanism in Arabidopsis thaliana.

    PubMed

    Hernández, Iker; Munné-Bosch, Sergi

    2012-12-01

    Flavonoids fulfill an enormous range of biological functions in plants. In seeds, these compounds play several roles; for instance proanthocyanidins protect them from moisture, pathogen attacks, mechanical stress, UV radiation, etc., and flavonols have been suggested to protect the embryo from oxidative stress. The present study aimed at determining the role of flavonoids in Arabidopsis thaliana (L.) seed germination, and the involvement of salicylic acid (SA) and auxin (indole-3-acetic acid), two phytohormones with the same biosynthetic origin as flavonoids, the shikimate pathway, in such a putative role. We show that naringenin, a flavanone, strongly inhibits the germination of A. thaliana seeds in a dose-dependent and SA-independent manner. Altered auxin levels do not affect seed germination in Arabidopsis, but impaired auxin transport does, although to a minor extent. Naringenin and N-1-naphthylphthalamic acid (NPA) impair auxin transport through the same mechanisms, so the inhibition of germination by naringenin might involve impaired auxin transport among other mechanisms. From the present study it is concluded that naringenin inhibits the germination of Arabidopsis seeds in a dose-dependent and SA-independent manner, and the results also suggest that such effects are exerted, at least to some extent, through impaired auxin transport, although additional mechanisms seem to operate as well. PMID:23031844

  2. Influence of distillery effluent on germination and growth of mung bean (Vigna radiata) seeds.

    PubMed

    Kannan, A; Upreti, Raj K

    2008-05-01

    Distillery effluent or spent wash discharged as waste water contains various toxic chemicals that can contaminate water and soil and may affect the common crops if used for agricultural irrigation. Toxic nature of distillery effluent is due to the presence of high amounts of organic and inorganic chemical loads and its high-acidic pH. Experimental effects of untreated (Raw) distillery effluent, discharged from a distillery unit (based on fermentation of alcohol from sugarcane molasses), and the post-treatment effluent from the outlet of conventional anaerobic treatment plant (Treated effluent) of the distillery unit were studied in mung bean (Vigna radiata, L.R. Wilczek). Mung bean is a commonly used legume crop in India and its neighboring countries. Mung bean seeds were presoaked for 6h and 30 h, respectively, in different concentrations (5-20%, v/v) of each effluent and germination, growth characters, and seedling membrane enzymes and constituents were investigated. Results revealed that the leaching of carbohydrates and proteins (solute efflux) were much higher in case of untreated effluent and were also dependent to the presoaking time. Other germination characters including percentage of germination, speed of germination index, vigor index and length of root and embryonic axis revealed significant concentration-dependent decline in untreated effluent. Evaluation of seedlings membrane transport enzymes and structural constituents (hexose, sialic acid and phospholipids) following 6 h presoaking of seeds revealed concentration-dependent decline, which were much less in treated effluent as compared to the untreated effluent. Treated effluent up to 10% (v/v) concentration reflected low-observed adverse effect levels. PMID:17928137

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

    PubMed

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

    2013-08-01

    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

  4. Effect of cadmium on resumption of respiration in cotyledons of germinating pea seeds.

    PubMed

    Smiri, Moêz; Chaoui, Abdelilah; Rouhier, Nicolas; Gelhaye, Eric; Jacquot, Jean-Pierre; El Ferjani, Ezzedine

    2010-09-01

    Pea seeds (Pisum sativum L.) were germinated by soaking in H2O or 5 mM CdCl2 during a 5-day period. Enzyme activities involved in respiratory metabolism were studied in cotyledons. Mitochondrial cytochrome c oxidase and NADH- and succinate-cytochrome c reductase activities were inhibited by cadmium treatment. The effects of Cd were performed in vivo and in vitro allowing to distinguish between the direct inhibition of the enzyme activities and the influence on the same enzymes into the cell environment. However, Cd exposure stimulated an enzyme activity of fermentation and inhibited the capacity of the enzyme inactivator (alcohol dehydrogenase inactivator). Moreover, the enzyme activities of NAD(P)H-recycling dehydrogenases via secondary pentose phosphate pathway, glucose-6-phosphate- and 6-phosphogluconate-dehydrogenases, were enhanced in Cd-stressed seeds. These disturbances suggest that cadmium may inflict a serious injury on renewal of respiration. The findings will help clarify the overall mechanisms that underlie cadmium-mediated toxicity in germinating seeds. PMID:20570353

  5. Irrigation and Seed Quality Development in Rapid-cycling Brassica: Seed Germination and Longevity

    Microsoft Academic Search

    U. R SINNIAH; R. H ELLIS; P JOHN

    1998-01-01

    Irrigation of rapid-cycling brassica (Brassica campestris [rapa]L.) plants either ended 16 or 24 days after pollination (DAP) or continued throughout the experiment (control). Seeds were harvested serially from these plants during their development and maturation. The earlier irrigation to the mother plant ended, the earlier mass maturity (end of seed-filling phase) occurred, the lower the final seed dry weight, and

  6. Incorporating Cache Management Behavior into Seed Dispersal: The Effect of Pericarp Removal on Acorn Germination

    PubMed Central

    Yi, Xianfeng; Zhang, Mingming; Bartlow, Andrew W.; Dong, Zhong

    2014-01-01

    Selecting seeds for long-term storage is a key factor for food hoarding animals. Siberian chipmunks (Tamias sibiricus) remove the pericarp and scatter hoard sound acorns of Quercus mongolica over those that are insect-infested to maximize returns from caches. We have no knowledge of whether these chipmunks remove the pericarp from acorns of other species of oaks and if this behavior benefits seedling establishment. In this study, we tested whether Siberian chipmunks engage in this behavior with acorns of three other Chinese oak species, Q. variabilis, Q. aliena and Q. serrata var. brevipetiolata, and how the dispersal and germination of these acorns are affected. Our results show that when chipmunks were provided with sound and infested acorns of Quercus variabilis, Q. aliena and Q. serrata var. brevipetiolata, the two types were equally harvested and dispersed. This preference suggests that Siberian chipmunks are incapable of distinguishing between sound and insect-infested acorns. However, Siberian chipmunks removed the pericarp from acorns of these three oak species prior to dispersing and caching them. Consequently, significantly more sound acorns were scatter hoarded and more infested acorns were immediately consumed. Additionally, indoor germination experiments showed that pericarp removal by chipmunks promoted acorn germination while artificial removal showed no significant effect. Our results show that pericarp removal allows Siberian chipmunks to effectively discriminate against insect-infested acorns and may represent an adaptive behavior for cache management. Because of the germination patterns of pericarp-removed acorns, we argue that the foraging behavior of Siberian chipmunks could have potential impacts on the dispersal and germination of acorns from various oak species. PMID:24647670

  7. SUPPRESSOR OF MORE AXILLARY GROWTH2 1 controls seed germination and seedling development in Arabidopsis.

    PubMed

    Stanga, John P; Smith, Steven M; Briggs, Winslow R; Nelson, David C

    2013-09-01

    Abiotic chemical signals discovered in smoke that are known as karrikins (KARs) and the endogenous hormone strigolactone (SL) control plant growth through a shared MORE AXILLARY GROWTH2 (MAX2)-dependent pathway. A SL biosynthetic pathway and candidate KAR/SL receptors have been characterized, but signaling downstream of MAX2 is poorly defined. A screen for genetic suppressors of the enhanced seed dormancy phenotype of max2 in Arabidopsis (Arabidopsis thaliana) led to identification of a suppressor of max2 1 (smax1) mutant. smax1 restores the seed germination and seedling photomorphogenesis phenotypes of max2 but does not affect the lateral root formation, axillary shoot growth, or senescence phenotypes of max2. Expression of three transcriptional markers of KAR/SL signaling, D14-LIKE2, KAR-UP F-BOX1, and INDOLE-3-ACETIC ACID INDUCIBLE1, is rescued in smax1 max2 seedlings. SMAX1 is a member of an eight-gene family in Arabidopsis that has weak similarity to HEAT SHOCK PROTEIN 101, which encodes a caseinolytic peptidase B chaperonin required for thermotolerance. SMAX1 and the SMAX1-like (SMXL) homologs are differentially expressed in Arabidopsis tissues. SMAX1 transcripts are most abundant in dry seed, consistent with its function in seed germination control. Several SMXL genes are up-regulated in seedlings treated with the synthetic SL GR24. SMAX1 and SMXL2 transcripts are reduced in max2 seedlings, which could indicate negative feedback regulation by KAR/SL signaling. smax1 seed and seedling growth mimics the wild type treated with KAR/SL, but smax1 seedlings are still responsive to 2H-furo[2,3-c]pyran-2-one (KAR2) or GR24. We conclude that SMAX1 is an important component of KAR/SL signaling during seed germination and seedling growth but is not necessary for all MAX2-dependent responses. We hypothesize that one or more SMXL proteins may also act downstream of MAX2 to control the diverse developmental responses to KARs and SLs. PMID:23893171

  8. Melatonin promotes seed germination under high salinity by regulating antioxidant systems, ABA and GA? interaction in cucumber (Cucumis sativus L.).

    PubMed

    Zhang, Hai-Jun; Zhang, Na; Yang, Rong-Chao; Wang, Li; Sun, Qian-Qian; Li, Dian-Bo; Cao, Yun-Yun; Weeda, Sarah; Zhao, Bing; Ren, Shuxin; Guo, Yang-Dong

    2014-10-01

    Although previous studies have found that melatonin can promote seed germination, the mechanisms involved in perceiving and signaling melatonin remain poorly understood. In this study, it was found that melatonin was synthesized during cucumber seed germination with a peak in melatonin levels occurring 14 hr into germination. This is indicative of a correlation between melatonin synthesis and seed germination. Meanwhile, seeds pretreated with exogenous melatonin (1 ?M) showed enhanced germination rates under 150 mM NaCl stress compared to water-pretreated seeds under salinity stress. There are two apparent mechanisms by which melatonin alleviated salinity-induced inhibition of seed germination. Exogenous melatonin decreased oxidative damage induced by NaCl stress by enhancing gene expression of antioxidants. Under NaCl stress, compared to untreated control, the activities of antioxidant enzymes including superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) were significantly increased by approximately 1.3-5.0-fold, with a concomitant 1.4-2.0-fold increase of CsCu-ZnSOD, CsFe-ZnSOD, CsCAT, and CsPOD in melatonin-pretreated seeds. Melatonin also alleviated salinity stress by affecting abscisic acid (ABA) and gibberellin acid (GA) biosynthesis and catabolism during seed germination. Compared to NaCl treatment, melatonin significantly up-regulated ABA catabolism genes (e.g., CsCYP707A1 and CsCYP707A2, 3.5 and 105-fold higher than NaCl treatment at 16 hr, respectively) and down-regulated ABA biosynthesis genes (e.g., CsNECD2, 0.29-fold of CK2 at 16 hr), resulting in a rapid decrease of ABA content during the early stage of germination. At the same time, melatonin positively up-regulated GA biosynthesis genes (e.g., GA20ox and GA3ox, 2.3 and 3.9-fold higher than NaCl treatment at 0 and 12 hr, respectively), contributing to a significant increase of GA (especially GA4) content. In this study, we provide new evidence suggesting that melatonin alleviates the inhibitory effects of NaCl stress on germination mainly by regulating the biosynthesis and catabolism of ABA and GA4. PMID:25112973

  9. Evaluation of phytotoxicity effect of olive mill wastewater treated by different technologies on seed germination of barley (Hordeum vulgare L.).

    PubMed

    Rusan, Munir J M; Albalasmeh, Ammar A; Zuraiqi, Said; Bashabsheh, Mohammad

    2015-06-01

    Olive-mill wastewater (OMW) is a by-product effluent of olive oil extraction process that is produced in large amount in the Mediterranean region. OMW is believed to induce phytotoxic effect on organisms including seed germination and plant growth. The objective of this study was to evaluate the impact of untreated and treated OMW with different techniques on seed germination of barley (Hordeum vulgare L.). The following treatments were investigated: (1) tap water (control); (2) OMW treated by aerobic biological technology in a Jacto Reactor (JR); (3) OMW treated by solar fenton oxidation (SFO); (4) OMW treated by microfiltration followed by nanofiltration (MF+NF); (5) OMW treated by microfiltration followed by reverse osmosis (MF+RO) process; (6) diluted OMW with tap water (25 % OMW); (7) diluted OMW with tap water (50 % OMW); (8) diluted OMW with tap water (75 % OMW); and (9) untreated OMW (100 % OMW). A germination test was conducted in an incubator at temperature of 23 (?)C. In each petri dish, a filter paper was mounted and ten seeds of barley were placed on the filter paper. Five milliliter of water were added to each petri dish. The seed germination was determined by counting the number of germinated seeds to calculate the percentage of germination (G %). Germination rate index (GRI), seed vigor index (SVI), and phytotoxicity index (PI) were also calculated. Then, the dry weights and lengths of the shoots and the roots of the germinated seeds were measured. The results show that 100, 75, and 50 %OMW were very phytotoxic and completely prohibited seed germination. However, phytotoxicity decreased significantly following treatments of OMW with all techniques investigated and by the 25 % OMW dilution, as results of removing the phenols and other phytotoxic organic compounds from the OMW or by diluting it. This was evidenced by relative enhancement of the dry weights and lengths of shoot and root as well as the G %, GRI, SVG, and PI. It was concluded that if OMW will be used for irrigating crops, it has to be first treated or diluted with tap water at a ratio of 1:3 OMW:water at least. The most efficient treatment techniques in reducing the phytotoxicity of OMW were the MF+RO, followed by SFO and JR. PMID:25874415

  10. Salinity Eff ects on Seed Germination and Vegetative Growth of Greens-Type Poa annua Relative to Other Cool-Season Turfgrass Species

    Microsoft Academic Search

    Jing Dai; David R. Huff; Maxim J. Schlossberg

    2009-01-01

    Seed germination and vegetative growth stud- ies were conducted to determine relative salinity tolerance of greens-type Poa annua L. com- pared with other cool-season turfgrass spe- cies. Effects of increasing salinity stress on fi nal germination percentage (FGP), germination rate (GR), clipping yield dry weight (CYD), verdure dry weight (VD), root dry weight (RD), and the longest root length (LRL)

  11. Arabidopsis Glutamate Receptor Homolog3.5 Modulates Cytosolic Ca2+ Level to Counteract Effect of Abscisic Acid in Seed Germination1[OPEN

    PubMed Central

    Kong, Dongdong; Ju, Chuanli; Parihar, Aisha; Kim, So; Cho, Daeshik; Kwak, June M.

    2015-01-01

    Seed germination is a critical step in a plant’s life cycle that allows successful propagation and is therefore strictly controlled by endogenous and environmental signals. However, the molecular mechanisms underlying germination control remain elusive. Here, we report that the Arabidopsis (Arabidopsis thaliana) glutamate receptor homolog3.5 (AtGLR3.5) is predominantly expressed in germinating seeds and increases cytosolic Ca2+ concentration that counteracts the effect of abscisic acid (ABA) to promote germination. Repression of AtGLR3.5 impairs cytosolic Ca2+ concentration elevation, significantly delays germination, and enhances ABA sensitivity in seeds, whereas overexpression of AtGLR3.5 results in earlier germination and reduced seed sensitivity to ABA. Furthermore, we show that Ca2+ suppresses the expression of ABSCISIC ACID INSENSITIVE4 (ABI4), a key transcription factor involved in ABA response in seeds, and that ABI4 plays a fundamental role in modulation of Ca2+-dependent germination. Taken together, our results provide molecular genetic evidence that AtGLR3.5-mediated Ca2+ influx stimulates seed germination by antagonizing the inhibitory effects of ABA through suppression of ABI4. These findings establish, to our knowledge, a new and pivotal role of the plant glutamate receptor homolog and Ca2+ signaling in germination control and uncover the orchestrated modulation of the AtGLR3.5-mediated Ca2+ signal and ABA signaling via ABI4 to fine-tune the crucial developmental process, germination, in Arabidopsis. PMID:25681329

  12. Arabidopsis glutamate receptor homolog3.5 modulates cytosolic Ca2+ level to counteract effect of abscisic acid in seed germination.

    PubMed

    Kong, Dongdong; Ju, Chuanli; Parihar, Aisha; Kim, So; Cho, Daeshik; Kwak, June M

    2015-04-01

    Seed germination is a critical step in a plant's life cycle that allows successful propagation and is therefore strictly controlled by endogenous and environmental signals. However, the molecular mechanisms underlying germination control remain elusive. Here, we report that the Arabidopsis (Arabidopsis thaliana) glutamate receptor homolog3.5 (AtGLR3.5) is predominantly expressed in germinating seeds and increases cytosolic Ca2+ concentration that counteracts the effect of abscisic acid (ABA) to promote germination. Repression of AtGLR3.5 impairs cytosolic Ca2+ concentration elevation, significantly delays germination, and enhances ABA sensitivity in seeds, whereas overexpression of AtGLR3.5 results in earlier germination and reduced seed sensitivity to ABA. Furthermore, we show that Ca2+ suppresses the expression of ABSCISIC ACID INSENSITIVE4 (ABI4), a key transcription factor involved in ABA response in seeds, and that ABI4 plays a fundamental role in modulation of Ca2+-dependent germination. Taken together, our results provide molecular genetic evidence that AtGLR3.5-mediated Ca2+ influx stimulates seed germination by antagonizing the inhibitory effects of ABA through suppression of ABI4. These findings establish, to our knowledge, a new and pivotal role of the plant glutamate receptor homolog and Ca2+ signaling in germination control and uncover the orchestrated modulation of the AtGLR3.5-mediated Ca2+ signal and ABA signaling via ABI4 to fine-tune the crucial developmental process, germination, in Arabidopsis. PMID:25681329

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

    Microsoft Academic Search

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

    2006-01-01

    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.

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

    PubMed

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

    2014-03-01

    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

  15. Effects of temperature, relative humidity, and scarification method on the germination of Lupinus texensis Hook. seeds 

    E-print Network

    Kaspar, Michael Joseph

    1987-01-01

    EFFECTS OF TEI'IPERA' URE, RELATIVE HUMIDI'I'Y, AND SCARIFI. ATION IV&THOD ON THE GERMINATION OI' Lf;PINUS TEXE1VSIS HOOK. SEEDS A Thesis by MICHAEL JOSEPH KASPAR Submitted to the Graduate College of' Texas Ag:M University in partial... JOSEPH KASPAR Approved as to style and content by: Edward L. cWilliams (Chairman) David Wm. Reed (Member) Dairid L. Morga (Member) David . 'ris e (Member) . Grant Vest. (Head of Department) August 1987 ABSTRACT Effects of Temperature...

  16. Raphanusanin-mediated resistance to pathogens is light dependent in radish and Arabidopsis thaliana.

    PubMed

    Moehninsi; Miura, Kenji; Yamada, Kosumi; Shigemori, Hideyuki

    2014-09-01

    Raphanusanin (Ra) is a light-induced inhibitor of hypocotyl growth that responds to unilateral blue light illumination in radish seedlings. We have previously shown that Ra regulates genes that are involved in common defense mechanisms. Many genes that are induced by Ra are also positively regulated by early blue light. To extend the understanding of the role of Ra in pathogen defense, we evaluated the effects of Ra on radish and Arabidopsis thaliana (A. thaliana) infected with the necrotrophic pathogen Botrytis cinerea (B. cinerea) and biotrophic pathogen Pseudomonas syringae (P. syringae). Radish and A. thaliana were found to be resistant to both pathogens when treated with Ra, depending on the concentration used. Interestingly, Ra-mediated resistance to P. syringae is dependent on light because Ra-treated seedlings exhibited enhanced susceptibility to P. syringae infection when grown in the dark. In addition to regulating the biotic defense response, Ra inhibited seed germination and root elongation and enhanced the growth of root hairs in the presence of light in radish and A. thaliana. Our data suggest that Ra regulates the expression of a set of genes involved in defense signaling pathways and plays a role in pathogen defense and plant development. Our results show that light may be generally required not only for the accumulation of Ra but also for its activation during the pathogen defense response. PMID:24923677

  17. Ethanol and acetaldehyde production in germinating cotton (Gossypium hirsutum L. ) seeds subjected to hypoxic stress

    SciTech Connect

    Lehle, F.R.; Ahmed, O.K.

    1987-04-01

    Alcoholic fermentation in germinating cotton seeds in response to sudden hypoxic stress was characterized. Cotton seeds were imbibed in the dark for various intervals (typically 22-24 hr) in air at 32 C and then subjected to sudden hypoxic stress by exposing seeds in light or darkness to either pure carbon dioxide or nitrogen gas in sealed vials at 28 C. EtOH and acetaldehyde (AALD) were then separated via GLC from head-space samples. Results indicated that during the first 32 hr of imbibition at 32 C, maximum EtOH forming-capacity reached a peak at 16 hr and then fell off slightly. In contrast, AALD forming-capacity during the same interval gradually increases. EtOH production as induced by CO/sub 2/ was unaffected by light conditions during incubation and average 20 nmoles x seed/sup -1/ x hr/sup -1/. EtOH production as induced by N/sub 2/ was only 55% that of CO/sub 2/ stress. AALD production as induced by CO/sub 2/ was reduced 83% under dark as compared to light incubation conditions where it averaged 2.5 nmoles x seed/sup -1/ x hr/sup -1/. EtOH and AALD levels rapidly fell following hypoxic stress relief.

  18. Control processes in the induction and relief of thermoinhibition of lettuce seed germination : actions of phytochrome and endogenous ethylene.

    PubMed

    Saini, H S; Consolacion, E D; Bassi, P K; Spencer, M S

    1989-05-01

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

  19. Characterization of water binding and germination traits of magnetically exposed maize (Zea mays L.) seeds equilibrated at different relative humidities at two temperatures.

    PubMed

    Vashisth, Ananta; Nagarajan, Shantha

    2009-04-01

    A study was undertaken to characterize the water sorption properties and enhancement in germination and seedling vigour of maize (Zea mays L.) seeds exposed to static magnetic fields of 100 mT and 200 mT for 2 and 1 h, respectively. Water sorption isotherms were constructed for magnetically- exposed and unexposed seeds by equilibrating over different saturated salt solutions at 25 and 35 degrees C. The germination and vigour parameters were evaluated for magnetically-exposed and unexposed seeds, equilibrated over the wide range of relative humidities (RHs) at 25 and 35 degrees C. Moisture content increased with increase in RH and decreased with increase in equilibrium temperature. The germination and vigour reduced at high and very low humidities. Magnetically-exposed seeds maintained higher germination and vigour at both temperatures and all RHs, indicating the better quality of magnetically-exposed seeds. The leachate conductivity of magnetically-exposed seeds was lower than unexposed seeds at all RHs, suggesting better membrane integrity in magnetically-exposed seeds. Analysis of the isotherms using D'Arcy-Watt equation revealed that irrespective of the temperature, in magnetically-treated seeds weak binding sites were more and strong and multi-molecular binding sites were less compared to the unexposed seeds. Total binding sites were more in unexposed control seeds. The modification of binding properties of seed water and increased seed membrane integrity in magnetically-exposed seeds might have enhanced the germination traits and early seedling growth of maize. PMID:19517997

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

    PubMed

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

    2012-03-01

    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

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

    PubMed Central

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

    2012-01-01

    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

  2. The biosynthesis and conjugation of indole-3-acetic acid in germinating seed and seedlings of Dalbergia dolichopetala

    Microsoft Academic Search

    A. M. Monteiro; A. Crozier; G. Sandberg

    1988-01-01

    Germinating seed ofDalbergia dolichopetala converted both [2H5]l-tryptophan and [2H5]indole-3-ethanol to [2H5]indole-3-acetic acid (IAA). Metabolism of [2'-14C]IAA resulted in the production of indole-3-acetylaspartic acid (IAAsp), as well as several unidentified components, referred to as metabolites I, II, IV and V. Re-application of [14C]IAAsp to the germinating seed led to the accumulation of the polar, water-soluble compound, metabolite V, as the major

  3. Initial changes in the transcriptome of Euphorbia esula seeds induced to germinate with a combination of constant and diurnal alternating temperatures

    Microsoft Academic Search

    Michael E. FoleyJames; James V. Anderson; Wun S. Chao; Münevver Do?ramac?; David P. Horvath

    2010-01-01

    We investigated transcriptome changes in Euphorbia esula (leafy spurge) seeds with a focus on the effect of constant and diurnal fluctuating temperature on dormancy and germination.\\u000a Leafy spurge seeds do not germinate when incubated for 21 days at 20°C constant temperatures, but nearly 30% germinate after\\u000a 21 days under fluctuating temperatures 20:30°C (16:8 h). Incubation at 20°C for 21 days followed by 20:30°C

  4. The Gibberellic Acid Signaling Repressor RGL2 Inhibits Arabidopsis Seed Germination by Stimulating Abscisic Acid Synthesis and ABI5 Activity[W

    PubMed Central

    Piskurewicz, Urszula; Jikumaru, Yusuke; Kinoshita, Natsuko; Nambara, Eiji; Kamiya, Yuji; Lopez-Molina, Luis

    2008-01-01

    Seed germination is antagonistically controlled by the phytohormones gibberellic acid (GA) and abscisic acid (ABA). GA promotes seed germination by enhancing the proteasome-mediated destruction of RGL2 (for RGA-LIKE2), a key DELLA factor repressing germination. By contrast, ABA blocks germination by inducing ABI5 (for ABA-INSENSITIVE5), a basic domain/leucine zipper transcription factor repressing germination. Decreased GA synthesis leads to an increase in endogenous ABA levels through a stabilized RGL2, a process that may involve XERICO, a RING-H2 zinc finger factor promoting ABA synthesis. In turn, increased endogenous ABA synthesis is necessary to elevate not only ABI5 RNA and protein levels but also, critically, those of RGL2. Increased ABI5 protein is ultimately responsible for preventing seed germination when GA levels are reduced. However, overexpression of ABI5 was not sufficient to repress germination, as ABI5 activity requires phosphorylation. The endogenous ABI5 phosphorylation and inhibition of germination could be recapitulated by the addition of a SnRK2 protein kinase to the ABI5 overexpression line. In sleepy1 mutant seeds, RGL2 overaccumulates; germination of these seeds can occur under conditions that produce low ABI5 expression. These data support the notion that ABI5 acts as the final common repressor of germination in response to changes in ABA and GA levels. PMID:18941053

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

    PubMed

    Yamasaki, Yoshiki; Fujimoto, Mikio; Kariya, Junji; Konno, Haruyoshi

    2005-04-01

    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

  6. Increase in ?-N-Acetylglucosaminidase Activity during Germination of Cotton Seeds 1

    PubMed Central

    Yi, Cho Kwang

    1981-01-01

    A marked increase in ?-acetylglucosaminidase (2-acetamido-2-deoxy-?-d-glucoside acetamidodeoxyglucohydrolase, EC 3.2.1.30) activity was observed in the germinating cotyledon of cotton seeds. The enzyme was isolated from cotton seedlings and purified to study its physiological function in the germination of cotton seeds. The purification procedure involves ammonium sulfate fractionation, ion-exchange chromatography, gel filtrations, and concanavalin A-Sepharose 4B chromatography, and the purified ?-N-acetylglucosaminidase was shown to be homogeneous by disc electrophoresis. The molecular weight was estimated to be about 125,000 by gel filtration. The enzyme hydrolyzed both p-nitrophenyl-N-acetyl-?-d-glucosamine and p-nitrophenyl-N-acetyl-?-d-galactosamine. When p-nitrophenyl-N-acetyl-?-d-glucosamine was used as substrate, Km and Vmax were 0.625 nanomolar and 228 moles per minute per milligram, respectively, and optimum activity was at pH 5.6. The enzyme liberated ?-linked N-acetyl-glucosamine from chitin, ovalbumin, and pronase-digested wheat germ lectin. Images PMID:16661636

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

    PubMed

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

    2013-03-01

    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

  8. HFR1 Sequesters PIF1 to Govern the Transcriptional Network Underlying Light-Initiated Seed Germination in Arabidopsis[C][W][OPEN

    PubMed Central

    Shi, Hui; Zhong, Shangwei; Mo, Xiaorong; Liu, Na; Nezames, Cynthia D.; Deng, Xing Wang

    2013-01-01

    Seed germination is the first step for seed plants to initiate a new life cycle. Light plays a predominant role in promoting seed germination, where the initial phase is mediated by photoreceptor phytochrome B (phyB). Previous studies showed that PHYTOCHROME-INTERACTING FACTOR1 (PIF1) represses seed germination downstream of phyB. Here, we identify a positive regulator of phyB-dependent seed germination, LONG HYPOCOTYL IN FAR-RED1 (HFR1). HFR1 blocks PIF1 transcriptional activity by forming a heterodimer with PIF1 that prevents PIF1 from binding to DNA. Our whole-genomic analysis shows that HFR1 and PIF1 oppositely mediate the light-regulated transcriptome in imbibed seeds. Through the HFR1–PIF1 module, light regulates expression of numerous genes involved in cell wall loosening, cell division, and hormone pathways to initiate seed germination. The functionally antagonistic HFR1–PIF1 pair constructs a fail-safe mechanism for fine-tuning seed germination during low-level illumination, ensuring a rapid response to favorable environmental changes. This study identifies the HFR1–PIF1 pair as a central module directing the whole genomic transcriptional network to rapidly initiate light-induced seed germination. PMID:24179122

  9. Effects of saline-alkaline stress on seed germination and seedling growth of Sorghum bicolor (L.) Moench.

    PubMed

    Zhao, Yanyun; Lu, Zhaohua; He, Lei

    2014-08-01

    In order to study the adaptation ability of sweet sorghum (Sorghum bicolor L. Moench) in the Yellow River Delta, the sweet sorghum variety Mart was used in this study to determine the roles of different saline-alkaline ratio stress treatment during seed germination to seedling stage. The results showed that Na+ concentration had a significant impact on the seed germination, seedling growth, and plant survival of sweet sorghum. Increasing Na+ concentration led to a decline in germination rate, final germination percentage, survival percentage, plant height, and dry weight per plant, a prolonged mean time of germination, as well as loss of improvement effect of low-Na+ concentration. The interaction effect of Na+ concentration and pH on the mean time of germination and germination rate was not significant (p<0.05). However, under the condition of low-Na+ concentration (100 mM), high pH reduced the mean time of germination and increased the germination rate, without decline in final germination percentage and survival percentage. Therefore, at least in the duration of seed germination to the harvest period in the research, the sweet sorghum was resistant to the pH stress (?9.04) when the Na+ concentration was below 100 mM. When suffered from the saline-alkaline stress, the seedling of sweet sorghum was characterized by ecological adaptive features, such as decreased stem ratio and chlorophyll b content in leaves and increased root ratio and chlorophyll a content, in order to maintain the uptakes of water and nutrient, and carbon assimilation. When the stress intensified, the lipid oxidation products, e.g., malondialdehyde (MDA), increased in sweet sorghum seedlings. However, the increasing of soluble protein content and antioxidant enzyme activity (superoxide dismutase (SOD), guaiacol peroxidase (POD), and gatalase (CAT)) was only founded in neutral low-Na+ concentration treatment (A1), which indicated that high-salt concentration and pH all elicited harmful effects and limited the self-healing ability of sweet sorghum seedlings. In all, in order to grow sweet sorghum in the saline-alkaline soils of the Yellow River Delta, the salt concentration and pH value of the soil must be taken into consideration, and seeding density should be increased and supported by appropriate irrigation measures to reduce saline-alkaline stress so as to ensure the survival and growth of sweet sorghum seedlings. PMID:24840039

  10. Involvement of reactive oxygen species in endosperm cap weakening and embryo elongation growth during lettuce seed germination

    PubMed Central

    Zhang, Yu; Chen, Bingxian; Xu, Zhenjiang; Shi, Zhaowan; Chen, Shanli; Huang, Xi; Chen, Jianxun; Wang, Xiaofeng

    2014-01-01

    Endosperm cap (CAP) weakening and embryo elongation growth are prerequisites for the completion of lettuce seed germination. Although it has been proposed that the cell wall loosening underlying these processes results from an enzymatic mechanism, it is still unclear which enzymes are involved. Here it is shown that reactive oxygen species (ROS), which are non-enzymatic factors, may be involved in the two processes. In Guasihong lettuce seeds imbibed in water, O2·– and H2O2 accumulated and peroxidase activity increased in the CAP, whereas its puncture force decreased. In addition, in the radicle, the increase in embryo growth potential was accompanied by accumulation of O2·– and an increase in peroxidase activity. Imbibing seeds in 0.3% sodium dichloroisocyanurate (SDIC) reduced endosperm viability and the levels of O2·–, H2O2, and peroxidase activity in the CAP, whereas the decrease in its puncture force was inhibited. However, in the embryo, SDIC did not affect the accumulation of O2·–, peroxidase activity, and the embryo growth potential. As a result, SDIC caused atypical germination, in which the endosperm ruptured at the boundary between the CAP and lateral endosperm. ROS scavengers and ROS generation inhibitors inhibited the CAP weakening and also decreased the embryo growth potential, thus decreasing the percentage of seed germination. Exogenous ROS and ROS generation inducers increased the percentage of CAP rupture to some extent, and the addition of H2O2 to 0.3% SDIC enabled some seeds to undergo typical germination. PMID:24744430

  11. Promotion of testa rupture during garden cress germination involves seed compartment-specific expression and activity of pectin methylesterases.

    PubMed

    Scheler, Claudia; Weitbrecht, Karin; Pearce, Simon P; Hampstead, Anthony; Büttner-Mainik, Annette; Lee, Kieran J D; Voegele, Antje; Oracz, Krystyna; Dekkers, Bas J W; Wang, Xiaofeng; Wood, Andrew T A; Bentsink, Leónie; King, John R; Knox, J Paul; Holdsworth, Michael J; Müller, Kerstin; Leubner-Metzger, Gerhard

    2015-01-01

    Pectin methylesterase (PME) controls the methylesterification status of pectins and thereby determines the biophysical properties of plant cell walls, which are important for tissue growth and weakening processes. We demonstrate here that tissue-specific and spatiotemporal alterations in cell wall pectin methylesterification occur during the germination of garden cress (Lepidium sativum). These cell wall changes are associated with characteristic expression patterns of PME genes and resultant enzyme activities in the key seed compartments CAP (micropylar endosperm) and RAD (radicle plus lower hypocotyl). Transcriptome and quantitative real-time reverse transcription-polymerase chain reaction analysis as well as PME enzyme activity measurements of separated seed compartments, including CAP and RAD, revealed distinct phases during germination. These were associated with hormonal and compartment-specific regulation of PME group 1, PME group 2, and PME inhibitor transcript expression and total PME activity. The regulatory patterns indicated a role for PME activity in testa rupture (TR). Consistent with a role for cell wall pectin methylesterification in TR, treatment of seeds with PME resulted in enhanced testa permeability and promoted TR. Mathematical modeling of transcript expression changes in germinating garden cress and Arabidopsis (Arabidopsis thaliana) seeds suggested that group 2 PMEs make a major contribution to the overall PME activity rather than acting as PME inhibitors. It is concluded that regulated changes in the degree of pectin methylesterification through CAP- and RAD-specific PME and PME inhibitor expression play a crucial role during Brassicaceae seed germination. PMID:25429110

  12. Involvement of reactive oxygen species in endosperm cap weakening and embryo elongation growth during lettuce seed germination.

    PubMed

    Zhang, Yu; Chen, Bingxian; Xu, Zhenjiang; Shi, Zhaowan; Chen, Shanli; Huang, Xi; Chen, Jianxun; Wang, Xiaofeng

    2014-07-01

    Endosperm cap (CAP) weakening and embryo elongation growth are prerequisites for the completion of lettuce seed germination. Although it has been proposed that the cell wall loosening underlying these processes results from an enzymatic mechanism, it is still unclear which enzymes are involved. Here it is shown that reactive oxygen species (ROS), which are non-enzymatic factors, may be involved in the two processes. In Guasihong lettuce seeds imbibed in water, O2·(-) and H2O2 accumulated and peroxidase activity increased in the CAP, whereas its puncture force decreased. In addition, in the radicle, the increase in embryo growth potential was accompanied by accumulation of O2·(-) and an increase in peroxidase activity. Imbibing seeds in 0.3% sodium dichloroisocyanurate (SDIC) reduced endosperm viability and the levels of O2·(-), H2O2, and peroxidase activity in the CAP, whereas the decrease in its puncture force was inhibited. However, in the embryo, SDIC did not affect the accumulation of O2·(-), peroxidase activity, and the embryo growth potential. As a result, SDIC caused atypical germination, in which the endosperm ruptured at the boundary between the CAP and lateral endosperm. ROS scavengers and ROS generation inhibitors inhibited the CAP weakening and also decreased the embryo growth potential, thus decreasing the percentage of seed germination. Exogenous ROS and ROS generation inducers increased the percentage of CAP rupture to some extent, and the addition of H2O2 to 0.3% SDIC enabled some seeds to undergo typical germination. PMID:24744430

  13. A peroxisomal ABC transporter promotes seed germination by inducing pectin degradation under the control of ABI5.

    PubMed

    Kanai, Masatake; Nishimura, Mikio; Hayashi, Makoto

    2010-06-01

    Seed dormancy is essential for most plants to control the timing of germination. In Arabidopsis thaliana, PED3 is a single-copy gene encoding an ATP-binding cassette transporter that is required for peroxisomal fatty acid beta-oxidation. PED3 is involved in the import of several biologically important molecules into the peroxisome, including very-long-chain fatty acids associated with the breakdown of seed-reserve lipids, and precursors of auxin and jasmonic acid. The germination of ped3 mutants is significantly impaired, suggesting that PED3 regulates dormancy and germination. A transcriptome analysis revealed that many genes containing the core motif of the ABA responsive element (ABRE) in their promoter regions, and the ABA insensitive 5 (ABI5) transcription factor that binds to ABRE, are abnormally up-regulated in imbibed ped3 seeds. Expression of polygalacturonase inhibiting proteins (PGIPs) is also up-regulated specifically in ped3 after imbibition. By contrast, the ped3 abi5 double mutant does not show any of these expression patterns. The results indicate that the abi5 mutation normalizes PGIP expression and rescues the impaired germination phenotype of the ped3 mutant. PGIPs are known to act as inhibitors of polygalacturonases that degrade pectin. The amount of PGIP1 transcript regulates the timing of radicle protrusion. The impaired germination of ped3 could also be rescued by removal of pectin from the seed coat using exogenous polygalacturonase or acidic conditions. Overall, our results suggest that PED3, a peroxisomal ABC transporter, promotes seed germination by suppressing PGIPs under the control of ABI5. PMID:20345608

  14. Enhancement in the germination, growth and yield of okra (Abelmoschus esculentus) using pre-sowing magnetic treatment of seeds.

    PubMed

    Naz, Afshan; Jamil, Yasir; ul Haq, Zia; Iqbal, Munawar; Ahmad, Muhammad Raza; Ashraf, Muhammad Irfan; Ahmad, Rasheed

    2012-06-01

    The effect of pre-sowing magnetic treatments was investigated on germination, growth and yield of okra (Abelmoschus esculentus cv. Sapz pari). The dry okra seeds were exposed to sinusoidal magnetic field induced by an electromagnet. The average magnetic field exposure was 99 mT for 3 and 11 min and seeds with no magnetic field treatment were considered as control. Both treated and non-treated seeds were sown in experimental plots (120 m2) under similar conditions. Samples were collected at regular intervals for statistical analysis. A significant increase (P < 0.05) was observed in germination percentage, number of flowers per plant, leaf area (cm2), plant height (cm) at maturity, number of fruits per plant, pod mass per plant and number of seeds per plant. The 99 mT for 11 min exposure showed better results as compared to control. PMID:22803337

  15. Germination of Juniperus procera seeds in response to stratification and smoke treatments, and detection of insect-damaged seeds with VIS + NIR spectroscopy

    Microsoft Academic Search

    Mulualem Tigabu; Joakim Fjellström; Per Christer Odén; Demel Teketay

    2007-01-01

    Seeds of Juniperus procera collected from five provenances across its geographic range in Ethiopia were subjected to cold-moist stratification at 5°C\\u000a or 10°C for 6–12 weeks. The effect of aqueous smoke solution in overcoming the light requirement for germination, and the\\u000a potential of visible (VIS) and near infrared reflectance (NIR) spectroscopy for sorting sound and insect-damaged seeds were\\u000a also investigated. Highly

  16. Exogenous spermidine improves seed germination of white clover under water stress via involvement in starch metabolism, antioxidant defenses and relevant gene expression.

    PubMed

    Li, Zhou; Peng, Yan; Zhang, Xin-Quan; Ma, Xiao; Huang, Lin-Kai; Yan, Yan-Hong

    2014-01-01

    This study was designed to determine the effect of exogenous spermidine (Spd) (30 ?M) on white clover seed germination under water stress induced by polyethylene glycol 6000. Use of seed priming with Spd improved seed germination percentage, germination vigor, germination index, root viability and length, and shortened mean germination time under different water stress conditions. Seedling fresh weight and dry weight also increased significantly in Spd-treated seeds compared with control (seeds primed with distilled water). Improved starch metabolism was considered a possible reason for this seed invigoration, since seeds primed with Spd had significantly increased ?-amylase/?-amylase activities, reducing sugar, fructose and glucose content and transcript level of ?-amylase gene but not transcript level of ?-amylase gene. In addition, the physiological effects of exogenous Spd on improving seeds' tolerance to water deficit during germination were reflected by lower lipid peroxidation levels, better cell membrane stability and significant higher seed vigour index in seedlings. Enhanced antioxidant enzyme activities (superoxide dismutase, peroxidase, catalase and ascorbate peroxidase), ascorbate-glutathione cycle (ASC-GSH cycle) and transcript level of genes encoding antioxidant enzymes induced by exogenous Spd may be one of the critical reasons behind acquired drought tolerance through scavenging of reactive oxygen species (ROS) in water-stressed white clover seeds. The results indicate that Spd plays an important function as a stress-protective compound or physiological activator. PMID:25379640

  17. Switchgrass (Panicum virgatum L.) Intraspecific Variation and Thermotolerance Classification Using in Vitro Seed Germination Assay

    SciTech Connect

    Seepaul, Ramdeo; Macoon, Bisoondat; Reddy, K. Raja; Baldwin, Brian

    2011-05-17

    Cardinal temperatures for plant processes have been used for thermotolerance screening of genotypes, geoclimatic adaptability determination and phenological prediction. Current simulation models for switchgrass (Panicum virgatum L.) utilize single cardinal temperatures across genotypes for both vegetative and reproductive processes although in-tra-specific variation exists among genotypes. An experiment was conducted to estimate the cardinal temperatures for seed germination of 14 diverse switchgrass genotypes and to classify genotypes for temperature tolerance. Stratified seeds of each genotype were germinated at eight constant temperatures from 10���°C to 45���°C under a constant light inten-sity of 35 ���¼mol���·m�¢����2���·s�¢����1 for 12 h���·d�¢����1. Germination was recorded at 6-h intervals in all treatments. Maximum seed germi-nation (MSG) and germination rate (GR), estimated by fitting Sigmoidal function to germination-time series data, var-ied among genotypes. Quadratic and bilinear models best described the MSG and GR responses to temperature, re-spectively. The mean cardinal temperatures, Tmin, Topt, and Tmax, were 8.1, 26.6, and 45.1���°C for MSG and 11.1, 33.1, and 46.0���°C for GR, respectively. Cardinal temperatures for MSG and GR; however, varied significantly among geno-types. Genotypes were classified as sensitive (�¢����Cave-in-rock�¢����, �¢����Dacotah�¢����, �¢����Expresso�¢����, �¢����Forestburg�¢����, �¢����Kanlow�¢����, �¢����Sun-burst�¢����, �¢����Trailblazer�¢���� and �¢����Tusca�¢����), intermediate (�¢����Alamo�¢����, �¢����Blackwell�¢����, �¢����Carthage�¢����, �¢����Shawnee�¢����, and �¢����Shelter�¢����) and tol-erant (�¢����Summer�¢����) to high temperature based on cumulative temperature response index (CTRI) estimated by summing individual response indices estimated from the MSG and GR cardinal temperatures. Similarly, genotypes were also classified as sensitive (Alamo, Blackwell, Carthage, Dacotah, Shawnee, Shelter and Summer), moderately sensitive (Cave-in-rock, Forestburg, Kanlow, Sunburst, and Tusca), moderately tolerant (Trailblazer), and tolerant (Expresso) to low temperatures. The cardinal temperature estimates would be useful to improve switchgrass models for field applica-tions. Additionally, the identified cold- and heat-tolerant genotypes can be selected for niche environments and in switchgrass breeding programs to develop new genotypes for low and high temperature environments.

  18. The effect of Azotobacter vinelandii on plant seed germination and adhesion of these bacteria to cucumber roots

    Microsoft Academic Search

    I. K. Kurdish; Z. T. Bega; A. S. Gordienko; D. I. Dyrenko

    2008-01-01

    Bacterization of seeds of several plant species with Azotobacter vinelandii suspension stimulates their germination to different degrees. This demonstrates that seeds of different species display different\\u000a sensitivity to the biologically active substances accumulating in the culture liquid of these bacteria. The adhesion patterns\\u000a of these bacteria to cucumber roots were studied. The maximal number of cells adhered to the root

  19. Accumulation of Vacuolar H+Pyrophosphatase and H+ATPase during Reformation of the Central Vacuole in Germinating Pumpkin Seeds

    Microsoft Academic Search

    Masayoshi Maeshima; Yuka Takeuchi; Mikio Nishimura

    1994-01-01

    Protein storage vacuoles were examined for the induction of H+- pyrophosphatase (H+-PPase), H+-ATPase, and a membrane integral protein of 23 kD after seed germination. Membranes of protein storage vacuoles were prepared from dry seeds and etiolated cotyledons of pumpkin (Cucurbits sp.). Membrane vesicles from etiolated cotyledons had ATP- and pyrophosphate-dependent H+- transport activities. H+-ATPase activity was sensitive to nitrate and

  20. Interaction between a plant-derived smoke extract, light and phytohormones on the germination of light-sensitive lettuce seeds

    Microsoft Academic Search

    J. Staden; A. K. Jäger; A. Strydom

    1995-01-01

    Plant-derived smoke extracts mimics the effect of red light on germination in light-sensitive lettuce seeds and partially overcomes the inhibitory effect of far-red light. Interaction between a smoke extract and gibberellins, cytokinins, abscisic acid and ethephon was investigated. Smoke acted synergistically with GA3 and increased the sensitivity of the lettuce seeds to ABA. It seems likely that smoke affects membrane

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

    Microsoft Academic Search

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

    2009-01-01

    Low temperature stress during germination and early seedling growth is an important constraint of global production of maize.\\u000a The effects of seed priming with 0.25%, 0.50%, and 0.75% (w\\/v) chitosan solutions at 15 °C on the growth and physiological\\u000a changes were investigated using two maize (Zea mays L.) inbred lines, HuangC (chilling-tolerant) and Mo17 (chilling-sensitive). While seed priming with chitosan

  2. Translatome profiling in dormant and nondormant sunflower (Helianthus annuus) seeds highlights post-transcriptional regulation of germination.

    PubMed

    Layat, Elodie; Leymarie, Juliette; El-Maarouf-Bouteau, Hayat; Caius, José; Langlade, Nicolas; Bailly, Christophe

    2014-12-01

    Seed dormancy, which blocks germination in apparently favourable conditions, is a key regulatory control point of plant population establishment. As germination requires de novo translation, its regulation by dormancy is likely to be related to the association of individual transcripts to polysomes. Here, the polysome-associated mRNAs, that is, the translatome, were fractionated and characterized with microarrays in dormant and nondormant sunflower (Helianthus annuus) embryos during their imbibition at 10°C, a temperature preventing germination of dormant embryos. Profiling of mRNAs in polysomal complexes revealed that the translatome differs between germinating and nongerminating embryos. Association of transcripts with polysomes reached a maximum after 15 h of imbibition; at this time-point 194 polysome-associated transcripts were specifically found in nondormant embryos and 47 in dormant embryos only. The proteins corresponding to the polysomal mRNAs in nondormant embryos appeared to be very pertinent for germination and were involved mainly in transport, regulation of transcription or cell wall modifications. This work demonstrates that seed germination results from a timely regulated and selective recruitment of mRNAs to polysomes, thus opening novel fields of investigation for the understanding of this developmental process. PMID:25157915

  3. Seed size variation and its effect on germination and seedling performance in the clonal herb Convallaria majalis

    NASA Astrophysics Data System (ADS)

    Eriksson, Ove

    1999-02-01

    Variation in seed size is common both within and among plant species. This study examined within-species variation in seed weight, and its implications for some components of fitness in the clonal herb Convallaria majalis. This species produces berries containing 4.1 seeds on average. The average seed weight was 16.5 mg, with a coefficient of variation of 32.7%. Seed packaging in fruits was on average 12.5%, and showed a slight tendency to increase with fruit weight. A trade-off was found between seed weight and seed number both within fruits and within ramets. The probability and timing of germination was not influenced by seed size. A field experiment and indirect evidence suggested that post-dispersal seed predation was not related to seed size. Increasing seed weight conferred an advantage to developing seedlings. This advantage was enhanced if a seedling was growing in the close vicinity of a seedling of another species. It is suggested that seed size variation in C. majalis primarily is the result of resource variation during fruit development. A conflict between parents and offspring may however contribute to increase seed size variation.

  4. How membranes organize during seed germination: three patterns of dynamic lipid remodelling define chilling resistance and affect plastid biogenesis.

    PubMed

    Yu, Xiaomei; Li, Aihua; Li, Weiqi

    2015-07-01

    Imbibitional chilling injury during germination causes agricultural losses, but this can be overcome by osmopriming. It remains unknown how membranes reorganize during germination. Herein, we comparatively profiled changes of membrane lipids during imbibition under normal and chilling temperatures in chilling-tolerant and -sensitive soybean seeds. We found three patterns of dynamic lipid remodelling during the three phases of germination. Pattern 1 involved a gradual increase in plastidic lipids during phases I and II, with an abrupt increase during phase III. This abrupt increase was associated with initiation of photosynthesis. Pattern 3 involved phosphatidic acid (PA) first decreasing, then increasing, and finally decreasing to a low level. Patterns 1 and 3 were interrupted in chilling-sensitive seeds under low temperature, which lead a block in plastid biogenesis and accumulation of harmful PA, respectively. However, they were rescued and returned to their status under normal temperature after polyethylene glycol osmopriming. We specifically inhibited phospholipase D (PLD)-mediated PA formation in chilling-sensitive seeds of soybean, cucumber, and pea, and found their germination under low temperature was significantly improved. These results indicate that membranes undergo specific and functional reorganization of lipid composition during germination and demonstrate that PLD-mediated PA causes imibibitional chilling injury. PMID:25474382

  5. Environment sensing in spring-dispersed seeds of a winter annual Arabidopsis influences the regulation of dormancy to align germination potential with seasonal changes.

    PubMed

    Footitt, Steven; Clay, Heather A; Dent, Katherine; Finch-Savage, William E

    2014-05-01

    Seed dormancy cycling plays a crucial role in the lifecycle timing of many plants. Little is known of how the seeds respond to the soil seed bank environment following dispersal in spring into the short-term seed bank before seedling emergence in autumn. Seeds of the winter annual Arabidopsis ecotype Cvi were buried in field soils in spring and recovered monthly until autumn and their molecular eco-physiological responses were recorded. DOG1 expression is initially low and then increases as dormancy increases. MFT expression is negatively correlated with germination potential. Abscisic acid (ABA) and gibberellin (GA) signalling responds rapidly following burial and adjusts to the seasonal change in soil temperature. Collectively these changes align germination potential with the optimum climate space for seedling emergence. Seeds naturally dispersed to the soil in spring enter a shallow dormancy cycle dominated by spatial sensing that adjusts germination potential to the maximum when soil environment is most favourable for germination and seedling emergence upon soil disturbance. This behaviour differs subtly from that of seeds overwintered in the soil seed bank to spread the period of potential germination in the seed population (existing seed bank and newly dispersed). As soil temperature declines in autumn, deep dormancy is re-imposed as seeds become part of the persistent seed bank. PMID:24444091

  6. Effect of shade on seed protein oil fatty acids and minerals in soybean lines varying in seed germinability in the Early Soybean Production System

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The cause of poor seed quality (germination) of soybean produced in the Early Soybean Production System in the midsouth U.S.A. is still not completely understood. Temperature, solar radiation, and soybean genotype may all be important factors involved. The objective of this research was to evaluate...

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. Flavonoids from leaves of Derris urucu: assessment of potential effects on seed germination and development of weeds.

    PubMed

    Silva, Ewerton A S da; Lôbo, Lívia T; Silva, Geilson A da; Souza Filho, Antonio Pedro Da S; Da Silva, Milton N; Arruda, Alberto C; Guilhon, Giselle M S P; Santos, Lourivaldo S; Arruda, Mara S P

    2013-09-01

    In some previous studies, we described the isolation of nine compounds from leaves of Derris urucu, a species found widely in the Amazon rainforest, identified as five stilbenes and four dihydroflavonols. In this work, three of these dihydroflavonols [urucuol A (1), urucuol B (2) and isotirumalin (3)] were evaluated to identify their potential as allelochemicals, and we are also reporting the isolation and structural determination of a new flavonoid [5,3'-dihydroxy-4'-methoxy-(7,6:5?,6?)-2?,2?-dimethylpyranoflavanone (4)]. We investigated the effects of the dihydroflavonols 1-3 on seed germination and radicle and hypocotyl growth of the weed Mimosa pudica, using solutions at 150 mg.L-1. Urucuol B, alone, was the substance with the greatest potential to inhibit seed germination (26%), while isotirumalin showed greater ability to reduce the development of the hypocotyl (25%), but none of the three substances showed the potential to inhibit radicle. When combined in pairs, the substances showed synergism for the development of root and hypocotyl and effects on seed germination that could be attributed to antagonism. When tested separately, the trend has become more intense effects on seed germination, while for the substances tested in pairs, the intensity of the effect was greater on development of weed. PMID:24068080

  9. Molecular characterization of the fatty alcohol oxidation pathway for wax-ester mobilization in germinated jojoba seeds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Jojoba (Simmondsia chinensis) is the only plant species known to use liquid wax esters (WE) as a primary seed storage reserve. Upon germination, WE hydrolysis releases very long-chain fatty alcohols, which must be oxidised to fatty acids by the sequential action of a fatty alcohol oxidase (FAO) and ...

  10. Effect of some light rare earth elements on seed germination, seedling growth and antioxidant metabolism in Triticum durum

    Microsoft Academic Search

    Luigi d’Aquino; Maria Concetta de Pinto; Luca Nardi; Massimo Morgana; Franca Tommasi

    2009-01-01

    Rare earth elements (REEs) enriched fertilizers have been commonly used in China since the 1980s, thus inducing a growing concern about their environmental impact in agriculture. In this work, the effect of some light REEs nitrate mixture and La3+ nitrate on seed germination, seedling growth and antioxidant metabolism in Triticum durum was investigated with the aim of clarifying the potential

  11. Changes in trigonelline (N-methylnicotinic acid) content and nicotinic acid metabolism during germination of mungbean (Phaseolus aureus) seeds

    Microsoft Academic Search

    Xin-qiang Zheng; Etsuko Hayashibe; Hiroshi Ashihara

    2005-01-01

    Changes in trigonelline content and in biosynthetic activity were determined in the cotyledons and embry- onic axes of etiolated mungbean (Phaseolus aureus) seedlings during germination. Accumulation of trigo- nelline (c. 240 nmol per pair of cotyledons) was observed in the cotyledons of dry seeds; trigonelline content decreased 2 d after imbibition. Trigonelline content in the embryonic axes increased with seedling

  12. Assessment of heavy metals phytotoxicity using seed germination and root elongation tests: A comparison of two growth substrates

    Microsoft Academic Search

    M. Di Salvatore; A. M. Carafa; G. Carratù

    2008-01-01

    Seed germination and root elongation test is used to evaluate hazardous waste sites and to assess toxicity of organic and inorganic compounds. Paper substrate, especially circular filter paper placed inside a Petri dish has long been used for this test. Same reports indicate that filter paper might interfere with the toxicity of inorganic substances, especially metal cations.This study evaluate toxicity

  13. Abscisic acid controls embryo growth potential and endosperm cap weakening during coffee ( Coffea arabica cv. Rubi) seed germination

    Microsoft Academic Search

    E. A. Amaral da Silva; Peter E. Toorop; Adriaan C. van Aelst; Henk W. M. Hilhorst

    2004-01-01

    The mechanism and regulation of coffee seed germination were studied in Coffea arabica L. cv. Rubi. The coffee embryo grew inside the endosperm prior to radicle protrusion and abscisic acid (ABA) inhibited the increase in its pressure potential. There were two steps of endosperm cap weakening. An increase in cellulase activity coincided with the first step and an increase in

  14. Spatial variation in temperature thresholds during seed germination of remnant Festuca hallii populations across the Canadian prairie

    Microsoft Academic Search

    Jie Qiu; Yuguang Bai; Yong-Bi Fu; John F. Wilmshurst

    2010-01-01

    Grassland in North America is expected to expand northward as the climate becomes warmer and drier under many climate change scenarios. Successful adaptation of plant species to climate change depends on regeneration success. This paper aims to identify the spatial variation in seed germination characteristics of Festuca hallii populations and to quantify the effect of genetic, geographic, demographic, or climatic

  15. INTERACTION OF METHYL-TERT BUTYL ETHER AND WATER STRESS ON SEED GERMINATION AND SEEDLING GROWTH IN SOIL MICROCOSMS

    EPA Science Inventory

    Methyl tert-butyl ether (MTBE) is a widespread contaminant in surface and ground water in the United States. Frequently irrigation is used to water fields to germinate planted seeds and sustain plant growth. A likely possibility exists that water used may have some MTBE. Our s...

  16. Effects of light treatment on isoflavone content of germinated soybean seeds.

    PubMed

    Phommalth, Siviengkhek; Jeong, Yeon-Shin; Kim, Yong-Hoon; Dhakal, Krishna Hari; Hwang, Young-Hyun

    2008-11-12

    Our research objective was to increase isoflavone content in the germinated soybean seeds of four different varieties (Pungsannamulkong, Cheongjakong, Aga4, and Aga3) by optimizing light treatments (dark, greenhouse, fluorescent, incandescent, and ultraviolet lamps). The results demonstrated that the highest isoflavone content was produced from the Aga3 variety, which was developed by an interspecific cross between Eunhakong (Glycine max) and KLG10084 (G. soja) at the Plant Genetic Laboratory, Kyunpook National University. Aga3 is known to have one of the highest isoflavone content in the world at present. Our results recommend exposure of 7-day-old Aga3 sprouts to a combined light treatment of greenhouse lamps (12 h per day) and ultraviolet light (40 min per day) for maximum isoflavone production. Aga3 produced high levels of isoflavone because, in part, it contained very high isoflavone levels within the seed as compared with the other varieties. Under stress conditions, Aga3 could produce over 1.90 times more isoflavone than its seed content and 1.53 times more isoflavone than when grown under dark conditions. PMID:18841981

  17. Effect of seed depth on germination and growth of velvetleaf (Abutilon theophrasti Medic.).

    PubMed

    Nagy, V; Nádasy, E; Lehoczky, E

    2010-01-01

    Importance of several weed species has been considerably increased during the last few decades in Hungary. Velvetleaf (Abutilon theophrasti Medic.) belongs to this spreading weed group as well. This weed species was in the 27th position in the course of the fourth Hungarian weed survey, but at the time of the fifth weed survey in 2007-2008 it stepped forward to the 10th position in the cornfields of Zala County. Requiring a warm climate, global climate warming plays a significant role in its rapid spread. Moreover, its effective reproduction strategy supports its occurrence and continuous spread in almost all field crops. Protection against velvetleaf can only be successful, if we know its biological and ecological characteristics. Comprehensive knowledge of the plant and selection of a proper application of weed control methods together can result velvetleaf free crop fields. The experiment was set up on the 29th of April 2009 at Keszthely where fifty seeds were sown into 50 litres volume plastic pots, in four replications with fifty pieces of seed per each plot. Germination percent of velvetleaf seeds and several growth indexes of seedlings (stem- and root length, leaf area, number of leaves, stem- and root fresh and dry weight) were measured on three different sampling dates. PMID:21542475

  18. Influence of pulsed magnetic field on soybean (Glycine max L.) seed germination, seedling growth and soil microbial population.

    PubMed

    Radhakrishnan, Ramalingam; Kumari, Bollipo Dyana Ranjitha

    2013-08-01

    The effects of pulsed magnetic field (PMF) treatment of soybean (Glycine max L. cv CO3) seeds were investigated on rate of seed germination, seedling growth, physico-chemical properties of seed leachates and soil microbial population under laboratory conditions. Seeds were exposed to PMF of 1500 nT at 0.1, 1.0 10.0 and 100.0 Hz for 5 h per day for 20 days, induced by enclosure coil systems. Non-treated seeds were considered as controls. All PMF treatments significantly increased the rate of seed germination, while 10 and 100 Hz PMFs showed the most effective response. The 1.0 and 10 Hz PMFs remarkably improved the fresh weight of shoots and roots, leaf area and plant height from seedlings from magnetically-exposed seeds compared to the control, while 10 Hz PMF increased the total soluble sugar, total protein and phenol contents. The leaf chlorophyll a, b and total chlorophyll were higher in PMF (10 and 100 Hz) pretreated plants, as compared to other treatments. In addition, activities of alpha-amylase, acid phosphatase, alkaline phosphatase, nitrate reductase, peroxidase and polyphenoloxidase were increased, while beta-amylase and protease activities were declined in PMF (10 Hz)-exposed soybean plants. Similarly, the capacity of absorbance of water by seeds and electrical conductivity of seed leachates were significantly enhanced by 10 Hz PMF exposure, whereas PMF (10 Hz) pretreated plants did not affect the microbial population in rhizosphere soil. The results suggested the potential of 10 Hz PMF treatment to enhance the germination and seedling growth of soybean. PMID:24772951

  19. Role of hematin and sodium nitroprusside in regulating Brassica nigra seed germination under nanosilver and silver nitrate stresses.

    PubMed

    Amooaghaie, Rayhaneh; Tabatabaei, Fatemeh; Ahadi, Ali-Mohammad

    2015-03-01

    Silver nanoparticles (AgNPs) are one of the most widely used nanomaterials, although the mechanisms of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and AgNO3 on Brassica nigra seed germination at physiological and molecular levels. Both AgNPs and AgNO3 inhibited seed germination, lipase activity, soluble and reducing sugar contents in germinating seeds and seedlings. These reductions were more pronounced in AgNP treatments than AgNO3 treatments. Application of 200-400mg/L both AgNPs and AgNO3 increased transcription of heme oxygenase-1. However, at 800, 1600 mg/L, AgNPs or AgNO3 suppressed HO-1 expression. At 400mg/L, AgNPs or AgNO3-induced inhibitory effects on seed germination and were ameliorated by the HO-1 inducer, hematin, or NO donor, sodium nitroprusside (SNP). Additionally, 4 ?M hematin and 400 ?M SNP were able to markedly boost the HO/NO system. However, the addition of the HO-1 inhibitor (ZnPPIX) or the specific scavenger of NO (cPTIO) not only reversed the protective effects conferred by hematin, but also blocked the up-regulation of HO activity. In addition, hematin-drived NO production in B. niger seeds under AgNPs was confirmed. Our results at physiological and molecular levels suggested that AgNPs were more toxic than AgNO3. Based on these results, for the first time, we suggest that endogenous HO is needed to alleviate AgNPs-induced germination inhibition, which might have a possible interaction with NO. PMID:25528376

  20. Age-related changes in protein metabolism of beech (Fagus sylvatica L.) seeds during alleviation of dormancy and in the early stage of germination.

    PubMed

    Ratajczak, Ewelina; Kalemba, Ewa M; Pukacka, Stanislawa

    2015-09-01

    The long-term storage of seeds generally reduces their viability and vigour. The aim of this work was to evaluate the effect of long-term storage on beech (Fagus sylvatica L.) seeds at optimal conditions, over 9 years, on the total and soluble protein levels and activity of proteolytic enzymes, including endopeptidases, carboxypeptidases and aminopeptidases, as well as free amino acid levels and protein synthesis, in dry seeds, after imbibition and during cold stratification leading to dormancy release and germination. The same analyses were conducted in parallel on seeds gathered from the same tree in the running growing season and stored under the same conditions for only 3 months. The results showed that germination capacity decreased from 100% in freshly harvested seeds to 75% in seeds stored for 9 years. The levels of total and soluble proteins were highest in freshly harvested seeds and decreased significantly during storage, these proportions were retained during cold stratification and germination of seeds. Significant differences between freshly harvested and stored seeds were observed in the activities of proteolytic enzymes, including endopeptidases, aminopeptidases and carboxypeptidases, and in the levels of free amino acids. The neosynthesis of proteins during dormancy release and in the early stage of seed germination was significantly weaker in stored seeds. These results confirm the importance of protein metabolism for seed viability and the consequences of its reduction during seed ageing. PMID:26071872

  1. Soil seed-bank structure and seed-germination dynamics contribute to pulsed shrub encroachment in a grassland-shrubland Chihuahuan ecotone

    NASA Astrophysics Data System (ADS)

    Moreno de las Heras, Mariano; Turnbull, Laura; Wainwright, John

    2015-04-01

    Shrub encroachment is pervasive in many arid and semi-arid landscapes worldwide. Large areas of desert grasslands in southwestern USA have shifted to sparse shrublands dominated by woody species over the last 150 years, accompanied by accelerated soil erosion. A complex range of mechanisms has been suggested to explain the occurrence of this phenomenon, including land-use change, climate variations, and soil erosion feedbacks of vegetation change. An important step to understand patterns in species dominance at desert grassland-shrubland transitions is the understanding of limitations on plant establishment imposed by the shrub-encroachment process. We analyze the structure of soil seed banks and the environmental limitations for seed germination (i.e. soil-water availability and temperature) of dominant species (black grama and creosotebush) across a Chihuahuan grassland-shrubland ecotone (Sevilleta National Wildlife Refuge, New Mexico). Seed density in soils across the ecotone is generally low (200-400 seeds m-2), although is largely concentrated in vegetation clumps (reaching peaks up to 800-1200 seeds m-2 in grass and shrub patches). Species composition in the soil seed-bank is strongly affected by shrub encroachment, with seed densities of grass species (and particularly for black grama) sharply decreasing in shrub-dominated areas. Optimal temperature for seed germination of both black grama and creosotebush (20-25°C) suggests synchronization of plant establishment with the summer monsoonal period. Water-level limitations for seed germination are similar for the two species (about 8-10% soil moisture), although creosotebush seeds need a longer time under optimal water-availability conditions for germination (about 12 days) than black grama seeds (about 7 days). Analysis of temporal series of field-based and simulated soil-moisture levels suggests that creosotebush requires very strong monsoonal precipitation for plant establishment, and therefore shrub encroachment is likely to take place in the form of low-frequent discrete pulses driven by the coupling of shrub dynamics at the seedling establishment and adult plant stages. Reestablishment of black grama is strongly limited by the lack of viable seeds in shrub-dominated areas.

  2. Common gas phase molecules from fungi affect seed germination and plant health in Arabidopsis thaliana

    PubMed Central

    2014-01-01

    Fungal volatile organic compounds (VOCs) play important ecophysiological roles in mediating inter-kingdom signaling with arthropods but less is known about their interactions with plants. In this study, Arabidopsis thaliana was used as a model in order to test the physiological effects of 23 common vapor-phase fungal VOCs that included alcohols, aldehydes, ketones, and other chemical classes. After exposure to a shared atmosphere with the 23 individual VOCs for 72 hrs, seeds were assayed for rate of germination and seedling formation; vegetative plants were assayed for fresh weight and chlorophyll concentration. All but five of the VOCs tested (1-decene, 2-n-heptylfuran, nonanal, geosmin and -limonene) had a significant effect in inhibiting either germination, seedling formation or both. Seedling formation was entirely inhibited by exposure to 1-octen-3-one, 2-ethylhexanal, 3-methylbutanal, and butanal. As assayed by a combination of fresh weight and chlorophyll concentration, 2-ethylhexanal had a negative impact on two-week-old vegetative plants. Three other compounds (1-octen-3-ol, 2-ethylhexanal, and 2-heptylfuran) decreased fresh weight alone. Most of the VOCs tested did not change the fresh weight or chlorophyll concentration of vegetative plants. In summary, when tested as single compounds, fungal VOCs affected A. thaliana in positive, negative or neutral ways. PMID:25045602

  3. Gibberellins and Seed Development in Maize. I. Evidence That Gibberellin/Abscisic Acid Balance Governs Germination versus Maturation Pathways1

    PubMed Central

    White, Constance N.; Proebsting, William M.; Hedden, Peter; Rivin, Carol J.

    2000-01-01

    Abscisic acid (ABA) is required for the regulation of seed maturation in maize (Zea mays L.). Mutants blocked in ABA synthesis (such as viviparous-5) do not mature to quiescent, desiccation-tolerant seeds, but germinate on the ear midway through kernel development. Because gibberellins (GA) and ABA act antagonistically in many aspects of plant development, we hypothesized that ABA antagonizes a positive GA signal for precocious germination in maize. In these experiments, we show that a GA deficiency early in seed development, induced genetically or via biosynthesis inhibitors, suppresses vivipary in ABA-deficient developing kernels. The resulting seeds have both desiccation tolerance and storage longevity. Temporal analysis of GA accumulation in wild-type kernels revealed the accumulation of bioactive GA1 and GA3 prior to the peak in ABA content. We speculate that these GAs stimulate a developmental program leading to vivipary in the absence of normal amounts of ABA, and that a reduction of GA content re-establishes an ABA/GA ratio appropriate for suppression of germination and induction of maturation. In contrast, the induction of a GA deficiency did not suppress vivipary in viviparous-1 mutant kernels, suggesting that VP1 acts downstream of both GA and ABA in programming seed development. PMID:10759503

  4. Flavonoid profile of Lupinus mexicanus germinated seed extract and evaluation of its neuroprotective effect.

    PubMed

    Uribe-Gómez, José de Jesús; Zamora-Natera, Juan Francisco; Bañuelos-Pineda, Jacinto; Kachlicki, Piotr; Stobiecki, Maciej; García-López, Pedro Macedonio

    2014-11-01

    The aim of this study was to determine the flavonoid profile of Lupinus mexicanus germinated seed extract (PE) and to evaluate its effect as a phytoestrogen on the morphometric parameters of CA3 hippocampal neurons of ovariectomized rats (OVX). L. mexicanus seeds, germinated for 48 h, were homogenized and macerated using an 80% ethanol solution. The extract was analyzed by HPLC/MS-MS. Thirty young Wistar strain female rats (200±10 g) were randomly distributed into four groups: sham operated (S) treated with dimethyl sulfoxide (vehicle); ovariectomized and treated with 1250 ?g of PE extract (OVX-PE); ovariectomized and treated with 5 ?g estradiol benzoate (OVX-EB); and ovariectomized and vehicle treated (OVX). All substances were injected subcutaneously daily for 28 days. On day 29, the animals were sacrificed, perfused, and fixed to obtain the brains for histological processing. Each brain was cut and stained with hematoxylin and eosin. The thickness of the stratum oriens (SO), the nuclear diameter, and the neuronal density were measured in the hippocampus CA3 area. Nine different flavonoids and one non-identified compound were detected. The histological analysis demonstrated that the thickness of the SO was higher in the OVX-EB and S groups than in the OVX-PE and OVX groups (p?0.05); in addition, the nuclear diameters of the neurons in the OVX-EB and S groups were higher compared with the other groups (p?0.05). The OVX group had the highest cellular density among groups (p?0.05). Based on our results, the PE obtained did not have beneficial effects on CA3 hippocampal neurons. PMID:24723146

  5. Ethylene promotes germination of Arabidopsis seed under salinity by decreasing reactive oxygen species: evidence for the involvement of nitric oxide simulated by sodium nitroprusside.

    PubMed

    Lin, Yingchao; Yang, Lei; Paul, Matthew; Zu, Yuangang; Tang, Zhonghua

    2013-12-01

    Both ethylene and nitric oxide (NO) are involved in modulating seed germination in adverse environments. However, the mechanisms by which they interact and affect germination have not been explained. In this study, the relationship between ethylene and NO during germination of Arabidopsis seed under salinity was analysed. Application of exogenous 1-aminocyclopropane-1-carboxylate (ACC, a precursor of ethylene biosynthesis) or sodium nitroprusside (SNP, an NO donor) largely overcame the inhibition of germination induced by salinity. The effects of ACC and SNP were decreased by 2-phenyl-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (cPTIO), a specific NO scavenger, or by aminoisobutyric acid (AIB), an inhibitor of ethylene biosynthesis, indicating that ethylene and NO interact during germination under salinity. Further, we demonstrated that ACC increased NO production and that SNP greatly induced the expression of the ACS2 gene involved in ethylene synthesis in Arabidopsis seeds germinating under salinity stress, suggesting that each substance influences the production of the other. Application of exogenous ACC increased germination under oxidative stress induced by hydrogen peroxide (H2O2) while SNP had a much smaller effect on wild-type Arabidopsis (Col-0) and no effect on the ethylene insensitive mutant (ein3-1) seeds, respectively. This shows that NO increased germination under salinity indirectly through H2O2 acting via the ethylene pathway. The endogenous concentration of H2O2 was increased by salinity in germinating seeds but was decreased by exogenous ACC, which stimulated germination ultimately. To explain all these results and the regulation of germination of Arabidopsis seed under salinity we propose a model involving ethylene, NO and H2O2 interaction. PMID:24148906

  6. Mobile organic compounds in biochar - a potential source of contamination - phytotoxic effects on cress seed (Lepidium sativum) germination.

    PubMed

    Buss, Wolfram; Mašek, Ond?ej

    2014-05-01

    Biochar can be contaminated during pyrolysis by re-condensation of pyrolysis vapours. In this study two biochar samples contaminated by pyrolysis liquids and gases to a high degree, resulting in high volatile organic compound (high-VOC) content, were investigated and compared to a biochar with low volatile organic compound (low-VOC) content. All biochar samples were produced from the same feedstock (softwood pellets) under the same conditions (550 °C, 20 min mean residence time). In experiments where only gaseous compounds could access germinating cress seeds (Lepidium sativum), application amounts ranging from 1 to 30 g of high-VOC biochar led to total inhibition of cress seed germination, while exposure to less than 1 g resulted in only partial reduction. Furthermore, leachates from biochar/sand mixtures (1, 2, 5 wt.% of biochar) induced heavy toxicity to germination and showed that percolating water could dissolve toxic compounds easily. Low-VOC biochar didn't exhibit any toxic effects in either germination test. Toxicity mitigation via blending of a high-VOC biochar with a low-VOC biochar increased germination rate significantly. These results indicate re-condensation of VOCs during pyrolysis can result in biochar containing highly mobile, phytotoxic compounds. However, it remains unclear, which specific compounds are responsible for this toxicity and how significant re-condensation in different pyrolysis units might be. PMID:24608115

  7. The influence of lupin seed germination on the chemical composition and standardized ileal digestibility of protein and amino acids in pigs.

    PubMed

    Chilomer, K; Kasprowicz-Potocka, M; Gulewicz, P; Frankiewicz, A

    2013-08-01

    The germination process can modify the chemical composition of nutrients in seeds, which can influence the digestibility and utilization of sprouts in animal diets compared to raw seeds. The aims of research were to provide controlled germination process of lupin seeds, monitor the changes in seed composition and determine the influence of the germination on the coefficients of standardized ileal digestibility (SID) of crude protein and amino acids in growing pigs, compared to raw lupin seeds. The seeds of two lupin species were used: yellow (RYL) (Lupinus luteus, cv. Lord) and blue (RBL) (Lupinus angustifolius, cv. Graf). Germination was provided in the dark at 24°C for 4 days. Nutritional and antinutritional compositions of raw and germinated seeds (GYL and GBL, respectively) were analysed. Digestibility study was performed on pigs with an average body weight of 25 kg, and the pigs were surgically fitted with a T-cannula in the distal ileum, with chromic oxide as an indicator. Seed germination increased the crude protein and fibre concentrations, but reduced the levels of the ether extract, nitrogen-free extracts and all amino acids in protein. The content of alkaloids and raffinose family oligosaccharides decreased in both lupin species. Germination had no positive impact (p>0.05) on the SID of crude protein and amino acids. Germination of lupin seeds negatively influenced the SID of lysine and methionine (p<0.05). The results of the research revealed a decrease in the concentrations of antinutritional factors in the sprouts of yellow and blue lupins compared to raw seeds; however, no positive effect was observed on the coefficients of the standardized ileal apparent digestibility of protein and amino acids. PMID:22540870

  8. The influence of temperatures and mechanical treatments on pre- and post-emergence growth of plum seedlings and the role of seed coats in germination inhibition

    E-print Network

    Lipe, W. N

    1962-01-01

    seed coats. . prunus 8'cede do nO't have haX'd seed COatss Other seeds are impermeable to oxygen. The upper seed od. danthdom ds ths slane. doah easmpls od dshaped germination -due to oxygen impermeibility (8). Many grass seeds axe reported to...'have seed coats which prevent free oxygen exchange (3g). Tools, et. al. ($4. ) reviewed a number of gexmi- nation inhibitors which may be present in some seeds. Twenty-two species of plants are reported to contain inhibitors specifically in . the seeds...

  9. Development of the activities of enzymes of the isoprenoid pathway during early stages of pea-seed germination

    PubMed Central

    Green, T. R.; Baisted, D. J.

    1972-01-01

    The activities of individual enzymes of the isoprenoid pathway from mevalonate kinase to squalene synthetase in homogenates of seeds germinated up to 32h were assayed. Changes in the activity of each enzyme were observed and compared with the activity at the 2h germination stage. Activities of alkaline phosphatase and fructose 1,6-diphosphate aldolase were similarly measured to provide a reference for changes in the general metabolic activity of seeds during imbibition of water. Water uptake reached a plateau after 12h. The reference enzymes almost doubled in activity between 2 and 8h and thereafter their activities steadily declined. All of the enzymes of the isoprenoid pathway increased in activity between 2 and 6h and, thereafter, with the exception of the prenyltransferase, their activities remained relatively constant. With the prenyltransferase activity the initial increase was followed by a short plateau between 6 and 9h and then a second increase to a maximum between 14 and 16h. After 16h the activity declined. The relative activities of the isoprenoid enzymes at 16h of germination were mevalonate kinase>phosphomevalonate kinase>pyrophosphomevalonate decarboxylase?isopentenyl pyrophosphate isomerase>squalene synthetase>isopentenyl pyrophosphate/dimethylallyl pyrophosphate prenyltransferase. The finding that the prenyltransferase may be the rate-limiting enzyme in squalene synthesis from mevalonate is discussed in relation to regulation of isoprenoid synthesis during pea-seed germination. PMID:4348263

  10. Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains.

    PubMed

    de Melo, Risolandia Bezerra; Franco, Augusto César; Silva, Clovis Oliveira; Piedade, Maria Teresa Fernandez; Ferreira, Cristiane Silva

    2015-01-01

    Successful germination and seedling establishment are crucial steps for maintenance and expansion of plant populations and recovery from perturbations. Every year the Amazon River and its tributaries overflow and flood the adjacent forest, exerting a strong selective pressure on traits related to seedling recruitment. We examined seed characteristics, stored reserves, germination, seedling development and survival under water of eight representative tree species from the lower portions of the flood-level gradient to identify adaptive strategies that contribute to their regeneration in this extreme ecosystem. Submerged seedlings were assessed for longevity and survival until they showed symptoms of injury. At this point, the remaining healthy seedlings were planted in unsaturated soil to monitor recovery after re-exposure to air over 30 days. All small (seed mass ?0.17 g) seeds had epigeal phanerocotylar-type germination, a trait that would allow plants to acquire light and CO2 in the shortest time. Cell wall storage polysaccharide was a major component of all seeds, suggesting plant investment in structural reserves. Seven of the eight species germinated and formed healthy seedlings under water that endured submersion without any apparent injury for periods of 20-115 days, depending on the species. Seedlings of some species changed the direction of root growth and grew towards the surface of the water, which might have increased the uptake of oxygen to the tissues. Only one of the seven species did not survive re-exposure to air. Species able to germinate and produce seedlings under submersion, which subsequently are able to establish in aerated soils, would have more time available for terrestrial growth. This is critical for colonization of lower portions of the flood-level gradient where establishment is constrained by the short terrestrial phase that precedes the next flood. PMID:25922297

  11. Seed germination and seedling development in response to submergence in tree species of the Central Amazonian floodplains

    PubMed Central

    de Melo, Risolandia Bezerra; Franco, Augusto César; Silva, Clovis Oliveira; Piedade, Maria Teresa Fernandez; Ferreira, Cristiane Silva

    2015-01-01

    Successful germination and seedling establishment are crucial steps for maintenance and expansion of plant populations and recovery from perturbations. Every year the Amazon River and its tributaries overflow and flood the adjacent forest, exerting a strong selective pressure on traits related to seedling recruitment. We examined seed characteristics, stored reserves, germination, seedling development and survival under water of eight representative tree species from the lower portions of the flood-level gradient to identify adaptive strategies that contribute to their regeneration in this extreme ecosystem. Submerged seedlings were assessed for longevity and survival until they showed symptoms of injury. At this point, the remaining healthy seedlings were planted in unsaturated soil to monitor recovery after re-exposure to air over 30 days. All small (seed mass ?0.17 g) seeds had epigeal phanerocotylar-type germination, a trait that would allow plants to acquire light and CO2 in the shortest time. Cell wall storage polysaccharide was a major component of all seeds, suggesting plant investment in structural reserves. Seven of the eight species germinated and formed healthy seedlings under water that endured submersion without any apparent injury for periods of 20–115 days, depending on the species. Seedlings of some species changed the direction of root growth and grew towards the surface of the water, which might have increased the uptake of oxygen to the tissues. Only one of the seven species did not survive re-exposure to air. Species able to germinate and produce seedlings under submersion, which subsequently are able to establish in aerated soils, would have more time available for terrestrial growth. This is critical for colonization of lower portions of the flood-level gradient where establishment is constrained by the short terrestrial phase that precedes the next flood. PMID:25922297

  12. Control of alpha-Amylase Development in Cotyledons during and following Germination of Mung Bean Seeds.

    PubMed

    Morohashi, Y; Katoh, H; Kaneko, Y; Matsushima, H

    1989-09-01

    Developmental patterns of alpha-amylase in Vigna radiata cotyledons during and following germination were quite different depending on the differences in the treatments of cotyledons during the imbibitional stage. When axis-detached cotyledons were imbibed in water with seed-coats attached, alpha-amylase activity did not increase and remained low. On the other hand, when the cotyledons were imbibed in water after seed-coat removal, the enzyme activity increased markedly. If the axis was attached to the cotyledons, alpha-amylase showed a marked development even under the former imbibition conditions. These changes in the enzyme activity were in parallel with those in the enzyme content, and the content, in turn, was dependent upon the availability of mRNA for alpha-amylase. We propose that the regulation of the development of alpha-amylase in cotyledons may involve some factor(s) inhibitory to accumulation of alpha-amylase mRNA, which is present in dry cotyledons and can be removed from cotyledons by leakage or by the presence of the axis. PMID:16667006

  13. Biphasic Fluence-Response Curves for Phytochrome-Mediated Kalanchoë Seed Germination 1

    PubMed Central

    Rethy, Roger; Dedonder, Andrée; De Petter, Edwin; Van Wiemeersch, Luc; Fredericq, Henri; De Greef, Jan; Steyaert, Herman; Stevens, Hilde

    1987-01-01

    The fluence-response curves for the effect of two red pulses separated by 24 hours on the germination of Kalanchoe blossfeldiana Poelln. cv Vesuv seeds, incubated on gibberellic acid (GA3) are biphasic for suboptimal concentrations. The response in the low fluence range corresponds with a classical red/far-red reversible phytochrome mediated reaction. GA3 induces an additional response in the very low fluence range, which is also phytochrome mediated. The sensitivity to phytochrome-far-red absorbing form (Pfr), however, is increased about 20,000-fold, so that even far-red fluences become saturating. Both in the very low and low fluence response range, the maximal responses induced by saturating fluences are modulated by the GA3 concentration. GA3 having no direct influence on the phytochrome phototransformations, alters the Pfr requirement and determines the responding seed population fraction in the very low and low fluence range. The effet of GA3 appears to be on the transduction chain of the phytochrome signal. PMID:16665187

  14. Characterization of a radish introgression carrying the Ogura fertility restorer gene Rfo in rapeseed, using the Arabidopsis genome sequence and radish genetic mapping.

    PubMed

    Giancola, Sandra; Marhadour, Sylvie; Desloire, Sophie; Clouet, Vanessa; Falentin-Guyomarc'h, Hélène; Laloui, Wassila; Falentin, Cyril; Pelletier, Georges; Renard, Michel; Bendahmane, Abdelhafid; Delourme, Régine; Budar, Françoise

    2003-11-01

    The radish Rfo gene restores male fertility in radish or rapeseed plants carrying Ogura cytoplasmic male-sterility. This system was first discovered in radish and was transferred to rapeseed for the production of F1 hybrid seeds. We aimed to identify the region of the Arabidopsis genome syntenic to the Rfo locus and to characterize the radish introgression in restored rapeseed. We used two methods: amplified consensus genetic markers (ACGMs) in restored rapeseed plants and construction of a precise genetic map around the Rfo gene in a segregating radish population. The use of ACGMs made it possible to detect radish orthologs of Arabidopsis genes in the restored rapeseed genome. We identified radish genes, linked to Rfo in rapeseed and whose orthologs in Arabidopsis are carried by chromosomes 1, 4 and 5. This indicates several breaks in colinearity between radish and Arabidopsis genomes in this region. We determined the positions of markers relative to each other and to the Rfo gene, using the progeny of a rapeseed plant with unstable meiotic transmission of the radish introgression. This enabled us to produce a schematic diagram of the radish introgression in rapeseed. Markers which could be mapped both on radish and restored rapeseed indicate that at least 50 cM of the radish genome is integrated in restored rapeseed. Using markers closely linked to the Rfo gene in rapeseed and radish, we identified a contig spanning six bacterial artificial chromosome (BAC) clones on Arabidopsis chromosome 1, which is likely to carry the orthologous Rfo gene. PMID:12942173

  15. The N-end rule pathway promotes seed germination and establishment through removal of ABA sensitivity in Arabidopsis.

    PubMed

    Holman, Tara J; Jones, Peter D; Russell, Laurel; Medhurst, Anne; Ubeda Tomás, Susana; Talloji, Prabhavathi; Marquez, Julietta; Schmuths, Heike; Tung, Swee-Ang; Taylor, Ian; Footitt, Steven; Bachmair, Andreas; Theodoulou, Frederica L; Holdsworth, Michael J

    2009-03-17

    The N-end rule pathway targets protein degradation through the identity of the amino-terminal residue of specific protein substrates. Two components of this pathway in Arabidopsis thaliana, PROTEOLYSIS6 (PRT6) and arginyl-tRNA:protein arginyltransferase (ATE), were shown to regulate seed after-ripening, seedling sugar sensitivity, seedling lipid breakdown, and abscisic acid (ABA) sensitivity of germination. Sensitivity of prt6 mutant seeds to ABA inhibition of endosperm rupture reduced with after-ripening time, suggesting that seeds display a previously undescribed window of sensitivity to ABA. Reduced root growth of prt6 alleles and the ate1 ate2 double mutant was rescued by exogenous sucrose, and the breakdown of lipid bodies and seed-derived triacylglycerol was impaired in mutant seedlings, implicating the N-end rule pathway in control of seed oil mobilization. Epistasis analysis indicated that PRT6 control of germination and establishment, as exemplified by ABA and sugar sensitivity, as well as storage oil mobilization, occurs at least in part via transcription factors ABI3 and ABI5. The N-end rule pathway of protein turnover is therefore postulated to inactivate as-yet unidentified key component(s) of ABA signaling to influence the seed-to-seedling transition. PMID:19255443

  16. The regulation of ethylene biosynthesis and its apparent mode of action in germinating seeds of Latuca sativa, var. Premier Great Lakes

    E-print Network

    Dunlap, James Randolph

    1975-01-01

    THE REGULATION OF ETHYLENE BIOS YNTHESIS AND ITS APPARENT MODE OF ACTION IN GERMINATING SEEDS OF LATUCA SATIVA, VAR. PREMIER GREAT LAKES A Thesis by JAMES RANDOLPH DUNLAP Submitted to the Graduate College of Texas ABEAM University in partial... fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1975 Major Subject: Plant Physiology THE REGULATION OF ETHYLENE BIOSYNTHESIS AND ITS APPARENT MODE OF ACTION IN GERMINATING SEEDS OF LATUCA SATIVA, VAR. PREMIER GREAT LAKES A...

  17. Effect of in vivo administered plant growth hormones on the development of amylase and protease during germination of indian bean ( Dolichos lablab L. var. lignosus ) seeds

    Microsoft Academic Search

    Vadde Ramakrishna; P. Ramakrishna Rao

    2006-01-01

    The plant growth hormones — BA, GA3 or IAA (alone or in combination) in single dose were injected into the centre of intact imbibed seed, germinated in the presence\\u000a of water and monitored for root length, shoot length, and activities of ?-amylase and proteases during a 10-day germination\\u000a period of Indian bean seeds. A significant increase was noticed in the

  18. Effect of smoke, charred wood, and nitrogenous compounds on seed germination of ten species from woodland in central-western Spain.

    PubMed

    Pérez-Fernández, M A; Rodríguez-Echeverría, S

    2003-01-01

    The effect of smoke, charred wood, and nitrogenous compounds on germination was tested on 10 species of the Cistaceae, Poaceae, Fabaceae, and Asteraceae, from fire-prone, shrubby woodlands in central-western Spain. Dry seeds were exposed to smoke, by watering with distilled water-charred wood suspensions, or NaNO2, KNO3, NH4Cl, and NH4NO3. Smoke enhanced germination in 9 of 10 of the species. In species of Poaceae, germination was stimulated by 20 min of smoke exposure. In Asteraceae and Fabaceae species, 10 min of smoke exposure was the most effective treatment for enhancing germination. Three species--Cistus ladanifer, Cistus crispus, and Cistus monspeliensis--had a positive response to 20 min of smoke exposure; germination of Cistus salviifolius L. was also enhanced after 10 min. The effect of charred wood was variable, with no consistent germination pattern within the families. Trifolium angustifolium and Retama sphaerocarpa showed no stimulation of germination under most of the charred wood concentrations. Similarly, germination of Senecio jacobea under the charred wood treatment did not surpass that of the control. NaNO2 promoted seed germination in Dactylis glomerata (10 mM), Cistus ladanifer (1, 10, and 25 mM), and Cistus crispus (1 and 10 mM). KNO3 enhanced germination in Dactylis glomerata (1 and 25 mM), Dittrichia viscosa (10 and 25 mM), C. ladanifer (1, 10, and 25 mM), Cistus crispus (1 and 25 mM), and C. salviifolius aud C. monspeliensis (25 mM). NH4Cl induced germination of Dactylis glomerata and Dittrichia viscosa (1 mM), and Cistus species germinated best in 25 mM of this salt. NH4NO3 induced germination only in Cistus species. Holcus lanatus had the highest level of germination regardless of treatment. PMID:12647865

  19. Metal-binding particles alleviate lead and zinc toxicity during seed germination of metallophyte grass Astrebla lappacea.

    PubMed

    Rossato, L; MacFarlane, J; Whittaker, M; Pudmenzky, A; Doley, D; Schmidt, S; Monteiro, M J

    2011-06-15

    Combining metal-binding particles and metal-tolerant plants (metallophytes) offers a promising new approach for rehabilitation of heavy metal contaminated sites. Three types of hydrogel metal-binding polymer particles were synthesized and their effects on metal concentrations tested in vitro using metal ion solutions. The most effective of the tested polymers was a micron-sized thiol functional cross-linked acrylamide polymer which reduced the available solution concentrations of Pb(2+) (9.65 mM), Cu(2+) (4mM) and Zn(2+) (10mM) by 86.5%, 75.5% and 63.8%, respectively, and was able to store water up to 608% of its dry mass. This polymer was not toxic to seed germination. In deionised water, it enhanced seed germination, and at otherwise phytotoxic Pb(2+) (9.65 mM) and Zn(2+) (10mM) concentrations, it allowed normal germination and root elongation of the metallophyte grass Astrebla lappacea. We conclude that the polymer has the potential to facilitate restoration of heavy metal contaminated lands by reducing the concentration of metal cations in the soil solution and improving germination rates through reduced toxicity and enhanced plant water relations. PMID:21514726

  20. Effects of Copper Sulfate on Typha latifolia Seed Germination and Early Seedling Growth in Aqueous and Sediment Exposures

    Microsoft Academic Search

    S. L. Muller; D. B. Huggett

    2001-01-01

    The vascular macrophyte Typha latifolia Linnaeus (common cattail) may be a sentinel for evaluating potential phytotoxicity to rooted aquatic macrophytes in aquatic\\u000a systems. To further evaluate the potential utility of this species, T. latifolia seed germination, shoot growth, and root elongation were measured in 7-day aqueous exposures using mean measured aqueous\\u000a copper concentrations of 10.0, 23, 41, 62, 174, and