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1

Release of reactive oxygen intermediates (superoxide radicals, hydrogen peroxide, and hydroxyl radicals) and peroxidase in germinating radish seeds controlled by light, gibberellin, and abscisic acid.  

PubMed

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

Schopfer, P; Plachy, C; Frahry, G

2001-04-01

2

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

PubMed

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

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

2009-05-01

3

Easy PEAsy Seed Germination  

NSDL National Science Digital Library

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

Dyson, Paul

2012-04-09

4

Inactivation of Escherichia coli O157:H7 on Radish Seeds by Sequential Treatments with Chlorine Dioxide, Drying, and Dry Heat without Loss of Seed Viability ?  

PubMed Central

We developed and validated a treatment to inactivate Escherichia coli O157:H7 on radish seeds without decreasing seed viability. Treatments with aqueous ClO2 followed by drying and dry-heat treatments were evaluated for efficacy to inactivate the pathogen. Conditions to dry radish seeds after treatment with water (control) or ClO2 were established. When treated seeds with high water activity (aw) (>0.99) were stored at 45°C and 23% relative humidity (RH), the aw decreased to <0.30 within 24 h. Drying high-aw seeds before exposing them to dry-heat treatment (?60°C) was essential to preserve seed viability. The germination rate of radish seeds which had been immersed in water for 5 min, dried at 45°C and 23% RH for 24 h, and heated at 70°C for 48 h or at 80°C for 24 h was not significantly decreased (P ? 0.05) compared to that of untreated radish seeds. Sequential treatments with ClO2 (500 ?g/ml, 5 min), drying (45°C, 23% RH, 24 h), and dry heating (70°C, 23% RH, 48 h) eliminated E. coli O157:H7 (5.9 log CFU/g) on radish seeds and, consequently, sprouts produced from them without decreasing the germination rate. These sequential treatments are recommended for application to radish seeds intended for sprout production.

Bang, Jihyun; Kim, Haeyoung; Kim, Hoikyung; Beuchat, Larry R.; Ryu, Jee-Hoon

2011-01-01

5

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

PubMed

A protocol for producing transgenic radish (Raphanus sativus) was obtained by using both ultrasonic and vacuum infiltration assisted, Agrobacterium-mediated transformation. The Agrobacterium strain LBA4404 contained the binary vector pBI121-LEA (late embyogenesis abundant), which carried a Group 3 LEA gene, from Brassica napus. Among six combinations, Agrobacterium-mediated transformation assisted by a combination of 5-min sonication with 5-min vacuum infiltration resulted in the highest transformation frequency. The existence, integration and expression of transferred LEA gene in transgenic T(1) plants were confirmed by PCR, genomic Southern and Western blot analysis. Transgenic radish demonstrated better growth performance than non-transformed control plants under osmotic and salt stress conditions. Accumulation of Group 3 LEA protein in the vegetative tissue of transgenic radish conferred increased tolerance to water deficit and salt stress. PMID:15843933

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

2005-10-01

6

Seed Dormancy and Germination  

PubMed Central

Seed dormancy allows seeds to overcome periods that are unfavourable for seedling established and is therefore important for plant ecology and agriculture. Several processes are known to be involved in the induction of dormancy and in the switch from the dormant to the germinating state. The role of plant hormones, the different tissues and genes involved, including newly identified genes in dormancy and germination are described in this chapter, as well as the use transcriptome, proteome and metabolome analyses to study these mechanistically not well understood processes.

Bentsink, Leonie; Koornneef, Maarten

2008-01-01

7

Radishes  

NSDL National Science Digital Library

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.

N/A N/A (None;)

2007-07-04

8

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

PubMed

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

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

2003-05-01

9

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

Microsoft Academic Search

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)

Bolívar A. Cevallos-Casals; Luis Cisneros-Zevallos

2010-01-01

10

Compounds That Promote Seed Germination  

NSDL National Science Digital Library

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

11

EFFICACY OF FUNGICIDAL SEED TREATMENT IN CONTROLLING ALTERNARIA SPP. IN RADISH SEED  

Microsoft Academic Search

Islam, S.S., Rahman, M.H., Hasan, M.J., Ashadusjaman, M. and Khatun, M.M. 2007. Efficacy of Fungicidal Seed Treatment in Controlling Alternaria spp. in Radish Seed. Int. J. Sustain. Crop Prod. 2(5): 46-50 The experiments were conducted to find out effective seed treating fungicides to control seedborne Alternaria spp. of the crop. In the experiment, seeds were treated with the six fungicides

S. S. ISLAM; M. H. RAHMAN; M. J. HASAN

12

Effects of ageing on peroxidase activity and localization in radish (Raphanus sativus L.) seeds.  

PubMed

Peroxidase activity was assayed in crude extracts of integument, cotyledons and embryo axis of radish seeds, deteriorated under accelerated ageing conditions. Over five days of ageing, in which germination decreased from 100 to 52%, the enzyme activity in integument was higher than that in other seed parts, increasing in the first days of ageing and then decreasing sharply in extremely aged seeds. Polyacrylamide gel electrophoresis analysis showed four peroxidase isoenzymes with MM of 98, 52.5, 32.8 and 29.5 kDa in the embryo axis of unaged seeds, and only the 32.8 and 29.5 kDa MM isoforms in the integument and cotyledons. In these parts of the seed, only the 29.5 kDa MM isoenzyme increased in activity in early days of ageing and decreased there-after. In the embryo axis, the 29.5 kDa MM isoenzyme activity increased slowly in the first day of ageing, while the 98 and 52.5 kDa MM isoenzyme activities disappeared. A cytochemical localization of peroxidase activity in the various tissues showed that main differences between unaged and extremely aged seeds occurred in the embryo axis. PMID:12597620

Scialabba, A; Bellani, L M; Dell'Aquila, A

2002-01-01

13

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

Microsoft Academic Search

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

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

2001-01-01

14

Food safety evaluation of broccoli and radish sprouts  

Microsoft Academic Search

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

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

2008-01-01

15

Proteomics of rice seed germination  

PubMed Central

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

He, Dongli; Yang, Pingfang

2013-01-01

16

Gravitational stress on germinating Pinus pinea seeds.  

PubMed

In the germination of lipid-rich seeds, the glyoxylate cycle plays a control role in that, bypassing the two decarboxylative steps of the Krebs cycle; it allows the net synthesis of carbohydrates from lipids. The activity of isocitrate lyase, the key enzyme of the glyoxylate cycle, is an indicator of the state of seed germination: stage of germination, growth of embryo, activation and progress of protein synthesis, depletion of lipidic supplies. In order to investigate the effects of gravity on seed germination, we carried out a study on the time pattern of germination of Pinus pinea seeds that were subjected to a hypergravitational stress (1000 g for 64 h at 4 degrees C), either in a dry or in a wet environment, before to be placed in germination plates. During the whole time of germination, we monitored the state of embryo growth and the most representative enzymes of the main metabolic pathways. In treated wet seeds, we observed an average germination of only 20% with a slowdown of the enzyme activities assayed and a noticeable degradation of lipidic reserves with respect to the controls. These differences in germination are not found for dry seeds. PMID:14558475

Ranaldi, Francesco; Giachetti, Eugenio; Guerin, Elizabeth; Bacci, Stefano; Paoletti, Elena; Boddi, Vieri; Vanni, Paolo

2003-06-01

17

Oxygen requirement of germinating flax seeds.  

PubMed

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

Kuznetsov, Oleg A; Hasenstein, K H

2003-01-01

18

Oxygen requirement of germinating flax seeds  

NASA Astrophysics Data System (ADS)

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

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

2003-05-01

19

Photoinduced Seed Germination of Oenothera biennis L  

PubMed Central

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

Ensminger, Peter A.; Ikuma, Hiroshi

1988-01-01

20

Oxygen requirement of germinating flax seeds  

NASA Technical Reports Server (NTRS)

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.

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

2003-01-01

21

The oxygen requirement of germinating flax seeds  

NASA Astrophysics Data System (ADS)

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

Kuznetsov, O.; Hasenstein, K.

22

Germination, Respiration, and Adenylate Energy Charge of Seeds at Various Oxygen Partial Pressures  

PubMed Central

The effect of O2 partial pressure on the germination and the respiration of 12 cultivated species was studied. The reciprocal of the time necessary to observe rootlet emergence in 50% of the seeds was used to approach the germination rate. The maximum germination and respiration rates were reached in most seeds at O2 pressures close to that of air. Decreasing the O2 pressure produced a gradual decrease of the germination rate. The seeds could be classed in two groups according to their response to low O2 pressures. Group I includes lettuce, sunflower, radish, turnip, cabbage, flax, and soybean: at O2 pressures close to 2 kilopascals, the germination in this group was stopped and the adenylate energy charge was lower than 0.6. Group II includes rice, wheat, maize, sorghum, and pea. The germination rate of these seeds was also gradually decreased by lowering the O2 partial pressure but germination still occured, very slowly, at 0.1 kilopascal; the adenylate energy charge remained higher than 0.6. These differences in the germination rates and adenylate energy charge values could not be explained by differences in the sensitivity of respiration to O2.

Al-Ani, Ali; Bruzau, Francoise; Raymond, Philippe; Saint-Ges, Veronique; Leblanc, Jean Marc; Pradet, Alain

1985-01-01

23

Effects of Air Temperature on Seed Germination  

NSDL National Science Digital Library

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

Macarthur, Amy

24

EFFECT OF GERMINATION ON HEMP ( CANNABIS SATIVA L. ) SEED COMPOSITION  

Microsoft Academic Search

This study investigates the quantitative transformation that take place in hemp (Cannabis sativa L. ) seeds during germination: dry matter, ash, protein, lipid, fiber and carbohydrates, the Germinative Energy, the Germinative Capacity over eight days of germination. The results show that different components of the seed undergo transformations during germination. Germ grows by accumulating proteins and fiber and by consuming

SABIN-GEORGE ALBU; RADU MAR

25

Photoinduced Seed Germination of Oenothera biennis L  

PubMed Central

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.

Ensminger, Peter A.; Ikuma, Hiroshi

1987-01-01

26

Control of Seed Germination by Abscisic Acid  

PubMed Central

The germination process of mustard seeds (Sinapis alba L.) has been characterized by the time courses of water uptake, rupturing of the seed coat (12 hours after sowing), onset of axis growth (18 hours after sowing), and the point of no return, where the seeds lose the ability to survive redesiccation (12 to 24 hours after sowing, depending on embryo part). Abscisic acid (ABA) reversibly arrests embryo development at the brink of radicle growth initiation, inhibiting the water uptake which accompanies embryo growth. Seeds which have been kept dormant by ABA for several days will, after removal of the hormone, rapidly take up water and continue the germination process. Seeds which have been preincubated in water lose the sensitivity to be arrested by ABA after about 12 hours after sowing. This escape from ABA-mediated dormancy is not due to an inactivation of the hormone but to a loss of competence to respond to ABA during the course of germination. The sensitivity to ABA can be restored in these seeds by redrying. It is concluded that a primary action of ABA in inhibiting seed germination is the control of water uptake of the embryo tissues rather than the control of DNA, RNA, or protein syntheses.

Schopfer, P.; Bajracharya, D.; Plachy, C.

1979-01-01

27

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

NASA Astrophysics Data System (ADS)

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.

Hageseth, Gaylord T.

1982-02-01

28

Effects of Seed Treatments on Germination.  

National Technical Information Service (NTIS)

The goal of this study was to identify ways to stimulate the germination of seeds of various grasses and legumes of potential value in revegetation of army training grounds or similar damaged lands. Ten treatments (including a control) were used on ten sp...

D. Diemand A. J. Palazzo M. Sharif

1994-01-01

29

Germination Ecophysiology of Annona crassiflora Seeds  

PubMed Central

Background and Aims Little is known about environmental factors that break morphophysiological dormancy in seeds of the Annonaceae and the mechanisms involved. The aim of this study was to characterize the morphological and physiological components of dormancy of Annona crassiflora, a tree species native to the Cerrado of Brazil, in an ecophysiological context. Methods Morphological and biochemical characteristics of both embryo and endosperm were monitored during dormancy break and germination at field conditions. Seeds were buried in the field and exhumed monthly for 2 years. Germination, embryo length and endosperm digestion, with endo-?-mannanase activity as a marker, were measured in exhumed seeds, and scanning electron microscopy was used to detect cell division. The effect of constant low and high temperatures and exogenous gibberellins on dormancy break and germination was also tested under laboratory conditions. Key Results After burial in April, A. crassiflora seeds lost their physiological dormancy in the winter months with lowest monthly average minimum temperatures (May–August) prior to the first rainfall of the wet season. The loss of physiological dormancy enabled initiation of embryo growth within the seed during the first 2 months of the rainy season (September–October), resulting in a germination peak in November. Embryo growth occurred mainly through cell expansion but some dividing cells were also observed. Endosperm digestion started at the micropylar side around the embryo and diffused to the rest of the endosperm. Exogenous gibberellins induced both embryo growth and endo-?-mannanase activity in dormant seeds. Conclusions The physiological dormancy component is broken by low temperature and/or temperature fluctuations preceding the rainy season. Subsequent embryo growth and digestion of the endosperm are both likely to be controlled by gibberellins synthesized during the breaking of physiological dormancy. Radicle protrusion thus occurred at the beginning of the rainy season, thereby maximizing the opportunity for seedlings to emerge and establish.

da Silva, Edvaldo A. A.; de Melo, Daniel L. B.; Davide, Antonio C.; de Bode, Nienke; Abreu, Guilherme B.; Faria, Jose M. R.; Hilhorst, Henk W. M.

2007-01-01

30

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

PubMed

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

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

2009-01-01

31

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

PubMed

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

Mollard, Federico P O; Naeth, M Anne

2014-09-01

32

Are Radishes Really Allelopathic to Lettuce?  

ERIC Educational Resources Information Center

Presents an experiment that challenges the claim that sprouting radish seedlings release chemicals into the environment that inhibit germination of lettuce seeds. Reports that although no simple allelopathic demonstration was observed, the experiment provides fertile ground for further experimentation in inquiry-based laboratory experiences. (JRH)

Santaniello, Catherine M.; Koning, Ross E.

1996-01-01

33

Organic substance metabolism during seed germination of Pinus bungeana  

Microsoft Academic Search

The metabolism of fats, proteins and carbohydrates and change of enzyme of seeds ofpinus bungeana during the germination were conducted by the methods of gas-liquid chromatography, flow injection, colorimetric analysis\\u000a of spectrophotometer, to provide theoretical basis for seeds dormancy, germination and storage of seeds of forest tree. The\\u000a results indicate that (1) carbohydrates were first utilized during germination of seed

Shang Jie; Zhao Kentian

1993-01-01

34

Seed dormancy and germination in Melicytus ramiflorus (Violaceae)  

Microsoft Academic Search

The effects were studied of scarification (concentrated sulphuric acid for UP to 5 min), hching (for up to 2 h), stratification, and storage environment on germination of seed of the New Zealand endemic tree Melicytus ramflorus. Seeds that were incubated immediately after extraction from mature fruits germinated readi1y (87%), and leaching did not further enhance germination. Acid scarification only reduced

H. Herron; J. Clemens

2001-01-01

35

Effect of salicylic acid and salt on wheat seed germination  

Microsoft Academic Search

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

Aria Dolatabadian; Seyed Ali Mohammad Modarres Sanavy; Mozafar Sharifi

2009-01-01

36

[Research advance in seed germination of desert woody plants].  

PubMed

This paper reviewed the research methods of desert woody plants seed germination, and the effects of internal and external ecological factors on it. Most researchers use incubator and artificial climate chamber to dispose the seeds, while field investigation was few involved. Seed dormancy is the important physiological factor affecting germination, while seed size, mass and color are closely correlated with its maturity and vigor. The poor permeability of seed capsule is a barrier that restrains the germination, which can be weakened or eliminated by shaving, cutting, treating with low temperature, and dipping in chemical reagent, etc. Seed water content has a close correlation with its storage life and water-absorbing capability. Suitable temperature is the prerequisite of seed germination, while changing temperature can accelerate the germination. Soil moisture content is a limiting factor, while illumination is not so essential to the seed germination of most desert woody plants. Sand-burying plays an important role in the seed germination through regulating illumination, temperature, and soil moisture content. Salinity stress restrains the seed germination of desert woody plants observably. In further studies, the effects of multi-factors and the eco-physiological and molecular biological mechanisms of germination should be more concerned. PMID:17450753

Chang, Wei; Wu, Jian-guo; Liu, Yan-hong

2007-02-01

37

Nitric oxide accelerates seed germination in warm-season grasses.  

PubMed

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

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

2006-05-01

38

Promotion of Seed Germination by Nitrates and Cyanides  

Microsoft Academic Search

MANY viable seeds fail to germinate in darkness after imbibing water, but do so to varying degrees in solutions of several compounds. Well known promoters of germination are nitrate, nitrite and various sulphydryl and gibberellin salts1. Hydroxylammonium salts, although often cited as inhibitory1, are known to promote germination at low concentrations2. The essential action of none of these is understood

S. B. Hendricks; R. B. Taylorson

1972-01-01

39

Patterns of seed germination in Californian serpentine grassland species  

Microsoft Academic Search

Germination of nine Californian serpentine annual species and one perennial grass was examined as a function of soil and litter cover and seasonal timing of rainfall. Germination responses varied with the date of moisture application, and the patterns of variation differed among species. Germination occurred in waves over time, but in most of the species, virtually all the seeds had

S. L. Gulmon

1992-01-01

40

Investigating the Influence of Karrikins on Seed Germination  

ERIC Educational Resources Information Center

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.

de Beer, Josef

2012-01-01

41

Beta-amylase in germinating millet seeds.  

PubMed

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

Yamasaki, Yoshiki

2003-11-01

42

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

Microsoft Academic Search

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

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

2009-01-01

43

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

Microsoft Academic Search

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

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

2006-01-01

44

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

Microsoft Academic Search

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

M. A. Matus-Cádiz; P. Hucl

2005-01-01

45

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

PubMed

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

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

2013-01-15

46

IAA production during germination of Orobanche spp. seeds.  

PubMed

Broomrapes (Orobanche spp.) are parasitic plants, whose growth and development fully depend on the nutritional connection established between the parasite and the roots of the respective host plant. Phytohormones are known to play a role in establishing the specific Orobanche-host plant interaction. The first step in the interaction is seed germination triggered by a germination stimulant secreted by the host-plant roots. We quantified indole-3-acetic acid (IAA) and abscisic acid (ABA) during the seed germination of tobacco broomrape (Orobanche ramosa) and sunflower broomrape (O. cumana). IAA was mainly released from Orobanche seeds in host-parasite interactions as compared to non-host-parasite interactions. Moreover, germinating seeds of O. ramosa released IAA as early as 24 h after the seeds were exposed to the germination stimulant, even before development of the germ tube. ABA levels remained unchanged during the germination of the parasites' seeds. The results presented here show that IAA production is probably part of a mechanism triggering germination upon the induction by the host factor, thus resulting in seed germination. PMID:15310074

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

2004-07-01

47

Food safety evaluation of broccoli and radish sprouts.  

PubMed

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 of mesophilic, psychrotrophic, total and faecal coliform bacteria which are the usual counts for minimally processed germinated seeds. Putrescine, cadaverine, histamine, tyramine, spermidine and spermine increased during sprout production although these levels were below those permitted by legislation (5 mg/100 g of edible food). Broccoli and radish sprouts demonstrated no toxic effects on proliferation and viability of HL-60 cells and should be included in our diets as healthy and safe fresh foods. PMID:18314243

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

2008-05-01

48

Precocious Germination during In Vitro Growth of Soybean Seeds 1  

PubMed Central

Immature Glycine max (L.) Merrill seeds were grown and matured in liquid medium at 25°C under fluorescent light. In standard medium containing minerals, 146 millimolar sucrose and 62.5 millimolar glutamine (osmolality 0.24), precocious germination seldom occurred with a starting seed size of less than 300 milligrams fresh weight. Frequency of precocious germination increased with increased starting seed size. Sucrose concentration strongly affected precocious germination while glutamine concentration had no effect. Starting with 300 to 350 milligrams fresh weight seeds, treatments which reduced the sucrose concentration or lowered the osmolality of the culture medium stimulated precocious germination, and increased the fresh weight growth but not the dry weight growth of seeds. Increasing the osmolality to 0.38 with sucrose or mannitol prevented precocious germination without reducing dry weight accumulation in seeds. In medium with initially low osmolality, precocious germination was inhibited by addition of 1 to 100 micromolar abscisic acid to the medium without a reduction in seed growth. During growth and maturation of large soybean seeds in vitro, precocious germination and other abnormal tissue growth can be prevented by high sucrose or mannitol concentrations in the medium or by addition of abscisic acid.

Obendorf, Ralph L.; Wettlaufer, Scott H.

1984-01-01

49

Changes in flax ( Linum usitatissimum L.) seed lipids during germination  

Microsoft Academic Search

Flax (Linum usitatissimum L.) seeds were germinated for 8 d under laboratory conditions, and changes in their lipid fraction were studied by various\\u000a chemical and chromatographic methods. Total lipid content of the seeds was reduced fourfold at the end of the 8-d germination\\u000a period as compared to ungerminated seeds on a fresh weight basis. The neutral lipids comprised the major

P. K. J. P. D. Wanasundara; U. N. Wanasundara; F. Shahidi

1999-01-01

50

Brassinosteroids and gibberellins promote tobacco seed germination by distinct pathways  

Microsoft Academic Search

Seed germination of Nicotiana tabacum L. cv. Havana 425 is determined by the balance of forces between the growth potential of the embryo and the mechanical restraint of the micropylar endosperm. In contrast to the gibberellin GA4, the brassinosteroid (BR) brassinolide (BL) did not release photodormancy of dark-imbibed photodormant seeds. Brassinolide promoted seedling elongation and germination of non-photodormant seeds, but

Gerhard Leubner-Metzger

2001-01-01

51

Increased germination of diverse crop-wild hybrid sunflower seeds.  

PubMed

Gene flow from crop fields to wild populations produces hybrids that often differ from their wild counterparts in growth form, phenology, and life history characteristics. Germination and dormancy dynamics have a strong influence on population persistence, competitive dynamics, and ultimately, plant fitness. They may also play a role in modifying crop gene introgression, which has been of primary interest since the release of transgenic crops. We investigated how seed germination and dormancy were affected by sunflower crop wild hybridization in both laboratory and field experiments. Hybridization increased seed germination and decreased dormancy. Of the nine wild populations we assayed, most of their hybrids had higher germination than the wilds of the same population. However, absolute germination levels varied by population and testing environment. Hybrids produced by three different crop lines differed in germination, and their germination rankings shifted across populations. Increased germination in hybrids could accelerate crop gene introgression, provided that hybrids germinate in an appropriate period. Differences in relative germination of wild and hybrid seed indicated that the effect of germination on introgression will likely vary by population due, in part, to initial levels of dormancy in the population. Therefore, the implications of gene flow from crops with novel characteristics or from transgenic crops will also vary by population. PMID:16826985

Mercer, Kristin L; Shaw, Ruth G; Wyse, Donald L

2006-06-01

52

Variation of seed mass and its effects on germination in Polylepis australis : implications for seed collection  

Microsoft Academic Search

South American Polylepis mountain forests are recognised as being one of the most endangered forest ecosystems in the world. Reforestation measures\\u000a have been strongly recommended but may be hampered due to the very low seed germination reported for several Polylepis species. In order to facilitate reforestation we analysed the influence of seed mass on germination probability for Polylepis australis seeds

Peggy Seltmann; Ilona Leyer; Daniel Renison; Isabell Hensen

2007-01-01

53

Volatile Metabolites Controlling Germination in Buried Weed Seeds  

PubMed Central

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

Holm, Robert E.

1972-01-01

54

Plant hormone interactions during seed dormancy release and germination  

Microsoft Academic Search

This review focuses mainly on eudicot seeds, and on the interactions between abscisic acid (ABA), gibber- ellins (GA), ethylene, brassinosteroids (BR), auxin and cytokinins in regulating the interconnected molecular processes that control dormancy release and germi- nation. Signal transduction pathways, mediated by environmental and hormonal signals, regulate gene expression in seeds. Seed dormancy release and germination of species with coat

Birgit Kucera; Marc Alan Cohn; Gerhard Leubner-Metzger

2005-01-01

55

Purification and sequencing of radish seed calmodulin antagonists phosphorylated by calcium-dependent protein kinase.  

PubMed Central

A family of radish (Raphanus sativus) calmodulin antagonists (RCAs) was purified from seeds by extraction, centrifugation, batch-wise elution from carboxymethyl-cellulose, and high performance liquid chromatography (HPLC) on an SP5PW cation-exchange column. This RCA fraction was further resolved into three calmodulin antagonist polypeptides (RCA1, RCA2, and RCA3) by denaturation in the presence of guanidinium HCl and mercaptoethanol and subsequent reverse-phase HPLC on a C8 column eluted with an acetonitrile gradient in the presence of 0.1% trifluoroacetic acid. The RCA preparation, RCA1, RCA2, RCA3, and other radish seed proteins are phosphorylated by wheat embryo Ca(2+)-dependent protein kinase (CDPK). The RCA preparation contains other CDPK substrates in addition to RCA1, RCA2, and RCA3. The RCA preparation, RCA1, RCA2, and RCA3 inhibit chicken gizzard calmodulin-dependent myosin light chain kinase assayed with a myosin-light chain-based synthetic peptide substrate (fifty percent inhibitory concentrations of RCA2 and RCA3 are about 7 and 2 microM, respectively). N-terminal sequencing by sequential Edman degradation of RCA1, RCA2, and RCA3 revealed sequences having a high homology with the small subunit of the storage protein napin from Brassica napus and with related proteins. The deduced amino acid sequences of RCA1, RCA2, RCA3, and RCA3' (a subform of RCA3) have agreement with average molecular masses from electrospray mass spectrometry of 4537, 4543, 4532, and 4560 kD, respectively. The only sites for serine phosphorylation are near or at the C termini and hence adjacent to the sites of proteolytic precursor cleavage.

Polya, G M; Chandra, S; Condron, R

1993-01-01

56

Purification and sequencing of radish seed calmodulin antagonists phosphorylated by calcium-dependent protein kinase.  

PubMed

A family of radish (Raphanus sativus) calmodulin antagonists (RCAs) was purified from seeds by extraction, centrifugation, batch-wise elution from carboxymethyl-cellulose, and high performance liquid chromatography (HPLC) on an SP5PW cation-exchange column. This RCA fraction was further resolved into three calmodulin antagonist polypeptides (RCA1, RCA2, and RCA3) by denaturation in the presence of guanidinium HCl and mercaptoethanol and subsequent reverse-phase HPLC on a C8 column eluted with an acetonitrile gradient in the presence of 0.1% trifluoroacetic acid. The RCA preparation, RCA1, RCA2, RCA3, and other radish seed proteins are phosphorylated by wheat embryo Ca(2+)-dependent protein kinase (CDPK). The RCA preparation contains other CDPK substrates in addition to RCA1, RCA2, and RCA3. The RCA preparation, RCA1, RCA2, and RCA3 inhibit chicken gizzard calmodulin-dependent myosin light chain kinase assayed with a myosin-light chain-based synthetic peptide substrate (fifty percent inhibitory concentrations of RCA2 and RCA3 are about 7 and 2 microM, respectively). N-terminal sequencing by sequential Edman degradation of RCA1, RCA2, and RCA3 revealed sequences having a high homology with the small subunit of the storage protein napin from Brassica napus and with related proteins. The deduced amino acid sequences of RCA1, RCA2, RCA3, and RCA3' (a subform of RCA3) have agreement with average molecular masses from electrospray mass spectrometry of 4537, 4543, 4532, and 4560 kD, respectively. The only sites for serine phosphorylation are near or at the C termini and hence adjacent to the sites of proteolytic precursor cleavage. PMID:8278508

Polya, G M; Chandra, S; Condron, R

1993-02-01

57

Improving Seed Germination of Saltgrass under Saline Conditions  

Microsoft Academic Search

Saltgrass (Distichlis spicata var. stricta (Greene)) has a great potential for use as a turfgrass and as a revegetation species of saline sites. Experi- ments were conducted to test the effect of the application of different concentrations of ethep- hon, fusicoccin, kinetin, thiourea, and Proxy on saltgrass seed germination under three salinity levels. Saltgrass germination percentage was 56% under nonsaline

M. A. Shahba; Y. L. Qian; K. D. Lair

2008-01-01

58

Seed dormancy and germination--emerging mechanisms and new hypotheses  

PubMed Central

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

Nonogaki, Hiroyuki

2014-01-01

59

Gibberellin Biosynthesis and Response during Arabidopsis Seed Germination  

Microsoft Academic Search

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

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

2003-01-01

60

A shotgun phosphoproteomics analysis of embryos in germinated maize seeds  

Microsoft Academic Search

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

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

2008-01-01

61

G Protein Signaling in the Regulation of Arabidopsis Seed Germination  

NSDL National Science Digital Library

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

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

2005-11-01

62

Changes in RNA and Protein Metabolism Associated with Alterations in the Germination Efficiency of Sunflower Seeds  

Microsoft Academic Search

Precise knowledge of seed quality after harvest and during storage is of particular importance for seed producers. We analysed different sunflower seed lots (Helianthus annuusL.) characterized by extremes of germination ability. We used RNA analysis to study possible changes in gene expression in seeds unable to germinate. Total RNA content was very small in dry seeds showing a low germination

CHRISTOPHE REUZEAU; GÉRARD CAVALIÉ

1997-01-01

63

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

Microsoft Academic Search

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

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

2009-01-01

64

The influence of temperature, light, salinity and seed pre-treatment on the germination of Sesbania sesban seeds  

Microsoft Academic Search

The germination of Sesbania sesban seeds was studied under controlled environmental conditions. Interactive effects of temperature and light, effects of salinity and effects of different pre-treatments of seeds were studied. Sesbania seeds were placed in Petri dishes with filtration paper and the germination and radical development followed during seven day periods. The seeds generally germinated within one or two days.

Truong Hoang Dan; Hans Brix

65

Proteins induced by salt stress in tomato germinating seeds  

SciTech Connect

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

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

1989-04-01

66

Trace gas emissions and smoke-induced seed germination  

SciTech Connect

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

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

1997-05-23

67

Modelling the effects of water stress and temperature on germination rate of Orobanche aegyptiaca seeds  

Microsoft Academic Search

and in the field, water stress often limits germination (Benech-Arnold and Sanchez, 1995). At an optimum Orobanche aegyptiaca seeds were germinated at a temperature for germination with water and oxygen freely range of water potentials and temperatures and the available, the uptake of water by seeds has three phases progress of germination within the seed population (Ching, 1972). During the

E. Kebreab; A. J. Murdoch; Earley Gate

1999-01-01

68

PHYSIOLOGICAL EFFECTS OF DIFFERENT ENVIRONMENTAL CONDITIONS ON THE SEED GERMINATION OF RUMEX SCUTATUS L. (POLYGONACEAE)  

Microsoft Academic Search

Effects of temperature, time after harvest, light, pH and depth of soil on germination of Rumex scutatus L. (Polygonaceae) were investigated. The optimal for germination percent temperature for seeds was found to be at 25 0 C. Furthermore, the germination percentage increased with light. Seeds showed the greatest response germination in the alternating light \\/ dark regimes. The optimal seed

Dilek DEM?REZEN YILMAZ; Ahmet AKSOY

69

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

Microsoft Academic Search

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

Nilton Carlos Cáceres; Emygdio Leite de Araújo Monteiro-Filho

2007-01-01

70

The control of seed germination in Trollius ledebouri A model of seed dormancy  

Microsoft Academic Search

Treatment of Trollius ledebouri seeds with gibberellins A4+A7 promotes germination. The efficacy of the treatment is dependent upon the duration of imbibition in distilled water prior to GA4+7 application. ‘Presoaking’ increases both the final percentage germination attained and also its rate of achievement. No presoaking effect is exhibited by seeds induced to germinate by testa removal in the absence of

A. Hepher; J. A. Roberts

1985-01-01

71

Morphological Seed Traits and Germination of Six Species of Pachycereeae (Cactaceae)  

Microsoft Academic Search

Morphological seed traits and germination responses of freshly matured seeds of six species of Pachycereeae: Escontria chiotilla, Myrtillocactus geometrizans, Neobuxbaumia mezcalaensis, N. multiareolata, Pachycereus grandis, and Stenocereus queretaroensis were studied at room temperature in laboratory conditions with the hypothesis that seed size affects germination. Seeds are different in shape and testa structure. Both, number of seeds per fruit and seed

Sofía Loza-Cornejo; Lauro López-Mata; Teresa Terrazas

2008-01-01

72

Seed Production and Germinability of Cucurbit Crops  

Microsoft Academic Search

Cucurbit crops are mostly produced for their immature or mature fruits. However, a relatively high proportion of cucurbit fields are destined for seed production, either for seed consumption or for propagation material. Production of cucurbits for seed consumption (as a snack food) is very popular in some parts of the globe and almost unknown in others. Open-pollinated cultivars (inexpensive seeds)

Haim Nerson

73

Seed germination in response to diurnal fluctuations of temperature.  

PubMed

Diurnal fluctuations in temperature may initiate or accelerate germination in certain flowering plants, and the effectiveness of the stimulus varies according to the amplitude of fluctuation and the presence or absence of light. Attempts 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 investigation of germination responses to fluctuating temperatures, conducted on seeds of herbaceous species collected from native populations near Sheffield. The results suggest that requirements for diurnal fluctuations in temperature are characteristic of the germination of species from particular types of habitat and provide mechanisms which cause seeds to germinate at times and in places favourable for seedling establishment. PMID:16073423

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

1977-05-12

74

IAA production during germination of Orobanche spp. seeds  

Microsoft Academic Search

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

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

2004-01-01

75

Metabolism of carbohydrate and lipid reserves in germinated cotton seeds  

Microsoft Academic Search

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

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

1982-01-01

76

Expression of a Polygalacturonase Associated with Tomato Seed Germination1  

PubMed Central

Radicle protrusion from tomato (Lycopersicon esculentum Mill.) seeds to complete germination requires weakening of the endosperm tissue opposite the radicle tip. In common with other cell wall disassembly processes in plants, polygalacturonases (PGs) may be involved. Only calcium-dependent exo-PG activity was detected in tomato seed protein extracts. Chromatographic profiles of a partially acid-hydrolyzed fraction of polygalacturonic acid further digested with seed extract were consistent with the presence of only calcium-dependent exo-PG activity. In addition, a transcript encoding a previously unknown PG was detected prior to the completion of germination. The mRNA, produced from a gene (LeXPG1) estimated by Southern analysis to be represented once in the genome, was also present in flowers (anthers) and in lower amounts in roots and stems. LeXPG1 mRNA abundance was low during seed development, increased during imbibition, and was even greater in seeds that had completed germination. Expression of LeXPG1 during germination predominates in the endosperm cap and radicle tip, and in the radicle appears as a distinct band possibly associated with vascular tissue differentiation. We suggest that PG is involved in cell wall loosening of the endosperm necessary for radicle protrusion from tomato seeds and in subsequent embryo and seedling growth.

Sitrit, Yaron; Hadfield, Kristen A.; Bennett, Alan B.; Bradford, Kent J.; Downie, A. Bruce

1999-01-01

77

Protein changes during ethanol induced seed germination in Aconitum heterophyllum.  

PubMed

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

Rana, Bindu; Sreenivasulu, Yelam

2013-01-01

78

Gibberellic acid-mediated salt signaling in seed germination  

PubMed Central

Seed germination initiates the postembryonic development of plants, which determines successful seedling establishment and plant propagation. It is therefore tightly regulated by diverse environmental conditions, including high salinity and drought, as well as by intrinsic developmental programs, among which gibberellic acid (GA) is best understood. Regulatory roles of GA in seed germination have been extensively studied. It is also known that high salinity inhibits germination by repressing genes encoding GA biosynthetic enzymes. However, it is still unclear how salt signals are coordinately incorporated into the GA signaling pathway at the molecular level. We recently demonstrated that a membrane-bound NAC transcription factor, NTL8, mediates salt signaling, primarily through a RGL2-independent GA pathway, in regulating seed germination. High salinity promotes NTL8 transcription and proteolytic activation of NTL8. Notably, the NTL8-mediated salt signaling is independent of abscisic acid (ABA). These observations indicate that membrane-mediated transcription control is an important component of salt signaling during seed germination.

Kim, Sang-Gyu

2008-01-01

79

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

Microsoft Academic Search

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

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

2001-01-01

80

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

Microsoft Academic Search

Seeds vary widely in the sensitivity of germination to oxygen (O2) partial pressure, depending upon the species, temperature, dormancy state and physiological status of the seeds. Most analyses of the O2sensitivity of germination have focused on final germination percen- tages and estimated the O2 percentage in air that is required to reduce germination to a given percentage (usually 50%). In

Kent J. Bradford; Daniel Côme; Françoise Corbineau

2007-01-01

81

Homeopathically prepared gibberellic acid and barley seed germination.  

PubMed

The potentisation process by which homeopathic preparations are produced raises the concern that these medicines have placebo effects only, since they theoretically no longer contain active molecules of the diluted substance. Plant models offer a method of examining the efficacy of homeopathically prepared solutions. This study examined the effects of homeopathically prepared gibberellic acid (HGA3) on the germination performance of barley (Hordeum vulgare L.) seeds. The effect of HGA3 (4-200 cH) on seed germination rate and seedling development was compared to that of the most commonly used form of gibberellic acid (GA3), 0.5 g l(-1), and control (distilled water). The extent and type of response was dependent on the vigour level of the seedlot. Treating seeds from three vigour groups in HGA3 consistently resulted in larger seedlings. High-vigour seeds treated with HGA3 4, 30 and 200 cH germinated faster, and roots of medium-vigour seedlots treated in HGA3 15 cH were longer. Biphasic effects of HGA3 were also demonstrated. As a plant model, germinating barley seeds successfully demonstrated the ability of HGA3 to produce a biological response. PMID:12884896

Hamman, B; Koning, G; Lok, K Him

2003-07-01

82

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

Microsoft Academic Search

Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing\\u000a rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits\\u000a for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination\\u000a index, were investigated using one recombinant

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

2010-01-01

83

Production and Germination of Paper Birch Seed and its Dispersal into a Forest Opening.  

National Technical Information Service (NTIS)

A 3-year study of paper birch seed crops and seed dispersal showed that seed quality is important in evaluating a seed crop. Good seed represented 55 to 86 percent of the total seed production, and this seed had the better germination. Most of the seed wa...

J. C. Bjorkbom

1971-01-01

84

Seed germination and seedling growth of the Mexican sunflower Tithonia diversifolia (Compositae) in Nigeria, Africa  

Microsoft Academic Search

We studied seed germination and seedling growth of the Mexican sunflower Tithonia diversifolia in Nigeria. This involved the usage of some dormancy-releasing methods and the effect of some concentrations of three herbicide formulations on the young seedlings. Initial germination tests on fresh and stored seeds revealed a low percentage germination of less than 30%. The seeds of the weed exhibit

D. A. Agboola; W. F. Idowu; M. Kadiri

85

Apomictic embryo development and survival in Uapaca kirkiana under in vitro and in vivo seed germination  

Microsoft Academic Search

In vitro and in vivo studies on seed germination of Uapaca kirkiana were conducted at Bunda College of Agriculture. In vitro germination treatments included two fruit sources (market and direct from trees); seed coat (outer and inner layers) removal and two seed germination media (Murashige and Skoog (MS) and woody plant medium (WPM)). Incubation of in vitro cultures was under

M. F. A Maliro; M. B Kwapata

2000-01-01

86

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

Microsoft Academic Search

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

Anna Traveset

1998-01-01

87

ETHYLENE EVOLUTION AND ENDO-?-MANNANASE ACTIVITY DURING LETTUCE SEED GERMINATION AT HIGH TEMPERATURE  

Microsoft Academic Search

High temperatures during lettuce seed imbibition can delay or completely inhibit germination and the endosperm layer appears to restrict the radicle protrusion. The role of endo-?-mannanase during lettuce seed germination at 35 °C and the influence of ethylene in endo- ?-mannanase regulation were investigated. Seeds of 'Dark Green Boston' (DGB) and 'Everglades' (EVE) were germinated in water, or 10 mmol

Warley Marcos Nascimento; Daniel James Cantliffe; Donald John Huber

88

Arabidopsis nudix hydrolase 7 plays a role in seed germination.  

PubMed

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

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

2014-05-01

89

Dynamic histone acetylation of late embryonic genes during seed germination.  

PubMed

Histone acetylation is involved in the regulation of gene expression in plants and eukaryotes. Histone deacetylases (HDACs) are enzymes that catalyze the removal of acetyl groups from histones, which is associated with the repression of gene expression. To study the role of histone acetylation in the regulation of gene expression during seed germination, trichostatin A (TSA), a specific inhibitor of histone deacetylase, was used to treat imbibing Arabidopsis thaliana seeds. GeneChip arrays were used to show that TSA induces up-regulation of 45 genes and down-regulation of 27 genes during seed germination. Eight TSA-up-regulated genes were selected for further analysis - RAB18, RD29B, ATEM1, HSP70 and four late embryogenesis abundant protein genes (LEA). A gene expression time course shows that these eight genes are expressed at high levels in the dry seed and repressed upon seed imbibition at an exponential rate. In the presence of TSA, the onset of repression of the eight genes is not affected but the final level of repressed expression is elevated. Chromatin immunoprecipitation and HDAC assays show that there is a transient histone deacetylation event during seed germination at 1 day after imbibition, which serves as a key developmental signal that affects the repression of the eight genes. PMID:16307366

Tai, Helen H; Tai, George C C; Beardmore, Tannis

2005-12-01

90

Response of soybean seed germination to cadmium and acid rain.  

PubMed

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

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

2011-12-01

91

Sulfur dioxide effects on petunia pollen germination and seed set  

SciTech Connect

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

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

1985-05-01

92

[Virus infestation of garden radish (Raphanus sativus L. var. sativus) (author's transl)].  

PubMed

In July 1974 a mosaic disease was stated in seed plants of garden radish near Aschersleben which spread more and more within some weeks and eventually infected over 40 per cent of the stand. Investigations in comparison with healthy seed plants demonstrated the following average losses induced by the disease: number of pods 51 per cent, seed weight 67 per cent, number of seeds per plant 53 per cent, weight of 1,000 seeds 33 per cent. Nearly unaffected were: number of seeds per pod, percentage of seed germination, and percentage of emerged seedlings. However, the seedlings were smaller when they derived from diseased mother plants. From diseased seed plants cauliflower mosaic virus was isolated. Seed transmission of this virus could not be stated with several hundreds of seedlings deriving from diseased garden radish. Back transmissions were successful with sap and with aphids. Only one strain which was cultivated in greenhouse for a long time gave no positive results. Three isolates of cabbage black ring virus from different plant species and the four beetle-transmissible viruses, namely turnip yellow mosaic, turnip crinkle, turnip rosette, and radish mosaic viruses induced no symptoms on garden radish seedlings. However, Erysimum latent virus, also belonging to the beetle-transmissible viruses, sometimes caused symptoms in garden radish. For the first time the investigations demonstrated in Europe, but probably also for the other continents, a spontaneous virus infection of Raphanus sativus var. sativus. PMID:1037175

Schmelzer, K

1976-01-01

93

Germination of vegetable seeds exposed to very high pressure  

NASA Astrophysics Data System (ADS)

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

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

2012-07-01

94

Fruit harvesting time and corresponding morphological changes of seed integuments influence in vitro seed germination of Dendrobium nobile Lindl  

Microsoft Academic Search

In vitro asymbiotic seed germination of Dendrobium nobile varied significantly with fruit harvesting time and growth medium used for culturing seeds. Seeds harvested 129 days after\\u000a pollination (DAP) possessing globular shaped embryos and a discontinuous cuticle layer showed a substantially greater germination\\u000a on P668 medium. Alternatively, immature seeds harvested 96 and 116 DAP displayed a significantly lower germination response\\u000a on various

Rajeswari Vasudevan; Johannes van Staden

2010-01-01

95

Return to Our Roots: Raising Radishes to Teach Experimental Design. Methods and Techniques.  

ERIC Educational Resources Information Center

Reviews research in teaching applied statistics. Concludes that students should analyze data from studies they have designed and conducted. Describes an activity in which students study germination and growth of radish seeds. Includes a table providing student instructions for both the experimental procedure and data analysis. (CFR)

Stallings, William M.

1993-01-01

96

Effect of day length on germination of seeds collected in Alaska  

USGS Publications Warehouse

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.

Densmore, R. V.

1997-01-01

97

Germination capability of immature seeds of Lotus ornithopodioides L. and Scorpiurus subvillosus L  

Microsoft Academic Search

SUMMARY - Lotus ornithopodioides L. and Scorpiurus subvillosus L. are two hard seed pasture legumes that are very palatable to livestock. In order to overcome the obstacle of hard seed, immature seeds of these species were collected from mother plants and stored at 5°C until the beginning of the germination trial. Seed germination was evaluated at 7 different temperatures of

A. Cristaudo; F. Gresta; G. Avola; V. Miano

98

Comparison of seed germination techniques for common elderberry (Sambucus nigra L. ssp. canadensis)  

Microsoft Academic Search

Soaking common elderberry seeds (Sambucus nigra L. ssp. canadensis (L.) R. Bolli [Caprifoliaceae]) in sulfuric acid followed by a 60-d stratification, or subjecting common elderberry seeds to a 60-d warm, moist treatment followed by a 90-d stratification, significantly increased seed germination of accession 9084126 common elderberry seeds. Stratification alone was less effective in promoting germination than was acid scarification followed

John W Leif; John C Durling; David W Burgdorf

2011-01-01

99

Comparison of seed germination techniques for common elderberry (Sambucus nigra L. ssp. canadensis)  

Microsoft Academic Search

: Soaking common elderberry seeds (Sambucus nigra L. ssp. canadensis (L.) R. Bolli [Caprifoliaceae]) in sulfuric acid followed by a 60-d stratification, or subjecting common elderberry seeds to a 60-d warm, moist treatment followed by a 90-d stratification, significantly increased seed germination of accession 9084126 common elderberry seeds. Stratification alone was less effective in promoting germination than was acid scarification

John W Leif; John C Durling; David W Burgdorf

2011-01-01

100

Seed germination of a newly discovered hyperaccumulator Solanum nigrum L. affected by illumination and seed-soaking reagent.  

PubMed

Solanum nigrum is a newly found Cd-hyperaccumulator which showed very high remediation efficiency in polluted soil. Seed germination experiments with different illumination and seed-soaking reagents were conducted in constant temperature box and greenhouse with soil as burgeon base. The results showed that the germination rate with alternating light/dark photoperiod was about twice of that without lighting (p < 0.05), suggesting that illumination is one of the important conditions for seed germination of S. nigrum. All treatments with seed-soaking reagents significantly increased the seed germination rate of S. nigrum (p < 0.05). Treatment with H2O2 (0.1%) had the shortest germination time. The germination rate of seeds that were not washed in water following soaking was 2-3 times higher than that of seeds that were washed after soaking. PMID:19497664

Wei, Shuhe; Hu, Yahu; Srivastava, Mrittunjai; Zhou, Qixing; Niu, Rongcheng; Li, Yunmeng; Wu, Zhijie; Sun, Tieheng

2009-10-30

101

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

PubMed

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

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

2008-01-01

102

Effects of Seed Cryopreservation and Priming on Germination in Several Cultivars of Apium graveolens  

PubMed Central

Seed germination of seven celery cultivars was studied after storage in liquid nitrogen for 1 or 30 d. Cryopreservation was also carried out on pelleted and primed seeds. None of the treatments applied reduced germination percentages. T50 (time for germination to reach 50%) significantly decreased in Florida, Utah and Istar cultivars when priming, alone or in combination with cryopreservation, was used.

Gonzalez-Benito, M. E.; Iriondo, J. M.; Pita, J. M.; Perez-Garcia, F.

1995-01-01

103

Differentiation in seed germination among populations of Capsicum annuum along a latitudinal gradient in Mexico  

Microsoft Academic Search

Toinvestigate variation in germination capability of wild Capsicumannuum seeds, the effects of light, fluctuating temperature,gibberellic acid (GA), soaking and sulfuric acid were analyzed in samples from14 populations from northwest Mexico. Germination was inhibited by darkness inall populations studied. Darkness inhibition of germination was overcome byfluctuating temperature and GA, factors which also increased germinationpercentage but not germination rate. Soaking treatments did

Sergio Hernández-Verdugo; Ken Oyama; Carlos Vázquez-Yanes

2001-01-01

104

Effect of scarification, GA and chilling on the germination of goldenrain-tree ( Koelreuteria paniculata Laxm.) seeds  

Microsoft Academic Search

In contrast to scarified seeds, unscarified seed did not germinate in any of the treatments, indicating that Koelreuteria paniculata Laxm. seeds have hard, impermeable seed coat dormancy. Exogenous application of 100, 200 and 300ppm GA increased germination of scarified seeds from 0 (control) to 17, 18 and 15%, respectively. Pre-chilling in distilled water (DW) for 60 days increased germination to

S Rehman; In-Hwan Park

2000-01-01

105

A simple staining method for observation of germinated Striga seeds  

Microsoft Academic Search

In vitro techniques are essential for Striga research and the development of appropriate control methods. In the laboratory, pre-screening of non-host or false-host plants of Striga for trap cropping or the screening of hosts for resistance involves visual evaluation of Striga seed germination that may be stimulated by plant parts or root exudates. This technique is presently laborious because the

Shusheng Long; Venasius Lendzemo; Thomas W. Kuyper; Zhengsheng Kang; Horst Vierheilig; Siegrid Steinkellner

2008-01-01

106

Response of Soybean Seed Germination to Cadmium and Acid Rain  

Microsoft Academic Search

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

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

107

Dynamic Histone Acetylation of Late Embryonic Genes during Seed Germination  

Microsoft Academic Search

Histone acetylation is involved in the regulation of gene expression in plants and eukaryotes. Histone deacetylases (HDACs)\\u000a are enzymes that catalyze the removal of acetyl groups from histones, which is associated with the repression of gene expression.\\u000a To study the role of histone acetylation in the regulation of gene expression during seed germination, trichostatin A (TSA),\\u000a a specific inhibitor of

Helen H. Tai; George C. C. Tai; Tannis Beardmore

2005-01-01

108

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

PubMed

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

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

2005-10-01

109

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

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.

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

2006-01-01

110

Germination dramatically increases isoflavonoid content and diversity in chickpea (Cicer arietinum L.) seeds.  

PubMed

The effect of germination on bioactive components in legume seeds was investigated in terms of the antioxidant capacity and total phenolic contents. Germination increased the total phenolic content and antioxidant capacity of most seeds. Particularly in chickpea seeds, the isoflavone contents increased by over 100 fold, mainly due to the increase of formononetin and biochanin A level. As a result, these two compounds were conveniently isolated from the germinated seeds in preparative scale and structurally confirmed by UV-vis, ESI-MS, and (1)H NMR spectroscopies. Isoflavonoid fingerprints analyzed by HPLC-PDA and LC-ESI-MS demonstrated that germination could significantly increase isoflavonoids diversity. Twenty-five isoflavonoids were detected and identified tentatively. These include 20 isoflavones, 2 isoflavanones, and 3 pterocarpan phytoalexins. Total isoflavonoid content of germinated chickpea was approximately 5-fold of that of germinated soybean. Our findings suggest that the germinated chickpea seeds could serve as a promising functional food rich in isoflavonoids. PMID:22816801

Wu, Ziyun; Song, Lixia; Feng, Shengbao; Liu, Yuancai; He, Guangyuan; Yioe, Yoecelyn; Liu, Shao Quan; Huang, Dejian

2012-09-01

111

[Characteristics of seed germination of rare plant species Reaumuria trigyna in west Ordos].  

PubMed

Reaumuria trigyna is a relic species in the desert shrubbery vegetation in arid regions of northwestern China, and plays an important role in the maintenance of the stability of desert vegetation. In this paper, the seed traits and germination strategy of R. trigyna under different environmental conditions, e.g., light, temperature, soil moisture, and sand bury, were investigated. The results showed that R. trigyna seed had high vigor and high germination rate, and endured reserve. The seed could germinate either in light or in darkness, and the optimal temperature for germination was 20 degrees C - 25 degrees C or 15 degrees C/25 degrees C, with the germination rate being 93%. The seed could start to germinate when soil moisture content was 2%, and the germination rate was the highest (89%) when the moisture content was 12%. The optimal sand burial depth of R. trigyna seed was 1 cm, and no seed would germinate when the sand burial depth was >5 cm. Sand burial depth had significant effects on the seedling's emergence percentage and growth height, but lesser effects on seedling' s mass. Soil moisture and sand burial depth were the main environmental factors limiting the seed germination and seedling emergence of R. trigyna. The high seed germination rate of R. trigyna enhanced the survival risk of its seedlings, which was unfavorable to its handling with the extreme changes of desert environment. Such a character of R. trigyna seed was one of the factors causing the species endangered. PMID:19288705

Zhang, Ying-juan; Wang, Yu-shan; Li, Qing-feng

2008-12-01

112

Proteomic analysis of oil mobilization in seed germination and postgermination development of Jatropha curcas.  

PubMed

To understand oil mobilization in germinating seeds, we performed ultrastructural observation and proteomic analysis of endosperm in germinating Jatropha curcas seeds. Results showed that the oil mobilization was initiated during germination, and then the oil was consumed for early seedling development. The significant change in abundance of 50 protein spots during germination indicated that several pathways including beta-oxidation, glyoxylate cycle, glycolysis, citric acid cycle, gluconeogenesis, and pentose phosphate pathway were involved in the oil mobilization. PMID:19152324

Yang, Ming-Feng; Liu, Yu-Jun; Liu, Yun; Chen, Hui; Chen, Fan; Shen, Shi-Hua

2009-03-01

113

Physiological ecology of seed germination for the columnar cactus Stenocereus queretaroensis  

Microsoft Academic Search

Responses of seed germination to temperature, water potential, time after harvest, and light were investigated for Stenocereus queretaroensis, a columnar cactus native to west central Mexico. Germination was optimal between 20°C and 30°C, and the germination percentage decreased as the water potential was lowered from 0·00 to ?1·0 MPa. Maximal germination of 85% occurred for seeds that were 11 –

Erick De la Barrera; Park S. Nobel

2003-01-01

114

Teaching Through Trade Books: Secrets of Seeds  

NSDL National Science Digital Library

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

Morgan, Emily; Ansberry, Karen

2009-02-01

115

Polyamines and related enzymes in rice seeds differing in germination potential  

Microsoft Academic Search

In ungerminated rice seeds, (Japonica rice variety, CV Tapei 309), the content of free amines (putrescine, spermidine, spermine, tyramine) was higher in seed lots having a low germination frequency compared to those with high germination potential. Conversely, amine conjugates (di-feruloylputrescine, di-feruloylspermidine, diferuloyldiaminopropane and feruloyltyramine) decreased with loss of viability. Thus, these compounds appeared to constitute biochemical markers of seed viability.

L. Bonneau; M. Carré; J. Martin-Tanguy

1994-01-01

116

Interactive effects of GAs, CKs and growth retardants on the germination of celery seeds  

Microsoft Academic Search

The germination of whole seeds of celery (Apium graveolens L.) was inhibited by paclobutrazol, ancymidol and lower concentrations of uniconazole. The growth retardants daminozide, AMO 1618 and chlormequat chloride inhibited the germination of cut seeds only, indicating that the seed coat prevents the penetration of these compounds at the examined concentrations. Application of a mixture of the gibberellins A4 and

E. Pressman; R. Shaked

1991-01-01

117

Thermal and hormonal regulation of the dormancy-germination transition in Amaranthus tuberculatus seeds  

Microsoft Academic Search

Summary The transition from seed dormancy to germination is a multi-step process. However, distinguishing between physiological processes involved in seed dormancy alleviation and those involved in germination has been difficult. We studied the seed dormancy alleviation process in Amaranthus tuberculatus, an important weed species in midwestern USA. Using three A. tuberculatus biotypes that differ in dormancy level, it was determined

RGL EON; MDKO WEN

2007-01-01

118

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

Microsoft Academic Search

Dormancy release in imbibed annual ryegrass (Lolium rigidum Gaud.) seeds is promoted in the dark but inhibited in the light. The role of abscisic acid (ABA) in inhibition of dormancy release was found to be negligible, compared with its subsequent effect on germination of dormant and non-dormant seeds. Inhibitors of ABA metabolism had the expected effects on seed germination but

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

2009-01-01

119

Effect of seed collection times and pretreatment methods on germination of Terminalia sericea Burch. ex DC  

Microsoft Academic Search

A nursery experiment was conducted to study the effects of seed collection times and pretreatment methods on the germination of Terminalia sericea Burch. ex DC. (Combretaceae). T. sericea is a multipurpose tree species occurring in the miombo woodlands whose seedling production is hampered by very low seed germination rate. Seeds were subjected to four treatment methods each at four different

Michael G. Likoswe; Joyce P. Njoloma; Weston F. Mwase; Clement Z. Chilima

120

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

Microsoft Academic Search

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

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

121

Pre-Sowing Treatments to Improve Seed Germination in Angelica glauca Edgew, an Endangered Medicinal Herb of the Western Himalayas  

Microsoft Academic Search

Angelica glauca (Apiaceae), endemic to the Himalaya, is an endangered medicinal herb for which, beside in situ conservation, ex situ cultivation is recommended to overcome poor seed germination that limits natural reproduction in the species. To determine the germination potential of the species, the germination of seeds collected from several populations were measured. Germination in seeds treated with KNO3 and

Rajiv K. Vashistha; B. P. Nautiyal; M. C. Nautiyal

2009-01-01

122

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

NASA Astrophysics Data System (ADS)

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

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

2010-06-01

123

Factors and mechanisms influencing seed germination in a wetland plant sawgrass  

Microsoft Academic Search

Sawgrass (Cladium jamaicense) is the predominant plant and vegetation community in the Florida Everglades. Germination of sawgrass seeds in the laboratory\\u000a or nursery has been difficult and problematic, yet little is known about the physiological mechanistic regulation of the sawgrass\\u000a seed germination process. In the present study, we examined the factors and mechanisms that influence sawgrass seed germination.\\u000a We found

James Webb; ShiLi Miao; Xing-Hai Zhang

2009-01-01

124

Carbamoyl Phosphate Synthetase Activity from the Cotyledons of Developing and Germinating Pea Seeds  

PubMed Central

Carbamoyl phosphate synthetase activity was measured in partially purified extracts from cotyledons of developing and germinating seeds of Pisum sativum L. Some properties of the enzyme were established. During cotyledon development, the activity initially increased sharply but decreased during further development. The activity from germinating seeds was only one-tenth of the maximum activity at an early developmental phase. The results are discussed in relation to pea seed development and germination.

Kolloffel, Chris; Verkerk, Bep C.

1982-01-01

125

Effects of Neotyphodium Fungi on Lolium multiflorum Seed Germination in Relation to Water Availability  

PubMed Central

• Background and Aims Temperate endophyte-infected (Neotyphodium sp.) grasses have been shown to exhibit an ecological advantage over endophyte-uninfected grasses under abiotic stressful conditions. It is predicted that endophyte-infected plant populations will display higher rates of germination and proportion of germinated seeds under limiting water conditions. • Methods The hydrotime regression model was used to describe the effect of Neotyphodium endophyte on seed germination of Lolium multiflorum at different water potentials. Additionally, seed mortality after water stress exposure was estimated in endophyte-infected and -uninfected seeds. • Key Results Endophyte infection inhibited seed germination at all water potentials. The hydrotime model described satisfactorily the germination responses, and revealed that endophyte-free seeds exhibited higher rates of and final percentage germination, probably due to a lower base water potential compared with endophyte-infected seeds. However, Neotyphodium endophyte conferred a higher rate of survival in those seeds that remained ungerminated when exposed to highly water stress conditions. • Conclusions Changes produced by Neotyphodium endophyte in L. multiflorum seeds might affect fitness in particular ecological scenarios. For example, the presence of the endophyte may curtail seed germination when water is limiting, reducing the risk of seedling death. Conversely, endophyte-free seeds would display an enhanced germination, ensuring a more rapid seedling establishment if later water conditions do not restrict plant growth.

GUNDEL, P. E.; MASEDA, P. H.; VILA-AIUB, M. M.; GHERSA, C. M.; BENECH-ARNOLD, R.

2006-01-01

126

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

Microsoft Academic Search

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

Sachiko Araki; Izumi Washitani

2000-01-01

127

Acid phosphatase activities during the germination of Glycine max seeds.  

PubMed

In this paper, we describe a study concerning the determination of some characteristics of soybean seedlings and the detection of acid phosphatase activities towards different substrates during the germination. Enzyme activities with p-nitrophenylphosphate (pNPP) and inorganic pyrophosphate (PPi) as substrates were detected from the 5th and 7th days after germination, respectively. Acid phosphatase activities with tyrosine phosphate (TyrP), glucose-6-phosphate (G6P) and phosphoenol pyruvate (PEP) were also observed but to a lesser extent. Under the same conditions, no enzyme activity was detected with phytic acid (PhyAc) as substrate. The appearance of phosphatase activity was coincident with the decrease of inorganic phosphate content during germination; over the same period, the protein content increased up to the 5th day, decreased until the 8th day, and remained constant after this period. Relative to phosphatase activity in the cotyledons, the activities detected in the hypocotyl and roots were 82% and 38%, respectively. During storage the enzyme maintained about 63% of its activity for 3 months at 5 degrees C. The specificity constant (Vmax/Km) values for pNPP and PPi were 212 and 64 mu kat mM-1 mg-1, respectively. Amongst the substrates tested, PPi could be a potential physiological substrate for acid phosphatase during the germination of soybean seeds. PMID:15061079

dos Prazeres, Janaina Nicanuzia; Ferreira, Carmen Veríssima; Aoyama, Hiroshi

2004-01-01

128

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

Microsoft Academic Search

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

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

2002-01-01

129

?? ????????????? ?????? ???????????????????????????? ?????????????????????????? Number of Seeds in a Fruit, Germination and Effect of Desiccation on Seed Storage in Amoora polystachya ?????? ?????????1  

Microsoft Academic Search

The study on relationship between number of seeds in a fruit and germination and the effect of desiccation on seed storage of Amoora polystachya was conducted at the Silviculture Research Centre 5, Kamphaeng Phet province during March 1998 to July 1999 using seed samples from Kamphaeng Phet and Tak. The study concentrated on effect of number of seed in a

Bundit Ponoy; Prapai Khaennak; Sompong Paktoop

130

Seed Germination of GA-Insensitive sleepy1 Mutants Does Not Require RGL2 Protein Disappearance in Arabidopsis[W  

PubMed Central

We explore the roles of gibberellin (GA) signaling genes SLEEPY1 (SLY1) and RGA-LIKE2 (RGL2) in regulation of seed germination in Arabidopsis thaliana, a plant in which the hormone GA is required for seed germination. Seed germination failure in the GA biosynthesis mutant ga1-3 is rescued by GA and by mutations in the DELLA gene RGL2, suggesting that RGL2 represses seed germination. RGL2 protein disappears before wild-type seed germination, consistent with the model that GA stimulates germination by causing the SCFSLY1 E3 ubiquitin ligase complex to trigger ubiquitination and destruction of RGL2. Unlike ga1-3, the GA-insensitive sly1 mutants show variable seed dormancy. Seed lots with high seed dormancy after-ripened slowly, with stronger alleles requiring more time. We expected that if RGL2 negatively controls seed germination, sly1 mutant seeds that germinate well should accumulate lower RGL2 levels than those failing to germinate. Surprisingly, RGL2 accumulated at high levels even in after-ripened sly1 mutant seeds with 100% germination, suggesting that RGL2 disappearance is not a prerequisite for seed germination in the sly1 background. Without GA, several GA-induced genes show increased accumulation in sly1 seeds compared with ga1-3. It is possible that the RGL2 repressor of seed germination is inactivated by after-ripening of sly1 mutant seeds.

Ariizumi, Tohru; Steber, Camille M.

2007-01-01

131

G Protein Signaling in the Regulation of Rice Seed Germination  

NSDL National Science Digital Library

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

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

2005-11-15

132

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

PubMed Central

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.

Kahmen, S.; Poschlod, P.

2008-01-01

133

Interaction Effects of Seed Mass and Temperature on Germination in Australian Species of Frankenia (Frankeniaceae)  

Microsoft Academic Search

The seed size and number theories have been proposed to explain the advantages of having many small versus a few large seeds\\u000a in plants. In particular, seed germination is predicted to be shaped by temperature, and may differ for small and large seeds.\\u000a In this study, we experimentally test germination at different temperatures in 12 species of arid zone plants

Lyndlee C. Easton; Sonia Kleindorfer

2008-01-01

134

Field fate of Amaranthus patulus seeds subjected to leaf-canopy inhibition of germination  

Microsoft Academic Search

The germination of seeds of Amaranthus patulus Bertol., is known to be sensitive to leaf-transmitted light. Seeds were enclosed in transparent polyester-mesh envelopes and placed horizontally in 10-cm deep soil or on the soil surface, beneath a closed vegetation cover in the field. Changes in the numbers of firm intact seeds and of germinable seeds were traced for up to

Izumi Washitani

1985-01-01

135

Production of Strigolactones by Arabidopsis thaliana responsible for Orobanche aegyptiaca seed germination  

Microsoft Academic Search

The germination stimulants produced by Arabidopsis thaliana, a host of root parasitic plants Orobanche spp. but not of arbuscular mycorrhizal (AM) fungi were examined. Root exudates from the hydroponically grown A. thaliana plants were subjected to reverse phase high performance liquid chromatography (HPLC) and retention times of germination stimulants\\u000a inducing O. aegyptiaca seed germination were compared with those of strigolactone

Yaakov Goldwasser; Kaori Yoneyama; Xiaonan Xie; Koichi Yoneyama

2008-01-01

136

Germination of coffee seeds and its significance for coffee quality.  

PubMed

Besides genotypic characteristics, the crucial factor that determines coffee quality is the mode of post-harvest treatment, i.e., the wet and dry processing. Up to now, the resulting characteristic flavour differences between these differentially processed coffees were attributed exclusively to differences in starting material. However, as these quality differences are still evident, even when identical coffee samples were processed by the two methods in parallel, the differences must be created by metabolic processes in the coffee beans themselves. Based on expression studies of the germination-specific isocitrate lyase and the resumption of cell cycle activity, monitored by the abundance of beta-tubulin, we evidence that germination is initiated in coffee seeds during the course of standard coffee post-harvest treatments. The extent and nature of the germination processes depend on the processing method. The coherence of metabolic events, substantial differences in the chemical composition of the coffee beans, and the generation of specific coffee qualities establishes the basis for a quite novel approach in coffee research. PMID:16547871

Selmar, D; Bytof, G; Knopp, S-E; Breitenstein, B

2006-03-01

137

[Effect of seed soaking with aluminum on seed germination and seedling physiology of Platycodon grandiflorum].  

PubMed

In order to study the effect of seed soaking with different aluminum solution on seed germination and seedling physiological characteristics of Platycondon grandiflorum, two P. grandiflorum varieties'seed (the white flower and the purple flower) were soaked in Al3+ solution with different concentrations (0, 10, 100, 250, 500, 750 and 1000 mg x L) for 24 h, then germinated in illumination incubator. Results showed that the aluminum toxicity on the trends of the germination rate, germination index and vigor index was positive associated with its concentration, and the Al tolerance of the purple was slightly greater than that of the white. There were some relationships between the physiological indices, which were the leakage rate of electrolyte, the malonaldehyde (MDA) content, the activities of peroxidase (POD) and superoxide dismutase (SOD) , the free praline(Pro) and the soluble sugar contents, with the concentrations of Al. It was suggested that there was Al tolerance difference between the two P. grandiflorum varieties: the purple flower was greater than the white. PMID:21438384

Zhu, Lixiang; Wang, Jianhua; Fang, Xinsheng; Wang, Yong; Hao, Junkai; Weiwei, Ma; Jiao, Tianying

2010-12-01

138

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

PubMed Central

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.

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

2007-01-01

139

Soil Texture Involvement in Germination and Emergence of Buried Weed Seeds  

Microsoft Academic Search

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

Stefano Benvenuti

2003-01-01

140

LIPID COMPOSITION IN FAST AND SLOW GERMINATING SUNFLOWER (HELIANTHUS ANNUUS L.) SEEDS  

Microsoft Academic Search

Summary. The physiochemical characteristics and lipid composition in fast and slow germinating sunflower ( Helianthus annuus L.) seeds were studied. The quantity of phospholipids, glycolipids and sterols in cotyledons and embryonic axes in fast germinating seeds (FG - embryo emerged within 24 h after sowing) increased progressively between the 1st - 6th days after sowing (DAS) compared with the slow

S. K. Munshi; S. Sandhu; S. Sharma

141

Effect of heavy metals on germination of seeds.  

PubMed

With the expansion of the world population, the environmental pollution and toxicity by chemicals raises concern. Rapid industrialization and urbanization processes has led to the incorporation of pollutants such as pesticides, petroleum products, acids and heavy metals in the natural resources like soil, water and air thus degrading not only the quality of the environment, but also affecting both plants and animals. Heavy metals including lead, nickel, cadmium, copper, cobalt, chromium and mercury are important environmental pollutants that cause toxic effects to plants; thus, lessening productivity and posing dangerous threats to the agro-ecosystems. They act as stress to plants and affect the plant physiology. In this review, we have summarized the effects of heavy metals on seeds of different plants affecting the germination process. Although reports exist on mechanisms by which the heavy metals act as stress and how plants have learnt to overcome, the future scope of this review remains in excavating the signaling mechanisms in germinating seeds in response to heavy metal stress. PMID:24082715

Sethy, Sunil Kumar; Ghosh, Shyamasree

2013-07-01

142

Effects of brassinosteroids on conditioning and germination of clover broomrape (Orobanche minor) seeds  

Microsoft Academic Search

Brassinolide [2a, 3a, 22R,23R-tetrahydroxy-24S-methyl-B-homo-7-oxa-5-a-cholestan-6-one] and its related compounds, brassinosteroids, applied at the early stages of conditioning shortened the conditioning period required before clover broomrape seeds would germinate after exposure to germination stimulants, such as dl-strigol and natural stimulants from red clover (Trifolium pratense L.) root exudate. Brassinosteroids applied after conditioning increased the rate of the seed germination induced by these

Yasutomo Takeuchi; Yumi Omigawa; Masaru Ogasawara; Koichi Yoneyama; Makoto Konnai; A. Douglas Worsham

1995-01-01

143

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

NASA Astrophysics Data System (ADS)

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

Pineda-Mejia, Renan

144

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

Microsoft Academic Search

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

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

2002-01-01

145

Germinable soil seed banks in a tropical savanna: seasonal dynamics and effects of fire  

Microsoft Academic Search

The germinable soil seed bank of a tropical eucalypt savanna of north-eastern Australia was found to be dominated by grasses and forbs, with seed bank density ranging from 58 to 792 seeds per square metre, from a total of 53 species. Late dry season fires and the fire-related cues, heat shock and smoke, broke the seed dormancy of a range

Paul R. Williams; Robert A. Congdon; Anthony C. Grice; Peter J. Clarke

2005-01-01

146

Drying Rates following Priming Affect Temperature Sensitivity of Germination and Longevity of Lettuce Seeds  

Microsoft Academic Search

Seed priming (controlled hydration followed by drying) is used to alleviate high temperature inhibition of germination and improve seedling emergence of lettuce (Lactuca sativa L.) and other species. However, seed priming can also reduce the longevity of seeds during dry storage. Alternative drying methods (i.e., slow drying or moisture content re- duction (MCR) before drying) can extend seed longevity compared

Andrés R. Schwember; Kent J. Bradford

147

Effect of high temperature on moisture loss, imbibition and germination in the seeds of Trianthema Crystallina Vahl. and its distribution  

Microsoft Academic Search

Summary The germination behaviour of the seeds ofT. crystallina in relation to its frequent distribution in arid and semi-arid belt of Rajasthan has been investigated. In nature, the seed germination in this weed is definitely effected and to some extent controlled by certain features like light, environmental temperature fluctuations, germination temperature and seed age, and their complex effect seems to

M. C. Joshi; B. C. Nigam

1973-01-01

148

cGMP is required for seed germination in Arabidopsis thaliana.  

PubMed

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

Teng, Yao; Xu, Wenzhong; Ma, Mi

2010-07-15

149

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

PubMed

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

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

2005-01-01

150

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

PubMed

Ecological restoration of disturbed areas requires substantial knowledge of the germination of native plants and the creation of novel methods to increase seedling establishment in the field. We studied the effects of soil matrix priming on the germination of Dodonaea viscosa seeds, which exhibit physical dormancy. To this end, we buried both pre-scarified (in H2 SO4 , 3 min) and non-pre-scarified seeds in the Parque Ecológico de la Ciudad de México. After seeds were unearthed, they were post-scarified for 0, 2, 6 and 10 min and their germination percentages compared to the germination of a control batch of laboratory-stored seeds. For both control and unearthed seeds, the protein pattern was determined in the enriched storage protein fraction in SDS-PAGE gels stained with Coomassie blue. Percentage germination increased as the scarification time increased. Pre-scarification significantly increased percentage germination of post-scarified seeds in relation to the control and non-pre-scarified seeds. In seeds unearthed from the forest site, the buried pre-scarified seeds had relatively high percentage germination, even in the absence of post-scarification treatment. A 48-kDa protein was not found in unearthed, pre-scarified seeds nor in the control germinated seeds, indicating that mobilisation of this protein occurred during soil priming. Burying seeds for a short period, including the beginning of the rainy season, promoted natural priming, which increased protein mobilisation. Functionally, priming effects were reflected in high percentage seedling survival in both the shade house and the field. Seed burial also reduced the requirement for acidic post-scarification. PMID:24148161

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

2014-07-01

151

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

PubMed Central

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

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

2008-01-01

152

Arabidopsis seed development and germination is associated with temporally distinct metabolic switches.  

PubMed

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

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

2006-11-01

153

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

PubMed Central

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.

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

2006-01-01

154

Phytochrome regulates gibberellin biosynthesis during germination of photoblastic lettuce seeds.  

PubMed

Germination of lettuce (Lactuca sativa L.) seed is regulated by phytochrome. The requirement for red light is circumvented by the application of gibberellin (GA). We have previously shown that the endogenous content of GA1, the main bioactive GA in lettuce seeds, increases after red-light treatment. To clarify which step of GA1 synthesis is regulated by phytochrome, cDNAs encoding GA 20-oxidases (Ls20ox1 and Ls20ox2, for L. sativa GA 20-oxidase) and 3beta-hydroxylases (Ls3h1 and Ls3h2 for L. sativa GA 3beta-hydroxylase) were isolated from lettuce seeds by reverse-transcription polymerase chain reaction. Functional analysis of recombinant proteins expressed in Escherichia coli confirmed that the Ls20ox and Ls3h encode GA 20-oxidases and 3beta-hydroxylases, respectively. Northern-blot analysis showed that Ls3h1 expression was dramatically induced by red-light treatment within 2 h, and that this effect was canceled by a subsequent far-red-light treatment. Ls3h2 mRNA was not detected in seeds that had been allowed to imbibe under any light conditions. Expression of the two Ls20ox genes was induced by initial imbibition alone in the dark. The level of Ls20ox2 mRNA decreased after the red-light treatment, whereas that of Ls20ox1 was unaffected by light. These results suggest that red light promotes GA1 synthesis in lettuce seeds by inducing Ls3h1 expression via phytochrome action. PMID:9847128

Toyomasu, T; Kawaide, H; Mitsuhashi, W; Inoue, Y; Kamiya, Y

1998-12-01

155

Heterogeneity of Catalase in Maturing and Germinated Cotton Seeds 1  

PubMed Central

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

Kunce, Christine M.; Trelease, Richard N.

1986-01-01

156

The role of avian frugivores in germination of seeds of fleshy-fruited invasive alien plants  

Microsoft Academic Search

Many highly invasive plant species have fleshy fruits which are eaten by native frugivorous animals. These frugivores play\\u000a an important role in long-distance seed dispersal, and may also affect germination success. The aim of this study was to determine\\u000a whether generalist frugivores enhance or decrease seed germination of invasive alien species through pulp removal or seed\\u000a coat abrasion, besides serving

Lorinda A. Jordaan; Steven D. Johnson; Colleen T. Downs

2011-01-01

157

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

Microsoft Academic Search

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

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

1987-01-01

158

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

Microsoft Academic Search

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

Sharon ReidJuan; Juan J. Armesto

2011-01-01

159

ACC conversion to ethylene by sunflower seeds in relation to maturation, germination and thermodormancy  

Microsoft Academic Search

Conversion of exogenous 1-aminocyclopropane-1-carboxylic acid (ACC) to ethylene was studied in sunflower (Helianthus annuus L., cv. Mirasol) seeds in relation to germinability. Ethylene production from ACC decreased during seed maturation, and non-dormant mature seeds were practically unable to synthesize ethylene until germination and growth occurred, indicating that ethylene forming enzyme (EFE) activity developed during tissue imbibition and growth. ACC conversion

F. Corbineau; R. M. Rudnicki; D. Côme

1989-01-01

160

The influence of sunflower and mustard leaf extracts on the germination of mustard seeds  

Microsoft Academic Search

The extracts from sunflower and mustard leaves were separated using SPE-Columns. The mustard seeds were germinated on water\\u000a (24 h) and subsequently on crude extracts or separate fractions. The heat production rate was measured by isothermal calorimetry\\u000a at 21°C and changes in seed cotyledons by FT-Raman spectroscopy. Crude extracts strongly inhibited seed germination. The water\\u000a and ‘methanol’ fractions of mustard

Magdalena Tro?; A. Skoczowski; Ma?gorzata Bara?ska

2009-01-01

161

A COMPUTER-CONTROLLED SEED GERMINATOR FOR REALISTIC TEMPERATURE RESPONSE STUDIES  

Microsoft Academic Search

ALM D. M., GARVES, R., STOLLER E. W. and WAX L. M. A computer-controlled seed germinator for realistic temperature response studies. BIOTRONICS 26, 31-37. The construction and operation of a computer-controlled seed germinator that implements realistic diurnal temperature regimens is described. A key feature of the apparatus is the ability to easily program sinusoidal fluctuations that seeds experience in the

D. M. ALM; R. A. GARVES; E. W. STOLLER; L. M. WAX

1997-01-01

162

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

Microsoft Academic Search

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

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

2007-01-01

163

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

PubMed

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

Srivastava, Garima; Kayastha, Arvind M

2014-01-01

164

Seed germination of six mature neotropical rain forest species in response to dehydration.  

PubMed

We studied effects of dehydration and rehydration on germination of seeds of six mature tropical rain forest species-Cupania glabra Swartz, Cymbopetalum baillonii Fries, Poulsenia armata (Miq.) Standl., Stemmadenia donnell-smithii (Rose) Woodson, Rheedia edulis Triana & Planch. and an understory palm Chamaedorea alternans H. Wendl.-from Veracruz, México. Before the seeds were sown, their water content was reduced by 0 (control), 30, 54 and 72% of their original water content. Dehydration affects the ability of seeds to rehydrate, as well as the rate and final percentage of germination when seeds are subsequently rehydrated. Seed survival and germination behavior showed three patterns: (1) C. baillonii, P. armata and S. donnell-smithii had greater tolerance to seed dehydration than C. glabra, C. alternans and R. edulis; (2) partial dehydration enhanced germinability of C. glabra and C. baillonii seeds; and (3) partial dehydration of C. alternans and R. edulis seeds resulted in delayed or sporadic germination. A relationship was found between the effects of dehydration on germination and the seasonality of seed production. PMID:12651519

Del Carmen Rodríguez, María; Orozco-Segovia, Alma; Sánchez-Coronado, María Esther; Sánchez-Coronado, Carlos Vázquez-Yanes

2000-05-01

165

4',4?,7,7?-Tetra-O-methylcupressuflavone Inhibits Seed Germination of Lactuca sativa.  

PubMed

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

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

2014-04-25

166

Heat shock effects on seed germination of five Brazilian savanna species.  

PubMed

Fire is considered an important factor in influencing the physiognomy, dynamics and composition of Neotropical savannas. Species of diverse physiognomies exhibit different responses to fire, such as population persistence and seed mortality, according to the fire frequency to which they are submitted. The aim of this study is to investigate the effects of heat shocks on seed germination of Anadenanthera macrocarpa (Benth.) Brenan, Dalbergia miscolobium Benth., Aristolochia galeata Mart. & Zucc., Kielmeyera coriacea (Spreng.) Mart. and Guazuma ulmifolia Lam., which are native species of the Brazilian savanna. The temperatures and exposure times to which the seeds were submitted were established according to data obtained in the field during a prescribed fire: 60 °C (10, 20 and 40 min), 80 °C (5, 10 and 20 min) and 100 °C (2, 5 and 10 min). Untreated seeds were used as controls. Seeds of A. galeata and K. coriacea showed high tolerance to most heat treatments, and seeds of A. macrocarpa showed a significant reduction in germination percentage after treatments of 80 °C and 100 °C. Treatments of 100 °C for 10 min reduced germination percentage for all species except G. ulmifolia, which has dormant seeds. For this species, germination was accelerated by heat treatments. The high temperatures applied did not interfere with the time to 50% germination (T(50) ) of the tolerant seeds. Seeds of the savanna species K. coriacea and A. galeata were more tolerant to heat shocks than seeds of the forest species A. macrocarpa. Guazuma ulmifolia, the forest species with seeds that germinate after heat shock, also occurs in savanna physiognomies. Overall, the high temperatures applied did not affect the germination rate of the tolerant seeds. PMID:22672775

Ribeiro, L C; Pedrosa, M; Borghetti, F

2013-01-01

167

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

PubMed Central

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

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

2013-01-01

168

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

Microsoft Academic Search

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

Tomasz A Paw?owski

2009-01-01

169

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

PubMed Central

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

Gorai, Mustapha; Gasmi, Hayet; Neffati, Mohamed

2011-01-01

170

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

Microsoft Academic Search

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

C. L. Leadem

1987-01-01

171

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

Microsoft Academic Search

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

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

2005-01-01

172

Subcuticular Secretion by Cactus Seeds Improves Germination by Means of Rapid Uptake and Distribution of Water  

Microsoft Academic Search

We report a formerly unknown mechanism in seeds which improves germination under relatively dry conditions. During seed development of several South American cacti, epidermal cells produce proteinaceous material that appears to pass through ectodesmata in the outer cell wall and which accumulates under the cuticle. Once moistened, this secretory layer readily absorbs water and distributes it over the seed surface.

ROB BREGMAN; PETER GRAVEN

1997-01-01

173

Subcuticular Secretion by Cactus Seeds Improves Germination by Means of Rapid Uptake and Distribution of Water  

Microsoft Academic Search

We report a formerly unknown mechanism in seeds which improves germination under relatively dry conditions. During seed development of several South American cacti, epidermal cells produce proteinaceous material that appears to pass through ectodesmata in the outer cell wall and which accumulates under the cuticle. Once moistened, this secretory layer readily absorbs water and distributes it over the seed surface.

ROB B REGMAN; P ETER G RAVEN

174

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

PubMed Central

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

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

2014-01-01

175

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

PubMed

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

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

2009-08-01

176

Hydrogen peroxide scavenging regulates germination ability during wheat (Triticum aestivum L.) seed maturation  

PubMed Central

Hydrogen peroxide (H2O2) promotes seed germination of cereal plants and ascorbic acid which acts as antioxidant suppresses the germination of wheat seeds, but the role of H2O2 scavenging on germination during seed maturation has not been demonstrated. We investigated relationship of germination, ascorbate, H2O2 scavenging enzymes and sensitivity to ascorbic acid (AsA) maturing seeds of two typical wheat (Triticum aestivum L.) cultivars, cvs. Shirogane-Komugi and Norin61. Shirogane-Komugi had marked high germination ability than Norin61 during seed maturation. Although the H2O2 content had no difference in the two culti-vars, sensitivity to AsA of Norin61 seeds was higher than that of Shirogane-Komugi seeds during seed maturation. The sensitivity to AsA closely correlated with germination characteristic in the two cultivars. Especially, at 28 days after pollination (DAP), sensitivity to AsA in Norin61 seeds was remarkably high. At that stage, no significant differences were observed in endogenous AsA level, ascorbate peroxidase (APX, EC 1.11.1.11) and dehydroascorbate reductase (DHAR, EC 1.8.5.1) activities in the two cultivars. However, catalase (CAT, EC 1.11.1.6) activity and CAT mRNA in Norin61 were remarkably higher than in Shirogane-Komugi. Sensitivity to AsA at 35 and 42 DAPs kept high levels in Norin61, and endogenous AsA and CAT activity in the seeds were significantly higher than in Shirogane-Komugi. These results revealed a direct correlation between germination and antioxidant sensitivity during the developmental stages of wheat seeds.

Yamamoto, Kouhei; Tawaratsumida, Tomoya; Yuasa, Takashi; Iwaya-Inoue, Mari

2008-01-01

177

Roles of brassinosteroids and related mRNAs in pea seed growth and germination.  

PubMed

The levels of endogenous brassinosteroids (BRs) and the expression of the biosynthesis/metabolism/perception genes involved have been investigated during the development and germination of pea (Pisum sativum) seeds. When seeds were rapidly growing, the level of biologically active BRs (brassinolide [BL] and castasterone [CS]) and the transcript levels of two BR C-6 oxidases (CYP85A1 and CYP85A6) reached a maximum, suggesting the significance of BL and CS in seed development. In the early stages of germination, CS, but not BL, appeared and its level increased in the growing tissues in which the transcript level of CYP85A1 and CYP85A6 was high, suggesting the significance of CS in seed germination and early seedling growth of pea. 6-Deoxocathasterone (6-deoxoCT) was the quantitatively major BR in mature seeds. At the early stage of germination, the level of 6-deoxoCT was specifically decreased, whereas the levels of downstream intermediates were increased. It seems that 6-deoxoCT is the major storage BR and is utilized during germination and early growth stages. The level of the mRNAs of BR biosynthesis and perception genes fluctuated during seed development. In mature seeds, most of mRNAs were present, but the level was generally lower compared with immature seeds. However, CYP90A9 mRNA rapidly increased during seed development and reached the maximum in mature seeds. The mRNAs stored in mature pea seeds seem to be utilized when seeds germinate. However, it was found that de novo transcription of mRNAs also starts as early as during seed imbibition. PMID:17322340

Nomura, Takahito; Ueno, Masaaki; Yamada, Yumiko; Takatsuto, Suguru; Takeuchi, Yasutomo; Yokota, Takao

2007-04-01

178

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

USGS Publications Warehouse

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.

Klinger, R.; Rejmanek, M.

2010-01-01

179

Major flowering time gene, FLOWERING LOCUS C, regulates seed germination in Arabidopsis thaliana  

PubMed Central

FLOWERING LOCUS C (FLC) is a major regulator of flowering responses to seasonal environmental factors. Here, we document that FLC also regulates another major life-history transition-seed germination, and that natural variation at the FLC locus and in FLC expression is associated with natural variation in temperature-dependent germination. FLC-mediated germination acts through additional genes in the flowering pathway (FT, SOC1, and AP1) before involving the abscisic acid catabolic pathway (via CYP707A2) and gibberellins biosynthetic pathway (via GA20ox1) in seeds. Also, FLC regulation of germination is largely maternally controlled, with FLC peaking and FT, SOC1, and AP1 levels declining at late stages of seed maturation. High FLC expression during seed maturation is associated with altered expression of hormonal genes (CYP707A2 and GA20ox1) in germinating seeds, indicating that gene expression before the physiological independence of seeds can influence gene expression well after any physical connection between maternal plants and seeds exists. The major role of FLC in temperature-dependent germination documented here reveals a much broader adaptive significance of natural variation in FLC. Therefore, pleiotropy between these major life stages likely influences patterns of natural selection on this important gene, making FLC a promising case for examining how pleiotropy influences adaptive evolution.

Chiang, George C. K.; Barua, Deepak; Kramer, Elena M.; Amasino, Richard M.; Donohue, Kathleen

2009-01-01

180

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

PubMed

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

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

2009-01-01

181

Copper Affects the Cotyledonary Carbohydrate Status During the Germination of Bean Seed  

Microsoft Academic Search

Seeds of bean (Phaseolus vulgaris L.) were germinated by soaking in distilled water or copper chloride solution. The relationships among copper excess treatment,\\u000a germination rate, dry weight, sugar contents, and carbohydrase activities in cotyledon were investigated. Heavy metal stress\\u000a provoked a diminution in germination rate and biomass mobilization, as compared with the control. A drastic disorder in soluble\\u000a sugars export,

Amira Sfaxi-Bousbih; Abdelilah Chaoui; Ezzedine El Ferjani

2010-01-01

182

Changes in oil, sugars and nitrogenous components during germination of sunflower seeds, Helianthus annuus  

Microsoft Academic Search

Since germination has been found to improve the nutritional quality of grains, sunflower seeds Helianthus annuus were germinated\\u000a for up to five days, and the cotyledons were analyzed for oil, sugar, free amino acid, non-protein nitrogen, lysine, tryptophan\\u000a and methionine contents. Protein was fractionated. Soaking and germination increased the non-protein nitrogen, total free\\u000a amino acid, lysine and tryptophan contents. Protein

R. Balasaraswathi; S. Sadasivam

1997-01-01

183

Interactive effects of salinity, nitrate, light, and seed weight on the germination of the halophyte Crithmum maritimum.  

PubMed

Interaction of salinity, nitrate, light, and seed weight on the germination of Crithmum maritimum was investigated. Seeds of three size categories were germinated at 0-200 mM NaCl with either 0, 5 or 20 mM KNO 3 . Experiments were done under darkness, white light, or red light. Regardless of seed weight, germination was maximal in distilled water. Under salinity, the smallest seeds showed the highest germination percentage. Salt impact was amplified by darkness, but was mitigated by nitrate supply, red light and their combination. At the same PPFD, germination of T2 seeds was higher, when exposed to red light than under white light, suggesting that germination was more influenced by the light type than by the PPFD. As a whole, not only salinity, nutrient availability, seed weight, and light, but also their interaction may control the germination of this halophyte. PMID:20015834

Atia, A; Debez, A; Rabhi, M; Smaoui, A; Abdelly, C

2009-12-01

184

Metabolism of trypsin-inhibitory proteins in the germinating seeds of kidney bean ( Phaseolus vulgaris )  

Microsoft Academic Search

A number of proteins with trypsin-inhibitory activity was separated by isoelectric focusing and their amounts measured in the extracts of the seeds of kidney bean at various stages of germination up to 16 days.

A. Pusztai

1972-01-01

185

Phytotoxic Potential of Gambel Oak on Ponderosa Pine Seed Germination and Initial Growth.  

National Technical Information Service (NTIS)

Water soluble leachates from Gambel Oak leaves reduces speed of germination and initial radical growth of ponderosa pine seeds in laboratory and greenhouse experiments. The combined effects of Gambel oak competition and allelopathy are implicated as contr...

M. G. Harrington

1987-01-01

186

RFLP mapping of QTLs conferring cold tolerance during seed germination in an interspecific cross of tomato  

Microsoft Academic Search

Most cultivars of tomato, Lycopersicon esculentum, are sensitive to low (chilling) temperatures (0–15 °C) during seed germination; however, genetic sources of cold (chilling) tolerance have been identified within the related wild species. The purpose of this study was to identify quantitative trait loci (QTLs) that contribute to cold tolerance during germination in tomato using a backcross population of an interspecific

M. R. Foolad; F. Q. Chen; G. Y. Lin

1998-01-01

187

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

Microsoft Academic Search

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

VAL RAGHAVAN

2002-01-01

188

Stimulation and Promotion of Germination in Opuntia ficus-indica Seeds  

Microsoft Academic Search

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

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

189

Light activates the degradation of PIL5 protein to promote seed germination through gibberellin in Arabidopsis  

Microsoft Academic Search

Summary Angiosperm seeds integrate various environmental signals, such as water availability and light conditions, to make a proper decision to germinate. Once the optimal conditions are sensed, gibberellin (GA) is synthesized, triggering germination. Among environmental signals, light conditions are perceived by phytochromes. However, it is not well understood how phytochromes regulate GA biosynthesis. Here we investigated whether phytochromes regulate GA

Eunkyoo Oh; Shinjiro Yamaguchi; Yuji Kamiya; Gabyong Bae; Won-Il Chung; Giltsu Choi

2006-01-01

190

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

Microsoft Academic Search

The germination rate, mineral (Ca, Fe, K, Mn) and carbohydrate (starch, soluble sugars, sucrose, glucose, fructose) contents and hydrolase activities in cotyledons and embryonic axes of bean seeds subjected to cadmium stress were investigated. Compared to the control, Cd caused a reduction in germination percent, embryo growth and in distribution of biomass, mineral and sugars between cotyledon and embryonic axis

Amira Sfaxi-Bousbih; Abdelilah Chaoui; Ezzedine El Ferjani

2010-01-01

191

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

Microsoft Academic Search

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

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

2008-01-01

192

Determining optimal seeding times for tall fescue using germination studies and spatial climate analysis  

Microsoft Academic Search

This paper describes a new approach for determining optimal seeding times using laboratory-based germination studies and spatial climate analysis, with tall fescue as the test species and China as the targeted application area. Since temperature is one of a number of influential environmental factors for germination and establishment of grass species, experiments were conducted to determine the effect of temperature

Hongfei Lu; Jinbo Shen; Xiaoqian Jin; David B. Hannaway; Christopher Daly; Michael D. Halbleib

2008-01-01

193

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

PubMed

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

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

1975-01-01

194

Efeitos de baixas doses de radiacao gama de cobalto-60 sobre sementes de feijao, arroz e rabanete. (Effects of cobalt-60 low doses radiation on bean, rice and radish seeds).  

National Technical Information Service (NTIS)

The effects of cobalt-60 gamma radiation on seeds of bean (Phaseolus vulgaris L.), rice (Oryza sativa L.) and radish (Raphanus sativus L.) were studied. Bean and rice seeds were irradiated with 3.5 and 7.7 Gy (32 Gy/h). There was an apparent acceleration ...

O. K. Kikuchi

1987-01-01

195

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

PubMed

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

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

2004-09-01

196

Seed germination and seedling growth in the arrow bamboo Fargesia qinlingensis  

Microsoft Academic Search

Improving natural regeneration of bamboos after they die following mass flowering is critical for conservation of giant pandas.\\u000a However, little is known about factors that affect seed germination and seedling growth of bamboos. We studied seed germination\\u000a and seedling growth in Fargesia qinlingensis, which mass flowered in a giant panda habitat in the Qinling Mountains of China in early 2000,

Wei Wang; Scott B. Franklin; Margaret C. Cirtain

2007-01-01

197

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

Microsoft Academic Search

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

S. P. J. Namal Senanayake; Fereidoon Shahidi

2000-01-01

198

Seed germination responses of four afromontane tree species to red\\/far-red ratio and temperature  

Microsoft Academic Search

The germination response of Cordia africana, Juniperus procera, Acacia abyssinica, and Faidherbia albida seeds to continuous exposure of various red to far-red ratios (R\\/FR) and constant-temperatures of 15, 20, 25 and 30°C were studied. Germination of C. africana seeds was strongly inhibited at low R\\/FR and it appears that this species has evolved a light quality sensing mechanism that prevents

Eshetu Yirdaw; Kari Leinonen

2002-01-01

199

Inhibitory Effects of Methyl Jasmonate on the Germination and Ethylene Production in Cocklebur Seeds  

Microsoft Academic Search

.   Methyl jasmonate (JA-Me) inhibited the germination of cocklebur (Xanthium pennsylvanicum Wallr.) seeds. The inhibition of the germination of cocklebur seeds treated with JA-Me at concentrations less than 300 ?m was nullified by ethylene applied exogenously, although the inhibitory effect of 1,000 ?m JA-Me was not recovered completely even by high concentrations of ethylene (10,000 ?L\\/liter). JA-Me inhibited ethylene production

M. Nojavan-Asghari; K. Ishizawa

1998-01-01

200

Studies on damage to sunflower seeds: water activity, germination, acidity index and aflatoxin B1 presence.  

PubMed

The significance of fungal contamination during the storage of sunflower seeds has been investigated. Samples were taken during 7 months at 45 day-intervals. Water activity, seed germination, presence of aflatoxin B1 and free fatty acids were monitored. It was demonstrated that water activity increased during storage, germinability decreased, the content of free fatty acid increased and so did the content of aflatoxin B1. PMID:2518323

Etcheverry, M; Dalcero, A; Chulze, S; Apro, N; Fusero, S; Farnochi, M

1989-07-01

201

Lipases in the storage tissues of peanut and other oil seeds during germination  

Microsoft Academic Search

The castor-bean endosperm-the best-studied material of reserve lipid hydrolysis in seed germination-was previously shown to have an acid lipase and an alkaline lipase having reciprocal patterns of development during germination. We studied oil seeds from 7 species, namely castor bean (Ricinus communis L.), peanut (Arachis hypogaea L.), sunflower (Helianthus annus L.), cucumber (Cucumis sativus L.), cotton (Gossypisum hirsutum L.), corn

Anthony H. C. Huang; Robert A. Moreau

1978-01-01

202

Germinated Cajanus cajan seeds as ingredients in pasta products: Chemical, biological and sensory evaluation  

Microsoft Academic Search

Pigeon peas (Cajanus cajan) seeds were germinated for 4 days at 20°C in darkness in order to improve the nutritional quality of seeds. Germination brought about a sharp reduction of ?-galactosides, phytic acid and trypsin inhibitor activity (83%, 61% and 36%, respectively) and an increment of vitamin B2 (145%), vitamin C (from negligible amounts to 14mg\\/100g d.m.), vitamin E (108%)

Alexia Torres; Juana Frias; Marisela Granito; Concepción Vidal-Valverde

2007-01-01

203

A GAMYB-like gene in tomato and its expression during seed germination  

Microsoft Academic Search

To understand the function of the gibberellin (GA) transduction pathway during germination, the transcription factor gene\\u000a GAMYB, which responds to the GA signal, has been studied in tomato (Solanum lycopersicum) seeds. This gene, called LeGAMYBL1 is present as a single copy, and is expressed in both the embryo and endosperm during seed germination in gib-1 mutant (non-GA producing) and wild-type

Xuemei Gong; J. Derek Bewley

2008-01-01

204

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

PubMed Central

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

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

205

Improving germination and vigour of aged and stored onion seeds by matriconditioning  

Microsoft Academic Search

Germination and vigour of accelerated aged (AA) and naturally stored onion seeds were examined. Accelerated ageing was conducted\\u000a at 40 ?C and 100 % relative humidity (RH). Non aged seeds were stored for 34 months at 3 or 15 ?C and 40, 60 or 90 % RH. To\\u000a restore seed viability, stored and aged seeds were matriconditioned with Micro-Cel E.

Anna Szafirowska; Mieczys?aw Grzesik; Hanna Habdas; Miros?awa Staniaszek

2002-01-01

206

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

Microsoft Academic Search

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

T. L. Springer

2005-01-01

207

Germination and Dormancy of Abscisic Acid- and Gibberellin-Deficient Mutant Tomato (Lycopersicon esculentum) Seeds (Sensitivity of Germination to Abscisic Acid, Gibberellin, and Water Potential).  

PubMed Central

Germination responses of wild-type (MM), abscisic acid (ABA)-deficient (sitw), and gibberellin (GA)-deficient (gib-1) mutant tomato (Lycopersicon esculentum Mill. cv Moneymaker) seeds to ABA, GA4+7, reduced water potential ([psi]), and their combinations were analyzed using a population-based threshold model (B.R. Ni and K.J. Bradford [1992] Plant Physiol 98: 1057-1068). Among the three genotypes, sitw seeds germinated rapidly and completely in water, MM seeds germinated more slowly and were partially dormant, and gib-1 seeds did not germinate without exogenous GA4+7. Times to germination were inversely proportional to the differences between the external osmoticum, ABA, or GA4+7 concentrations and the corresponding threshold levels that would either prevent ([psi]b, log[ABAb]) or promote (log[GAb]) germination. The sensitivity of germination to ABA, GA4+7, and [psi] varied widely among individual seeds in the population, resulting in a distribution of germination times. The rapid germination rate of sitw seeds was attributable to their low mean [psi]b (-1.17 MPa). Postharvest dormancy in MM seeds was due to a high mean [psi]b (-0.35 MPa) and a distribution of [psi]b among seeds such that some seeds were unable to germinate even on water. GA4+7 (100 [mu]M) stimulated germination of MM and gib-1 seeds by lowering the mean [psi]b to -0.75 MPa, whereas ABA inhibited germination of MM and sitw seeds by increasing the mean [psi]b. The changes in [psi]b were not due to changes in embryo osmotic potential. Rather, hormonal effects on endosperm weakening opposite the radicle tip apparently determine the threshold [psi] for germination. The analysis demonstrates that ABA- and GA-dependent changes in seed dormancy and germination rates, whether due to endogenous or exogenous growth regulators, are based primarily upon corresponding shifts in the [psi] thresholds for radicle emergence. The [psi] thresholds, in turn, determine both the rate and final extent of germination within the seed population.

Ni, B. R.; Bradford, K. J.

1993-01-01

208

Action spectra for phytochrome A- and B-specific photoinduction of seed germination in Arabidopsis thaliana.  

PubMed Central

We have examined the seed germination in Arabidopsis thaliana of wild type (wt), and phytochrome A (PhyA)- and B (PhyB)-mutants in terms of incubation time and environmental light effects. Seed germination of the wt and PhyA-null mutant (phyA) was photoreversibly regulated by red and far-red lights of 10-1,000 micromol m-2 when incubated in darkness for 1-14 hr, but no germination occurred in PhyB-null mutant (phyB). When wt seeds and the phyB mutant seeds were incubated in darkness for 48 hr, they synthesized PhyA during dark incubation and germinated upon exposure to red light of 1-100 nmol m-2 and far-red light of 0.5-10 micromol m-2, whereas the phyA mutant showed no such response. The results indicate that the seed germination is regulated by PhyA and PhyB but not by other phytochromes, and the effects of PhyA and PhyB are separable in this assay. We determined action spectra separately for PhyA- and PhyB-specific induction of seed germination at Okazaki large spectrograph. Action spectra for the PhyA response show that monochromatic 300-780 nm lights of very low fluence induced the germination, and this induction was not photoreversible in the range examined. Action spectra for the PhyB response show that germination was photoreversibly regulated by alternate irradiations with light of 0.01-1 mmol m-2 at wavelengths of 540-690 nm and 695-780 nm. The present work clearly demonstrated that PhyA photoirreversibly triggers the germination upon irradiations with ultraviolet, visible and far-red light of very low fluence, while PhyB controls the photoreversible effects of low fluence. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5

Shinomura, T; Nagatani, A; Hanzawa, H; Kubota, M; Watanabe, M; Furuya, M

1996-01-01

209

Project Explorer: Get Away Special #007. [alloy solidification, seed germination, crystal growth, and radio transmission of payload data  

NASA Technical Reports Server (NTRS)

Tentatively scheduled to fly on STS-17 (41G), this get away special aims to demonstrate amateur radio transmissions to global ground stations in the English language. Experiments No. 1, 2, and 3 use the micro-gravity of space flight to study the solidification of lead-antimony and aluminum-copper alloys, the germination of radish seeds, and the growth of potassium-tetracyanoplatinate hydrate crystals in an aqueous solution. Flight results are to be compared with Earth-based data. Experiment No. 4 (the Marshall Amateur Radio Club Experiment - MARCE) features radio transmissions and also provides timing for the start of all other experiments. A microprocessor obtains real-time data from all experiments as well as temperature and pressure measurements within the GAS canister. These data are to be transmitted on previously announced amateur radio frequencies after they are converted into the English language by a digitalker for general reception. The support structure for the G #007 experiments consists of two primary plates and four bumper assemblies.

Henderson, A. J., Jr.

1984-01-01

210

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

NASA Technical Reports Server (NTRS)

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

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

1992-01-01

211

Effect of Water Stress on the Carbohydrate Metabolism of Citrullus lanatus Seeds during Germination 1  

PubMed Central

Gluconeogenesis in Citrullus lanatus seeds is a post germinative event. Increases in isocitrate lyase activity and incorporation of radioactivity from [2-14C]acetate into sugars occur only after radicle emergence. During germination, the seeds appear to rely on carbohydrate as the respiratory substrate. At this time, glycolysis, the pentose phosphate pathway, and the tricarbocyclic acid cycle seem to be functional. Utilization of raffinose during germination appears to be important. Water stress, which completely inhibits germination, has a marked effect on carbohydrate metabolism. The rate of 14CO2 release from [2-14C]acetate, [1-14C]glucose, and [6-14C]glucose is lower in the stressed seeds than the control seeds during the respiratory lag phase. However, in the stressed seeds neither glycolysis, the pentose phosphate pathway, nor the tricarboxylic acid cycle is completely inhibited. In contrast to the control seeds in which raffinose content sharply declines after 12 h of incubation, raffinose content in the stressed seeds remains fairly constant. The respiratory lag phase of the control seeds coincides with a lower reducing substance content, glucose content, and fructose content than in the stressed seeds during the corresponding incubation period.

Botha, Frederik C.; Small, Johannes G. C.

1985-01-01

212

Effects of different pretreatments on germination of Prunus serotina seed sources.  

PubMed

Establishing intensive plantations of fast growing hardwood tree species that have high market values in the forest industry can narrow the gap between Turkey's demand and the supply of quality hardwood products. Black cherry (P. serotina Ehrh.) is a fast growing hardwood species with a high market value. Introducing and intensively growing black cherry (BC) in Turkey may significantly reduce the country's quality wood shortage. Adequate seed germination constitutes the first essential step for successful establishments. In this paper effects of different pretreatments, including artificial and natural stratification, on the seeds of different BC seed sources (SSs) were studied. Pretreatments had substantial effects on the dormancy breaking and germination behaviours of the SSs. Consecutive periods of complex warm and cold artificial stratification regimes longer than 90 days or natural stratification (where seeds were assumed to be naturally exposed to this complexity) resulted in best dormancy breaking and, in turn, germination among all pretreatments. Deeper dormancy and reduced germination rates of some BC seeds as the altitude of the source increases might suggest an ecological adaptive strategy of the species. BC may have deeper morphophysiological dormancy than is commonly believed. Seed size may have a positive effect on seed germination. PMID:17717993

Esen, Derya; Yildiz, Oktay; Sarginci, Murat; Isik, Kani

2007-01-01

213

Germination behaviour of seeds of Withania somnifera (L.) Dunal: a high value medicinal plant.  

PubMed

In order to evolve a quick method for smooth and optimum germination for Withania somnifera- a medicinally efficacious multipurpose plant, present investigation was carried to study the effect of physico-chemical treatments, storage, temperature, photoperiod and growth regulators (GA3, IAA, IBA, 2-4 D and BA) on germinability. The most effective treatment is GA3 at 150 ?g/ml concentration at 25 °C. The optimal temperature for germination is 25 °C and continuous light favored germination showing that photoperiod has a significant role. The seedlings derived from seeds performed well when grown in a glasshouse. The data have implications for conservation and cultivation of the species studied. PMID:24431513

Khanna, Punit K; Kumar, Arun; Chandra, Ratna; Verma, V

2013-07-01

214

Induction of seed germination in Orobanche spp. by extracts of traditional Chinese medicinal herbs.  

PubMed

The co-evolution of Orobanche spp. and their hosts within the same environment has resulted in a high degree of adaptation and effective parasitism whereby the host releases parasite germination stimulants, which are likely to be unstable in the soil. Our objective was to investigate whether extracts from non-host plants, specifically, Chinese medicinal plants, could stimulate germination of Orobanche spp. Samples of 606 Chinese medicinal herb species were extracted with deionized water and methanol. The extracts were used to induce germination of three Orobanche species; Orobanche minor, Orobanche cumana, and Orobanche aegyptiaca. O. minor exhibited a wide range of germination responses to the various herbal extracts. O. cumana and O. aegyptiaca exhibited an intermediate germination response to the herbal extracts. O. minor, which has a narrow host spectrum, showed higher germination rates in response to different herbal extracts compared with those of O. cumana and O. aegyptiaca, which have a broader host spectrum. Methanolic extracts of many Chinese herbal species effectively stimulated seed germination among the Orobanche spp., even though they were not the typical hosts. The effective herbs represent interesting examples of potential trap crops. Different countries can also screen extracts from indigenous herbaceous plants for their ability to induce germination of Orobanche spp. seeds. The use of such species as trap plants could diminish the global soil seed bank of Orobanche. PMID:22527522

Ma, YongQing; Zhang, Wei; Dong, ShuQi; Ren, XiangXiang; An, Yu; Lang, Ming

2012-03-01

215

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

PubMed Central

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

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

2012-01-01

216

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

PubMed Central

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

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

2014-01-01

217

Genetic mapping within the wheat D genome reveals QTL for germination, seed vigour and longevity, and early seedling growth  

Microsoft Academic Search

Quantitative trait loci (QTL) controlling germination, seed vigour and longevity, and early seedling growth were identified\\u000a using a set of common wheat lines carrying known D genome introgression segments. Seed germination (capacity, timing, rate\\u000a and synchronicity) was characterized by a standard germination test, based either on the 1 mm root protrusion (germination\\u000a sensu stricto) or the development of normal seedlings. To

S. Landjeva; U. Lohwasser; A. Börner

2010-01-01

218

THE EFFECT OF SOWING BRUCHID DAMAGED BEAN (Phaseolus vulgaris L.) SEEDS ON GERMINATION, PLANT DEVELOPMENT AND YIELD  

Microsoft Academic Search

A study to investigate the effect of sowing bruchid-damaged bean seeds on germination, plant development and grain yield was conducted at Sokoine University of Agriculture (SUA) in Morogoro between November 1999 and April 2000. Undamaged seed and seeds damaged by bruchids with one to four holes were planted in plastic pots and placed in the glasshouse. Germination, plant development, and

M. S. Chipungahelo; R. N. Misangu; S. O. W. M. Reuben

219

Protein Mobilization in Germinating Mung Bean Seeds Involves Vacuolar Sorting Receptors and Multivesicular Bodies1(W)(OA)  

Microsoft Academic Search

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

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

220

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

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

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

221

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

PubMed

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

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

2012-03-01

222

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

PubMed

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

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

2009-12-01

223

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

PubMed Central

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.

2012-01-01

224

Effect of Bruchid Beetles (Burchidius Arabicus Decelle) Infestation on the Germination of Acacia tortilis (Forssk.) Hayne) Seeds  

Microsoft Academic Search

The role of bruchid beetle infestation on seed germination of Acacia tortilis (Forssk.) Hayne) Mimosaceae under different incubation temperatures and degrees of scarification was studied under controlled conditions. Results indicate that seed germination was highest (96%) in scarified seeds at 25-35ºC incubation temperature, whereas, it was only 28% in intact seeds. Seeds infected by bruchid beetles with one or two

M. Al; Jabr Ahmed

2008-01-01

225

Changes in oil, sugars and nitrogenous components during germination of sunflower seeds, Helianthus annuus.  

PubMed

Since germination has been found to improve the nutritional quality of grains, sunflower seeds Helianthus annuus were germinated for up to five days, and the cotyledons were analyzed for oil, sugar, free amino acid, non-protein nitrogen, lysine, tryptophan and methionine contents. Protein was fractionated. Soaking and germination increased the non-protein nitrogen, total free amino acid, lysine and tryptophan contents. Protein content and dry weight decreased. The oil content decreased significantly after 72 hours of germination. The reducing sugars increased gradually until day 'five' of germination. The saline soluble albumin and globulin fractions decreased while the glutelin content increased during germination. No changes were noticed in the prolamin and methionine contents. PMID:9498696

Balasaraswathi, R; Sadasivam, S

1997-01-01

226

Effect of municipal solid waste compost on seed germination of rice, wheat and cucumber  

Microsoft Academic Search

Water extracts of municipal solid waste compost (MSWC) were applied to seed of three crops v - v rice ( Oryza sativa, L.), wheat ( Triticum aestivum, L.) and cucumber ( Cucumis sativa, L.). Severe suppression of germination index (GI), root length (RL) and shoot length (SL) were observed with the seeds treated with 1 v : v 7.5 MSWC

R. Pal; P. Bhattacharyya

2003-01-01

227

CHANGES IN SENSITIVITY OF MAIZE CHROMOSOMES TO X RAYS DURING SEED GERMINATION  

Microsoft Academic Search

Changes in the radiosensitivity of maize seeds during early stages of ; germination were studied by means of somatic-mutation techniques. Seeds ; heterozygous for the ygâ (yellow-green) locus were irradiated with 800 r of ; x rays after soaking in running tap water up to 42 hr. Yellow-green sectors, ; representing mutations affecting the dominant ygâ locus, in leaves 4

Richard L. Latterell; Dale M. Steffensen

1962-01-01

228

Influence of seed nitrogen content and biofertilizer priming on wheat germination in salinity stress conditions  

Microsoft Academic Search

In order to study the effects of seed nitrogen content and biofertilizer priming on germination indices of wheat seeds under salinity stress, a factorial experiment based on a completely randomized design with four replications was conducted in 2009. Experimental factors consisted of: (1) the application of different nitrogen fertilizer rates (0, 55, 110 and 165 kg ha N) on parent

Jabbar Fallahi; Parviz Rezvani Moghaddam; Mahdi Nassiri Mahallati; Mohammad Ali Behdani; Mahsa Aghhavani Shajari; Mohammad Behzad Amiri

2012-01-01

229

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

Microsoft Academic Search

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

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

2009-01-01

230

Soil Treatments for Improving Seed Germination of Rare and Endangered Sikkim Himalayan Rhododendrons  

Microsoft Academic Search

A field survey was conducted to find out the status of the availability of rhododendrons of Sikkim Himalaya. Rhododendrons, denizens of high altitude, have a characteristic slow growth rate. Seeds of rhododendron are clearly distinguished from their outer micro-and macro-morphological variability from species to species. Seed germination of 10 elite species of rhododendrons were investigated in variou s treatments using

Kuashal Kumar Singh; Sandeep Kumar; Anita Pandey

2008-01-01

231

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

Microsoft Academic Search

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

Hua Chen; M. A. Maun

1999-01-01

232

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

Microsoft Academic Search

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

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

2007-01-01

233

Seed Germination of GA-Insensitive sleepy1 Mutants Does Not Require RGL2 Protein Disappearance in Arabidopsis  

Microsoft Academic Search

We explore the roles of gibberellin (GA) signaling genes SLEEPY1 (SLY1) and RGA-LIKE2 (RGL2) in regulation of seed germinationinArabidopsisthaliana,aplantinwhichthehormoneGAisrequiredforseedgermination.Seedgerminationfailure in the GA biosynthesis mutant ga1-3 is rescued by GA and by mutations in the DELLA gene RGL2, suggesting that RGL2 represses seed germination. RGL2 protein disappears before wild-type seed germination, consistent with the model that GA stimulates germination by causing

Tohru Ariizumi; Camille M. Steber

234

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

Microsoft Academic Search

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

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

2006-01-01

235

The effects of Fusilade (Fluazifop- p -butyl) on germination, mitotic frequency and ?-amylase activity of lentil ( Lens culinaris Medik.) seeds  

Microsoft Academic Search

In this study, seed germination percentages, effects on phases of mitosis and ?-amylase enzyme activity of lentil seeds treated\\u000a with four different concentrations (0.25, 0.5, 1 and 1.5%) of Fusilade (Fluazifop-p-butyl) were determined. Median EC (effective concentration) values were calculated according to seed germination percentages\\u000a after treatment for 72 h. Germination percentages of primary lentil roots decreased with increasing Fusilade concentrations.

Feruzan Dane; Filiz Ekinci Sanal; Tulin Aktac

2007-01-01

236

[Acid vacuolar invertase in hibernating and germinating seeds of the horse chestnut].  

PubMed

A high water content is maintained in the tissues of the axial organs of horse chestnut seeds after the fruit is shed and down to the time the seeds germinate. The plant cell vacuoles, features of whose metabolism can influence the cells' preparation to initiate growth in germination, are preserved. It was shown that the activity of acid invertase and its capacity to digest both sucrose and raphinose remain stable throughout the period of hibernation and the transition to germination, as do the molecular weight of its subunits (63 and 65 kDa) and multimer (500 to 550 kDa). The activity of the enzyme increases when the seeds swell under optimal conditions for germination; this is associated with the synthesis of new molecules of the enzyme in long-lived mRNA matrices. The storability of the enzyme in the vacuoles of hibernating seeds, together with the increase in its activity when seeds coming out of hibernation swell, ensures the rapid hydrolysis of sucrose issuing from the seeds' cotyledons, thus leading to increased osmotic pressure and, as a result, the beginning of cell elongation, i.e., germination. PMID:20058784

Obrucheva, N V; Litiagina, S V

2009-01-01

237

Modification of Seed Germination Performance through Cold Plasma Chemistry Technology  

Microsoft Academic Search

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

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

2000-01-01

238

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

PubMed

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

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

2012-07-13

239

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

PubMed Central

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

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

2013-01-01

240

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

Microsoft Academic Search

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

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

2010-01-01

241

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

Microsoft Academic Search

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

I. Debeaujon; M. Koornneef

2000-01-01

242

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

PubMed

The rupture of the seed coat and that of the endosperm were found to be two sequential events in the germination of Sisymbrium officinale L. seeds, and radicle protrusion did not occur exactly in the micropylar area but in the neighboring zone. The germination patterns were similar both in the presence of gibberellins (GA(4+7)) and in presence of ethrel. The analysis of genes involved in GAs synthesis and breakdown demonstrated that (1) SoGA2ox6 expression peaked just prior to radicle protrusion (20-22 h), while SoGA3ox2 and SoGA20ox2 expression was high at early imbibition (6 h) diminishing sharply thereafter; (2) the accumulation of SoGA20ox2 transcript was strongly inhibited by paclobutrazol (PB) as well as by inhibitors of ET synthesis and signaling (IESS) early after imbibition (6 h), while SoGA3ox2 and SoGA2ox6 expression was slowly depressed as germination progressed; (3) ethrel and GA(4+7) positively or negatively affected expression of SoGA3ox2, SoGA20ox2, and SoGA2ox6, depending on the germination period studied. Regarding genes involved in ET synthesis, our results showed that SoACS7 was expressed, just prior to radicle emergence while SoACO2 expression slowly increased as germination progressed. Both genes were strongly inhibited by PB but were almost unaffected by externally added ethrel or GA(4+7). These results suggest that GAs are more important than ET during the early stages of imbibition, while ET is more important at the late phases of germination of S. officinale L. seeds. PMID:20012087

Iglesias-Fernández, Raquel; Matilla, Angel J

2010-02-01

243

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

PubMed Central

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

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

2011-01-01

244

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

PubMed

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

Yago, Jonar I; Roh, Jae-Hwan; Bae, Soon-do; Yoon, Young-Nam; Kim, Hyun-Ju; Nam, Min-Hee

2011-09-01

245

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

PubMed

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

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

2014-08-01

246

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

PubMed Central

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

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

2010-01-01

247

Differential sensitivity to cadmium in germinating seeds of three cultivars of faba bean ( Vicia faba L.)  

Microsoft Academic Search

The reserve mobilization was analysed in germinating seeds of faba bean (Vicia faba) exposed to treatment with a toxic cadmium concentration for 4 days. When the behaviours of three cultivars were compared\\u000a with regard to the germination rate, the following order of sensitivity to cadmium was observed: Aguadulce and Luz de otoño\\u000a showed 59 and 19% of inhibition from controls, respectively,

Sondès Rahoui; Abdelilah Chaoui; Ezzeddine El Ferjani

2008-01-01

248

Germination ecology of Scorpiurus subvillosus L. seeds: the role of temperature and storage time  

Microsoft Academic Search

Scorpiurus subvillosus L., wide spread in pastures of Mediterranean basin, is disappearing in the native pastures of the Hyblean plateau (Sicily,\\u000a southern Italy), because of overgrazing and intensive management techniques. Moreover, it exhibits seed coat dormancy, which\\u000a delays and reduces germination preventing its diffusion. This paper represents a first attempt in order to investigate changing\\u000a in germination determined by storage

Fabio Gresta; Giovanni Avola; Valerio Abbate

2007-01-01

249

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

Microsoft Academic Search

Effects of volatile and gaseous metabolites of swelling seeds of pea, bean, wheat, corn, cucumber, tomato, lentil, carrot,\\u000a red pepper and lettuce on germination of spores of five genera of fungi were found to depend rather on the fungal than on\\u000a the plant genus. Germination of spores ofBotrytis cinerea, Mucor racemosus andTrichoderma viride was most severely inhibited. Spores ofVerticillium dahliae

V. ?atská; A. F. Apifi; V. Van?ura

1975-01-01

250

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

Microsoft Academic Search

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

F. Corbineau; R. M. Rudnicki; D. Côme

1988-01-01

251

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

Microsoft Academic Search

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.

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

2006-01-01

252

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

PubMed Central

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

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

2008-01-01

253

Patterns of Protein Oxidation in Arabidopsis Seeds and during Germination1[w  

PubMed Central

Increased cellular levels of reactive oxygen species are known to occur during seed development and germination, but the consequences in terms of protein degradation are poorly characterized. In this work, protein carbonylation, which is an irreversible oxidation process leading to a loss of function of the modified proteins, has been analyzed by a proteomic approach during the first stages of Arabidopsis (Arabidopsis thaliana) seed germination. In the dry mature seeds, the legumin-type globulins (12S cruciferins) were the major targets. However, the acidic ?-cruciferin subunits were carbonylated to a much higher extent than the basic (?) ones, consistent with a model in which the ?-subunits are buried within the cruciferin molecules and the ?-subunits are more exposed to the outside. During imbibition, various carbonylated proteins accumulated. This oxidation damage was not evenly distributed among seed proteins and targeted specific proteins as glycolytic enzymes, mitochondrial ATP synthase, chloroplastic ribulose bisphosphate carboxylase large chain, aldose reductase, methionine synthase, translation factors, and several molecular chaperones. Although accumulation of carbonylated proteins is usually considered in the context of aging in a variety of model systems, this was clearly not the case for the Arabidopsis seeds since they germinated at a high rate and yielded vigorous plantlets. The results indicate that the observed specific changes in protein carbonylation patterns are probably required for counteracting and/or utilizing the production of reactive oxygen species caused by recovery of metabolic activity in the germinating seeds.

Job, Claudette; Rajjou, Loic; Lovigny, Yoann; Belghazi, Maya; Job, Dominique

2005-01-01

254

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

PubMed

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

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

2014-05-01

255

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

PubMed

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

Polevik, N D

2013-01-01

256

Winery wastewater inhibits seed germination and vegetative growth of common crop species.  

PubMed

The ability to reuse winery wastewater would be of significant benefit to the wine industry, as it could potentially be a cost-effective method of wastewater management, whilst at the same time providing a valuable water resource. This study investigated the effects of different dilutions of a semi-synthetic winery wastewater on the growth and germination of four common crop species in a glasshouse study; barley (Hordeum vulgare), millet (Pennisetum glaucum), lucerne (Medicago sativa) and phalaris (Phalaris aquatica). The wastewater caused a significant delay in the germination of lucerne, millet and phalaris, although overall germination percentage of all species was not affected. Vegetative growth was significantly reduced in all species, with millet being the most severely affected. The germination index of barley correlated very highly (r(2)=0.99) with barley biomass, indicating that barley seed germination bioassays are highly relevant to plant growth, and therefore may be of use as a bioassay for winery wastewater toxicity. PMID:20452120

Mosse, Kim P M; Patti, Antonio F; Christen, Evan W; Cavagnaro, Timothy R

2010-08-15

257

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

PubMed Central

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

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

1989-01-01

258

[A comparative study on seed germination of 15 grass species in Keeqin Sandyland].  

PubMed

A laboratory study was made on the germination characteristics of freshly-collected seeds of grass species at the Wulanaodu area of Keeqin Sandyland in Eastern Inner-Mongolia. Of the 15 species examined, 8 species including Clinelymus dahuricus, Cleistogenes squarrosa, Pappophorum boreale, Spodiopogon sibiricus, Phragmites communis, Chloris virgata, Arundinella hirta, Pennisetum alopecuroides had a germination rate of over 80%, but 4 species including Echinochloa hispidula, Hemarthria compressa, Tragus berteronianus and Setaria viridis had a value of less than 10%. Spodiopogon sibiricus, Eragrostis pilosa, Phragmites communis, Chloris virgata, Clinelymus dahuricus, Pappophorum boreale, Digitaria cilliaris and Cleistogenes squrrosa began to germinate within 1-3 days after the test began, while Setaria viridis, Tragus berteronianus and Hemarthria compressa failed to germinate in a period of more than 10 days. For the species such as Digitaria cilliaris, Echinochloa hispidula, Phragmites communis, Eragrostis pilosa and Spodiopogon sibiricus, their germination period was less than 10 days, while Clinelymus dahuricus and Pappophorum boreale had a germination period of more than 20 days. The days required for half the final germination rate to be reached were: 2 days for Chloris virgata, 3 days for Phragmites communis, 4 days for Spodiopogon sibiricus, 5 days for Clinelymus dahuricus and Cleistogenes squarrosa, 7 days for Arundinella hirta and Pappophorum boreale, and 10 days for Pennisetum alopecuriodes. Compared with the Sheffield region in Britain, the Wulanaodu area of Kerqin Sandyland had a higher proportion of annul grasses with a low germination rate and a longer germination period, and the perennial grasses at the Wulanaodu area had an approximately same germination rate, but a longer germination period. During germination, ruderals showed the potential for risk-sharring, and thus, they had a relatively higher disturbance-resistance capacity. PMID:14732991

Liu, Zhimin; Li, Xuehua; Li, Rongping; Jiang, Deming; Cao, Chengyou

2003-09-01

259

Effects of a warmer climate on seed germination in the subarctic  

PubMed Central

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

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

2009-01-01

260

Joint effects of acetochlor and urea on germinating characteristics of crop seeds.  

PubMed

In order to evaluate ecological risk of agrochemicals in common use, joint toxic effects of acetochlor and urea on germinating characteristics of Chinese cabbage (Brassica Pekinensis Rupr) seeds were investigated using the water-culture method and the soil-culture method. The results indicated that excessive application of acetochlor and urea, when the concentrations were higher than 31.3 mg x kg(-1) for acetochlor and 500 mg x kg(-1) for urea, had strong inhibitory effects on the rate of seed germination, root elongation and hypocotyl length of Chinese cabbage. The inhibitory rate of the germinating characteristics of Chinese cabbage seeds was significantly increased with an increase in the concentration of acetochlor or urea. The two agrochemicals in water had a stronger toxicity than these in the soil at the same concentration. Among the three indexes, hypocotyl length was the most sensitive to the toxicity of acetochlor and urea. PMID:16089323

Xiao, Hong; Zhou, Qixing; Ma, Lena Q

2005-05-01

261

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

PubMed

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

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

2012-01-01

262

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

PubMed

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

Brar, Jasmine; Anand, Manju; Sood, Anil

2013-01-01

263

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

PubMed

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

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

2010-10-01

264

TEMPERATURE-DEPENDENT GERMINATION AND ENDO-? ? - MANNANASE ACTIVITY IN SESAME SEEDS  

Microsoft Academic Search

The effects of temperature on germination and endo-?-mannanase activity in seeds of Sesamum indicum was investigated. The minimum germination temperature (Tmin) lies between 12.8°C and 13.2°C while the maximum temperature (Tmax) is located between 45.5°C and 46°C. Germinabilities are statistically not different from estimated viability (88%) between 18.8°C and 43.2°C. The Mann- Whitney test indicated the interval 31.9°C to 35.1°C

FABIAN BORGHETTI; MARCOS SILVEIRA BUCKERIDGE; LAURO MORHY; EDIVALDO XIMENES FERREIRA FILHO

265

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

PubMed

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

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

2013-01-01

266

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

PubMed Central

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

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

2013-01-01

267

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

PubMed Central

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

Pradhan, Bharat K.; Badola, Hemant K.

2012-01-01

268

Effect of storage conditions and storage periods on seed germination in eleven populations of Swertia chirayita: a critically endangered medicinal herb in Himalaya.  

PubMed

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

Pradhan, Bharat K; Badola, Hemant K

2012-01-01

269

Optimal germination condition by sulfuric acid pretreatment to improve seed germination of Sabina vulgaris Ant  

Microsoft Academic Search

Understanding the germination traits of plants is important not only for understanding natural regeneration processes but\\u000a also for developing seedling production techniques for planting. Sabina vulgaris Ant. is a common species used for reforestation in semi-arid areas of the Mu-Us Desert, in Inner Mongolia, China, but its\\u000a extremely low germination rate, both in situ and in vivo, is a bottleneck

Ayumi Tanaka-Oda; Tanaka Kenzo; Kenji Fukuda

2009-01-01

270

Arabidopsis CPR5 Independently Regulates Seed Germination and Postgermination Arrest of Development through LOX Pathway and ABA Signaling  

Microsoft Academic Search

The phytohormone abscisic acid (ABA) and the lipoxygenases (LOXs) pathway play important roles in seed germination and seedling growth and development. Here, we reported on the functional characterization of Arabidopsis CPR5 in the ABA signaling and LOX pathways. The cpr5 mutant was hypersensitive to ABA in the seed germination, cotyledon greening and root growth, whereas transgenic plants overexpressing CPR5 were

Guilan Gao; Shengchun Zhang; Chengfeng Wang; Xiang Yang; Yaqin Wang; Xiaojun Su; Jinju Du; Chengwei Yang; Diane Bassham

2011-01-01

271

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

Microsoft Academic Search

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

BILQUEES GUL; M. AJMAL KHAN

2008-01-01

272

Seed germination ecology of Polymnia canadensis (Asteraceae), a monocarpic species of the North American Temperate Deciduous Forest  

Microsoft Academic Search

The seed germination of Polymnia canadensis was studied in relation to its wide variation in life history and its ecology as a mostly facultative biennial, a life cycle type that is rare in stable forest habitats in eastern North America. The seed dormancy and germination characteristics of P. canadensis were like some other herbaceous woodland species of diverse life cycle

Martin H. Bender; Jerry M. Baskin; Carol C. Baskin

2003-01-01

273

Comparative study of seed germination and growth of Kochia prostrata and Kochia scoparia (Chenopodiaceae) under salinity  

Microsoft Academic Search

Soils of arid regions of Central Asia contain salts of different types that may differentially affect seed germination and plant development. We studied effect of NaCl, Na2SO4, 2NaCl + KCl + CaCl2 and 2Na2SO4+K2SO4+MgSO4 on germination of Kochia prostrata and Kochia scoparia seeds under a range of concentrations from 0.5 to 5% and at two constant temperature regimes +22 °C and +6 °C. The observed salt

N. S. Orlovsky; U. N. Japakova; I. Shulgina; S. Volis

2011-01-01

274

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

Microsoft Academic Search

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

M. Zaheer Ahmed; M. Ajmal Khan

2010-01-01

275

Effect of storage temperature and dormancy-breaking treatments on seed germination, moisture content and seed vigor in gum karaya (Sterculia urens Roxb.)  

Microsoft Academic Search

Sterculia urens is a commercially important tree with wide applications. Although it reproduces by seed, its germination requirements are not known. The seed also suffers with dormancy. The present study is an attempt to understand the proper storage conditions and also the type of dormancy in seeds of Sterculia urens. The optimum temperature for storage of seeds was found to

P. Subhashini Devi; B. Satyanarayana; A. Arundhati; T. Raghava Rao

2012-01-01

276

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

USGS Publications Warehouse

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.

Jutila, H. M.

2001-01-01

277

Enhancement of Salinity Tolerance during Rice Seed Germination by Presoaking with Hemoglobin.  

PubMed

Salinity stress is an important environmental constraint limiting the productivity of many crops worldwide. In this report, experiments were conducted to investigate the effects of seed presoaking by bovine hemoglobin, an inducer of heme oxygenase-1 (HO-1), on salinity tolerance in rice (Oryza sativa) plants. The results showed that different concentrations of the hemoglobin (0.01, 0.05, 0.2, 1.0, and 5.0 g/L) differentially alleviated the inhibition of rice seed germination and thereafter seedling shoot growth caused by 100 mM NaCl stress, and the responses of 1.0 g/L hemoglobin was the most obvious. Further analyses showed that application of hemoglobin not only increased the HO-1 gene expression, but also differentially induced catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities or transcripts, thus decreasing the lipid peroxidation in germinating rice seeds subjected to salt stress. Compared with non-hemoglobin treatment, hemoglobin presoaking also increased the potassium (K) to sodium (Na) ratio both in the root and shoot parts after salinity stress. The effect is specific for HO-1 since the potent HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX) blocked the positive actions of hemoglobin on seed germination and seedling shoot growth. Overall, these results suggested that hemoglobin performs an advantageous role in enhancement of salinity tolerance during rice seed germination. PMID:21731454

Xu, Sheng; Hu, Bing; He, Ziyi; Ma, Fei; Feng, Jianfei; Shen, Wenbiao; Yang, Jie

2011-01-01

278

Changes in Level and Activity of Phospholipid Transfer Protein during Maturation and Germination of Maize Seeds  

PubMed Central

The variations of the amounts of phospholipid transfer proteins (PLTP), determined by ELISA and immunoblotting methods, were followed during the maturation and germination of maize (Zea mays L.) seeds. Changes of the amounts of PLTP occur during seed maturation. The levels of PLTP, low in the first 3 weeks after fecondation, strongly raised 3 to 5 weeks after, then reached and maintained a high value (10% of total soluble proteins) during the last steps of maturation. These variations, determined by ELISA, are in accordance with the observations made by immunoblotting. Changes in phospholipid transfer activity were also found when protein extracts prepared from seeds at different stages of maturation were assayed for transfer activity. The levels of PLTP were also determined during the germination of maize seeds and the early growth of the plantlets, both in the endosperm and the aerial parts. While no major change was observed in the endosperm, a high increase in PLTP level was found in the aerial part of the plantlet, both by ELISA and immunoblotting. An enhancement of the phospholipid transfer activity was parallely observed in the protein extracts of plantlets at various stages of germination. These results are consistent with an in vivo correlation between the synthesis of phospholipid transfer protein, observed during the maturation and germination of maize seeds, and the biogenesis of membranes which involves intracellular movements of phospholipids. Images Figure 1 Figure 3 Figure 5

Grosbois, Michele; Guerbette, Francoise; Kader, Jean-Claude

1989-01-01

279

No evidence of adverse effects on germination, emergence, and fruit yield due to space exposure of tomato seeds.  

PubMed

Seeds of 'Rutgers California Supreme' tomato (Lycopersicon esculentum Mill.) were exposed to outer space conditions aboard the long duration exposure facility (LDEF) satellite in the space exposed experiment developed for students (SEEDS) project of the National Aeronautics and Space Administration (NASA). Seeds aboard the LDEF were packed in dacron bags forming four layers per sealed canister. Some of these seeds were used in Oklahoma and Florida for studies of germination, emergence, and fruit yield. Among all measured variables in three experiments, there was only one significant main effect of canister 2 versus canister 7 (for mean time to germination) and only one main effect of layer (for seedling shoot dry weight). There also were only two inconsistent canister x layer interactions in the germination tests. The contrast of Earth-based control seed versus space-exposed seed was significant four times: in Oklahoma in 1991 the mean time to germination of space-exposed seeds and the days to 50% of final germination were 0.7 days less than for Earth-based seeds, and in Florida in 1992 seedling percent emergence and shoot dry weight were increased by space exposure. Fruit yield and marketability were unaffected in plants grown from space-exposed seeds. These results support student findings from the SEEDS project, and provide evidence that tomato seeds can survive in space for several years without adverse effects on germination, emergence, and fruit yield. PMID:11539352

Kahn, B A; Stoffella, P J

1996-05-01

280

Polyamines, IAA and ABA during germination in two recalcitrant seeds: Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm)  

PubMed Central

Background and Aims Plant growth regulators play an important role in seed germination. However, much of the current knowledge about their function during seed germination was obtained using orthodox seeds as model systems, and there is a paucity of information about the role of plant growth regulators during germination of recalcitrant seeds. In the present work, two endangered woody species with recalcitrant seeds, Araucaria angustifolia (Gymnosperm) and Ocotea odorifera (Angiosperm), native to the Atlantic Rain Forest, Brazil, were used to study the mobilization of polyamines (PAs), indole-acetic acid (IAA) and abscisic acid (ABA) during seed germination. Methods Data were sampled from embryos of O. odorifera and embryos and megagametophytes of A. angustifolia throughout the germination process. Biochemical analyses were carried out in HPLC. Key Results During seed germination, an increase in the (Spd + Spm) : Put ratio was recorded in embryos in both species. An increase in IAA and PA levels was also observed during seed germination in both embryos, while ABA levels showed a decrease in O. odorifera and an increase in A. angustifolia embryos throughout the period studied. Conclusions The (Spd + Spm) : Put ratio could be used as a marker for germination completion. The increase in IAA levels, prior to germination, could be associated with variations in PA content. The ABA mobilization observed in the embryos could represent a greater resistance to this hormone in recalcitrant seeds, in comparison to orthodox seeds, opening a new perspective for studies on the effects of this regulator in recalcitrant seeds. The gymnosperm seed, though without a connective tissue between megagametophyte and embryo, seems to be able to maintain communication between the tissues, based on the likely transport of plant growth regulators.

Pieruzzi, Fernanda P.; Dias, Leonardo L. C.; Balbuena, Tiago S.; Santa-Catarina, Claudete; dos Santos, Andre L. W.; Floh, Eny I. S.

2011-01-01

281

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

PubMed Central

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

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

2012-01-01

282

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

Microsoft Academic Search

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

Haruna Ishikawa

2010-01-01

283

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

PubMed Central

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

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

2011-01-01

284

EFFECTS OF LIGHT ON SEED GERMINATION, GROWTH PATTERN OF STRAITS RHODODENDRON (Melastoma malabathricum L.)  

Microsoft Academic Search

The effects of media on seed germination and general growth patterns of M. malabathricum under different light and temperature regimes were studied in the laboratory and insect-proof house conditions in University of Malaya. 50 fresh or dried seeds of M. malabathricum were placed in each petri-dish and moistened with water or solutions of the chemical media, KNO3, H2O2 and HNO3

Mahdi Faravani; Baki Bin Bakar

285

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

Microsoft Academic Search

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

Laurel K. Goode; Michael F. Allen

2009-01-01

286

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

Microsoft Academic Search

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

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

2002-01-01

287

Effect of storage temperature and extraction methods on dormancy and germination of true potato seed  

Microsoft Academic Search

Seed treatments, methods of extraction and storage temperature were examined for effects on viability and dormancy of true\\u000a potato seed. Dormancy of 4x?2x (S. tuberosum ×S. phureja) hybrids was eliminated after 7 months at room temperature and after 10 months at 4 C. However, data on the velocity and\\u000a uniformity of germination (coefficient of velocity) revealed the presence of a

Vincent L. D’Antonio; Neil A. McHale

1988-01-01

288

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

Microsoft Academic Search

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

A. J. Sanhewe; R. H. Ellis

1996-01-01

289

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

Microsoft Academic Search

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

Murray K. Laubhan; Terry L. Shaffer

2006-01-01

290

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

PubMed

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

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

2010-09-01

291

Effect of new organic supplement (Panchgavya) on seed germination and soil quality.  

PubMed

We studied the suitability of Panchgavya (five products of cow), new organic amendment, application on seed germination, plant growth, and soil health. After characterization, Panchgavya was mixed with water to form different concentration and was tested for seed germination, germination index, and root and shoot growth of different seedlings. Four percent solution of Panchgavya was applied to different plants to test its efficacy. Panchgavya and other two organic amendments were incorporated in soil to test the change of soil chemical and microbiological parameters. Panchgavya contained higher nutrients as compared to farm yard manure (FYM) and vermicompost. Its application on different seeds has positively influenced germination percentage, germination index, root and shoot length, and fresh and dry weight of the seedling. Water-soluble macronutrients including pH and metal were positively and negatively correlated with the growth parameters, respectively. Four percent solution of Panchgavya application on some plants showed superiority in terms of plant height and chlorophyll content. Panchgavya-applied soil had higher values of macro and micronutrients (zinc, copper, and manganese), microbial activity as compared to FYM, and vermicompost applied soils. Application of Panchgavya can be gainfully used as an alternative organic supplement in agriculture. PMID:24234225

Jain, Paras; Sharma, Ravi Chandra; Bhattacharyya, Pradip; Banik, Pabitra

2014-04-01

292

Proteomic analysis of response to long-term continuous stress in roots of germinating soybean seeds.  

PubMed

Germination is a complex process, highly dependent on various environmental factors, including temperature and water availability. Germinating soybean seeds are especially vulnerable to unfavorable environmental conditions and exposure to long-term abiotic stresses may result in diminishing much of the yield and most importantly - restrained germination. In the present study, a proteomic approach was employed to analyze influence of cold and osmotic stress on roots of germinated soybean (Glycine max, L.) seeds. Seeds were germinating under continuous conditions of cold stress (+10°C/H2O), osmotic stress (+25°C/-0.2MPa) as well as cold and osmotic stress combined (+10°C/-0.2MPa). Proteome maps established for control samples and stress-treated samples displayed 1272 CBB-stained spots. A total of 59 proteins, present in both control and stress-treated samples and showing significant differences in volume, were identified with LC/nanoESI-MS. Identified proteins divided into functional categories, revealed 9 proteins involved in plant defense, 8 proteins responsible for plant destination and storage and 10 proteins involved in various tracks of carbohydrate metabolism. Furthermore, a number of proteins were assigned to electron transport, range of metabolic pathways, secondary metabolism, protein synthesis, embryogenesis and development, signal transduction, cellular transport, translocation and storage. By analyzing differences in expression patterns, it was possible to trace the soybean response to long-term abiotic stress as well as to distinguish similarities and differences between response to cold and osmotic stress. PMID:23394790

Swigonska, Sylwia; Weidner, Stanislaw

2013-03-15

293

Lifting DELLA Repression of Arabidopsis Seed Germination by Nonproteolytic Gibberellin Signaling1[C][W][OPEN  

PubMed Central

DELLA repression of Arabidopsis (Arabidopsis thaliana) seed germination can be lifted either through DELLA proteolysis by the ubiquitin-proteasome pathway or through proteolysis-independent gibberellin (GA) hormone signaling. GA binding to the GIBBERELLIN-INSENSITIVE DWARF1 (GID1) GA receptors stimulates GID1-GA-DELLA complex formation, which in turn triggers DELLA protein ubiquitination and proteolysis via the SCFSLY1 E3 ubiquitin ligase and 26S proteasome. Although DELLA cannot be destroyed in the sleepy1-2 (sly1-2) F-box mutant, long dry after-ripening and GID1 overexpression can relieve the strong sly1-2 seed dormancy phenotype. It appears that sly1-2 seed dormancy results from abscisic acid (ABA) signaling downstream of DELLA, since dormant sly1-2 seeds accumulate high levels of ABA hormone and loss of ABA sensitivity rescues sly1-2 seed germination. DELLA positively regulates the expression of XERICO, an inducer of ABA biosynthesis. GID1b overexpression rescues sly1-2 germination through proteolysis-independent DELLA down-regulation associated with increased expression of GA-inducible genes and decreased ABA accumulation, apparently as a result of decreased XERICO messenger RNA levels. Higher levels of GID1 overexpression are associated with more efficient sly1 germination and increased GID1-GA-DELLA complex formation, suggesting that GID1 down-regulates DELLA through protein binding. After-ripening results in increased GA accumulation and GID1a-dependent GA signaling, suggesting that after-ripening triggers GA-stimulated GID1-GA-DELLA protein complex formation, which in turn blocks DELLA transcriptional activation of the XERICO inhibitor of seed germination.

Ariizumi, Tohru; Hauvermale, Amber L.; Nelson, Sven K.; Hanada, Atsushi; Yamaguchi, Shinjiro; Steber, Camille M.

2013-01-01

294

Arabidopsis thaliana DOF6 negatively affects germination in non-after-ripened seeds and interacts with TCP14  

PubMed Central

Seed dormancy prevents seeds from germinating under environmental conditions unfavourable for plant growth and development and constitutes an evolutionary advantage. Dry storage, also known as after-ripening, gradually decreases seed dormancy by mechanisms not well understood. An Arabidopsis thaliana DOF transcription factor gene (DOF6) affecting seed germination has been characterized. The transcript levels of this gene accumulate in dry seeds and decay gradually during after-ripening and also upon seed imbibition. While constitutive over-expression of DOF6 produced aberrant growth and sterility in the plant, its over-expression induced upon seed imbibition triggered delayed germination, abscisic acid (ABA)-hypersensitive phenotypes and increased expression of the ABA biosynthetic gene ABA1 and ABA-related stress genes. Wild-type germination and gene expression were gradually restored during seed after-ripening, despite of DOF6-induced over-expression. DOF6 was found to interact in a yeast two-hybrid system and in planta with TCP14, a previously described positive regulator of seed germination. The expression of ABA1 and ABA-related stress genes was also enhanced in tcp14 knock-out mutants. Taken together, these results indicate that DOF6 negatively affects seed germination and opposes TCP14 function in the regulation of a specific set of ABA-related genes.

Rueda-Romero, Paloma; Barrero-Sicilia, Cristina; Gomez-Cadenas, Aurelio; Carbonero, Pilar; Onate-Sanchez, Luis

2012-01-01

295

Dual action of respiratory inhibitors: inhibition of germination and prevention of dormancy induction in lettuce seeds.  

PubMed

;Grand Rapids' lettuce Lactuca sativa L. seeds germinate readily at 15 degrees C but poorly at 25 degrees C in darkness. When held in dark at 25 degrees C for an extended period, the ungerminated seeds become dormant as shown by their inability to germinate or transfer to 15 degrees C in darkness. Induction of dormancy at 25 degrees C was prevented by exposure to CN(-), azide, salicylhydroxamic acid (SHAM), dinitrophenol, and pure N(2) as determined by subsequent germination at 15 degrees C on removal of inhibitors. The effectiveness of inhibitors to break dormancy declined as dormancy intensified. At relatively low levels, CN(-), SHAM, and azide promoted dark germination at 25 degrees C while at high levels they were inhibitory. Uptake of O(2) by seeds held at 25 degrees C for 4 days in 1.0 millimolar KCN was inhibited by 67% but was promoted 61% when KCN was removed. Correspondingly greater inhibition (79%) and promotion (148%) occurred when 1.0 millimolar SHAM was added to KCN solution. When applied alone, SHAM had little effect on O(2) uptake. These data indicate that Cyt pathway of respiration plays a dominant role in the control of both dormancy induction and germination of lettuce seeds, and ;alternative pathway' is effectively engaged in presence of CN(-). The channeling of respiratory energy use for processes governing germination or dormancy is subject to control by physical and chemical factors.A scheme is proposed that illustrates compensatory use of energy for processes controlling dormancy induction and germination. A block of germination, e.g. by low water potential polyethylene glycol solution or a supraoptimal temperature spares energy to be utilized for dormancy induction while a block of dormancy induction by low levels of CN(-) (similar to GA and light effects) drives germination. Blocking both processes by inhibitors (e.g. CN(-), CN(-) + SHAM) presumably leads to accumulation of ;reducing power' with consequent improvement in O(2) uptake and oxidation rates of processes controlling germination or dormancy induction upon removal of the inhibitors. PMID:16664144

Khan, A A; Zeng, G W

1985-04-01

296

Comparison of germination and seed vigor of sunflower in two contaminated soils of different texture  

NASA Astrophysics Data System (ADS)

Phytoremediation as an emerging low-cost and ecologically friendly alternative to the conventional soil remediation technologies has gained a great deal of attention and into lots of research. As a kind of the methods that use of green plants to remediate heavy metals contaminated soils, the early growth status of plant seeds in the contaminated environmental directly affects the effect of phytoremediation. Germination test in the water (aqueous solution of heavy metal) is generally used for assessing heavy metal phytotoxicity and possibility of plant growth, but there is a limit. Because soil is commonly main target of phytoremediation, not the water. The bioavailability of heavy metals in the soil also depends on the texture. So soil texture is an important factor of phytoremediation effect. Sunflower is the representative species which have good tolerance to various heavy metals; furthermore, the seeds of sunflower can be used as the raw-material for producing bio-diesel. The objectives of this research were to investigate germination rate of sunflowers in various heavy metal contaminated soils and to compare the seedling vigor index (SVI) of sunflower in two contaminated soils of different texture. Sunflower (Helianthusannuus L.) seeds were obtained from a commercial market. In order to prove the soil texture effect on heavy metal contaminated soil, germination tests in soil were conducted with two different types of soil texture (i.e., loam soil and sandy loam soil) classified by soil textural triangle (defined by USDA) including representative soil texture of Korea. Germination tests in soil were conducted using KS I ISO 11260-1 (2005) for reference that sunflower seeds were incubated for 7 days in dark at 25 ± 1 Celsius degree. The target heavy metals are Nickel (Ni) and Zinc (Zn). The Ni and Zn concentrations were 0, 10, 50, 100, 200, 300, 500 mg-Ni/kg-dry soil, and 0, 10, 50, 100, 300, 500, 900 mg-Zn/kg-dry soil, respectively. After germination test for 7 days, germination rate of sunflower was calculated, and shoot and root lengths were also measured. According to the results of germination tests, the seeds germination rates were reduced with increasing heavy metal concentrations in both loam soil and sandy loam soil. The SVI values in loam soil in more than in sandy loam soil. Keywords: phytoremediation, sunflower, soil texture, germination test ACKNOWLEDGEMENT This work is supported by the Korea Ministry of the Environment as 'The GAIA (Geo-Advanced Innovative Action) Project'.

Zhao, Xin; Han, Jaemaro; Lee, Jong Keun; Kim, Jae Young

2014-05-01

297

Study on the seed production and germination dynamic of common milkweed (Asclepias syriaca L.).  

PubMed

The common milkweed causes considerable damages on the agricultural and nature conservation areas. The area occupied by this weed is continuously bigger. The common milkweed is spread over North-America between the 35th and 50th degree of western Latitude and 60th 103rd degree of longitude. Millions of hectares are polluted by this weed in the United States. Important is its spread also in Asia (Iraq), in Europe (Carpathian Basin, Poland, Bulgaria, Switzerland, France, Austria, Germany), as well as in the area of the former Soviet Union (Belorussia, The Baltic Countries, Caucasus, and the Ukraine). Though the basic biological characters of this plant are well known, still its control is a significant problem, the damages increase on the areas occupied by this weed. We collect seed samples from several Hungarian areas in 2007. After the sampling we determined the average sprout length and the number of follicle as well as the average seed numbers in the follicle. We determined also the weight of thousand seeds of the resultant seed samples. At natural circumstances the seedlings appear at a soil temperature of 15 degrees C during the end of April and first week of May. Under Laboratory circumstances the dormancy of the seeds ceases continuously from November on, germinate at a temperature of 20-30 degrees C, the maximum germination can be achieved in the first part of April. At January we started germination examinations with the seeds in Petri dish, among laboratory condition. PMID:19226850

Sárkány, S E; Lehoczky, E; Nagy, P

2008-01-01

298

Effects of drying on sunflower seed oil quality and germination  

Microsoft Academic Search

Sunflower seed (SunGro 380) were harvested 101 to 121 days after planting, and their moisture levels were between 43 and 15%.\\u000a The seed were dried at 35, 53, 72, and 88 C to a final moisture level of 10% or below. Drying air flow was 2000 m3\\/hr.\\/m3 seed. Temperature had no effect on peroxide values, total oil, or fatty acid

W. Herbert Morrison; J. A. Robertson

1978-01-01

299

Nitrogen effects on seed germination and seedling growth  

Microsoft Academic Search

Recent evidence associates the persistence of invasive plant species with disturbance and fluctuations in distinct forms of mineral N in soils. We conducted soil and hydroponic experi- ments to investigate the influence of N form and availability on germination and seedling development of 2 invasive annual grasses, cheatgrass (Bromus tectorum) and medusahead (Taeniatherum caput-medusae) and 6 perennial grasses, blue- bunch

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

2003-01-01

300

Inactivation of the ELIP1 and ELIP2 genes affects Arabidopsis seed germination.  

PubMed

Light regulates Arabidopsis seed germination through the phyB/PIL5 (PHYTOCHROME INTERACTING FACTOR 3-LIKE 5) transduction pathway, and we have previously shown that the Dof transcription factor DOF AFFECTING GERMINATION1 (DAG1) is a component of this pathway. By means of microarray analysis of dag1 and wild type developing siliques, we identified the EARLY LIGHT-INDUCED PROTEIN1 and 2 (ELIP1 and ELIP2) genes among those deregulated in the loss-of-function dag1 mutant. We analysed seed germination of elip single and double mutants, of elip?dag1 double mutants as well as of elip1?elip2?dag1 triple mutant under different environmental conditions. We show that ELIP1 and ELIP2 are involved in opposite ways in the control of this developmental process, in particular under abiotic (light, temperature, salt) stress conditions. PMID:21299564

Rizza, Annalisa; Boccaccini, Alessandra; Lopez-Vidriero, Irene; Costantino, Paolo; Vittorioso, Paola

2011-06-01

301

Metabolism of triacylglycerol species during seed germination in fatty acid sunflower (Helianthus annuus) mutants.  

PubMed

Sunflower mutant lines with high saturated fatty acid content (palmitic or stearic) in the oil have a completely different set of triacylglycerols (TAG), some of which were not found in standard sunflowers. For optimum seed germination, all of these new TAG species must be effectively catabolized. The behavior of the TAG composition during germination in cotyledons of all these mutant lines showed two different phases: an initial phase (between 0 and 2 days after sowing) with a higher catalytic activity and a preference for TAG containing at least two oleic acid molecules and a second phase with lower TAG degradation rate and a low preference for TAG containing two saturated fatty acids usually accompanied by linoleic acid. Despite the elevated content of saturated fatty acids in some TAG species, the total TAG degradation rate and germination process were similar in these lines, suggesting that sunflower seed lipases do not show a marked preference for any TAG species. PMID:10725147

Fernández-Moya, V; Martínez-Force, E; Garcés, R

2000-03-01

302

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

PubMed Central

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

YAMAZAKI, JUN; MIYOSHI, KAZUMITSU

2006-01-01

303

Germination, growth rates, and electron microscope analysis of tomato seeds flown on the LDEF  

NASA Technical Reports Server (NTRS)

The tomato seeds were flown in orbit aboard the Long Duration Exposure Facility (LDEF) for nearly six years. During this time, the tomato seeds received an abundant exposure to cosmic radiation and solar wind. Upon the return of the LDEF to earth, the seeds were distributed throughout the United States and 30 foreign countries for analysis. The purpose of the experiment was to determine the long term effect of cosmic rays on living tissue. Our university analysis included germination and growth rates as well as Scanning Electron Microscopy and X-ray analysis of the control as well as Space-exposed tomato seeds. In analyzing the seeds under the Electron Microscope, usual observations were performed on the nutritional and epidermis layer of the seed. These layers appeared to be more porous in the Space-exposed seeds than on the Earth-based control seeds. This unusual characteristic may explain the increases in the space seeds growth pattern. (Several test results show that the Space-exposed seeds germinate sooner than the Earth-Based seeds. Also, the Space-exposed seeds grew at a faster rate). The porous nutritional region may allow the seeds to receive necessary nutrients and liquids more readily, thus enabling the plant to grow at a faster rate. Roots, leaves and stems were cut into small sections and mounted. After sputter coating the specimens with Argon/Gold Palladium Plasma, they were ready to be viewed under the Electron Microscope. Many micrographs were taken. The X-ray analysis displayed possible identifications of calcium, potassium, chlorine, copper, aluminum, silicon, phosphate, carbon, and sometimes sulfur and iron. The highest concentrations were shown in potassium and calcium. The Space-exposed specimens displayed a high concentration of copper and calcium in the two specimens. There was a significantly high concentration of copper in the Earth-based specimens, whereas there was no copper in the Space-exposed specimens.

Hammond, Ernest C., Jr.; Bridgers, Kevin; Brown, Cecelia Wright

1995-01-01

304

Determination of Kinetic and Thermodynamic Parameters that Describe Isothermal Seed Germination: A Student Research Project.  

ERIC Educational Resources Information Center

Describes a project for students to collect and fit data to a theoretical mathematical model that describes the rate of isothermal seed germination, including activation energy for substrate and produce and the autocatalytic reaction, and changes in enthalpy, entropy, and the Gibb's free energy. (Author/SK)

Hageseth, Gaylord T.

1982-01-01

305

In Vivo Effects of Barbituates on Seed Germination and Seedling Growth.  

ERIC Educational Resources Information Center

A simple, low-cost experimental system can be used to demonstrate the "in vivo" effects of barbituates on seed germination and seedling growth behavior in different plant species. Lipid solubility and concentration of individual barbituates both affect the response. List of materials needed, procedures used, and typical results obtained are…

Kordan, H. A.

1984-01-01

306

Seed germination as a biological test for the study of fluctuating phenomena  

Microsoft Academic Search

The original method to perform the P test of Piccardi (1962) was used in a study on correlation between variations in the time of precipitation of bismuth oxichloride and seed germination carried out at daily and three hour intervals from 26 March until 23 April, 1971. The chemical tests were repeated each day at 12.00 hr and at 18.00 hr,

G. Abrami; G. Piccardi

1973-01-01

307

Beneficial effects of cold-moist stratification on seed germination behaviors of Abies pindrow and Picea smithiana  

Microsoft Academic Search

A study was conducted to evaluate the effect of GA3, moist-chilling and temperature on seed germination of Abies pindrow and Picea smithiana from five different provenances. Seeds were soaked in GA3 (10 mg·L?1) for 24 h, then chilled at 3–5°C for 15 days. Four temperature regimes viz. 10°C, 15°C, 20°C and 25°C were used for stimulating\\u000a seed germination. Results showed

Balbir Singh Rawat; Vinod Prasad Khanduri; Chandra Mohan Sharma

2008-01-01

308

Effects of mycorrhizal fungi on symbiotic seed germination of Pecteilis susannae (L . ) Rafin (Orchidaceae), a terrestrial orchid in Thailand  

Microsoft Academic Search

Symbiotic seed germination of Pecteilis susannae (L.) Rafin was investigated using 11 fungal isolates recovered from roots of four Thai terrestrial orchids (P. susannae, Eulophia spectabilis, Paphiopedilum bellatulum and Spathoglottis affinis). Seed germination and protocorm development were evaluated up to 133 days after sowing. Protocorm development was most advanced,\\u000a up to stage 5 (elongation of the first leaf), when seeds were

Ruangwut Chutima; Bernard Dell; Saisamorn Lumyong

2011-01-01

309

Germination response of alder and birch seeds to applied gibberellic acid and priming treatments in combination with chilling  

Microsoft Academic Search

The effects of seed moisture content (MC), gibberellic acid (GA3) concentration, chilling and priming pretreatments on the germination of common alder (Alnus glutinosa) and downey birch (Betula pubescens) seeds were examined. After treatment, the seeds were allowed to germinate for 42 days at 15 °C or 20 °C (dark)\\/30 °C (light).\\u000a Treatment responses were similar at both temperatures and in

Norberto De Atrip; Conor O’Reilly

2007-01-01

310

Variation in germination characteristics of some seed origins of Pinus wallichiana A B Jacks from the western Himalaya  

Microsoft Academic Search

Seeds of kail collected from 10 localities in the western Himalaya were germinated at 4 temperatures viz 20°, 28°, 34° and\\u000a 40°C after storage in dry cold conditions in freezer. The seed lots representing different localities differed in the capacity\\u000a and rate of germination. At lower temperature of incubation (20°C) most of the seed lots exhibited varying degree of dormancy.

R C Thapliyal; D P Uniyal; M S Rawat

1985-01-01

311

Effect of different pre-sowing seed treatments on the germination of Leucaena leucocephala (Lam.) and Acacia farnesiana (L.)  

Microsoft Academic Search

Leucaena leucocephala and Acacia farnesiana are tree species used for several agricultural purposes in the Mediterranean region. The seeds of these species exhibit dormancy,\\u000a causing delayed germination. Two experiments were conducted to investigate the effect of pre-sowing treatments (scarification,\\u000a hot water, or soaking) on seed germination of L. leucocephala and A. farnesiana. In one experiment, seeds were exposed to three

Maher J. TadrosNezar; Nezar H. Samarah; Ahmad M. Alqudah

312

Maternal and direct effects of elevated CO 2 on seed provisioning, germination and seedling growth in Bromus erectus  

Microsoft Academic Search

Elevated CO2 can affect plant fitness not only through its effects on seed production but also by altering the quality of seeds and therefore\\u000a germination and seedling performance. We collected seeds from mother plants of Bromus erectus grown in field plots at ambient and elevated CO2 (m-CO2, maternal CO2) and germinated them in the greenhouse in a reciprocal design under

Thomas Steinger; Rolf Gall; Bernhard Schmid

2000-01-01

313

Strict requirement of fluctuating temperatures as a reliable gap signal in Picris hieracioides var. japonica seed germination  

Microsoft Academic Search

Picris\\u000a hieracioides var. japonica (Asteraceae), which grows in occasionally disturbed habitats such as riverbanks, is rarely observed under dense vegetation.\\u000a We examined the effect of the experience and timing of receiving leaf-transmitted light in gap-detecting seed germination\\u000a in this plant. Seeds under unfiltered light, which simulated the light conditions of seeds on the soil surface in a canopy\\u000a gap, germinated

Yukio Honda; Kazuhiro Katoh

2007-01-01

314

Seed Germination Patterns in Green Dragon (Arisaema dracontium, Araceae)  

Microsoft Academic Search

Arisaema dracontium (green dragon) is a perennial herb that is widely distributed in eastern North America. However, in Canada, at the northern edge of its distribution, the species is designated as ''vulnerable'' with respect to conservation status. In natural populations, seedlings are uncommon; the present study was undertaken in order to characterize seed and seedling properties in green dragon. Seeds

J. Yang; J. Lovett-Doust; L. Lovett-Doust

1999-01-01

315

An allelopathic substance exuded from germinating watermelon seeds  

Microsoft Academic Search

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

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

1998-01-01

316

Dynamic Quantitative Trait Loci Analysis of Seed Reserve Utilization during Three Germination Stages in Rice  

PubMed Central

In this study, one rice population of recombinant inbred lines (RILs) was used to determine the genetic characteristics of seed reserve utilization during the early (day 6), middle (day 10) and late (day 14) germination stages. The seedling dry weight (SDW) and weight of the mobilized seed reserve (WMSR) were increased, while the seed reserve utilization efficiency (SRUE) decreased, during the process of seed germination. The SDW and WMSR were affected by the seed weight, while the SRUE was not affected by the seed weight. A total of twenty unconditional and twenty-one conditional additive QTLs and eight epistatic QTLs were identified at three germination stages, and the more QTLs were expressed at the late germination stage. Among them, twelve additive and three epistatic QTLs for SDW, eight additive and three epistatic QTLs for WMSR and thirteen additive and two epistatic QTLs for SRUE were identified, respectively. The phenotypic variation explained by each additive QTL, epistatic QTL and QTL × development interaction ranged from 6.10 to 23.91%, 1.79 to 6.88% and 0.22 to 2.86%, respectively. Two major additive QTLs qWMSR7.1 and qSRUE4.3 were identified, and each QTL could explain more than 20% of the total phenotypic variance. By comparing the chromosomal positions of these additive QTLs with those previously identified, eleven QTLs might represent novel genes. The best four cross combinations of each trait for the development of RIL populations were selected. The selected RILs and the identified QTLs might be applicable to improve rice seed reserve utilization by the marker-assisted selection approach.

Huang, Xi; Lai, Yanyan; Wang, Ling; Du, Wenli; Wang, Zhoufei; Zhang, Hongsheng

2013-01-01

317

Dynamic quantitative trait loci analysis of seed reserve utilization during three germination stages in rice.  

PubMed

In this study, one rice population of recombinant inbred lines (RILs) was used to determine the genetic characteristics of seed reserve utilization during the early (day 6), middle (day 10) and late (day 14) germination stages. The seedling dry weight (SDW) and weight of the mobilized seed reserve (WMSR) were increased, while the seed reserve utilization efficiency (SRUE) decreased, during the process of seed germination. The SDW and WMSR were affected by the seed weight, while the SRUE was not affected by the seed weight. A total of twenty unconditional and twenty-one conditional additive QTLs and eight epistatic QTLs were identified at three germination stages, and the more QTLs were expressed at the late germination stage. Among them, twelve additive and three epistatic QTLs for SDW, eight additive and three epistatic QTLs for WMSR and thirteen additive and two epistatic QTLs for SRUE were identified, respectively. The phenotypic variation explained by each additive QTL, epistatic QTL and QTL × development interaction ranged from 6.10 to 23.91%, 1.79 to 6.88% and 0.22 to 2.86%, respectively. Two major additive QTLs qWMSR7.1 and qSRUE4.3 were identified, and each QTL could explain more than 20% of the total phenotypic variance. By comparing the chromosomal positions of these additive QTLs with those previously identified, eleven QTLs might represent novel genes. The best four cross combinations of each trait for the development of RIL populations were selected. The selected RILs and the identified QTLs might be applicable to improve rice seed reserve utilization by the marker-assisted selection approach. PMID:24244592

Cheng, Xinxin; Cheng, Jinping; Huang, Xi; Lai, Yanyan; Wang, Ling; Du, Wenli; Wang, Zhoufei; Zhang, Hongsheng

2013-01-01

318

Interactions between ethylene-bis-nitrourethane and Gibberellic acid during the germination of lettuce seed.  

PubMed

Exposing lettuce seed (variety Grand Rapids) to temperatures from 30°-42° C inhibits subsequent germination at 25° C. This inhibition can be overcome by the addition of gibberellic acid (GA) either during or after the heat treatment. Ethylene-bis-nitrourethane (EBNU) and ethylene dinitramine (EDNA), although without effect when applied alone, have been shown to increase the activity of GA when present in admixture during the heat treatment. The compounds act synergistically only when the seeds are kept at 30° and 35° C for 72 hours or longer.EBNU and EDNA do not increase the effectiveness of GA in breaking natural or heat induced dormancy in lettuce seeds. PMID:24522734

Morgan, D G

1968-09-01

319

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

PubMed Central

Initial soil water conditions play a critical role when seeding is the primary approach to revegetate post-mining areas. In some semi-arid climates, such as the Brigalow Belt Bioregion in eastern Australia, extensive areas are affected by open-cut mining. Together with erratic rainfall patterns and clayey soils, the Brigalow Belt denotes a unique biome which is representative of other water-limited ecosystems worldwide. Apart from other environmental stressors, germination is governed by the water potential of the surrounding soil material. While previous studies have confirmed the high tolerance of Brigalow (Acacia harpophylla) seeds to a broad range of temperature and salinity, the question of how soil water potential triggers seed germination remains. In this study, we used three replicates of 50 seeds of Brigalow to investigate germination in relation to water potential as an environmental stressor. Solutions of Polyethylene Glycol (PEG 6000) were applied to expose seeds to nine osmotic water potentials ranging from soil water saturation (0 MPa) and field capacity (?.01 to ?.03 MPa) to the permanent wilting point (?1.5 MPa). We measured germinability (number of germinated seeds relative to total number of seeds per lot) and mean germination time (mean time required for maximum germination of a seed lot) to quantify germination. Based on the empirical data of the germination we estimated the parameters of the hydrotime model which simulates timing and success of seed emergence. Our findings indicate that Brigalow seeds are remarkably tolerant to water stress, with germination being observed at a water potential as low as ?1.5 MPa. Likewise, the average base water potential of a seed population (hydrotime model) was very low and ranged between ?1.533 and ?1.451 MPa. In general, Brigalow seeds germinate opportunistically over a broad range of abiotic conditions related to temperature, salinity, and water availability. Direct seeding and germination of native plants on post-mining land may be an effective and economically viable solution in order to re-establish plant communities. However, due to their capacity to reproduce asexually, alternative rehabilitation approaches such as transplantation of whole soil-root compartments may become attractive for restoration ecologists to achieve safe, stable, and non-polluting ecosystems.

Kailichova, Yolana; Baumgartl, Thomas

2014-01-01

320

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

PubMed

Initial soil water conditions play a critical role when seeding is the primary approach to revegetate post-mining areas. In some semi-arid climates, such as the Brigalow Belt Bioregion in eastern Australia, extensive areas are affected by open-cut mining. Together with erratic rainfall patterns and clayey soils, the Brigalow Belt denotes a unique biome which is representative of other water-limited ecosystems worldwide. Apart from other environmental stressors, germination is governed by the water potential of the surrounding soil material. While previous studies have confirmed the high tolerance of Brigalow (Acacia harpophylla) seeds to a broad range of temperature and salinity, the question of how soil water potential triggers seed germination remains. In this study, we used three replicates of 50 seeds of Brigalow to investigate germination in relation to water potential as an environmental stressor. Solutions of Polyethylene Glycol (PEG 6000) were applied to expose seeds to nine osmotic water potentials ranging from soil water saturation (0 MPa) and field capacity (-.01 to -.03 MPa) to the permanent wilting point (-1.5 MPa). We measured germinability (number of germinated seeds relative to total number of seeds per lot) and mean germination time (mean time required for maximum germination of a seed lot) to quantify germination. Based on the empirical data of the germination we estimated the parameters of the hydrotime model which simulates timing and success of seed emergence. Our findings indicate that Brigalow seeds are remarkably tolerant to water stress, with germination being observed at a water potential as low as -1.5 MPa. Likewise, the average base water potential of a seed population (hydrotime model) was very low and ranged between -1.533 and -1.451 MPa. In general, Brigalow seeds germinate opportunistically over a broad range of abiotic conditions related to temperature, salinity, and water availability. Direct seeding and germination of native plants on post-mining land may be an effective and economically viable solution in order to re-establish plant communities. However, due to their capacity to reproduce asexually, alternative rehabilitation approaches such as transplantation of whole soil-root compartments may become attractive for restoration ecologists to achieve safe, stable, and non-polluting ecosystems. PMID:24795847

Arnold, Sven; Kailichova, Yolana; Baumgartl, Thomas

2014-01-01

321

Effect of herbicide Imazethapyr (pursuit™) on chickpea seed germination  

Microsoft Academic Search

Herbicides are the most successful weed control technology ever developed. To assess the effects of herbicides on non-target plants, a study was carried out by using Imazethapyr (IM) on JG-11 cultivar of chickpea germination and early growth. Hydroponic conditions with five concentrations (0.5, 1, 2.5, 5, and 10 ppm) of IM were employed along with control. On the termination day

Manijeh Hoseiny-Rad; Shobha Jagannath

2011-01-01

322

Transient Occurrence of Seed Germination Processes during Coffee Postharvest Treatment  

Microsoft Academic Search

Background and Aims: The chemical composition of green coffee and thus the final coffee quality are specifically determined by the mode of post-harvest treatment, i.e. the wet and dry processing. Recently, it was shown that metabolic processes, i.e. germination and, a slightly delayed stress-related metabolism are executed during the course of processing. The specific ambient conditions of either post-harvest treatment

G. Bytof; S.-E. Knopp; D. Kramer; B. Breitenstein; J. H. W. Bergervoet; S. P. C. Groot; D. Selmar

2007-01-01

323

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

PubMed

The mechanisms imposing a gibberellin (GA) requirement to promote the germination of dormant and non-dormant Arabidopsis seeds were analyzed using the GA-deficient mutant ga1, several seed coat pigmentation and structure mutants, and the abscisic acid (ABA)-deficient mutant aba1. Testa mutants, which exhibit reduced seed dormancy, were not resistant to GA biosynthesis inhibitors such as tetcyclacis and paclobutrazol, contrarily to what was found before for other non-dormant mutants in Arabidopsis. However, testa mutants were more sensitive to exogenous GAs than the wild-types in the presence of the inhibitors or when transferred to a GA-deficient background. The germination capacity of the ga1-1 mutant could be integrally restored, without the help of exogenous GAs, by removing the envelopes or by transferring the mutation to a tt background (tt4 and ttg1). The double mutants still required light and chilling for dormancy breaking, which may indicate that both agents can have an effect independently of GA biosynthesis. The ABA biosynthesis inhibitor norflurazon was partially efficient in releasing the dormancy of wild-type and mutant seeds. These results suggest that GAs are required to overcome the germination constraints imposed both by the seed coat and ABA-related embryo dormancy. PMID:10677434

Debeaujon, I; Koornneef, M

2000-02-01

324

[Study on germination rate of zoysia (Zoysia japonica Steud.) seeds using near infrared reflectance spectroscopy].  

PubMed

With 37 zoysia seed samples with different germination rates ranging from 58.5% to 92%, harvested in different years from 2009 to 2011 and from different locations of China, a model for determining germination rate of zoysia seeds was tried to be built by near infrared reflectance spectroscopy with quantitative partial least squares (QPLS). All the seeds samples were divided into two groups: calibration set (including 28 samples) and validation set (including 9 samples). The results showed that with the spectral range from 6 000 to 7 000 cm(-1) and 6 main components, there was a better fitting between the predictive value and true value. Determination coefficients (R2) of calibration and validation sets are 90.73% and 91.80%, the coefficients of correlation are 0.986 6 and 0.987 2, the standard errors are 9.80 and 9.47, and the average absolute errors are 7.64% and 6.98% respectively. Even with different calibration samples, the models have a high determination coefficient (R2 over building of NIR model for determining 90%), low standard errors (about 10.00) and low absolute errors (about 8.00%). The building of NIR model for determining germination rate of zoysia seeds could promote the application of high quality seeds in production. PMID:24409708

Liang, Xiao-Hong; Zhang, Li-Juan; Fan, Bo; Mao, Wen-Hua; Mao, Wen-Hua; Puyang, Xue-Hua; Han, Lie-Bao

2013-10-01

325

Abscisic acid (ABA) sensitivity regulates desiccation tolerance in germinated Arabidopsis seeds.  

PubMed

During germination, orthodox seeds lose their desiccation tolerance (DT) and become sensitive to extreme drying. Yet, DT can be rescued, in a well-defined developmental window, by the application of a mild osmotic stress before dehydration. A role for abscisic acid (ABA) has been implicated in this stress response and in DT re-establishment. However, the path from the sensing of an osmotic cue and its signaling to DT re-establishment is still largely unknown. Analyses of DT, ABA sensitivity, ABA content and gene expression were performed in desiccation-sensitive (DS) and desiccation-tolerant Arabidopsis thaliana seeds. Furthermore, loss and re-establishment of DT in germinated Arabidopsis seeds was studied in ABA-deficient and ABA-insensitive mutants. We demonstrate that the developmental window in which DT can be re-established correlates strongly with the window in which ABA sensitivity is still present. Using ABA biosynthesis and signaling mutants, we show that this hormone plays a key role in DT re-establishment. Surprisingly, re-establishment of DT depends on the modulation of ABA sensitivity rather than enhanced ABA content. In addition, the evaluation of several ABA-insensitive mutants, which can still produce normal desiccation-tolerant seeds, but are impaired in the re-establishment of DT, shows that the acquisition of DT during seed development is genetically different from its re-establishment during germination. PMID:24697728

Maia, Julio; Dekkers, Bas J W; Dolle, Miranda J; Ligterink, Wilco; Hilhorst, Henk W M

2014-07-01

326

Germination of pine seed in weightlessness (investigation in Kosmos 782)  

NASA Technical Reports Server (NTRS)

An investigation was made of the orientation of aboveground and underground organs of pine plants grown from seed in weightlessness. Orientation was found to be caused by the position of the seeds relative to the substrate surface. Normal growth was manifest only for the plants grown from seed oriented with embryo toward the substrate. Differences were noted between experiment and control as to the quantitative content of nucleoli in the meristematic cells of the rootlets and the shape of cells in the cotyledonous leaflets. No complete agreement was found between data obtained in weightlessness and when gravity was compensated (clinostat treatment with horizontal rotation).

Platonova, R. N.; Parfenov, G. P.; Olkhovenko, V. P.; Karpova, N. I.; Pichugov, M. Y.

1978-01-01

327

The effect of ethylene, octanoic acid and a plant-derived smoke extract on the germination of light-sensitive lettuce seeds  

Microsoft Academic Search

The effects of an aqueous plant-derived smoke extract, octanoic acid and ethylene on germination of light-sensitive Grand Rapids lettuce seeds were investigated. The smoke extract brought about a concentration dependent increase in germination and a complete inhibition of germination at high concentrations. Octanoic acid could not induce germination. Ethylene at concentrations over 5 µL L-1 increased lettuce seed germination, but

A. K. Jäger; A. Strydom; J. Staden

1996-01-01

328

The role of the Arabidopsis FUSCA3 transcription factor during inhibition of seed germination at high temperature  

PubMed Central

Background Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3) is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. Results In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP) during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. Conclusion In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying germination at supraoptimal temperature. Physiologically, this is important since delaying germination has a protective role at high temperature. Transcriptomic analysis of seeds imbibed at supraoptimal temperature reveal that a complex program is in place, which involves not only the regulation of heat and dehydration response genes to adjust cellular functions, but also the activation of seed-specific programs and the inhibition of germination-promoting programs to delay germination.

2012-01-01

329

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

PubMed

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

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

2012-10-01

330

Effect of cold stratification treatments on germination of drought tolerant shrubs seeds.  

PubMed

This study was carried out to determine effects of different durations (20, 40, 60 days and control) of cold stratification treatments on seed germination and to overcome dormancy in seeds of twelve different drought tolerant plants. The species used in this study were Arbutus andrachne L., Cistus creticus L., Colutea armena Bois. Huet., Cotinus coggygria Scop., Cotoneaster numullaria Fisch. and Mey, Elaeagnus angustifolia L., Jasminum fruticans L., Paliurus spina-christii Mill., Punica granatum L., Pyracantha coccinea Roem., Rhus coriaria L., and Ziziphus jujuba Mill. The seeds were sown in polyethylene pots under greenhouse and on seedbeds under open field conditions. Statistical design was a randomized complete block design with three replications. Germinated seeds were counted and observed periodically for 90 days after sowing to determine germination percentages (GP) and germination rates (GR). While the highest GP were determined according to duration of cold stratification under greenhouse conditions for each species were 44.2% for 60 days, 2.5% for 20 days, 85.6% for 60 days, 13.5% for 20 and 60 days, 64.3% for 20 days, 11.2% for 60 days, 8.2% for 20 days and 14.1% for 20 days for Cotinus coggygria, Cotoneaster numullaria, Jasminum fruticans, Paliurus spina-christii, Pyracantha coccinea, Punica granatum, Rhus coriaria and Ziziphus jujuba respectively The highest GP were 16.5% forArbutus andrachne and 91.3% for Colutea armena for 20 days cold stratified seeds and sown under open field conditions. Furthermore, the highest GP were obtained from seeds of Cistus creticus (27.5%) and Elaeagnus angustifolia (56.2%) in control sowing. PMID:17929764

Olmez, Zafer; Temel, Fatih; Gokturk, Askin; Yahyaoglu, Zeki

2007-04-01

331

Germination and storage characteristics of Prunus africana seeds  

Microsoft Academic Search

Prunus africana, from the moist highlands of sub-Saharan Africa, is subject to great exploitation because its bark is used in the treatment of prostate-related diseases. A better understanding of the biology of its seed could help the ex situ and in situ conservation of the species. Fifty per cent of fresh seeds (46.8% MC) from mature purple fruits harvested in

M. Sacandé; H. W. Pritchard; A. E. Dudley

2004-01-01

332

Germination behaviour of seeds of the New Zealand woody species Alseuosmia macrophylla, A. pusilla, Cordyline banksii, Geniostoma rupestre, Myrtus bullata, and Solanum aviculare  

Microsoft Academic Search

Seeds from freshly collected fruit were tested to examine germination period in relation to season, germination rates, and degree of success, in conditions similar to those that they could experience after dispersal in nature. In a relatively well lit, moist treatment seeds germinated in autumn?winter, or winter?spring(?summer). Germination of a few Alseuosmia macrophylla seeds was delayed until spring of the

C. J. Burrows

1999-01-01

333

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

NASA Technical Reports Server (NTRS)

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

Wahid, Nadya; Bounoua, Lahouari

2011-01-01

334

Reduced germination of Orobanche cumana seeds in the presence of Arbuscular Mycorrhizal fungi or their exudates.  

PubMed

Broomrapes (Orobanche and Phelipanche spp) are parasitic plants responsible for important crop losses, and efficient procedures to control these pests are scarce. Biological control is one of the possible strategies to tackle these pests. Arbuscular Mycorrhizal (AM) fungi are widespread soil microorganisms that live symbiotically with the roots of most plant species, and they have already been tested on sorghum for their ability to reduce infestation by witchweeds, another kind of parasitic plants. In this work AM fungi were evaluated as potential biocontrol agents against Orobanche cumana, a broomrape species that specifically attacks sunflower. When inoculated simultaneously with O. cumana seeds, AM fungi could offer a moderate level of protection against the broomrape. Interestingly, this protection did not only rely on a reduced production of parasitic seed germination stimulants, as was proposed in previous studies. Rather, mycorrhizal root exudates had a negative impact on the germination of O. cumana induced by germination stimulants. A similar effect could be obtained with AM spore exudates, establishing the fungal origin of at least part of the active compounds. Together, our results demonstrate that AM fungi themselves can lead to a reduced rate of parasitic seed germination, in addition to possible effects mediated by the mycorrhizal plant. Combined with the other benefits of AM symbiosis, these effects make AM fungi an attractive option for biological control of O. cumana. PMID:23145139

Louarn, Johann; Carbonne, Francis; Delavault, Philippe; Bécard, Guillaume; Rochange, Soizic

2012-01-01

335

Transient Occurrence of Seed Germination Processes during Coffee Post-harvest Treatment  

PubMed Central

Background and Aims The chemical composition of green coffee and thus the final coffee quality are specifically determined by the mode of post-harvest treatment, i.e. the wet and dry processing. Recently, it was shown that metabolic processes, i.e. germination and, a slightly delayed stress-related metabolism are executed during the course of processing. The specific ambient conditions of either post-harvest treatment may influence differentially the extent and time course of these metabolic reactions; therefore, the incidence and intensity of germination processes in coffee seeds were analysed during processing. Methods Expression of the germination-specific isocitrate lyase was monitored using competitive RT-PCRs analyses. Resumption of cell cycle activity and cell division were determined by flow cytometry, as well as by the abundance of ?-tubulin quantified by Western blot analyses. Key Results The extent and the time courses of germination processes in coffee seeds differed significantly between wet and dry processed beans. The highest germination activity occurred 2 d after the onset of wet processing, whereas the corresponding maximum in the course of dry processing appeared about 1 week after the start of post harvest treatment. Conclusions As recently shown, there are specific differences in the chemical composition of differentially processed coffee beans. It is concluded that these substantial differences are the consequence of the differential expression of germination processes, i.e. they are the result of differences in the corresponding metabolic activities. The coherence of germination-related metabolism and of expression-specific coffee qualities establishes the basis for a novel approach in coffee research.

Bytof, Gerhard; Knopp, Sven-Erik; Kramer, Daniela; Breitenstein, Bjorn; Bergervoet, Jan H. W.; Groot, Steven P. C.; Selmar, Dirk

2007-01-01

336

Germination responses of the invasive Calotropis procera (Ait.) R. Br. (Apocynaceae): comparisons with seeds from two ecosystems in Northeastern Brazil.  

PubMed

Life history traits are considered key indicators of plant invasibility. Among them, the germination behavior of seeds is of major relevance because it is influenced by environmental factors of invaded ecosystem. Here, we investigated how seed traits and seed tolerance to environmental factors on seed germination of Calotropis procera vary depending on the invaded ecosystems in northeastern Brazil. We have tested seeds from two vegetation types - Caatinga and Restinga - to different levels of light intensity, salinity, and water stress. Previous to those experiments, seed-set and morphometric analysis were carried out for both studied populations. We have observed a higher seed-set in Caatinga. Seeds produced in this ecosystem had lower seed moisture content. Seeds from Restinga showed lower germination time when light intensity decreased. We observed a reduction in both the germinability and the synchronization index with decreasing osmotic potential and increasing salinity. Nevertheless, both populations exhibited changes in photoblastism when seeds were submitted to water and saline stress. In conclusion, C. procera seeds are tolerant to environmental factors assessed. That characteristic ensures the colonization success and wide distribution of this plant species in the studied ecosystems. PMID:24068090

Leal, Laura C; Meiado, Marcos V; Lopes, Ariadna V; Leal, Inara R

2013-09-01

337

Is reduced seed germination due to water limitation a special survival strategy used by xerophytes in arid dunes?  

Microsoft Academic Search

Using multi-sampling methods, seeds of xerophytic species, Caragana korshinskii, Artemisia sphaerocephala, and Hedysarum scoparium were collected from semi-arid regions of northwest China, while those of Reaumuria soongorica and Zygophyllum xanthoxylum were harvested from arid regions. Seed germination in these five species was studied under water limiting conditions, imposed by increasing concentrations of polyethylene glycol (PEG 6000). Seeds of C. korshinskii,

Yan Jun Zeng; Yan Rong Wang; Ju Ming Zhang

2010-01-01

338

The effects of small-scale environmental heterogeneity on seed germination in experimental treefall gaps in New Zealand  

Microsoft Academic Search

Seed germination of woody species was studied in treefall gaps in New Zealand to assess how environmental heterogeneity affects regeneration from seed. Gaps were created in a relictual Pinus radiata plantation destined for restoration to native forest. Seeds of the native species Alectryon excelsus, Macropiper excelsum, and Fuch- sia excorticata, and the invasive alien species Cytisus scoparius and Berberis darwinii

Kate G. McAlpine; Donald R. Drake

2002-01-01

339

Variation in Seed Germination of 134 Common Species on the Eastern Tibetan Plateau: Phylogenetic, Life History and Environmental Correlates  

PubMed Central

Seed germination is a crucial stage in the life history of a species because it represents the pathway from adult to offspring, and it can affect the distribution and abundance of species in communities. In this study, we examined the effects of phylogenetic, life history and environmental factors on seed germination of 134 common species from an alpine/subalpine meadow on the eastern Tibetan Plateau. In one-way ANOVAs, phylogenetic groups (at or above order) explained 13.0% and 25.9% of the variance in germination percentage and mean germination time, respectively; life history attributes, such as seed size, dispersal mode, explained 3.7%, 2.1% of the variance in germination percentage and 6.3%, 8.7% of the variance in mean germination time, respectively; the environmental factors temperature and habitat explained 4.7%, 1.0% of the variance in germination percentage and 13.5%, 1.7% of the variance in mean germination time, respectively. Our results demonstrated that elevated temperature would lead to a significant increase in germination percentage and an accelerated germination. Multi-factorial ANOVAs showed that the three major factors contributing to differences in germination percentage and mean germination time in this alpine/subalpine meadow were phylogenetic attributes, temperature and seed size (explained 10.5%, 4.7% and 1.4% of the variance in germination percentage independently, respectively; and explained 14.9%, 13.5% and 2.7% of the variance in mean germination time independently, respectively). In addition, there were strong associations between phylogenetic group and life history attributes, and between life history attributes and environmental factors. Therefore, germination variation are constrained mainly by phylogenetic inertia in a community, and seed germination variation correlated with phylogeny is also associated with life history attributes, suggesting a role of niche adaptation in the conservation of germination variation within lineages. Meanwhile, selection can maintain the association between germination behavior and the environmental conditions within a lineage.

Xu, Jing; Li, Wenlong; Zhang, Chunhui; Liu, Wei; Du, Guozhen

2014-01-01

340

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

PubMed

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 temperate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function of mycorrhizal fungi in Vanilla, a pantropical genus that is both terrestrial and epiphytic. Mycorrhizal roots were collected from four Vanilla species in Puerto Rico, Costa Rica and Cuba. Cultured and uncultured mycorrhizal fungi were identified by sequencing the internal transcribed spacer region of nuclear rDNA (nrITS) and part of the mitochondrial ribosomal large subunit (mtLSU), and by counting number of nuclei in hyphae. Vanilla spp. were associated with a wide range of mycorrhizal fungi: Ceratobasidium, Thanatephorus and Tulasnella. Related fungi were found in different species of Vanilla, although at different relative frequencies. Ceratobasidium was more common in roots in soil and Tulasnella was more common in roots on tree bark, but several clades of fungi included strains from both substrates. Relative frequencies of genera of mycorrhizal fungi differed significantly between cultured fungi and those detected by direct amplification. Ceratobasidium and Tulasnella were tested for effects on seed germination of Vanilla and effects on growth of Vanilla and Dendrobium plants. We found significant differences among fungi in effects on seed germination and plant growth. Effects of mycorrhizal fungi on Vanilla and Dendrobium were similar: a clade of Ceratobasidium had a consistently positive effect on plant growth and seed germination. This clade has potential use in germination and propagation of orchids. Results confirmed that a single orchid species can be associated with several mycorrhizal fungi with different functional consequences for the plant. PMID:18065002

Porras-Alfaro, Andrea; Bayman, Paul

2007-01-01

341

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

PubMed Central

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.

Wang, Wenyi; Xu, Mengyun; Wang, Ya

2014-01-01

342

Effects of different doses of low power continuous wave he-ne laser radiation on some seed thermodynamic and germination parameters, and potential enzymes involved in seed germination of sunflower (Helianthus annuus L.).  

PubMed

In this study, water-soaked seeds of sunflower were exposed to He-Ne laser irradiation of different energies to determine whether or not He-Ne laser irradiation caused changes to seed thermodynamic and germination parameters as well as effects on the activities of germination enzymes. The experiment comprised four energy levels: 0 (control), 100, 300 and 500mJ of laser energy and each treatment replicated four times arranged in a completely randomized design. The experimentation was performed under the greenhouse conditions in the net-house of the Department of Botany, University of Agriculture, Faisalabad. The seed thermodynamic parameters were calculated according to seed germination thermograms determined with a calorimeter at 25.8°C for 72h. Various thermodynamic parameters of seed (?H, (?S)(e), (?S)(c), (?S)(e) /?t and (?S)(c) /?t) were affected significantly due to presowing laser treatment. Significant changes in seed germination parameters and enzyme activities were observed in seeds treated with He-Ne laser. The He-Ne laser seed treatment resulted in increased activities of amylase and protease. These results indicate that the low power continuous wave He-Ne laser light seed treatment has considerable biological effects on seed metabolism. This seed treatment technique can be potentially employed to enhance agricultural productivity. PMID:20670360

Perveen, Rashida; Ali, Qasim; Ashraf, Muhammad; Al-Qurainy, Fahad; Jamil, Yasir; Raza Ahmad, Muhammad

2010-01-01

343

Effects of nitrification inhibitors on germination of various seeds in soil  

Microsoft Academic Search

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

J. M. Bremner; M. J. Krogmeier

1989-01-01

344

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

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.

Foster, M.S.

2008-01-01

345

Stress induction and antimicrobial properties of a lipid transfer protein in germinating sunflower seeds.  

PubMed

Nonspecific lipid transfer proteins (nsLTPs) belong to a large family of plant proteins whose function in vivo remains unknown. In this research, we studied a LTP previously isolated from sunflower seeds (Ha-AP10), which displays strong antimicrobial activity against a model fungus. The protein is present during at least the first 5 days of germination, and tissue printing experiments revealed the homogeneous distribution of the protein in the cotyledons. Here we report that Ha-AP10 exerts a weak inhibitory effect on the growth of Alternaria alternata, a fungus that naturally attacks sunflower seeds. These data put into question the contribution of Ha-AP10 as an antimicrobial protein of direct effect on pathogenic fungus, and rather suggest a function related to the mobilization of lipid reserves. We also show that the levels of Ha-AP10 in germinating seeds increase upon salt stress, fungal infection and ABA treatment, indicating that it somehow participates in the adaptative responses of germinating sunflower seeds. PMID:16008084

Gonorazky, Ana G; Regente, Mariana C; de la Canal, Laura

2005-06-01

346

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

PubMed Central

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

Schonbeck, Mark W.; Egley, Grant H.

1980-01-01

347

The re-establishment of desiccation tolerance in germinated Arabidopsis thaliana seeds and its associated transcriptome.  

PubMed

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 seeds in a polyethylene glycol (PEG) solution re-induces the mechanisms necessary for expression of DT. Based on a SNP-tile array gene expression profile, our data indicates that the re-establishment of DT, in this system, is related to a programmed reversion from a metabolic active to a quiescent state similar to prior to germination. Our findings show that transcripts of germinated seeds after the PEG-treatment are dominated by those encoding LEA, seed storage and dormancy related proteins. On the other hand, a massive repression of genes belonging to many other classes such as photosynthesis, cell wall modification and energy metabolism occurs in parallel. Furthermore, comparison with a similar system for Medicago truncatula reveals a significant overlap between the two transcriptomes. Such overlap may highlight core mechanisms and key regulators of the trait DT. Taking into account the availability of the many genetic and molecular resources for Arabidopsis, the described system may prove useful for unraveling DT in higher plants. PMID:22195004

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

2011-01-01

348

Antioxidant activity and inhibition of lipid peroxidation in germinating seeds of transgenic soybean expressing OsHGGT.  

PubMed

Tocochromanols are potent lipid-soluble antioxidants and essential nutrients for human health. Genetic engineering techniques were used to develop soybeans with enhanced vitamin E levels, including tocotrienols, which are not found in soybean. The gene encoding rice homogentisate geranylgeranyl transferase (HGGT) was overexpressed in soybeans using seed-specific and constitutive promoters. The association between abundance of vitamin E isomers and antioxidant activity was investigated during seed germination. With the exception of ?-tocotrienol, all vitamin E isomers were detected in germinating seeds expressing OsHGGT. The antioxidant properties of germinating seed extracts were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals and lipid peroxidation (TBARS). Compared with intact wild-type seeds, transgenic seeds showed increases in radical scavenging of 5.4-17 and 23.2-35.3% in the DPPH and ABTS assays, respectively. Furthermore, the lipid peroxidation levels were 2.0-4.5-fold lower in germinating seeds from transgenic lines than in wild-type seeds. Therefore, it appears that the antioxidant potential of transgenic oil-producing plants such as soybean, sunflower, and corn may be enhanced by overexpressing OsHGGT during seed germination. PMID:21175184

Kim, Yul Ho; Lee, Yu Young; Kim, Yong Ho; Choi, Man Soo; Jeong, Kwang Ho; Lee, Seuk Ki; Seo, Min Jung; Yun, Hong Tai; Lee, Choon Ki; Kim, Wook Han; Lee, Sang Chul; Park, Soon Ki; Park, Hyang Mi

2011-01-26

349

Della proteins and gibberellin-regulated seed germination and floral development in Arabidopsis.  

PubMed

RGA (repressor of ga1-3) and GAI (gibberellin insensitive) are negative regulators of plant hormone gibberellin (GA) signaling in Arabidopsis. The GA-deficient mutant ga1-3 is a nongerminating, extreme dwarf that flowers late and produces male-sterile flowers. The rga and gai null alleles interact synergistically to rescue vegetative growth and floral initiation in ga1-3, indicating that RGA and GAI are major repressors for these processes. However, rga and gai in combination cannot rescue seed germination or floral development in ga1-3. RGA and GAI belong to the DELLA subfamily within the GRAS family of plant regulatory proteins. Three additional DELLA proteins RGL1, RGL2, and RGL3 are present in Arabidopsis. Previous studies provided evidence that RGL2 and possibly RGL1 control seed germination. To investigate further the function of the RGL genes, we examined the expression profiles of all 5 DELLA protein genes by real-time PCR. RGA and, to a lesser extent, GAI mRNAs were expressed ubiquitously in all tissues, whereas RGL1, 2, and 3 transcripts were present at high levels only in germinating seeds and/or flowers and siliques. Using the newly isolated rgl1, rgl2, and rgl3 T-DNA insertion mutants, we demonstrated that RGL2 is the major repressor in seed germination. We further provided evidence that RGA, RGL1, and RGL2 are all involved in modulating floral development. Interestingly, RGL2 expression is regulated not only at the transcript level. We showed that RGL2 protein in imbibed seeds is rapidly degraded by GA treatment and that the F-box protein SLY1 is required for RGL2 degradation to occur. PMID:15173565

Tyler, Ludmila; Thomas, Stephen G; Hu, Jianhong; Dill, Alyssa; Alonso, Jose M; Ecker, Joseph R; Sun, Tai-Ping

2004-06-01

350

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

PubMed Central

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

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

2008-01-01

351

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

PubMed

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

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

2005-06-01

352

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

PubMed Central

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.

Ren, Chengwei; Kermode, Allison R.

2000-01-01

353

Volatile and gaseous metabolites released by germinating seeds of lentil and maize cultivars with different susceptibilities to fusariosis and smut  

Microsoft Academic Search

The effect of volatile and gaseous metabolites released by germinating seeds of lentil cultivars more and less susceptible\\u000a to fusariosis on the germination of spores ofMucor racemosus, Trichoderma viride, Verticillium dahliae andBotrytis cinerea was found to depend rather on the fungal genus than on the lentil cultivar. However, spores ofFusarium oxysporum reacted more sensitively during germination to the presence of

V. ?atská; V. Van?ura

1980-01-01

354

Effect of Light and Moisture Conditions and Seed Age on Germination of Three Closely Related Myosotis Species  

Microsoft Academic Search

Germination of three closely related species from the Myosotis palustris group (M. nemorosa, M. palustris subsp. laxiflora, M. caespitosa) differing in their habitats and capacity for clonal growth, was compared in two greenhouse experiments. To evaluate both\\u000a inter- and intraspecific variation, each species was represented by seeds from several populations. Final germination percentage\\u000a and germination rates T50 were compared both

Eva Koutecká; Jan Lepš

2009-01-01

355

Seed germination and seedling survival traits of invasive and non-invasive congeneric Ruellia species (Acanthaceae) in Yucatan, Mexico  

Microsoft Academic Search

We compared requirements for seed germination and seedling establishment for Ruellia nudiflora, an invasive species in Yucatan, Mexico with those of the congeneric non-invasive R. pereducta. Germination and seedling survival rates were higher for R. nudiflora than for R. pereducta under high light. Additionally, the ranges of temperature and water potential that allow germination for R. nudiflora were much broader than those of R. pereducta.

J. Carlos Cervera; Víctor Parra-Tabla

2009-01-01

356

Germination response of Hylocereus setaceus (Salm-Dyck ex DC: ) Ralf Bauer (Cactaceae) seeds to temperature and reduced water potentials.  

PubMed

The germination response of Hylocereus setaceus seeds to isothermic incubation at different water potentials was analysed by using the thermal time and hydrotime models, aiming to describe some germination parameters of the population and to test the validity of the models to describe the response of the seeds to temperature and water potential. Hylocereus setaceus seeds germinated relatively well in a wide range of temperatures and the germination was rate limited from 11 to 20 degrees C interval and beyond 30 degrees C until 40 degrees C, in which the germination rate respectively shifts positively and negatively with temperature. The minimum or base temperature (T(b)) for the germination of H. setaceus was 7 degrees C, and the ceiling temperature varied nearly from 43.5 to 59 degrees C depending on the percent fraction, with median set on 49.8 degrees C. The number of degrees day necessary for 50% of the seeds to germinate in the infra-optimum temperature range was 39.3 degrees C day, whereas at the supra-optimum interval the value of theta = 77 was assumed to be constant throughout. Germination was sensitive to decreasing values of psi in the medium, and both the germinability and the germination rate shift negatively with the reduction of psi, but the rate of reduction changed with temperature. The values of base water potential (psi(b)) shift to zero with increasing temperatures and such variation reflects in the relatively greater effect of low psi on germination in supra optimum range of T. In general, the model described better the germination time courses at lower than at higher water potentials. The analysis also suggest that Tb may not be independent of psi and that psi(b(g)) may change as a function of temperature at the infra-otimum temperature range. PMID:20231970

Simão, E; Takaki, M; Cardoso, V J M

2010-02-01

357

Differentiation of seed germination traits in relation to the natural habitats of three Ulmus species in Japan  

Microsoft Academic Search

Germination traits of three Japanese Ulmus species, including two summer-fruiting species, U. davidiana var. japonica (UD) and U. laciniata (UL), and an autumn-fruiting species, U. parvifolia (UP), were investigated. Germination tests that controlled light (16 h dark–8 h light\\/24 h dark) and temperature (alternating\\u000a 20–30°C\\/constant 23°C) conditions were conducted just after seed dissemination. Under the preferred (light and alternating\\u000a temperature) conditions, UD germinated

Haruto Nomiya

2010-01-01

358

Transfection of germinating barley seed electrophoretically with exogenous DNA.  

PubMed

A method is described for transfection (genetic transformation) of barley caryopsis electrophoretically with DNA. ?-Glucuronidase activity was detected after the electrophoretic transfection with plasmid pBI221 DNA carrying the cauliflower mosaic virus promotor and bacterial ?-glucuronidase coding sequence. Electrophoretic transfection is evidently effective with pieces of callus and seeds of many plants. PMID:24232711

Ahokas, H

1989-04-01

359

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

Microsoft Academic Search

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

Xu He; Allison R. Kermode

2003-01-01

360

Seed dormancy and germination: the role of abscisic acid and gibberellins and the importance of hormone mutants  

Microsoft Academic Search

Over the past decades many studies have aimed at elucidating the regulation of seed dormancy and germination. Many hypotheses have been proposed and rejected but the regulatory principle behind changes in dormancy and induction of germination is still a ‘black’ box. The majority of proposed mechanisms have a role for certain plant hormones in common. Abscisic acid and the gibberellins

H. W. M. Hilhorst; C. M. Karssen

1992-01-01

361

Changes in anti-nutritional factors in Indian bean (Dolichos lablab L.) seeds during germination and their behaviour during cooking  

Microsoft Academic Search

Purpose – This paper aims to study the changes in anti-nutritional factors during the germination of the Indian bean and also to carryout an evaluation by subjecting it to different cooking treatments – boiling, roasting and pressure cooking. Design\\/methodology\\/approach – The healthy Indian bean (Dolichos lablab L.) seeds were soaked for 12 h and allowed to germinate (sprout) at room

V. Ramakrishna; P. Jhansi Rani; P. Ramakrishna Rao

2008-01-01

362

Use of immature seed germination technique as an alternative to in vitro culture of sunflower (Helianthus annuus L.) embryos  

Microsoft Academic Search

The importance of developing new techniques that would simplify the complexity and operative costs of genetic breeding plans has been widely recognized. In that sense, germination from immature seeds in sunflower is a simpler and cheaper alternative to that of in vitro embryo culture, as it is produced in non-sterile conditions. Different techniques to maximize germination percentage were tested using

Adriana Torresfin; Juan Kesteloot; Fernando Castaño; Raúl Rodríguez; Mabel Colabelli

1996-01-01

363

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

PubMed Central

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

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

2011-01-01

364

Phenolic profile and antioxidant activity in selected seeds and sprouts.  

PubMed

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

Paj?k, Paulina; Socha, Robert; Ga?kowska, Dorota; Ro?nowski, Jacek; Fortuna, Teresa

2014-01-15

365

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

Microsoft Academic Search

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

Lihong Wang; Xiaohua Huang; Qing Zhou

2008-01-01

366

Cowpea ribonuclease: properties and effect of NaCl-salinity on its activation during seed germination and seedling establishment  

Microsoft Academic Search

Pitiúba cowpea [Vigna unguiculata (L.) Walp] seeds were germinated in distilled water (control treatment) or in 100 mM NaCl solution (salt treatment), and\\u000a RNase was purified from different parts of the seedlings. Seedling growth was reduced by the NaCl treatment. RNase activity\\u000a was low in cotyledons of quiescent seeds, but the enzyme was activated during germination and seedling establishment. Salinity\\u000a reduced

Enéas Gomes-Filho; Carmen Rogélia Farias Machado Lima; José Hélio Costa; Ana Cláudia Marinho da Silva; Maria da Guia Silva Lima; Claudivan Feitosa de Lacerda; José Tarquinio Prisco

2008-01-01

367

A membrane-bound NAC transcription factor NTL8 regulates gibberellic acid-mediated salt signaling in Arabidopsis seed germination  

Microsoft Academic Search

Summary Gibberellic acid (GA) plays a key role in seed germination through coordinate interactions with other growth hormones and external signals. However, the way in which external signals are incorporated into the GA-signaling pathway is largely unknown. Here, we demonstrate that a membrane-bound NAC transcription factor NTL8 mediates the salt regulation of seed germination via the GA pathway, primarily independently

Sang-Gyu Kim; An-Kyo Lee; Hye-Kyung Yoon; Chung-Mo Park

2008-01-01

368

Seed germination and seedling establishment of Neotropical dry forest species in response to temperature and light conditions  

Microsoft Academic Search

A study was conducted to examine the germination requirements of Cedrela odorata, Guaiacum sanctum and Calycophyllum candidissimum seeds, and the effect of light intensity on survival and growth of C. odorata and G. sanctum seedlings planted on open, partially-open and beneath the canopy of a dry forest in Nicaragua. The results show that germination\\u000a of C. candidissimum seeds was significantly

Benigno González-Rivas; Mulualem Tigabu; Guillermo Castro-Marín; Per Christer Odén

2009-01-01

369

Seed characteristics and soil surface patch type interact to affect germination of semi-arid woodland species  

Microsoft Academic Search

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

Amber L. Briggs; John W. Morgan

2011-01-01

370

Purification of a non-histone protein with properties of antizyme to ornithine decarboxylase from germinated barley seeds  

Microsoft Academic Search

The purification of a chromatin-bound antizyme to ornithine decarboxylase from germinated barley seeds is described. This antizyme was extracted from chromatin by 2 M NaCl and purified to homogeneity. Its molecular weight was found to be 9000 with an isoelectric point of 4.1. It reacts with both cytosolic and chromatinbound ornithine decarboxylase from germinated barley seeds and E. coli, but

Christos A. Panagiotidis; Dimitrios A. Kyriakidis

1985-01-01

371

Cadmium stress affects seed germination and seedling growth in Sorghum bicolor (L.) Moench by changing the activities of hydrolyzing enzymes  

Microsoft Academic Search

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

Saritha V. Kuriakose; M. N. V. Prasad

2008-01-01

372

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

PubMed

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

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

2013-10-16

373

The Role of Hormones during Seed Development and Germination  

Microsoft Academic Search

\\u000a Seed production1 is an extraordinary adaptation to a terrestrial environment that permits plants to reproduce under dry conditions and broadly\\u000a disperse their progeny, which can then survive in an arrested state until environmental conditions favor growth of the next\\u000a generation. Although there are many anecdotal reports of extreme longevity (6), the current record for documented viability\\u000a is over 1000 years

Ruth R. Finkelstein

374

Seed germination and life history syndromes in the California chaparral  

Microsoft Academic Search

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

Jon E. Keeley

1991-01-01

375

Soil water availability effects on seed germination account for species segregation in semiarid roadslopes  

Microsoft Academic Search

Previous studies report that the low colonisation success on eroded roadslopes of semiarid environments is controlled by microsite\\u000a limitations. We predicted that soil water availability, through its effect on seed germination, is a determinant factor in\\u000a the colonisation process of roadslopes in semiarid environments. Moreover, we predicted that the success of species establishment\\u000a on the harshest roadslope conditions (i.e., south-facing

Esther Bochet; Patricio García-Fayos; Beatriz Alborch; Jaume Tormo

2007-01-01

376

Avian consumption and seed germination of the hemiparasitic mistletoe Agelanthus natalitius (Loranthaceae)  

Microsoft Academic Search

We documented avian consumers of the mistletoe Agelanthus natalitius in the field and quantified their effects on seed germination in captive studies. Seven bird species were frequently observed\\u000a to feed on mistletoe fruits in the field, namely Cape Batis (Batis capensis), Cape White-eye (Zosterops virens), Red-fronted Tinkerbird (Pogoniulus pusillus), Red-winged Starling (Onychognathus morio), Dark-capped Bulbul (Pycnonotus tricolor), Speckled Mousebird (Colius

D. Y. Okubamichael; M. Z. Rasheed; M. E. Griffiths; D. Ward

2011-01-01

377

[Stimulatory effects of low temperature treatment of germinating seeds on flower-bud differentiation in broccoli].  

PubMed

The effects of low temperature treatment (0-2 degrees C) of germinating seeds in accelerating process of flower-bud differentiation in broccoli (Brassica oleracea var. italica) were studied. The results indicated that low temperature treatment of germinating seeds for 10 d in broccoli (T(10)) lowered 0.86 nodes and advanced 5 d for the critical stage of flower-bud differentiation, stage of primary furcation scape primordium differentiation and stage of secondary and tertiary furcation scape primordium differentiation; Low temperature treatment of germinating seeds for 20 d in broccoli (T(20)) lowered 1.03 nodes and advanced 6 d for the critical stage of flower-bud differentiation , stage of primary furcation scape primordium differentiation and stage of secondary and tertiary furcation scape primordium differentiation. The node number at which flower-bud differentiation started under T(10) and T(20) was significantly lower than that of control while there was no significant difference between T(10) and T(20). In addition, the flower-bud differentiation was accompanied by increase in GA(3) contents, soluble protein contents, POD activities and invertase activities. GA(3) contents, soluble protein contents, POD activities and invertase activities started to increase significantly when plants entered the critical stage of flower-bud differentiation; POD activities, invertase activities and GA(3) contents emerge high apex value when plants entered stage of primary furcation scape primordium differentiation and stage of secondary and tertiary furcation scape primordium differentiation. Curve change trend of these physiological and biochemical indexes under T(10) and T(20) were accord with CK while advent of each high apex value was earlier about a week than CK during flower-bud differentiation. In a word, synthesization of GA(3) was induced firstly after germinating seeds were treated under low temperature, consequently POD activities and invertase activities were increased which took advantage of flower-bud differentiation. PMID:15627691

Jiang, Xin-Mei; Yu, Xi-Hong

2004-08-01

378

Overexpression of FAD2 promotes seed germination and hypocotyl elongation in Brassica napus  

Microsoft Academic Search

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

Maohua Wang; Mianxue Liu; Dekuan Li; Jun Wu; Xufeng Li; Yi Yang

2010-01-01

379

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

Microsoft Academic Search

Copper (Cu), though an essential micronutrient for plants, poses toxicity at higher concentrations possibly by inducing oxidative\\u000a stress. With the background that enzyme superoxide dismutase (SOD) ameliorates oxidative stress, the present work focused\\u000a on understanding physiological and proteomic response of Arabidopsis seeds constitutively over-expressing copper–zinc SOD of Potentilla atrosanguinea (PaSOD) during germination in response to varied concentrations of copper sulphate

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

380

Effects of salinity and desalination on seed germination of six annual weed species  

Microsoft Academic Search

The effects of various salinities and desalination on seed germination of six annual glycophytes (Artemisia sieversiana, A. scoparia, Chloris virgata, Eragrostis pilosa, Chenopodium acuminatum and Chenopodium glaucum) were studied in Horqin Sandy Land, Inner Mongolia, China. NaCl solutions of five concentrations (0 mM, as the control, and\\u000a 50, 100, 200 and 300 mM) were used for saline stress and desalination

Xue-hua Li; De-ming Jiang; Xiao-lan Li; Quan-lai Zhou; Jiang Xin

2011-01-01

381

Research article Induction of acid phosphatase activity during germination of maize (Zea mays) seeds  

Microsoft Academic Search

Acid phosphatase activity (orthophosphoric-monoester phosphohydrolase, EC 3.1.3.2) increased during the first 24 h of maize (Zea mays) seed germination. The enzyme displayed a pH optimum of 4.5-5.5. Catalytic activity in vitro displayed a linear time course (60 min) and reached its half maximum value at 0.47 mM p-nitrophenyl phosphate (pNPP). Phosphatase activity towards phosphoamino acids was greatest for phos- photyrosine.

R. Senna; V. Simonina; M. A. C. Silva-Neto; E. Fialho

382

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

PubMed

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

Yasur, Jyothsna; Rani, Pathipati Usha

2013-12-01

383

Phenolic compounds from Merremia umbellata subsp. orientalis and their allelopathic effects on Arabidopsis seed germination.  

PubMed

A bioassay-directed phytochemical study was carried out to investigate potential allelochemicals of the invasive plant Merremia umbellata subsp. orientalis (Hall. f.). Eight phenolic compounds, including a salicylic acid (SA)-derived new natural product, SA 2-O-?-D-(3',6'-dicaffeoyl)-glucopyranoside (1), and seven known ones 2-8 were isolated and identified from two bioactive sub-fractions of the acetone extract of this plant. The structure of new compound 1 was established by spectral and chemical methods. The potential allelopathic effects of these compounds at 0.5 and 1.0 mM concentrations on the germination of Arabidopsis seeds were tested. Results showed that 2 remarkably inhibited seed germination at concentrations as low as 0.5 mM. Compound 3 only moderately inhibited seed germination at 0.5 mM, but displayed strong inhibitory bioactivity at 1.0 mM concentration. Compounds 4 and 5 showed only slight inhibitory bioactivity at 1.0 mM, while the other compounds showed no obvious inhibitory effects. PMID:21076390

Yan, Jian; Bi, Hai-Hong; Liu, Yong-Zhu; Zhang, Mei; Zhou, Zhong-Yu; Tan, Jian-Wen

2010-11-01

384

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

PubMed

Effect of the size of rhizospheric bacterial populations on germination of seeds and development of simple terrestrial "wheat plants--rhizospheric microorganisms--artificial soil" and "wheat plants-artificial soil" systems has been studied. Experiments demonstrated that within specify ranges in the inoculate, the rhizospheric bacteria are capable of increasing the yield of germinated seeds and stimulate the growth of plantlets. Germination of seeds inoculated with bacteria was either stimulated, or inhibited or remained at control levels depending on the amount of bacteria. Plant biomass growth and total photoassimilation has been found to depend on the amount of bacteria on the plant roots: the higher the amount of bacteria on plant roots, the smaller is the biomass of plants but the total photoassimilation is, higher. Thus, depending on the amount of bacteria on the roots of plants the system either increases the biomass of plants or increases the total photoassimilation, i.e. "pumps" carbon through itself involving bacteria. Grant numbers: N99-04-96017, N15. PMID:11695444

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

2001-01-01

385

‘Safe sites’ for the seed germination of Rhus javanica : A characterization by responses to temperature and light  

Microsoft Academic Search

Germination responses ofRhus javanica L. seeds to temperature and light were investigated with special reference to their gap-detecting mechanisms in germination,\\u000a i.e., responses to elevated and\\/or fluctuating temperatures and sensitivity to leaf-canopy transmitted light. The seeds, which\\u000a have water-impermeable coats to prevent imbibition, were shown to become permeable and germinable after exposure to higher\\u000a temperatures of 48–74C for a brief

Izumi Washitani; Akio Takenaka

1986-01-01

386

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

PubMed

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

Ruiz-Ballesta, Isabel; Feria, Ana-Belén; Ni, Hong; She, Yi-Min; Plaxton, William Charles; Echevarría, Cristina

2014-02-01

387

Changes in germination and respiratory potential of embryos of dormant Grand Rapids lettuce seeds during long-term imbibed storage, and related changes in the endosperm  

Microsoft Academic Search

Grand Rapids lettuce (Lactuca sativa L.) seeds were stored in an imbibed state for up to two years. Embryos dissected from stored seeds showed a progressive loss with time in their ability to germinate on polyethylene glycol (PEG) solutions. Little germination of dissected embryos from one-month imbibed seeds occurred on-6 bar PEG but only after four months of storage did

Andrew D. Powell; Jacqueline Dulson; J. Derek Bewley

1984-01-01

388

Ammonia Volatilization from Urea-Application Influenced Germination and Early Seedling Growth of Dry Direct-Seeded Rice  

PubMed Central

Poor seed germination and early seedling growth associated with urea-induced soil ammonia volatilization are major constraints in the adoption of dry direct-seeded rice. To directly examine soil ammonia volatilization and its damage to seed germination and early seedling growth of dry direct-seeded rice when urea is applied at seeding, two Petri-dish incubation experiments and a field experiment were conducted. Ammonia volatilization due to urea application significantly reduced seed germination and early seedling growth of dry direct-seedling rice. NBPT significantly reduced ammonia volatilization following urea application. The application of ammonium sulfate, instead of urea at seeding, may mitigate poor crop establishment of dry direct-seeded rice. Root growth of dry direct-seeded rice was more seriously inhibited by soil ammonia volatilization than that of shoot. Results suggest that roots are more sensitive to soil ammonia toxicity than shoots in dry direct-seeded rice system when N is applied as urea at seeding.

Qi, Xiaoli; Wu, Wei; Shah, Farooq; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Liu, Hongyan; Nie, Lixiao

2012-01-01

389

Ammonia volatilization from urea-application influenced germination and early seedling growth of dry direct-seeded rice.  

PubMed

Poor seed germination and early seedling growth associated with urea-induced soil ammonia volatilization are major constraints in the adoption of dry direct-seeded rice. To directly examine soil ammonia volatilization and its damage to seed germination and early seedling growth of dry direct-seeded rice when urea is applied at seeding, two Petri-dish incubation experiments and a field experiment were conducted. Ammonia volatilization due to urea application significantly reduced seed germination and early seedling growth of dry direct-seedling rice. NBPT significantly reduced ammonia volatilization following urea application. The application of ammonium sulfate, instead of urea at seeding, may mitigate poor crop establishment of dry direct-seeded rice. Root growth of dry direct-seeded rice was more seriously inhibited by soil ammonia volatilization than that of shoot. Results suggest that roots are more sensitive to soil ammonia toxicity than shoots in dry direct-seeded rice system when N is applied as urea at seeding. PMID:22454611

Qi, Xiaoli; Wu, Wei; Shah, Farooq; Peng, Shaobing; Huang, Jianliang; Cui, Kehui; Liu, Hongyan; Nie, Lixiao

2012-01-01

390

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

NASA Astrophysics Data System (ADS)

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

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

391

Application of a Computer-Aided Image Analysis System to Evaluate Seed Germination under Different Environmental Conditions  

Microsoft Academic Search

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

A. DELL' AQUILA

392

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

Microsoft Academic Search

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

Il-Doo JIN; Song Joong YUN; Yuko MATSUISHI

393

Effects of biological soil crusts on seed germination of four endangered herbs in a xeric Florida shrubland during drought  

Microsoft Academic Search

Soil crusts of rosemary scrubs in south-central Florida were examined for effects on seed germination of four herbs that are killed by fire and must recruit from seed: Eryngium cuneifolium (Apiaceae), Hypericum cumulicola (Hypericaceae), Polygonella basiramia (Polygonaceae), and Paronychia chartacea ssp. chartacea (Caryophyllaceae). Biological soil crusts in these sites are dominated by algae, cyanobacteria, fungi, and bacteria. Because crusts can

Christine V. Hawkes

2004-01-01

394

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

Microsoft Academic Search

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

Chengwei Ren; Allison R. Kermode

2000-01-01

395

Exudation of low molecular weight organic acids by germinating seeds of two edaphic ecotypes of Silene nutans L  

Microsoft Academic Search

Two parapatric ecotypes of Silene nutans, exhibiting distinct allozyme patterns, morphology and autecology were investigated for differences in exudation of low molecular weight organic acids from germinating seeds, and for differences in seed phosphorus content. The calcicolous ecotype is restricted to calcareous soils, and the silicicolous one predominantly occurs on acid soils, and sometimes, although less frequently, on neutral to

Hans Henrik Bruun; Fabienne Van Rossum; Lena Ström

2001-01-01

396

Effects of altitude and seed size on germination and seedling survival of heathland plants in north Spain  

Microsoft Academic Search

The effects of altitude and seed size on germination and seedling survival were studied in Calluna vulgaris, Erica cinerea and Erica vagans. Experiments were carried out in the laboratory over a one year period. Seeds collected from heathlands of different altitudes were divided in two size classes. They were sowed on moist filter paper inside Petri dishes which were placed

M. L. Vera

1997-01-01

397

Sl-ERF2, a tomato ethylene response factor involved in ethylene response and seed germination.  

PubMed

Ethylene response factors (ERFs) are plant transcriptional regulators mediating ethylene-dependent gene expression via binding to the GCC motif found in the promoter region of ethylene-regulated genes. We report here on the structural and functional characterization of the tomato Sl-ERF2 gene that belongs to a distinct class of the large ERF gene family. Both spliced and unspliced versions of Sl-ERF2 transcripts were amplified from RNA samples and the search in the public tomato expressed sequence tag (EST) database confirmed the existence of the two transcript species in a number of cDNA libraries. The unspliced transcript contains two open reading frames yielding two hypothetical proteins, a small highly truncated version lacking the APETALA2 domain and a bigger protein lacking the N-terminal MCGGAAI(I)/(L) consensus peptide specific to ERF members from subfamily IV. Nevertheless, functional Sl-ERF2 protein may only derive from spliced transcripts since, depending on the tissue, the level of the spliced transcript is much higher than that of the unspliced transcript. Sl-ERF2 is expressed in all plant tissues tested, though its transcript accumulates preferentially in germinating seeds and ripening fruit. Overexpression of the Sl-ERF2 gene in transgenic tomato lines results in premature seed germination and enhanced hook formation of dark-grown seedlings, which is indicative of increased ethylene sensitivity. The expression of the mannanase2 gene is upregulated in Sl-ERF2-overexpressing seeds, suggesting that Sl-ERF2 stimulates seed germination through the induction of the mannanase2 gene. It is noteworthy that the exaggerated hook phenotype is abolished when ethylene perception is blocked, strongly suggesting that Sl-ERF2 requires other ethylene-dependent components to impact the hook formation process. PMID:16857696

Pirrello, Julien; Jaimes-Miranda, Fabiola; Sanchez-Ballesta, Maria Teresa; Tournier, Barthélémy; Khalil-Ahmad, Qaiser; Regad, Farid; Latché, Alain; Pech, Jean Claude; Bouzayen, Mondher

2006-09-01

398

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

PubMed Central

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.

Zhang, Wen-Hao

2012-01-01

399

Spatial Distribution of Epigenetic Modifications in Brachypodium distachyon Embryos during Seed Maturation and Germination  

PubMed Central

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.

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

2014-01-01

400

Karrikins discovered in smoke trigger Arabidopsis seed germination by a mechanism requiring gibberellic acid synthesis and light.  

PubMed

Discovery of the primary seed germination stimulant in smoke, 3-methyl-2H-furo[2,3-c]pyran-2-one (KAR1), has resulted in identification of a family of structurally related plant growth regulators, karrikins. KAR1 acts as a key germination trigger for many species from fire-prone, Mediterranean climates, but a molecular mechanism for this response remains unknown. We demonstrate that Arabidopsis (Arabidopsis thaliana), an ephemeral of the temperate northern hemisphere that has never, to our knowledge, been reported to be responsive to fire or smoke, rapidly and sensitively perceives karrikins. Thus, these signaling molecules may have greater significance among angiosperms than previously realized. Karrikins can trigger germination of primary dormant Arabidopsis seeds far more effectively than known phytohormones or the structurally related strigolactone GR-24. Natural variation and depth of seed dormancy affect the degree of KAR1 stimulation. Analysis of phytohormone mutant germination reveals suppression of KAR1 responses by abscisic acid and a requirement for gibberellin (GA) synthesis. The reduced germination of sleepy1 mutants is partially recovered by KAR1, which suggests that germination enhancement by karrikin is only partly DELLA dependent. While KAR1 has little effect on sensitivity to exogenous GA, it enhances expression of the GA biosynthetic genes GA3ox1 and GA3ox2 during seed imbibition. Neither abscisic acid nor GA levels in seed are appreciably affected by KAR1 treatment prior to radicle emergence, despite marked differences in germination outcome. KAR1 stimulation of Arabidopsis germination is light-dependent and reversible by far-red exposure, although limited induction of GA3ox1 still occurs in the dark. The observed requirements for light and GA biosynthesis provide the first insights into the karrikin mode of action. PMID:19074625

Nelson, David C; Riseborough, Julie-Anne; Flematti, Gavin R; Stevens, Jason; Ghisalberti, Emilio L; Dixon, Kingsley W; Smith, Steven M

2009-02-01

401

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

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

Chang, Gang; Xiao, Zhishu; Zhang, Zhibin

2009-09-01

402

Ecology of seed germination of eight non-pioneer tree species from a tropical seasonal rain forest in southwest China  

Microsoft Academic Search

We compared various aspects of the seed biology of eight non-pioneer tree species from a tropical seasonal rain forest in\\u000a Xishuangbanna, SW China, that differ in time of dispersal, size and fresh seed moisture content (MC). Seeds were tested for\\u000a germination under laboratory conditions after dehydration to different moisture levels and under 3.5, 10 and 30% solar irradiances\\u000a in neutral-shade

Yang Yu; Jerry M. Baskin; Carol C. Baskin; Yong Tang; Min Cao

2008-01-01

403

Gibberellin Requirement for Arabidopsis Seed Germination Is Determined Both by Testa Characteristics and Embryonic Abscisic Acid1  

Microsoft Academic Search

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

Isabelle Debeaujon; Maarten Koornneef

404

Effects of stratification and GA3 on seed germination of a sand stabilising grass Leymus arenarius used in reclamation  

Microsoft Academic Search

Seed of the sand-stabilising grass Leymus arenarius is used on a large-scale in dune reclamation in Iceland. Seed which is collected from wild populations is often dormant and methods of alleviating this dormancy were examined. Effects of gibberellic acid (GA3: 500 mgl -1 ) and prolonged (i.e. 2, 4 or 6 weeks) stratification (5°C) on seed germination of three refractory

S. GREIPSSON

405

Dehydration Injury in Germinating Soybean (Glycine max L. Merr.) Seeds 1  

PubMed Central

The sensitivity of soybean (Glycine max L. Merr. cv Maple Arrow) seeds to dehydration changed during germination. Seeds were tolerant of dehydration to 10% moisture if dried at 6 hours of imbibition, but were susceptible to dehydration injury if dried at 36 hours of imbibition. Dehydration injury appeared as loss of germination, slower growth rates of isolated axes, hypocotyl and root curling, and altered membrane permeability. Increased electrolyte leakage due to dehydration treatment was observed only from isolated axes but not from cotyledons, suggesting that cotyledons are more tolerant of dehydration. The transition from a dehydration-tolerant to a dehydration-susceptible state coincided with radicle elongation. However, the prevention of cell elongation by osmotic treatment in polyethylene glycol (?6 bars) or imbibition in 20 micrograms per milliliter cycloheximide did not prevent the loss of dehydration tolerance suggesting that neither cell elongation nor cytoplasmic protein synthesis was responsible for the change in sensitivity of soybean seeds to dehydration. Furthermore, the rate of dehydration or rate of rehydration did not alter the response to the dehydration stress.

Senaratna, Tissa; McKersie, Bryan D.

1983-01-01

406

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

PubMed Central

The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by limiting the detrimental activity of physical and biological agents during seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmentation and/or structure for dormancy, germination, and storability. The seeds of most mutants exhibited reduced dormancy. Moreover, unlike wild-type testas, mutant testas were permeable to tetrazolium salts. These altered dormancy and tetrazolium uptake properties were related to defects in the pigmentation of the endothelium and its neighboring crushed parenchymatic layers, as determined by vanillin staining and microscopic observations. Structural aberrations such as missing layers or a modified epidermal layer in specific mutants also affected dormancy levels and permeability to tetrazolium. Both structural and pigmentation mutants deteriorated faster than the wild types during natural aging at room temperature, with structural mutants being the most strongly affected.

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

2000-01-01

407

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

PubMed

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

Swartzberg, D; Hanael, R; Granot, D

2011-05-01

408

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

PubMed Central

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 GA4 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.

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

2013-01-01

409

Naringenin inhibits seed germination and seedling root growth through a salicylic acid-independent mechanism in Arabidopsis thaliana.  

PubMed

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

Hernández, Iker; Munné-Bosch, Sergi

2012-12-01

410

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

PubMed Central

Background Seed dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed dormancy breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed dormancy breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed dormancy breaking, would expand our knowledge about this process. Results A proteomic approach was used to analyse the mechanism of dormancy breaking in Norway maple seeds caused by cold stratification, and the participation of the abscisic (ABA) and gibberellic (GA) acids. Forty-four proteins showing significant changes were identified by mass spectrometry. Of these, eight spots were identified as water-responsive, 18 spots were ABA- and nine GA-responsive and nine spots were regulated by both hormones. The classification of proteins showed that most of the proteins associated with dormancy breaking in water were involved in protein destination. Most of the ABA- and GA-responsive proteins were involved in protein destination and energy metabolism. Conclusion In this study, ABA was found to mostly down-regulate proteins whereas GA up-regulated proteins abundance. Most of the changes were observed at the end of stratification in the germinated seeds. This is the most active period of dormancy breaking when seeds pass from the quiescent state to germination. Seed dormancy breaking involves proteins of various processes but the proteasome proteins, S-adenosylmethionine synthetase, glycine-rich RNA binding protein, ABI3-interacting protein 1, EF-2 and adenosylhomocysteinase are of particular importance. The effect of exogenously applied hormones was not a determining factor for total inhibition (ABA) or stimulation (GA) of Norway maple seed dormancy breaking and germination but proteomic data has proven these hormones play a role.

Pawlowski, Tomasz A

2009-01-01

411

Demethylesterification of Cell Wall Pectins in Arabidopsis Plays a Role in Seed Germination1[W][OA  

PubMed Central

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

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

2013-01-01

412

A rice lectin receptor-like kinase that is involved in innate immune responses also contributes to seed germination.  

PubMed

Seed germination and innate immunity both have significant effects on plant life spans because they control the plant's entry into the ecosystem and provide defenses against various external stresses, respectively. Much ecological evidence has shown that seeds with high vigor are generally more tolerant of various environmental stimuli in the field than those with low vigor. However, there is little genetic evidence linking germination and immunity in plants. Here, we show that the rice lectin receptor-like kinase OslecRK contributes to both seed germination and plant innate immunity. We demonstrate that knocking down the OslecRK gene depresses the expression of ?-amylase genes, reducing seed viability and thereby decreasing the rate of seed germination. Moreover, it also inhibits the expression of defense genes, and so reduces the resistance of rice plants to fungal and bacterial pathogens as well as herbivorous insects. Yeast two-hybrid and co-immunoprecipitation experiments revealed that OslecRK interacts with an actin-depolymerizing factor (ADF) in vivo via its kinase domain. Moreover, the rice adf mutant exhibited a reduced seed germination rate due to the suppression of ?-amylase gene expression. This mutant also exhibited depressed immune responses and reduced resistance to biotic stresses. Our results thus provide direct genetic evidence for a common physiological pathway connecting germination and immunity in plants. They also partially explain the common observation that high-vigor seeds often perform well in the field. The dual effects of OslecRK may be indicative of progressive adaptive evolution in rice. PMID:24033867

Cheng, Xiaoyan; Wu, Yan; Guo, Jianping; Du, Bo; Chen, Rongzhi; Zhu, Lili; He, Guangcun

2013-11-01

413

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

PubMed

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

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

2014-06-01

414

Losses of diesel oil by volatilisation and effects of diesel oil on seed germination and seedling growth.  

PubMed

For phytoremediation to be effective, seeds must germinate and subsequently grow, or seedlings must become established, in contaminated soil. In this study, the effect of diesel oil on the viability of seeds of white clover and ryegrass together with long term abiotic diesel oil loss were investigated. Losses of diesel by volatilisation were found to be as high as 58% over 360 days suggesting that volatilisation (abiotic loss) may be a significant method of contaminant removal that may have been previously underestimated or overlooked in short term studies. White clover and ryegrass seeds were able to germinate in the presence of volatile diesel components and following 24 weeks immersion in diesel oil, which suggested that properties of their seed coats prevented diesel oil causing damage to the seeds. PMID:11816772

Kroening, S J; Leung, D W; Greenfield, L G; Galilee, C

2001-09-01