The effect of sodium hypochlorite, gibberellic acid, and light on seed dormancy and germination of wild buckwheat (Polygonum convolvulus) and cow cockle (Saponaria vaccaria)

Seed germination of wild buckwheat (Polygonum convolvulus L.) and cow cockle (Saponaria vaccaria L.) increased with increasing time of immersion in 6% sodium hypochlorite (NaOCl). Maximum germination was obtained at 6 to 8 h for wild buckwheat and at 2 h for cow cockle. The effect of NaOCl treatment of wild buckwheat seeds mimics the effect of acid scarification. Wild buckwheat germination was not influenced by light and (or) gibberellic acid (GA3). To induce 50% germination (t½) of cow cockle NaOCl treatments of 0.5 and 1 h were required for seeds incubating in the dark and light, respectively. Once the seed coat was made more permeable by NaOCl, both the promoting effect of GA3 and the inhibitory effect of light were increased. When the optimum effect of NaOCl occurred, all the seeds germinated. However, prolonged NaOCl treatment resulted in either poor germination or seed disintegration.The hard coat seems to be the main factor in regulating wild buckwheat seed germination. Cow cockle, however, is regulated by at least two other factors, light and hormones, in addition to seed coat.

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Gibberellic Acid and Presowing Chilling Increase Seed Germination of Indiangrass [Sorghastrum nutans (L.) Nash.]

HortScience ◽

10.21273/hortsci.33.5.849 ◽

1998 ◽

Vol 33 (5) ◽

pp. 849-851 ◽

Cited By ~ 9

Author(s):

Jonathon I. Watkinson ◽

Wallace G. Pill

Keyword(s):

Seed Germination ◽

Gibberellic Acid ◽

Sodium Hypochlorite ◽

Seedling Emergence ◽

Dry Mass ◽

Sorghastrum Nutans ◽

Dormancy Breaking ◽

Germination Test ◽

Dry Storage

Following dry storage for 5 or 11 months (new and old seeds, respectively) at 5 °C, less than 10% of the seeds of Indiangrass germinated as determined by a standard germination test. We attempted to increase germination by subjecting seeds to dormancy-breaking treatments, including sodium hypochlorite soak (5.25% v/v NaOCl; 20 or 60 min), prechilling (5 °C for 2 weeks), gibberellic acid during germination (GA3, 1000 mg·L-1), and combinations thereof. Treatment with NaOCl increased the germination of non-prechilled seeds only when they were germinated in GA3; a 60-min soak in NaOCl increased germination to 53% and 65% in new and old seeds, respectively. Prechilling increased germination to 65% and 47% in new and old seeds, respectively. Germination of new, prechilled seeds was increased further to 86% by either a 20-min soak in NaOCl or germination in GA3. Germination of old, prechilled seeds was not promoted further by treatment with NaOCl, but was increased to 67% by germination in GA3. Since NaOCl treatment alone failed to promote germination, we examined the effects on seedling emergence and growth of providing GA3 at 1000 mg·L-1 during the 2-week prechilling period. While prechilling alone increased emergence to an average 34% for new and old seeds, prechilling with GA3 increased emergence to 75% and 50% for new and old seeds, respectively. These treatments did not influence seedling shoot dry mass. Seed exposure to GA3 during rather than after prechilling was more effective in promoting Indiangrass establishment.

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The effect of light and heat on 4CH and 200CH potencies of gibberellic acid as a promoter of germination in barley seed (Hordeum vulgare), measured by a germination index

10.51415/10321/2691 ◽

2002 ◽

Author(s):

◽

Hayley Pieterse

Keyword(s):

Hordeum Vulgare ◽

Seed Germination ◽

Gibberellic Acid ◽

Germination Index ◽

Barley Seed ◽

Effect Of Light

The purpose of this investigation was to evaluate the effects of light and heat on homoeopathic dilutions of gibberellic acid (cHGA3) as measured on Hordeum vulgare (barley) seed germination.

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Weed Seed Germination Responses to Chemical and Physical Treatments

Weed Science ◽

10.1017/s0043174500035220 ◽

1972 ◽

Vol 20 (2) ◽

pp. 150-153 ◽

Cited By ~ 20

Author(s):

R. E. Holm ◽

M. R. Miller

Keyword(s):

Abscisic Acid ◽

Seed Germination ◽

Gibberellic Acid ◽

Seed Coat ◽

Hot Water ◽

Weed Seed ◽

Weed Species ◽

Germination Response ◽

Weed Seeds ◽

Physical Treatments

The germination responses of seeds from 11 weed species to various chemical and physical treatments were studied. Germination of nine species was promoted by gibberellic acid and inhibited by abscisic acid, suggesting that germination of some weed seeds may be controlled by appropriate levels of these substances. Most of the weeds that germinated better after a hot-water soak treatment responded to sonication and infrared treatment, indicating that temperature was a factor in the germination response obtained with these methods, although physical disruption of the seed coat also was involved.

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(404) Effect of Seed Source, Light during Germination, and Cold-moist Stratification on Seed Germination in Three Species of Echinacea

HortScience ◽

10.21273/hortsci.40.4.1062e ◽

2005 ◽

Vol 40 (4) ◽

pp. 1062E-1062

Author(s):

Fredy R. Romero ◽

Kathleen Delate ◽

David J. Hannapel

Keyword(s):

Seed Germination ◽

Gibberellic Acid ◽

Seed Dormancy ◽

Organic Production ◽

Seed Source ◽

Seed Treatments ◽

Medicinal Species ◽

Effect Of Light

With the increase in popularity of echinacea as a botanical supplement, organic production of this herb continues to grow. Echinacea seeds typically show a high percentage of dormancy that can be broken by ethephon or gibberellic acid, but these methods are not accepted in organic production. We examined in three experiments the effects of varying seed source and germination conditions on echinacea growth. To determine the efficacy of nonchemical treatments, we evaluated the effect of light with and without cold-moist stratification on seed germination of the three most important medicinal species of echinacea, E. angustifolia, E. purpurea, and E. pallida. We used 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 enhanced in seeds from a commercial organic seed source, compared to a public germoplasm source. When seeds were not cold-moist stratified, light increased germination in E. angustifolia only, suggesting differential dormancy among the three species. We found that when seeds were cold-moist stratified under 16–24 h of light for 4 weeks, the percentage and rate of germination increased 10% over the control, suggesting this method as an alternative to chemical seed treatments.

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Germination in Photosensitive Seeds: Does Phytochrome Stimulate Metabolism of GA19 and GA20 to GA1?

Functional Plant Biology ◽

10.1071/pp96104 ◽

1997 ◽

Vol 24 (3) ◽

pp. 389 ◽

Cited By ~ 6

Author(s):

Julie A. Plummer ◽

Catherine J. McChesney ◽

David T. Bell

Keyword(s):

Seed Germination ◽

Gibberellic Acid ◽

White Light ◽

Red Light ◽

Biosynthesis Inhibitor ◽

Reduced Light ◽

Ga Biosynthesis ◽

Effect Of Light

The effect of light on gibberellic acid (GA) metabolism was investigated in Asteraceae seeds. White light (80 mmol m-2 s-1 PAR) increased seed germination in Craspedia sp., Erymophyllum ramosum and Rhodanthe chlorocephala subsp. splendida compared with darkness. In these taxa, red light (R, 640 nm, 8 mmol m-2 s-1) stimulated and far red light (FR, 720 nm, 4 mmol m-2 s-1) inhibited germination, indicating the involvement of phytochrome. Paclobutrazol, a GA biosynthesis inhibitor, reduced light-stimulated germination and this was overcome by exogenous GA3. GA3 and GA1 promoted germination in the dark, but GA19 and GA20, which are precursors to GA1, generally did not. GAs were applied to paclobutrazol-treated seeds which were incubated under either R or FR. Very few paclobutrazol-treated seeds germinated without GAs under FR, and exposure to R only marginally improved germination. Application of GA19 or GA20 to paclobutrazol-treated seeds increased germination in Rhodanthe chlorocephala subsp. splendida under R, with no germination under FR. This trend was observed in Craspedia sp., but not in Erymophyllum ramosum or Rhodanthe floribunda. CGA 163′935, a 3b-hydroxylation inhibitor, and R and FR were used to investigate phytochrome-stimulated conversion of GA19 and GA20 to GA1. It could not be shown that R was required for 3b-hydroxylation in light stimulated germination of these species.

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Faculty Opinions recommendation of Karrikins discovered in smoke trigger Arabidopsis seed germination by a mechanism requiring gibberellic acid synthesis and light.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1158953.619220 ◽

2009 ◽

Author(s):

Wolf B Frommer

Keyword(s):

Seed Germination ◽

Gibberellic Acid ◽

Acid Synthesis ◽

Arabidopsis Seed

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Asymbiotic germination of Vanilla planifolia in relation to the timing of seed collection and seed pretreatments

Botanical Studies ◽

10.1186/s40529-021-00311-y ◽

2021 ◽

Vol 62 (1) ◽

Author(s):

Chih-Hsin Yeh ◽

Kai-Yi Chen ◽

Yung-I. Lee

Keyword(s):

Seed Germination ◽

Seed Development ◽

Seed Coat ◽

Germination Percentage ◽

Vanilla Planifolia ◽

Outermost Layer ◽

Seed Collection ◽

Seed Pretreatment ◽

Immature Seeds ◽

Mature Seeds

Abstract Background Vanilla planifolia is an important tropical orchid for production of natural vanilla flavor. Traditionally, V. planifolia is propagated by stem cuttings, which produces identical genotype that are sensitive to virulent pathogens. However, propagation with seed germination of V. planifolia is intricate and unstable because the seed coat is extremely hard with strong hydrophobic nature. A better understanding of seed development, especially the formation of impermeable seed coat would provide insights into seed propagation and conservation of genetic resources of Vanilla. Results We found that soaking mature seeds in 4% sodium hypochlorite solution from 75 to 90 min significantly increased germination. For the culture of immature seeds, the seed collection at 45 days after pollination (DAP) had the highest germination percentage. We then investigated the anatomical features during seed development that associated with the effect of seed pretreatment on raising seed germination percentage. The 45-DAP immature seeds have developed globular embryos and the thickened non-lignified cell wall at the outermost layer of the outer seed coat. Seeds at 60 DAP and subsequent stages germinated poorly. As the seed approached maturity, the cell wall of the outermost layer of the outer seed coat became lignified and finally compressed into a thick envelope at maturity. On toluidine blue O staining, the wall of outer seed coat stained greenish blue, indicating the presence of phenolic compounds. As well, on Nile red staining, a cuticular substance was detected in the surface wall of the embryo proper and the innermost wall of the inner seed coat. Conclusion We report a reliable protocol for seed pretreatment of mature seeds and for immature seeds culture based on a defined time schedule of V. plantifolia seed development. The window for successful germination of culturing immature seed was short. The quick accumulation of lignin, phenolics and/or phytomelanins in the seed coat may seriously inhibit seed germination after 45 DAP. As seeds matured, the thickened and lignified seed coat formed an impermeable envelope surrounding the embryo, which may play an important role in inducing dormancy. Further studies covering different maturity of green capsules are required to understand the optimal seed maturity and germination of seeds.

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Light, Seed Coat and Gibberellic Acid in Relation to the Amylase Activity in Germinating Scots Pine Seeds (Pinus silvestris)

Physiologia Plantarum ◽

10.1111/j.1399-3054.1971.tb01098.x ◽

1971 ◽

Vol 25 (1) ◽

pp. 112-117 ◽

Cited By ~ 11

Author(s):

BENGT NYMAN

Keyword(s):

Gibberellic Acid ◽

Scots Pine ◽

Seed Coat ◽

Amylase Activity ◽

Pinus Silvestris

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The Effect of High Concentrations of Ethylene on Seed Germination of Douglas Fir (Pseudotsugamenziesii (Mirb.) Franco)

Canadian Journal of Forest Research ◽

10.1139/x75-058 ◽

1975 ◽

Vol 5 (3) ◽

pp. 419-423 ◽

Cited By ~ 4

Author(s):

Carey Borno ◽

Iain E. P. Taylor

Keyword(s):

Seed Germination ◽

Germination Rate ◽

Inhibitory Effect ◽

Germination Percentage ◽

Douglas Fir ◽

Control Treatment ◽

Continuous Exposure ◽

Short Term ◽

Short Term Exposure ◽

High Concentrations

Stratified, imbibed Douglas fir (Pseudotsugamenziesii (Mirb.) Franco) seeds were exposed to 100% ethylene for times between 0 and 366 h. Germination rate and germination percentage were increased by treatments up to 48 h. The 12-h treatment gave largest stimulation; 30% enhancement of final germination percentage over control. Treatment for 96 h caused increased germination rate for the first 5 days but reduced the germination percentage. Germinants were subject to continuous exposure to atmospheres containing 0.1 – 200 000 ppm ethylene in air, but it did not stimulate growth, and the gas was inhibitory above 100 ppm. Although some effects of high concentrations of ethylene may have been due to the lowering of oxygen supplies, this alone was insufficient to account for the full inhibitory effect. The mechanism of stimulation by short-term exposure to ethylene is discussed.

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