An evaluation of methods for breaking seed dormancy in kudzu (Pueraria lobata)

We evaluated several methods for breaking dormancy in seeds of the invasive weed Pueraria lobata (Willd.) Ohwi (kudzu). Seedlings from untreated seeds emerged from late March to early October 1999 in trays placed outdoors under natural weather conditions; mean cumulative percentage emergence was low (11%). In growth chamber experiments, germination percentages of untreated seeds ranged from 6 to 17%. All hand-scarified seeds germinated, whereas only 6% of intact seeds germinated. Other dormancy-breaking methods that produced higher germination percentages included exposure to ethyl alcohol for 6-12 h (24-86%), exposure to concentrated sulfuric acid for 1-2 h (65-81%), and exposure to moist heat for 5-300 s (30-80%). The influence of temperature on germination percentages of seeds following dry heat treatments depended on the duration of exposure. At 60 and 80°C, germination percentages increased with longer exposures to dry heat and were greatest after 720 min (27 and 60%, respectively). At 100°C, percent germination was greatest when seeds were exposed to dry heat for only 10 min (93%). Cold stratification at 5°C for 0-6 weeks did not increase seed germination percentages after exposure to a range of alternating thermoperiods. Similarly, dry storage at room temperature for 0, 200, or 400 days did not affect germination percentages in light or dark treatments.Key words: Pueraria lobata, physical dormancy, germination, phenology, acid scarification, warm stratification, cold stratification.

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SEED DORMANCY BREAKING TREATMENTS FORAFRICAN PURSLANE (Zaleya pentandra)

Planta Daninha ◽

10.1590/s0100-83582015000400001 ◽

2015 ◽

Vol 33 (4) ◽

pp. 623-629 ◽

Cited By ~ 2

Author(s):

S. MUNAWAR ◽

M. NAEEM ◽

H.H. ALI ◽

M. JAMIL ◽

M. IQBAL ◽

...

Keyword(s):

Seed Dormancy ◽

Arid Zone ◽

Hot Water ◽

Plant Management ◽

Dormancy Breaking ◽

Invasive Weed ◽

Hard Seed ◽

Dry Heat ◽

Breaking Dormancy ◽

Seed Scarification

ABSTRACT Understanding the mechanisms involved in releasing seed dormancy is crucial for effective plant management and renewal of species in the arid zone. Zaleya pentandra is an emerging invasive weed of the arid areas of Pakistan. We investigated the effects of different dormancy breaking treatments on the germination of Z. pentandra seeds. Seeds were treated with hot water (by placing them in boiling water for 5, 15, 30, 60, 90, 120, and 150 min), dry heat (by placing them in a preheated oven at 70 oC for 1, 2, and 4 hours; at 70 oC for 1, 2, 3, and 4 days, and at 200 oC for 5, 10, 15, 30, and 45 min) and stratification (by placing them at 2-5 ºC in a refrigerator for 5, 10, 30, and 60 min; for 3, 6, and 12 hours, and for 1, 2, 4, 8, 15, and 30 days). Seeds also were soaked in thiourea ([(NH2)2CS] (0, 2,500, 5,000, 7,500, and 10,000 mg L-1 for 24 h at 30 oC) and in KNO3 (0, 10,000, 20,000, 30,000, 40,000, 50,000, and 60,000 mg L-1 for 24 h at 30 oC). Additionally, seeds were scarified with HCl (for 3, 6, 9, 12, 15, 18, and 21 h), HNO3 (for 3, 6, 9, 12, 15, 18, and 21 h), and H2SO4 (for 20, 40, 60, 80, 100, and 120 min at 30 oC) and also mechanically scarified with sandpaper. Zaleya pentandra seeds showed typical signs of hard seed coat dormancy. Mechanical scarification and acid treatments promoted seed germination to a varying degree. Seed scarification with HNO3 for 12 to 18 h as well as with HCl for 12 h and 15 h was efficient in breaking dormancy of Z. pentandra seeds, providing germination up to 92.5%. Seed scarification with H2SO4 from 20 to 120 min showed little effect, whereas hot water, dry heat, stratification and various concentrations of thiourea and KNO3 were ineffective in breaking Z. pentandra seed dormancy.

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Dormancy-Breaking and Germination Requirements for Seeds of Sorbus alnifolia (Siebold & Zucc.) K.Koch (Rosaceae), a Mesic Forest Tree with High Ornamental Potential

Forests ◽

10.3390/f10040319 ◽

2019 ◽

Vol 10 (4) ◽

pp. 319

Author(s):

Yuhan Tang ◽

Keliang Zhang ◽

Yin Zhang ◽

Jun Tao

Keyword(s):

Seed Dormancy ◽

Seed Bank ◽

Soil Seed Bank ◽

Natural Habitat ◽

Eastern China ◽

Forest Tree ◽

Germination Percentage ◽

Cold Stratification ◽

Dormancy Breaking ◽

Breaking Dormancy

Sorbus alnifolia (Siebold & Zucc.) K.Koch (Rosaceae) is an economically important tree in the temperate forests of Eastern China. In recent decades, ever-increasing use and modification of forestlands have resulted in major degeneration of the natural habitat of S. alnifolia. Moreover, S. alnifolia seeds germinate in a complicated way, leading to a high cost of propagation. The current study aimed to determine the requirements for breaking seed dormancy and for germination as well as to characterize the type of seed dormancy present in this species. Moreover, the roles of temperature, cold/warm stratification, and gibberellic acid (GA3) in breaking dormancy were tested combined with a study of the soil seed bank. The results showed that intact seeds of S. alnifolia were dormant, requiring 150 days of cold stratification to achieve the maximum germination percentage at 5/15 °C. Exposure of the seeds to ranges of temperatures at 15/25 °C and 20/30 °C resulted in secondary dormancy. Scarifying seed coat and partial removal of the cotyledon promoted germination. Compared with long-term cold stratification, one month of warm stratification plus cold stratification was superior in breaking dormancy. Application of GA3 did not break the dormancy during two months of incubation. Seeds of S. alnifolia formed a transient seed bank. The viability of freshly matured S. alnifolia seeds was 87.65% ± 11.67%, but this declined to 38.25% after 6-months of storage at room temperature. Seeds of S. alnifolia have a deep physiological dormancy; cold stratification will be useful in propagating this species. The long chilling requirements of S. alnifolia seeds would avoid seedling death in winter.

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Seed anatomy and water uptake and their relation to seed dormancy of Ormosia paraensis Ducke

Journal of Seed Science ◽

10.1590/2317-1545v40n3177599 ◽

2018 ◽

Vol 40 (3) ◽

pp. 237-245

Author(s):

Breno Marques da Silva e Silva ◽

Camila de Oliveira e Silva ◽

Fabiola Vitti Môro ◽

Roberval Daiton Vieira

Keyword(s):

Sulfuric Acid ◽

Seed Dormancy ◽

Water Uptake ◽

Furniture Industry ◽

Palisade Layer ◽

Dormancy Breaking ◽

Physical Dormancy ◽

Seed Physiology ◽

Breaking Dormancy ◽

Hydrophobic Substances

Abstract: Ormosia paraensis Ducke has ornamental seeds widely used in the manufacture of bio-jewels and wood used in the furniture industry. For seedling production, the information on its seed physiology is scarce. Thus, the aim of this study was to assess methods for breaking dormancy and relate them to integument structure and water uptake by O. paraensis seeds. Seed dormancy-breaking was performed by mechanical scarification and soaking in sulfuric acid for 0, 15, 30, 60, 120, and 240 minutes. Dormancy‐broken seeds were compared with intact seeds. Seed integument is formed by a cuticle (hydrophobic substances), epidermis (macroesclereids of the palisade layer,), hypodermis (osteosclereids), and parenchyma cells. Intact seeds did not absorb water after 72 hours of soaking. The highest percentages and rates of seed germination were observed in treatments with mechanical scarification and soaking in sulfuric acid for 60 or 120 minutes. Seed soaking in sulfuric acid (H2SO4 p.a. 98.08%) for 60 or 120 minutes or mechanical scarification are adequate to overcome physical dormancy associated with O. paraensis seed integument impermeability to water or gases.

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Laboratory Methods for Breaking Dormancy in Garlic Mustard (Alliaria petiolata) Seeds

Invasive Plant Science and Management ◽

10.1614/ipsm-08-126.1 ◽

2009 ◽

Vol 2 (2) ◽

pp. 185-189 ◽

Cited By ~ 9

Author(s):

Lynn M. Sosnoskie ◽

John Cardina

Keyword(s):

Alliaria Petiolata ◽

Mustard Seed ◽

Cold Stratification ◽

Garlic Mustard ◽

Scanning Electron Micrographs ◽

Laboratory Methods ◽

Breaking Dormancy ◽

Percent Germination ◽

Seed Coats ◽

Mustard Seeds

AbstractGarlic mustard seeds are dormant at maturity, and 90 to 105 d of cold-moist stratification at 4 C have been used to induce germination. We studied methods for breaking dormancy and inducing germination without cold stratification, for use in laboratory and greenhouse experiments with garlic mustard. Seeds were collected from large infestations, stored at room temperature, and subjected to chemical and mechanical scarification treatments. For chemical scarification, seeds were immersed in 3% (v/v) H2O2 for 12, 24, or 48 h with constant stirring, or immersed in concentrated (95 to 97%) H2SO4 for 1 or 5 min with stirring. For mechanical scarification, seeds were placed in a sandpaper-lined tumbler for 1 or 3 s. Scarified seeds, along with non-scarified seeds, were placed in petri dishes on germination blotters saturated with gibberellic acid (GA3, 10−3 M) or deionized water, and incubated for 35 d at either 20/10 C or 15/6 C (12 hr/12 hr). None of the non-scarified seeds germinated, regardless of germination solution or temperature. Seeds germinated only following scarification, and only when imbibed in GA3 solutions. Seeds immersed in H2SO4 for 5 min or mechanically scarified for 3 s had the highest level of germination in GA3. Cumulative percent germination after 35 d was greater for seeds stored 30 mo (44 to 83%), than for seeds stored 6 (2 to 60%) or 18 mo (35 to 79%), regardless of scarification treatment. The germination results, along with scanning electron micrographs of seed coats, suggest that the intact garlic mustard seed coat is permeable to water but not GA3; therefore, both scarification and GA3 are needed to break dormancy and induce germination without cold stratification.

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Dormancy-breaking and germination requirements for seeds of Acacia papyrocarpa, Acacia oswaldii and Senna artemisioides ssp.×coriacea, three Australian arid-zone Fabaceae species

Australian Journal of Botany ◽

10.1071/bt14077 ◽

2014 ◽

Vol 62 (7) ◽

pp. 546 ◽

Cited By ~ 10

Author(s):

Leanne M. Pound ◽

Phillip J. Ainsley ◽

José M. Facelli

Keyword(s):

Arid Zone ◽

South Australia ◽

Dormancy Breaking ◽

Physical Dormancy ◽

Dry Heat ◽

Seed Mortality ◽

Wet Heat ◽

Pre Treatment ◽

Unpredictable Environment ◽

Germination Requirements

Physical dormancy is common in seeds of arid-land legumes. Improved understanding of germination requirements of hard-seeded species will further our understanding of arid lands and aid restoration projects. We studied the germination responses of Acacia papyrocarpa (Benth.), A. oswaldii (F.Muell) and Senna artemisioides (Gaudich. ex DC.) Randell ssp. × coriacea (Benth.) Randell from a chenopod shrubland in South Australia. Imbibition testing indicated that all three species had physical dormancy, but the proportion of dormant seeds was lower in A. oswaldii. This corresponded to a thinner testa in this species. Mechanisms tested to scarify seeds included mechanical scarification and different durations of wet or dry heat. Mechanically scarified seeds germinated readily, reaching maximum numbers in 10–15 days, independently of incubation temperatures, with the exception of S. artemisioides seeds, which germinated at a slower rate in cooler temperatures. Overall, wet heat was more effective than dry heat to alleviate physical dormancy, whereas dry heat in some cases resulted in seed mortality. On the basis of these results, it is recommended that seeds of A. papyrocarpa and S. artemisoides be pretreated with wet heat in future restoration programs. No pre-treatment is required for dormancy loss in A. oswaldii seeds. The different responses of seeds of these species suggest that their populations have varying strategies for persistence in this unpredictable environment.

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Dormancy-breaking and germination requirements of seeds of fourLoniceraspecies (Caprifoliaceae) with underdeveloped spatulate embryos

Seed Science Research ◽

10.1017/s0960258500000507 ◽

2000 ◽

Vol 10 (4) ◽

pp. 459-469 ◽

Cited By ~ 38

Author(s):

Siti N. Hidayati ◽

Jerry M. Baskin ◽

Carol C. Baskin

Keyword(s):

Soil Surface ◽

The Other ◽

Cold Stratification ◽

Dormancy Breaking ◽

Morphophysiological Dormancy ◽

Seed Maturity ◽

Breaking Dormancy ◽

Natural Temperature ◽

To Come ◽

Germination Requirements

AbstractDormancy-breaking requirements and types of dormancy were determined for seeds ofLonicera fragrantissimaLindl. & Paxt.,L. japonicaThunb.,L. maackii(Rupr.) Maxim. andL. morrowiiA. Gray. Seeds of all four species have underdeveloped spatulate embryos that are about 20–40%fully developed (elongated) when dispersed. Embryos in freshly matured, intact seeds grew better at 25/15°C than at 5°C. Gibberellic acid (GA3) (tested only in the light) was more effective in breaking dormancy inL. maackiiandL. morrowiithan inL. fragrantissimaandL. japonica. Warm- followed by cold stratification was required to break dormancy in seeds ofL. fragrantissima, whereas seeds ofL. japonicarequired cold stratification only. Thus, seeds ofL. fragrantissimahave deep simple morphophysiological dormancy (MPD) and those ofL. japonicanondeep simple MPD. About 50%of the seeds ofL. maackiirequired warm- or cold stratification only to come out of dormancy and 50% of those ofL. morrowiirequired warm stratification only, whereas the other 50% did not require stratification to germinate. Thus, about half of the seeds of the two species has nondeep simple MPD, and the other half has morphological dormancy (MD). In these laboratory tests, seeds ofL. japonica,L. maackii, andL. morrowiigenerally germinated to significantly higher percentages in light than in darkness; seeds ofL. fragrantissimawere not tested in darkness. Peaks of germination for seeds ofL. fragrantissima,L. japonica,L. maackiiandL. morrowiisown on a soil surface and covered withQuercusleaves under near-natural temperature conditions shortly after seed maturity and dispersal in late June 1997, late November 1997, early November 1996 and late June 1998, respectively, occurred in early March 1998, late February 1998, late March 1997 and early October 1998, respectively. The germination phenologies of seeds of the same species and seed lots buried in soil were similar to those of seeds under leaf litter. High percentages of seeds of all four species germinated both under litter (78–96%) and beneath the soil surface (78–97%). These germination patterns correspond closely with the requirements for embryo growth and dormancy break in the fourLoniceraspecies.

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Influence of environmental factors on germination and emergence ofPueraria lobata

Weed Science ◽

10.1017/s0043174500092304 ◽

1999 ◽

Vol 47 (5) ◽

pp. 585-588 ◽

Cited By ~ 15

Author(s):

David J. Susko ◽

J. Paul Mueller ◽

Janet F. Spears

Keyword(s):

Environmental Factors ◽

Seedling Emergence ◽

Soil Surface ◽

Pueraria Lobata ◽

Physical Dormancy ◽

Continuous Darkness ◽

Invasive Weed ◽

Edaphic Conditions ◽

Temperature Regimes ◽

Light Darkness

Laboratory and greenhouse studies were conducted to determine the effect of several environmental factors on seed germination and seedling emergence of the invasive weedPueraria lobata(kudzu). Germination occurred over a range of alternating temperatures from 15/6 to 35/25 C. Seed germinated equally well in alternating light/darkness and continuous darkness. At all temperature regimes, percentage germination was much greater for hand-scarified seed (95 to 100%) than for nonscarified seed (7 to 17%), indicating thatP. lobataseed possesses physical dormancy. Germination exceeded 51% in solutions with pH 5 to 9. Maximum germination (99%) was observed in distilled water at pH 5.4. Germination was greatly reduced in solutions with osmotic potentials below −0.4 MPa (28% at −0.6 MPa, and 13% at −0.9 MPa); no germination was observed at −1.3 MPa. Percentage emergence was greater than 45% at burial depths in soil of 0.5 to 10 cm, with maximal emergence (72 to 85%) at depths of 0.5 to 4 cm. Seed sown on the soil surface had low seedling emergence (< 13%). No seedlings emerged when seed was exposed to flooding for 7 d or more.Pueraria lobataseed is capable of germinating in a variety of climatic and edaphic conditions, but flooding may severely limit establishment of stands by seed.

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Dormancy-breaking Studies on Echinacea angustifolia

HortScience ◽

10.21273/hortsci.33.3.456f ◽

1998 ◽

Vol 33 (3) ◽

pp. 456f-457 ◽

Cited By ~ 1

Author(s):

Ali O. Sari ◽

Mario R. Morales ◽

James E. Simon

Keyword(s):

Native Americans ◽

Seed Germination ◽

Tap Water ◽

The United States ◽

Market Demand ◽

Dormancy Breaking ◽

Echinacea Angustifolia ◽

Native Populations ◽

Percent Germination ◽

Dry Heating

Echinacea is a medicinal plant native to North America. It was used extensively by native Americans in the treatment of their ailments. It is presently one of the most popular medicinal plants in the United States. Its popularity has created a large market demand for the roots and foliage of the plant. The gathering of echinacea from the wild is leading to the reduction of native populations and the destruction of its genetic diversity. Cultivation of medicinal echinaceas is hindered by a low seed germination. Dormancy breaking studies were done on freshly harvested seeds of Echinacea angustifolia. Seed lots were placed under light at a constant temperature of 25 °C and at alternate temperatures of 25/15 °C for 14/10 h, respectively. Germination was more rapid and uniform and percent germination higher at 25 °C than at 25/15 °C. Seed tap-water soaking, dry heating, and sharp heating alteration did not increase germination. The application of 1.0 mM ethephon (2-chloroethylphosphoric acid) increased seed germination to 94% at 25 °C and 86% at 25/15 °C. Untreated seeds gave 65% germination at 25 °C and 11% at 25/15 °C. The application of 2500 mg·L–1 and 3500 mg·L–1 of GA to dry seeds and 2500 mg·L–1 to seeds that have been soaked under tap water and then dried increased germination to 82%, 83%, and 83% at 25 °C and 64%, 78%, and 64% at 25/15 °C, respectively.

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Comparison of pre-treatments for inducing germination in highly dormant wheat genotypes

Canadian Journal of Plant Science ◽

10.4141/p03-008 ◽

2003 ◽

Vol 83 (4) ◽

pp. 729-735 ◽

Cited By ~ 3

Author(s):

M. A. Matus-Cádiz ◽

P. Hucl

Keyword(s):

Seedling Growth ◽

Biomass Yield ◽

Triticum Aestivum L ◽

Potassium Nitrate ◽

Dormancy Breaking ◽

Yield Data ◽

Breeding Populations ◽

Breaking Dormancy ◽

Seedling Length ◽

Pre Treatment

An effective dormancy-breaking method may be of interest to wheat (Triticum aestivum L.) breeders selecting for increased seed dormancy prior to advancing their populations in greenhouse grow-outs. The objective of this study was to identify an effective pre-treatment for breaking dormancy in wheat that did not result in seedling etiolation. In 2000, eight dormant (W98616, line 211, EMDR-4, EMDR-9, EMDR-14, RL4137, Columbus, and AC Domain) and one nondormant line (Roblin) were grown at two locations in Saskatchewan. Seeds were: (i) stored for zero to 21 wks at 24°C before incubating at 20°C for 7 d; (ii) incubated at 5, 10, 15, 20, and 25°C for 14 d; and (iii) treated with gibberellic acid (GA3) (0.0006 and 0.0014 M), potassium nitrate (KNO3) (0.01 and 0.02 M), chilling, heating, chilling with 0.01 M KNO3, and heating with 0.01 M KNO3 before incubating at 10°C for 14 d. Seedling growth was observed in a duplicated growth chamber experiment. Seedling length, first inter-node length, and biomass yield data were collected from plants grown from seeds treated with four effective pretreatments. Data were subjected to an ANOVA. Six to 18 weeks of storage at 24°C were required to break the dormancy (≥ 95% germination) in dormant genotypes. Incubation at 10°C was the most effective temperature for promoting germination in dormant seeds after 10d of testing. Four pre-treatments including 0.0006 M GA3, 0.0014 M GA3, chilling with 0.01 M KNO3, and heating with 0.01 M KNO3 led to ≥ 95% germination within 10 d of testing. Only GA3 treatments were associated with etiolated seedling growth. Heating with 0.01 M KNO3 or chilling with 0.01 M KNO3, applied before incubating at 10°C in darkness, may be of interest to breeders selecting for increased dormancy before advancing breeding populations in greenhouse grow-outs. Key words: Triticum, dormancy, nitrate, chilling, heating, etiolated seedling

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