Seed dormancy and dormancy-breaking conditions of 12 West African woody species with high reforestation potential in the forest-savanna ecotone of Côte d'Ivoire

Information on the regeneration ecology of native woody species of the forest-savanna ecotone of West Africa is scarce, which is a major impediment to their optimal utilization in large-scale restoration programmes. The scattered information that is available for some of these species reveals that freshly matured seed are dormant. However, environmental heterogeneity among different habitats may results in inter-population seed dormancy variation. Thus, our objective was to re-examine the dormancy of 12 species from the forest-savanna ecotone that have been targeted for reforestation. Specifically, we aimed to examine the water-permeability of the seeds and explore the effectiveness of acid scarification and heat treatment to alleviate dormancy. Four species belonging to families other than Fabaceae and Malvaceae had water-permeable seeds. Two of them had nondormant (ND) seeds, and seeds of the other two species had a mixture of ND and other kinds of dormancy (possibly physiological dormancy, PD). Most species of Fabaceae and Malvaceae had water-impermeable seeds. All seeds of three species had physical dormant (PY), and some seeds of the remaining species had PY, while others were ND or had PD. Acid-scarification was effective in breaking PY and in augmenting imbibition and germination of non-PY seeds, while heat treatment was moderately effective in breaking dormancy. In general, acid scarification for 1-30 minutes and heat treatment for one hour at 55-75°C were optimal to enhance seed germination, depending on species. The present study has wide practical implications for park conservationists and restoration ecologists interested in producing bulk quantities of high-quality planting stocks of native woody species for large-scale restoration programmes.

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Non-Deep Physiological Dormancy in Seed and Germination Requirements of Lysimachia coreana Nakai

Horticulturae ◽

10.3390/horticulturae7110490 ◽

2021 ◽

Vol 7 (11) ◽

pp. 490

Author(s):

Saeng Geul Baek ◽

Jin Hyun Im ◽

Myeong Ja Kwak ◽

Cho Hee Park ◽

Mi Hyun Lee ◽

...

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Germination Rate ◽

Seed Viability ◽

Cold Stratification ◽

Dormancy Breaking ◽

Viability Test ◽

Physiological Dormancy ◽

Different Temperatures ◽

Germination Requirements

This study aimed to determine the type of seed dormancy and to identify a suitable method of dormancy-breaking for an efficient seed viability test of Lysimachia coreana Nakai. To confirm the effect of gibberellic acid (GA3) on seed germination at different temperatures, germination tests were conducted at 5, 15, 20, 25, 20/10, and 25/15 °C (12/12 h, light/dark), using 1% agar with 100, 250, and 500 mg·L−1 GA3. Seeds were also stratified at 5 and 25/15 °C for 6 and 9 weeks, respectively, and then germinated at the same temperature. Seeds treated with GA3 demonstrated an increased germination rate (GR) at all temperatures except 5 °C. The highest GR was 82.0% at 25/15 °C and 250 mg·L−1 GA3 (4.8 times higher than the control (14.0%)). Additionally, GR increased after cold stratification, whereas seeds did not germinate after warm stratification at all temperatures. After cold stratification, the highest GR was 56.0% at 25/15 °C, which was lower than the GR observed after GA3 treatment. We hypothesized that L. coreana seeds have a non-deep physiological dormancy and concluded that 250 mg·L−1 GA3 treatment is more effective than cold stratification (9 weeks) for L. coreana seed-dormancy-breaking.

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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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Investigation of Potential Seed Dormancy Mechanisms in American Burnweed (Erechtites hieraciifolius) Seeds from Wild Blueberry (Vaccinium angustifolium) fields

Weed Science ◽

10.1017/wsc.2016.21 ◽

2017 ◽

Vol 65 (2) ◽

pp. 256-265

Author(s):

Scott N. White ◽

Linshan Zhang ◽

Kris Pruski

Keyword(s):

Seed Dormancy ◽

Seed Treatment ◽

Potassium Nitrate ◽

Weed Species ◽

Cold Temperatures ◽

Breaking Dormancy ◽

Physiological Dormancy ◽

Series Of Experiments ◽

Favorable Conditions ◽

Wild Blueberry

American burnweed is an increasingly common annual weed in wild blueberry fields in Atlantic Canada and Maine. Knowledge of seed dormancy characteristics and potential for this species to form persistent seedbanks in wild blueberry soils, however, is lacking. A series of experiments were therefore conducted to investigate potential mechanisms regulating American burnweed seed dormancy in wild blueberry fields. Seeds were dormant at maturity and did not germinate in dark or light under warm conditions. Cold moist stratification (CMS) at 4 C for 90 d followed by exposure to warm conditions (22/15 C day/night) and light caused >90% germination, and germination was generally maximized following 80 d CMS. Exogenous potassium nitrate applied as a 5% solution did not stimulate germination, but nearly all seeds (>95%) germinated following treatment with 200, 400, 600, or 800 ppm (w/v) gibberellic acid (GA3) solution. Physical removal of the seed coat or seed exposure to short durations of dry heat did not increase germination. Seed exposure to 1 s of direct flame increased germination, but germination was low relative to germination following CMS and treatment with GA3. Based on these results, we conclude that American burnweed seeds in wild blueberry fields exhibit non–deep physiological dormancy that is most readily broken by CMS and light or seed treatment with GA3. Seeds will likely be exposed to favorable conditions for breaking dormancy (cold temperatures and light) in wild blueberry fields due to lack of tillage and seed burial, indicating high potential for this weed species to proliferate in wild blueberry fields if not properly managed.

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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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Effects of different treatments on seed dormancy breaking and germination in Acer cappadocicum Gleditsch var. cappadocicum

Šumarski list ◽

10.31298/sl.144.3-4.5 ◽

2020 ◽

Vol 144 (3-4) ◽

pp. 159-166

Author(s):

Hanife Erdogan Genç ◽

Ali Ömer Üçler

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Germination Percentage ◽

Growth Chamber ◽

Dormancy Breaking ◽

Seed Collection ◽

Physiological Dormancy ◽

Germination Value ◽

Positive Effect ◽

Collection Time

This study was carried out to determine effects of different pretreatment on seed germination and to overcome dormancy in Acer cappadocicum seeds. The seeds were collected in 2008 three times with aproximately 15-days intervals. In order to overcome dormancy, several germination treatments were applied. The treatments were (1) different seed collection time, (2)soaking in water, (3) cold-moist stratification and (4) GA3 (gibberellic acid) application. The treated seeds were germinated in growing chamber at 5 0C and in greenhouse conditions. This research showed that seeds of Acer cappadocicum exhibit physiological dormancy and require stratification period to overcome seed dormancy. The highest germination percentage in the growing chamber subjected to GA3 process after eight weeks of stratification treatment was 62 % for Acer cappadocicum seeds. The highest germination percentage in greenhouse was obtained with cold stratification after eight weeks (95 %). It was found out that GA3 treatment had a significant effect on germination in growth chamber + 5 0C but GA3 treatment didn’t have a significant effect on germination in greenhouse conditions. GA3 treatment and soaking of unstratified seeds in water for 48 hr didn’t have any positive effect on germination value in greenhouse conditions. Although growth chamber and green house results both indicated that seed collection time did not seem to play a role as statistically on seed germination, Duncan’s test showed that the third seed collection time was in a different group.

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Effects of immersing dry seeds in alkaline solutions on seed dormancy and water uptake in wild oat (Avena fatua)

Canadian Journal of Plant Science ◽

10.4141/cjps94-005 ◽

1994 ◽

Vol 74 (1) ◽

pp. 19-24 ◽

Cited By ~ 7

Author(s):

J. Q. Hou ◽

G. M. Simpson

Keyword(s):

Seed Dormancy ◽

Water Uptake ◽

Seed Coat ◽

Treatment Time ◽

Alkaline Treatment ◽

Avena Fatua ◽

Alkaline Solutions ◽

Wild Oat ◽

Dormancy Breaking ◽

Breaking Dormancy

Effects of immersing dry seeds in KOH and NaOH solutions on seed dormancy and water uptake were studied in three dormant lines of wild oat (Avena fatua L.). KOH was more effective than NaOH in breaking dormancy. Maximum dormancy-breaking effect of 5.3 N KOH could be achieved with a 10- or 15-min treatment. Increase in treatment time did not necessarily increase germination; rather, it caused damage to the seeds. For 10-min treatment, 5.3 and 7.6 N KOH solutions were more effective than 3 and 9.8 N. Genetic lines responded differently to the KOH treatment. Initial rate and amount of water uptake by KOH-treated seed were significantly higher than by the untreated. It is believed that breaking dormancy by the alkaline treatment is related to removing the barrier to water uptake formed by the seed coat. Key words: Alkalis, Avena fatua, dormancy, seed coat, seedling growth

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Dormancy-breaking and germination requirements for seeds of Diervilla lonicera (Caprifoliaceae), a species with underdeveloped linear embryos

Canadian Journal of Botany ◽

10.1139/b00-094 ◽

2000 ◽

Vol 78 (9) ◽

pp. 1199-1205 ◽

Cited By ~ 5

Author(s):

Siti N Hidayati ◽

Jerry M Baskin ◽

Carol C Baskin

Keyword(s):

Seed Dormancy ◽

Constant Darkness ◽

Cold Stratification ◽

Dormancy Breaking ◽

Morphophysiological Dormancy ◽

Germination Phenology ◽

Physiological Dormancy ◽

Temperature Controlled ◽

Germination Requirements ◽

Morphological Dormancy

Dormancy-breaking requirements and type of dormancy were determined for seeds of Diervilla lonicera Mill. Seeds have an underdeveloped linear embryo that is about 35% of the length of the seed at maturity. Embryos (in intact seeds) grew at 25:15°C but not at 5°C. Up to 85% of the freshly matured seeds had morphological dormancy (MD), and thus, they germinated within about 30 days on a moist substrate in light at 30:15°C; a maximum of 3% of the seeds germinated in constant darkness. The other portion of fresh seeds had nondeep simple morphophysiological dormancy (MPD) and required a period of warm stratification or treatment with GA3 to break dormancy. These seeds also required light to germinate. In contrast, cold stratification induced dormancy, and dry storage for up to 1 year did not effectively break dormancy. Seeds with MD germinated to significantly higher percentages on soil than on filter paper or on sand. Seeds sown on soil in a non-temperature-controlled greenhouse in mid-November germinated mostly in late May, whereas those sown in mid-April germinated in early May. Apparently, embryos of November-sown seeds were induced into physiological dormancy during winter. Thus, seeds had MPD in spring and needed several weeks of warm temperatures for dormancy break, embryo growth, and germination. This is the first report on seed dormancy in the genus Diervilla.Key words: embryo growth, germination phenology, Diervilla lonicera, morphological seed dormancy, morphophysiological seed dormancy, underdeveloped linear embryo.

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Physiological dormancy in seeds of tropical montane woody species in Hawai`i

Plant Species Biology ◽

10.1111/1442-1984.12295 ◽

2020 ◽

Author(s):

Carol C. Baskin ◽

Jerry M. Baskin ◽

Alvin Yoshinaga ◽

Dustin Wolkis

Keyword(s):

Woody Species ◽

Physiological Dormancy

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Practical Methods for Breaking Seed Dormancy in a Wild Ornamental Tulip Species Tulipa thianschanica Regel

Agronomy ◽

10.3390/agronomy10111765 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1765

Author(s):

Wei Zhang ◽

Lian-Wei Qu ◽

Jun Zhao ◽

Li Xue ◽

Han-Ping Dai ◽

...

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Combined Treatment ◽

Individual Treatment ◽

Cold Stratification ◽

Slight Effect ◽

Sowing Depth ◽

Physiological Dormancy ◽

Commercial Breeding ◽

Breaking Seed Dormancy

The innate physiological dormancy of Tulipa thianschanica seeds ensures its survival and regeneration in the natural environment. However, the low percentage of germination restricts the establishment of its population and commercial breeding. To develop effective ways to break dormancy and improve germination, some important factors of seed germination of T. thianschanica were tested, including temperature, gibberellin (GA3) and/or kinetin (KT), cold stratification and sowing depth. The percentage of germination was as high as 80.7% at a constant temperature of 4 °C, followed by 55.6% at a fluctuating temperature of 4/16 °C, and almost no seeds germinated at 16 °C, 20 °C and 16/20 °C. Treatment with exogenous GA3 significantly improved the germination of seeds, but KT had a slight effect on the germination of T. thianschanica seeds. The combined treatment of GA3 and KT was more effective at enhancing seed germination than any individual treatment, and the optimal hormone concentration for the germination of T. thianschanica seeds was 100 mg/L GA3 + 10 mg/L KT. In addition, it took at least 20 days of cold stratification to break the seed dormancy of T. thianschanica. The emergence of T. thianschanica seedlings was the highest with 82.4% at a sowing depth of 1.5 cm, and it decreased significantly at a depth of >3.0 cm. This study provides information on methods to break dormancy and promote the germination of T. thianschanica seeds.

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