NaOH Scarification and Stratification Improve Germination of Iris lactea var. chinensis Seed

Iris lactea seed is characterized mainly by physiological dormancy. Two experiments were conducted to investigate the effect of NaOH treatment and stratification on Iris seed germination. In Experiment 1, seeds were treated with 14.38 m NaOH for 0 to 28 hours. In Experiment 2, NaOH treated and nontreated seeds were stratified under 7 °C and moistened condition for 0 to 40 days. As results, NaOH treatment for 20 hours effectively removed seedcoat and improved germination percentage from 0% to 56% compared to control (0 hours). However, germination percentage started to decrease after 20 hours. Stratification for 40 days further improved germination percentage of NaOH treated seeds to >80%, but did not affected seeds without NaOH treatment. Results demonstrate that combination of NaOH treatment and stratification is an effective practice to break Iris seed dormancy and improve germination percentage.

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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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Dormancy breakage in Cercis chinensis seeds

Canadian Journal of Plant Science ◽

10.1139/cjps-2019-0229 ◽

2020 ◽

Vol 100 (6) ◽

pp. 666-673

Author(s):

Yunpeng Gao ◽

Mingwei Zhu ◽

Qiuyue Ma ◽

Shuxian Li

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Seed Coat ◽

Germination Percentage ◽

Physical Dormancy ◽

Optimal Method ◽

Hard Seed ◽

Positive Effects ◽

Physiological Dormancy ◽

Hard Seed Coat

The seeds of Cercis chinensis Bunge are important for reproduction and propagation, but strong dormancy controls their germination. To elucidate the causes of seed dormancy in C. chinensis, we investigated the permeability of the hard seed coat and the contribution of the endosperm to physical dormancy, and we examined the effect of extracts from the seed coat and endosperm. In addition, the effectiveness of scarification methods to break seed dormancy was compared. Cercis chinensis seeds exhibited physical and physiological dormancy. The hard seed coat played an important role in limiting water uptake, and the endosperm acted as a physical barrier that restricted embryo development in imbibed seeds. Germination percentage of Chinese cabbage [Brassica rapa subsp. chinensis (L.) Hanelt] seeds was reduced from 98% (control) to 28.3% and 56.7% with a seed-coat extract and an endosperm extract, respectively. This demonstrated that both the seed coat and endosperm contained endogenous inhibitors, but the seed-coat extract resulted in stronger inhibition. Mechanical scarification, thermal scarification, and chemical scarification had positive effects on C. chinensis seed germination. Soaking non-scarified seeds in gibberellic acid (GA3) solution did not promote germination; however, treatment with exogenous GA3 following scarification significantly improved germination. The optimal method for promoting C. chinensis seed germination was soaking scarified seeds in 500 mg·L−1 GA3 for 24 h followed by cold stratification at 5 °C for 2 mo.

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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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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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Factors Affecting Seed Dormancy and Germination of Greater Bur-Parsley (Turgenia latifolia)

Planta Daninha ◽

10.1590/s0100-83582018360100125 ◽

2018 ◽

Vol 36 ◽

Author(s):

M. REZVANI ◽

S.A. SADATIAN ◽

H. NIKKHAHKOUCHAKSARAEI

Keyword(s):

Seed Germination ◽

Environmental Factors ◽

Seed Dormancy ◽

Seedling Emergence ◽

Potassium Nitrate ◽

Germination Percentage ◽

Dormancy Breaking ◽

Planting Depth ◽

Factors Affecting ◽

Drought And Salt Stresses

ABSTRACT: Our knowledge about seed dormancy breaking and environmental factors affecting seed germination of greater bur-parsley (Turgenia latifolia) is restricted. This study has addressed some seed dormancy breaking techniques, including different concentrations of gibberellic acid (GA3) and potassium nitrate (KNO3), leaching duration, physical scarification as well as some environmental factors effective on seed germination such as salt and drought stresses, pH and seed planting depth. Seed germination was promoted with lower concentrations of KNO3 (0.01 to 0.02 g L-1), while higher concentrations reduced germination percentage. Seed dormancy was declined by low concentrations of GA3 up to 100 ppm. Seeds of greater bur-parsley germinated in a range of pH from 3 to 7. With enhancement of drought and salt stresses, seed germination decreased. Also, there was no seed germination in a high level of stresses. Seedling emergence reduced as planting depth increased. Use of GA3, KNO3, leaching and physical scarification had a positive effect on seed dormancy breaking of greater bur-parsley. The information from the study increases our knowledge about seed dormancy breaking techniques, response of germination to drought and salt stresses and also determination of distribution regions of greater bur-parsley in the future.

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Variation in Piceaglauca seed germination associated with the year of cone collection

Canadian Journal of Forest Research ◽

10.1139/x93-167 ◽

1993 ◽

Vol 23 (7) ◽

pp. 1306-1313 ◽

Cited By ~ 7

Author(s):

G.E. Caron ◽

B.S.P. Wang ◽

H.O. Schooley

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Storage Period ◽

White Spruce ◽

Germination Percentage ◽

Degree Days ◽

Seed Maturity ◽

Individual Trees ◽

Collection Time

The effects of cone storage period and pregermination treatment on seed maturity and dormancy were compared for cones of white spruce (Piceaglauca (Moench) Voss) collected from individual trees in 1984 and 1988. Seeds were extracted from cones and germinated after 2 or 6 weeks of cone storage in 1984 and after 2, 4, 6, 10, or 14 weeks in 1988. Based on cumulative degree-days, seeds were more mature at collection time in 1988 than in 1984. Seeds from 1984 cones stored for 6 weeks matured during storage, and both germination percentage (GP) and rate of germination (GR) were significantly improved. In contrast, storage up to 14 weeks in 1988 did not increase GP and GR, as seed had attained maturity prior to cone collection. Seed dormancy was present in both 1984 and 1988. Significant improvements in GP and GR were achieved in 1984 with a pregermination treatment even before seed maturity was attained. Prechilling of seed after 6 weeks of cone storage increased GP from 60 to 95% in 1984 and 64 to 89% in 1988.

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Enhanced germination performance of dormant seeds of Eragrostis tef in the presence of light

Tropical Grasslands - Forrajes Tropicales ◽

10.17138/tgft(7)244-251 ◽

2019 ◽

Vol 7 (3) ◽

pp. 244-251

Author(s):

Iskender Tiryaki ◽

Sakir Anil Kaplan

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Plant Hormones ◽

Indole Acetic Acid ◽

Germination Percentage ◽

Eragrostis Tef ◽

Crop Establishment ◽

Giberellic Acid ◽

Related Plant ◽

Time Required

Lack of germination or low germination due to seed dormancy prevents successful crop establishment in several important plants. To determine the presence of innate seed dormancy and effects of stress-related plant hormones on germination performance of Teff (Eragrostis tef) seeds, we primed seeds in 1% KNO3 for 24 hours in dark conditions at 21 ± 0.5 ºC along with varying concentrations of chemicals known to influence seed germination, including: acetyl salicylic acid (ASA); methyl jasmonate (JA-Me); giberellic acid (GA3); and indole acetic acid (IAA). Primed seeds were incubated either in constant light (210 µM/m2/s) or in darkness at 21 ± 0.5 ºC. The results indicated that primingsignificantly improved final germination percentage (FGP) in both light (92.5%) and dark (89.4%) conditions compared with untreated seeds. The inclusion of plant hormones in the priming media generally had limited effects, except for 10 mM ASA (94.5%) and 100 mM GA3 (92.5%). ASA generally provided faster seed germination than seeds primed in 1% KNO3 only, while the other plant hormones had no effect on the time required for 50% of FGP in the dark. Priming had no significant effect on time span of germination in either light or dark incubation conditions. The results demonstrate that E. tef has light-inducible seed germination and about half of freshly harvested seeds can be dormant, which can be eliminated to some extent by priming seeds in 1% KNO3.

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The Effect of Sodium Hypochlorite (NaOCl) and Heat Treatments on Seed Germination of Rice: An Approach to Restore Seed Viability

Journal of Experimental Agriculture International ◽

10.9734/jeai/2021/v43i530689 ◽

2021 ◽

pp. 49-53

Author(s):

Monoj Sutradhar ◽

Subhasis Samanta ◽

Brijesh Kumar Singh ◽

Md. Nasim Ali ◽

Nirmal Mandal

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Sodium Hypochlorite ◽

Seed Viability ◽

Germination Percentage ◽

Heat Treated ◽

Mother Plants ◽

Breaking Seed Dormancy ◽

One Year

Dormancy in rice serves as a mechanism of survival by protecting the seed from germinating in the mother plants; however, it becomes a problem in germination during sowing in soil or under in vitro conditions. This study was conducted to determine the effect of heat treatment and sodium hypochlorite (NaOCl) treatment of seeds on dormancy alleviation. The seeds included both freshly harvested seeds and one-year-old stored seeds, which were tested for germination after different types of seed treatments. Both the treatments increased the germination percentage in seeds, however, it was lesser in the case of old seeds. The best results were obtained from 2% NaOCl treatment for 24 hrs in new seeds, i.e. 92.84±0.103 % germination percentage (GP). However, the higher GP in old seeds were obtained from 48 hrs of heat-treated seeds i.e. 82.9±0.509 % GP. The results of the experiment revealed that rice seeds start to lose viability within a year due to seed dormancy, but this can be reversed with proper measures. These methods of breaking seed dormancy can be considered effective to break seed dormancy and improve seed germination in rice.

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Effects of Temperature, Scarification, Stratification, Phytohormones, and After-Ripening on the Dormancy and Germination of Eucommia ulmoides Oliv. Seeds

Forests ◽

10.3390/f12111593 ◽

2021 ◽

Vol 12 (11) ◽

pp. 1593

Author(s):

Shiming Deng ◽

Zhijun Deng ◽

Xiaofeng Wang ◽

Hai Lu ◽

Hua Xue

Keyword(s):

Seed Germination ◽

Water Absorption ◽

Seed Dormancy ◽

Seed Coat ◽

Underlying Mechanism ◽

Germination Percentage ◽

Growth Potential ◽

Eucommia Ulmoides ◽

Germplasm Resources ◽

Type 3

Eucommia ulmoides Oliv., the only member of the family Eucommiaceae, is endemic to China and has great development and utilization prospects. The seeds of E. ulmoides show dormancy but the underlying mechanism remains unknown. The aim of this study was to determine the cause of the seed dormancy and provide fundamental knowledge for the breeding, genetic improvement, and conservation of the germplasm resources of this species. According to the seed dormancy classification system developed by Jerry M. Baskin and Carol C. Baskin, we compared the germination percentage between intact seeds and isolated embryos, constructed water absorption curves, and evaluated the germination of seeds treated with scarification, cold/warm-moist stratification, after-ripening during dry storage, and gibberellic acid (GA3). The results showed that the intact seeds germinated only at 10 °C with a low germination percentage of 13.3% whereas the isolated embryos had a high normal germination percentage among a wider range of temperatures. According to the results from the scarified seeds, half seeds, and intact seeds, the seed coat significantly restricted the embryo water absorption. The scarification, after-ripening, cold/warm-moist stratification, and GA3 treatments promoted seed germination. Among them, cold-moist stratification was the most effective method and the temperature range of seed germination increased in both directions from 10 °C with prolonged stratification. The germination percentage increased significantly at constant temperatures with the highest germination percentage of 93.7 ± 0.3% at 10 °C and a light/dark cycle after 90 days of cold-moist stratification. Therefore, the freshly harvested E. ulmoides seeds exhibited a combinational dormancy comprising physical and Type 3 non-deep physiological dormancy, causing limited embryo water absorption by the seed coat and a low embryo growth potential. Given the unique phylogenetic characteristics and utility of E. ulmoides, our findings should promote studies of seed dormancy evolution and the development and application of E. ulmoides germplasm resources.

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Pre-Germination Treatments, Temperature, and Light Conditions Improved Seed Germination of Passiflora incarnata L.

Agriculture ◽

10.3390/agriculture11100937 ◽

2021 ◽

Vol 11 (10) ◽

pp. 937

Author(s):

Luciana G. Angelini ◽

Clarissa Clemente ◽

Silvia Tavarini

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Large Scale ◽

Seed Quality ◽

Central Italy ◽

Germination Percentage ◽

Climatic Conditions ◽

Added Value ◽

Medicinal And Aromatic Plants ◽

Passiflora Incarnata

Perennial medicinal and aromatic plants (MAPs) may represent interesting, environmentally friendly crops for the Mediterranean environments. Among MAPs, Passiflora incarnata L. (maypop) represents a very promising crop for its wide adaptability to diverse climatic conditions, low input requirements, and high added-value due to its unique medicinal properties. The main problem in P. incarnata large-scale cultivation is the poor seed quality with erratic and low seed germination, due to its apparent pronounced seed dormancy. Therefore, the aim of this work was to investigate different chemical and physical treatments for overpassing seed dormancy and enhancing seed germination rates of P. incarnata. The effects of (i) different pre-germination treatments (pre-chilling, gibberellic acid—GA3, leaching, scarification, non-treated control), (ii) light or darkness exposure, and (iii) temperature conditions (25, 30, and 35 °C constant and 20–30 °C alternating temperatures) have been examined in seed germination percentage and mean germination time of three P. incarnata accessions (F2016, FF2016, and A2016) grown in field conditions in Central Italy. Data showed that the pre-germination treatments generally stimulated faster germination compared to the control, with the best results obtained in the dark and with high temperatures. These findings are useful for the choice of the most suitable seed pre-germination treatment that can facilitate stable, high and agronomically acceptable germination rates in P. incarnata.

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