Temperature Requirements for Seed Germination of Three Penstemon Species'

To determine optimum germination temperatures and effective dormancy-breaking procedures, field-grown (1983-85) seeds of `Bandera' Rocky Mountain penstemon (Penstemon strictus Benth), `Cedar' Palmer penstemon (Penstemon palmeri Gray), and firecracker penstemon (Penstemon eatonii Gray) were subjected to various cold stratification and incubation temperature treatments. Increased germination following an 8-week stratification occurred in seed lots containing dormant seeds, but a 2-week stratification generally failed to break dormancy. Older (1983) seeds of `Bandera' and `Cedar' penstemon germinated to full viability without stratification. All species showed a marked decrease in germination percentage above 20C; 15C consistently produced maximum germination after 4 weeks. At 15C, mean times to 90% of total germination were 11, 22, and 29 days for `Bandera', `Cedar', and firecracker penstemon, respectively. Transfer of seeds failing to germinate at warm temperatures (25 and 30C) to 15C and applying 720 μm gibberellic acid (GA3) solution was effective in breaking primary dormancy of firecracker penstemon and secondary dormancy of `Bandera' penstemon. Our findings suggest that incubation below 20C, combined with 8 weeks of stratification or the use of after-ripened seed, may improve seed propagation efforts for these species.

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Non-Deep Simple Morphophysiological Dormancy and Germination Characteristics of Gentiana triflora var. japonica (Kusn.) H. Hara (Gentianaceae), a Rare Perennial Herb in Korea

Plants ◽

10.3390/plants10101979 ◽

2021 ◽

Vol 10 (10) ◽

pp. 1979

Author(s):

Hyeon-Min Kim ◽

Jun-Hyeok Kim ◽

Da-Hyun Lee ◽

Young-Ho Jung ◽

Chung-Youl Park ◽

...

Keyword(s):

Seed Germination ◽

Seed Dormancy ◽

Incubation Temperature ◽

Potassium Nitrate ◽

Perennial Herb ◽

Cold Stratification ◽

Gentiana Triflora ◽

Nitrate Treatment ◽

Morphophysiological Dormancy ◽

Seed Propagation

This study investigated the kind of seed dormancy and seed germination of Gentiana triflora var. japonica (Kusn.) H. Hara for developing a seed propagation method. The seeds were collected in October 2020 from plants at Mt. Sobaeksan, Korea. In a water imbibition experiment, seed weights increased by > 101.9% of their initial masses over 12 h. Effects of incubation temperature (5, 15, 20, 25, 15/6, or 25/15 °C), cold stratification period (5 °C; 0, 4, 8, or 12 weeks), and gibberellic acid (GA3; 0, 10, 100, or 1000 mg∙L−1) and potassium nitrate treatment (KNO3; 0, 1000, 2000, or 4000 mg∙L−1) on seed germination were investigated to characterize seed dormancy. These seeds exhibited underdeveloped embryos during seed dispersal. The seeds failed to reach the final germination of 15.0% after treatment at 5, 15, 20, 25, 15/6, or 25/15 °C. After cold stratification for 8 weeks, the germination increased dramatically by > 90.0% compared to that at 0 weeks. After the GA3 treatment, the germination reached > 80.0% within 5 days. The final germination was 90.0% in the 100 mg∙L−1 GA3 treatment group. However, the KNO3 treatment had no effect on seed germination. Therefore, the G. triflora var. japonica seeds exhibited non-deep simple morphophysiological dormancy.

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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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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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Germination Behavior of Rauvolfia serpentine (L.) Seeds with the use of Different Seed Treatments

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5624 ◽

2021 ◽

Author(s):

Amit Kumar Tiwari ◽

Prawal P.S. Verma ◽

Dipender Kumar ◽

Sonveer Singh ◽

Rakesh Kumar ◽

...

Keyword(s):

Seed Germination ◽

Seedling Growth ◽

Seed Treatment ◽

Inhibitory Effect ◽

Germination Percentage ◽

Hot Water ◽

Cotton Cloth ◽

Cow Dung ◽

Seed Treatments ◽

Seed Propagation

Background: Sarpagandha is an indigenous medicinal herb of Indian continent. It has many medicinal properties. Due to increasing demand of Sarpagandha, its exploitation is increasing continuously but for lack of cultivation, this plant has been listed in endangered category. Commercially, it is propagated through seeds but the main barrier of seed propagation is its irregular and low germination. Hence, the current study was undertaken to study the effect of growing media and seed treatment methods on seed germination and seedling growth of Sarpagandha to eliminate the inhibitory effect of the hard stony endocarp.Methods: Seed germination and seedling growth experiments of Sarpagandha were carried out with following different seed treatments, T1 (Control), T2 (Water soaking for 24 hours), T3 (water soaking for 48 hours), T4 (Water soaking for 24 hours + cotton cloth wrapping for 24 hours), T5 (GA3 200 ppm), T6 (FYM treatment for 24 hours), T7 (FYM treatment for 48 hours), T8 (Hot water treatment) and T9 (Cow dung treatment for 24 hours). Experiment was laid out in CRD. The data recorded on the various parameters were analyzed at 5% level of significance by using ANOVA.Result: Results indicated highest germination percentage (51), lowest mortality percent (49), minimum days for initiation of germination (23), minimum days taken for germination completion (33), highest speed of germination (3.77), maximum vigour index (1441.44), highest root (11.27 cm) and highest shoot length (17 cm) in T5 (GA3 200 ppm) followed by T3 (water soaking for 48 hours). Indicating, T5 (GA3 200 ppm) to be best seed treatment for higher germination and subsequent seedling growth of Sarpagandha (Rauvolfia serpentine L.).

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SEED GERMINATION OF GUNDELIA TOURNEFORTII L. UNDER DIFFERENT DORMANCY BREAKING TREATMENTS

PLANT ARCHIVES ◽

10.51470/plantarchives.2021.v21.no1.141 ◽

2021 ◽

Vol 21 (No 1) ◽

Author(s):

Vian Dler Ali ◽

Farhad Hassan Aziz

Keyword(s):

Seed Germination ◽

Tap Water ◽

Petri Dish ◽

Dry Weight ◽

Germination Percentage ◽

Dormancy Breaking ◽

Mean Germination Time ◽

Breaking Seed Dormancy ◽

Germination Value ◽

Peak Value

Gundelia tournefortii L. is adapted to mountains area climate, and the germination of this plant is not easily. This research conducted to study the effect of different seed treatments in various treatment durations in two experiments in petri dish in the laboratory and in seedling tray in the lath house to breaking seed dormancy and germination stimulus. Results indicated that there is significant enhancement of germination by all treatments and the maximum germination percentage was obtained by seed freezing 99.17% in the laboratory and 93.33% in the lath house for all treatment durations 12, 14, 48 and 72 hours. The other parameters of seed germination like germination speed, peak value, mean daily germination, mean germination time, germination value, radicle length, radicle elongation velocity, plumule length, plumule elongation velocity, seedling fresh and dry weight escalated by seed freezing and seed soaking in tap water at all soaking durations 12, 24, 48 and 72 hours. Gundelia tournefortii L. germinated seed was an anatomically examined by paraffin method and calculated diploid number of chromosomes 2n=2x=18 by aceto-carmine squash methods

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Sensitivity of Seed Germination to Temperature and Light in Helichrysum amorginum

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Horticulture ◽

10.15835/buasvmcn-hort:2020.0007 ◽

2020 ◽

Vol 77 (1) ◽

pp. 7

Author(s):

Sofia ARGYRIOU ◽

Panayiota PAPASTYLIANOU ◽

George STAVROPOULOS ◽

Angeliki KOUSTA ◽

Ioanna KAKABOUKI ◽

...

Keyword(s):

Seed Germination ◽

Seedling Survival ◽

Germination Percentage ◽

Effect Of Temperature ◽

Germination Time ◽

Randomized Design ◽

Perennial Shrub ◽

Mean Germination Time ◽

Lower Temperature ◽

Seed Propagation

Helichrysum amorginum is a perennial shrub, endemic on the Greek island of Amorgos and used for medicinal, cosmetic and ornamental purposes. Information concerning germination behavior and seedling survival is considered essential for the establishment and cultivation of wild species. The objective of this study was to investigate the effect of temperature and light on germination of Helichrysum amorginum seeds. A set of experiments was conducted under completely randomized design with four replications of 200 seeds at three different suboptimal germination temperatures (15, 20 and 25°C) in light and dark conditions for 10 days. Seed material was collected from two different fields of the island (Aegiali and Katapola). The germination performance was evaluated by final germination percentage and mean germination time. The effect of temperature on seed germination percentage and mean germination time was significant in all cases. The presence of light enhanced germination, especially at the optimum temperature of 20°C. In most cases the mean germination time increased at the lower temperature of 15°C. Seeds from Aegiali exhibited higher germination ability than the seed lot from Katapola. Knowledge of seed germination behaviour is of major importance in order to establish effective protocols for seed propagation in Helichrysum amorginum.

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Seed-germination response of Leymus chinensis to cold stratification in a range of temperatures, light and low water potentials under salt and drought stresses

Crop and Pasture Science ◽

10.1071/cp16402 ◽

2017 ◽

Vol 68 (2) ◽

pp. 188 ◽

Cited By ~ 7

Author(s):

Jixiang Lin ◽

Yujie Shi ◽

Shuang Tao ◽

Xingyang Yu ◽

Dafu Yu ◽

...

Keyword(s):

Drought Stress ◽

Seed Germination ◽

Drought Tolerance ◽

Northeast China ◽

Germination Percentage ◽

Leymus Chinensis ◽

Grass Species ◽

Cold Stratification ◽

Effective Measure ◽

Salt And Drought Stresses

Leymus chinensis has important forage value and is considered a useful grass species for grassland restoration in Northeast China. However, little information exists concerning the germination responses of this species to interactions of cold stratification, light, temperature and low water potential caused by salinity and drought. Experiments were conducted in growth chambers, and the results showed that in all conditions of light, temperature and water stresses, the germination percentages of cold-stratified seeds were higher than of non-stratified seeds. Light had an inhibitory effect on germination percentage under both non-saline and salt stress conditions; darkness is beneficial for germination of this species. In addition, seeds germinated much better under alternating temperature regimes than under constant temperatures. Both salt and drought stresses decreased the germination percentage of Leymus chinensis, but the reductions under drought stress were much greater. Moreover, after being transferred to distilled water, most non-germinated seeds under drought stress germinated well, and the total percentage reached that of the non-saline condition level. Therefore, cold stratification is an effective measure to increase seed germination and salt or drought tolerance, especially in darkness. We conclude that Leymus chinensis has definite salt and drought tolerance during the germination stage and it is a promising species for the restoration of deteriorated grassland in Northeast China.

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Effects of partial drying on seed germination in the aquatic grasses Zizania palustris L. and Porteresia coarctata (Roxb.) Tateoka

Seed Science Research ◽

10.1017/s0960258500001380 ◽

1992 ◽

Vol 2 (4) ◽

pp. 199-205 ◽

Cited By ~ 8

Author(s):

C. D. Aldridge ◽

R. J. Probert

Keyword(s):

Abscisic Acid ◽

Seed Germination ◽

Growth Regulators ◽

Germination Percentage ◽

Hormonal Status ◽

Cold Stratification ◽

Porteresia Coarctata ◽

Germination Response ◽

Fold Reduction ◽

Germination Behaviour

AbstractPartial drying of non-dormant seeds had little effect on germination behaviour compared with undried controls. In contrast, partial drying resulted in a marked increase in the germination response of freshly harvested (dormant) seeds of Z. palustris. Partial drying also resulted in a 100-fold reduction in the concentration of gibberellins (GA4+7) required for maximum germination. Although the concentration range of applied abscisic acid (ABA) that permitted germination was unaltered, partial drying increased the final germination percentage at all concentrations tested. The concentration of ABA above which germination was reduced in freshly harvested (dormant) seeds of Z. palustris was 3.16 × 10−7m compared with 10−4m in fresh (non-dormant) seeds of P. coarctata. Changes in the germination response of Z. palustris seeds to applied growth regulators, following partial drying or cold stratification might be explained by similar changes in hormonal status.

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Seed germination of Paederotella pontica (Rupr. ex Boiss.) Kem-Nath.- rare endemic species of the Caucasus

BIO Web of Conferences ◽

10.1051/bioconf/20202400077 ◽

2020 ◽

Vol 24 ◽

pp. 00077

Author(s):

Nana Shakarishvili

Keyword(s):

Seed Germination ◽

Tetrazolium Salt ◽

Cold Stratification ◽

Dormancy Breaking ◽

Treatment Results ◽

Relict Species ◽

The Caucasus ◽

Narrow Endemic ◽

Dry Storage ◽

Rare Endemic

Paederotella pontica is a Colchis tertiary relict species, regional narrow endemic to the Caucasus, representative of an oligotypic genus. The aim of this study was to determine dormancy-breaking requirements and develop seed germination protocol for P. pontica. Freshly matured seeds of P. pontica are morphophysiologically dormant (MPD). Mean length of seed is 820 μm, linear embryo is fully differentiated, on average 625 μm long. Penetration of tetrazolium salt indicates the permeability of seed coat and high percentage of vital seeds in capsules. Prior to root emergence, the E:S ratio increased from 0.76 to 0.9. Effects of warm and cold stratification and gibberellic acid (GA3) on embryo growth and seed germination were studied under laboratory conditions. Since cold stratification is the only requirement for the loss of MPD, the longest embryo growth occurred during this treatment and GA3 promoted MPD loss, we concluded that P. pontica seeds have intermediate complex MPD. Based on the treatment results a germination protocol is proposed: 1. Dry storage at 20°C, 2 months; 2. Cold-wet stratification at 3°C, 3 months; 3. Germination at 20/15°C day/night. Under developed conditions germination is fast, synchronous and yields to 80%.

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