Effects of pre-chilling, incubation temperature and light on seed germination of Saponaria officinalis

Various environmental factors were tested under laboratory conditions to determine their effects on germination of seeds of prickly sida (Sida spinosaL. ♯3SIDSP). Neither freezing and thawing nor moist chilling at 5 C promoted seed germination. However, increasing the incubation temperature and subjecting seeds to wet-dry cycles enhanced germination; high temperatures were more effective than alternate wetting and drying. Shifting seeds from a lower to a higher temperature regime increased germination. Seeds shifted from 15/6, 20/10, 25/15, or 30/15 C to higher regimes of 20/10, 25/15, 30/15, 35/20, or 40/25 C germinated to greater percentages than did seeds kept continuously at the lower thermoperiods. With an increase in length of time seeds were at a lower temperature, there was an increase in the percentage that germinated after they were moved to a higher regime.

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Seed germination of Solanum spp. (Solanaceae) for use in rehabilitation and commercial industries

Australian Journal of Botany ◽

10.1071/bt07209 ◽

2008 ◽

Vol 56 (4) ◽

pp. 333 ◽

Cited By ~ 20

Author(s):

L. E. Commander ◽

D. J. Merritt ◽

D. P. Rokich ◽

G. R. Flematti ◽

K. W. Dixon

Keyword(s):

Seed Germination ◽

Food Industry ◽

Incubation Temperature ◽

Solanum Species ◽

Seed Embryo ◽

Physiological Dormancy ◽

Incubation Temperatures ◽

Smoke Water ◽

Solanum Spp ◽

Seeds Germination

Effective methods for propagation of native Solanum species are required for mine rehabilitation and the native food industry in Australia. This study investigated seed germination of eight native Solanum species with respect to incubation temperature and the efficacy of germination-promoting compounds gibberellic acid (GA3), the butenolide isolated from smoke (karrikinolide, KAR1) and smoke water (SW). Seeds of all species were tested under a temperature regime of 26/13°C or 33/18°C. In these conditions, seeds of only two species, S. cunninghamii Benth. and S. phlomoides Benth. germinated to high levels without treatment. Of the remaining six species, GA3 alone promoted germination in S. chippendalei Symon, S. diversiflorum F.Muell. and S. sturtianum F.Muell., whereas GA3, KAR1 and SW were effective at promoting germination of S. centrale J.M.Black, S. dioicum W.Fitzg. and S. orbiculatum Dunal ex Poir. to varying degrees. Additional incubation temperatures (10, 15, 20, 25 and 30°C) were examined for S. centrale and S. orbiculatum. For both species, broadly similar patterns were noted in the response of seeds to GA3, KAR1 and SW across all temperatures. However, for S. centrale seeds, germination percentages were higher at 26/13°C than at any of the constant temperatures, and there was a trend of increasing germination with increasing constant temperature for S. orbiculatum seeds. Analysis of seed embryo type and imbibition characteristics and consideration of the subsequent germination results indicates that dormant Solanum seeds possess physiological dormancy.

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Temperature Requirements for Seed Germination of Three Penstemon Species'

HortScience ◽

10.21273/hortsci.25.2.191 ◽

1990 ◽

Vol 25 (2) ◽

pp. 191-193 ◽

Cited By ~ 9

Author(s):

Phil S. Allen ◽

Susan E. Meyer

Keyword(s):

Seed Germination ◽

Incubation Temperature ◽

Marked Decrease ◽

Rocky Mountain ◽

Germination Percentage ◽

Cold Stratification ◽

Dormancy Breaking ◽

Primary Dormancy ◽

Temperature Requirements ◽

Seed Propagation

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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Seed Germination and Seedling Growth of the Endangered Azorean Cherry Prunus azorica

HortScience ◽

10.21273/hortsci.47.9.1222 ◽

2012 ◽

Vol 47 (9) ◽

pp. 1222-1227 ◽

Cited By ~ 8

Author(s):

Orlanda Cristina Barros Moreira ◽

José Martins ◽

Luís Silva ◽

Mónica Moura

Keyword(s):

Seed Germination ◽

Growth Regulator ◽

Incubation Temperature ◽

Seed Morphology ◽

Laurel Forest ◽

Life Project ◽

Temperature Regimes ◽

Physiological Dormancy ◽

Priority Species ◽

Alternating Temperature

Prunus azorica is an Azorean endemic tree considered as a priority species for conservation. It is important as a laurel forest component, particularly at medium altitude, and as a food source for the endangered bird Pyrrhula murina. The best conditions for seed germination were investigated after removal of the outer layers of the fruit by determining the effect of 1) using stones or seeds; 2) stratification regime (six treatments and a control); 3) incubation temperature (four alternating temperature regimes); and 4) gibberellic acid concentration (three levels). This resulted in a fully factorial design with 168 (2 × 7 × 4 × 3) treatments with three replicates per treatment and 25 seeds per replicate. Cumulative germination percentages were determined at the end of the trial. Globally, there was a significant effect of endocarp removal (49% germination with seeds and 15% with stones). Both for stones and seeds, there was a significant effect of incubation temperature, stratification regime, and growth regulator concentration. Stones attained a maximum germination of ≈80% under several stratification treatments including cold (4 °C) or warm (20 °C) followed by cold and at 10/5 °C without the addition of a growth regulator. Seeds attained a maximum germination of greater than 90% without stratification at 10/5 or 15/10 °C without the addition of a growth regulator. During the stratification process, germination occurred only for seeds, particularly for longer treatments, for example, those corresponding to 3 or more months of stratification, including warm followed by cold (75% to 80%) or cold alone (77%). According to seed morphology and germination results, the seed appears to have a non-deep physiological dormancy. Seeds of P. azorica can thus be efficiently germinated after endocarp removal at temperatures of 10/5 or 15/10 °C with a daily light period of 12 hours. This protocol allowed producing hundreds of viable seedlings that were used in the reforestation of a laurel forest stand in a LIFE project.

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Molecular aspects during seed germination of Erythrina velutina Willd. under different temperatures (Part 1): reserve mobilization

Journal of Seed Science ◽

10.1590/2317-1545v42239839 ◽

2020 ◽

Vol 42 ◽

Author(s):

Francival Cardoso Felix ◽

Josenilda Aprígio Dantas de Medeiros ◽

Cibele dos Santos Ferrari ◽

Mauro Vasconcelos Pacheco ◽

Salvador Barros Torres

Keyword(s):

Thermal Stress ◽

Seed Germination ◽

Seedling Establishment ◽

Incubation Temperature ◽

Northeastern Brazil ◽

Reserve Mobilization ◽

Social Ecological ◽

Different Temperatures ◽

Molecular Aspects ◽

Germination Vigor

ABSTRACT: Erythrina velutina Willd. (Fabaceae) is a tree species that bears social, ecological, and economic importance for northeastern Brazil, a region with frequent temperature variations. The objective of this work was to evaluate the mobilization of reserves during seed germination and seedling establishment of E. velutina at different temperatures, and how these mechanisms are affected in a thermal-stress situation. The seeds germinated at 5, 15, 25, 35, and 45 °C, and the physiological and biochemical aspects of reserve mobilization (starch, lipids, and total proteins) were assessed during seedling establishment. Germination, vigor, and the mobilization of reserves from the cotyledons to the embryonic axis are affected according to the incubation temperature. The temperature of 25 °C favors the mobilization of reserves during seed germination and seedling establishment in E. velutina. In a situation of thermal stress, high temperatures affect the establishment of the seedlings, whereas low temperatures compromise the mobilization of reserves.

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Effects of Salinity, Temperature, and pH on Germination of Echinacea angustifolia Seeds

HortScience ◽

10.21273/hortsci.30.4.869f ◽

1995 ◽

Vol 30 (4) ◽

pp. 869F-869

Author(s):

Kyu-Min Lee ◽

Qudsia Hussaini ◽

Shanqiang Ke ◽

Chiwon W. Lee

Keyword(s):

Seed Germination ◽

Incubation Temperature ◽

Echinacea Angustifolia ◽

Nacl Concentration ◽

Percent Germination ◽

Petri Dishes ◽

Ph Range

The influences of NaCl concentration, incubation temperature, and pH on the germination of Echinacea angustifolia seeds were investigated. Dehulled, surface-disinfected seeds were germinated in petri dishes containing 0, 0.5, 1, 1.5, 2.0, 2.5, 3.0, 3.5, or 4.0 g–liter–1 NaCl at 12, 17, 22, or 27C for 10 days. Percent seed germination was the highest at 0 ppm NaCl and was progressively reduced as NaCI concentrations increased to 4 g–liter–1 at all temperatures. The NaCI suppression of germination was most severe when seeds were incubated at 27C. No germination occurred at 12C. When seeds were germinated over a pH range from 4 to 11, the highest percent germination occurred at pHs between 6 and 8 at 25C.

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Milk Thistle(Silybum marianum)Seed Germination

Weed Science ◽

10.1017/s0043174500050189 ◽

1978 ◽

Vol 26 (4) ◽

pp. 395-398 ◽

Cited By ~ 14

Author(s):

J. A. Young ◽

R. A. Evans ◽

R. B. Hawkes

Keyword(s):

Seed Germination ◽

Incubation Temperature ◽

Potassium Nitrate ◽

Milk Thistle ◽

Burial Depth ◽

Silybum Marianum ◽

Temperature Range ◽

Germination Temperature ◽

Time Required ◽

Incubation Temperatures

The germination of seeds (achenes) of milk thistle [Silybum marianum(L.) Gaertn.] was investigated. One month after harvest, milk thistle seeds had afterripening requirements related to germination temperature that limited germination to 10 to 20 C temperatures. The time required to satisfy afterripening requirements was dependent on germination temperature. Generally the higher the incubation temperature during germination, the longer the afterripening requirement (up to a maximum of 5 months). Once afterripening requirements were satisfied, milk thistle seeds germinated over a temperature range of from 0 to 30 C. Optimum germination occurred with 2 to 15 C 16-h cold periods alternating with 10 to 30 C 8-h warm periods. Emergence of milk thistle seedlings decreased with increased burial depth, but substantial emergence occurred from 8 cm. Germination on the surface of the soil or litter was greatly reduced compared to that with slight soil or litter coverage. Potassium nitrate (KNO3) added to the germination substrate at 1.0 mM enhanced the germination of milk thistle seeds at 2 and 5 C incubation temperatures.

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Effects of Incubation Temperature on Seed Germination of Mediterranean Plants with Different Geographical Distribution Ranges

Folia Geobotanica ◽

10.1007/s12224-011-9110-0 ◽

2011 ◽

Vol 47 (1) ◽

pp. 17-27 ◽

Cited By ~ 27

Author(s):

Belén Luna ◽

Beatriz Pérez ◽

Iván Torres ◽

José Manuel Moreno

Keyword(s):

Seed Germination ◽

Geographical Distribution ◽

Incubation Temperature ◽

Mediterranean Plants ◽

Distribution Ranges

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Assessing tree germination resilience to global warming: a manipulative experiment using sugar maple (Acer saccharum)

Seed Science Research ◽

10.1017/s0960258516000040 ◽

2016 ◽

Vol 26 (2) ◽

pp. 153-164 ◽

Cited By ~ 13

Author(s):

Kevin A. Solarik ◽

Dominique Gravel ◽

Aitor Ameztegui ◽

Yves Bergeron ◽

Christian Messier

Keyword(s):

Seed Germination ◽

Constant Temperature ◽

Climate Warming ◽

Acer Saccharum ◽

Sugar Maple ◽

Incubation Temperature ◽

Germination Percentage ◽

Seed Sources ◽

Seed Origin ◽

Maple Seed

AbstractA climate warming of 2–5°C by the end of the century will impact the likelihood of seed germination of sugar maple (Acer saccharum), a dominant tree species which possesses a restricted temperature range to ensure successful reproduction. We hypothesize that seed origin affects germination due to the species' local adaptation to temperature. We tested this by experimentally investigating the effect of incubation temperature and temperature shifting on sugar maple seed germination from seven different seed sources representing the current species range. Survival analysis showed that seeds from the northern range had the highest germination percentage, while the southern range had the lowest. The mean germination percentage under constant temperatures was best when temperatures were ≤5°C, whereas germination percentages plummeted at temperatures ≥11°C (5.8%). Cool shifting increased germination by 19.1% over constant temperature treatments and by 29.3% over warm shifting treatments. Both shifting treatments caused earlier germination relative to the constant temperature treatments. A climate warming of up to +5°C is shown to severely reduce germination of seeds from the southern range. However, under a more pronounced warming of 7°C, seed germination at the northern range become more affected and now comparable to those found from the southern range. This study states that the high seed germination percentage found in sugar maple at the northern range makes it fairly resilient to the warmest projected temperature increase for the next century. These findings provide forest managers with the necessary information to make accurate projections when considering strategies for future regeneration while also considering climate warming.

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Bromus tectorum seed germination: between-population and between-year variation

Canadian Journal of Botany ◽

10.1139/b96-109 ◽

1996 ◽

Vol 74 (6) ◽

pp. 875-882 ◽

Cited By ~ 52

Author(s):

Julie Beckstead ◽

Susan E. Meyer ◽

Phil S. Allen

Keyword(s):

Seed Germination ◽

Bromus Tectorum ◽

Incubation Temperature ◽

Weather Conditions ◽

Germination Percentage ◽

Maximum Temperature ◽

Germination Time ◽

Germination Response ◽

Mean Germination Time ◽

Contrasting Habitats

Cheatgrass (Bromus tectorum L., Poaceae), an introduced winter annual, has invaded a variety of habitats in western North America. This study examines variation in cheatgrass germination response and after-ripening patterns that are related to differences in habitat and to yearly differences in weather conditions during seed maturation. Seeds collected from five contrasting populations in 1992 and 1993 were subjected to controlled dry storage and then incubated across a range of temperatures. Recently harvested seeds were dormant and germinated slowly, while fully after-ripened seeds were nondormant and germinated rapidly. The optimal incubation temperature for mean germination time shifted from 5:15 to 20:30 °C as a result of after-ripening. Between-population differences in germination response appear to be related to the potential risk of precocious summer germination. The results from this 2-year study suggest that the more extreme yet predictable environments select for seed germination and after-ripening patterns that are genetically fixed, while populations from more favorable environments tended to show more between-year variations, suggesting more phenotypic plasticity. Germination percentage showed greater between-year variation than mean germination time. Between-year differences could not be explained simply by differences in maximum temperature or total precipitation during maturation. Adaptive germination responses in cheatgrass populations from contrasting habitats may have both genetic and environmental components, thus explaining why this species can become established in such a variety of habitats. Keywords: after-ripening, invading species, dormancy, mean germination time, cheatgrass, downy brome.

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