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Charles C. Baskin - One of the best experts on this subject based on the ideXlab platform.
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Dormancy Breaking and germination requirements of seeds of the hawaiian endemic dianella sandwicensis xanthorrhoeaceae
Australian Journal of Botany, 2018Co-Authors: Dustin Wolkis, Charles C. Baskin, Jeremy M BaskinAbstract:One problem with including some wild plant species in restoration projects is that seeds are dormant and fail to germinate. Thus, information on the Dormancy-Breaking and germination requirements facilitates propagation of species, such as the Hawaiian endemic Dianella sandwicensis Hook. & Arn., for conservation. In seeds of this species the embryo is shorter than the endosperm, and seeds sown in early summer in Hawai‘i did not germinate until autumn. Thus, we hypothesised that seeds have morphophysiological Dormancy (MPD) and that germination is promoted by low (autumn) temperatures. Studies on embryo growth and the temperature requirements for Dormancy-break and germination were conducted on seeds of D. sandwicensis collected on three Hawaiian Islands. Prior to germination the embryo length : seed length ratio increased 16.3 to 17.6%; thus, seeds have MPD. Since both embryo growth and germination occurred at 25/15°C, seeds have a simple level of MPD. Seeds germinated to 90–100% at both 20/10 and 25/15°C, but germination was faster at 20/10°C. However, seeds incubated for 12 weeks at 25/15°C then moved to 20/10°C reached 100% germination as rapidly as seeds kept at 20/10°C. Our results show that exposure of seeds to relatively cool autumn (20/10°C) conditions facilitates propagation of this species from seeds.
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seed Dormancy and Dormancy Breaking methods in leymus chinensis trin tzvel poaceae
Grass and Forage Science, 2016Co-Authors: Charles C. Baskin, Jeremy M Baskin, X Q He, Yan Rong Wang, Xiaowen Hu, Y Y LvAbstract:Leymus chinensis (Trin.) Tzvel. is a perennial grass with high productivity and forage value; however, poor stand establishment, often due to seed Dormancy, limits its widespread use for forage production. To investigate the mechanism of seed Dormancy and to develop effective methods of improving germination, the contribution of each part of the caryopsis to Dormancy was investigated, and a number of single or combined Dormancy-Breaking pre-treatments were conducted using three seed lots. The palea, lemma, pericarp/testa, and endosperm all contributed to seed Dormancy. The contribution of each part to Dormancy was 23·4%, lemma; 6·2%, palea; 28·4%, pericarp/testa; and 42·0%, endosperm. Hull (palea and lemma) removal, pericarp/testa piercing, and soaking in distilled water or 30% sodium hydroxide (NaOH) significantly decreased the percentage of dormant seeds (i.e. increased germination). Treating hull-removed and pericarp/testa-pierced seeds with gibberellic acid (GA3) also significantly decreased the percentage of dormant seeds. Compared with each of the single pre-treatments, the combined pre-treatment of pre-soaking in water for 1 d, then 30% NaOH for 60 min and treating with 300 μm GA3 resulted in the highest germination (89%); and seed viability was 91%.
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A proposed mechanism for physical Dormancy break in seeds of Ipomoea lacunosa (Convolvulaceae).
Annals of Botany, 2008Co-Authors: K. M. G. Gehan Jayasuriya, Robert L Geneve, Jeremy M Baskin, Charles C. BaskinAbstract:Background and Aims The water-impermeable seeds of Ipomoea lacunosa undergo sensitivity cycling to Dormancy Breaking treatment, and slits are formed around bulges adjacent to the micropyle during Dormancy break, i.e. the water gap opens. The primary aim of this research was to identify the mechanism of slit formation in seeds of this species.
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physical Dormancy in seeds of the holoparasitic angiosperm cuscuta australis convolvulaceae cuscuteae Dormancy Breaking requirements anatomy of the water gap and sensitivity cycling
Annals of Botany, 2008Co-Authors: K Gehan M G Jayasuriya, Charles C. Baskin, Jeremy M Baskin, Robert L Geneve, Chingte ChienAbstract:BACKGROUND AND AIMS: Dormancy in seeds of Cuscuta (Convolvulaceae, tribe Cuscuteae) is due to a water-impermeable seed coat (physical Dormancy). In nondormant seeds of several species of this family, bulges adjacent to the micropyle have been identified as the initial route of water entry into seeds (water gap). However, there are claims that water enters seeds of Cuscuta spp. via the entire seed coat. Although several studies have been done on seed coat anatomy of Cuscuta, none has identified and/or characterized the morphology/anatomy of a water gap. Thus, the primary aim of this research was to identify and describe the morphology and anatomy of the water gap in seeds of Cuscuta australis. It was also determined if sensitivity cycling to Dormancy-Breaking treatments occurs in seeds of this species. METHODS: Light microscopy, scanning electron microscopy, tissue-sectioning and dye-tracking and blocking experiments were used to investigate the morphology and anatomy of the water gap. Treatments simulating natural conditions were used to break seed Dormancy. Storage of seeds at different temperatures was tested for their effect on sensitivity to Dormancy-Breaking treatment. KEY RESULTS: Dormancy-Breaking treatments caused the tightly closed hilar fissure to open. Staining was observed in cells below the hilum area but not in those below the seed coat away from the hilum. Sensitivity to Dormancy-Breaking treatment was induced by storing seeds dry and reduced by storing them wet. CONCLUSIONS: Whereas bulges adjacent to the micropyle act as the water gap in other species of Convolvulaceae with physical Dormancy, the hilar fissure serves this function in Cuscuta. Cuscuta australis can cycle between insensitivity sensitivity to Dormancy-Breaking treatments.
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Dormancy Breaking and germination requirements for seeds of symphoricarpos orbiculatus caprifoliaceae
American Journal of Botany, 2001Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract:Fruits (drupes) of Symphoricarpos orbiculatus ripen in autumn and are dispersed from autumn to spring. Seeds (true seed plus fibrous endocarp) are dormant at maturity, and they have a small, linear embryo that is underdeveloped. In contrast to previous reports, the endocarp and seed coat of S. orbiculatus are permeable to water; thus, seeds do not have physical Dormancy. No fresh seeds germinated during 2 wk of incubation over a 158/68‐358/208C range of thermoperiods in light (14-h photoperiod); gibberellic acid and warm or cold stratification alone did not overcome Dormancy. One hundred percent of the seeds incubated in a simulated summer→ autumn → winter → spring sequence of temperature regimes germinated, whereas none of those subjected to a winter → spring sequence did so. That is, cold stratification is effective in Breaking Dormancy only after seeds first are exposed to a period of warm temperatures. Likewise, embryos grew at cold temperatures only after seeds were exposed to warm temperatures. Thus, the seeds of S. orbiculatus have nondeep complex morphophysiological Dormancy. As a result of dispersal phenology and Dormancy-Breaking requirements, in nature most seeds that germinate do so the second spring following maturity; a low to moderate percentage of the seeds may germinate the third spring. Seeds can germinate to high percentages under Quercus leaf litter and while buried in soil; they have little or no potential to form a long-lived soil seed bank.
Jeremy M Baskin - One of the best experts on this subject based on the ideXlab platform.
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Dormancy Breaking and germination requirements of seeds of the hawaiian endemic dianella sandwicensis xanthorrhoeaceae
Australian Journal of Botany, 2018Co-Authors: Dustin Wolkis, Charles C. Baskin, Jeremy M BaskinAbstract:One problem with including some wild plant species in restoration projects is that seeds are dormant and fail to germinate. Thus, information on the Dormancy-Breaking and germination requirements facilitates propagation of species, such as the Hawaiian endemic Dianella sandwicensis Hook. & Arn., for conservation. In seeds of this species the embryo is shorter than the endosperm, and seeds sown in early summer in Hawai‘i did not germinate until autumn. Thus, we hypothesised that seeds have morphophysiological Dormancy (MPD) and that germination is promoted by low (autumn) temperatures. Studies on embryo growth and the temperature requirements for Dormancy-break and germination were conducted on seeds of D. sandwicensis collected on three Hawaiian Islands. Prior to germination the embryo length : seed length ratio increased 16.3 to 17.6%; thus, seeds have MPD. Since both embryo growth and germination occurred at 25/15°C, seeds have a simple level of MPD. Seeds germinated to 90–100% at both 20/10 and 25/15°C, but germination was faster at 20/10°C. However, seeds incubated for 12 weeks at 25/15°C then moved to 20/10°C reached 100% germination as rapidly as seeds kept at 20/10°C. Our results show that exposure of seeds to relatively cool autumn (20/10°C) conditions facilitates propagation of this species from seeds.
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seed Dormancy and Dormancy Breaking methods in leymus chinensis trin tzvel poaceae
Grass and Forage Science, 2016Co-Authors: Charles C. Baskin, Jeremy M Baskin, X Q He, Yan Rong Wang, Xiaowen Hu, Y Y LvAbstract:Leymus chinensis (Trin.) Tzvel. is a perennial grass with high productivity and forage value; however, poor stand establishment, often due to seed Dormancy, limits its widespread use for forage production. To investigate the mechanism of seed Dormancy and to develop effective methods of improving germination, the contribution of each part of the caryopsis to Dormancy was investigated, and a number of single or combined Dormancy-Breaking pre-treatments were conducted using three seed lots. The palea, lemma, pericarp/testa, and endosperm all contributed to seed Dormancy. The contribution of each part to Dormancy was 23·4%, lemma; 6·2%, palea; 28·4%, pericarp/testa; and 42·0%, endosperm. Hull (palea and lemma) removal, pericarp/testa piercing, and soaking in distilled water or 30% sodium hydroxide (NaOH) significantly decreased the percentage of dormant seeds (i.e. increased germination). Treating hull-removed and pericarp/testa-pierced seeds with gibberellic acid (GA3) also significantly decreased the percentage of dormant seeds. Compared with each of the single pre-treatments, the combined pre-treatment of pre-soaking in water for 1 d, then 30% NaOH for 60 min and treating with 300 μm GA3 resulted in the highest germination (89%); and seed viability was 91%.
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A proposed mechanism for physical Dormancy break in seeds of Ipomoea lacunosa (Convolvulaceae).
Annals of Botany, 2008Co-Authors: K. M. G. Gehan Jayasuriya, Robert L Geneve, Jeremy M Baskin, Charles C. BaskinAbstract:Background and Aims The water-impermeable seeds of Ipomoea lacunosa undergo sensitivity cycling to Dormancy Breaking treatment, and slits are formed around bulges adjacent to the micropyle during Dormancy break, i.e. the water gap opens. The primary aim of this research was to identify the mechanism of slit formation in seeds of this species.
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physical Dormancy in seeds of the holoparasitic angiosperm cuscuta australis convolvulaceae cuscuteae Dormancy Breaking requirements anatomy of the water gap and sensitivity cycling
Annals of Botany, 2008Co-Authors: K Gehan M G Jayasuriya, Charles C. Baskin, Jeremy M Baskin, Robert L Geneve, Chingte ChienAbstract:BACKGROUND AND AIMS: Dormancy in seeds of Cuscuta (Convolvulaceae, tribe Cuscuteae) is due to a water-impermeable seed coat (physical Dormancy). In nondormant seeds of several species of this family, bulges adjacent to the micropyle have been identified as the initial route of water entry into seeds (water gap). However, there are claims that water enters seeds of Cuscuta spp. via the entire seed coat. Although several studies have been done on seed coat anatomy of Cuscuta, none has identified and/or characterized the morphology/anatomy of a water gap. Thus, the primary aim of this research was to identify and describe the morphology and anatomy of the water gap in seeds of Cuscuta australis. It was also determined if sensitivity cycling to Dormancy-Breaking treatments occurs in seeds of this species. METHODS: Light microscopy, scanning electron microscopy, tissue-sectioning and dye-tracking and blocking experiments were used to investigate the morphology and anatomy of the water gap. Treatments simulating natural conditions were used to break seed Dormancy. Storage of seeds at different temperatures was tested for their effect on sensitivity to Dormancy-Breaking treatment. KEY RESULTS: Dormancy-Breaking treatments caused the tightly closed hilar fissure to open. Staining was observed in cells below the hilum area but not in those below the seed coat away from the hilum. Sensitivity to Dormancy-Breaking treatment was induced by storing seeds dry and reduced by storing them wet. CONCLUSIONS: Whereas bulges adjacent to the micropyle act as the water gap in other species of Convolvulaceae with physical Dormancy, the hilar fissure serves this function in Cuscuta. Cuscuta australis can cycle between insensitivity sensitivity to Dormancy-Breaking treatments.
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Dormancy Breaking and germination requirements for seeds of symphoricarpos orbiculatus caprifoliaceae
American Journal of Botany, 2001Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract:Fruits (drupes) of Symphoricarpos orbiculatus ripen in autumn and are dispersed from autumn to spring. Seeds (true seed plus fibrous endocarp) are dormant at maturity, and they have a small, linear embryo that is underdeveloped. In contrast to previous reports, the endocarp and seed coat of S. orbiculatus are permeable to water; thus, seeds do not have physical Dormancy. No fresh seeds germinated during 2 wk of incubation over a 158/68‐358/208C range of thermoperiods in light (14-h photoperiod); gibberellic acid and warm or cold stratification alone did not overcome Dormancy. One hundred percent of the seeds incubated in a simulated summer→ autumn → winter → spring sequence of temperature regimes germinated, whereas none of those subjected to a winter → spring sequence did so. That is, cold stratification is effective in Breaking Dormancy only after seeds first are exposed to a period of warm temperatures. Likewise, embryos grew at cold temperatures only after seeds were exposed to warm temperatures. Thus, the seeds of S. orbiculatus have nondeep complex morphophysiological Dormancy. As a result of dispersal phenology and Dormancy-Breaking requirements, in nature most seeds that germinate do so the second spring following maturity; a low to moderate percentage of the seeds may germinate the third spring. Seeds can germinate to high percentages under Quercus leaf litter and while buried in soil; they have little or no potential to form a long-lived soil seed bank.
Ganesha S Liyanage - One of the best experts on this subject based on the ideXlab platform.
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Do Dormancy-Breaking temperature thresholds change as seeds age in the soil seed bank?
Seed Science Research, 2016Co-Authors: Ganesha S LiyanageAbstract:In fire-prone ecosystems, many species regenerate after fire from persistent soil seed banks. Species with physically dormant (PY) seeds have Dormancy broken by fire-related heat. The magnitude of post-fire recruitment, to predict response to varying fire severity, is commonly estimated by testing Dormancy-Breaking temperature thresholds of fresh PY seeds. However, seeds spend years in the soil during the inter-fire period, and determining whether Dormancy-Breaking thresholds change over time is essential to accurately predict population persistence. Germination of four south-eastern Australian PY species from the Fabaceae family ( Acacia linifolia, Aotus ericoides, Bossiaea heterophylla and Viminaria juncea ) were studied. Dormancy-Breaking temperature thresholds vary inter-specifically and the species represented either high or low Dormancy-Breaking threshold classes. Freshly collected seeds, and seeds that had been buried in the field or stored in dry laboratory conditions for 6 and 18 months were subjected to a fire-related range of heat treatments (40–100°C). Seed ageing increased germination response to heat treatments, effectively lowering the Dormancy-Breaking thresholds of three species. The fourth species, A. linifolia , initially had a relatively large non-dormant fraction which was lost as seeds aged, with older seeds then displaying PY broadly similar to the other study species. Patterns of threshold decay were species-specific, with the thresholds and viability of low-threshold species declining more rapidly than high-threshold species. The non-dormant fraction did not increase over time for any of our study species. Instead of increasing their non-dormant fraction, as is common in other vegetation types, these fire-prone PY species displayed a change of Dormancy-Breaking temperature thresholds. This is an important distinction, as maintaining Dormancy during the inter-fire period is essential for population persistence. While changes in sensitivity to Dormancy-Breaking treatments have previously been reported as seeds age, our study provides the first test of changes to temperature thresholds, which increases the range of germination response from the seed bank under varying fire severity.
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intra population level variation in thresholds for physical Dormancy Breaking temperature
Annals of Botany, 2015Co-Authors: Ganesha S LiyanageAbstract:Background and Aims Intra-population variation in seed Dormancy is an advantage for population persistence in unpredictable environments. The important role played by physically dormant species in these habitats makes understanding the level of variation in their Dormancy a key ecological question. Heat produced in the soil is the major Dormancy-Breaking stimulus and, in fire prone ecosystems, soil temperatures generated by fire may vary spatially and over time. While many studies have investigated variation in initial Dormancy, a measure that is of little value in fire-prone ecosystems, where initial Dormancy levels are uniformly high, intra-population variation in Dormancy-Breaking temperature thresholds has never been quantified. This study predicted that species would display variation in Dormancy-Breaking temperature thresholds within populations, and investigated whether this variation occurred between individual plants from the same maternal environment. Methods The intra-population variation in Dormancy-Breaking thresholds of five common physically dormant shrub species (family Fabaceae) from fire-prone vegetation in south-eastern Australia was assessed using heat treatments and germination trials. Replicate batches of seeds from each of four maternal plants of Dillwynia floribunda, Viminaria juncea, Bossiaea heterophylla, Aotus ericoides and Acacia linifolia were treated at 40, 60, 80, 100 and 120 °C. Key Results Dormancy-Breaking response to heat treatments varied significantly among individual plants for all species, with some individuals able to germinate after heating at low temperatures and others restricting germination to temperatures that only occur as a result of high-severity fires. Germination rate (T50) varied among individuals of three species. Conclusions Variation detected among individuals that were in close proximity to each other indicates that strong differences in Dormancy-Breaking temperature thresholds occur throughout the broader population. Differences found at the individual plant level could contribute to subsequent variation within the seed bank, providing a bet-hedging strategy, and represent a mechanism for increasing the probability of population persistence in the face of fire regime variability.
Siti N Hidayati - One of the best experts on this subject based on the ideXlab platform.
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Dormancy Breaking and germination requirements for seeds of symphoricarpos orbiculatus caprifoliaceae
American Journal of Botany, 2001Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract:Fruits (drupes) of Symphoricarpos orbiculatus ripen in autumn and are dispersed from autumn to spring. Seeds (true seed plus fibrous endocarp) are dormant at maturity, and they have a small, linear embryo that is underdeveloped. In contrast to previous reports, the endocarp and seed coat of S. orbiculatus are permeable to water; thus, seeds do not have physical Dormancy. No fresh seeds germinated during 2 wk of incubation over a 158/68‐358/208C range of thermoperiods in light (14-h photoperiod); gibberellic acid and warm or cold stratification alone did not overcome Dormancy. One hundred percent of the seeds incubated in a simulated summer→ autumn → winter → spring sequence of temperature regimes germinated, whereas none of those subjected to a winter → spring sequence did so. That is, cold stratification is effective in Breaking Dormancy only after seeds first are exposed to a period of warm temperatures. Likewise, embryos grew at cold temperatures only after seeds were exposed to warm temperatures. Thus, the seeds of S. orbiculatus have nondeep complex morphophysiological Dormancy. As a result of dispersal phenology and Dormancy-Breaking requirements, in nature most seeds that germinate do so the second spring following maturity; a low to moderate percentage of the seeds may germinate the third spring. Seeds can germinate to high percentages under Quercus leaf litter and while buried in soil; they have little or no potential to form a long-lived soil seed bank.
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Dormancy Breaking and germination requirements of seeds of four lonicera species caprifoliaceae with underdeveloped spatulate embryos
Seed Science Research, 2000Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract:Dormancy-Breaking requirements and types of Dormancy were determined for seeds of Lonicera fragrantissima Lindl. & Paxt., L. japonica Thunb., L. maackii (Rupr.) Maxim. and L. morrowii A. 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 (GA 3 ) (tested only in the light) was more effective in Breaking Dormancy in L. maackii and L. morrowii than in L. fragrantissima and L. japonica . Warm- followed by cold stratification was required to break Dormancy in seeds of L. fragrantissima , whereas seeds of L. japonica required cold stratification only. Thus, seeds of L. fragrantissima have deep simple morphophysiological Dormancy (MPD) and those of L. japonica nondeep simple MPD. About 50%of the seeds of L. maackii required warm- or cold stratification only to come out of Dormancy and 50% of those of L. morrowii required 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 of L. japonica , L. maackii , and L. morrowii generally germinated to significantly higher percentages in light than in darkness; seeds of L. fragrantissima were not tested in darkness. Peaks of germination for seeds of L. fragrantissima , L. japonica , L. maackii and L. morrowii sown on a soil surface and covered with Quercus leaves 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 four Lonicera species.
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Dormancy Breaking and germination requirements for seeds of diervilla lonicera caprifoliaceae a species with underdeveloped linear embryos
Botany, 2000Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract: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 mos...
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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, 2000Co-Authors: Siti N Hidayati, Jeremy M Baskin, Charles C. BaskinAbstract: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.
Tomasz Pawlowski - One of the best experts on this subject based on the ideXlab platform.
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proteome analysis of norway maple acer platanoides l seeds Dormancy Breaking and germination influence of abscisic and gibberellic acids
BMC Plant Biology, 2009Co-Authors: Tomasz PawlowskiAbstract:Background Seed Dormancy is controlled by the physiological or structural properties of a seed and the external conditions. It is induced as part of the genetic program of seed development and maturation. Seeds with deep physiological embryo Dormancy can be stimulated to germinate by a variety of treatments including cold stratification. Hormonal imbalance between germination inhibitors (e.g. abscisic acid) and growth promoters (e.g. gibberellins) is the main cause of seed Dormancy Breaking. Differences in the status of hormones would affect expression of genes required for germination. Proteomics offers the opportunity to examine simultaneous changes and to classify temporal patterns of protein accumulation occurring during seed Dormancy Breaking and germination. Analysis of the functions of the identified proteins and the related metabolic pathways, in conjunction with the plant hormones implicated in seed Dormancy Breaking, would expand our knowledge about this process.
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proteomics of european beech fagus sylvatica l seed Dormancy Breaking influence of abscisic and gibberellic acids
Proteomics, 2007Co-Authors: Tomasz PawlowskiAbstract:A proteomic approach was used to analyze mechanisms of Dormancy Breaking in beech (Fagus sylvatica L.) seeds and the participation of abscisic and gibberellic acids (ABA and GA) in this process. After imbibition in water, ABA, or GA 3 solutions, beechnuts were subjected to cold stratification, which breaks their Dormancy. ABA delayed, whereas GA 3 promoted seed Dormancy Breaking. Proteome maps for water, ABA, and GA 3 were established, which displayed 1544 silver-stained spots. A total of 74 spots, showing significant changes in volume, were identified by MS. Of these, 18, 45, and 16 spots were identified as water-, ABA-, and GA 3 -responsive, respectively (five were regulated by both hormones). The classification of proteins showed that most of the proteins associated with Dormancy Breaking in water are involved in energy metabolism and protein destination. Most of the ABA-responsive proteins are involved in protein destination, energy metabolism, and development. Most of the GA 3 -responsive proteins are involved in energy metabolism (many more than for ABA and water) and plant defense. We conclude that the mechanism of seed Dormancy Breaking involves the proteins of many processes, beginning with hormone signal initiation, through signal transduction, transcription, protein synthesis, energy metabolism, storage materials, and ending with the cell cycle.