bluuebunny/crossref_metadata_2025_split huggingface dataset:
A comparative study of the seed germination biology of a narrow endemic and two geographically-widespread species ofSolidago(Asteraceae). 5. Effect of dry storage on after-ripening and survivorship
Authors: Walck Jeffrey L. , Baskin Jerry M. , Baskin Carol C. 
Published: September 2008

AbstractThe effect of dry storage under ambient laboratory conditions on after-ripening and survivorship was tested on seeds of the geographically-widespreadSolidago altissimaand S.nemoralisand the narrow-endemicS. shortii. Freshly-matured seeds ofS. altissimacollected in 1991 and in 1992 germinated to low or moderate percentages in light at 15/6, 20/10 and 25/15°C and to high percentages at 30/15 and 35/20°C, whereas those ofS. nemoralisandS. shortiigerminated to low percentages over the range of temperature regimes. After 0.8–1.8 years of storage, 1991 seeds ofS. altissimaincubated in light germinated to high percentages at 25/15, 30/15 and 35/20°C, those ofS. nemoralisdid so at 30/15 and 35/20°C and those ofS. shortiiat 20/10, 25/15, 30/15 and 35/20°C; 1992 seeds of all three species germinated to high percentages at 20/10, 25/15, 30/15 and 35/20°C. Freshly-matured 1991 and 1992 seeds of the three species germinated to low percentages in darkness over the range of temperature regimes, and only seeds ofS. shortiigerminated to high percentages after 0.8–1.8 years of storage. Compared with cold stratification, dry storage was only moderately effective in breaking dormancy in these three species. The primary difference in after-ripening of seeds of the three species was that seeds of the narrow endemic germinated to higher percentages in darkness than those of its two geographically-widespread congeners. Survivorship curves for 1991 and 1992 seeds ofS. altissimaandS. nemoralisand for 1992 seeds ofS. shortiiwere of Deevey Type I; the survivorship curve for 1991 seeds ofS. shortiiwas closest to Type II. Longevity of 1991 seeds ofS. altissima, 1992 seeds ofS. nemoralisand 1991 and 1992 seeds ofS. shortiiwas <4.0 years, whereas that of 1991 seeds ofS. nemoraliswas <2.3 years; 5% of 1992 seeds ofS. altissimawere viable after 4.0 years.
The effect of maturity on the moisture relations of seed longevity in foxglove (Digitalis purpureaL.)
Authors: Hay F.R. , Probert R.J. , Smith R. D. 
Published: September 2008

AbstractControlled aging experiments were carried out in order to evaluate the changes in seed longevity occurring following the attainment of maximum seed dry weight in foxglove (Digitalis purpureaL.). Seeds harvested in three successive years were stored at ~5% moisture content (fresh weight basis) and 50°C. Seed longevity was greater the later the seeds were harvested. When the data were modelled using the predictive viability model of Ellis and Roberts, these increases were attributable to increases in both the theoretical initial viability (in probits) of the seed-lot,Ki, and in the standard deviation of the normal distribution of seed deaths in time,σ. Furthermore, there was a positive relationship betweenKiandσwhich was independent of the year of harvest (r= 0.9016, for 11 d.f.,P< 0.001). These results do not support the predictive model which relies on the assumption thatσwill not differ between seed lots of the same species stored under identical conditions. When seeds were stored at a range of moisture contents (between 5 and 10%) at 50°C, increases inσduring seed development were manifest as changes in the negative logarithmic relationship betweenσand moisture content; below an upper limit, the regressions for seed lots at different stages of maturity were significantly different (P< 0.05) but could be constrained to either a common intercept or to a common slope (P< 0.05). It is proposed that it was the inherent variation in individual seed lifespans which increased during seed development. These results raise important concerns regarding the use of predetermined ‘species constants’ to predict the longevity of seed lots during long-term storage in seed banks.
Loss and induction of conditional dormancy in seeds of Sitka spruce maintained moist at different temperatures
Authors: Jones Steve K. , Ellis Richard H. , Gosling Peter G. 
Published: September 2008

AbstractPretreatment of moist seeds at certain temperatures can reduce seed dormancy, but such observations represent the net effect of pretreatment. Seeds of Sitka spruce (Picea sitchensis[Bong.] Carr.) were raised to 30% moisture content and pretreated at five different temperatures between 5 and 30°C for up to 24 weeks (168 d). Subsequent ability to germinate at 10°C and viability were then determined in order to investigate the effects of pretreatment on seed dormancy and survival. There was a curvilinear, negative semi-logarithmic relationship between seed longevity and pretreatment temperature, such that Q10for loss in viability increased from 2.6 between 10 and 20°C to 2.8 between 20 and 30°C. Simple multiplicative models combining cumulative normal frequency distributions for each of loss in viability and loss in dormancy were able to describe the changes in ability to germinate at 10°C, after pretreatment at 5, 10 and 30°C. However, in order to quantify the changes in ability to germinate observed at 10°C after pretreatment at 15°C, it was necessary also to invoke a model of dormancy reimposition, while for the results at 20°C it was necessary to postulate both dormancy reimposition and the further loss of this reimposed dormancy. It is concluded that moist seeds of Sitka spruce held at 15 and 20°C cycle between the dormant and non-dormant condition.
Developmental pattern of biotinylated proteins during embryogenesis and maturation of soybean seed
Authors: França Neto José B. , Shatters Robert G. , West S. H. 
Published: September 2008

AbstractThe developmental pattern of biotinylated proteins (BP) during embryogenesis and maturation of soybean seed was characterized. Detection of these BP was compared with the development of desiccation tolerance in seeds. Three groups of BP were detected in soybean seeds using a biotin-streptavidin detection method: the first group consisted of a set of three bands with a mean apparent MW of 85 kDa (called BP85), detected in crude extracts of embryonic axes (EA) from non-dehydrated seeds (NDS) and from artificially slow-dehydrated seeds (DS); the second one, BP75, was a single protein with an apparent MW of 75 kDa and was expressed in cotyledons (COT) and EA tissues of NDS and DS; the third group with a mean apparent MW of 35 kDa (BP35), was expressed at high levels only in COT of NDS. BP35 concentration was highest in the early stages of seed development (21 days after flowering — DAF) and decreased as seeds developed, being almost imperceptible after 47 DAF. Conversely, only traces of BP75 and BP85 extracted from EA and COT were detected at early stages of seed development (21–33 DAF). Maximum levels of accumulation of these proteins were expressed at 42–47 DAF and remained constant until harvest maturity. Desiccation-tolerant stage of the seeds was initiated at 47 DAF, which coincided with the stage of maximum accumulation of BP75 and BP85 in the seeds, however, appearance of these proteins could be stimulated by desiccation of immature seeds that had not achieved desiccation tolerance. Therefore changes in biotinylated proteins are coincident with, but not sufficient for, the development of desiccation tolerance.
Changes in selected plant growth regulators during germination in sorghum
Authors: Dewar J. , Taylor J. R. N. , Berjak P. 
Published: September 2008

AbstractThe technique of radioimmunoassay following sample resolution by HPLC was used to assay the amounts of the cytokinins zeatin (Z), zeatin riboside (ZR) and isopentenyladenine (IPA), the combined amounts of gibberellins1+3(GA1+3), and the amounts of indole acetic acid (IAA) and abscisic acid (ABA) during germination in grains of sorghum. Concentrations of GA1+3were low throughout germination and did not appear to be related to the time of germination. In the mature, non-germinated grain, the concentration of each of the other plant growth regulators was much higher in the smaller component comprised of the embryonic axis and scutellum than in the much larger endosperm tissue. During the germination period studied (64 h), these concentrations declined, with a peak in the amount of the cytokinin IPA and a small peak in Z+ZR (24 h) in the embryo following the first visible signs of root protrusion and coincident with a large enhancement in amylase activity. The high concentration of ABA in the embryo tissue prior to germination was noteworthy. It is suggested that the interaction of ABA and the cytokinins IPA and Z+ZR may play a significant role in controlling sorghum germination.
Cryopreservation of seeds of four coffee species (Coffea arabica, C. costatifructa, C. racemosa and C. sessiliflora): importance of water content and cooling rate
Authors: Dussert Stéhane , Chabrillange Nathalie , Engelmann Florent , Anthony François , Louarn Jacques , Hamon Serge 
Published: September 2008

AbstractIn the range of water contents studied (0.1–0.4 g H2O g dw−1),Coffea arabicaseeds were less sensitive to desiccation thanC. costatifructa, C. racemosaandC. sessilifloraseeds. At 0.20 g H2O g dw−1, 53% ofC. arabicaseeds germinated after direct immersion in LN (rapid cooling, 200°C min−1), but none of them developed into normal seedlings. By contrast, inC. costatifructa, C. racemosaandC. sessiliflora, when seeds were dehydrated to the optimal water content (0.19, 0.28 and 0.31 g H2O g dw−1, respectively), the percentages of seeds which developed into normal seedlings after LN exposure were 26, 78 and 31% of the desiccation control, respectively. Normal seedlings could be recovered from cryopreservedC. arabicaseeds only if they were desiccated to 0.20 g H2O g dw−1and precooled slowly to −50°C prior to immersion in LN. Precooling seeds at 2°C min−1allowed 25% of seeds to develop into normal seedlings. The thawing rate had no effect on the survival of cryopreservedC. arabicaseeds. In all cryopreservation experiments, the total germination did not reflect the percentage of seeds which developed into normal seedlings. Examination of excised embryos indicated a partial explanation of this difference since only the shoot apex was destroyed in abnormal embryos, whereas the hypocotyl and radicle were normal.
The seed bank dynamics ofCornus controversaand their rote in regeneration
Authors: Masaki Takashi , Tanaka Hiroshi , Shibata Mitsue , Nakashizuka Tohru 
Published: September 2008

AbstractSeed-bank dynamics ofC. controversa, a common tree in Japanese temperate forests, were investigated at Ogawa Forest Reserve by direct measurement of seed input, soil seed density, and seedling output (germination of soil seeds), together with two field experiments on postdispersal seed mortality. Soil seed density varied from 4 to 233 m−2in the site near conspecific adults (<5 m horizontally from crown edge), and 0 to 18 m−2in far sites (≥5 m) during the 1988–92 period. Seed input occurred only in 1988 and 1990: 190–740 m−2at the sites near conspecific adults, and 4–20 m−2at the far sites. Seedling output was observed every year and accounted for 0–15% of the loss from the seed bank, occasionally 30–60%. Seeds buried at 5-cm depth suffered moderate mortality (c.0.2 year−1) by fungal pathogens. In contrast, seeds experimentally placed on the ground suffered higher mortality (0.5–1 year−1) through predation by ground mammals, probably wood mice. In the experiment, seeds whose mesocarp was removed survived much better. On the other hand, distance itself did not appear to affect post-dispersal mortality of seeds. Seeds in canopy gaps also tended to suffer higher mortality. Current spatial pattern and mode of seed dispersal should decrease the potential ability of the seed bank of this species to colonize safe sites. Rare and unpredictable events might increase the contribution of the seed-bank strategy to regeneration in this forest.
Germination-related proteins in wheat revealed by differences in seed vigour
Authors: Guy P. A. , Black M. 
Published: September 2008

AbstractArtificial aging of wheat grains (Triticum aestivumcv. Mercia) for 3 d resulted in the gradual loss of seed vigour without loss of viability, but the latter decreased rapidly over the next 24 h. Loss of vigour was expressed as a delay in germination i.e. an increasing ‘lag’ period with aging before the onset of radicle emergence, but the subsequent rate of seedling growth was not affected. There was an overall decrease in the incorporation of35S-methionine into protein in aged embryos, and associated with the aging-induced delay in the completion of germination (i.e. start of radicle emergence) there was a delay in the production of certain polypeptides. In embryos of both non-aged and aged seeds these polypeptides appeared just prior to radicle emergence but several of these were never synthesized in embryos from non-viable seeds. The synthesis of mRNA coding forin vitrotranslated polypeptides, or groups of polypeptides, was similarly delayed in lowvigour embryos. Furthermore, some polypeptides were identified which were induced by the accelerated aging treatment. It is concluded that a reduced level of protein and mRNA synthesis in the embryos of low-vigour seeds may result in the delay in the accumulation of specific of mRNAs and polypeptides which are needed for the normal completion of germination, i.e. radicle emergence.
Reimposition of conditional dormancy during air-dry storage of prechilled Sitka spruce seeds
Authors: Jones Steve K. , Gosling Peter G. , Ellis Richard H. 
Published: September 2008

AbstractPrechilling seeds of Sitka spruce (Picea sitchensis[Bong.] Carr.) at 4°C with 30% moisture content for 12–14 weeks (84–98 d) removed conditional dormancy (i.e. they were then able to germinate at 10°C). The non-dormant status was preserved after redrying to 6% moisture content. However, conditional dormancy was gradually reimposed during subsequent air-dry storage at 4°C and 6% seed moisture content in all five seed lots tested. Further investigations with one seed lot showed that reimposition was reversed by a second prechill treatment, but was reimposed again during subsequent air-dry storage. The trend of dormancy reimposition within seed lots over time was quantified by negative exponential relations between ability to germinate at 10°C and duration of air-dry storage. The progress of dormancy reimposition was influenced by seed storage moisture content and was most rapid at 4–10%. At higher moisture contents (15 and 20%) the rate of the reimposition of conditional dormancy was much reduced, while at moisture contents of 25 and 30% further loss in dormancy occurred. Thus it is clear that dormancy reimposition occurred during storage at low water potential rather than solely during desiccation from high to low water potential.
Germination and vigour loss of non-sprouted and sprouted wheat seeds during storage – testing the viability constants
Authors: Stahl M. , Steiner A. M. 
Published: September 2008

AbstractThe loss of percentage germination and vigour of non-sprouted and sprouted seeds of winter wheat was determined during storage for 80 days at 11 different combinations of moisture content and temperature. Before storage the initial percentage germination and vigour were reduced according to the level of sprouting. During storage the percentage germination and vigour decreased. The rate of germination loss increased with increasing seed moisture content and/or increasing temperature. The species-specific constants KE, CW, CH and CQ of the viability equation were not different for non-sprouted and sprouted seeds. Likewise, the relation between the percentage of normal and abnormal seedlings was independent of sprouting. The rate of vigour loss was also independent of the storage conditions and of sprouting.
Effects of dormancy-breaking chemicals on ABA levels in barley grain embryos
Authors: Wang Mei , van der Meulen René M. , Visser Karin , Van Schaik Henk-Peter , Van Duijn Bert , de Boer Albertus H. 
Published: September 2008

AbstractThe endogenous ABA contents of dormant and nondormant barley grains were determined following application of different compounds to break dormancy. The chemicals used for breaking of dormancy in intact dormant grains were weak and strong acids, alcohols, hydrogen peroxide, cyanide, nitrate, salicylic acid, gibberellic acid and fusicoccin. The dormancy-breaking compounds could be classified into two major groups: compounds that caused a decrease in endogenous ABA (class I) and compounds which did not affect endogenous ABA (class II). Class I compounds included gibberellic acid, ethanol, hydrogen peroxide, nitrate, salicylic acid; class II compounds were fusicoccin, acid (H2SO4), sodium azide, n-caproic acid. In addition, these dormancy-breaking compounds were able to stimulate the germination rate when applied to embryos isolated from dormant grains. The concentrations necessary for stimulation of germination of isolated embryos were much lower than the concentrations for breaking the dormancy of intact grains. After embryos were isolated from dormant grains and incubated in water, ABA was determined in both embryos and in the incubation media. The class I compounds stated above also reduced ABA content in the incubation medium of isolated embryos, while class II compounds had no effect on ABA content of the medium. External application of ABA could overcome the effect of dormancy-breaking compounds of class I but not of class II. The results suggest that in the presence of the agents belonging to class II, ABA responsiveness of isolated embryos from dormant grains is decreased, compared to nontreated embryos.
Seed enhancements
Authors: Taylor A. G. , Allen P. S. , Bennett M. A. , Bradford K. J. , Burris J. S. , Misra M. K. 
Published: September 2008

AbstractSeed enhancements may be defined as post-harvest treatments that improve germination or seedling growth, or facilitate the delivery of seeds and other materials required at the time of sowing. This definition includes three general areas of enhancements: pre-sowing hydration treatments (priming), coating technologies and seed conditioning. Pre-sowing hydration treatments include non-controlled water uptake systems (methods in which water is freely available and not restricted by the environment) and controlled systems (methods that regulate seed moisture content preventing the completion of germination). Three techniques are used for controlled water uptake: priming with solutions or with solid particulate systems or by controlled hydration with water. These priming techniques will be discussed in this paper with reference to methodology, protocol optimization, drying and storage. Coating technologies include pelleting and film coating, and coatings may serve as delivery systems. Seed conditioning equipment upgrades seed quality by physical criteria. Integration of these methods can be performed, and a system is described to upgrade seed quality inBrassicathat combines hydration, coating and conditioning. Upgrading is achieved by detecting sinapine leakage from nonviable seeds in a coating material surrounding the seeds. Seed-coat permeability directly influences leakage rate, and seeds of many species have a semipermeable layer. The semipermeable layer restricts solute diffusion through the seed coat, while water movement is not impeded. Opportunities for future seed enhancement research and development are highlighted.
Seed development in Phaseolus vulgaris L. cv. Seminole. 3. NMR imaging of embryos during ethylene-induced precocious germination
Authors: Fountain David W. , Forde Lucy C. , Smith Edwin E. , Owens Karen R. , Bailey Donald G. , Callaghan Paul T. 
Published: September 2008

AbstractEmbryos taken from late maturation phase seeds of Phaseolus vulgaris cv. Seminole prior to seed desiccation (35–45 DAA) can be induced to germinate in the absence of water by exogenous ethylene. NMR imaging of proton relaxation within the embryo shows changes in water status in putative (and not fully differentiated) vascular tissues of the hypocotyl within 3 h of ethylene administration. Difference imaging revealed that the change was progressive in the hypocotyl towards the radicle tip and was accompanied by changes in water status in the cotyledons. Water within plumular leaves was also affected. Increase in diameter of the hypocotyl–radicle axis (as estimated by pixel counts) was detectable from 3 h. Longitudinal radicle growth was detectable by NMR imaging at 18 h. Visible germination under the conditions used was apparent after 20 h. Changes in water status detected by this technique are an indication of changes in activity (concentration) or motion of water molecules or both. The data are consistent with a mode of action of ethylene in stimulating a redistribution of water within embryo structures from cotyledons to axis via the cotyledonary node and allowing the axis access to water sufficient to support germination. This supports the hypothesis that in vivo, quiescence at this developmental stage is induced and maintained by sequestration of water within the cotyledons.
Iron transport and storage within the seed coat and embryo of developing seeds of pea (Pisum sativumL.)
Authors: Marentes Eduardo , Grusak Michael A. 
Published: September 2008

AbstractTo understand the cellular processes related to iron transport and sequestration within the developing pea seed (Pisum sativum), total iron and ferritin iron were analysed in seed coat and embryo tissues of the iron-hyperaccumulating pea mutant, Sparkle [dgl, dgl], and its wild-type parent, cv. Sparkle. For plants grown hydroponically with 2 μM Fe, embryo Fe concentrations averaged 65 μg g−1dry weight in mature wild-type seeds and 163 μg g−1dry weight in maturedglseeds; iron concentrations were also higher indglseed coats. Extracted and electrophoretically separated seed proteins were probed with a polyclonal antibody raised against pea seed ferritin. In both genotypes, ferritin was detected in the embryo, but not in the seed coat. Ferritin iron accounted for 92% of the total iron in mature wild-type embryos, but only 42% of the total iron in maturedglembryos. Radiotracer studies using59Fe were used to characterize the movement of iron within the seed coat. Unequal distribution of59Fe in opposing sections taken from the two hemispheres of the seed coat demonstrated that iron was symplastically phloem unloaded. These results suggest that iron resides transiently within the nonvascular seed coat cells and that all cells at the inner surface of the seed coat may be involved in the release of iron to the embryo apoplast. However, the form of iron resident within the seed coat and/or taken up by the embryo is presently unknown.
Flavonoids in seeds and grains: physiological function, agronomic importance and the genetics of biosynthesis
Authors: Shirley Brenda Winkel 
Published: September 2008

AbstractFlavonoids are secondary metabolites that are present at high levels in most plant seeds and grains. These compounds appear to play vital roles in defence against pathogens and predators and contribute to physiological functions such as seed maturation and dormancy. At the same time, particular subclasses of flavonoids, such as the proanthocyanidins (condensed tannins), negatively impact the use of seeds and grains in animal feed and can add undesirable qualities to food products for human consumption. This article presents an overview of investigations into the physiological and agronomic aspects of seed and grain flavonoids as well as a review of molecular genetic studies, particularly in maize,Arabidopsisand soybean, where mutants deficient in flavonoid biosynthesis provide useful tools for stydying the metabolic machinery underlying the accumulation of these compounds in reproductive structures.