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1.
David I. Dunstan Stephanie Berry Cheryl A. Bock 《In vitro cellular & developmental biology. Plant》1994,30(3):156-159
Summary We investigated abscisic acid (ABA) metabolism among Norway and white spruce somatic embryo cultures which exhibited differences
in maturation response when placed on racemic abscisic acid [(±)-ABA]. Differences in metabolic rate among the spruce genotypes
could affect the ABA pool available for the maturation process, and might therefore be responsible for the differences in
maturation response. The production of cotyledonary (stage 3) somatic embryos in cultures (genotypes) of Norway spruce (PA86:26A
and PA88:25B) and of white spruce (WS1F cryoD and WS46) was compared. In each species pair one of the two genotypes failed
to show stage 3 embryo development (respectively, PA88:25B and WS46). The investigation of ABA metabolism of each species
pair showed that no substantial differences in ABA consumption or in the production of metabolites occurred. In each case
ABA was metabolized to phaseic acid and dihydrophaseic acid over the 42-day culture period, metabolites were recoverable from
the agar-solidified medium, and the sum of residual ABA and metabolites were equivalent to the ABA initially supplied. The
results indicate that the process of ABA metabolism occurs essentially independently of somatic embryo maturation.
NRCC no. 37345. 相似文献
2.
The effects of glutamine-based dipeptides, glutamine and casein hydrolysate, as well as the deletion of organic nitrogen, were investigated during white spruce [Picea glauca (Moench) Voss] somatic embryogenesis. There were no differences in the fresh weight increase of the tissue masses grown on initiation medium with different combinations of organic nitrogen. This was also the case for subsequent growth on kinetin medium, except that glutamine alone produced a significantly lower fresh weight increase than the other organic nitrogen combinations. Without organic (i.e. with only inorganic) nitrogen in the medium, the fresh weight increase was significantly less than with organic nitrogen on both initiation and kinetin medium. No differences were found between the dry/fresh weight ratios obtained with the various nitrogen treatments. The number of mature embryos produced per gram fresh weight when cultured in the absence of organic nitrogen was significantly higher than that obtained in its presence. There were no differences in the total number of mature embryos produced in cultures grown with various organic nitrogen combinations or without organic nitrogen. There were large clone differences with respect to the number of mature somatic embryos per gram tissue and the total number of somatic embryos produced. Hence, nitrogen type influences culture growth rate but not the number of mature somatic embryos produced. The latter was clone dependent.Abbreviations
BA
6-benzylaminopurine
-
CH
casein hydrolysate 相似文献
3.
The haploid megagametophyte of white spruce (Picea glauca) seeds undergoes programmed cell death (PCD) during post-germinative seedling growth. Death of the megagametophyte storage parenchyma cells was preceded by reserve mobilization and vacuolation. TUNEL (terminal deoxynucleotidyltransferase-mediated dUTP nick-end labeling)-positive nuclei indicated that the first megagametophyte cells to die were those closest to the radicle at the micropylar end of the seed as well as those that comprised the most peripheral and innermost layers at the chalazal end of the seed. The death process was accompanied by nuclear fragmentation and internucleosomal DNA cleavage and the sequential activation of several nucleases. The latter comprised at least two groups: those induced relatively early during post-germinative seedling growth, that had pH optima in the neutral range (33, 31, 17 and 15 kDa), and those induced later that had pH optima in the acidic range (73, 62, 48, 43 and 29 kDa). Activities of all of the nucleases were stimulated by Ca2+, Mg2+ and Mn2+; only the nucleases active at neutral pH were inhibited by Zn2+. The temporal pattern of induction of the neutral and acidic nucleases may suggest that the latter function after tonoplast rupture. 相似文献
4.
Summary This report describes a low-cost method for generating large numbers of high quality mature white spruce (Picea glauca [Moench.] Voss) somatic embryos which survived desiccation and grew to plantlets more vigorously than excised zygotic embryos cultured in vitro. Somatic embryos from suspension culture were supported within a culture chamber on a flat absorbent pad above the surface of a liquid culture medium containing 20–50 M abscisic acid and 7.5 % polyethylene glycol. Throughout a 7 week culture period 3 L of fresh medium was pumped into one end of the chamber, while the spent medium exited by gravity from the opposite end. Over 6,300 cotyledonary stage white spruce somatic embryos were recovered after this time from a single culture chamber without manual manipulation. The somatic embryos were of excellent appearance with well developed cotyledons, and possessed high levels of storage lipids. They survived drying to about 8 % moisture content following treatment for 4 weeks at 63 % relative humidity, and following imbibition converted to normal plantlets at a frequency of 92 %, compared to 80 % for embryos grown in Petri dishes. Somatic embryos cultured within the bioreactor developed to plantlets that were 20 % longer than zygotic embryos excised from mature seed and grown in vitro, and were 38 % longer than somatic embryos cultured upon agar medium in Petri dishes.Plant Research Centre contribution No. 1523 相似文献
5.
6.
Summary Four scanning electron microscope techniques for preparing somatic and zygotic embryos of white spruce (Picea glauca [Moench] Voss.) were compared. Direct sputter coating without critical point drying worked well for desiccated embryos while conventional methods using chemical fixation were appropriate for hydrated somatic embryos. Low temperature scanning electron microscopy and plastic replicas provided excellent specimens of all embryos studied. Plastic replicas were used to document cotyledon formation and growth during maturation of somatic embryos. Apart from some differences in embryo size, orientation of cotyledons and surface wrinkling, the general morphology of mature somatic embryos of white spruce was very similar to zygotic embyros at a similar stage of development. 相似文献
7.
M. A. K. Khalil 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1985,69(3):247-251
Summary The paper presents results of a growth chamber progeny test of selected phenotypically superior trees from two white spruce (Picea glauca (Moench.) Voss.) populations in central Newfoundland, Canada. On the basis of heritability of 11 juvenile characters the superior trees have been demonstrated to be suitable as a base population for continued advanced generation breeding. Family selection would produce good genetic gains in the first generation but these can be enhanced considerably by selection of best individuals within the best families for clonal propagation in the second generation or propagation by seed in the second and subsequent generations. 相似文献
8.
Applications of DL-buthionine-[S,R]-sulfoximine deplete cellular glutathione and improve white spruce (Picea glauca) somatic embryo development 总被引:1,自引:0,他引:1
In white spruce (Picea glauca), an improvement of somatic embryo yield and quality can be achieved by applications of dl-buthionine-[S,R]-sulfoximine (BSO), which inhibits the biosynthesis of reduced glutathione (GSH), thereby switching the total glutathione
pool towards its oxidized form (GSSG). Applications of BSO almost tripled the embryogenic output of two cell lines by increasing
the number of embryos produced by 100 mg−1 tissue from 65 to 154 in the (E)WS1 line and from 59 to 130 in the (E)WS2 line. This increase in embryo number was ascribed
to a higher production of morphologically normal embryos with four or more cotyledons (group A embryos), at the expense of
group B embryos, characterized by fewer cotyledons. The quality of the embryos produced, estimated by their post-embryonic
performance, was also different between treatments. In both cell lines applications of BSO in the maturation medium increased
the conversion frequency, i.e. root and shoot emergence, of group A embryos while it enhanced root emergence in group B embryos.
Compared to their control counterparts, BSO-treated embryos had normal shoot apical meristems as in their zygotic counterparts.
Such meristems were characterized by large apical cells and vacuolated sub-apical cells. They also lacked intercellular spaces,
which were present in the apical poles of control embryos where they contributed to cell–cell separation and meristem degradation.
Furthermore, storage product accumulation was also improved in the presence of BSO, with protein bodies prevailing over starch.
These data show that an oxidized glutathione environment is beneficial for spruce embryo production in vitro. 相似文献
9.
Structure of the intergenic spacer region from the ribosomal RNA gene family of white spruce (Picea glauca) 总被引:2,自引:0,他引:2
Five genomic clones containing ribosomal DNA repeats from the gymnosperm white spruce (Picea glauca) have been isolated and characterized by restriction enzyme analysis. No nucleotide variation or length variation was detected within the region encoding the ribosomal RNAs. Four clones which contained the intergenic spacer (IGS) region from different rDNA repeats were further characterized to reveal the sub-repeat structure within the IGS. The sub-repeats were unusually long, ranging from 540 to 990 bp but in all other respects the structure of the IGS was very similar to the organization of the IGS from wheat, Drosophila and Xenopus. 相似文献
10.
David R. Cyr Wayne R. Lazaroff Susanna M. A. Grimes Grant Quan Terry D. Bethune David I. Dunstan Dane R. Roberts 《Plant cell reports》1994,13(10):574-577
Summary Embryogenic cultures of interior spruce derived from 12 full-sib families were subjected to cryopreservation, with a 97 % success rate for 357 genotypes. Analyses suggested that cryotolerance was not related to family ranking (height increment), embryogenic potential or culture dispersability in suspension, and long-term storage in or above liquid nitrogen did not affect regenerative potential. By contrast, differences in cryotolerance among cell lines appeared to be prevalent in certain families. Analysis with a DNA fingerprinting probe used for clonal identification demonstrated no evidence of somaclonal variation as a result of cryopreservation. The results of this work indicate the applicability of cryopreservation as a long-term storage strategy for spruce embryogenic cultures from a wide genetic background.Abbreviations ABA
± abscisic acid
- BA
N6-benzyladenine
- BSA
bovine serum albumin
- CTAB
cetyldimethylethyl-ammonium bromide
- DMSO
dimethylsulfoxide
- DTT
dithiothreitol
- EDTA
ethylenediaminetetraacetic acid disodium salt
- IBA
indole-3-butyric acid
- LN
liquid nitrogen
- PEG
polyethylene glycol
- SLS
N-lauroyl sarcosine
- Tris
tris[hydroxymethylamino] methane
- 2,4-D
2,4-dichlorophenoxyacetic acid 相似文献
11.
Summary Somatic embryos in embryogenic callus cultures derived from Immature zygotic embryos ofPicea glauca (White spruce) were examined by light and electron microscopy. Somatic embryos consist of an embryonic region of small densely cytoplasmic cells subtended by a suspensor consisting of long highly vacuolated cells. Mitotic figures are frequent in the embryonic cells but are not observed in the suspensor. Cell divisions in the embryonic region apparently produce rows of cells which elongate to form the suspensor. The presence of abundant polysomes, coated membranes and dictyosomes in the cytoplasm of embryonic and upper suspensor cells suggests rapid growth of the embryo. In contrast the basipetal suspensor cells appear to be senescing. While only a few scattered microfilaments are present in the meristematic cells, the upper suspensor cells contain numerous bundles of longitudinally oriented microfilaments. These bundles correspond to actin cables observed in light microscope preparations stained with rhodamine labelled phalloidin and are oriented parallel to the direction of active streaming in these cells. 相似文献
12.
For many years a widespread disorder has occured with Picea pungens glauca in nurseries near Hamburg, with chlorotic and sometimes necrotic needles at the tip of current shoots. From a survey investigation, a pot trial and a field trial it was concluded that K deficiency was the cause of the disorder, and that it was probably aggravated by oversupply of N. 相似文献
13.
Somaclonal variation in cryopreserved embryogenic clones of white spruce [Picea glauca (Moench) Voss.] 总被引:2,自引:0,他引:2
L. L. DeVerno Y. S. Park J. M. Bonga J. D. Barrett C. Simpson 《Plant cell reports》1999,18(11):948-953
Trees were regenerated from six white spruce embryogenic clones after cryopreservation for 3 and 4 years, respectively. Genetic
stability was evaluated using randomly amplified polymorphic DNA (RAPD) fingerprints. Somaclonal variation was detected in
some in vitro embryogenic cultures 2 and 12 months after they were re-established following cryopreservation but not in the corresponding
regenerated trees. These results suggest that trees regenerated from cryopreserved cultures in subsequent years are primarily
genetically stable in the genomic regions tested and that variation observed due to the in vitro culture process infrequently affects trees regenerated from normally maturing and germinating somatic embryos. However, trees
regenerated from somatic embryos that matured or germinated abnormally in in vitro culture exhibited altered RAPD fragment patterns.
Received: 20 July 1998 / Revision received: 15 October 1998 / Accepted: 14 December 1998 相似文献
14.
Embryogenic tissues of white spruce [Picea glauca (Moench) Voss] remain in an early developmental stage while cultured on 2,4-dichlorophenoxyacetic acid and N6-benzyladenine, but develop to cotyledonary embryos when these phytohormones are replaced by abscisic acid. Twenty-eight cDNAs were isolated from cotyledonary embryos by differential screening against immature embryo and non-embryonic tissues. Temporal expression patterns of these cDNAs during ABA-stimulated somatic embryo development were observed. This showed that clones could be allocated to various groups, including embryo-abundant, embryo-maturation-induced, and those whose expression was modulated during embryo development, germination or in non-embryogenic tissues. Expression corresponding to these cDNA clones showed that there were various responses to exogenous ABA or polyethylene glycol during a period of 48 h. Analyses of DNA and predicted amino acid sequence revealed that 12 of 28 cDNA clones had no known homologues, while others were predicted to encode different late-embryogenesis-abundant proteins, early methionine-labelled proteins, storage proteins, heat-shock proteins, glycine-rich cell wall protein, metallothionein-like protein and some other metabolic enzymes.Abbreviations 2,4-D
2,4-dichlorophenoxyacetic acid
- ABA
abscisic acid
- BA
N6-benzyladenine
- cDNA
complementary deoxyribonucleic acid
- Em
early methionine-labelled
- HSP
heat-shock protein
- LEA
late embryogenesis abundant
- PEG
polyethylene glycol
The authors thank Mr. Terry Bethune for his assistance, and Dr. Larry Pelcher, Mr. Barry Panchuk and Mr. Don Schwab for DNA sequencing and primer synthesis. This is National Research Council of Canada publication number 38929. 相似文献
15.
Summary Mesophyll protoplasts isolated fromPetunia hybrida were subjected to UV radiation (280–360 nm) in an attempt to assess whether (a) UV radiation has an effect on cortical microtubule organization, (b) UV radiation affects the progression of protoplasts through the cell cycle, and (c) there is a connection between the effect of UV radiation on cell division and the polymerization state of the microtubules. The proto plasts were irradiated with the following UV doses: 4, 8, 12, and 24mmol photons/m2, 30 min after isolation. Cell cycle analysis and immuno-localization of microtubules were carried out 0, 24, 48, and 72 h after irradiation. The length of cortical microtubules was determined after irradiation and in corresponding controls. We found that UV radiation induced breaks in cortical microtubules resulting in shorter fragments with increasing dose. Also, the protoplasts were delayed in their progression through the cell cycle, with G1 and G2 phases being affected as well as the S phase. The commencement of DNA synthesis in the irradiated protoplasts followed the re-establishment of a microtubule network. At 48 h after irradiation the protoplasts in all treatments, except for the 24 mmol/m2, had cortical microtubules of similar length, and at 72 h after irradiation only the protoplasts that had received 24 mmol photons/m2 had not started dividing.Abbreviations BSA
bovine serum albumin
- DMSO
dimethyl sulfoxide
- FDA
fluorescein diacetate
- MT
microtubules
- MTSB
microtubule stabilizing buffer
- PAR
photosynthetically active radiation (400–700 nm)
- PBS
phosphate buffered saline
- UV
ultraviolet 相似文献
16.
17.
18.
Daryl A. Reid John N. A. Lott Stephen M. Attree Larry C. Fowke 《In vitro cellular & developmental biology. Plant》1999,35(4):303-308
Summary Potassium leakage and morphological changes during imbibition of white spruce [Picea glauca (Moench) Voss] seeds and somatic embryos were investigated. A single desiccated somatic embryo, a single somatic embryo exposed
to a high relative humidity environment for 2 d, and a single dry zygotic embryo leaked similar amounts of potassium over
a 120-min period of imbibition in liquid germination medium. A seed without a seed coat leaked two and eight times more potassium
than a single whole seed and a single zygotic embryo, respectively. Nearly 50% of the potassium leaked for all tissues was
leaked within the first 20 min of imbibition. Exposure of somatic embryos to an environment with high relative humidity resulted
in a reduction in the percentage of potassium leaked after 80 and min to levels equivalent to those for zygotic embryos. Using
an environmental scanning electron microscope, we found that desiccated somatic embryos and dry zygotic embryos had wrinkled
surface cells, with cells in the surface of zygotic embryos being more shrunken in appearance. Imbibition of both types of
embryos in water resulted in turgid surface cells after 2 h. Imbibition in liquid germination medium did not cause much hydration
of surface cells, which still had wrinkled appearances after 2 h. Finally, imbibition on filter paper on semisolidified germination
medium resulted in slower hydration of somatic and zygotic embryos. Cells near the medium appeared hydrated while cotyledon
surface cells furthest from the medium resembled cells in desiccated embryos. 相似文献
19.
Development of microsatellite markers for white spruce (Picea glauca) and related species 总被引:9,自引:0,他引:9
R. B. Hodgetts M. A. Aleksiuk A. Brown C. Clarke E. Macdonald S. Nadeem D. Khasa E. Macdonald 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2001,102(8):1252-1258
We report the development of 13 primer pairs that allow the unambiguous amplification of 15 microsatellite (SSR) loci in white
spruce (Picea glauca). Fourteen of these loci were polymorphic in trees sampled at three geographically separated regions of western Canada. Segregation
analysis carried out on these loci confirmed a Mendelian inheritance pattern for all except two, which showed significant
segregation distortion. All of these primer pairs amplified SSR loci in at least one of the other Picea species tested [black spruce (P. mariana), red spruce (P. rubens), Norway spruce (P. abies), Colorado spruce (P. pungens), sitka spruce (P. sitchensis) and Engelmann spruce (P. engelmannii)]. Given the important commercial and ecological roles of these species, this set of markers will be invaluable for their
management, the improvement of commercially important traits, and the study of their ecology and genetics.
Received: 18 August 2000 / Accepted: 28 September 2000 相似文献
20.
Summary Embryogenic cell lines of Picea abies are categorized into three groups (polar, solar, and undeveloped) based on the organization of the somatic embryos within the tissue and the ability of the somatic embryos to proceed through a maturation process when treated with ABA. The polar and the solar types consist of somatic embryos with densely packed embryonic regions subtended by vacuolated suspensors. Both types of tissue regenerate mature somatic embryos when treated with ABA. Almost all mature somatic embryos develop further into shoots or plantlets. The undeveloped type consists of somatic embryos comprised of only a few loosely aggregated cells in their embryonic regions. Mature somatic embryos were not observed with this tissue type.Abbreviations ABA
cis-trans abscisic acid
- A1
polar type
- A2
solar type
- B
undeveloped type
- BA
benzyladenine
- 2,4-D
2,4 di-chlorophenoxyacetic acid
- LP
von Arnolds medium (1987) 相似文献