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1.
Claudio Stasolla Edward C. Yeung 《In vitro cellular & developmental biology. Plant》1999,35(4):316-319
Summary The effects of exogenous applications of ascorbic acid on white spruce somatic embryogenesis were examined. Increasing concentrations
of ascorbate (1 μM to 100 μM) in the germination medium enhanced somatic embryo conversion in a linear fashion. At the optimal ascorbate level (100 μM) the number of embryos able to undergo normal conversion, i.e., emergence of both root and shoot, increased from 34% (control)
to 58%. The effect of ascorbate had a more pronounced effect on shoot growth than on root emergence; and at 100 μM ascorbate, the percentage of embryos able to produce new leaf primordia increased from 47% (control) to 79%. Root emergence
increased slightly from 64% in the control embryos to 74% in the presence of ascorbic acid. The ascorbate-treated embryos
were characterized by an enlarged apical region, presumably due to a larger number of leaf primordia produced, and by dark
green leaves. When allowed to grow further, these embryos were able to develop into normal plantlets. 相似文献
2.
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
3.
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
4.
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
5.
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
6.
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
7.
Summary Immunofluorescence methods were developed for examining the distribution of microtubules in freshly isolated and cultured protoplasts and regenerated somatic embryos of white spruce (Picea glauca). Freshly isolated protoplasts consisted of both uniand multinucleate types. Uninucleate protoplasts established parallel cortical microtubules during cell wall formation and cell shaping, divided within 24 h and developed into somatic embryos in culture. Dividing cells were characterized by preprophase bands (PPBs) of microtubules, atypical spindle microtubules focused at the poles and a typical phragmoplast at telophase. Multinucleate protoplasts also established parallel arrays of cortical microtubules during cell wall formation. In addition their nuclei divided synchronously within 4 days, then cell walls formed between the daughter nuclei. Individual multinucleate protoplast-derived colonies subsequently gave rise to elongate suspensor cells thereby forming embryo-like structures by 7 days. 相似文献
8.
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
9.
Summary Embryogenic callus was initiated from radicles of mature embryos removed from imbibed seeds (24 h). Embryogenic and other
nonembryogenic types of callus proliferated on a modified half-strength Murashige-Skoog medium (MS) basal medium (BM) supplemented
withmyo-inositol, casein hydrolysate (CH), L-glutamine (gln) and growth regulators kinetin (KN), N6-benzyladenine (BAP) each (20×10−6
M), 2,4-dichlorophenoxyacetic acid (2,4-D) (50×10−6
M) Embryogenic callus bearing suspensor-like cells in a mucilaginous gel matrix was isolated and maintained by subculture every
10 to 12 days on BM with KN, BAP each (2×10−6
M) and 2,4-D (5×10−6
M). Somatic embryos developed spontaneously from the callus on this medium at 23±1° C. Closer examination revealed that numerous
polyembryonic clusters, comprised of elongated cells (suspensors) and small dense cells with large nuclei (somatic embryos),
occurred in the viscous gel. When this enriched embryonal-suspensor mass was subcultured to low 2,4-D (1×10−6
M), globular embryos developed by 40 to 60 days. Upon transfer to a liquid medium without growth regulators, the embryos elongated
and developed cotyledons and shoots with needles. Plantlet development was completed by 30 days in a basal medium without
CH, gln and growth regulators. The total culture time was 150 days. Approximately 40±10 embryos were formed from 500 mg of
initial callus. Somatic embryogenesis became aberrant if embryos remained attached to the callus mass and were not subcultured
within 10 to 12 days according to the described protocol. Somatic embryos were encapsulated in an alginate gel and stored
at 4° C for nearly two months without visible adverse effects on viability.
Editor's Statement This paper presents advances in the in vitro regeneration of a commercially useful plant species from stored
seeds. In addition, data is presented on short-term storage of the plantlets, and long-term proliferation of the embryonal
mass in vitro. 相似文献
10.
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
11.
M. M. H. Kristensen J. I. Find F. Floto J. D. MØller J. V. NØrgaard P. Krogstrup 《Protoplasma》1994,182(1-2):65-70
Summary The development of somatic embryos in an embryogenic suspension culture ofPicea sitchensis was followed every day for two weeks after thawing from liquid nitrogen (LN2). Only a few cells, primarily located at the periphery of the embryonic region of the embryos, survived cryopreservation in LN2. Surviving cells were classified into two groups: embryogenic cells (EC) and non-embryogenic cells (NEC), based on their morphology and embryogenic competence. The dense cytoplasmic EC underwent organized growth and differentiation with first divisions occurring after 24 h, and embryo formation 6–8 days after thawing from LN2. No evidence of asymmetrical divisions or free-nuclear stages was found during somatic embryo formation. NEC had less dense cytoplasm with numerous small vacuoles. One to five days after thawing the NEC became progressively more vacuolated and elongated. Histological examination revealed no mitotic activity in NEC, and six days after thawing NECs were seen as single cells or unorganized cell aggregates. Two weeks after thawing the appearance of the cryopreserved cultures was comparable to that of the untreated cultures.Abbreviations EC
embryogenic cells
- ECC
embryogenic cell clusters
- FDA
fluorescein diacetate
- GMA
glycol methacrylate
- LN2
liquid nitrogen (–196°C)
- NEC
non-embryogenic cells 相似文献
12.
D. D. Ellis H. Barczynska B. H. McCown N. Nelson 《Plant Cell, Tissue and Organ Culture》1991,27(3):281-287
Picea glauca (white spruce) zygotic embryos and one-week-old-seedling epicotyl explants were placed on either Woody Plant Medium (WPM) or half-strength Schenk & Hildebrandt (1/2S&H) medium supplemented with varying levels of benzyladenine (BA) (0.1, 1.0, 10, 50, 100 M), zeatin (10, 50, 100 M) or thidiazuron (TDZ) (0.01, 0.1 M). In addition to differences in the number of buds induced at three months on the two media, buds induced on WPM were visually more uniform, less vitrified and elongated faster. On 1/2S&H supplemented with BA, maximum bud induction from embryos occurred on 1.0 M BA with 0.01 M TDZ with higher BA concentrations inhibitory to bud induction. In contrast, on WPM there was little difference in the number of buds induced from embryos placed on 10, 50 and 100 M BA with or without TDZ. One-week-old-seedling epicotyl explants required higher BA levels on 1/2S&H, as bud induction at three months was greatest at 10 M BA. On WPM, as with the embryos, there were only minor differences in the number of buds induced from epicotyl explants on the various BA levels. Zeatin was more effective at inducing buds than BA with both media. From embryos, bud induction was greatest on 50 or 100 M zeatin without TDZ and 50 or 100 M zeatin with or without TDZ on 1/2S&H and WPM respectively. From epicotyl explants on 1/2S&H, there was little difference in the number of buds induced with the zeatin concentrations used, while with WPM, 50 and 100 M zeatin induced the greatest number of buds. Interestingly, with BA, the epicotyl explants needed a higher level than the embryos for maximal response, while with zeatin, the level was the same for both embryos and epicotyl explants. Long-term (six month) survival was higher on WPM than with 1/2S&H. Additionally, embryos had a higher percentage of genotypes surviving at six-months when compared with epicotyl explants. For overall survival and development of the buds, 50 M zeatin with 0.01 M TDZ was the best treatment tested.Abbreviations BA
benzyladenine, 1/2S&H-half-strength Schenk & Hildebrandt medium
- TDZ
thidiazuron
- WPM
woody plant medium 相似文献
13.
Danielle Julie Carrier Cheryl A. Bock James E. Cunningham David R. Cyr David I. Dunstan 《In vitro cellular & developmental biology. Plant》1997,33(3):236-239
Summary Interior spruce (Picea glauca engelmannii complex) somatic embryos grown on 48 μmol (±)-ABA per L over a period of 42 d without transfer underwent precocious germination
by 49 d. Those transferred at 28 d to fresh medium with 48 μmol (±)-ABA continued embryo development until harvested at 56
d; the transfer at 28 d resulted in an increase in embryo lipid content after 42 d. Somatic embryos grown under this condition
contained 181.4±41.2, 116.0±42.4, and 91.8±33.6 ng (+)-ABA per mg of lyophilized tissue at 42, 49, and 56 d, respectively.
By comparison, embryos grown without the transfer at 28 d had 86.8±25.4 ng (+)-ABA per mg of lyophilized tissue at 42 d, just
prior to precocious germination. After 3 weeks’ storage in a drying chamber under high humidity, the (+)-ABA content of 56-d-old
transferred embryos decreased to 15.4 ± 4.4 ng (+)-ABA per mg of lyophilized tissue. The increased lipid content resulting
from embryo transfer and the reduction in internal (+)-ABA content during storage are factors which will contribute to improved
conversion of somatic embryos to plantlets. 相似文献
14.
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
15.
Aquea F Poupin MJ Matus JT Gebauer M Medina C Arce-Johnson P 《Biotechnology letters》2008,30(10):1847-1852
Pinus radiata is one of the most important forestry species in the southern hemisphere. This work describes the regeneration of this plant via somatic embryogenesis from immature zygotic embryos. To improve this process, somatic embryogenic cell suspensions were established in liquid media for the generation of material for embryo maturation. Each developmental stage of these suspensions was characterized by microscopy and their growth phases quantified. An alginate-containing medium was used as an encapsulation method for the somatic embryos that were then germinated as artificial seeds in vitro. The protocols described in this work are both useful and reliable for industrial purposes. 相似文献
16.
Summary Calli were induced from leaf expiants of aDactylis glomerata L. (orchardgrass) genotype which has a high capacity for somatic embryogenesis. After 7 months culture on SH medium containing NaCl, a line was selected which was tolerant to 200 mM NaCl. When both selected and nonselected calli were maintained for 56 days on media containing 0 to 300 mM NaCl, the selected line showed significantly higher regeneration capacity than nonselected calli when placed on media containing more than 50 mM NaCl. Ultrastructural features of control somatic embryos not exposed to the salt were compared to those from nonselected and selected embryos cultured on 200 mM NaCl medium. In the presence of NaCl there were changes in the appearance of cell walls and mitochondria, accumulation of lipids and a higher degree of vacuolation in cells of nonselected embryos compared to control and selected embryos. 相似文献
17.
David I. Dunstan Terry D. Bethune 《In vitro cellular & developmental biology. Plant》1996,32(3):165-170
Summary The yield of morphologically normal Stage 3 somatic embryos of white spruce [Picea glauca (Moench) Voss], and subsequent germinability, was affected by culture age and use of solid and/or liquid culture growth conditions.
Of the conditions that were compared, best results were obtained with cultures up to 3 yr old that had been continuously grown
in liquid medium. Such material yielded up to 374 morphologically normal Stage 3 embryos per g f. wt. inoculum, when routinely
pretreated using a 1 wk 2,4-dichlorophenoxyacetic acid-free period before maturation. By comparison the continual use of solid
culture conditions resulted in lower yields (5/g f. wt. inoculum), and the use of solid medium in combination with liquid
medium showed a greater affect of age on the production of normal Stage 3 embryos (348/g f. wt at 1.5 yr down to 19/g f. wt.
at 3 yr) over the age range tested. In the absence of culture pretreatment, the oldest liquid cultures yielded only 44 normal
Stage 3 embryos/g f. wt. inoculum, and the comparable solid to liquid cultures yielded 1.3/g f. wt. inoculum. The number of
aberrant Stage 3 embryos in older cultures was reduced as a result of culture pretreatment; for example, in the oldest liquid
cultures these represented 83% of the Stage 3 embryo population without pretreatment and 45% with pretreatment. Normal Stage
3 somatic embryo yield and germination characteristics (radicle and epicotyl development) were informative in distinguishing
among the conditions studied. Germination characteristics were especially important when maturation responses were incapable
of distinguishing among age classes.
NRCC Contribution no. 38462. 相似文献
18.
Somatic embryogenesis and plant regeneration from suspension cultures of Picea glauca (White spruce) 总被引:2,自引:0,他引:2
Hakman, I. and von Arnold, S. 1988. Somatic embryogenesis and plant regeneration from suspension cultures of Picea glauca (White spruce). - Physiol. Plant. 72: 579–587.
Plantlets were regenerated from long-term embryogenic cultures of Picea glauca (Moench) Voss. (White spruce). Embryogenic calli, initiated from immature zygotic embryos and maintained by monthly subculture for 16 months, were used to establish suspension cultures. Small somatic embryos were continuously produced in liquid culture medium containing auxin and cytokinin and the cultures showed a sustained regeneration capacity for >6 months. Somatic embryos propagated in the suspension cultures developed further into embryos bearing cotyledons, about 1 month after transfer to solidified medium containing abscisic acid. Electron microscopic examination revealed that storage nutrients, lipids, proteins and carbohydrates, accumulated in the somatic embryos during this treatment with abscisic acid (ABA). Upon subculture to medium lacking plant growth regulators such embryos could develop into small green plantlets. 相似文献
Plantlets were regenerated from long-term embryogenic cultures of Picea glauca (Moench) Voss. (White spruce). Embryogenic calli, initiated from immature zygotic embryos and maintained by monthly subculture for 16 months, were used to establish suspension cultures. Small somatic embryos were continuously produced in liquid culture medium containing auxin and cytokinin and the cultures showed a sustained regeneration capacity for >6 months. Somatic embryos propagated in the suspension cultures developed further into embryos bearing cotyledons, about 1 month after transfer to solidified medium containing abscisic acid. Electron microscopic examination revealed that storage nutrients, lipids, proteins and carbohydrates, accumulated in the somatic embryos during this treatment with abscisic acid (ABA). Upon subculture to medium lacking plant growth regulators such embryos could develop into small green plantlets. 相似文献
19.
Helena I. Hjortswang Lada H. Filonova Tiina Vahala Sara von Arnold 《Plant Growth Regulation》2002,38(1):75-82
The differentiation of a surface layer on the embryonal mass is one ofthe first markers for normal embryo development in Norway spruce. We havepreviously shown that this differentiation is closely interlinked with a switchin the expression pattern of Pa18, a putative lipidtransfer protein (LTP) gene. In transgenic embryos ofNorway spruce under- or overexpressing the Pa18 gene under the maize ubiquitin promoter, there is no switch in the expression pattern ofthe Pa18 gene and the embryos are blocked in theirdevelopment early during maturation. In this work, we describe how under- andoverexpression of Pa18 affect sequential developmentalstages during somatic embryogenesis. The differentiation of somatic embryosfromproembryogenic masses is not affected, but the morphology of early somaticembryos is changed. Both under and overexpressing somatic embryos can gothrougha maturation process, although at a much lower frequency than the controlembryos. Germination is not affected by altered Pa18expression. However, plants regenerated from under and highly overexpressingsomatic embryos cannot survive prolonged culture. 相似文献
20.
A tonoplast intrinsic protein (TIP) is present in seeds, roots and somatic embryos of Norway spruce (Picea abies) 总被引:3,自引:0,他引:3
Many plant species contain a seed-specific tonoplast intrinsic protein (TIP) in their protein storage vacuoles (PSVs). Although the function of the protein is not known, its structure implies it to act as a transporter protein, possibly during storage nutrient accumulation/breakdown or during desiccation/imbibition of seeds. As mature somatic embryos of Picea abies (L.) Karst. (Norway spruce) contain PSVs, we examined the presence of TIP in them. Both the megagametophyte and seed embryo accumulate storage nutrients, but at different times and we therefore studied the temporal accumulation of TIP during seed development. Antiserum against the seed-specific a-TIP of Phaseolus vulgaris recognized an abundant 27 kDa tonoplast protein in mature seeds of P. abies. By immunogold labeling of sectioned mature megagametophytes we localized the protein to the PSV membrane. We also isolated the membranes of the PSVs from mature seeds and purified an integral membrane protein that reacted heavily with the antiserum. A sequence of 11 amino acid residues [AEEATHPDSIR], that was obtained from a polypeptide after in-gel trypsin digestion of the purified membrane protein, showed high local identity to a-TIP of Arabidopsis thaliana and to a-TIP of P. vulgaris. The greatest accumulation of TIP in the megagametophytes occurred at the time of storage protein accumulation. A lower molecular mass band also stained from about the time of fertilization until early embryo development. The staining of this band disappeared as the higher molecular mass (27 kDa) band accumulated in the megagametophyte during seed development. Total protein was also extracted from developing zygotic embryos and from somatic embryos. In zygotic embryos low-levels of TIP were seen at all stages investigated, but stained most at the time of storage protein accumulation. The protein was also present in mature somatic embryos but not in proliferating embryogenic tissues in culture. In addition to the seed tissue material, the antiserum also reacted with proteins present in extracts from roots and hypocotyls but not cotyledons from 13-day-old seedlings. 相似文献