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1.
Waxflowers (Chamelaucium spp.) are native to Australia and now are grown for the cut flower industry worldwide. As part of an effort to achieve somatic
hybridization between the species to improve flower quality, somatic embryogenesis was achieved for Chamelaucium uncinatum and C. repens. Somatic embryos from young leaves of C. uncinatum and C. repens were induced in vitro on Murashige and Skoog (MS) agar medium containing 20 g/l sucrose and 2,4-dichlorophenoxyacetic acid
(2,4-D). For C. uncinatum, up to 4% of explants developed somatic embryos at 20 μM 2,4-D and for C. repens, up to 3% developed somatic embryos at 5 μM 2,4-D. Somatic embryos of C. uncinatum were also induced from immature seeds—a maximum of 6% of seed explants producing somatic embryos on MS medium containing
0.05 μM 6-benzyladenine (BA) and 0.5 μM Naphthalene acetic acid (NAA). Somatic embryo cultures maintained on MS medium supplemented
with 0.1 μM 2,4-D were induced to develop into plantlets after transfer to a hormone-free medium under light. 相似文献
2.
T. H. Lan P. I. Hong C. C. Huang W. C. Chang C. S. Lin 《In vitro cellular & developmental biology. Plant》2009,45(1):44-47
Whole plants were regenerated from excised leaves of Drimiopsis kirkii Baker (Lily of the Valley) through direct somatic embryogenesis. An initial exposure to a low level of 2,4-dichlorophenoxyacetic
acid (2,4-D, 0.45 μM) in the medium was essential in inducing the direct formation of somatic embryos. A high concentration
of 2,4-D (4.52 μM) in the proliferation medium reduced embryogenesis and enhanced callus formation. The presence of kinetin
in the medium enhanced the somatic-embryogenesis-inducing effect of 2,4-D (0.45 μM). The maximum embryogenesis rate (4,026
somatic embryos per gram of leaf) was obtained in explants cultured for 30 d in medium supplemented with 2.33 μM kinetin and
0.45 μM 2,4-D (embryo induction medium). Kinetin (4.65 μM) also enhanced embryo germination (97.6%), but the presence of α-naphthalene
acetic acid in the medium drastically reduced embryo germination. Following conversion, the regenerated plantlets were transferred
to soil and showed normal morphological characteristics. 相似文献
3.
Xiaoling Li Xiaoming Yu Ningning Wang Qizhi Feng Zhenying Dong Lixia Liu Jinglin Shen Bao Liu 《Plant Cell, Tissue and Organ Culture》2007,90(2):153-168
A simple tissue culture protocol was developed for efficient plant regeneration from young inflorescence-derived calli in
wild barley, Hordeum brevisubulatum (Trin.) Link, an important pasturage grass. Genetic and epigenetic instabilities in the regenerated plants (regenerants)
were assessed by three molecular markers AFLP, S-SAP and MSAP. Two pools of calli derived from young inflorescences of a single
donor plant and 44 randomly chosen regenerants were subjected to AFLP analysis. Results showed that 74 out of 793 scored bands
were polymorphic among the studied samples, giving rise to a genetic variation frequency of 9.3%. The number of variant bands
as compared to the donor plant varied greatly among the regenerants, with a small number of regenerants accumulated a large
number of variant bands (maximum 55), while the majority of regenerants showed only 2–3 variant bands. A subset of regenerants
together with the two pools of calli were selected for S-SAP and MSAP analysis to detect possible retrotranspositional activity
of a prominent retroelement family, BARE-1, in the genomes of Hordem species, and possible alterations in cytosine methylation. S-SAP analysis showed that of the 768 scored bands, 151 were polymorphic
among the analyzed samples, giving rise to a genetic variation frequency of 19.7%, albeit no evidence for retrotranspositional
event was obtained based on locus-specific PCR amplifications. MSAP analysis revealed that tissue culture has caused cytosine
methylation alterations in both level and pattern compared with the donor plant. Sequencing of selected variant bands indicated
that both protein-coding genes and transposon/retrotransposons were underlying the genetic and epigenetic variations. Correlation
analysis of the genetic and epigenetic instabilities indicated that there existed a significant correlation between MSAP and
S-SAP (r = 0.8118, 1,000 permutations, P < 0.05), whereas the correlation between MSAP and AFLP (r = 0.1048) is not statistically significant.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Xiaoling Li and Xiaoming Yu contributed equally to this work. 相似文献
4.
Janhvi Mishra Mahendra Singh L. M. S. Palni S. K. Nandi 《Plant Cell, Tissue and Organ Culture》2011,104(2):181-186
In vitro grown microshoots of Picrrhiza kurrooa were encapsulated in the alginate beads. Regrowth of encapsulated microshoots, using alginate encapsulation, of P. kurrooa reached 89.33% following 3 months of storage. Amongst developing plantlets, 42.66% exhibited formation of multiple shoots
at the onset of regrowth and 21.43% demonstrated simultaneous formation of shoots and roots. Healthy root formation was observed
in plantlets following 2 weeks of their transfer to half-strength Murashige and Skoog medium containing 1 μM α-naphthalene
acetic acid. Plants were transplanted to the greenhouse in three batches with 95% frequency of survival. The genetic fidelity
of P. kurrooa plants growing out after storage in encapsulated form was ascertained by random amplified polymorphic DNA (RAPD) analysis.
Molecular analysis of randomly selected plants from each batch was conducted using 45 random decamer primers. Of 45 primes
tested, 14 produced scorable amplified products. Total 68 bands were observed amongst them 7.35% bands were polymorphic. Cluster
analysis of the RAPD profile revealed an average similarity coefficient of 0.966 thus confirming genetic stability of plants
derived from encapsulated microshoots following 3 months of storage. 相似文献
5.
Douglas A. Steinmacher Charles R. Clement Miguel P. Guerra 《Plant Cell, Tissue and Organ Culture》2007,89(1):15-22
Various factors affect the induction of somatic embryogenesis in peach palm (Bactris gasipaes Kunth). Among these, both the type and level of auxins had the greatest influence on in vitro responses, although the genotype
and the developmental stage of the explants also influenced results. Younger inflorescences were more competent to respond
to SE induction than more mature inflorescences and the use of a pre-treatment with 2,4-D (200 μM) in liquid MS culture medium
also increased the embryogenic capacity, and diminished the development of flower buds. Higher oxidation rates were observed
in explants maintained on 2,4-D-supplemented culture medium, while on 300 μM or 600 μM Picloram and Dicamba lower oxidation
rates were observed. The progression from floral meristem to flower bud occurred at high frequency when low concentrations
of auxins were used, independent of the type. Higher concentrations of Picloram or Dicamba reduced or even inhibited flower
bud development. Picloram also enhanced the embryogenic induction rate more than 2,4-D and Dicamba, and among the concentrations
evaluated 300 μM Picloram enhanced induction for both genotypes, with significant differences between genotypes. The best
combination of variables used the least mature inflorescence (Infl1) from genotype I with the 2,4-D pre-treatment and 300 μM Picloram to generate 5 embryogenic calli from 18 explants; 26 embryos
were obtained on average from each embryogenic callus. From these, eighteen embryos converted to plantlets and six of these
survived transfer to the greenhouse. 相似文献
6.
Suchitra Banerjee Flora Haider G. D. Bagchi A. Samad 《Plant Cell, Tissue and Organ Culture》2010,103(2):189-196
We have used apical meristem culture to develop an efficient protocol for reducing phytoplasma infection of Artemisia roxburghiana Besser var. purpurascens (Jacq.) Hook. plants. Shoot tips of different sizes from phytoplasma-infected field-grown plants were treated with 0.1% mercuric
chloride (HgCl2) for 1 min followed by a 30-s exposure to 70% ethanol. The size of the explants significantly influenced the survival frequency
and the success of aseptic culture establishment. Sterile explants responded notably to 13.95 μM Kinetin (Kn) and 0.27 μM
α-naphthalene acetic acid (NAA), and a maximum of 38 ± 0.87 shoots per explant could be obtained after 6 weeks of incubation.
Sub-culturing of the shoot mass after 8 weeks of culture on the previously described medium to 8.88 μM 6-benzyladenine (BA)-
and 0.27 μM NAA-containing medium stimulated further multiplication, elongation and growth of each individual regenerant.
Efficient rooting was noted after 5 weeks of transfer on half-strength MS medium containing 4.93 μM IBA. Sequential hardening
as hydroponic cultures under culture room and glasshouse conditions led to almost 85 and 98% survival of the regenerants upon
transfer to pots and field, respectively. Unlike the original A. roxburghiana plants, the plants raised from tissue culture showed a total absence of inherent phytoplasma infection evaluated via inspection
of morphological features, PCR and microscopic observations. 相似文献
7.
Guohua Ma Jinfeng Lü Jaime A. Teixeira da Silva Xinhua Zhang Jietang Zhao 《Plant Cell, Tissue and Organ Culture》2011,104(2):157-162
Ochna integerrima is a medicinal and ornamental plant in Southeastern Asia. It has been listed as a rare and endangered species in China. Here
we studied the effects of plant growth regulators and their concentrations on the induction of somatic embryogenesis and shoot
organogenesis from leaf and shoot explants of O. integerrima for the first time. Cytokinins played a crucial role in somatic embryogenesis and shoot organogenesis. Among them, a higher
concentration of thidiazuron (10.0–15.0 μM TDZ) could induce both somatic embryogenesis and adventitious shoot formation whereas
low concentrations of TDZ (5.0 μM) could only induce adventitious shoots. However, 6-benzyladenine (BA at 5–15 μM) could only
induce adventitious shoots. Shoot explants induced more adventitious shoots and somatic embryos than leaf explants when cultured
on medium with the same concentration (5–15 μM) of TDZ or 15 μM BA. Medium containing 0.5 μM α-naphthaleneacetic acid and
8 μM indole-3-butyric acid and 0.1% activated charcoal could induce adventitious roots within 1 month. An efficient mass propagation
and regeneration system has been established. 相似文献
8.
The initiation and development of somatic embryos and organogenic shoots and corm-like structures (CLSs) from petiole-derived
calli of Amorphophallus rivieri Durieu were observed histologically. The petioles were cultured on Murashige and Skoog (MS) medium supplemented with 5.37 μM
α-naphthaleneacetic acid (NAA) and 4.44 μM N6-benzylaminopurine (6-BA) for callus induction. The shoot and corm organogenesis occurred from the compact calli when they
were transferred to a medium containing 0.54 μM NAA and 4.44 μM 6-BA. A combination of 13.57 μM 2,4-dichlorophenoxyacetic
acid (2,4-D) and 8.88 μM 6-BA or 24.18 μM NAA and 6.66 μM 6-BA was optimum for induction of somatic embryos, which failed
to produce plantlets because of their structural abnormalities. Shoot regeneration predominantly happened through organogenesis
although somatic embryogenesis infrequently occurred. The subepidermal cells of the compact callus converted to competent
cells and started divisions, which resulted in formation of the meristemoids. The meristemoid cells continued division to
develop into bud primordia. Subepidermal cells could also form the globular structures. Subsequently, these globoids developed
into CLSs from which plantlets regenerated during subculture. Meanwhile, the CLSs were capable to form cormels, which could
be a promising way for the propagation of A. rivieri. 相似文献
9.
Seabuckthorn (Hippophae rhamnoides) is a multipurpose small tree with unique berries of high nutritional and pharmaceutical values. A clonally propagated plant
originating from a 20-year-old tree of H. r. rhamnoides × mongolica hybrid cultivar Julia and seedling offspring of this cultivar were investigated regarding induction of shoot organogenesis
in leaf explants and in roots of intact seedlings, and induction of direct somatic embryogenesis in explants from shoot tissue.
The highest percentage of leaf explants showing shoot organogenesis was achieved (juvenile explants, 65%; adult explants,
75%) when incubated in Murashige and Skoog (MS) medium supplemented with either 4.5 μM of the phenylurea cytokinin thidiazuron
(TDZ) or 2.25 μM TDZ plus 2.2 μM 6-benzyladenine (BA), for juvenile and adult explants, respectively, both supplemented with
0.53 μM α-naphthaleneacetic acid (NAA). Juvenile explants developed on average 18 shoots per explant in the MS medium supplemented
with 4.5 μM TDZ, a four fold increase over those incubated on the medium supplemented with 2.25 μM TDZ and 2.2 μM BA. Adult
leaf explants grown on medium containing 2.25 μM TDZ and 2.2 μM BA medium produced 12 shoots per explant, while those grown
on medium containing 4.5 μM TDZ produced 5 shoots per explant. Shoot organogenesis was observed in roots of intact seedlings
pre-cultured on plain medium lacking nutrients (PM) or woody plant medium (WPM) salts and then grown on WPM salts supplemented
with 4.4 μM BA, 0.29 μM gibberrelic acid (GA3), and 57.0 μM indoleacetic acid (IAA). The number of shoots formed on each seedling
root system was ten fold higher when the pre-culture was in WPM medium indicating a promoting effect of mineral nutrients
in the pre-culture medium. Somatic embryogenesis was induced in both juvenile and adult leaf explants in 65 and 78% of the
explants, respectively, in MS-based medium supplemented with 2.0 μM N-(2-Chloro-4-pyridyl)-N
1-phenylurea (CPPU), 0.53 μM NAA and varying concentrations of BA. There was an interaction effect between MS salt strength
and BA concentration. The most effective medium for inducing somatic embryogenesis in juvenile explants contained half strength
MS salts and 2.2 μM BA and full strength MS salts and 13.2 μM BA for adult explants. 相似文献
10.
Angela Carra Maurizio Sajeva Loredana Abbate Mirko Siragusa Francesco Sottile Francesco Carimi 《Plant Cell, Tissue and Organ Culture》2012,109(2):373-381
A new technique to regenerate caper plants (Capparis spinosa L. subsp. rupestris) starting from flower explant is reported. In vitro plant regeneration was attempted using stigma, anthers and unfertilized
ovules of unopened flowers collected in the field. Plant regeneration was achieved from unfertilized ovules on MS medium supplemented
with 88 mM sucrose and 13 μM 6-benzyladenine (BA). New individuals obtained from unfertilized ovules were used as source material
for micropropagation and multiple shoots were obtained on MS medium supplemented with the adeninic cytokinin BA and the auxin
indole-3-butyric acid (IBA). Explants obtained in micropropagation step were used for rooting step under several treatments.
The best results (100% of rooted explants) were obtained when explants were dipped for 10 min in 50 μM IBA solution and successively
maintained in growth regulator free medium. New plants were vigorous, of good quality and presented phenotypic characters
similar to mother plants. Furthermore genetic stability of regenerants was verified through flow cytometric analysis and two
different DNA-based techniques. 相似文献
11.
Jin Cui Jianjun Chen Richard J. Henny 《In vitro cellular & developmental biology. Plant》2009,45(1):34-43
Plant regeneration through direct somatic embryogenesis in Aeschynanthus radicans ‘Mona Lisa’ was achieved in this study. Globular somatic embryos were formed directly from cut edges of leaf explants and
cut ends or on the surface of stem explants 4 wk after culture on Murashige and Skoog (MS) medium supplemented with N-phenyl-N′-1, 2, 3-thiadiazol-5-ylurea (TDZ) with α-naphthalene acetic acid (NAA), TDZ with 2,4-dichlorophenoxyacetic acid (2,4-D),
or 6-benzylaminopurine (BA) or kintin (KN) with 2,4-D. MS medium containing 9.08 μM TDZ and 2.68 μM 2,4-D resulted in 71%
of stem explants producing somatic embryos. In contrast, 40% of leaf explants produced somatic embryos when induced in medium
containing 6.81 μM TDZ and 2.68 μM 2,4-D. Somatic embryos matured, and some germinated into small plants on the initial induction
medium. Up to 64% of stem explants cultured on medium supplemented with 9.08 μM TDZ + 2.68 μM 2,4-D, 36% of leaf explants
cultured on medium containing 6.81 μM TDZ and 2.68 μM 2,4-D had somatic embryo germination before or after transferring onto
MS medium containing 8.88 μM BA and 1.07 μM NAA. Shoots elongated better and roots developed well on MS medium without growth
regulators. Approximately 30–50 plantlets were regenerated from each stem or leaf explant. The regenerated plants grew vigorously
after transplanting to a soil-less substrate in a shaded greenhouse with more than a 98% survival rate. Three months after
their establishment in the shaded greenhouse, 500 plants regenerated from stem explants were morphologically evaluated, from
which five types of variants that had large, orbicular, elliptic, small, and lanceolate leaves were identified. Flow cytometry
analysis of the variants along with the parent showed that they all had one identical peak, indicating that the variant lines,
like the parent, were diploid. The mean nuclear DNA contents of the variant lines and their parent ranged from 4.90 to 4.99 pg
2C−1, which were not significantly different statistically. The results suggest that the regenerated plants have a stable ploidy
level, and the regeneration method established in this study can be used for rapid propagation of ploidy-stable Aeschynanthus radicans. 相似文献
12.
Akula Ramakrishna Parvatam Giridhar Gokare Aswathanarayana Ravishankar 《In vitro cellular & developmental biology. Plant》2011,47(6):667-673
High-frequency somatic embryogenesis was achieved in Coffea canephora using calcium ionophore A23187, which influences the influx of calcium into a cell. With 100 μM calcium ionophore and 5 mM
calcium, 85% and 70% of cultures produced embryogenic tissue, with 105 ± 7 and 95 ± 8 primary embryos from each callus mass
respectively. Medium supplemented with 100 μM EGTA (calcium chelator) or 1 mM verapamil (calcium channel blocker) significantly
reduced somatic embryogenesis. Calcium imaging studies were done to determine the relationship between morphogenetic response
and the cellular calcium levels. The calcium ionophore/calcium treatment was very effective in driving cellular machinery
toward embryogenesis. The embryos were regenerated into plantlets when cultured on MS medium supplemented with 5 mM calcium/100 μM
calcium ionophore A23187. Somatic embryogenesis-derived plants were successfully transferred to soil and grown to maturity
in the field. 相似文献
13.
Murugesan Dhandapani Doo Hwan Kim Seung-Beom Hong 《In vitro cellular & developmental biology. Plant》2008,44(1):18-25
High-frequency plant regeneration of C. roseus cv. ‘little bright eye’ via somatic embryogenesis and organogenesis from five out of six explants was standardized. Two factors
were found to be important for regeneration: (1) the type of explants, and (2) the combination and concentrations of plant
growth regulators. The highest regeneration percentage through somatic embryogenesis was obtained from mature zygotic embryo
in MS medium supplemented with 7.5 μM of thidiazuron (TDZ). The mature embryo also regenerated efficiently via organogenesis
in MS medium supplemented with either 2.5 μM TDZ or 5.3 μM α-naphthalene acetic acid (NAA) and 2.2 μM 6-benzylaminopurine
(BA). Hypocotyl and cotyledon did not induce somatic embryogenesis and organogenesis in TDZ-containing medium but gave a maximum
percentage of shoots in MS medium supplemented with 5.3 μM NAA and 2.2 μM BA. Stem nodes and meristem tips showed better regeneration
via organogenesis in the medium supplemented with NAA and BA and in lower concentrations of TDZ. 相似文献
14.
Plant regeneration through somatic embryogenesis was achieved using immature zygotic embryos (ZE) of Sorbus pohuashanensis as explants. Over 50% of immature ZEs from immature seed collected at 30 days after pollination produced direct somatic embryos
(SEs) on Murashige and Skoog (MS) medium supplemented with 0–0.44 μM 6-benzyladenine (BA) in combination with 5.73 μM naphthaleneacetic
acid (NAA) or with 0.91–2.26 μM 2,4-dichlorophenoxyacetic acid (2,4-D) alone. Fourteen to 23 SEs per explant were regenerated
on MS medium supplemented with BA 0.44 μM in combination with NAA 5.73 μM. SE formation decreased when sucrose concentrations
were higher than 40 g L−1. Repetitive embryogenesis occurred following culture on solid MS medium containing 12 μM abscisic acid, 75 g L−1 polyethylene glycol, and 20 g L−1 sucrose at 25 ± 1°C under a 16-h photoperiod with a light intensity of 40 μmol m−2 s−1. Over 40% of the mature SEs germinated on solid MS medium under light condition described previously. Up to 40% of the regenerated
plantlets were successfully acclimatized under greenhouse conditions. Plantlets derived from SEs grew vigorously with similar
morphology as those germinated from ZEs. Histological studies of explants at various developmental stages of somatic embryogenesis
revealed that SEs passed through globular, heart, torpedo, and mature stages. Similar to ZE suspensors, similar structures
of SE degenerated in later stages of embryo development. ZE and SE are a effective means of regenerating tissue culture plantlets
for S. pohuashanesis. 相似文献
15.
Rubén Mallón Juan Rodríguez-Oubiña María Luz González 《Plant Cell, Tissue and Organ Culture》2010,101(1):31-39
The effect of different cytokinins on multiple shoot regeneration from shoots of Centaurea ultreiae was studied. The culture system consisted of solid basal half-strength Murashige and Skoog medium supplemented with one of
four cytokinins [6-benzyladenine (BA), zeatin, kinetin, or N6-(2-isopentyl) adenine (2-iP)] at each of five different concentrations. The highest multiplication rate (5.52 shoots per
explant) was obtained in the medium supplemented with 4.44 μM BA. Shoots were successfully rooted (91% success) by dipping
the basal end into a solution containing 10 M 1-naphthaleneacetic acid for 30 s. Genetic stability of the regenerated plants
was assessed by random amplified polymorphic DNA (RAPD) analysis and flow cytometry. In the initial randomly selected plant
material (control) and 20 of its regenerants, 2,688 bands were generated by RAPD with 12 different primers, and the same banding
profiles were exhibited. Molecular and cytological analyses did not reveal genomic alterations in any of the regenerated plants
obtained on medium containing 4.44 μM BA. The success of acclimatization to environmental conditions—100% of plants were successfully
acclimatized—suggests that the micropropagation system described is a reliable method for propagation of C. ultreiae. 相似文献
16.
M. A. K. Azad S. Yokota F. Begum N. Yoshizawa 《In vitro cellular & developmental biology. Plant》2009,45(4):441-449
Somatic embryogenesis and subsequent plant regeneration were established from hypocotyl and internode explants collected from
in vitro-grown seedlings and in vitro-proliferated shoots, respectively. Somatic embryogenesis was significantly influenced by the types of auxin and cytokinin.
Friable calluses with somatic embryos developed well in Murashige and Skoog basal (MS) medium supplemented with 0.8–8.8 μM
6-benzylaminopurine (BA) and 2.0–8.0 μM 2,4-dichlorophexoxyacetic acid (2,4-D) or α-naphthaleneacetic acid (NAA). The maximal
frequency of embryogenic callus and somatic embryo formation were obtained when the MS medium was amended with 8.8 μM BA and
4.0 μM 2,4-D. The best embryo germination occurred in a hormone-free 1/2-MS medium. The highest percentage of shoot proliferation
was observed in embryogenic calluses in MS medium containing 2.0 μM BA and 1.0 μM NAA. In vitro-grown shoots were rooted in MS medium with 0.5–2.0 μM indole-3-butyric acid. Regenerants were transferred to vermiculite and
successfully established under an ex vitro environment in garden soil. 相似文献
17.
A. Ptak A. El. Tahchy G. Wyżgolik M. Henry D. Laurain-Mattar 《Plant Cell, Tissue and Organ Culture》2010,102(1):61-67
The influence of ethylene on in vitro morphogenesis of Leucojum aestivum and galanthamine accumulation was studied. Calli were cultivated on Murashige and Skoog (MS) medium supplemented with 25 μM
4-amino-3,5,6-trichloropicolinic acid (picloram) and 0.5 μM benzyladenine (BA). During incubation under these conditions,
callus cultures produced ethylene (9.5 nL/g fresh weight: F.W.) whereas no ethylene was found in somatic embryos cultivated
on medium supplemented with 0.5 μM α-naphthalene acetic acid (NAA) and 5 μM zeatin. Application of the precursor of ethylene
1-aminocyclopropane-1-carboxylic acid (ACC) increased ethylene production in both cultures, and decreased callus growth by
a factor of 1.2, whereas callus growth was enhanced by a factor of 1.1 in the presence of an inhibitor of ethylene silver
nitrate (AgNO3) or by a factor of 1.2 with an absorbent potassium permanganate (KMnO4). ACC enhanced the induction of somatic embryos and the development of globular embryos. Removal of ethylene by KMnO4 during somatic embryogenesis led to the development of plants with greater length. Silver thiosulphate (STS) induced galanthamine
production in callus cultures (0.1% dry weight), whereas ACC induced galanthamine production in somatic embryo cultures (2%
dry weight). 相似文献
18.
A simple and efficient system was developed for rapid somatic embryogenesis from leaf explants of Merwilla plumbea, a traditional but threatened medicinal plant in South Africa. Friable embryogenic callus (FEC) was obtained from leaf explants
on embryogenic callus induction medium containing agar-solidified Murashige and Skoog (MS) salts and vitamins, 8.3 μM picloram,
2.3 μM thidiazuron (TDZ) and 20 μM glutamine. FEC was subsequently incubated in embryogenic callus proliferation medium containing
4.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.1 μM picloram for 7 days before it was transferred to liquid somatic embryo
medium (SEML) containing MS medium supplemented with 0.4 μM picloram and 0.9 μM TDZ. In SEML supplemented with 150 mg L−1 haemoglobin, 5.4–35.6 somatic embryos per settled cell volume of 500 mg FEC were obtained. These embryos were at globular
to cotyledonary developmental stages. Embryo maturation, germination and plant formation rate was 94.4% following transfer
of SEs to half-strength MS medium supplemented with 1.4 μM gibberellic acid. Plantlets transferred into soil acclimatized
in the misthouse and established successfully in the greenhouse (100%). This is the first report on induction of Merwilla plumbea somatic embryogenesis. The protocol developed offers controlled vegetative propagation by alleviating extinction threats,
ensures germplasm conservation and provides a system for physiological, biochemical, molecular and cellular studies of embryo
development. 相似文献
19.
Xingyu Yang Jinfeng Lü Jaime A. Teixeira da Silva Guohua Ma 《Plant Cell, Tissue and Organ Culture》2012,109(2):213-221
Primulina tabacum is a rare and endangered species that is endemic to China. Establishing an efficient regeneration system is necessary for
its conservation and reintroduction. In this study, when leaf explants collected from plants grown in four ecotypes in China
are incubated on Murashige and Skoog (MS) medium containing 5.0 μM thidiazuron (TDZ) for 30 days, then transferred to medium
containing 5.0 μM 6-benzyladenine (BA), adventitious shoots are then observed. Conversely, when leaf explants are incubated
on medium containing 5.0 μM BA for 30 days, then transferred to medium containing 5.0 μM TDZ, somatic embryogenesis is induced.
This indicates that somatic embryogenesis and shoot organogenesis could be switched simply by changing the order of two cytokinins
supplemented in the culture medium. Histological investigation has revealed that embryogenic cells are induced within 30 days
following incubation of explants in medium containing TDZ. Only if embryogenic cells were induced, TDZ could enhance somatic
embryogenesis and BA could stimulate shoot organogenesis. When comparing explants from different ecotypes, leaf explants
from Zixiadong in Hunan Province could induce low numbers (1–2) of either somatic embryos or adventitious shoots on medium
containing either 5.0 μM TDZ or 5.0 μM BA, respectively. Whereas, leaf explants from plants collected from the other three
ecological habitats could induce 50–70 somatic embryos/adventitious shoots per explant. Moreover, somatic embryos could induce
secondary somatic embryogenesis and adventitious shoots on different media. All regenerated shoots developed adventitious
roots when these are transferred to rooting medium, and over 95% of plantlets have survived following acclimatization and
transfer to a potting mixture (1:1, sand:vermiculite). 相似文献
20.
DNA-methylation changes in grapevine somaclones following in vitro culture and thermotherapy 总被引:1,自引:0,他引:1
Miroslav Baránek Břetislav Křižan Eva Ondrušíková Miroslav Pidra 《Plant Cell, Tissue and Organ Culture》2010,101(1):11-22
The methylation-sensitive amplified polymorphism (MSAP) technique using HpaII and MspI isoschizomers was used to analyse DNA-methylation alterations in stressed grapevine plants. The stress used was in vitro
propagation via nodal segments and in vitro thermotherapy for virus elimination. A set of pertinent grapevine plants derived
from two cultivars (18 plants each for Müller Thurgau and Riesling) was used as stressed variants for analyses. A total of
695 and 700 MSAP bands were recognised and evaluated as present/absent for all analysed variants derived from both cvs. Müller
Thurgau and Riesling. Average computed similarity of MSAP banding between analysed variants (Dice/Nei and Li coefficient)
was 0.935 for both cultivars. Clustering of variants within resulting dendrograms showed significant differences between woody
cuttings despite originating from the one plant. Further, there was a strong ‘donor’ effect of maternal plants on future arrays
of DNA methylation in their regenerants. The ‘donor’ effect even seemed to prevail in the effect of stress on final DNA-methylation
state in stressed regenerants. Additional MSAP evaluation suggests that thermotherapy induced an additional array of methylation
changes when compared with stress caused by in vitro cultivation. From the viewpoint of whether methylation of CCGG loci increased/decreased
due to stress, the results showed moderate prevalence for decreasing CCGG loci methylation. 相似文献