共查询到20条相似文献,搜索用时 953 毫秒
1.
An efficient protocol was established for regeneration of Desmodium motorium via somatic embryogenesis. Embryogenic calli were induced from cotyledon segments (6 mm, 16 days old) lacking embryo axis,
excised from seedlings grown in vitro on Murashige and Skoog (MS) medium supplemented with indole-3-acetic acid (IAA) (2.9 μM)
in combination with 6-benzyladenine (BA) (4.44 and 8.88 μM). Differentiation of embryogenic calli into globular and heart-shaped
somatic embryos was achieved on transfer to hormone-free MS medium. When incubated for 4 days on MS medium supplemented with
BA (8.88 μM), 95% of the globular and heart-shaped somatic embryos matured into torpedo and cotyledonary stages with minimum
(10%) abnormalities. Modified MS basal medium without hormones and containing half-strength macronutrients and 0.88 M sucrose
was suitable for germination of mature somatic embryos. Regenerated plantlets were successfully transferred to earthen pots
with survival rate of 50%. Secondary embryogenesis was observed when pre-existing somatic embryos at globular and heart-shaped
stages were cultured on MS medium supplemented with various concentrations of BA, adenine sulphate (AdS) and abscisic acid
(ABA) individually. 相似文献
2.
P. I. P. Perera V. R. M. Vidhanaarachchi T. R. Gunathilake D. M. D. Yakandawala V. Hocher J. L. Verdeil L. K. Weerakoon 《Plant Cell, Tissue and Organ Culture》2009,99(1):73-81
Coconut is a cross pollinating palm, propagated only by seeds. Tissue culture is the only vegetative propagation method available
for coconut. Consistent callogenesis was obtained by culturing unfertilised ovaries at -4 stage in CRI 72 medium containing
100 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.1% activated charcoal. Callusing was improved by application of 9 μM thidiazuron
(TDZ). Embryogenic calli were subcultured onto somatic embryogenesis induction medium containing 66 μM 2,4-D. Stunted growth
was observed in the somatic embryos after subculture onto CRI 72 medium containing abscisic acid (ABA). Maturation of somatic
embryos could be achieved in Y3 medium without growth regulators. Conversion of somatic embryos was induced by adding gibberellic acid (GA3) to conversion medium containing 5 μM 6-benzyladenine (BA) while 2-isopentyl adenine (2iP) increased the frequency of plant
regeneration. A total of 83 plantlets was produced from 32 cultured ovaries. 相似文献
3.
Cheng-Hao Li Bao-Guang Liu Tae-Dong Kim Heung-Kyu Moon Yong-Eui Choi 《Plant biotechnology reports》2008,2(4):259-265
Picea koraiensis, called Korean spruce, is an evergreen tree and found mostly in northeast Asia. In this study, plant regeneration via somatic
embryogenesis from open-pollinated immature zygotic embryos of nine genotypes of elite trees was established. Immature zygotic
embryos were cultured onto RJW medium modified from 505 medium with 21.48 μM NAA, 2.22 μM BA, and 2.32 μM KT. The average
frequency for all nine genotypes was 74.2%. Embryogenic calluses of the nine genotypes of elite trees were subcultured on
RJW basal medium containing 8.06 μM NAA, 1.11 μM BA, and 1.16 μM kinetin. The calluses of three lines, 3#, 9#, and 2#, were actively proliferated but others were not. Somatic embryogenesis was induced from the embryogenic callus in genotypes
of 3#, 9#, and 2# on RJW medium with ABA and 60 g l−1 sucrose. Cotyledonary somatic embryos were subjected to a drying process. The drying of embryos by uncapping the culture
bottle for 5 days on a clean bench resulted in a high frequency of germination of somatic embryos (87% in RJW medium). However,
plantlet conversion from germinated embryos was greatly reduced and the optimal medium for plant conversion was 1/2 WPM or
1/2 BMI medium. In conclusion, we have, for the first time, established a plant regeneration system via somatic embryogenesis
in the Korean spruce, which can be applied for rapid micropropagation of elite trees. 相似文献
4.
P. Giridhar Vinod Kumar G. A. Ravishankar 《In vitro cellular & developmental biology. Plant》2004,40(6):567-571
Summary A novel protocol has been developed for inducing somatic embryogenesis from leaf cultures of Decalepis hamiltonii. Callus was obtained from leaf sections in Murashige and Skoog (MS) medium supplemented with α-naphthaleneacetic acid (NAA)+N6-benzyladenine (BA) or 2,4-dichlorophenoxyacetic acid (2,4-D)+BA. Nodular embryogenic callus developed from the cut end of
explants on media containing 2,4-D and BA, whereas compact callus developed on media containing NAA and BA. Upon subsequent
transfer of explants with primary callus onto MS media containing zeatin and/or gibberellic acid (GA3) and BA, treatment with zeatin (13.68μM) and BA (10.65 μM) resulted in the induction of the highest number of somatic embryos directly from nodular tissue. The maturation of embryos
took place along with the induction on the same medium. Embryogenic calluses with somatic embryos were subcultured onto MS
basal medium supplemented with 4.56μM zeatin+10.65 μM BA. After 4wk, more extensive differentiation of somatic embryos was observed. The mature embryos developed into complete
plantlets on growth regulator-free MS medium. A distinct feature of this study is the induction of somatic embryogenesis from
leaf explants of Decalepis hamiltonii, which has not been reported previously. By using this protocol, complete plantlets could be regenerated through indirect
somatic embryogenesis or organogenesis from leaf explants in 12–16 wk. 相似文献
5.
Perera PI Hocher V Verdeil JL Doulbeau S Yakandawala DM Weerakoon LK 《Plant cell reports》2007,26(1):21-28
Unfertilized ovaries isolated from immature female flowers of coconut (Cocos nucifera L.) were tested as a source of explants for callogenesis and somatic embryogenesis. The correct developmental stage of ovary explants and suitable in vitro culture conditions for consistent callus production were identified. The concentration of 2,4-dichlorophenoxyacetic acid (2,4-D) and activated charcoal was found to be critical for callogenesis. When cultured in a medium containing 100 μM 2,4-D and 0.1% activated charcoal, ovary explants gave rise to 41% callusing. Embryogenic calli were sub-cultured into somatic embryogenesis induction medium containing 5 μM abscisic acid, followed by plant regeneration medium (with 5 μM 6-benzylaminopurine). Many of the somatic embryos formed were complete with shoot and root poles and upon germination they gave rise to normal shoots. However, some abnormal developments were also observed. Flow cytometric analysis revealed that all the calli tested were diploid. Through histological studies, it was possible to study the sequence of the events that take place during somatic embryogenesis including orientation, polarization and elongation of the embryos. 相似文献
6.
Summary High-frequency somatic embryogenesis and plant regeneration was achieved on callus derived from leaf (petiole and lamina)
and internode explants of Centella asiatica L. Growth regulators significantly influenced the frequency of somatic embryogenesis and plant regeneration. Calluses developed
on Murashige and Skoog (MS) medium fortified with 4.52 μM 2,4-dichlorophenoxyacetic acid (2,4-D) or 5.37 μM α-naphthaleneacetic acid (NAA), both with 2.32 μM kinetin (Kn), were superior for somatic embryogenesis. Callus developed on NAA and Kn-supplemented medium favored induction
and maturation of embryos earlier compared to that on 2,4-D and Kn. Embryogenic callus transferred from NAA and Kn-supplemented
medium to suspension cultures of half-strength MS medium with NAA (2.69 μM) and Kn (1.16 μM) developed a mean of 204.3 somatic embryos per 100 mg of callus. Embryogenic callus transferred from 2,4-D and Kn subsequently
to suspension cultures of half-strength MS medium with 2,4-D (0.45 μM) and Kn (1.16 μM) developed a mean of 303.1 embryos per 100 mg of callus. Eighty-eight percent of the embryos underwent maturation and conversion
to plantlets upon transfer to half-strength MS semisolid medium having 0.054 μM NAA with either 0.044 μM BA or 0.046 μM Kn. Embryo-derived plantlets established in field conditions displayed morphological characters identical to those of the
parent plant. 相似文献
7.
S. Zdravković-Korać D. Ćalić-Dragosavac B. Uzelac D. Janošević S. Budimir B. Vinterhalter D. Vinterhalter 《Plant Cell, Tissue and Organ Culture》2008,94(2):225-231
Somatic embryos of red horse chestnut, derived from cultures maintained through repetitive somatic embryogenesis for a few
years, were subjected to induction of secondary regeneration. The embryos were divided in four classes on the basis of their
size (I-1, II-5, III-10 and IV-30 mm), and sub-cultured on MS media containing 0, 1, 5 or 10 μM kinetin (Kin) or benzyladenine
(BA). The pathway of secondary regeneration, somatic embryogenesis or caulogenesis, depended on the primary somatic embryo
(PSE) stage of development. The embryogenic capacity declined and bud-forming capacity increased with the degree of PSE maturity.
The PSE of the Classes I and II produced only secondary somatic embryos (SSE), the Class III PSE formed both SSE and adventitious
buds, whereas the Class IV PSE developed almost solely adventitious buds. The process of secondary somatic embryogenesis was
most effective in the Class II PSE at 5 μM BA, and the process of adventive organogenesis was most effective in the Class
IV PSE at 10 μM BA. On plant growth regulator (PGR)-free medium, PSE of A. carnea followed the same pattern of adventive regeneration, as those cultured on cytokinin containing media. The cytokinins only
amplified the response, in a certain range of concentrations. BA promoted bud induction at a much higher rate than Kin, while
their embryogenic effect was similar. 相似文献
8.
Konstantin V. Kiselev Anna V. Turlenko Yuri N. Zhuravlev 《Plant Cell, Tissue and Organ Culture》2009,99(2):141-149
A somatic embryogenesis protocol for plant regeneration of northern red oak (Quercus rubra) was established from immature cotyledon explants. Embryogenic callus cultures were induced on Murashige and Skoog medium
(MS) containing 3% sucrose, 0.24% Phytagel™, and various concentrations of 2,4-dichlorophenoxyacetic acid (2,4-d) after 4 weeks of culture in darkness. A higher response (66%) of embryogenic callus was induced on 0.45 μM 2,4-d. Higher numbers of globular- (31), heart- (17), torpedo- (12), and cotyledon-stage (8) embryos per explant were obtained
by culturing embryogenic callus on MS with 3% sucrose, 0.24% Phytagel™, and devoid of growth regulators after 8 weeks culture
in darkness. Continuous sub-culturing of embryogenic callus on medium containing 2,4-d yielded only compact callus. Desiccation of embryos for 3 days in darkness at 25 ± 2°C followed by cold storage at 4°C in
darkness for 8 weeks favored embryo germination and development of plantlets. Cotyledon-stage embryos subjected to desiccation
and chilling treatment cultured on MS with 3% sucrose, 0.24 Phytagel™, 0.44 μM 6-benzylaminopurine (BA), and 0.29 μM gibberellic
acid germinated at a higher frequency (61%) than with 0.44 μM BA alone and control cultures. Germinated plantlets developed
a shoot and root, were acclimatized successfully, and maintained in a growth room for plantlet development. 相似文献
9.
Mehdi Bakhshaie Mesbah Babalar Masoud Mirmasoumi Ahmad Khalighi 《Plant Cell, Tissue and Organ Culture》2010,101(2):229-235
A somatic embryogenesis (SE) protocol was established for the regeneration of Lilium ledebourii (Baker) Boiss. whole plants using new vegetative bulblet microscales and transverse thin cell layers (tTCLs) of young bulblet
roots as the explant sources. Bulblets were induced from bulb scale explants cultured for at least 3 months in the dark on
Murashige and Skoog (MS) medium containing 3% sucrose, 0.8% agar, and different concentrations of α-naphthaleneacetic acid
(NAA), 6-benzyladenine (BA), and thidiazuron. Embryo-like structures were obtained from tTCL explants of 3-month-old bulblets
(excised from bulb scale explants) following culture on solid MS medium containing 3% sucrose and various concentrations of
NAA and BA for 3 months in the dark. Both the explant source and the type of plant growth regulators affected the differentiation
of somatic embryos. The highest percentage (65.55%) of embryogenesis was obtained from bulblet microscale tTCLs cultured on
solid MS medium containing 0.54 μM NAA and 0.44 μM BA. Plants with normal shoots and roots were obtained following a 3-month
culture of embryos on growth regulator-free MS medium at 25 ± 1°C under a 16/8-h light/dark photoperiod (light intensity 40 μmol m−2 s−1, cool-white fluorescent light). The plants were successfully acclimatized in the growth chamber. 相似文献
10.
Yongxue Yang Guofeng Liu Manzhu Bao 《In vitro cellular & developmental biology. Plant》2006,42(6):520-524
Summary A protocol of somatic embryogenesis and plant regeneration from petiole segments of Parthenocissus tricuspidata Planch. has been developed. Embryogenic tissue was induced on B5 (Gamborg) basal medium supplemented with 2.25–9.0 μM 2,4-dichlorophenoxyacetic acid, 500 mg l−1 casein hydrolysate (CH), and 0.1 gl−1 activated charcoal. Somatic embryos were induced on B5 medium containing various concentrations of benzyladenine (BA) (4.44,
6.66, and 8.88 μM) and α-naphthaleneacetic acid (NAA) (0, 0.54, and 1.61 μM) plus 500 mg l−1 CH. Ninety percent of normal somatic embryos were converted into plantlets directly on Murashige and Skoog (MS) medium free
of plant growth regulators. Shoots could be induced from abnormal somatic embryos on MS medium containing 4.44 μM BA, 0.05 μM NAA, and 500 mg l−1 CH. Genotypic differences were found in the process of somatic embryogenesis and plant regeneration. Histological analysis
confirmed the process of somatic embryogenesis. Regenerated plantlets with well-developed roots were successfully acclimatized
in greenhouse and all plants showed normal morphological characteristics. 相似文献
11.
P. Jha C. B. Yadav V. Anjaiah V. Bhat 《In vitro cellular & developmental biology. Plant》2009,45(2):145-154
An efficient in vitro plant regeneration protocol through somatic embryogenesis and direct shoot organogenesis has been developed for pearl millet
(Pennisetum glaucum). Efficient plant regeneration is a prerequisite for a complete genetic transformation protocol. Shoot tips, immature inflorescences,
and seeds of two genotypes (843B and 7042-DMR) of pearl millet formed callus when cultured on Murashige and Skoog (MS) medium
supplemented with varying levels of 2,4-dichlorophenoxyacetic acid (2,4-D; 4.5, 9, 13.5, and 18 μM). The level of 2,4-D, the
type of explant, and the genotype significantly effected callus induction. Calli from each of the three explant types developed
somatic embryos on MS medium containing 2.22 μM 6-benzyladenine (BA) and either 1.13, 2.25, or 4.5 μM of 2,4-D. Somatic embryos
developed from all three explants and generated shoots on MS medium containing high levels of BA (4.4, 8.8, or 13.2 μM) combined
with 0.56 μM 2,4-D. The calli from the immature inflorescences exhibited the highest percentage of somatic embryogenesis and
shoot regeneration. Moreover, these calli yielded the maximum number of differentiated shoots per callus. An efficient and
direct shoot organogenesis protocol, without a visible, intervening callus stage, was successfully developed from shoot tip
explants of both genotypes of pearl millet. Multiple shoots were induced on MS medium containing either BA or kinetin (4.4,
8.8, 17.6, or 26.4 μM). The number of shoots formed per shoot tip was significantly influenced by the level of cytokinin (BA/kinetin)
and genotype. Maximum rooting was induced in 1/2 strength MS with 0.8% activated charcoal. The regenerated plants were transferred
to soil in pots, where they exhibited normal growth. 相似文献
12.
Małgorzata Malik 《Plant Cell, Tissue and Organ Culture》2008,94(3):337-345
Alternative procedures for the production of Narcissus L. somatic embryos were investigated. Somatic embryogenesis was initiated on ovary explants isolated from cv. Carlton bulbs,
chilled for 12 weeks at 5°C. The explants were cultured on MS media with 3% sucrose and growth regulators: Picloram or 2,4-D
(10 or 25 μM) and BA (1 or 5 μM) for 12 weeks in the culture systems: continuous cultivation on solid media, continuous cultivation
in liquid media and sequential cultivation using cycles in liquid and solid media. Two types of somatic embryogenesis, indirect
and direct, were observed. The developmental pathway depended on the period of exposure to liquid media. Somatic embryos were
formed via embryogenic nodular callus on solid media. 2,4-D and BA stimulated the process. The 4-week and 8-week liquid medium
treatments resulted in the development of somatic embryos directly from the ovary explant tissue. The highest number of somatic
embryos was noted under the influence of 25 μM 2,4-D and 5 μM BA in explants cultivated for 8 weeks in liquid medium and then,
for 4 weeks, on solid medium. The effects of inoculum density on biomass increase and the formation of somatic embryos in
cultures obtained on a medium with 25 μM 2,4-D and 5 μM BA were also checked. The highest biomass increase was observed after
subculturing in liquid medium containing 0.5 μM NAA and 5 μM BA when the density of inoculum was 0.5 g/25 ml of the medium.
The highest number of somatic embryos was noted when the density of inoculum was 1.5 g/25 ml. 相似文献
13.
Summary
In vitro propagation of Quassia amara L. (Simaroubaceae) was attempted using mature and juvenile explants. Attempts to establish in vitro culture using leaf and internode explants from a plant more than 15yr old were unsuccessful due to severe phenolic exudation.
Plant regeneration through direct and indirect somatic embryogenesis was established from cotyledon explants. Murashige and
Skoog (MS) medium with 8.9 μM N6-benzyladenine (BA) and 11.7 μM silver nitrate induced the highest number (mean of 32.4 embryos per cotyledon) of somatic embryos. Direct somatic embryogenesis
as well as callus formation was observed on medium with BA (8.9–13.3 μM). Semi-mature pale green cotyledons were superior for the induction of somatic embryos. Embryos developed from the adaxial
side as well as from the point of excision of the embryonic axis. More embryos were developed on the proximal end compared
to mid and distal regions of the cotyledons. Subculture of callus (developed along with the somatic embryos on medium with
BA alone) onto medium containing 8.9 μM BA and 11.7 μM silver nitrate produced a mean of 17.1 somatic embryos. Primary somatic embryos cultured on MS medium with 8.9 μM BA and 11.7μM silver nitrate produced a mean of 9.4 secondary somatic embryos. Most of the embryos developed up to early cotyledonary stage.
Reduced concentration of BA (2.2 or 4.4 μM) improved maturation and conversion of embryos to plantlets. Ninety percent of the embryos converted to plantlets. The optimized
protocol facilitated recovery of 30 plantlets per cotyledon explant within 80d. Plantlets transferred to small cups were subsequently
transferred to field conditions with a survival rate of 90%. 相似文献
14.
D. H. Tejavathi M. D. Rajanna R. Sowmya K. Gayathramma 《In vitro cellular & developmental biology. Plant》2007,43(5):423-428
Somatic embryogenesis from cultures of shoot apices, cotyledon and young leaves of in vitro shoots of Agave vera-cruz Mill. was studied. Embryogenic callus was obtained when explants were cultured on Murashige and Skoog’s (MS) medium (1962)
supplemented with L2 vitamins, 4.52 μM 2,4-dichlorophenoxyacetic acid (2,4-d) or 5.37 μM ∝-naphthalene acetic acid (NAA). Somatic embryos differentiated from this embryogenic callus upon subculture
to maturation/conversion medium containing cytokinin either alone or with auxin and l-glutamine. The best combination of growth regulators for development of somatic embryos was found to be 5.37 μM naphthalene
acetic acid plus 0.91 μM zeatin and 40 g/l sucrose. The conversion frequency of somatic embryos to plantlets varied from 46–50%.
Rooted plantlets were transferred directly to pots containing a soil, sand, and manure mixture without any hardening phase
with 96–98% survival of the plantlets. Based on the histological observations, the potential origin of the somatic embryo
is discussed. 相似文献
15.
Daniela Lopes Paim Pinto Beatriz de Almeida Barros Lyderson Facio Viccini José Marcello Salabert de Campos Maurecilne Lemes da Silva Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2010,103(1):71-79
In this study, flow cytometric analysis was used to evaluate the genetic stability of Passiflora cincinnata Mast. plants regenerated via primary and secondary somatic embryogenesis. Embryogenic calli obtained from culturing zygotic
embryos on Murashige and Skoog (MS) medium containing 18.1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 4.4 μM benzyladenine
(BA) were transferred to differentiation medium. Torpedo and cotyledonary embryos were obtained. These primary embryos were
maintained on differentiation medium to generate secondary embryos. Conversion of primary and secondary embryos yielded 305
and 138 normal plants, respectively. Almost 90% of plantlets survived following acclimatization. Flow cytometric analysis
revealed that seed-derived plants had on average 3.01 pg nuclear DNA (2C), and all plants, except for a single plant regenerated
via primary embryogenesis, maintained their ploidy. This single plant contained more than twice the average DNA content: 6.21 pg
(4C). Epidermal stomata of leaves of the tetraploid plant were larger but lower in density than those of diploid plants, indicating
that stomatal characteristics are useful in distinguishing between diploid and tetraploid plants of passion fruit. In summary,
the procedure we employed to regenerated P. cincinnata plants via somatic embryogenesis generated mostly genetically true-to-type plants. 相似文献
16.
S. Paul A. Dam A. Bhattacharyya T. K. Bandyopadhyay 《Plant Cell, Tissue and Organ Culture》2011,105(2):271-283
A reproducible protocol for direct and indirect somatic embryogenesis was established in a small aromatic tree, Murraya koenigii. Embryogenic callus was obtained from 90% zygotic embryonic axis (ZE) and 70% cotyledon (COT) explants in Murashige and Skoog
(MS) basal medium supplemented with 8.88 μM 6-benzyladenine (BA) and 2.675 μM α-naphthaleneacetic acid (NAA). Globular somatic
embryos were induced and further matured from such embryogenic callus by subsequent culture on the same basal media containing
thidiazuron (TDZ) (2.27–9.08 μM). The highest frequency of somatic embryos (14.58 ± 0.42) was recovered from ZE-derived callus
after 6 weeks. The age and type of explant and concentration of TDZ played an important role in the development of somatic
embryos. Explants excised from 60-day-old seed differentiated from 96.67% of ZE explants and 86.67% from COT explants when
cultured on MS basal medium supplemented with 4.54 and 9.08 μM TDZ, respectively, after 4 weeks. The best result obtained
for the average frequency of somatic embryos (11.28 ± 0.32) was from ZE explants, which was significantly higher than COT
explants (7.34 ± 0.97). Most of the somatic embryos (above 95%), irrespective of their origin, germinated after 4 weeks in
1/2 MS basal media containing 2.32 μM kinetin (KN) and 1.07 μM NAA. Well-rooted plantlets were successfully acclimatized.
Histological analysis and scanning electron micrographs confirmed the initiation, development, and germination of somatic
embryos from both explants. 相似文献
17.
Jing Li Yang Bo Zhao Eun Soo Seong Myong Jo Kim Won Hee Kang Na Young Kim Chang Yeon Yu Cheng Hao Li 《Plant biotechnology reports》2010,4(4):261-267
We describe culture conditions for a high-efficiency in vitro regeneration system of Papaver
nudicaule through somatic embryogenesis and secondary somatic embryogenesis. The embryogenic callus induction rate was highest when
petiole explants were cultured on Murashige and Skoog (MS) medium containing 1.0 mg l−1 α-naphthaleneacetic acid (NAA) and 0.1 mg l−1 6-benzyladenine (BA) (36.7%). When transferred to plant growth regulator (PGR)-free medium, 430 somatic embryos formed asynchronously
from 90 mg of embryogenic callus in each 100-ml flask. Early-stage somatic embryos were transferred to MS medium containing
1.0 mg l−1 BA and 1.0 mg l−1 NAA to germinate at high frequency (97.6%). One-third-strength MS medium with 1.0% sucrose and 1.0 mg l−1 GA3 had the highest frequency of plantlet conversion from somatic embryos (91.2%). Over 90% of regenerated plantlets were successfully
acclimated in the greenhouse. Secondary somatic embryos were frequently induced directly when the excised hypocotyls of the
primary somatic embryos were cultured on MS medium without PGRs. Sucrose concentration significantly affected the induction
of secondary embryos. The highest induction rate (89.5) and number of secondary somatic embryos per explant (9.3) were obtained
by 1% sucrose. Most secondary embryos (87.2–94.3%) developed into the cotyledonary stage on induction medium. All cotyledonary
secondary embryos were converted into plantlets both in liquid and on semisolid 1/3-strength MS medium with 1.0% sucrose. 相似文献
18.
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
19.
Summary
In vitro regeneration of plants via somatic embryogenesis through cell suspension culture was achieved in horsegram. Embryogenic calluses
were induced on leaf segments on solid Murashige and Skoog (MS) medium with 9.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Differentiation of somatic embryos occurred when the embryogenic calluses were transferred
to liquid MS medium containing 2,4-D. Maximum frequency (33.2%) of somatic embryos was observed on MS medium supplemented
with 7.9 μM 2,4-D. Cotyledonary-torpedo-shaped embryos were transferred to liquid MS medium without growth regulators for maturation
and germination. About 5% of the embryos germinated into plants, which grew further on solid MS medium. The plants were hardened
and established in soil. Effects of various auxins, cytokinins, carbohydrates, amino acids, and other additives on induction
and germination of somatic embryos were also studied. A medium supplemented with 7.9 μM 2,4-D, 3.0% sucrose, 40 mg l−1
L-glutamine, and 1.0 μM abscisic acid was effective to achieve a high frequency of somatic embryo induction, maturation, and further development. 相似文献
20.
Veena Agrawal Pratima Rani Sardar 《In vitro cellular & developmental biology. Plant》2007,43(6):585-592
In vitro regeneration through somatic embryogenesis as well as organogenesis using cotyledon of a woody medicinal legume, Cassia angustifolia is reported. The cotyledons dissected from semi-mature seeds, if inoculated on Murashige and Skoog’s medium (MS) supplemented
with auxin alone or in combination with cytokinin, produced direct and indirect somatic embryos. A maximum of 14.36 ± 2.26
somatic embryos per 20 mg of explants including callus were produced in 70% cultures on MS medium with 2.5 μM benzyladenine
(BA) + 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Although the percentage of embryogenic cultures was higher (83.33%) at
10 μM 2,4-D + 1 μM BA, the average number of somatic embryos was much less (7.6 ± 0.85) at this level, whereas at 2.5 μM BA
and 5 μM 2,4-D, there was a simultaneous formation of both somatic embryos and shoots. The somatic embryos, although started
germinating on the same medium, developed into full plantlets only if transferred to MS basal with 2% sucrose. Cytokinins
alone did not induce somatic embryogenesis, but formed multiple shoots. Five micromolar BA proved optimum for recurrently
inducing shoots in the competent callus with a maximum average of 12.04 ± 2.10 shoots and shoot length of 2.26 ± 0.03 cm.
Nearly 91.6% shoots (2–2.5 cm in size) organized an average of 5.12 ± 0.58 roots on half strength MS + 10 μM indole-3-butyric
acid. All the plantlets have been transferred successfully to soil. Types of auxin and its interaction with cytokinin significantly
influenced somatic embryogenesis. 相似文献