共查询到20条相似文献,搜索用时 31 毫秒
1.
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
2.
Yohana de Oliveira Fernanda Pinto André Luís Lopes da Silva Ivan Guedes Luiz Antonio Biasi Marguerite Quoirin 《In vitro cellular & developmental biology. Plant》2010,46(2):192-197
Melaleuca alternifolia is cultivated for the production of an essential oil useful in the cosmetic and pharmaceutical industries. Despite the economic
importance of this species, there is little knowledge about its in vitro propagation. The aim of this study was to establish an efficient protocol for micropropagation of M. alternifolia. With the goal of in vitro multiplication by axillary shoot proliferation, both solid and liquid MS and WPM media were tested with supplementation with
BA at 0, 0.55, 1.11, 2.22, 3.33, and 4.44 μM. The best result for shoot multiplication was obtained when either 0.55 μM BA
was added into solid MS medium or 1.11 μM BA was added into liquid MS medium, with 5.6 and 11.8 shoots per explant generated,
respectively. On solid or liquid WPM medium supplemented with 0.55 μM BA, the proliferation rates were 5.5 and 4.7, respectively.
Three auxins (NAA, IAA, and IBA) were tested at 0.53 and 2.64 μM during the rooting stage. Several sucrose concentrations
(15, 30, and 45 g L−1) were compared to a sucrose-free medium. Rooting performances on four culture media were then compared: MS, half-strength
MS (MS/2), MS + activated charcoal (AC), and MS/2 + AC. The results showed that auxin addition to culture medium is not necessary
for in vitro rooting. Rooted microcuttings from different culture media were acclimatized in a greenhouse, and the survival percentage was evaluated.
All shoots cultured in an auxin-free MS medium supplemented with sucrose (30 g L−1) produced roots, and all plants survived during acclimatization. Activated charcoal added in rooting medium reduced rooting
rates. 相似文献
3.
Xiuli Shen William S. Castle Frederick G. GmitterJr 《Plant Cell, Tissue and Organ Culture》2009,97(1):103-108
A suitable protocol for micropropagation of Casuarina hybrid, Casuarina equisetifolia L. × Casuarina glauca Sieber ex Spreng (C. e. × C. g.), was developed. When seeds without seed coats were cultured on 4 germination media, the optimal seed germination percentage
(91%) was obtained on 0.8% agar solidified water medium. Shoot multiplication was achieved by culturing 2-cm long epicotyls,
excised from germinated seedlings, on MS (Murashige and Skoog 1962) basal medium supplemented with BA (6-benzylaminopurine)
at 4.4, 8.8, 17.8 and 35.6 μM. The greatest percentage of axillary bud sproutings (87.5%), mean number of sprouts per explant
(3.8), and shoot length (3.2 cm) were achieved on MS medium supplemented with 17.8 μM BA. MS medium supplemented with 4 different
concentrations of IBA (indole-3-butyric acid) (4.3, 8.7, 13.0 and 17.4 μM) were used for rooting of in vitro grown shoots.
The highest rooting percentage (65.6%), mean number of roots per explant (2.5) and mean length of roots per explant (1.6 cm)
was achieved at 13.0 μM IBA. Rooted shoots grew well after transfer to a substrate of peat and pinebark (7:3) in the greenhouse. 相似文献
4.
Cao Dinh Hung Krystyna Johnson Fraser Torpy 《In vitro cellular & developmental biology. Plant》2006,42(6):548-552
Summary An efficient protocol for in vitro propagation of the valuable medicinal plant, Wasabia japonica (Miq.) Matsumura is described through shoot tip proliferation and direct regeneration. Multiple shoots were induced from
shoort tips cultured on Murashige and Skoog (MS) semi-solid medium containing various concentrations (0.5–50 μM) of N6-benzyladenine (BA), thidiazuron, kinetin, and zeatin. A comparison was made on shoot multiplication between semi-solid and
liquid culture media. Well-developed shoots were obtained using full-strength MS semi-solid medium containing 5.0 μM BA. However, the greatest shoot proliferation was achieved on either full- or half-strength MS liquid media supplemented
with 5.0 μM BA for 4 wk (15.3±0.9 and 15.0±0.7 shoots per explant, respectively), and on half-strength MS liquid medium for 6 wk (25.8±1.3
shoots per explant) in culture. In contrast, the maximum number of shoots per explant on full-strength MS semi-solid medium
was achieved with either 5.0 μM BA (10.4±0.6 shoots per explant) or 10.0 μM kinetin (10.9±0.8 shoots per explant). Fresh weight of explants and length of shoots derived from full-strength MS liquid
medium (1055±77 mg and 34.2±1.0 mm, respectively) were significantly higher than those derived from full-strength MS semisolid
medium (437.6±17.3 mg and 15.4±0.7 mm, respectively). Quarter-strength MS liquid medium had no significant difference in shoot
proliferation when compared to quarter-strength MS semi-solid medium. Elongated shoots were separated and rooted on half-strength
MS semi-solid media fortified with 1-naphthaleneacetic acid (NAA), indole-3-butyric acid (IBA), or indole-3-acetic acid (IAA)
ranging from 0.1 to 10.0 μM. Root formation was greatest with IBA when compared with IAA and NAA. One hundred percent of shoots were rooted on half-strength
MS medium with 5.0 μM IBA, while vigorous roots were obtained with 10.0 μM IBA. Micropropagated plantlets were successfully established in soil with 95% survival rate after heardening. 相似文献
5.
An efficient and rapid method for in vitro clonal propagation of Huernia hystrix was developed, resulting in shoot regeneration within 3 weeks of culture. This endangered medicinal and ornamental succulent
is in high demand. Multiple shoots were regenerated from stem explants (10 mm length) cultured on Murashige and Skoog (MS)
medium containing 3% sucrose and supplemented with a range of NAA (0.00–8.06 μM) and BA (4.44–22.19 μM) concentrations. A
100% shoot response with a multiplication rate of four shoots per explant was obtained on MS medium containing 5.37 μM NAA
and 22.19 μM BA. Callus produced at the base of the explant on the same medium showed root organogenic potential. The in vitro
regenerated shoots produced roots when transferred to half strength MS medium with or without auxin. The micropropagated plants
were easily acclimatized within 2 months under greenhouse conditions when potted in a soil and sand mixture (1:1; v/v) treated
with a fungicide (Benlate, 0.01%). More than 95% survival with no observable morphological variations was obtained. The developed
protocol provides a simple, cost-effective means for the conservation of endangered H. hystrix by clonal propagation within a short time. 相似文献
6.
Elisa Quiala María-Jesús Cañal Mónica Meijón Roberto Rodríguez Maité Chávez Luis Valledor Manuel de Feria Raúl Barbón 《Plant Cell, Tissue and Organ Culture》2012,109(2):223-234
Shoot-tips, collected from greenhouse-grown plants of Tectona grandis L. (teak), were incubated on a semi-solid Murashige and Skoog (MS) medium with 2% (w/v) sucrose, and supplemented with 4.44 μM
6-benzyladenine (BA). These were then transferred to a temporary immersion system (TIS) using liquid MS medium supplemented
with 0 (CK-free medium), 2.22, 4.44, 6.66 μM BA. High mean numbers of shoots per explant were obtained when explants were
grown on medium containing either 4.44 or 6.66 μM BA and yielding 7.7 and 10.3 normal shoots (NS)/explant, respectively. Moreover,
these high BA levels contributed to lower accumulation of phenolic compounds and deposition of lignin in vascular cells of
the teak shoots following histochemical analysis. Morphological analysis of proliferating shoots by scanning microscopy revealed
that leaves of shoots incubated on either CK-free medium, 2.22, or 4.44 μM BA had elliptical stomata; whereas, stomata of
leaves of shoots grown on medium containing 6.66 μM BA were primarily ring-shaped, raised, and open. Moreover, misshapen stomata
with broken epidermal layers of guard cells, typical of hyperhydric leaves, were also observed. When shoots were rooted ex
vitro by dipping in 492.1 μM indole-3-butyric acid (IBA) for 2 min, the frequency of rooting of shoots previously grown on
either CK-free medium or 2.22 μM BA (96.7 and 91.7%, respectively) was higher than that of shoots grown on semi-solid medium
(73%). Shoots from both TIS treatments developed good root systems, and all plantlets (100%) survived transfer to soil mix
and acclimatization in the greenhouse. Plantlets established from shoots grown on 6.66 μM BA showed the lowest frequency of
survival (60%). After 3 months, plants were transferred to field conditions. 相似文献
7.
Carmen Valero-Aracama Michael E. Kane Sandra B. Wilson Nancy L. Philman 《Plant Growth Regulation》2010,60(1):43-49
Benzyladenine (BA) is the only cytokinin to effectively induce shoot multiplication in vitro between genotypes of the important
dune grass species Uniola paniculata (sea oats). However, a significant genotype-specific negative carryover effect of BA on ex vitro acclimatization has been
observed. In the present study, the effects of multiplication media supplemented with meta-topolin (mT), a BA-analog, BA or no plant growth regulator, were compared on in vitro multiplication, rooting and ex vitro acclimatization
using easy- and difficult-to-acclimatize sea oats genotypes. Both genotypes exhibited similar in vitro shoot dry weight, number
of harvestable shoots and percent rooting when cultured under standard conditions (with 2.2 μM BA) or with an equimolar concentration
of mT. In addition, both genotypes exhibited similar ex vitro leaf length and shoot production under these two culture conditions.
However, ex vitro acclimatization of rooted microcuttings of the difficult-to-acclimatize genotype significantly increased
when produced on shoot multiplication medium containing mT rather than BA. Meta-topolin concentrations 10 μM or greater were inhibitory to in vitro rooting and acclimatization ex vitro of both genotypes.
Nevertheless, survival of the difficult-to-acclimatize genotype was significantly greater when cultured in the presence of
2.2 μM–30 μM mT, compared to 2.2 μM BA. Therefore, a potential solution to overcome the detrimental BA carryover effect on ex vitro survival
in sea oats is the substitution of BA with 2.2 μM mT for Stage II shoot multiplication. Use of mT may provide an efficient method to ensure in vitro propagation of a large number of diverse sea oats genotypes for dune
restoration. 相似文献
8.
Y. H. Dewir D. Chakrabarty E. J. Hahn K. Y. Paek 《In vitro cellular & developmental biology. Plant》2006,42(3):291-297
Summary A method for the micropropagation of Spathiphyllum cannifolium is presented using shoot tip proliferation onto Murashige and Skoog (MS) medium supplemented with different plant growth
regulator concentrations and combinations. The proliferation responses were significantly influenced by the cytokinin type
and concentrations. Supplementation of the medium with benzyladenine (BA; 4.44–13.32 μM) increased the shoot proliferation rate significantly as compared to other treatments. When cytokinins were used with auxin
(indole-3-butyric acid, IBA and naphthalene acetic acid. NAA), the number of shoots per explant increased in comparison with
treatments with BA alone. The largest number of shoots, 9.3 per explant, was obtained with 13.32 μM BA and 4.9 μM IBA. Different MS medium strengths and sucrose concentrations were used with the aim to stimulate in vitro shoot proliferation. Full MS medium with 30 gl−1 sucrose was found to be suitable for shoot tip culture of Spathiphyllum. Comparative studies between gelled medium and bioreactor culture [continuous immersion (with or without net) and temporary
immersion in liquid media using ebb and flood] revealed that shoot multiplication and growth were more efficient in continuous
immersion (with net) bioreactor with low cytokinin-supplemented media. Plantlets from the bioreactor were cultured hydroponically
for 30 d and 100% of plants were rooted and acelimatized successfully. Rapid and efficient multiplication rate in bioreactor
and successful transfer to greenhouse makes this protocol suitable for large-scale multiplication of this important foliage
plant. 相似文献
9.
An efficient micropropagation system via direct shoot organogenesis from hypocotyl segments of Embelia ribes Burm F. was developed. A high frequency (84%) of adventitious shoot induction was obtained on Murashige and Skoog (MS) medium
supplemented with additives (283.85 μM ascorbic acid [AA], 118.96 μM citric acid [CA], 142.33 μM cysteine, and 684.22 μM glutamine)
and 1.13 μM of thidiazuron (TDZ) after 4 weeks following culture. Further development of shoot primordia into well-grown shoots
of 4–5 cm in length was achieved by sub-culturing explants along with shoot primordia on MS medium supplemented with 0.44 μM
benzyl adenine (BA) and 0.49 μM indole butyric acid (IBA) for three sub-culture periods with an interval of 15 days between
them. The highest shoot multiplication was obtained when explants were incubated on MS medium supplemented with 2.2 μM BA
and 0.49 μM IBA in 4 weeks. All in vitro developed shoots, 3–4 cm in length, rooted when grown on half-strength MS basal medium
along with 2.47 μM IBA within 4 weeks. Moreover, 100% of shoots developed roots when these were treated with 4.93 μM IBA for
20 min and then transferred to pots containing soilrite mix and grown in the greenhouse. In vitro and ex vitro rooted plants
showed a survival of 85 and 95% respectively, during hardening in the greenhouse for a 6-week period. 相似文献
10.
L. Venkatachalam R. Thimmaraju R. V. Sreedhar N. Bhagyalakshmi 《In vitro cellular & developmental biology. Plant》2006,42(3):262-269
Summary Direct shoot and cormlet regeneration from leaf explants were obtained in triploid dessert banana cultivar Nanjanagud Rasabale
(NR) that is classified under the group ‘Silk’ and has the genotype AAB. The response for both cormlet and direct shool formation
was observed only in leaf explants obtained from shoots cultured in liquid medium but not in similar explants obtained from
shoots grown on gelled medium. Shoot initiation occurred after a sequential culture of leaf (sheath) explants on modified
Murashige and Skoog (MS) medium supplemented with different growth regulators. In the sequence, the leaf explants were cultured
first on medium with a high level (22.4 μM) of benzyladenine (BA), second on indolc-3-butyric acid (IBA) supplemented medium, and third on reduced BA medium under incubation
in the dark. The highest adventitious shoot regeneration in 24% of the explants, with the number of shoots ranging from 2
to 3 per explant, occurred in the explants incubated at the first step in medium with 22.4 and 0.198 μM IBA. Further growth and complete shoot formation occurred under incubation in a 16-h photoperiod. While keeping the culture
conditions constant and replacing BA with picloram (0.83–20.71 μM) in the initial step, adventious origin of cormlets occurred in 12% of the explants. However, when rhizome explants (also
obtained from shoots grown in liquid medium) were cultured with various growth regulators in the first step, medium containing
2,4,5-trichlorophenoxyacctic acid (7.82 μM) produced friable callus that re-differentiated into roots only. Physical forms of the medium, ie.e. agar-gelled or liquid,
imparted specific effects on the extent of multiplication of leaf-regenerated shoots with no differences in morphology and
growth patterns when compared to those of meristem-derived plants. 相似文献
11.
In vitro propagation of northern red oak (Quercus rubra) shoots was successful from cotyledonary node explants excised from 8-wk-old in vitro grown seedlings. Initially, four shoots per explant were obtained on Murashige and Skoog (MS) medium supplemented with 4.4 μM
6-benzylaminopurine (BA), 0.45 μM thidiazuron (TDZ), and 500 mg l−1 casein hydrolysate (CH) with a regeneration frequency of 64.7% after 3 wk. Subculturing explants (after harvesting shoots)
to fresh treatment medium significantly increased shoot bud regeneration (16.6 buds per explant), but the buds failed to develop
into shoots. A higher percentage (73.3%) of the explants regenerated four shoots per explant on woody plant medium (WPM) supplemented
with 4.4 μM BA, 0.29 μM gibberellic acid (GA3), and 500 mg l−1 CH after 3 wk. Explants subcultured to fresh treatment medium after harvesting shoots significantly increased shoot regeneration
(16 shoots per explant). Shoot elongation was achieved (4 cm) when shoots were excised and cultured on WPM supplemented with
0.44 μM BA and 0.29 μM GA3. In vitro regenerated shoots were rooted on WPM supplemented with 4.9 μM indole-3-butyric acid. A higher percentage regeneration response
and shoot numbers per explant were recorded on WPM supplemented with BA and GA3, than on MS medium containing BA and TDZ. Lower concentrations of BA and GA3 were required for shoot elongation and prevention of shoot tip necrosis. Each cotyledonary node yielded approximately 20
shoots within 12 wk. Rooted plantlets were successfully acclimatized. 相似文献
12.
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
13.
Dormant buds from a mature tree of Populus tremula ‘Erecta’ were incubated on a Murashige and Skoog (MS) medium supplemented with 1.0 μM thidiazuron (TDZ). Induced shoots were
then proliferated on medium of MS or Woody Plant Medium (WPM), or Driver and Kuniyuki Walnut (DKW) supplemented with varying
levels of benzyladenine (BA). Overall, shoots grown on MS medium supplemented with 1.25–2.5 μM BA exhibited the highest frequency
of shoot proliferation (>95%) and more than 60% of responding explants produced more than five shoots per explant. Shoot organogenesis
was induced from both leaf and petiole explants incubated on WPM medium containing BA, or TDZ, or zeatin. Among the different
cytokinins tested, zeatin induced the highest frequency (average 72.1%) of shoot organogenesis. None of explants survived
on media containing no cytokinins within 6–8 weeks following culture. Overall, a higher frequency of shoot regeneration was
obtained from petioles than from leaf explants. The highest frequency of regeneration was achieved when petioles were incubated
on WPM containing 10–20 μM zeatin. Addition of naphthaleneacetic acid (NAA) did not have a significant effect on shoot regeneration
in all treatments. Shoot organogenesis was directly induced from petiole explants without intervening callus. Regenerated
shoots were easily rooted on all tested media supplemented with 0.5 μM NAA. Rooted plants were transferred to potting mix
and grown in the greenhouse. 相似文献
14.
When cotyledonary explants, excised from in vitro germinated seedlings, of pomegranate (Punica granatum L.) were incubated on solid Murashige and Skoog (1962) medium supplemented with 21 μM naptheleneacetic acid (NAA) and 9 μM 6-benzyladenine (BA), 80% of explants developed callus.
A high frequency of shoot organogensis was obtained when explants were incubated on MS medium supplemented with 8 μM BA, 6 μM
NAA, and 6 μM giberrellic acid (GA3). However, adding 24 μM silver nitrate (AgNO3) to this medium markedly enhanced shoot regeneration frequency (63%) and mean number of shoots per explant (11.26) and length
of shoots (2.22 cm). Highest frequency of in vitro rooting, mean number of roots/shoot (4.32), and mean root length (2.71 cm)
were obtained when regenerated shoots were transferred to half-strength MS medium supplemented with 0.02% activated charcoal.
Well-rooted plantlets were acclimatized, and then transferred to soil medium. Moreover, when zygotic embryos of P. granatum, excised from seeds collected at 16 weeks following full bloom, were incubated on MS medium containing 30 g l−1 sucrose, 15% coconut water, 21 μM NAA, and 9 μM BA, they developed the highest frequency of embryogenic callus, clumps with
globular embryos, and mean number of both globular and heart-shaped embryos per callus clump. Subjecting zygotic embryo explants
to six-week dark incubation period was essential for embryogenic callus induction, and these were subsequently transferred
to 16 h photoperiod for further growth and development of somatic embryos. Germination of somatic embryos was observed when
these were transferred to MS medium was supplemented with 60 g l−1 sucrose. 相似文献
15.
Surya Prakash Johannes Van Staden 《In vitro cellular & developmental biology. Plant》2008,44(4):338-341
A method for in vitro regeneration of Searsia dentata from nodal and shoot tip explants derived from mature trees is outlined. Nodal explants produced multiple shoots from the
axis when cultured on Murashige and Skoog (MS) medium containing 3% sucrose supplemented with 0, 5, 7.5, 10, or 12.5 μM N
6-benzyladenine (BA). An average of 5.3 shoots was obtained from nodal explants on 10 μM BA. For shoot tip explants, however,
supplementation of α-naphthaleneacetic acid (NAA) with BA favored a caulogenic response. A maximum of 6.1 shoots were produced
per shoot tip explant on MS containing 7.5 μM BA plus 5.0 μM NAA. The in vitro-regenerated shoots produced roots when transferred
to full-strength MS medium containing 3% sucrose and 10 μM indole-3-butyric acid (IBA). The developed plantlets were transferred
initially to a mist house. After an initial acclimatization period of 3–4 mo, plantlets were shifted to the greenhouse where
they thrived for 9 mo. The standardized protocol for mass propagation of S. dentata should eliminate the dependence on natural stands of plants for traditional medicinal purposes, and will also serve as a
means of conservation as the species is heavily overexploited. 相似文献
16.
Mahendra Phulwaria Manoj K. Rai Harish Amit K. Gupta Kheta Ram N. S. Shekhawat 《Acta Physiologiae Plantarum》2012,34(1):299-305
An efficient and improved in vitro propagation method has been developed for Terminalia bellirica, a medicinally important tree from nodal explants of 10-year-old mature tree. Shoot multiplication was influenced not only
by cytokinin types, their concentrations and their interaction with auxin but also by successive transfer of mother explants
for different passages, subculture of excised shoots on fresh medium and different medium composition. MS medium containing
2.22 μM BAP was found to be the best for shoot multiplication in a single step. After excision of newly formed shoots, mother
explants successively transferred to the same medium produced maximum shoots per explant after IV passage. Further enhancement
in morphogenetic response occurred when excised shoot clumps (2–3 shoots) were subcultured on MS medium supplemented with
2.22 μM BAP, 1.16 μM Kn and 0.57 μM IAA. Half-strength MS medium supplemented with 24.60 μM IBA and 100 mg l−1 AC was most effective for rooting of the shoots. To reduce labor, cost and time, an experiment on ex vitro rooting was also
carried out and it was observed that highest percent shoots rooted ex vitro when treated with 2,460 μM IBA for 5 min. Plantlets
rooted in vitro as well as ex vitro were acclimatized successfully under the green house conditions. In comparison to plantlets
developed from in vitro rooted, percent survival of plants those rooted ex vitro was significantly higher. Use of ex vitro
rooting technique for plant production serves as a more economical option; therefore, present method can be used for large-scale
commercial production of this medicinally important tree. 相似文献
17.
Cultures of seven Daphne species: Daphne caucasica, D. cneorum, D. giraldii, D. retusa, D. jasminea, D. laureola and D. tangutica were established in vitro on MS/WPM based media. Five of the species responded best on MS-based media (D. tangutica, D. laureola, D. caucasica, D. retusa and D. giraldii), while the remaining two species performed best on WPM-based media (D. cneorum, and D. jasminea). Shoot proliferation was achieved from both apical and nodal explants. Shoots were sub-cultured from stock cultures, cut
into nodal explants 3–5 cm long and place vertically on basal media supplemented with different concentrations and combinations
of cytokinins and auxins. Individual species displayed different responses to the various cytokinins and auxins. Among species,
D. jasminea produced the greatest proliferation rate with an average of 7.84 + 0.6 shoots per explant on WPM supplemented with 2.32 μM
BA + 0.0045 μM TDZ + 0.054 μM NAA, while the best multiplication rate for the same species grown on the same media supplemented
with a single cytokinin (BA) and no auxin was 2.60 + 1.3 shoots per explant. Following multiplication, new shoots transferred
to the elongation trails and then 50–100 mm Shoots used for rooting experiments. Increased rooting efficiencies were observed
on in vitro-generated shoots with the two-layer medium or dipping methods over when PGRs were uniformly incorporated into
the medium. Maximum rooting frequencies (average) ranged from 59% in D. tangutica to 85% in D. jasminea. Following in vitro rooting, rooted shoots immersed in 0.01% solution of humates and planted into a standard horticultural
substrate composed and watered weekly with a solution containing half-strength MS salts. 相似文献
18.
An efficient, rapid and reproducible plant regeneration protocol was successfully developed for Cassia angustifolia using nodal explants excised from 14-day-old aseptic seedlings. Of the two cytokinins, 6-benzyladenine (BA) and thidiazuron
(TDZ) evaluated as supplements to Murashige and Skoog (MS) medium, TDZ at an optimal concentration of 5.0 μM was effective
in inducing multiple shoots. The highest rate of shoot multiplication was achieved on MS medium supplemented with 5.0 μM TDZ
and 1.0 μM indole-3-acetic acid (IAA) at pH 5.8. The regenerated shoots when subcultured on hormone free MS medium considerably
increased the rate of shoot multiplication and shoot length by end of fourth subculture passage. Rooting was achieved on the
isolated shoots using MS medium with 60 μM indole -3- butyric acid (IBA) and 1% activated charcoal for 1 week and subsequently
transferring the shootlets to half strength MS liquid media without IBA and activated charcoal. The in vitro raised plantlets
with well-developed shoot and roots were successfully established in earthen pots containing garden soil and grown in greenhouse. 相似文献
19.
Phillip A. Wadl Adam J. Dattilo Lisa M. Vito Robert N. Trigiano 《Plant Cell, Tissue and Organ Culture》2011,106(3):513-516
Pityopsis ruthii is an endangered herbaceous perennial species from the United States. In vitro multiplication of this species can be valuable
for germplasm conservation. Flower receptacles of P. ruthii were cultured on Murashige and Skoog medium (MS) supplemented with 11.4 μM indole-3-acetic acid (IAA) in combination with
2.2, 4.4 or 8.8 μM 6-benzyladenine (BA). Shoots were visible within 14–28 days and three plants were successfully rooted on
MS medium supplemented with 5.7 μM IAA. A two tailed t-test for paired-variates revealed that shoot regeneration on MS medium
amended with 11.4 μM IAA and 2.2 μM BA was significantly higher (P < 0.05) than on other treatments. Leaf explants were also cultured on MS not supplemented with growth regulators or supplemented
with 11.4 μM IAA in combination with 0, 2.2, 4.4 or 8.8 μM BA. Shoots were visible within 21–35 days and one plant was successfully
rooted on MS medium supplemented with 5.4 μM NAA. Shoot regeneration on MS medium augmented with 11.4 μM IAA and 2.2 μM BA
was significantly higher (P < 0.05) than the other treatments according to analysis of variance (ANOVA) with a rank transformation. Hyperhydricity and
rooting of shoots was problematic for explants derived from flower receptacles and leaf tissue, but viable plants were regenerated
using both explants sources indicating the potential role for micropropagation in the ex situ conservation of the species. 相似文献
20.
Ganeshan Sivanandhan Thankaraj Salammal Mariashibu Muthukrishnan Arun Manoharan Rajesh Sampath Kasthurirengan Natesan Selvaraj Andy Ganapathi 《Acta Physiologiae Plantarum》2011,33(6):2279-2288
An efficient mass multiplication protocol was developed for Withania somnifera (L.) Dunal from nodal explants of field-grown plants on Murashige and Skoog medium (MS) supplemented with 6-benzyladenine
(BA) [1.5 mg L−l], indole-3-acetic acid (IAA) [0.3 mg L−l] and with the addition of polyamine, spermidine (20 mg L−l) (shoot multiplication medium). A total of 46.4 shoots were obtained from nodal explants and they were elongated in the same
medium in a culture duration of 6 weeks. The elongated shoots produced roots in MS medium fortified with putrescine (20 mg L−l) after 4 weeks, and all the rooted plants were successfully hardened and acclimatized with a survival rate of 100%. An average
of 276 shoots (46 × 6) was produced when at least six nodal explants obtained from each of the 46 in vitro grown shoots were
cultured by microcutting method in the same shoot multiplication medium. On an average, 12,696 plants could be produced from
all the shoots (276 × 46) by microcuttings in a period of 7 months. HPLC revealed a significant increase in the quantities
of withanolide A, withanolide B, withaferin A and withanone in the leaves, stems, and roots of in vitro regenerated plants
compared to the field-grown parent plants. Ploidy analysis using flow cytometry revealed genetic stability of in vitro regenerated
plants. This protocol will be useful for scale-up production of withanolides on commercial scale. 相似文献