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1.
Qin-Mei Wang Feng-Zhan Gao Xiang Gao Fan-Yu Zou Xin Sui Meng Wang Yue-Jun Hui Li Wang 《Plant Cell, Tissue and Organ Culture》2012,109(2):191-200
An efficient in vitro micropropagation system for Clivia miniata Regel was developed using basal tissues of young petals and young ovaries as explants. For callus induction, explants were
incubated on Murashige and Skoog (MS) medium containing either 2.22 μM 6-benzyladenine (BA) and 4.52 μM 2,4-dichlorophenoxyacetic
acid (2,4-D) or 4.44 μM BA, 5.37 μM α-naphthaleneacetic acid (NAA), and 9.05 μM 2,4-D. Moreover, callus was induced from young
ovaries when these were incubated on MS medium containing 8.88 μM BA, 10.74 μM NAA, and 9.05 or 18.10 μM 2,4-D. Subsequently,
callus was transferred to MS medium supplemented with kinetin (KT) and NAA for shoot organogenesis. Frequency of shoot regeneration
from petal-derived callus was highest when callus was transferred to medium containing 2.69 μM NAA with either 9.29 or 13.94 μM
KT. Shoot regeneration frequency from ovary-derived callus was highest when this callus was transferred to medium containing
9.29 μM KT and 10.74 μM NAA. Overall, different explant types exhibited different organogenic capacities wherein, young petals
had higher shoot regeneration frequencies than young ovaries. The highest rooting frequency (98.25 ± 3.04%) was obtained when
shoots were transferred to half-strength MS medium without plant growth regulators. Regenerated plantlets were transplanted
to soil mix and acclimatized, yielding a 96.80% survival frequency. Only 0.6% of regenerated plantlets exhibited morphological
changes. The diploid status (2n = 22) of regenerated plantlets was determined using chromosome counts of root-tips. Moreover, inter-simple sequence repeats
were used to assess the genetic fidelity of regenerated plantlets. Overall, regenerated plants shared 90.5–100.0% genetic
similarities with mother plants and 89.0–100.0% similarities with each other. 相似文献
2.
Kottackal Poulose Martin A. K. Pradeep Joseph Madassery 《Acta Physiologiae Plantarum》2011,33(4):1141-1148
Trichopus zeylanicus subsp. travancoricus (known as Arogyapacha), an endangered ethnomedicinal plant of the Western Ghats of South India, serves as the major source
of the commercial drug Jeevani. The present study established a long-term high frequency in vitro propagation protocol for Arogyapacha. Callus obtained from
the branch–petiole explants cultured on Murashige and Skoog (MS) medium with 4.5 μM 2,4-dichlorophenoxyacetic acid upon subculture
to medium with different concentrations of 6-benzyladenine (BA) either alone or in combination with an auxin favoured shoot
morphogenesis. Medium with 13.3 μM BA alone facilitated high frequency shoot bud (mean of 93.2) formation. Medium with lower
concentrations of BA (4.4, 6.6 and 8.8 μM) alone or in combination with lower concentration of α-naphthaleneacetic acid (NAA)
or indole-3-butyric acid (IBA) favoured better shoot growth than 13.3 μM BA containing medium, but with reduced number of
shoot buds. Subsequent cultures on medium with lower concentrations of BA and also on MS basal media facilitated shoot formation
as well as growth of shoots. The shoot regeneration potential showed no decline up to 5 years. Culture of the in vitro-derived
whole branch–leaf explants on MS basal medium developed shoots directly from the node. On medium with 19.6 μM IBA, the whole
branch–leaf explants induced nodular callus from the node, which developed shoots later. Subsequent cultures on medium with
BA exhibited high frequency shoot formation. The transfer of shoots after 10–15 days culture on half-strength MS medium containing
2.7 μM NAA to half-strength basal medium induced a mean of 11.3 roots. Field survival of plantlets relied on the soil mix:
a 1:4 ratio of sand and red-soil exhibited the highest plantlets survival (86.6%). RAPD profile of the source plant and plants
regenerated from calli after 4 years showed no polymorphism. The established plantlets with morpho-floral features similar
to that of the source plants flowered normally and set fruits. 相似文献
3.
Vanilla planifolia is a tropical orchid mainly known for the aromatic flavor of its cured pods. Callus cultures were initiated from leaf and
nodal explants of V. planifolia. Leaf explants showed better callus initiation than the nodal explants with callus biomass production maximal when cultured
on Murashige and Skoog (MS) basal medium containing 4.52 mM 2,4-dichlorophenoxy acetic acid and 2.22 mM benzyladenine (BAP).
Callus transferred to MS basal medium supplemented with 13.32 μM BAP, and 13.43 μM naphthaleneacetic acid (NAA) showed superior
growth response and produced 14.0 ± 1.0 shoots with an average length of 3.6 ± 0.1 cm after 40 d. Subsequent transfer of the
proliferated shootlets to MS basal medium supplemented with 8.88 μM BAP and 8.08 μM NAA produced 12.3 ± 0.14 plantlets with
an average height of 3.6 cm ± 0.10 cm. All plantlets produced profuse rooting within 35–40 d after transfer to half-strength
MS basal medium supplemented with NAA in combination with indole-3-acetic acid. Rooted plantlets were transferred for hardening,
with 80% of the plantlets becoming successfully established in the field. Potentially, more than 100,000 plantlets could be
produced within eight subcultures from callus obtained from leaf explant through the methods described here. 相似文献
4.
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
5.
A novel protocol for callus-mediated shoot regeneration was established for an important medicinal and ornamental plant native
to South China, Curcuma kwangsiensis, using shoot base sections excised from seedlings in vitro as explant sources. The frequency of callus formation reached
91% for explants cultured on MS medium containing 1.4 μM TDZ, 4.4 μM BA and 2.3 μM 2,4-D. 8.2 shoots per callus was achieved
on MS medium supplemented with 1.4 μM TDZ, 17.8 μM BA and 2.7 μM NAA. Single shoots transferred into MS medium free of plant
growth regulator rooted well. Regenerated plants acclimatized ex vitro at 100%, and grew vigorously under shaded greenhouse
conditions. 相似文献
6.
Justicia gendarussa is a valuable medicinal plant and various parts of this plant are pharmaceutically used for the treatment of different diseases.
In vitro regeneration of shoot buds was obtained from culture of nodal cuttings as well as shoot regeneration from callus.
The nodal cuttings differed in shoot proliferation in terms of percentage of explants that responded and average shoot length
with various concentrations (4.4, 8.9, 13.3, 17.7, 22.2 μM) of 6-benzyladenine (BA), kinetin (Kn) and thidiazuron. In all
treatments, one shoot was invariably present. Optimum 87% of cultures responded with an average shoot length of 4.4 cm on
Murashige and Skoog (MS) medium supplemented with 17.7 μM BA. Callus was induced from the mature leaf segments on MS medium
supplemented with Kn (4.7, 13.9, 23.2 μM) alone or in combination with 2, 4-dichlorophenoxyacetic acid (2, 4-D; 2.3 μM, 4.5 μM).
Optimum callus induction (78%) was obtained on MS medium supplemented with 14 μM Kn and 4.5 μM 2, 4-D. When the callus was
subcultured on MS medium fortified with BA (8.9, 17.7, 26.6 μM) or Kn (9.3, 18.6, 27.9 μM) alone or in combination with α
naphthalene acetic acid (NAA; 2.7, 5.4 μM), shoot regeneration was obtained. The highest response (92%) was observed on MS
medium containing 17.7 μM BA and 5.4 μM NAA. On this medium, an average number of 12.2 shoots were obtained per responding
callus. The shoots obtained from callus and nodal cuttings were rooted with a frequency of 73% on MS medium augmented with
9.8 μM indole-3-butyric acid. The rooted shoots were successfully transplanted to soil and sand mixture (1:1) with 90% survival
rate. The protocol standardized for shoot proliferation and regeneration in J. gendarussa from nodal cuttings and leaf-derived callus is suitable for micropropagation and conservation of this essential medicinal
plant. 相似文献
7.
Kaitlin J. Palla Paula M. Pijut 《In vitro cellular & developmental biology. Plant》2011,47(2):250-256
A plant regeneration protocol was developed for white ash (Fraxinus americana L.). Hypocotyls and cotyledons excised from embryos were cultured on Murashige and Skoog (MS) medium supplemented with 6-benzylaminopurine
(BA) plus thidiazuron (TDZ), and compared for organogenic potential. Sixty-six percent of hypocotyl segments and 10.4% of
cotyledon segments produced adventitious shoots, with a mean number of adventitious shoots per explant of 3.5 ± 0.9 and 2.5 ± 1.5,
respectively. The best regeneration medium (52% shoot formation; 47% shoot elongation) for hypocotyls was MS basal medium
containing 22.2 μM BA plus 0.5 μM TDZ, producing a mean of 3.9 ± 0.4 adventitious shoots. Adventitious shoots were established
as proliferating shoot cultures following transfer to MS medium with Gamborg B5 vitamins supplemented with 10 μM BA plus 10 μM
TDZ. For in vitro rooting, woody plant medium with indole-3-acetic acid (IAA) at 0, 2.9, 5.7, or 8.6 μM in combination with 4.9 μM indole-3-butyric
acid (IBA) was tested for a 5- or 10-d dark culture period, followed by culture under a 16-h photoperiod. The best rooting
(78% to 81%) of in vitro shoots was obtained with a 5 d dark culture treatment on medium containing 2.9 or 5.7 μM IAA plus 4.9 μM IBA, with an average
of 2.6 ± 0.4 roots per shoot. Rooted plants were successfully acclimatized to the greenhouse. This adventitious shoot regeneration
and rooting protocol will be used as the basis for experimental studies to produce transgenic white ash with resistance to
the emerald ash borer. 相似文献
8.
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
9.
Summary A viable protocol has been developed for direct and indirect shoot regeneration of Vernonia cinerea. To establish a stable and high-frequency plant regeneration system, leaf and stem explants were tested with different combinations
of α-naphthalene acetic acid (NAA), indole-3-acetic acid (IAA), and benzylaminopurine (BA). Lateral buds on nodal explants
grew into shoots within 2 wk of culture in Murashige and Skoog (MS) basal medium supplemented with 20.9 μM BA. Excision and culture of nodal segments from in vitro-raised shoots on fresh medium with the same concentration of BA facilitated development of more than 15 shoots per node.
Similarly leaf, nodal, and internodal explants were cultured on MS basal medium supplemented with different concentrations
of BA, NAA, and IAA either alone or in combinations for callus induction and organogenesis. Shoot buds and/or roots were regenerated
on callus. Shoot buds formed multiple shoots within 4 wk after incubation in induction medium. Adventitious buds and shoots
proliferated when callus was cut into pieces and subcultured on MS basal medium containing 20.9 μM BA and 5.3 μM NAA. This combination proved to be the best medium for enhanced adventitious shoot bud multiplication, generating a maximum
of 50 shoots in 4 wk. This medium was also used successfully for shoot proliferation in liquid medium. Root formation was
observed from callus induced in medium containing 8.05–13.4 μM NAA. Regenerated shoots exhibited flowering and root formation in MS basal medium without any growth regulators. Plantlets
established in the field showed 85% survival and exhibited identical morphological characteristics as the donor plant. 相似文献
10.
Bimal Kumar Ghimire Chang Yeon Yu Ill-Min Chung 《Plant Cell, Tissue and Organ Culture》2012,108(3):455-464
A simple and efficient procedure was developed for in vitro propagation of Solanum aculeatissimum Jacq. using leaf and petiole explants cultured on Murashige and Skoog (MS) medium supplemented with α-naphthalene acetic
acid (NAA) and 6-benzyladenine (BA). Effects of various plant growth regulators, explant types, carbohydrates, and basal salts
on induction of adventitious shoots were also studied. Leaf explants appeared to have better regeneration capacity than petiole
explants in the tested media. The highest regeneration frequency (79.33 ± 3.60%) and shoot number (11.33 ± 2.21 shoots per
explant) were obtained in leaf explants in MS medium containing 3% sucrose and 0.8% agar, supplemented with 0.1 mg/l NAA and
2.0 mg/l BA, whereas petiole explants were more responsive to 0.1 mg/l NAA and 1.0 mg/l thiadiazuron. Developed shoots rooted
best on MS medium with 1.0 mg/l indole acetic acid (IAA), producing 18.33 ± 2.51 roots per shoot. Histological investigation
showed that the shoot buds originated mainly from epidermal cells of wounded tissues, without callus formation. The regenerated
plantlets were successfully acclimatized in a greenhouse, where over 90% developed into morphologically normal and fertile
plants. Results of flow cytometry analysis on S. aculeatissimum indicated no variation in the ploidy levels of plants regenerated via direct shoot formation and showed almost the same phenotype
as that of mother plants. This adventitious shoot regeneration method may be used for large-scale shoot propagation and genetic
engineering studies of S. aculeatissimum. 相似文献
11.
Federico A. Gutiérrez-Miceli Lourdes Arias Nicolás Juarez-Rodríguez Miguel Abud-Archila Aldo Amaro-Reyes Luc Dendooven 《In vitro cellular & developmental biology. Plant》2010,46(1):57-63
This paper reports on the optimum concentrations of naphthalene acetic acid (NAA) and 6-benzyladenine (BA) to stimulate callus
growth and NAA; kinetin and silver nitrate (AgNO3) for callus redifferentiation in Dianthus caryophyllus L. Meristems were excised and placed in MS medium with 30 g l−1 sucrose and 9.0 μM 2,4-d. Callus clusters were transferred to MS medium containing NAA (0, 1.7, 3.3, and 5.0 μM) and BA (0, 1.7, 3.3, and 5.0 μM)
for proliferation and to MS medium with 30 g l−1 sucrose, 2.5 g l−1 phytagel, kinetin (0, 33, and 66 μM); NAA (0, 7.95, and 15.9 μM) and AgNO3 (0, 23.54 and 47.08 μM) for shoot and root induction. Treatments were applied according to a Box–Behnken design. After callus
growth and redifferentiation, plants were incubated in the greenhouse at 18 ± 2°C for 4 wk and at 20–26°C for 4 wk. Finally,
plants were changed to near-commercial greenhouse conditions with different day (30–35°C) and night (16–24°C) temperatures.
Results showed better callus growth at higher NAA concentrations. A maximum callus weight was found with 5.0 μM NAA but without
BA. A maximum of 78% calluses with shoots was obtained with 15.9 μM NAA, 47.08 μM AgNO3, and 0.74 μM kinetin and 58% with roots with 15.7 μM NAA and 47.08 μM AgNO3, but without kinetin. The shoots obtained showed little hyperhydricity. Vigorous plants were obtained after gradual acclimatization
with an 80% survival rate under nursery conditions. 相似文献
12.
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
13.
Landi Sun Suiwen Hou Dali Wu Yingcong Zhang 《In vitro cellular & developmental biology. Plant》2008,44(5):396-400
This study describes a reliable protocol for callus induction and rapid mass propagation of the ecologically important plant,
Zygophyllum xanthoxylon (Bunge) Maxim. The optimum callus induction medium was Murashige and Skoog (MS) supplemented with 4.4 μM 6-benzylaminopurine
(BAP) and 2.7 μM α-naphthalene–acetic acid (NAA), on which the callus induction frequencies from different seedling explants
were all 100%. However, seedling-derived callus did not form regenerated shoots. In order to achieve shoot multiplication,
shoots were developed from cultured plumules, at an average of 3.1 shoots per explant, and the regenerated shoot tips were
further multiplied by subculture. The best shoot multiplication from shoot tips was achieved on MS supplemented with 5.4 μM
NAA and 22.2 μM BAP after 40 d of culture. Seventy-three percent of regenerated shoots formed roots when cultured on MS supplemented
with 8.6 μM IAA after 4 wk of culture. The plants that acclimatized successfully in sand flourished the following year, with
normal morphology and growth characteristics. 相似文献
14.
A simple, high-frequency and reproducible protocol for induction of adventitious shoot buds and plant regeneration from leaf-disc
cultures of Jatropha curcas L. has been developed. Adventitious shoot buds were induced from very young leaf explants of in vitro germinated seedlings
as well as mature field-grown plants cultured on Murashige and Skoog’s (MS) medium supplemented with thidiazuron (TDZ) (2.27 μM),
6-benzylaminopurine (BA) (2.22 μM) and indole-3-butyric acid (IBA) (0.49 μM). The presence of TDZ in the induction medium
has greater influence on the induction of adventitious shoot buds, whereas BA in the absence of TDZ promoted callus induction
rather than shoot buds. Induced shoot buds were multiplied and elongated into shoots following transfer to the MS medium supplemented
with BA (4.44 μM), kinetin (Kn) (2.33 μM), indole-3-acetic acid (IAA) (1.43 μM), and gibberellic acid (GA3) (0.72 μM). Well-developed shoots were rooted on MS medium supplemented with IBA (0.5 μM) after 30 days. Regenerated plants
after 2 months of acclimatization were successfully transferred to the field without visible morphological variation. This
protocol might find use in mass production of true-to-type plants and in production of transgenic plants through Agrobacterium/biolistic-mediated transformation. 相似文献
15.
Diwakar Aggarwal Anil Kumar M. Sudhakara Reddy 《Plant Cell, Tissue and Organ Culture》2010,102(1):45-52
An efficient shoot organogenesis system has been developed from mature plants of selected elite clones of Eucalyptus tereticornis Sm. Cultures were established using nodal explants taken from freshly coppice shoots cultured on Murashige and Skoog medium
containing 58 mM sucrose, 0.7% (w/v) agar (MS medium) and supplemented with 2.5 μM benzyladenine (BA) and 0.5 μM α-naphthaleneacetic
acid (NAA). Shoot organogenesis was achieved from leaf segments taken from elongated microshoots on MS medium supplemented
with 5.0 μM BA and 1.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D). The addition of cefotaxime to the medium promoted shoot
differentiation, whereas carbenicillin and cephalexin inhibited shoot differentiation. Maximum shoot bud organogenesis (44.6%)
occurred in explants cultured on MS medium supplemented with 5.0 μM BA, 1.0 μM 2,4-D and 500 mg/l cefotaxime. Leaf maturity
influenced shoot regeneration, with maximum shoot organogeneisis (40.5%) occurring when the source of explants was the fifth
leaf (14–16 days old) from the top of microshoot. Shoot organogenic potential also varied amongst the different clones of
E. tereticornis. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) analyses indicated clonal uniformity of
the newly formed shoots/plants, and these were also found to be true-to-type. 相似文献
16.
Golandam Sharifi Hassan Ebrahimzadeh Behzad Ghareyazie Mansour Karimi 《In vitro cellular & developmental biology. Plant》2010,46(3):274-280
Saffron (Crocus sativus L.) is a monocotyledonous plant propagated via corms, but recently several alternative methods have been reported. To find
the conditions suitable for saffron shoot formation from corms, the effect of different concentrations of the plant growth
regulatory cytokinins N6-benzyladenine (BA) and N-phenyl-1, 2,3-thidiazol-5-ylurea, commonly known as thidiazuron (TDZ), were compared. In all corm
explants, an average of 39.5 ± 5.1 shoots per corm were induced by 4.54 μM TDZ, whereas only 3.6-11.4% by BA. The outstanding
result in the shoot formation stage is the generation of globular, translucent structures that are morphologically similar
to globular embryos. To optimize the plant regeneration from the induced adventitious shoots obtained from the TDZ treatment,
the shoots were transferred to MS and B5 media supplemented with different concentrations and combinations of NAA and BA.
The highest rate of plant regeneration from developing shoots was observed in the B5 medium containing 2.22 μM NAA and 2.68 μM
BA. With optimized hormonal conditions, an average of 19.55 ± 5.75 shoots and 3.18 ± 1.5 roots per explants were obtained.
Based on this experiment, a simple, new and efficient protocol is presented to produce numerous plants from induced corm explants
of saffron. 相似文献
17.
The aim of this study was to develop a new micropropagation system for Cassia angustifolia Vahl., an important medicinal legume using root explant as starting material. Root explants taken from 30-day-old aseptic
seedlings were cultured on Murashige and Skoog (MS) medium supplemented with different plant growth regulators: 6-benzyladenine
(BA), kinetin (Kn), and thidiazuron (TDZ). Organogenic nodular calli obtained on MS + TDZ (1.0 μM) were transferred to shoot
regeneration medium supplemented with different cytokinins (BA, Kn or TDZ) either alone or in combination with auxin:indole-3-acetic
acid or α-naphthalene acetic acid. Maximum shoot regeneration frequency (90%) was obtained on MS + BA (2.5 μM) + NAA (0.6 μM)
wherein a maximum of 42.76 ± 1.47 shoot buds per explant were induced with a maximum conversion rate of 35.63 ± 0.75 shoots
per explant and average shoot length of 5.43 ± 0.20 cm. Elongated microshoots were successfully rooted under ex vitro conditions
by pulse treatment in 200 μM of indole-3-butyric acid for half an hour. Microshoots were rooted, acclimatized and hardened
off simultaneously in sterilized soilrite inside the growth room and then established in pots containing sterilized soil and
manure (1:1) and grown under greenhouse condition with 90% survival rate. The histological sections at different developmental
stages of shoot buds revealed the organization of nodular meristematic zone leading to the orientation and differentiation
of shoot buds in large number and thereafter conversion into healthy shoots. 相似文献
18.
Hongyan Dai Zhihong Zhang Xiuwu Guo 《In vitro cellular & developmental biology. Plant》2007,43(1):2-8
Hawthorn (Crataegus spp.) is an important plant with a long history as an ornamental and a source of medicine. A protocol is outlined for adventitious
bud regeneration from leaf and cotyledon explants of Chinese hawthorn (C. pinnatifida Bge. var. major N.E.Br.). Adventitious buds were induced on both the leaves of sprouting winter buds and the leaves of in vitro plants, but the percentage of bud regeneration from leaves of in vitro plants was very low—less than 6%. On N6 medium supplemented with 31.08 μM BA and 9.67 μM NAA, the percentages of bud regeneration
from leaves of sprouting winter buds of cultivars “Liaohong” and “Qiujinxing” were 31.4% and 17.6%, respectively. The regeneration
abilities of three kinds of cotyledon explants, immature cotyledon, mature cotyledon, and cotyledon leaf, were compared. The
percentage of bud regeneration from cotyledon leaves was higher. On MS media supplemented with 4.44 μM BA and 4.54–9.08 μM
TDZ, the percentages of bud regeneration from cotyledon leaves of cultivars “Qiujinxing” and “Xiajinxing” were 27.7 ± 7.8%
and 20.1 ± 4.7%, respectively, and the numbers of buds per explant were 5.9 ± 1.6 and 3.2 ± 0.7, respectively. On B5 medium
supplemented with 2.22 μM BA, 2.32 μM Kn, and 0.57 μM IAA, adventitious buds grew quickly and 80–100% of buds developed into
shoots. The shoots rooted successfully with the two-step rooting method. Ninety days after transplantation, more than 80%
plants were survived. This system of adventitious bud regeneration from leaf and cotyledon explants could be useful for the
genetic transformation and polyploidization of Chinese hawthorn. 相似文献
19.
Shoot bud regeneration was obtained from isolated leaflets of Albizia procera cultured on MS medium with various concentrations
of 6-benzyladenine (BA) and α-naphthaleneacetic acid (NAA). The highest numbers of adventitious buds were obtained on MS medium
supplemented with 10 μM BA and 1 μM NAA. The replacement of 7 g l-1 Difco bacto agar with 2.6 g l-1 Phytagel in the medium
enhanced adventitious bud regeneration. Further, addition of 15 μM silver nitrate promoted callus-free shoot regeneration
from leaf explants. The regenerated shoot buds were elongated on MS medium containing 0.01 μM BA and 1 μM NAA. Rooting was
obtained on modified MS medium supplemented with 2 μM IBA. To our knowledge this is the first report of direct regeneration
of shoots from leaflet explants in A. procera, and should help facilitate genetic transformation in this species.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
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