共查询到20条相似文献,搜索用时 15 毫秒
1.
In the micropropagation of woody plant species, adventitious root and shoot formation remain some of the major bottlenecks
due to their recalcitrance to in vitro manipulation. Some plant growth regulators may ameliorate these recalcitrant effects
and improve in vitro caulogenic and rhizogenic processes. Shoot induction on shoot meristems, hypocotyls and epicotyls was
evaluated using equimolar concentrations of benzyladenine (BA), meta-topolin (mT), meta-topolin riboside (mTR), and meta-methoxytopolin riboside (MemTR). Three auxins, indole-3-acetic acid (IAA), indole-3-butyric acid (IBA) and α-naphthalene acetic acid (NAA) were used in
the induction of adventitious roots. Moderately high shoot formation (62.7%) was achieved at a concentration of 8.0 μM mT after 8 weeks in culture. The highest number of adventitious shoots per explant (2.4 ± 0.3) and the longest shoots (23.5 ± 3.16 mm)
were recorded on 8.0 μM mT, though not significantly different from BA treatments. Most shoots progressively produced brown basal callus, which is
a potential sink for cytokinin conjugates that are inhibitory to further proliferation of adventitious shoots. Good adventitious
shoot formation occurred in 55% of hypocotyl explants on 8.0 μM mT. The highest rooting (91.6%) was achieved with IBA-treated shoots at a concentration of 4.0 μM. The use of mT and IBA provide an efficient micropropagation method for S. birrea, though further research is required especially in overcoming ex vitro plantlet survival challenges. 相似文献
2.
An efficient, rapid and large scale propagation of a multipurpose herb, Ocimum basilicum through in vitro culture of nodal segments with axillary buds from mature plants has been accomplished. Among the cytokinins,
6-benzyladenine (BA), thidiazuron (TDZ), kinetin (Kin) and 2-isopentenyl adenine (2-iP) tested as supplements to Murashige
and Skoog (MS) medium, 5.0 μM BA was optimum in inducing bud break. The highest rate of shoot multiplication was achieved
on half-strength MS medium supplemented with 2.5 μM BA and 0.5 μM indole-3-acetic acid (IAA) combination. The shoots regenerated
from TDZ supplemented medium when subcultured to hormone-free MS medium considerably increased the rate of shoot multiplication
and shoot length by the end of third subculture. For rooting, MS medium supplemented with 1.0 μM indole-3-butyric acid (IBA)
proved to be better than that supplemented with IAA or α-naphthalene acetic acid (NAA). The in vitro raised plantlets with
well developed shoots and roots were successfully established in earthen pots containing garden soil and were grown in greenhouse
with 90% survival rate. Chlorophyll a and b, carotenoids and net photosynthetic rate were measured in leaves during ex vitro
acclimatization at 0, 7, 14, 21 and 28 days. Firstly these parameters showed a decreasing trend but subsequently increased
after 7 days of acclimatization. These findings indicate that the adaptation of micropropagated plants to ex vitro conditions
is more extended in time than generally accepted. 相似文献
3.
Michael W. Bairu Wendy A. Stirk Karel Doležal Johannes van Staden 《Plant Cell, Tissue and Organ Culture》2008,95(3):373-379
The effect of the cytokinins mT (meta-topolin), mTR (meta-topolin riboside), MemT (meta-methoxy topolin) and MemTR (meta-methoxy topolin riboside) on micropropagation of banana cultivars ‘Williams’ and ‘Grand Naine’ was studied and compared to
BA (6-benzylaminopurine). In vitro cultures, at the third sub-culture level, were purchased from African Biotechnologies (Pty)
Ltd., South Africa. These were then sub-cultured on MS media containing 7.5, 15 and 30 μM of all the cytokinins tested. Results
recorded after 6 weeks of growth demonstrated that there were statistically significant differences between the parameters
analyzed for the treatments. Superior multiplication rates were recorded for mT and mTR treatments. This result was consistent when compared to BA at 22.2 μM (previously published standard concentration). Contrary
to previous findings with other species, these cytokinins inhibited rooting. The effect on somaclonal variation was not significantly
different when BA, mT and mTR were tested at the seventh multiplication cycle for ‘Williams’ banana. These results support the possible use of topolins
as an alternative to BA for Cavendish banana tissue culture. The role of these cytokinins on somaclonal variation however,
requires a more stringent investigation as the results obtained in this investigation could have been influenced by carry-over
effects from the initial cultures. 相似文献
4.
Michael W. Bairu Wendy A. Stirk Karel Dolezal Johannes Van Staden 《Plant Cell, Tissue and Organ Culture》2007,90(1):15-23
Benzyladenine (BA) is the most widely used cytokinin in the micropropagation industry due to its effectiveness and affordability.
It, however, has disadvantages such as genetic alteration and abnormal growth in some plants. Naturally occurring zeatin on
the other hand is not as widely used as BA and is far more expensive. The use of meta-topolin and its derivatives as alternatives to BA and zeatin, both of which frequently have negative effects in tissue culture
was investigated. In vitro grown Aloe polyphylla (an endangered medicinal and ornamental aloe) were cultured on full strength Murashige and Skoog basal medium with different
concentrations of cytokinins and solidified with 1% Bacteriological Agar (Oxoid No. 1). mT was the preferred cytokinin both in terms of multiplication rate and rooting. The optimum concentration that induced regeneration
and rooting is 5.0 μM. The problem of hyperhydricity was totally controlled. Plants rooted spontaneously in multiplication
medium, thus avoiding the extra rooting step of the protocol. More than 91% of the plants transferred to ex vitro conditions
were successfully acclimatized. 相似文献
5.
Nodal segments from field-grown culms were used as explants to develop a method of in vitro plantlet regeneration in Bambusa glaucescens Willd. through axillary bud proliferation. Shoot multiplication experiments were carried out with different concentrations
of benzyl adenine (BA) and kinetin (Kn), either singly or in combination. A synergistic effect of the two cytokinins was observed
and the best interaction giving the highest rate of shoot multiplication (4.00-fold) was obtained for a combination of 5 μM
BA and 15 μM Kn. The MS medium supplemented with 25 μM indole butyric acid (IBA) was most suitable for rooting of shoots.
Hardening and acclimatization was successful and plantlets are growing normally in soil. 相似文献
6.
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
7.
Claudia Simões Norma Albarello Cátia Henriques Callado Tatiana Carvalho de Castro Elisabeth Mansur 《Plant Cell, Tissue and Organ Culture》2009,98(1):79-86
Alternative methods for in vitro shoot culture of Cleome rosea, a Brazilian herbaceous species with ornamental value and medicinal potential, were evaluated. A protocol for rapid in vitro
multiplication of roots, a valuable source of medicinal compounds, was also developed. Stem explants were cultured in liquid
media (continuous immersion and paper bridge), while root explants were cultivated in continuous immersion and on solidified
media. The highest numbers of shoots, 20 ± 4.6 shoots/explant, were obtained from stem explants incubated in a continuous
immersion system in a liquid medium supplemented with 2.2 μM BA. Root explants cultivated in liquid media produced only hyperhydrous
adventitious shoots. However, these explants generated 5.8 ± 0.8 shoots/explant by indirect organogenesis when cultivated
on solidified medium supplemented with 2.2 μM BA. In addition, root multiplication was achieved in liquid medium in the presence
of α-naphthaleneacetic acid. Adventitious shoots developed on newly formed roots when inoculated on solidified medium supplemented
with 2.2 μM BA. Shoot microcuttings developed roots when transferred onto solidified MS medium without growth regulators.
Rooted microcuttings were efficiently acclimatized when transferred ex vitro. 相似文献
8.
Pruski Kris W. Lewis Tina Astatkie Tess Nowak Jerzy 《Plant Cell, Tissue and Organ Culture》2000,63(2):93-100
In vitro culture establishment, shoot proliferation and ex vitro rooting responses of chokecherry (Prunus virginiana L.), `Garrington', and pincherry (P. pensylvanica L.f), `Mary Liss' and `Jumping Pound', were examined using various combinations of growth regulators. Dormant winter buds
were used as explants. MSMO medium supplemented with 0.49 μM IBA and either 4.44 or 8.87 μM BA was found to be optimal for
culture initiation of both species and cultivars. GA3 (28.89 μM) significantly reduced (p=0.0001) the number of successfully established cultures. BA concentrations 8.87–12.82 μM gave optimal shoot proliferation
in chokecherry and 4.44 μM BA in both cultivars of pincherry. Auxin treatments were required for ex vitro rooting of approximately 10 mm long shoots in peat/perlite (1:1 v/v) mixture, at 25 °C, under mist. The best rooting (84%)
was obtained with IBA/NAA (9.80/2.69 μM). A commercial rooting powder, Rootone F, containing IBA/NAA (0.057/0.067%) mixture,
was also effective (75%). The ex vitro rooted plantlets did not require any additional acclimatization prior to transplanting to the regular greenhouse conditions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
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
10.
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
11.
Blanca P. Martínez-Bonfil Guadalupe Salcedo-Morales Alma R. López-Laredo Elsa Ventura-Zapata Silvia Evangelista-Lozano Gabriela Trejo-Tapia 《Plant Cell, Tissue and Organ Culture》2011,107(2):195-203
Castilleja tenuiflora is a medicinal plant that grows in pine–oak woods primarily in southern and central Mexico. It is highly valued for its medicinal
properties, which have been attributed to aucubin-like iridoids. In the present study, we developed an efficient protocol
for in vitro shoot proliferation and ex vitro rooting of C. tenuiflora. Using a colorimetric method, we determined total iridoid contents of various different tissues of propagated plants. The
shoots were induced from nodal explants cultured on Murashige and Skoog (MS) (1962) medium supplemented with indole-3-butyric
acid (IBA) (0 and 0.5 μM) and different concentrations of thidiazuron (TDZ), 6-benzyladenine (BA), or kinetin (KIN) (0–20 μM).
Of the cytokinins tested, KIN was more effective for shoot induction than TDZ or BA, and the highest shoot proliferation rate
was achieved with 5 μM KIN (4 shoots per explant). Plantlets were rooted on MS medium, nutrient solution, or potting mix,
alone or in combination with auxins. The best responses (100% rooting efficiency) were obtained by dipping shoots in half-strength
MS medium containing 7.5 μM IBA before transfer to potting mix. On average, each shoot formed 9 roots of 39.3 ± 3.8 mm in
length after 21 days. These roots appeared to be more functional than those that developed in nutrient solution, and were
associated with a high survival rate (95%) during acclimatization and cultivation in a greenhouse, where flowering occurred
after 4 months. Propagated plants accumulated iridoids, thus representing a potential source of pharmacologically useful compounds. 相似文献
12.
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
13.
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
14.
Mack Moyo Jeffrey F. Finnie Johannes Van Staden 《Plant Cell, Tissue and Organ Culture》2012,110(3):319-327
Pelargonium sidoides DC is a geophytic species with high demand in the pharmaceutical, aromatherapy, perfumery and cosmetic industries as a result of its unique phytochemistry. The aim of this study was to develop a clonal propagation system for P. sidoides using explants from mature plants, with particular emphasis on the regeneration potential of N6-benzyladenine (BA) and kinetin (KIN) compared to meta-topolin (mT), meta-topolin riboside (mTR) and meta-methoxytopolin riboside (MemTR). Standard colorimetric assays were used to quantify phenolic constituents of the in vitro plants. Cytokinins had a significant effect on shoot regeneration compared to the control. Meta-topolins had significantly higher shoot multiplication and in vitro growth indices compared to both BA and KIN. The highest shoot multiplication indices were obtained at 5.0???M MemTR >2.0???M mTR >2.0???M MemTR >2.0???M mT. Pelargonium sidoides was intolerant to high BA concentrations as indicated by the low number of shoots per explant (1.0?±?0.19) at 5.0???M. Generally, there was a significant increase in phenolic constituents for the CK treatments when compared to the control. Shoot length increased with increasing indole-acetic acid (IAA) and indole-butyric acid (IBA) concentrations whereas the response for ??-naphthalene acetic acid (NAA) increased to an optimum then decreased. The highest root biomass was achieved on 1.0???M IAA >2.0???M NAA >2.0???M IBA. The rooting response observed in control plants may be due to the influence of endogenous auxins. In vitro P. sidoides plants were successfully established under ex vitro conditions. In conclusion, meta-topolins were significantly better than BA and KIN in shoot multiplication and promoting in vitro plant growth. The current findings contribute to the increasing research data on the importance of topolins as credible alternatives to traditional CKs in micropropagation. 相似文献
15.
A protocol for in vitro propagation of Isodon wightii (Bentham) H. Hara from nodal segments was developed. Multiple shoots were successfully established on half strength MS medium
supplemented with 4.4 μM BA. Enhancement of shoot multiplication and elongation was achieved on half strength MS medium supplemented
with 4.4 μM BA and 1.4 μM GA3. The regenerated shoots were rooted successfully on half strength MS medium supplemented with 4.9 μM IBA. Acclimatization
of in vitro rooted shoots was successful. The in vitro regenerated plants grew well in the greenhouse without any phenotypic
changes. 相似文献
16.
An efficient regeneration protocol for rapid multiplication of Melia azedarach, an economically as well as medicinally important timber-yielding tree, was developed. Nearly 90% of the culture exhibited
axillary bud sprouting and multiple shoot formation from nodal segments derived from 20-year-old candidate plus tree on Murashige
and Skoog (MS) medium supplemented with 5 μM 6-benzyladenine (BA). The highest shoot regeneration frequency (92%), maximum
number of multiple shoots (19.7 ± 0.31) as well as shoot length (4.9 ± 0.08 cm) was induced from nodal explants on MS medium
amended with 5.0 μM BA, 0.5 μM indole-3-acetic acid (IAA) and 30 μM adenine sulfate (AdS). Addition of 250 mg l−1 ammonium sulphate, (NH4)2SO4, and 100 mg l−1 K2SO4, prevented defoliation and tip burning without affecting the number of shoots. The explant harvest period also influenced
the bud break and shoot sprouting from nodal segments. Repeated subculturing of nodal explants on fresh MS medium containing
lower concentration of BA (2.5 μM) along with IAA (0.5 μM), AdS (30 μM) and additives was found most suitable growth regulator
regime for achieving 1.2-fold increase in shoot multiplication rate. The percentage of shoot multiplication as well as the
number of shoots per node remained the same during first three subculture passages, afterwards a decline was recorded. About
90% of the in vitro regenerated shoots were successfully rooted ex vitro by giving a pulse treatment of 250 μM indole-3-butyric
acid for 15 min, followed by their transfer to thermocol cups containing soilrite. The raised plantlets were successfully
acclimatized first under culture room conditions, then to green house with 85% survival rate. 相似文献
17.
Berta E. Llorente Leonardo M. Juarez Nancy M. Apóstolo 《Plant Cell, Tissue and Organ Culture》2007,89(2-3):193-201
Trehalose is a stress protecting and reserve carbohydrate in a variety of organisms. The effect of trehalose on micropropagation
of jojoba [Simmondsia chinensis (Link) Schneider] was investigated using a modified Murashige–Skoog as the basal medium (BM). Proliferation rate was significantly
higher in explants grown on BM + 1 mM trehalose compared to that in the phytohormone control medium. In multiplication stage,
shoot proliferation rate of 4.8 was achieved in BM with 4.44 μM BA and 1 mM trehalose. The rooting induction with 14.7 μM
IBA had a significant effect on root regeneration; the highest rooting percentage (46.6%) was obtained with 7 days of induction.
The incorporation of trehalose to the IBA-rhizogenesis media decreased basal callus but with trehalose alone, root development
was scant. In vitro plants showed anatomical features typical for the acclimatization stage. 相似文献
18.
An in vitro cultivation protocol was developed for S. africana-lutea a species threatened by over collection due to its importance as an aromatic medicinal plant in the Western Cape of South
Africa. Adventitious shoot induction was most successful using hypocotyls as explants for propagation on Murashige and Skoog
(Physiol Plant 15:473–497, 1962) medium supplemented with 4.4 μM BA only; 2.7 μM NAA and 4.4 μM BA; or 2.9 μM IAA and 9.3 μM kinetin respectively. For continuous
subculture, IAA and BA (μM) at a ratio of 2.9:4.4 or 2.9:8.9 had the best regeneration potential producing approximately three
plantlets per nodal explant. Plantlets had 4–5 nodes that could be utilized for the following subculture phase to induce axillary
shoots. The tissue culture of S. africana-lutea not only favoured rapid multiplication but was also characterized by seasonal in vitro flowering that was in synchrony with
that of plants growing in the wild. This propagation regime has the capacity for producing 2000–3000 plants from one shoot
after 3 four-week long subculture cycles, making it highly attractive for implementation as an in vitro conservation strategy.
The micropropagated plants were easily acclimatized (88%) within a month after rooting in vitro and planted ex vitro in a
sand:soil:peat moss:vermiculite (1:1:1:1; v/v) mixture. 相似文献
19.
A. Gentile A. Frattarelli P. Nota E. Condello E. Caboni 《Plant Cell, Tissue and Organ Culture》2017,128(3):693-703
The role of 4.1 or 8.2 μM meta-topolin (mT) on shoot multiplication, rooting and ex vitro acclimatization of micropropagated Corylus colurna L., a promising non-suckering rootstock for hazelnut (Corylus avellana L.), was examined in comparison to N6-benzyladenine (BA), the most used cytokinin in tissue culture of Corylus spp. The influence of 8.2 μM mT and BA on photosynthetic pigments content and antioxidant enzymes activity, catalase (CAT) and guaiacol peroxidase (POD), in regenerated shoots, and on the preparation of the rootstock for micrografting was also evaluated. The highest shoot multiplication was recorded on medium containing 8.2 μM mT and an overall positive effect of mT on growth and quality of micropropagated shoots was found. The highest chlorophyll a content (1.236 mg g?1 fresh weight, FW) and chlorophyll a/b ratio (2.48), and the lowest total carotenoids content (0.292 mg g?1 FW) and CAT activity (25.8 μmol min?1 mg?1 protein) were detected after 8.2 μM mT application, while no significant differences were found in chlorophyll b content and POD activity between the two cytokinins. The best rhizogenesis response (98% for 4.1 μM and 100% for 8.2 μM mT) and ex vitro acclimatization competence (higher than 78%) were exhibited from shoots multiplied on mT. Furthermore, the multiplication of rootstock on mT allowed obtaining the highest (70%) response of successful micrografting. The present findings provide the first evidence of the successful applicability of mT in C. colurna tissue culture and development of micrografted plantlets. 相似文献
20.
Factors affecting successful establishment in vitro, rapid proliferation and rooting of apricot cultivar ‘Bebecou’ were studied. Ethanol and NaOCl were applied in several combinations for disinfection; chilling, plant growth regulators BA, IAA and GA3, antibiotics, different culture vessels and systems of subculture were evaluated for the optimization of shoot proliferation and the auxins NAA and IBA were assessed for root induction. The highest number of new microshoots/explant (18.7) was obtained in a culture medium supplemented with 2.2 μM BA+0.57 μM IAA after 300 h of chilling. The effect of GA3 (11.4 μM) on shoot proliferation was positive in combination with 4.4 or 8.9 μM BA. Shoot length and productivity were highest at 2.2 μM BA+11.4 μM GA3+0.57 μM IAA and at 2.2 μM BA+0.57 μM IAA, respectively and decreased as cytokinin concentration increased. The antibiotic ‘Na-cefotaxime’ had a minimal impact on shoot growth when used at the lowest concentration (250 mg l−1). Subculture every 2 weeks in a medium supplemented with 2.2 μM BA and 0.57 μM IAA was more efficient for shoot induction than alternation of 20 days culture in a propagation medium supplemented with 2.2 μM BA and 10 days culture in an elongation medium supplemented with 1.1 μM BA and 5.71 μM IAA. The highest number of roots/shoot (8.1) was recorded at 19.6 μM IBA. 相似文献