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1.
Summary An improved protocol for shoot regeneration from hypocotyl segments of seedlings from open-pollinated seeds of lingonberry
(Vaccinium vitis-idaea L.) cultivars, ‘Ida’, ‘Splendor’, and ‘Erntesegen’, and a native clone from Newfoundland was developed. The effect of thidiazuron
(TDZ) on adventitious bud and shoot formation from apical, central, and basal segments of the hypocotyl was tested. Highly
regenerative callus was obtained from hypocotyl segments on modified Murashige and Skoog (MMS) medium containing 5–10 μM TDZ. A maximum of 10 buds and 12 shoots per apical segment for seedlings of cultivar ‘Ida’ regenerated on MMS containing
10 μM TDZ. Callus and bud regeneration frequency, callus growth, and number of buds and shoots per regenerating explant depended
not only on the specific segment of the hypocotyl, but also on parental genotype. Inhibition of shoot elongation by TDZ was
overcome by transferring shoot cultures to a shoot proliferation medium containing 1–2 μM zeatin. The optimal concentration of sucrose for shoot elongation was 20 gl−1. Shoots were rooted ex vitro on a 2 peat: 1 perlite (v/v) medium after dipping in 0.8% indole-3-butyric acid, and rooted plants acclimatized readily under
greenhouse conditions. 相似文献
2.
Summary Foliar nutrition has been conceived as a possible means of overcoming the recalcitrance of Prosopis chilensis (Molina) Stuntz explants to standard in vitro culture. The foliar uptake of cations (K from 20 gl−1 KNO3 and Ca from 50 gl−1 CaCl2), anions (NO3 from 50 gl−1 KNO3 and PO4 from 50 gl−1 NaH2PO4), and glucose from a 100 mg l−1 solution studied. All of the nutrients examined were absorbed. The efficacy of foliar nutrition in prolonging the vigor of
micropropagated P. chilensis shoot tips was compared with nutrients supplied as a liquid to the base of the stem (liquid) or as an agar-solidified medium
(agar). A foliar-feeding apparatus was constructed that employed pressurization of the medium reservoir to drive the medium
into the culture vessel with a passive return by a siphoning effect. The medium used was Murashige and Skoog with 30 gl−1 sucrose, 0.1 mgl−1 benzylaminopurine, and 1 mgl−1 indole-3-butyric acid. Over a 9-wk test period it was found that explants cultured by foliar nutrition performed significantly
better than those grown on agar for shoot length, nodal production, and leaf retention; and better than liquid MS for node
production. There was no significant difference among the three treatments in percentage survival, percentage rooting, or
the mean number of roots. 相似文献
3.
Summary Coconut (Cocos nucifera L.) plantlets grown in vitro often grow slowly when transferred to the field possibly, due to a limited photosynthetic capacity of in vitro-cultured plantlets, apparently caused by the sucrose added to growth medium causing negative feedback for photosynthesis.
In this paper, we tested the hypothesis that high exogenous sucrose will decrease ribulose 1,5-bisphosphate carboxylase (Rubisco)
activity and photosynthesis resulting in limited ex vitro growth. Plantlets grown with high exogenous sucrose (90 gl−1) had reduced photosynthetic activity that resulted in a poor photosynthetic response to high levels of light and CO2. These plantlets also had low amounts of Rubisco protein, low Rubisco activity, and reduced growth despite showing high survival
when transferred to the field. Decreasing the medium’s sucrose concentration from 90 to 22.5 gl−1 or 0 gl−1 resulted in increased photosynthetic response to light and CO2 along with increased Rubisco and phosphoenolpyruvate carboxylase (PEPC) activities and proteins. However, plantlets grown
in vitro without exogenous sucrose died when transferred ex vitro, whereas those grown with intermediate exogenous sucrose showed intermediate photosynthetic response, high survival, fast
growth, and ex vitro photosynthesis. Thus, exogenous sucrose at moderate concentration decreased photosynthesis but increased survival, suggesting
that both in vitro photosynthesis and exogenous sucrose reserves contribute to field establisment and growth of coconut plantlets cultured in vitro. 相似文献
4.
Summary
In vitro propagation systems by means of areole activation were developed for Turbinicarpus laui, T. lophophoroides, T. pseudopectinatus, T. schmiedickeanus subsp. flaviflorus, T. schmiedickeanus subsp. klinkerianus, T. schmiedickeanus subsp. schmiedickeanus, T. subterraneus, and T. valdezianus. In vitro-germinated seedlings were used as a primary source of explants. Multiple shoot formation from areoles was achieved for three
explant types (apical, lateral, and transverse), cultured on Murashige and Skoog (MS) basal medium supplemented with 3% sucrose,
10 gl−1 agar and several treatments with cytokinins. Efficiencies were in the range from 7.8 shoots per explant in T. valdezianus up to 19.7 shoots per explant in T. pseudopectinatus, using the best treatment for each species and in a single proliferation cycle. Four of the studied species responded best
when 6-benzylaminopurine (3.3–8.8μM) was used, while 6-(γ,γ-dimethylallylamino)purine (19.7–24.6μM) showed better results in two species. The two remaining species showed no significant differences in their response to both
cytokinins. Regarding explant type, the best results were obtained with transverse cuts for five species, with apical explants
for one species, and the two remaining species showed no significant differences among the explants tested. Rooting of the
in vitro-generated shoots was achieved most efficiently on half- or full-strength MS basal medium. Rooting frequencies were in the
range from 54.2 to 94.2%, and the frequency of survival of the plants once transferred to soil was 91.6% on average. 相似文献
5.
This paper describes multiple shoot regeneration from leaf and nodal segments of a medicinally important herb Centella asiatica L. on Murashige and Skoog’s (MS) medium supplemented with a range of growth regulators. The highest number of multiple shoots
was observed on MS augmented with 3.0 mg dm−3 N6-benzylaminopurine (BAP) and 0.05 mg dm−3 α-naphthaleneacetic acid (NAA). Leaf explant showed maximum percentage of cultures regenerating shoots (81.6 %), with the
highest shoot number (8.3 shoots per explant) and the shoot length (2.1 cm) whereas, nodal explant showed less number of shoots
with callus formation at the base cut end. Successive shoot cultures were established by repeatedly sub-culturing the original
explant on a fresh medium. Rooting of in vitro raised shoots was best induced on half strength MS supplemented with 0.5 mg dm−3 indole-3-butyric acid (IBA) with highest percentage of shoot regenerating roots (76.8 %) with 3–4 roots per shoot. Plantlets
were acclimated in Vermi-compost and eventually established in soil. Contents of chlorophyll, total sugars, reducing sugars and proteins were estimated in
leaf tissue from both in vivo and in vitro raised plants. Chlorophyll content was higher in in vivo plants, whereas other three components were higher in in vitro plants. 相似文献
6.
Eline Kirk Mørk Karin Henriksen Henrik Brinch-Pedersen Kell Kristiansen Karen Koefoed Petersen 《Plant Cell, Tissue and Organ Culture》2012,108(3):501-512
A protocol for adventitious shoot formation in Symphyotrichum novi-belgii was developed after investigating the effects of cultivar and hormone combinations. A Murashige and Skoog medium with 1.0 mg l−1 6-benzyladenine induced adventitious shoot formation in 15 out of 19 cultivars. Addition of 0.1 mg l−1 indole-3-acetic acid or naphthaleneacetic acid increased the total number of shoots per explant, but not the number of shoots
longer than 1 cm. Addition of dichlorophenoxyacetic acid (2,4-D) promoted callus formation, but inhibited shoot elongation.
A transformation system for the two cultivars Victoria Fanny and Victoria Jane was developed by co-cultivation of leaf explants
with Agrobacterium tumefaciens. Three bacterial strains (LBA 4404, A281 and C58) all carrying the binary vector, p35S-GUS-INT, and harbouring the uidA gene coding for β-glucuronidase (GUS) were used. Regeneration of transgenic plants after co-cultivation with A281 was independent
of cultivar, and all explants produced callus followed by indirect shoot formation. In ‘Victoria Fanny’ shoots were formed
faster and without a callus phase after co-cultivation with LBA 4404 or C58. The highest number of potentially transformed
shoots was regenerated after co-cultivation of ‘Victoria Fanny’ leaf explants with LBA 4404. Integration of the transgenes
in the plant genome was confirmed using PCR and Southern blot hybridisation. To verify that the transgenes could be transferred
to offspring, crosses were conducted between three transgenic lines of ‘Victoria Fanny’ and two wild type pollen donors. It
was demonstrated that viable seeds were produced and that the uidA gene was inherited. 相似文献
7.
Branka Vinterhalter Dijana Krstić Milošević Teodora Janković Jelena Milojević Dragan Vinterhalter 《Central European Journal of Biology》2012,7(4):690-697
Gentiana dinarica Beck, rare and endangered species of Balkan Dinaric alps, was in vitro propagated (micropropagated) from axillary buds of plants collected at Mt. Tara, Serbia. G. dinarica preferred MS to WPM medium, with optimal shoot multiplication on MS medium with 3% sucrose, 1.0 mg l−1 BA and 0.1 mg l−1 NAA. Rooting was not clearly separated from shoot multiplication since BA did not completely inhibit root initiation. Spontaneous
rooting on plant growth regulator-free medium occurred in some 30% of shoot explants. Rooting was stimulated mostly by decreased
mineral salt nutrition and a medium with 0.5 MS salts, 2% sucrose and 0.5–1.0 mg l−1 IBA was considered to be optimal for rooting. Rooted plantlets were successfully acclimated and further cultured in peat-based
substrate. 相似文献
8.
Lihui Zeng Haifeng Xu Yunqi Zeng Aiye Luan Huiquang Wang 《In vitro cellular & developmental biology. Plant》2009,45(5):559-564
Ponkan mandarin (Citrus reticulata Blanco) is one of the most important commercial cultivars of mandarin orange in China. This study reports an improved and
efficient protocol for in vitro plant regeneration of Ponkan mandarin. Epicotyl segments, which were cut longitudinally into two halves, were used as explants.
The shoot regeneration frequency was significantly increased by longitudinal cutting. A 100% shoot regeneration frequency
and 13.2 shoots per explant were obtained when cultures were maintained in darkness for 20 d before being transferred to light
conditions, with bud induction by indirect organogenesis. A 72.5% shoot regeneration frequency and 7.8 shoots per explant
were obtained when explants were incubated under a 16-h light photoperiod continuously with buds differentiating directly
from the cutting wound surface. The optimal medium for shoot formation was Murashige and Tucker basal medium supplemented
with 2 mgL−1 BA and 30 gL−1 sucrose both under light conditions. The addition of the auxin NAA reduced the frequency of regeneration. A “filter-paper
bridge” technique was used for rooting in this study. The basal portion of regenerated shoots was dipped into 1,000 mgL−1 IBA solution for 15 min before placement on a filter-paper bridge that was maintained in 1/2 MS liquid medium supplemented
with 10 gL−1 sucrose. Eighty percent of the shoots rooted, and an average of 2.0 roots per shoot were achieved. Survival rate through
acclimatization was 100%. 相似文献
9.
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
10.
Ely Zayova Ira Stancheva Maria Geneva Maria Petrova Rumiana Vasilevska-Ivanova 《Central European Journal of Biology》2012,7(4):698-707
An effective in vitro protocol for rapid clonal propagation of Echinacea purpurea (L.) Moench through tissue culture was described. The in vitro propagation procedure consisted of four stages: 1) an initial stage - obtaining seedlings on Murashige and Skoog (MS) basal
medium with 0.1 mg L−1 6-benzylaminopurine, 0.1 mg L−1 α-naphthalene acetic acid and 0.2 mg L−1 gibberellic acid; 2) a propagation stage — shoot formation on MS medium supplemented with 1 mg L−1 6-benzylaminopurine alone resulted in 9.8 shoots per explant and in combination with 0.1 mg L−1 α-naphthalene acetic acid resulted in 16.2 shoots per explant; 3) rooting stage — shoot rooting on half strength MS medium
with 0.1 mg L−1 indole-3-butyric acid resulted in 90% rooted microplants; 4) ex vitro acclimatization of plants. The mix of peat and perlite was the most suitable planting substrate for hardening and ensured
high survival frequency of propagated plants. Significant higher levels were observed regarding water-soluble and lipid-soluble
antioxidant capacities (expressed as equivalents of ascorbate and α-tocopherol) and total pnenols content in extracts of Echinaceae flowers derived from in vitro propagated plants and adapted to field conditions in comparison with traditionally cultivated plants. 相似文献
11.
Elif Aylin Ozudogru Ergun Kaya Emrah Kirdok Saliha Issever-Ozturk 《In vitro cellular & developmental biology. Plant》2011,47(2):309-320
An efficient in vitro propagation protocol, applicable both to young and mature explants of two Thymus spp., results in genetically stable plantlets. In vitro-grown shoot tips of Thymus vulgaris L. were exposed to cytokinins (6-benzyladenine, kinetin, and thidiazuron) alone or in combination with auxins, gibberellic
acid (GA3) and/or silver nitrate in order to optimize in vitro shoot proliferation. Optimum shoot proliferation (97% regeneration rate, with 8.6 shoots produced per explant) was obtained
when semi-solid Murashige and Skoog (MS) medium was supplemented with 1 mg L−1 kinetin and 0.3 mg L−1 GA3. Rooting of the shoots was easily obtained on semi-solid MS medium that was either hormone-free or supplemented with auxins.
However, the best root apparatus (92.5% rooting rate, with 19 adventitious roots per shoot) developed on MS medium supplemented
with 0.05 mg L−1 2,4-dichlorophenoxyacetic acid. Genetic stability was confirmed in the in vitro-germinated mother plant as well as the shoots that underwent two, four, six, eight, or ten cycles of in vitro subculturing by random amplified polymorphic DNA (RAPD) analysis. When applied to the micropropagation of mature shoot tips
of T. longicaulis C. Presl subsp. longicaulis var. subisophyllus (Borbás) Jalas, the optimized in vitro propagation protocol resulted in a 97.5% shoot regeneration rate, with five shoots formed per explant, and 100% rooting.
Rooted plantlets of both species were transferred to 250-mL plastic pots and successfully acclimatized by gradually reducing
the relative humidity. 相似文献
12.
Summary A micropropagation procedure for the adult cherimoya tree (Annona cherimola Mill.) is described. Axillary shoot proliferation was obtained after culturing nodal sections from Annona cherimola cv. ‘Fino de Jete’, on Murashige and Skoog (MS) medium supplemented with 2.28 μM zeatin. Roots were induced after preincubation of shoots for 3d in light on MS basal medium supplemented with lgl−1 activated charcoal, followed by culturing for 10 d (7 d dark and 3 d light) on MS medium with 492 μM indole-3-butyrie acid (IBA), 15 gl−1 sucrose, and 200 mgl−1 citric acid. Sixty-eight percent of induced shoots rooted after transferring to the same medium without auxin and with the
macroelements at half strength and the sucrose at 20gl−1. About 65% of rooted shoots survived after acclimatization. The procedures described herein may prove useful for clonal micropropagation
of selected genotypes of cherimoya. 相似文献
13.
In the present study, in vitro regeneration system for a recalcitrant woody tree legume, Leucaena leucocephala (cvs. K-8, K-29, K-68 and K-850) from mature tree derived nodal explants as well as seedling derived cotyledonary node explants
was developed. Best shoot initiation and elongation was found on full-strength Murashige and Skoog (MS) medium supplemented
with 3 % (m/v) sucrose, 100 mg dm−3 myoinositol, 100 mg dm−3 glutamine, 20.9 μM N
6-benzylamino-purine (BAP) and 5.37 μM 1-naphthalene acetic acid (NAA). Rooting was induced in half-strength MS medium containing
2 % (m/v) sucrose, 100 mg dm−3 myoinositol, 14.76 μM indole-3-butyric acid (IBA) and 0.23 μM kinetin. The cultivar K-29 gave the best response under in vitro conditions. Rooted plantlets were subjected to hardening and successfully transferred to greenhouse. Further, somatic embryogenesis
from nodal explants of cv. K-29 via an intermittent callus phase was also established. Pronounced callusing was observed on full-strength MS medium containing
3 % (m/v) sucrose, 100 mg dm−3 myoinositol, 40.28 μM NAA and 12.24 μM BAP. These calli were transferred to induction medium and maximum number of globular
shaped somatic embryos was achieved in full-strength MS medium fortified with 3 % (m/v) sucrose, 100 mg dm−3 myoinositol, 15.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D), 5.0 μM BAP and 1.0 mM proline. Moreover, an increase in endogenous
proline content up to 28th day of culture in induction medium was observed. These globular shaped somatic embryos matured in full-strength MS medium
with 3 % (m/v) sucrose, 100 mg dm−3 myoinositol, 10.0 μM BAP, 2.5 to 5.0 μM IBA and 0.5 mM spermidine. 相似文献
14.
Direct shoot regeneration was achieved from immature inflorescence explants of Chlorophytum arundinaceum and C. borivilianum on half-strength Murashige & Skoog (MS) medium supplemented with 3.0 mg L−1 BA, 150 mg L−1 Ads, 0.1 mg L−1 NAA and 3% (w/v) sucrose under a 16-h photoperiod. The shoot buds developed within 2–3 weeks of culture. High frequency of
shoot bud regeneration was achieved when cultured on similar medium in subsequent subcultures. The apex portion (Type I) of
the inflorescence produced more shoot buds as compared to the middle ones (type II). More than 75% of the terminal segment
explants produced shoot buds within 4-week of culture. Response of basal portion (Type III) was negative for shoot bud initiation.
Shoots rooted on half-strength basal MS medium supplemented with half-strength MS medium, 0.1 mg L−1 IAA and 2% (w/v) sucrose. Micropropagated plantlets were hardened in the green house and successfully established in the
soil where 90% of the plants survived. This protocol would be useful for commercial micropropagation and genetic improvement
prograrmme. 相似文献
15.
Summary An efficient in vitro plant regeneration system from cotyledons was established in tetraploid Isatis indigotica Fort. Factors influencing shoot regeneration from cotyledons, including culture medium type, combinations of plant growth
regulators, and sucrose concentrations in the medium, as well as illumination were investigated. Murashige and Skoog's (MS)
medium was found to be best for promoting shoot regeneration, followed by Gamborg's B5 and White's medium. The highest shoot regeneration frequency was achieved from cotyledons cultured on MS medium supplemented
with 2.0 mgl−1 (8.9 μM) 6-benzyladenine and 1.0 mgl−1 (5.4 μM) α-naphthaleneacetic acid (NAA), with 97.9% regeneration, associated with a high number of multiple shoots developed per
explant (8.6 shoots per explant). A sucrose concentration of 3% present in the medium and light conditions were beneficial
for shoot regeneration. The shoots developed were rooted in a half-strength MS medium supplemented with 1.0 mgl−1 (5.4 μM) NAA and successfully transplanted in soil in pots with over 85% survival. The establishment of an efficient plant regeneration
procedure from cotyledons provides a basis for the rapid in vitro multiplication of tetraploid Isatis indigotica Fort., one of the most extensively used medicinal plants in China currently under great shortage. 相似文献
16.
T. Zhang 《In vitro cellular & developmental biology. Plant》2007,43(2):91-94
This study investigated the factors affecting in vitro flowering of Perilla frutescens. The shoots regenerated from cotyledonary and hypocotyl explants cultured on Murashige and Skoog (MS) medium supplemented
with benzyladenine (BA) and indole-3-acetic acid, each at 0.5 mg l−1, were excised and transferred to MS medium containing 30 g l−1 of sucrose, 8.25 g l−1 of ammonium nitrate, and 1.0 mg l−1 of BA. After 40 d of culture, 86.2% of shoots flowered and most of which self-fertilized in vitro and produced mature fruits with viable seeds. These seeds were germinated and plants were grown to maturity and flowered
in soil under greenhouse conditions. The in vitro flowering system reported in this study may facilitate rapid breeding of P. frutescens and offers a model system for studying the physiological mechanism of flowering. 相似文献
17.
Guirong Qiao Jing Zhou Jing Jiang Yuehua Sun Luanyin Pan Honggai Song Jingmin Jiang Renying Zhuo Xiaojuan Wang Zongxiu Sun 《Plant Cell, Tissue and Organ Culture》2010,102(2):163-170
Malaxis acuminata is a terrestrial orchid that grows in shady areas of semi-evergreen to shrubby forests. It is highly valued for its medicinal
properties as dried pseudo-bulbs are important ingredients of several Ayurvedic preparations. In this study, adventitious
shoot buds were induced from internodal explants of M. acuminata grown on Murashige and Skoog (MS) medium supplemented with different concentrations of 6-benzyladenine (BA), kinetin (Kn),
and thidiazuron (TDZ). Of the three cytokinins used, TDZ at 3 mg l−1 induced the highest frequency (82%) of organogenic explants. However, all responding explants produced only a single adventitious
shoot irrespective of the type and concentration of the cytokinin. Adding 0.5 mg l−1 α naphthaleneacetic acid (NAA) to the medium enhanced adventitious shoot formation. In the presence of 3 mg l−1 TDZ and 0.5 mg l−1 NAA, frequency of organogenesis was 96% with a mean number of 6.1 shoots per explant. Prolonged culture or subculture on
the same medium did not promote further shoot production. However, transfer of these cultures to MS medium supplemented with
3 mg l−1 TDZ and 0.5 mg l−1 NAA and various concentrations of different polyamines (PAs), including spermine, spermidine, and putrescine, significantly
increased mean shoot number per explant. The highest frequency of shoot induction (100%) and mean shoot number per explant
(14.6) was observed on MS medium with 3 mg l−1 TDZ, 0.5 mg l−1 NAA, and 0.4 mM spermidine. Regenerated shoots were excised and subcultured on an elongation medium consisting of MS medium
with 3 mg l−1 BA. Moreover, the highest frequency of rooting (96%) and mean number of roots per shoot (3.3) was observed on MS medium with
4 mg l−1 indole-3-butyric acid (IBA) and 1.5 mg l−1 activated charcoal (AC). Almost 90% of rooted shoots were successfully acclimatized and established ex vitro. 相似文献
18.
Summary An efficient in vitro propagation system was developed for Arnebia euchroma, an important Chinese traditional medicinal plant. The present study utilized thidiazuron (TDZ) for the induction of shoot
organogenesis on cotyledon and hypocotyl explants. The maximal number of shoots was obtained on the modified Linsmaier and
Skoog (LS) medium supplemented with 1.0 mgl−1 (4.5 μM) TDZ for 12d on cotyledon explants (8.6 shoots per cotyledon explant). Other cytokinins (kinetin and 6-benzyladenine) and
auxin (α-naphthaleneacetic acid) were not efficient in inducing regeneration on cotyledon explants. Browning of the basal
portion of the subcultured shoots could be significantly reduced when they were cultured on the modified LS medium supplemented
with 100 mgl−1 (33.3 μM) polyvinylpyrrolidone. Well-developed shoots formed roots on the same medium containing 1.0 mgl−1 (4.9 μM) indole-3-butyric acid. The efficient regeneration protocol reported here provides an important means of micropropagation
of this plant. Furthermore, this protocol is essential to future genetic improvement of plants via transformation protocols. 相似文献
19.
The present paper reports a protocol for minimum growth conservation of Drosophyllum lusitanicum (L.) Link. in vitro. Double-node cuttings were maintained for 4, 8 and 12 months at 5 or 25 °C in the dark. The effects of sucrose either alone
at 5, 20, 30, 40 and 60 g dm−3 or at 20, 40 and 60 g dm−3 in combination with 20 g dm−3 mannitol, on survival and post-storage shoot multiplication efficiency were investigated. The cultures could effectively
be conserved under minimum growth at 5 °C for 8 months on Murashige and Skoog’s medium supplemented with 60 g dm−3 sucrose, 20 g dm−3 mannitol and 0.91 μM zeatin. Following extended conservation, the cultures could be successfully regenerated into new shoots,
and they were morphologically similar to those of non-stored controls. 相似文献
20.
Breeding linseed (Linum usitatissimum L.) using haploid techniques allows breeders to develop new cultivars in a shorter time period. Many research groups successfully
created new linseed genotypes through anther culture; however ovary culture has been the subject of only a few earlier studies.
In the present study, the effect of genotype and growth regulators combination on callus induction and shoots regeneration
in ovary culture of nine commercially important linseed cultivars was investigated. Ovaries were cultured on modified MS medium
supplemented with three different combinations of plant growth regulators. Variable callogenic responses were expressed by
all of the genotypes tested on different induction media. The results suggested that specific combination of growth regulators
for callus induction must be designed for each genotype. Shoot regeneration from ovary derived callus is a critical phase
of the whole gynogenetic process. Differences in adventitious shoot formation frequency among genotypes were demonstrated
and four responsive genotypes have been selected. Ovary derived callus from cultivar ‘Mikael’ manifested the highest adventitious
shoot formation frequency with a high number of shoots per explant. The optimum ratio of growth regulators for shoot regeneration
was shown to depend on the genotype. Cultivars ‘Linola’, ‘Mikael’ and ‘Szaphir’ showed the highest shoot regeneration frequency
when callus had originated on induction medium supplemented with 2 mg L−1 BAP and 2 mg L−1 NAA, while combination of 1 mg L−1 BAP and 2 mg L−1 IAA promoted shoot formation in ovary-derived callus of ‘Barbara’. The highest rate of shoots per explant has been obtained
in second subculture. 相似文献