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1.
An alga known as “Nannochloropsis”, isolated from a prawn farm in Hainan, China, has been critically investigated and identified as Chlorella, a member of the Chlorophyceae based on fatty acid composition, ultrastructure, and 18S rDNA. Cells of this alga were spherical,
measured by 1–6 μm in diameter and were enclosed in thin walls of approximately 0.04 μm thickness. They contained several
small mitochondria, two to three thylakoids and had no vacuoles. There were many pyrenoids in the algal cells and their thylakoid
lamellae were sparse and not translucent. Many lipid droplets were present in the cytoplasm. The total lipid content of this
alga was 3% per gram dry weight and its major fatty acids were C16:0, C18:0, C18:1, C18:2, C18:3 and C20:0. Eicosapentaenoic acid (C20:5, EPA) was not detected. The length of its 18S rDNA sequence was 1,712 bp. 18S rDNA sequence analyses indicated that this
alga was a species of Chlorella. 相似文献
2.
Summary L cells were grown in spinner cultures in a defined medium consisting of Waymouth medium MB752/1 (19) supplemented with 2
mg of fatty acid-free bovine serum albumin (BSA) per ml and 5 μg of oleate per ml (WO5 medium). Growth in WO5 medium was comparable to spinner L cell growth in two serum-containing media. The optimal concentration of oleate in the
WO medium was 5 to 10 μg per ml. The use of 20 to 80 μg of oleate per ml of medium resulted in lower peak populations and
earlier declines in viable cell counts. Cell death occurred rapidly in WO160 medium. Cell growth in WO medium containing 5 to 80 μg of oleate per ml was well above the level of growth observed when
no oleate was present in the medium. Since the total lipid and fatty acid compositions of the BSA used in this study have
been characterized by the authors, the WO medium may be considered a defined medium. L cells have been continuously maintained
in spinner cultures in WO5 medium for over 50 passages with no major variation in the growth pattern. A 1000-fold increase inChlamydia psittaci strain meningopneumonitis, with a peak titer of 9.3×107 plaque-forming units per ml, was observed when the chlamydial agents were grown in spinner L cells in WO5 medium.
This investigation was supported by Public Health Service Research Grant HE 08214 from the Program Projects Branch, Extramural
Programs, National Heart and Lung Institute; The World Health Organization; and The Hormel Foundation. 相似文献
3.
Olesya A. Kharenko L. Irina Zaharia Michael Giblin Vera Čekić David C. Taylor C. Don Palmer Suzanne R. Abrams Michele C. Loewen 《Plant Cell, Tissue and Organ Culture》2011,105(3):415-422
Lesquerella fendleri (commonly known as “Fendler’s bladderpod” or “yellowtop”) is a member of the Brassicaceae and is an important seed oil-producing
plant. The lipid profile of L. fendleri seed indicates potential for producing a high quality replacement for castor oil. In this work, characterization of the lipid
content of a suspension cell culture, derived from seedlings of L.
fendleri, is provided. Under the described suspension cell culture conditions, 16:0, 18:1Δ9, 18:2 Δ9, Δ12 and 18:3 Δ9, Δ12, Δ15 fatty
acids were found to accumulate in the cells, while 16:0, 26:0 and 28:0 fatty acids were predominant in the culture medium.
Subsequently, the effect of application of abscisic acid (ABA), which modulates lipid accumulation, was assessed. Exogenously
applied ABA was taken up by the cells and metabolized via the conjugation pathway, resulting in the accumulation of ABA-glucose
ester. Preliminary tests demonstrate the cell line is responsive to exogenous ABA, resulting in increased cellular lipid content
and increased accumulation of lipids in the culture medium. This novel L. fendleri suspension culture presents a valuable model system for efficient characterization of mechanisms associated with ABA-induced
accumulation of lipids. 相似文献
4.
Summary High-frequency somatic embryogenesis and plant regeneration was achieved on callus derived from leaf (petiole and lamina)
and internode explants of Centella asiatica L. Growth regulators significantly influenced the frequency of somatic embryogenesis and plant regeneration. Calluses developed
on Murashige and Skoog (MS) medium fortified with 4.52 μM 2,4-dichlorophenoxyacetic acid (2,4-D) or 5.37 μM α-naphthaleneacetic acid (NAA), both with 2.32 μM kinetin (Kn), were superior for somatic embryogenesis. Callus developed on NAA and Kn-supplemented medium favored induction
and maturation of embryos earlier compared to that on 2,4-D and Kn. Embryogenic callus transferred from NAA and Kn-supplemented
medium to suspension cultures of half-strength MS medium with NAA (2.69 μM) and Kn (1.16 μM) developed a mean of 204.3 somatic embryos per 100 mg of callus. Embryogenic callus transferred from 2,4-D and Kn subsequently
to suspension cultures of half-strength MS medium with 2,4-D (0.45 μM) and Kn (1.16 μM) developed a mean of 303.1 embryos per 100 mg of callus. Eighty-eight percent of the embryos underwent maturation and conversion
to plantlets upon transfer to half-strength MS semisolid medium having 0.054 μM NAA with either 0.044 μM BA or 0.046 μM Kn. Embryo-derived plantlets established in field conditions displayed morphological characters identical to those of the
parent plant. 相似文献
5.
A cryptic intracellular green alga in <Emphasis Type="Italic">Ginkgo biloba</Emphasis>: ribosomal DNA markers reveal worldwide distribution 总被引:1,自引:0,他引:1
Intracellular symbioses involving eukaryotic microalgae and a variety of heterotrophic protists and invertebrates are widespread,
but are unknown in higher plants. Recently, we reported the isolation and molecular identification of a Coccomyxa-like green alga from in vitro cell cultures of Ginkgo biloba L. This alga resides intracellularly in an immature “precursor” form with a nonfunctional chloroplast, implying that algal
photosynthetic activity has no role in this endosymbiosis. In necrotizing Ginkgo cells, precursors evolved into mature algae, proliferated, and were liberated into the culture medium after host cell bursting.
In the present paper we demonstrate by molecular methods a worldwide distribution of the alga in planta. Endosymbiont-specific
sequences of ribosomal DNA could be traced in Ginkgo tissues of each specimen examined from different geographic locations in Europe, North America, and Asia. The Ginkgo/Coccomyca association represents a new kind of intracellular, vertically inherited symbiosis. Storage bodies, probably of lipid nature,
present in the cytoplasm of each partner suggest a possible involvement of the endosymbiont in metabolic pathways of its host. 相似文献
6.
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
7.
Summary Multiple shoots were induced from cotyledonary nodes of grasspea (Lathyrus sativus L.) derived from 7-d-old in vitro seedlings on Murashige and Skoog (MS) medium containing N6-benzyladenine (BA), kinetin, or thidiazuron, BA being the most effective. Among the five genotypes tested, shoot proliferation
frequency was the highest (93.3%) for IC-120487, giving the maximum number of shoots (11.3 shoots per explant) on MS medium
augmented with 2.0 mgl−1 (8.87 μM) BA. Shoot cultures were established by repeatedly subculturing the original cotyledonary nodes on fresh medium after each
harvest of the newly formed shoots. Thus 30–40 shoots were obtained in 2 mo. from a single cotyledonary node. Up to 81.8%
of the shoots developed roots following transfer to half-strength MS medium containing 0.5 mgl−1 (2.85 μM) indole-3-acetic acid. Plantlets were successfully acclimatized and established in soil. 相似文献
8.
Shashi Kant Singh Manoj K. Rai Pooja Asthana L. Sahoo 《Acta Physiologiae Plantarum》2009,31(4):693-698
An efficient and improved in vitro propagation system for Spilanthes acmella L. using transverse thin cell layer (tTCL) culture system was established. The frequency of shoot regeneration from tTCL
nodal segments was affected by concentrations of plant growth regulators and orientation of the explant. MS (Murashige and
Skoog in Physiol Plant 15:473–497, 1962) medium with 5.0 mg dm−3 BAP was optimal for shoot regeneration. Upon this medium, the explant inoculated in the upright orientation exhibited a high
frequency of shoot regeneration (about 97%), and the highest number of shoots (31.5) per explant. The intact node (1.0–1.5 cm)
cultured on the same medium had significantly lower shoot multiplication ability with only 4.5 shoots per responsive explant.
As compared to BAP alone, the combination of BAP and Kin or NAA did not have positive effects on shoot multiplication from
tTCL nodal segments. Rooting of shoots was achieved on growth regulator free full-strength MS medium. Plantlets were transplanted
into soil with 90–100% survival rate. 相似文献
9.
Altered lipid composition and enhanced lipid production in green microalga by introduction of brassica diacylglycerol acyltransferase 2
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Irshad Ahmad Anil K. Sharma Henry Daniell Shashi Kumar 《Plant biotechnology journal》2015,13(4):540-550
Higher lipid biosynthesis and accumulation are important to achieve economic viability of biofuel production via microalgae. To enhance lipid content, Chlamydomonas reinhardtii was genetically engineered with a key enzyme diacylglycerol acyltransferase (BnDGAT2) from Brassica napus, responsible for neutral lipid biosynthesis. The transformed colonies harbouring aph7 gene, screened on hygromycin‐supplemented medium, achieved transformation frequency of ~120 ± 10 colonies/1 × 106 cells. Transgene integration and expression were confirmed by PCR, Southern blots, staining lipid droplets, proteins and spectro‐fluorometric analysis of Nile red‐stained cells. The neutral lipid is a major class (over 80% of total lipids) and most significant requirement for biodiesel production; this was remarkably higher in the transformed alga than the untransformed control. The levels of saturated fatty acids in the transformed alga decreased to about 7% while unsaturated fatty acids increased proportionately when compared to wild type cells. Polyunsaturated fatty acids, especially α‐linolenic acid, an essential omega‐3 fatty acid, were enhanced up to 12% in the transformed line. Nile red staining confirmed formation of a large number of lipid globules in the transformed alga. Evaluation of long‐term stability and vitality of the transgenic alga revealed that cryopreservation produced significantly higher quantity of lipid than those maintained continuously over 128 generations on solid medium. The overexpression of BnDGAT2 significantly altered the fatty acids profile in the transformed alga. Results of this study offer a valuable strategy of genetic manipulation for enhancing polyunsaturated fatty acids and neutral lipids for biofuel production in algae. 相似文献
10.
Gang-Guk Choi Byung-Hyuk Kim Chi-Yong Ahn Hee-Mock Oh 《Journal of applied phycology》2011,23(6):1031-1037
The influence of nitrogen (N) deficiency on the cell growth and intracellular lipid production of the alga Botryococcus braunii UTEX 572 was investigated. Biomass concentration and lipid content of B. braunii cultivated in modified Chu-13 medium containing 0.04, 0.37, and 3.66 mM nitrate were 0.23–0.38 g L−1 and 36–63% of dry cell weight, respectively. The specific growth rate of B. braunii reached a constant of 0.185 day−1 during cultivation with an initial nitrate feed of 3.66 mM. The maximum lipid content of B. braunii was 63% with 0.04 mM nitrate. However, the maximum lipid productivity of 0.019 g L−1 day−1 was achieved with 0.37 mM nitrate. The level of oleic acid, an important component of biodiesel, was higher at 86% of the
total fatty acids under N-limited conditions (0.04 mM nitrate) compared to 69% under N-sufficient conditions (3.66 mM nitrate).
Furthermore, expression of the stearoyl-ACP desaturase gene (sad) encoding a stearoyl-ACP desaturase involved in the synthesis of oleic acid was 2.6-fold higher under N-limited conditions
than under N-sufficient conditions. 相似文献
11.
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
12.
The genome of Lactococcus lactis encodes a single long chain 3-ketoacyl-acyl carrier protein synthase. This is in contrast to its close relative, Enterococcus faecalis, and to Escherichia coli, both of which have two such enzymes. In E. faecalis and E. coli, one of the two long chain synthases (FabO and FabB, respectively) has a role in unsaturated fatty acid synthesis that cannot
be satisfied by FabF, the other long chain synthase. Since L. lactis has only a single long chain 3-ketoacyl-acyl carrier protein synthase (annotated as FabF), it seemed likely that this enzyme
must function both in unsaturated fatty acid synthesis and in elongation of short chain acyl carrier protein substrates to
the C18 fatty acids found in the cellular phospholipids. We report that this is the case. Expression of L. lactis FabF can functionally replace both FabB and FabF in E. coli, although it does not restore thermal regulation of phospholipid fatty acid composition to E. coli
fabF mutant strains. The lack of thermal regulation was predictable because wild-type L. lactis was found not to show any significant change in fatty acid composition with growth temperature. We also report that overproduction
of L. lactis FabF allows growth of an L. lactis mutant strain that lacks the FabH short chain 3-ketoacyl-acyl carrier protein synthase. The strain tested was a derivative
(called the ∆fabH bypass strain) of the original fabH deletion strain that had acquired the ability to grow when supplemented with octanoate. Upon introduction of a FabF overexpression
plasmid into this strain, growth proceeded normally in the absence of fatty acid supplementation. Moreover, this strain had
a normal rate of fatty acid synthesis and a normal fatty acid composition. Both the ∆fabH bypass strain that overproduced FabF and the wild type strain incorporated much less exogenous octanoate into long chain
phospholipid fatty acids than did the ∆fabH bypass strain. Incorporation of octanoate and decanoate labeled with deuterium showed that these acids were incorporated
intact as the distal methyl and methylene groups of the long chain fatty acids. 相似文献
13.
Summary Protoplasts were isolated from Agrobacterium rhizogenes A4-transformed cell line of Medicago sativa L. The highest yield of protoplasts (4.2×106 per g fresh weight) was obtained from 12-d-old calluses after being subeultured on fresh medium. The viability of protoplasts
reached over 80%. Protoplasts were induced to undergo sustained divisions when cultured in Durand et al. (DPD) medium supplemented
with 2 mgl−1 (9.05 μM) 2,4-dichlorophenoxyacetic acid, 0,2mgl−1 (0.93 μM) kinetin, 0.3 M mannitol, 2% (w/v) sucrose, and 500 mgl−1 casein hydrolyzate at a plating density of 1.0×105 per ml. An agarose-beads culture method was appropriate for protoplast division of transformed alfalfa. The division frequency
was about 30%. Numerous hairy roots were induced from protocalluses on Murashige and Skoog medium without growth regulators.
Paper electrophoresis revealed that all of the regenerated hairy roots tested synthesized the corresponding opines. This protoplast
culture system would be valuable for further somatic hybridization in forage legumes. 相似文献
14.
The ability was determined of the rumen ciliate Eudiplodinium maggii to utilize chitin from fungal cell wall. Cultivation experiments shoved that the population concentration (number of ciliates
in vitro) was positively correlated with chitin doses. Cell extract prepared from the bacteria-free ciliates degraded colloidal chitin
releasing 2.0 μmol reducing sugar per mg protein per h. End products of this reaction were chitotriose and N-acetylglucosamine. Incubation of the bacteria-free ciliates with chitin resulted in an increase in the concentration of acetic,
propionic and butyric acids in the incubation medium. The production rate of total volatile fatty acids (VFA) by ciliates
incubated with and without chitin was 45.0 and 30.5 pmol VFA per protozoan, respectively, the molar proportion of particular
acids remaining unchanged. 相似文献
15.
A rapid and efficient micropropagation system was developed for Psoralea corylifolia, an endangered, valuable medicinal plant. Multiple shoot buds were obtained in half-strength liquid Phillips–Collins (L2)
medium supplemented with 5 μM benzylaminopurine (BA) and 5 μM thidiazuron (TDZ) from apical bud explants of 1-week-old cultures.
The shoot buds were subcultured on enriched solid L2 medium supplemented with different concentrations and combinations of
BA, kinetin (KIN), 2-isopentenyladenine (2iP), TDZ, bavistin (BVN) and trimethoprim (TMP). Enriched solid L2 medium supplemented
with 2 μM BA, 1 μM TDZ and 100 mg l−1 BVN were more effective in producing greater number of shoots per explant (85.2 ± 0.9 shoots/explant) after 4 weeks of culture.
The regenerated shoots (40–50 mm in length) rooted and accompanied by hardening upon transfer to 50 μM indole-3-butyric acid
(IBA) for 15 min and followed by planting in sterile soil mixture and vermiculate (3:1 v/v), with 50 ml of one-eight strength
L2 basal salt solution devoid of sucrose and inositol, supplemented with 5 μM IBA and 100 mg l−1 BVN. The plants achieved 100% rooting with hardening. Subsequently the rooted plants were successfully established in the
field. The survival percentage differed with seasonal variations. The concentration of psoralen was evaluated in different
tissues of ex vitro and in vivo grown plants by high-performance liquid chromatography (HPLC). Psoralen content was increased
in leaves (2.97%), roots (2.38%), stems (5.40%) and seeds (1.63%) of ex vitro plants than the in vivo plants. This system
facilitates for commercial and rapid propagation of P. corylifolia for conservation strategies and phytomedicine production. 相似文献
16.
Maggie Panaia Eric Bunn Jen McComb 《In vitro cellular & developmental biology. Plant》2011,47(3):379-386
Somatic embryogenesis was developed as a method of mass propagation for Lepidosperma drummondii (Cyperaceae), a difficult to propagate but important species for post-mining restoration in a region of high plant biodiversity,
in the southwest of Western Australia. Cultures were initiated from excised zygotic embryos, shoot cultures to rhizomes. Only
zygotic embryos of L. drummondii developed somatic embryos, with half strength Murashige and Skoog basal medium (BM) and 1 μM 2,4-dichlorophenoxyacetic acid
(2,4-D) being the most effective combination. The first culture cycle yielded a mean of 30 somatic embryos per excised zygotic
embryo forming an embryo cluster. After a further 6 wk in culture (on fresh BM with 1 μM 2,4-D), approximately 350 somatic
embryos per starting embryo cluster were recorded. Following regular sub-culturing of primary somatic embryo clusters onto
fresh media (every 4 wk), more than 74,000 secondary somatic embryos were estimated to have been produced after eight subculture
periods. This translates to between 1,000 and 2,000 somatic embryos produced from an estimated 45 mg of starting tissue per
culture plate or potentially 22,0000–44,000 somatic embryos per gram of tissue. This is a significant improvement over all
previous methods used to propagate L. drummondii, in which typical in vitro shoot multiplication rates are as low as 1.43 per 8 wk. This also compared favourably with published data and concurrent
experiments undertaken in this study (as an extra control measure) on somatic embryo production for a related species Baloskion tetraphyllum (using the same BM with 1 μM 2,4-D and coleoptile segments as explants). Various media combinations were investigated for
efficacy in converting somatic embryos into plants with best results ranging from 86% to 100% conversion for B. tetraphyllum on BM without plant growth regulators. Development of L. drummondii somatic embryos into plants was not observed on BM without plant growth regulators. However, a best result of 39% conversion
to plants was observed on BM with 1 μM thidiazuron. This is the first report of successful development of somatic embryogenesis
and conversion of somatic embryos into plants using thidiazuron for the Australian cyperale L. drummondii. 相似文献
17.
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
18.
Summary Somatic embryo (bipolar) or shoot (monopolar) morphogenesis in mesophyll cells of Euphorbia nivulia Buch.-Ham in vitro was dependent on the type of auxin supplementing Murashige and Skoog (MS) medium containing benzyladenine. Direct in vitro morphogenesis, i.e., organogenesis, and somatic embryogenesis were significantly influenced by seasonal growth of the donor
plant, explant position (proximal, mid, and distal), and light. Explants collected in march/April were superior to July/August
material. Proximal explants underwent morphogenesis more readily than mid- and tip-derived explants. Incubation in the light
favored morphogenesis while darkness was inhibitory. Kinetin (Kn) was also inhibitory to morphogenesis. MS medium enriched
with different levels of N6-benzyladenine (BA) alone, or in combination with α-naphthaleneacetic acid (NAA) or indole-3-acetic acid (IAA), induced adventitious
shoots directly. Explants collected in March/April cultured on medium with 13.3 μM BA and 2.69 μM NAA developed the highest number of shoots, a mean of 15.2 shoots per proximal explant. Developed shoots rooted the best
on half-strength MS medium with 2.46 μM indole-3-butyric acid, which developed a mean of 5.2 roots per shoot. Rooted healthy shoots could be transplanted to small
pots, with an 80% survival rate. Addition of 2,4-dichlorophenoxyacetic acid (2.4-D) to BA-supplemented medium was obligatory
to develop somatic embryos. MS medium containing 2.26 μM 2,4-D and 4.44 μM BA induced a mean of 44.8 somatic embryos per proximal explant. The embryos passed through distinct stages of embryogenesis,
namely globular, heart, torpedo, and early cotyledonary. The embryos (88%) underwent maturation on half-strength MS medium
with 2.89 μM gibberellic acid (GA3), and its subsequent transfer on half-strength MS basal medium in light conditions facilitated 80% conversion of embryos
to plantlets. Direct shoots or embryos were originated from the mesophyll cells. Somatic embryo development was concurrent
with the independent origin of vasculature in the bulbous basal portion. The survival rate of embryo-derived plants was 90%. 相似文献
19.
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
20.
Summary Carbohydrate type and concentration and their interactive effects on in vitro shoot proliferation of three lingonberry (Vaccinium vitis-idaea ssp. vitis-idaea L.) cultivars (‘Regal’, ‘Splendor’, and ‘Erntedank’) and two V. vitis-idaea ssp. minus (Lodd) clones (‘NL1’ and ‘NL2’) were studied. Nodal explants were grown in vitro on medium with 2 μM zeatin and either glucose, sorbitol, or sucrose at a concentration of 0, 10, 20, or 30 gl−1. The interactive effects of carbohydrate type and concentration and genotype were important for shoot proliferation. The
best response was afforded by sucrose at 20 gl−1 both in terms of explant response and shoot developing potential, although glucose supported shoot growth equally well, and
in ‘NL1’ at 10 gl−1 it resulted in better in vitro growth than sucrose. Carbohydrate concentration had little effect on shoot vigor. The genotypes differed in terms of shoots
per explant, length, and vigor, leaves per shoot, and callus formation at the base of explants; this was manifested with various
types and concentrations of carbohydrate. Changing the positioning of explants on the medium from vertically upright to horizontal
increased the shoot and callus size, but decreased shoot height and leaves per shoot. Proliferated shoots were rooted on a
peat:perlite (1∶1, v/v) medium and the plantlets were acclimatized and eventually established in the greenhouse. 相似文献