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1.
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
2.
Carimi Francesco Tortorici Maria Concetta De Pasquale Fabio Crescimanno Francesco Giulio 《Plant Cell, Tissue and Organ Culture》1998,54(3):183-189
Somatic embryogenesis was induced and plant regeneration was obtained in 11 different genotypes of sweet orange navel group
[Citrus sinensis (L.) Osb.] from cultures of stigma/style explants and undeveloped ovules. Explants were cultured on 3 different
modifications of Murashige and Skoog medium: 500 mg l-1 malt extract; 500 mg l-1 malt extract and 4.6 μM kinetin; and 500
mg l-1 malt extract and 13.3 μM 6-benzylaminopurine. Sucrose (146 mM) was used as carbon source. Somatic embryogenesis occurred
1–3 months after culture initiation from undeveloped ovule and stigma/style cultures of all the genotypes tested. Somatic
embryos developed into plantlets with a high frequency (74%) after transfer to Murashige and Skoog medium supplemented with
146 mM sucrose and 500 mg l-1 malt extract. Plants were successfully transferred to soil.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
High yield production of salidroside in the suspension culture of Rhodiola sachalinensis 总被引:6,自引:0,他引:6
Salidroside has been identified as the most potent ingredient of the Chinese medicine herb, Rhodiola sachalinensis. Since the natural supply of this herb is rapidly decreasing, we established a compact callus aggregate (CCA) strain and culturing system for high yield salidroside production. Several callus strains induced from the explants originated from root, stem, leaf and cotyledon of R. sachalinensis were established and screened for rapid growth rate, high salidroside content and easy propagation in suspension culture condition. The CCA strain was established from a callus strain initiated from the cotyledon. The kinetics of dry weight accumulation and cellular salidroside content in various culture conditions for the strain was determined. For high salidroside production, the optimal inoculum amount was 10% and the optimal concentration for 6-benzylaminopurine and indole-3-butyric acid added in the liquid medium was 5 and 2.5 mg l-1, respectively. The acidic culture medium and a faster shaking speed favored the salidroside accumulation. The addition of 2,4-D, in the liquid MS medium and the utilization of L-tyrosol for chemical feeding enhanced salidroside production. Using a proper combination of culture condition and treatment, salidroside accumulation could reach 57.72 mg g-1 dry weight, that was 5-10-fold higher than that detected in field-grown plants. The corresponding salidroside yield was 555.13 mg l-1, a level suitable for cost effective commercial production to compensate the natural resource shortage of R. sachalinensis. 相似文献
4.
Fish kills of milkfish Chanos chanos and tilapia Oreochromis spp. now occur frequently in brackish, marine, and freshwater
farms (ponds, pens, and cages) in the Philippines. Aquafarms with high organic load, limited water exchange and circulation,
no aeration, and high stocking and feeding rates can become oxygen-depleted and allow sulfide from the sediments to appear
in the water column and poison free-swimming fish. The sulfide tolerance of 2–5 g milkfish and 5–8 g O. mossambicus was determined
in 25-liter aquaria with flow-through sea water (100 ml min-1) at 26–30 °C and sulfide stock solutions pumped in at 1ml min-1.
Total sulfide concentrations in the aquaria were measured by the methylene blue method and used in the regression against
the probits of % survival. Four experiments showed that the two species have similar sulfide tolerance. In sea water of pH
8–8.5, about 163 ± 68 μM or 5.2 ± 2.2 mg l-1 total sulfide (mean ± 2 se) or 10 μM or 313 μg l-1 H2S was lethal to 50% of the
fish in 4–8 h, and 61 ± 3 μM total sulfide or 4 μM H2S in 24–96 h (to convert all sulfide concentrations: 1 μM = 32 μg l-1).
Earthen pond bottoms had 0–382 μM total dissolved sulfide (mean ± sd = 54 ± 79 μM, n = 76); a tenth of the samples had >200
μM. The water column may have such sulfide levels under hypoxic or anoxic conditions. To simulate some of the conditions during
fish kills, 5–12 g milkfish were exposed to an abrupt increase in sulfide, alone or in combination with progressive respiratory
hypoxia and decreasing pH. The tests were done in the same flow-through set-up but with sulfide pumped in at 25 ml min-1.
The lethal concentration for 50% of the fish was 197 μM total sulfide or 12 μM H2S at 2 h, but 28–53 μM sulfide allowed fish
to survive 6–10 h. Milkfish in aquaria with no aeration nor flow-through sea water died of respiratory hypoxia in 5–8 h when
oxygen dropped from 6 to 1 mg l-1. Under respiratory hypoxia with 30–115 μM sulfide, the fish died in 2.5–4 h. Tests with
low pH were done by pumping a weak sulfuric acid solution at 25 ml min-1 into aquaria with flow-through sea water such that
the pH dropped from 8 to 4 in 5 h. Under these conditions, milkfish died in 7–9 h when the pH was 3.5. When 30–93 μM sulfide
was pumped in with the acid, the fish died in 2–6 h when the pH was still 4.5–6.3. Thus, sulfide, hypoxia, and low pH are
each toxic to milkfish at particular levels and aggravate each other's toxicity. Aquafarms must be well oxygenated to prevent
sulfide toxicity and fish kills.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
G. G Ning S. P Bai M. Z Bao L. Liu 《In vitro cellular & developmental biology. Plant》2007,43(2):95-100
Using immature embryos and cotyledons as explants, a successful system to culture immature embryos and induce direct regeneration
from cotyledons was established for Prunus mume “Xuemei”. For immature embryo culture, a high frequency of plantlet formation (89.5%) from the embryonic axis was obtained
using half-strength Murashige and Skoog (1/2 MS) medium supplemented with 13.2 μM 6-benzyladenine (BA) and 2.7 μM 1-naphthaleneacetic
(NAA). Shoots formed directly from cotyledons with the embryo axis intact when explants were cultured on 1/2 MS medium containing
2.2 μM BA with different combinations of NAA (2.7, 5.4 μM) and indole-3-butyric acid (IBA) (0, 2.5, 5.0 μM). Better results
were achieved when the embryonic axis was removed from the cotyledons and cultured on 1/2 MS medium supplement with 13.2 μM
BA, 2.7 μM NAA or 2.2 μM BA, 2.2 μM thidiazuron (TDZ), and 2.7 μM NAA, respectively. Regenerated shoots were successfully
rooted on 1/2 MS or Woody Plant medium (WPM) supplemented with 2.5–5.0 μM IBA. The effect of the embryonic axis, BA, and TDZ
on cotyledon regeneration was investigated in detail. Rooted plantlets were transferred to soil successfully. 相似文献
6.
Concentrations of sediment organic nitrogen, dissolved inorganic nitrogen (ammonium, nitrite and nitrate), and dissolved organic
nitrogen (DON) in sediments were measured at two sites in a eutrophic estuarine lagoon. One is a shallow aerobic site where
macrobenthos are abundant and the other is a deep anaerobic site devoid of macrobenthos. Four species of macrobenthos (Bivalvia:
Corbicula japonica, Annelida: Notomastus sp., Neanthes japonica and Oligochaeta sp.) were found in 8 sandy sediment cores
collected at a shallow site in three succcessive summers. DON (170–1500 μg atom N l-1) was the major constituent of dissolved
nitrogen with 10 times greater concentration than ammonium (55–180 μg atom N l-1) and 1000 times greater than nitrate (0.14–5.9
μg atom N l-1) and nitrite (0.21–1.4 μg atom N l-1). The ammonium content in anaerobic muddy sediments at the deep site (210–350
μg atom N l-1) was higher than in aerobic sandy sediments, whereas DON was higher in aerobic sediments than anaerobic sediments
(90–240 μg atom N l-1). In aerobic sediments, depth profiles of DIN were nearly constant whereas DON was mostly highest at
the surface. On the other hand, the increase of DON and ammonium was observed where macrobenthos was found. The occurrence
of macrobenthos and high content of DON and ammonium content in the layers of sediment may suggest the influence of macrobenthos
in the partitioning of nitrogen species through their motion and excretion.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Furmanowa Miroslawa Glowniak Kazimierz Syklowska-Baranek Katarzyna Zgórka Grazyna Józefczyk Aleksandra 《Plant Cell, Tissue and Organ Culture》1997,49(1):75-79
We have analysed the effect of some culture conditions and media components on callus growth rate and production of taxanes
in callus of Taxus × media var. Hatfieldii. For callus induction and maintenance a Gamborg B5 medium and a White - Rangaswamy
medium (WR) with different modifications were used. On an improved WR medium (containing 10 μM picloram) the callus growth
factor increased up to 5.8 fold (fresh weight). Picloram only enhanced the growth of callus, but not taxane production. On
WR medium with (100 μM) methyl jasmonate the paclitaxel content increased from 2.37 μg g-1 to 90 μg g-1 and cephalomannine
from 5.14 μg g-1 to 29.14 μg g-1 (dry weight), whereas growth of the cultures ceased. The presence of paclitaxel and cephalomannine
was established by high performance liquid chromatography.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
In the present study, a simple one medium formulation protocol for callus culture, somatic embryogenesis and in vitro production
of β-carboline alkaloids and diosgenin in Tribulus terrestris L. was developed. Extensive callus induction and proliferation was obtained in leaf explant on Murashige and Skoog (MS) medium
supplemented with 5.0 μM 6 benzyl adenine (BA) and 2.5 μM α-naphthaleneacetic acid (NAA). The embryogenic callus was maintained
on subculture to fresh parental medium at 4-week intervals over a period of 28 months. The frequency of embryo formation was
at a maximum (18.1 ± 0.9 per g of callus) on MS medium containing 5.0 μM BA and 2.5 μM NAA together with 75 mg l−1 casein hydrolysate. Globular embryo developed into torpedo stage embryo under the influence of starvation. The accumulation
of β-carboline alkaloids (harmaline and harmine) and steroidal saponin (diosgenin) in non-embryogenic and embryogenic callus
culture derived from leaf explant was compared with root, leaf, stem, and fruit of the mother plant. The embryogenic callus
accumulated equivalent amounts of harmaline (66.4 ± 0.5 μg/g dry weight), harmine (82.7 ± 0.6 μg/g dry weight), and diosgenin
(170.7 ± 1.0 μg/g dry weight) to that of the fruit of T. terrestris. The embryogenic callus culture of this species might offer a potential source for production of important pharmaceuticals. 相似文献
9.
P. I. P. Perera D. M. D. Yakandawala V. Hocher J-L. Verdeil L. K. Weerakoon 《Plant Cell, Tissue and Organ Culture》2009,96(2):171-180
The effect of growth regulators on induction of androgenesis in coconut was investigated using seven different growth regulators
at various concentrations and combinations. Three auxins (1-naphthalene acetic acid—NAA, indoleacetic acid—IAA, picloram)
and three cytokinins (2-isopentyl adenine-2-iP, kinetin, zeatin) were tested either alone or in combination with 2,4-dichlorophenoxyacetic
acid (2,4-D), using modified Eeuwens Y3 liquid medium as the basal medium. Among the tested auxins, 100 μM NAA in combination
with 100 μM 2,4-D enhanced the production of calli/embryos (123) whereas IAA and picloram showed negative and detrimental
effects, respectively, for androgenesis induction over 100 μM 2,4-D alone. Kinetin and 2-iP enhanced the production of calli/embryos
when 100 μM 2,4-D was present in the culture medium. Both cytokinins at 10 μM yielded the highest frequencies of embryos (113
and 93, respectively) whereas zeatin (1 or 2.5 μM) had no impact on microspore embryogenesis. When calli/embryos (produced
from different treatments in different experiments) were sub-cultured in somatic embryo induction medium (Y3 medium containing 66 μM 2,4-D), followed by maturation medium (Y3 medium without growth regulators) and germination medium (Y3 medium containing 5 μM-6-benzyladenine—BA and 0.35 μM gibberellic acid—GA3), plantlets were regenerated at low frequencies (in most treatments ranging from 0% to 7%). 相似文献
10.
A. L. Kulikova N. A. Kuznetsova V. P. Kholodova 《Russian Journal of Plant Physiology》2011,58(5):836-843
The effects of increase copper concentrations in medium (10–150 μM CuSO4) on growth and viability of the roots of two-week-old soybean seedlings (Glycine max L., cv. Dorintsa) were studied. Copper excess suppressed biomass accumulation and linear plant growth; copper affected root
growth much stronger than shoot growth. The presence of 10 μM CuSO4 in medium suppressed accumulation of plant biomass by 40% and the root length by 70%; in the presence of 25 μM CuSO4, these indices were equal to 80 and 90%, respectively. In the presence of 50 μM CuSO4, roots ceased to grow but biomass and shoot length still increased slightly. 150 μM CuSO4 was lethal for plants. The earliest sign of excessive copper toxicity was the accumulation of MDA, indicating activation
of membrane lipid peroxidation. A significant increase in MDA content was observed at plant incubation in medium with 10 μM
CuSO4 for 1 h; in this case, the content of copper in the roots increased from 36 ±1.8 (in control) to 48 ± 2.4 μg/g dry wt. The
number of dead cells (permeable for the dye Evans Blue) was doubled in the presence of 200 μg/g dry wt within the root; this
occurred in 72 h of growth in medium with 10 μM CuSO4, in 6 h at 25 μM CuSO4, in 3 h at 50 μM CuSO4, and 1 h at 150 μM CuSO4. Toxicity of copper excess was manifested stronger in dividing and elongation cells of the root apex (root meristem and the
zone of elongation) than in more basal root regions. Copper excess resulted in the formation of breaks in the surface cell
layers of the root tips and affect root morphology. When plant grew in medium with 10 μM CuSO4, a distance of lateral root formation zone from the root tip decreased markedly, and spherical swellings were formed on the
tips of lateral roots. The higher copper concentrations (50 and 150 μM) suppressed completely the development of lateral roots. 相似文献
11.
Małgorzata Malik 《Plant Cell, Tissue and Organ Culture》2008,94(3):337-345
Alternative procedures for the production of Narcissus L. somatic embryos were investigated. Somatic embryogenesis was initiated on ovary explants isolated from cv. Carlton bulbs,
chilled for 12 weeks at 5°C. The explants were cultured on MS media with 3% sucrose and growth regulators: Picloram or 2,4-D
(10 or 25 μM) and BA (1 or 5 μM) for 12 weeks in the culture systems: continuous cultivation on solid media, continuous cultivation
in liquid media and sequential cultivation using cycles in liquid and solid media. Two types of somatic embryogenesis, indirect
and direct, were observed. The developmental pathway depended on the period of exposure to liquid media. Somatic embryos were
formed via embryogenic nodular callus on solid media. 2,4-D and BA stimulated the process. The 4-week and 8-week liquid medium
treatments resulted in the development of somatic embryos directly from the ovary explant tissue. The highest number of somatic
embryos was noted under the influence of 25 μM 2,4-D and 5 μM BA in explants cultivated for 8 weeks in liquid medium and then,
for 4 weeks, on solid medium. The effects of inoculum density on biomass increase and the formation of somatic embryos in
cultures obtained on a medium with 25 μM 2,4-D and 5 μM BA were also checked. The highest biomass increase was observed after
subculturing in liquid medium containing 0.5 μM NAA and 5 μM BA when the density of inoculum was 0.5 g/25 ml of the medium.
The highest number of somatic embryos was noted when the density of inoculum was 1.5 g/25 ml. 相似文献
12.
Embryogenic cultures were induced from leaflets from new vegetative flushes of mature ‘Brewster’ litchi trees on B5 medium
containing 400 mg l−1 glutamine, 200 mg l−1 casein hydrolysate, 30 g l−1 sucrose, 4.52 μM 2,4-D, 9.30 μM kinetin and 3 g l−1 gellan gum in darkness. Embryogenic cultures consisting of proembryonic cells and masses were maintained either on semi-solid
MS medium supplemented with 4.52 μM 2,4-D and 0.91 μM zeatin or as embryogenic suspension cultures in liquid medium of the
same composition. Maturation of somatic embryos occurred on semi-solid MS medium with 5–20% (v/v) filter-sterilized coconut
water in darkness. Recovery of plants from somatic embryos was improved with 14.4 μM GA3 on half-strength MS medium with 0.2 g l−1 activated charcoal under a 16 h photoperiod provided by cool white fluorescent lights (60–80 μmol s−1 m−2). Plants have been successfully acclimatized in the greenhouse. 相似文献
13.
Raya Liberman Liat Shahar Ada Nissim-Levi Dalia Evenor Moshe Reuveni Michal Oren-Shamir 《Plant Cell, Tissue and Organ Culture》2010,100(3):345-348
A protocol for plantlet regeneration through shoot formation was developed for the neotropical shrub Brunfelsia calycina. This shrub is unique in its change in flower color from dark purple to white. Explants from young and mature leaves were
incubated on MS medium (pH 5.7, 30 g/l sucrose, 7.5 g/l agar) with various combinations of Indole-3-acetic acid (IAA) and
6-Benzyladenine (BA) under a 16 h photoperiod at a constant temperature of 25°C. Shoot emergence was best at 4.44 μM BA and
2.85 μM IAA for young leaf explants, and at 8.88 μM BA, 2.85 μM IAA for mature leaf explants. When shoots were transferred
to MS medium supplemented with 1.23–2.46 μM indole butrytic acid (IBA), they developed roots. 相似文献
14.
The effects of growth regulators, cold-pretreatment of flower buds, ovule (embryo sac) developmental stage and genotype on
induction of gynogenesis in unpollinated ovule cultures were assessed in niger (Guizotia abyssinica (L. f.) Cass.). Indirect callus-mediated gynogenesis occurred in cvs JNC-6 and Ootacamund when the ovules were cultured on
MS medium supplemented with 30 g l−1 sucrose and 2,4-D either alone (0.5–2.0 μM) or in combination (2.0 μM) with different cytokinins, such as adenine, BA, 2iP
and kinetin (0.5–2.0 μM). An optimum induction of gynogenesis was fostered on medium supplemented with 2.0 μM 2,4-D and 1.0 μM
kinetin. Cold-pretreatment of flower buds had no stimulatory effect, but ovules collected one day before anthesis were most
responsive to gynogenesis. The results showed significant variations in genotypic competence for gynogenesis with cv. Ootacamund
being the most responsive (12.5%) and cv. IGP-76 the least (2.5%). Gynogenic embryos differentiated and matured on media (30 g l−1 sucrose) supplemented with 0.5 μM NAA plus 1.0 μM kinetin, and 0.5 μM ABA, respectively. The haploidy (2n = 1x = 15) of gynogenic plants was confirmed by cytological analysis. 相似文献
15.
A protocol for plant regeneration from mesophyll and callus protoplasts of Robinia pseudoacacia L. was developed. For leaves from in vitro raised shoots, an enzyme combination of 2.0% cellulose and 0.3% macerozyme for
a digestion period of 20 h resulted in the best yield of protoplasts (9.45 × 105 protoplast/g fresh weight). Mesophyll-derived protoplasts started cell wall regeneration within 24 h of being embedded in
Nagata and Takebe (NT) medium supplemented with 5 μM NAA and 1 μM BAP followed by the first cell division on day three of
culture and micro-colony (32 cells) formation within day 7–10 in the same medium. However, using callus as the starting material,
a combination of 2.0% cellulose and 1.0% macerozyme for a digestion period of 24 h gave the highest protoplast yield (3.2 × 105 protoplast/g fresh weight). Cell wall regeneration in callus-derived protoplasts started within 24 h followed by the first
cell division on the day three (96 h) and the appearance of microcolonies of more than 32 cells by the end of first week (144 h)
of culture on solid WPM medium supplemented with 5 μM NAA and 1 μM BAP. Microcalli were visible to the naked eye after 45 days
on solid WPM medium. Proliferation of macro-calli was successfully accomplished on solid Murashige and Skoog (MS) medium with
5 μM NAA and 5 μM BAP. Both mesophyll and callus protoplast-derived calli produced shoots on MS medium with 0.5 μM NAA and
1 μM BAP within 25–30 days and multiplied on MS medium with 1.25 μM BAP. Excised microshoots were dipped in 1–2 ml of 2.0 μM
IBA for 24 h under dark aseptic conditions and transferred to double sterilized sand for rooting. The flasks containing sand
were inoculated with Rhizobium for in vitro nodulation. Forty-five plants transferred to pots in the glasshouse established well. 相似文献
16.
Priyanka Srivastava Naresh Kasoju Utpal Bora Rakhi Chaturvedi 《Plant Cell, Tissue and Organ Culture》2009,99(1):1-7
Several secondary metabolites are present in Lantana camara L. as its leaves serve as reservoirs for various bioactive compounds. Callus cultures of L. camara were induced from leaf discs incubated on Murashige and Skoog medium supplemented with 5 μM 6-benzyladenine, 1 μM 2,4-dichlorophenoxyacetic
acid, and 1 μM α-naphthalene acetic acid (NAA). An aqueous extract (0.23%), obtained from these calli (50 g dry mass), had
an apparent cytotoxic effect on HeLa cells with an IC50 value of 1,500 μg/ml in 36 h. A dose-time dependent activity of the extract was established wherein higher dosage exhibited
increased activity; however, over time cell necrosis was observed. 相似文献
17.
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
18.
L. A. Stetsenko N. I. Shevyakova V. Yu. Rakitin Vl. V. Kuznetsov 《Russian Journal of Plant Physiology》2011,58(2):337-343
Atropa belladonna L. plants were grown in water culture for 8 weeks before the nutrient medium was supplemented with NiCl2 to final concentrations of 0 (control treatment), 50, 100, 150, 200, 250, and 300 μM. After 4 days of plant growing in the
presence of nickel chloride, the content of water, proline, Ni, Fe, free polyamines, as well as lipid peroxidation rates were
measured. The addition of 100–150 μM Ni to the medium significantly reduced the fresh weight increments and water content
in comparison with these parameters for untreated plants; 200 μM Ni caused serious, although nonlethal damage to the plants,
whereas 250 and 300 μM Ni proved to be lethal. In the aboveground organs, the major part of Ni was accumulated in the apical
leaves. When the plants were treated with 200 μM Ni, the Ni content in apical leaves was 220 μg/g dry wt, while Ni content
in roots reached 1500 μg/g dry wt. The treatment of plants with proline in the presence of 200 μM Ni inhibited Ni accumulation
in tissues. The proline-treated plants exhibited elevated iron content in leaves and especially in roots and were characterized
by comparatively low rates of lipid peroxidation and by sustained leaf water status. When 200 μM Ni was applied, the content
of free putrescine decreased, while the contents of spermine and spermidine in leaves increased appreciably with respect to
the control values. The toxic effect of nickel was accompanied not only by an enhanced accumulation of high- molecular-weight
polyamines but also by their oxidative degradation, which was evident from the 14-fold increase in the content of 1,3-diaminopropane.
The protective effect of exogenous proline in the presence of high nickel concentrations was manifested in lowered lipid peroxidation
rates, alleviation of iron deficiency, and in retarded oxidative degradation of polyamines. 相似文献
19.
Somatic embryogenesis was induced in embryogenic calli of Spinacia oleracea L., on a Murashige and Skoog (1962) medium, containing
4.6 μM kinetin as the sole growth regulator. Abscisic acid, gibberellic acid, and indole-3-acetic acid were supplemented to
kinetin-containing medium and their effects on the initiation of somatic embryos was studied. Abscisic acid at a particular
concentration (4 μM) dramatically increased the number of embryos per g fresh weight of callus, while both gibberellic acid
and indole-3-acetic acid suppressed the embryo initiation. It is suggested that the promoting effect of abscisic acid on the
embryo initiation may be explained as a stress response of the tissue. The relative number of globular embryos vs. the embryos
in heart/torpedo and cotyledonary stages was increased at 4 μM abscisic acid and at all gibberellic acid concentrations (0.3–10
μM). In contrast, the ratio of globular to polar embryos was lower than in controls at 1 μM abscisic acid and indole-3-acetic
acid (1 and 10 μM). The effects of growth regulators on the ratio of globular to polar embryos indicate that they interfere
with the normal distribution of cell division and cell expansion during early embryogenesis.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
20.
Mustapha Benmoussa Sandip Mukhopadhyay Yves Desjardins 《Plant Cell, Tissue and Organ Culture》1997,47(1):91-94
The effects of different growth regulators on induction and growth of callus ofAsparagus densiflorus cv. Sprengeri were studied. Calluses grew more rapidly on Murashige and Skoog basal medium supplemented with 5.4 μM p-chlorophenoxyacetic
acid (pCPA) and 4.4 μM 6-benzylaminopurine (BA) (medium 1) as compared to the same medium with 11.3 μM 2,4-dichlorophenoxyacetic
acid (2,4-d) and 4.6 μM kinetin (medium 2). Calluses on medium 1 were soft and friable, whereas, compact, hard calluses originated on
medium 2. Different concentrations and combinations of BA and/or kinetin were also used to study their effects on shoot regeneration.
Kinetin was found to be less effective than BA in the initiation of shoots (1.8 shoots/callus). High numbers of shoots were
produced in the presence of 0.4 μM BA alone (3.3 shoots/callus). The addition of ancymidol (5 μM) in MS with 0.4 μM BA enhanced
multiplication of shoots (9.8 shoots/explant) and also produced well-developed crowns. 相似文献