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1.
An effective protocol was developed for in vitro regeneration of the Melothria maderaspatana via indirect organogenesis in liquid and solid culture systems. Organogenesis was achieved from liquid culture calluses derived from leaf and petiole explants of mature plants. Organogenic calluses (98.2?±?0.36 and 94.8?±?0.71%) were induced from both leaf and petiole explants on Murashige and Skoog (MS) liquid medium containing 6.0 µM 2,4-dichlorophenoxyacetic acid (2,4-D) and 0.5 µM thidiazuron (TDZ); and 6.0 µM 2,4-D and 1.0 µM benzyladenine (BA) combinations, respectively. Adventitious shoot regeneration (68.2?±?0.06 shoots per explant) was achieved on MS medium supplemented with 2.0 µM BA, 4.0 µM TDZ, 10% v/v coconut water and 0.06 mM glutamine from leaf-derived calluses. Petiole-derived calluses produced adventitious shoots (45.4?±?0.09 shoots per explant) on MS medium fortified with 2.0 µM BA, 4.0 µM TDZ, 10% v/v coconut water, and 0.08 mM glutamine. Elongation of shoots occurred in MS medium with 2.0 µM gibberellic acid (GA3). Regenerated shoots (2–3 cm in length) rooted (74.2?±?0.38%) and hardened (85?±?1.24%) when they were transferred to 1/2-MS medium supplemented with 3.0 µM indole-3-butyric acid (IBA) followed by garden soil, vermiculate, and sand (2:1:1 ratio) mixture. The elongated shoots (4–5 cm in length) were exposed simultaneously for rooting as well as hardening (100%) in moistened [(1/8-MS basal salt solution with 5 µM IBA and 100 mg l?1 Bavistin® (BVN)] garden soil, vermiculate, and sand (2:1:1 ratio) mixture. Subsequently, the plants were successfully established in the field. The survival percentage differed with seasonal variations.  相似文献   

2.
The effect of various hormonal combinations on callus formation and regeneration of shoot and root from leaf derived callus of Acanthophyllum sordidum Bunge ex Boiss. has been studied. Proteins and activity of antioxidant enzymes were also evaluated during shoot and root organogenesis from callus. Calli were induced from leaf explants excised from 30-d-old seedlings grown on Murashige and Skoog medium containing 4.52 μM 2,4-dichlorophenoxyacetic acid + 4.65 μM kinetin. Maximum growth of calli and the most efficient regeneration of shoots and roots occurred with 2.69 μM 1-naphthalene acetic acid (NAA), 2.69 μM NAA + 4.54 μM thidiazuron and 2.46 μM indole-3-butyric acid. Protein content decreased in calli and increased significantly during regeneration of shoots from callus. Superoxide dismutase activity decreased in calli comparing to that of seedlings, then increased in regenerated shoots and roots. High catalase activity was detected in seedlings and regenerated shoots, whereas high peroxidase activity was observed in calli and regenerated roots.  相似文献   

3.
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   

4.
The effect of various hormonal combinations on regeneration of shoots and roots from meristem-derived callus of Crocus sativus L. and activities of antioxidant enzymes have been studied. The most efficient regeneration occurred with 1.0 mg dm−3 1-naphthaleneacetic acid (NAA) + 1.0 mg dm−3 thidiazuron and 1.0 mg dm−3 NAA + 2.0 mg dm−3 kinetin. For sprouting, regenerated shoot were subcultured on Murashige and Skoog medium containing 1.0 mg dm−3 NAA + 1.0 mg dm−3 benzylaminopurine (BAP). Protein content and superoxide dismutase activity decreased in regenerated shoots and roots and increased in sprouting shoots, while catalase (CAT), peroxidase (POX) and polyphenol oxidase (PPO) activities increased during organogenesis and decreased in sprouting shoots. High CAT and PPO activities were detected in regenerated roots, whereas high POX activity was observed in regenerated shoot.  相似文献   

5.
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   

6.
The aim of the present study was to examine the antioxidant activity of three Veronica species (Plantaginaceae). The antioxidant potential of various extracts obtained from aerial flowering parts was evaluated by DPPH-free (1,1-diphenyl-2-picrylhydrazyl-free) radical scavenging activity and ferric-reducing antioxidant power assays. Considerable antioxidant activity was observed in the plant samples (FRAP values ranged from 0.97 to 4.85 mmol Fe2+/g, and DPPH IC50 values from 12.58 to 66.34 μg/ml); however, these levels were lower than the activity of the control compound butylated hydroxytoluene (BHT) (FRAP: 10.58 mmol Fe2+/g; DPPH IC50: 9.57 μg/ml). Also, the in vivo antioxidant effects were evaluated in several hepatic antioxidant systems in rats (activities of glutathione peroxidase, glutathione reductase, peroxidase, catalase, xanthine oxidase, glutathione content and level of thiobarbituric acid reactive substances) after treatment with different Veronica extracts, or in combination with carbon tetrachloride (CCl4). Pretreatment with 100 mg/kg b.w. of Veronica extracts inhibited CCl4-induced liver injury by decreasing TBA-RS level, increasing GSH content, and bringing the activities of CAT and Px to control levels. The present study suggests that the extracts analyzed could protect the liver cells from CCl4-induced liver damage by their antioxidative effect on hepatocytes.  相似文献   

7.
Many of the effects of carnitine are ascribed to its antioxidant properties. The aim of this study was to evaluate the antioxidant properties of carnitine in vitro. Carnitine was found to decolorize ABTS•+, and to protect fluorescein against bleaching induced by AAPH-derived peroxyl radicals and peroxynitrite, thiol groups against oxidation induced by hydrogen peroxide, peroxyl radicals, hypochlorite and peroxynitrite, and erythrocytes against hemolysis induced by peroxyl radicals and hypochlorite. These results show that carnitine has a direct antioxidant action against physiologically relevant oxidants.  相似文献   

8.
Six pea (Pisum sativum L.) cultivars (Adept, Komet, Lantra, Olivin, Oskar, Tyrkys) were transformed via Agrobacterium tumefaciens strain EHA105 with pBIN19 plasmid carrying reporter uidA (β-glucuronidase, GUS, containing potato ST-LS1 intron) gene under the CaMV 35S promoter, and selectable marker gene nptII (neomycin phosphotransferase II) under the nos promoter. Two regeneration systems were used: continual shoot proliferation from axillary buds of cotyledonary node in vitro, and in vivo plant regeneration from imbibed germinating seed with removed testa and one cotyledon. The penetration of Agrobacterium into explants during co-cultivation was supported by sonication or vacuum infiltration treatment. The selection of putative transformants in both regeneration systems carried out on media with 100 mg dm−3 kanamycin. The presence of introduced genes was verified histochemically (GUS assay) and by means of PCR and Southern blot analysis in T0 putative transformants and their seed progenies (T1 to T3 generations). Both methods, but largely in vivo approach showed to be genotype independent, resulting in efficient and reliable transformation system for pea. The in vivo approach has in addition also benefit of time and money saving, since transgenic plants are obtained in much shorter time. All tested T0 – T3 plants were morphologically normal and fertile.This research was supported by the National Agency for Agricultural Research (grants No. QE 0046 and QF 3072) and Ministry of Education of the Czech Republic (grant No. ME 433).  相似文献   

9.
Three Lactobacillus strains (LOCK 0900, LOCK 0908, LOCK 0919) out of twenty-four isolates were selected according to their antagonistic activity against pathogenic bacteria, resistance to low pH and milieu of bile salts. Intragastric administration of a mixture of these strains to Balb/c mice affected cytokine TH1-TH2 balance toward nonallergic TH1 response. Spleen cells, isolated from lactobacilli-treated mice and re-stimulated in vitro with the mixture of heat-inactivated tested strains, produced significantly higher amounts of anti-allergic tumor necrosis factor- and interferon-γ than control animals whereas the level of pro-allergic interleukin-5 was significantly lower. Lactobacillus cells did not translocate through the intestinal barrier into blood, liver and spleen; a few Lactobacillus cells found in mesenteric lymph nodes could create antigenic reservoir activating the immune system. The mixture of Lactobacillus LOCK 0900, LOCK 0908 and LOCK 0919 strains represents a probiotic bacterial preparation with possible use in prophylaxis and/or therapy of allergic diseases.  相似文献   

10.
Cre/LoxP mediated chromosomal engineering in embryonic stem (ES) cells has a variety of applications, including the creation of model systems for studying aneuploidy. Targeted meiotic recombination (TAMERE) was proposed as a high efficiency in vivo alternative to effect Cre-mediated recombination, in which Cre recombinase under control of the Synaptonemal Complex 1 promoter is expressed during male meiosis in transgenic mice. TAMERE has been successfully used with LoxP sites up to 100 kb apart. We tested TAMERE for a chromosome engineering application in which LoxP sequences were integrated into sites 3.9 Mb apart on the same (cis) or opposite (trans) copies of mouse Chromosome 16 (MMU16). TAMERE was ineffective in generating either a deletion or a translocation in vivo. The TAMERE method may be of limited use for large genomic rearrangements. The desired translocation was achieved with an in vitro method that can be used in any ES cell line. Mice produced from the reciprocal duplication/deletion of MMU16 in a region homologous to human chromosome 21 provide models that are useful in studies of Down syndrome.  相似文献   

11.
We have developed a protocol for the in vitro propagation of the genus Clivia. Shoots were regenerated when fragments of the peduncle-pedicel junction (PP junction) from young inflorescences were used as explants. The optimal media for PP junction were Murashige and Skoog (MS)-based medium containing 10 M of 6-benzyladenine (BA) and 10 M of 2,4-dichlorophenoxyacetic acid (2,4-D) or MS supplemented with 5 M BA, 10 M -naphthaleneacetic acid (NAA), 250 mg l-1 glutamine and 500 mg l–1 casein hydrolysate and their usage depended on the breeding lines. Multiplication from initiations and in vitro seedlings was the best when the explants were cut longitudinally through the meristem and placed on MS plus 44 M BA. Plantlets were transferred on to hormone -free MS medium with charcoal for rooting.  相似文献   

12.
Summary Shoot apex, nodal, and leaf explants of Stevia rebaudiana Bertoni can regenerate shoots when cultured on Murashige and Skoog (MS) medium supplemented with 6-benzyladenine (BA; 8.87 μM) and indole-3-acetic acid (5.71 μM). Rooting of the in vitro-derived shoots could be achieved following subculture onto auxin-containing medium. A survival rate of 70% was recorded at the hardening phase on the substrate cocopeat. The presence of the sweet diterpene glycosides, viz. stevioside and rebaudioside, was confirmed in the in vitro-derived tissues of Stevia using HPTLC techniques. Callus cultured on agar-solidified MS medium supplemented with BA (8.87 μM) and indole-3-butyric acid (9.80 μM) showed the highest sweetener content.  相似文献   

13.
Escherichia coliL-asparaginase, an antileukaemic agent in man1, inhibits in vitro mitogen or antigen-induced blastogenesis in man2,3 and in animals (M. Bennett, E. G. Mayhew and T. Han, unpublished data) and suppresses bone-marrow derived antibody precursor cells in the mouse4. We now report that another L-asparaginase preparation—from Erwinia carotovora—also possesses antileukaemic activity5,6 and has a more pronounced immunosuppressive effect on in vitro blastogenesis than the E. coli enzyme.  相似文献   

14.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

15.
Berberis buxifolia Lam., known as “Calafate”, is a plant native to Argentina that exhibits antimicrobial activity. This biological activity is attributed to the isoquinoline alkaloid berberine. The aim of this research was to test the antimicrobial properties of different extracts of this species, taking berberine as the reference molecule, and to examine if the expression of bacterial multidrug resistance (MDR) efflux pumps could be responsible for possible resistance mechanisms. To this end, a wild-type and a mutant strain of Staphylococcus aureus with a defective MDR efflux pump were used and the minimum inhibitory concentrations of the extracts were determined. The studies were carried out with infusions of in vivo shoots and “Calafate” commercial tea, as well as with the media derived from shoot cultures incubated with different plant growth regulators (thidiazuron, picloram, and jasmonic acid). As far as antimicrobial activity is concerned, all the extracts tested were significantly more effective than berberine standard. “Calafate” commercial tea and shoot tea had inhibitory concentrations similar to the one observed for ampicillin standard. The media from the shoot cultures, however, were significantly more effective than all the others, particularly the one derived from jasmonic acid, suggesting the presence of compounds that could be acting synergistically with berberine. There were no differences in antimicrobial activity against the wild-type and the mutant S. aureus; no definite conclusions could be drawn concerning the relationship between MDR pumps and possible pathogen resistance to extracts of B. buxifolia.  相似文献   

16.
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   

17.
Among 31 3,4-dihydro-s-triazinobenzimidazole derivatives tested 12 compounds showedin vitro antimicrobial activity against G+ bacteria. Best results were obtained with substances containing naphthyl or halogenated phenyl group on the triazine ring. The tested derivatives had no significantin vitro antimicrobial activity against either the used G species or fungi.  相似文献   

18.
Bigtooth maple (Acer grandidentatum) is a promising ornamental tree that is not widely used in managed landscapes. Tissue culture has not been used successfully to propagate this taxon. We cultured single- and double-node explants from greenhouse-grown, 2-y old seedlings of bigtooth maples, which are indigenous to New Mexico, Texas, and Utah, on Murashige–Skoog (MS), Linsmaier–Skoog (LS), Driver–Kuniyuki Walnut (DKW), and Woody Plant (WPM) tissue culture media. Media affected shoot proliferation (P = 0.0242) but the zone of explant origin (P = 0.7594) did not. After four 30-d subcultures, explants on DKW media and WPM media produced 3.6 and 3.5 shoots per explant, respectively. Sprouting rates were highest on DKW, making DKW the best overall media for shoot proliferation. Double-node microshoots were rooted in vitro on DKW containing indole acetic acid (IAA). Microshoots represented six genotypes from three locations within Texas and New Mexico. Rooting percentage increased up to 15% as IAA concentration increased (P = 0.0040). There was 100% survival of rooted microshoots in vented Phytatrays containing one perlite: one peat moss (v/v). We conclude that DKW can be used to proliferate microshoots, and IAA induces rooting in microshoots of bigtooth maple.  相似文献   

19.
Different concentrations of methyl jasmonate, spermine, casein hydrolysate, or progesterone combined with 16 mg/l 2 iP + 4 mg/l naphthalene acetic acid (NAA) were investigated in order to obtain higher multiplication rate and growth of Hippeastrum vittatum bulbs in vitro on MS basal medium. The highest multiplication rate (8.2 bulbs/explant) was attained with 80 mg/l spermine, while the highest bulb fresh weight (1.23 g/bulblet) was obtained with 4 mg/l methyl jasmonate. Progesterone at 20 mg/l or casein hydrolysate at 2.0 g/l gave the highest leaf length (14.1 and 13.2 cm, respectively). So, it can be advised to use 80 mg/l spermine combined with 16 mg/l 2 iP + 4 mg/l NAA to obtain the highest number of bulbs per explant with moderate leaf length and bulb fresh weight. Chemical analysis showed alternations in the alkaloid type ratio and number of compounds in the bulbs treated with methyl jasmonate (4 mg/l).  相似文献   

20.
An efficient micropropagation protocol was established for Capsicum chinense Jacq. cv. Umorok, a pungent chilli cultivar. Shoot-tip explants were cultured on Murashige and Skoog (MS) medium containing cytokinins (22.2–88.8 μM 6-benzylaminopurine, BAP, 23.2–93.0 μM kinetin, Kin, or 22.8–91.2 μM zeatin, Z) alone or in combination with 5.7 μM indole-3-acetic acid (IAA). Maximum number of shoots were induced on medium containing 91.2 μM Z or 31.1 μM BAP with 4.7 μM Kin. The separated shoots rooted and elongated on medium containing 2.5 or 4.9 μM indole-3-butyric acid (IBA). Axillary shoots were induced from in vitro raised plantlets by decapitating them. The axillary shoot-tip explants were used for further multiple shoot buds induction. A maximum of about 150 plantlets were obtained from a single seedling. Hardened and acclimatized plantlets were successfully established in the soil.  相似文献   

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