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71.
Aribaud Marcel Kevers Claire Martin-Tanguy Josette Gaspar Thomas 《Plant Cell, Tissue and Organ Culture》1998,55(2):85-94
Foliar discs (8 mm diameter) from expanding leaves of the middle part of vegetative shoots of Chrysanthemum morifolium Ramat
raised in vitro were induced to form directly on specific media in vitro either roots or vegetative buds, or callus. The budding
programme, on its specific medium, was deviated to callus formation by the addition of 2 mM β-OH-E (β-OH-ethyldrazine, an
inhibitor of diamine oxidase). Conversely vegetative buds instead of callus were formed on the callus medium in the presence
of 2 mM DFMO (difluoromethylornithine, an inhibitor of ornithine decarboxylase). Callus formation was characterized by high
accumulation of free and particularly conjugated polyamines (PA), very low or undetectable activities of diamine- and polyamine
oxidases, and transglutaminase. DFMO-deviation of callus initiation in favour of bud formation lowered the accumulation of
PA and increased the activity of amine-oxidases. The high catabolism of PA in the organogenic (rooting, budding) programs
was questioned as to its role in developmental processes.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
72.
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
73.
The effects of various growth regulators on morphogenesis from cocoyam tissues (Xanthosoma sagittifolium) were investigated.
Calluses were initiated from shoot tip and petiole explants and proliferated on medium containing 1.36 μM dicamba. Callus
production was significantly greater from petioles than from shoot tips. Thidiazuron (0.045 μM) enhanced callus production
when dicamba (13.5 μM) was used, and was more favorable to petioles than shoot tips. Friable shoot tip callus was subcultured
into liquid media containing either 1.36 μM dicamba alone, 1.35 μM 2,4-D + 0.46 μM kinetin or 1.36 μM dicamba + 0.46 μM kinetin
to induce adventive regeneration. Tissues producing single or aggregated shoot buds were subcultured into media containing
0, 0.049 and 0.49 μM 2-isopentenyladenine where bud multiplication and shoot regeneration were observed. Bud aggregates were
formed from callus in liquid cultures containing 1.36 μM dicamba, 1.36 μM dicamba + 0.46 μM kinetin or 1.35 μM 2,4-D + 0.46
μM kinetin. Shoot bud clumps which remained green produced shoots, daughter buds, and plantlets in stationary and agitated
liquid media containing 0, 0.049 and 0.49 μM 2iP.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
74.
Frequency of somatic embryogenesis from callus cultures derived from immature cotyledon explants of Simarouba glauca Linn. was highest on solid MS medium supplemented with 11.1 M benzyladenine and 13.42 M -naphthaleneacetic acid. On transfer of the somatic embryos into maturation medium containing half-strength MS medium supplemented with 1.89 M abscisic acid (ABA) and 2% (w/v)sucrose, 20–25 % of embryos germinated within 20 days of culture with distinct cotyledon, hypocotyl and radicle. 相似文献
75.
Phenylalanine ammonia-lyase (PAL) activity increased 8- to 12-fold in pine (Pinus elliotii Engelm.) callus tissue within 2 days after subculturing on fresh medium. Factors such as increasing the sucrose content of the media, imposing additional tissue in jury or subculturing more frequently did not cause additional stimulation of PAL activity. The rapid increase in PAL activity appeared to be due to enzyme activation, since cycloheximide did not appreciably reduce the stimulation of PAL activity. The subsequent loss of increased PAL activity with age was reduced by cycloheximide and a cool growth environment. 相似文献
76.
6-(2,3,4-trihydroxy-3-methylbutylamino) purine (trihydroxyzeatin) applied to soybean callus is metabolised slowly. After 48 h only one peak of biological activity which co-eluted with the applied cytokinin was detected. When the callus was incubated on a medium which contained 10–5 M trihydroxyzeatin, spiked with 8 {14C} trihydroxyzeatin, for 28 days, three peaks of biological activity and three peaks of radioactivity were detected. One of the biologically active and radioactive peaks co-eluted with zeatin. Another of the radioactive peaks co-eluted with N-(purin-6-yl) glycine. From the data obtained it apears that trihydroxyzeatin can be both oxidized and reduced by soybean callus. The potential to be converted to zeatin may explain why trihydroxyzeatin and its parent compound, which is usually rapidly metabolised by living material, are equally active in the soybean callus bioassay. From the radioactive data obtained it appears that trihydroxyzeatin is susceptible to oxidation to form N-(purin-6-yl) glycine. 相似文献
77.
P. K. Asha M. S. Shaila C. S. Vaidyanathan T. Ramakrishnan 《Journal of biosciences》1979,1(3):327-334
Treatment ofTrigonella foenumgraeceum (fenugreek) seedlings with naphthalene acetic acid plus gibberellic acid enhanced the RNA synthesising capacity of nuclei
isolated from the hypocotyl and cotyledonary regions. This increase was more pronounced in the nuclei from the hypocotyl region
than from the cotyledonary region.In vitro addition of these phytohormones did not stimulate RNA synthesis by nuclei. The RNA synthesis by mitochondria was not affected
by preincubating the seedlings with the hormones. The nuclei isolated from callus cultures of fenugreek hypocotyl treated
with the hormone also showed increased RNA synthesis. 相似文献
78.
Induction of callus and plant regeneration in Vicoa indica 总被引:1,自引:0,他引:1
Callus cultures were initiated from the stem and leaf explants of aseptically grown Vicoa indica. A simple method is described for plant regeneration from callus and the rapid multiplication of the plants thus obtained. Callus initiation was optimum in Gamborg B5 (B5) basal medium containing either 2.0 mg l-1 naphthaleneacetic acid (NAA) with 0.2 mg l-1 kinetin (Kn) or 2.0 mg l-1 6-benzylaminopurine (BAP) with 0.2 mg l-1 NAA. The calli initiated on B5 medium were able to proliferate on both Murashige and Skoog (MS) and B5 basal medium. Shoot primordia were obtained from greenish callus on passage to B5 basal medium containing 3.0 mg l-1 BAP and 1.0 mg l-1 Kn. On further subculture onto B5 medium containing 0.2 mg l-1 Kn the shoot primordia developed into plantlets. 相似文献
79.
Leaf segments of a monohaploid, dihaploid and tetraploid genotype of the potato (Solanum tuberosum; x = 12) were cultured on callus-inducing medium with 10, 20, 30 or 40 gl–1 sucrose. After 5 and 7 days of culture, metaphases contained the somatic or polyploidized number of mono- or diplochromosomes. The percentages of polyploidized metaphases were inversely correlated with the number of chromosome sets of the genotypes. In monohaploid leaf segments the percentages of polyploidized metaphases and of metaphases with diplochromosomes increased when the sucrose concentration was raised from 10 or 20 to 30 gl–1 and remained constant or decreased from 30 to 40 gl–1. Higher concentrations of sucrose but not higher osmolalities of the medium due to mannitol induced endoreduplication in more cells. The frequency of polyploidized metaphases and metaphases with diplochromosomes in dihaploid and tetraploid leaf segments remained constant through increases in sucrose concentrations. 相似文献
80.
Steven R. Hagen Duane LeTourneau Paul Muneta Janice Brown 《Plant Growth Regulation》1990,9(4):341-345
Callus cultures of 7 potato cultivars were initiated from tuber tissue and maintained on Gelrite-solidified media with 1–20 M picloram as the only PGR. Ten M picloram was the optimal concentration for callus induction. By 4–6 weeks after explanting, there was sufficient callus produced for subculture to maintenance media which contained 1–20 M picloram as the only PGR. When grown in the dark at 25°C, subcultured callus typically increased 10-fold in wet weight in 4–5 weeks. The callus produced was friable and a light grey to cream color. Callus cultures were used to establish cell suspension cultures. Callus and cell suspension cultures have been maintained for over 2 years on the picloram containing media.Abbreviations BA
benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- MS
Murashige-Skoog
- NAA
naphthaleneacetic acid
- PGR
plant growth regulator
Research paper #9053 of the Idaho Agricultural Experiment Station. 相似文献