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Teodora Janković Branka Vinterhalter Dijana Krstić-Milošević Radomirka Nikolić Dragan Vinterhalter Slobodan Milosavljević 《Acta Physiologiae Plantarum》2011,33(4):1515-1520
Shoot cultures of Gentianella bulgarica established from seedling epicotyls were maintained on MS medium supplemented with BA 0.2 mg l−1 + NAA 0.1 mg l−1. Cultures were prone to precocious flowering requiring the use of small shoot buds for multiplication purposes. The contents
of three xanthone compounds identified as DGL, BGL, and DMB, in different plant material were determined by HPLC. The analysis
revealed that the production of xanthones was affected by different concentrations of BA in medium. Shoot cultures grown at
higher BA concentrations contained more DGL than material grown in nature. The concentrations of other two xanthones were
lower in shoot cultures than in plants from nature. The radical scavenging activity of plant extracts and xanthones was investigated
by DPPH test. Samples from plants grown in nature showed the highest activity (IC50 = 0.26 mg ml−1), while the extracts of shoot cultures grown in media with higher concentrations of BA showed moderate activities (IC50 from 1.6 to 4.4 mg ml−1). 相似文献
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Nikolić Radomirka Mitić Nevena Nešković Mirjana 《Plant Cell, Tissue and Organ Culture》1997,48(1):67-69
Two newly selected Lotus corniculatus cultivars (Bokor and Zora), introduced recently as pasture legumes, were studied with respect to their in vitro regeneration capacity and field performance of R1 regenerates. Multiple buds were induced in callus tissues derived from apical buds, petioles, leaf and cotyledon explants. The rooted regenerates, acclimated in a greenhouse, were fertile. Seeds from the R1 generation were sown in the field and the plants found to be superior to controls in stem height and green mass production. 相似文献
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Radomirka Nikolić Nevena Mitić Rade Miletić Mirjana Nešković 《Journal of Plant Growth Regulation》2006,25(3):187-194
We determined the effects of zeatin (ZEA), isopentenyl adenine (2iP), kinetin (KIN), benzyladenine (BA), and thidiazuron (TDZ)
on seed germination, elongation of seedling shoots and roots, frequency of regeneration, and the number of regenerants per
seedling in Lotus corniculatus L. Sterilized seeds were cultured in vitro on Murashige and Skoog (1962) medium containing 3% sucrose, 0.7% agar, and various cytokinins (0, 0.08, 0.22, 0.35, 0.80, 2.20, and 3.50 μM). After 30
days, seedlings were transferred to cytokinin-free medium for another 60 days. All cytokinins stimulated the rate and percentage
of seed germination at least twofold in optimum concentrations; TDZ and ZEA were the most active, followed closely by BA,
whereas KIN and 2iP stimulated germination in higher concentrations only. Elongation of shoots and roots was strongly inhibited
at the lowest TDZ and BA concentrations, whereas ZEA, KIN, and 2iP exerted moderate, dose-dependent inhibition. The frequency
of regenerant-producing seeds was highest on ZEA and BA, whereas the greatest number of regenerants per seedling was found
on TDZ. It is concluded that the culture of seeds on cytokinin-containing media, followed by transfer to cytokinin-free medium,
is a suitable procedure for rapid production of a large number of uniform regenerants. The presumed role of particular cytokinins
is discussed. 相似文献
4.
Radomirka Nikolić Nevena Mitić Slavica Ninković Branka Vinterhalter Snežana Zdravković-Korać Mirjana Nešković 《Plant Growth Regulation》2010,62(2):181-188
Shoots of Lotus
corniculatus L., previously transformed with Agrobacterium
tumefaciens LBA4404/pTOK233, were grown in gibberellic acid (GA3)-containing media in an attempt to improve their growth and multiplication. Nodal stem segments of four poorly multiplying
clones, a clone with very good multiplication, and two non-transformed clones were incubated in media containing GA3 for 3 weeks, and then returned to a hormone-free medium for a further 3–5 subculture periods. Gibberellic acid increased
the number of axillary buds from one in controls to 2–13 shoots during the first 3 weeks of subculture in GA3-containing media. The multiplied buds, which apparently derived from additional axillaries, continued to multiply in hormone-free
medium, producing bunches of more than 50 shoots after 9 weeks. In addition, many nodal segments also produced callus tissues
at the basal end, or along the internode below the node, in which abundant shoot meristems formed de novo. Histological examination confirmed their origin via organogenesis. About 25% of regenerated shoots rooted spontaneously.
The application of auxins significantly improved rooting in more than 75% of all clones. Well-developed plantlets were produced
upon the transfer of rooted shoots to pots. No differences in responses to hormones were observed between LBA4404/pTOK233-transformed
clones and non-transformed clones, indicating that the reaction to GA3 was not the consequence of transformation events. The results point to a possible involvement of GA3 in lateral branching. They might also be recommended as a procedure suitable for increasing the production of transformed
plants in L. corniculatus. 相似文献
5.
Mitić N Dmitrović S Djordjević M Zdravković-Korać S Nikolić R Raspor M Djordjević T Maksimović V Zivković S Krstić-Milošević D Stanišić M Ninković S 《Journal of plant physiology》2012,169(12):1203-1211
We investigated Chenopodium murale transgenic hairy root in vitro culture system as a new tool for allelopathic assays. Transgenic hairy roots were induced by Agrobacterium rhizogenes A4M70GUS from roots, cotyledons, leaves, and internodes of C. murale seedlings. Roots were found to be the best target explants, providing transformation efficiency of up to 11.1%. Established hairy root clones differed in their morphology and growth potential. Molecular characterization of these clones was carried out by PCR, RT-PCR and histochemical GUS analyses. No differences in rol gene expression were observed. Liquid culture system of characterized hairy root clones was maintained for over 2 years. Six hairy root clones were selected for assaying the allelopathic effect of their growth medium against germination and seedling elongation of wheat and lettuce test plants. The inhibitory potential varied depending on the hairy root clone. Some transgenic clones showed significantly higher inhibition compared to wild-type roots. These results revealed that hairy roots as an independent system synthesize some bioactive substances with allelopathic activity and exude them into the growth medium. Concentrations of caffeic, ferulic and p-coumaric acids (0.07-2.85 μmol/L) identified by HPLC analysis in the growth media were at least 1000 times lower than the inhibitory active concentration (5 mmol/L) of pure grade phenolic acids, suggesting that they have a limited role in the allelopathic phenomena of C. murale. The presented hairy root system appears to be a suitable tool for further investigation of the potential and nature of root-mediated allelopathic interference of C. murale. 相似文献
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