WorldWideScience

Sample records for frequency plant regeneration

  1. High Frequency Plant Regeneration of Musa paradisiaca cv. Karibale Monthan

    Directory of Open Access Journals (Sweden)

    R. Shashi Kumar

    2015-06-01

    Full Text Available High frequency plant regeneration protocol has been standardized from banana cultivar Musa paradisiaca cv. Karibale Monthan, an endemic cultivar of Malnad region of Karnataka. The fruits are used as glomerular protective to solve kidney problems. To minimize the microbial contamination and to promote healthy growth, explants were treated with 70 % absolute alcohol for 6 min, 0.1 % Mercuric chloride for 10 min and 0.2 % for 10 min, 1 % Sodium hypochlorite for 15 min, 0.1 % Cefotaxime for 5 min and 0.05 % Gentamicin for 5 min. The high frequency shoot initiation (93.33 % was recorded at 5 mg/l BAP. The synergetic effect of BAP (4 to 6 mg/l, TDZ (0.1 to 1.2 mg/l and coconut water (0.1 to 0.9 ml/l induced multiple shoot buds and it was optimized at the concentration of 5 mg/l BAP, 0.5 mg/l TDZ and 0.5 ml/l coconut water with 15.90 ± 1.66 frequency of shoots per propagule. Supplementation of 1.0 mg/l IBA induced 5.33 ± 1.21 numbers of roots with a mean root length of 7.50 ± 1.87 roots. The 99% of plantlets with distinct roots and shoots were successfully acclimatized in the green house and transferred to the field to evaluate the agro-morphological variations. The weight of the bunch (kg, number of hands in a bunch, number of fingers in a hand, length of the finger (cm, girth of the finger (cm and girth of the pseudostem (cm exhibited by in vitro plants were higher than the in vivo plants.

  2. High frequency plant regeneration from mature seed- derived callus ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-15

    Dec 15, 2009 ... The overall plant regeneration rates of the examined cultivars ranged from 7.5 to ... MS basal salts and vitamins (Murashige and Skoog. 1962), 500 mg .... and BA examined, MS medium fortified with 5 mg l-1 of. 2,4-D and 0.5 ...

  3. Regeneration of transgenic citrus plants under non selective conditions results in high-frequency recovery of plants with silenced transgenes.

    Science.gov (United States)

    Domínguez, A; Fagoaga, C; Navarro, L; Moreno, P; Peña, L

    2002-06-01

    Insertion of foreign DNA into plant genomes frequently results in the recovery of transgenic plants with silenced transgenes. To investigate to what extent regeneration under selective conditions limits the recovery of transgenic plants showing gene silencing in woody species, Mexican lime [ Citrus aurantifolia (Christm.) Swing.] plants were transformed with the p25 coat protein gene of Citrus tristeza virus (CTV) with or without selection for nptII and uidA. Strikingly, more than 30% of the transgenic limes regenerated under non-selective conditions had silenced transgenes, and in all cases silencing affected all the three transgenes incorporated. These results indicate that the frequency of transgene silencing may be greatly underestimated when the rate of silencing is estimated from the number of regenerants obtained under selective conditions. To our knowledge, this is the first report in which the frequency of gene silencing after transformation has been quantified. When the integration pattern of T-DNA was analyzed in silenced and non-silenced lines, it was observed that inverted repeats as well as direct repeats and even single integrations were able to trigger gene silencing. Gene silencing has often been associated with the insertion of DNA sequences as inverted repeats. Interestingly, here, direct repeats and single-copy insertions were found in both silenced and non-silenced lines, suggesting that the presence of inverted-repeat T-DNAs and the subsequent formation of dsRNAs triggering gene silencing cannot account for all silencing events.

  4. The Effects of Weak Combined Magnetic Field on Cell Wall Regeneration and Frequency of Plant Protoplasts Fusion

    Science.gov (United States)

    Nedukha, Olena

    The major purpose of these experiments was to investigate plant protoplast fusion frequency and regeneration of a cell wall by protoplasts at weak combined magnetic field (CMF) with the frequency resonance to the cyclotron frequency of Mg2+, Ca2+ and K+ ions. The protoplasts were isolated from Nicotiana lumbaginifolia and N. silvestris leaf mesophyll and from callus tissues (Nicotiana tabacum and Glycine max). The special extra apparatus with ferromagnetic shield was used for estimate of CMF with the frequency resonance to the cyclotron frequency of Mg2+, Ca2+ and K+ ions. The fusion of protoplasts is realized by using of parent protoplasts isolated from one plant species, as well as from various plant species. Control samples were situated near the apparatus with CMF. The laser confocal microscopy was used for study of cell wall regeneration by single and fused protoplasts. The cytochemical methods with DAPI and calcofluor dye were also applied as the detectors for protoplast fusion and regeneration of cell wall. We have been established that CMF with frequency adjusted to the cyclotron frequency Mg2+ ions have shown the most positive influence on regeneration of cell wall by protoplasts. CMF adjusted to the cyclotron frequency of K+ ions very weakly affected on the frequency of protoplast fusion. Largest frequency of protoplasts fusion is noted in the CMF adjusted to the cyclotron frequency of Ca2+ in comparison with the control samples.

  5. High Frequency Plant Regeneration System from Transverse Thin Cell Layer Section of In vitro Derived ‘Nadia’ Ginger Microrhizome

    Directory of Open Access Journals (Sweden)

    Dikash Singh THINGBAIJAM

    2014-03-01

    Full Text Available An efficient and reproducible procedure is outlined for rapid in vitro multiplication of Zingiber officinale var. ‘Nadia’ through high frequency shoot proliferation from transverse thin cell layer (tTCL sections of in vitro derived microrhizome. In vitro derived microrhizome of size 500 μm in thickness was used as initial explants for induction of somatic embryos. Among the different phytohormones tested, tTCL explants shows maximum calli proliferation in medium containing 2 mg/L 2,4-Dichlorophenoxyacetic acid (88.30±0.11%. Reduced concentration of 2,4 Dichlorophenoxyacetic acid was supplemented with different cytokinins for regeneration of callus. Among the different medium tested, optimum redifferentiation of somatic embryos were observed in medium containing 0.2 mg/L 2,4 Dichlorophenoxyacetic acid and 6.0 mg/L BAP (141.08±0.25. Clump of regenerated plantlets were further subculture and transfer into microrhizome inducing medium containing high sucrose concentration (8%. Plantlets with well developed microrhizome were successfully acclimatized and eventually transferred to the field. The application of studying embryo section for regeneration of plants might be useful alternative to ginger improvement programme. Histological analysis showed formation of somatic embryos and regenerated adventitious shoot.

  6. High-frequency plant regeneration through cyclic secondary somatic embryogenesis in black pepper (Piper nigrum L.).

    Science.gov (United States)

    Nair, R Ramakrishnan; Dutta Gupta, S

    2006-01-01

    A high-frequency plantlet regeneration protocol was developed for black pepper (Piper nigrum L.) through cyclic secondary somatic embryogenesis. Secondary embryos formed from the radicular end of the primary somatic embryos which were originally derived from micropylar tissues of germinating seeds on growth regulator-free SH medium in the absence of light. The process of secondary embryogenesis continued in a cyclic manner from the root pole of newly formed embryos resulting in clumps of somatic embryos. Strength of the medium and sucrose concentration influenced the process of secondary embryogenesis and fresh weight of somatic embryo clumps. Full-strength SH medium supplemented with 1.5% sucrose produced significantly higher fresh weight and numbers of secondary somatic embryos while 3.0 and 4.5% sucrose in the medium favored further development of proliferated embryos into plantlets. Ontogeny of secondary embryos was established by histological analysis. Secondary embryogenic potential was influenced by the developmental stage of the explanted somatic embryo and stages up to "torpedo" were more suitable. A single-flask system was standardized for proliferation, maturation, germination and conversion of secondary somatic embryos in suspension cultures. The system of cyclic secondary somatic embryogenesis in black pepper described here represents a permanent source of embryogenic material that can be used for genetic manipulations of this crop species.

  7. Establishment of high frequency shoot regeneration system in Himalayan poplar (Populus ciliata Wall. ex Royle) from petiole explants using Thidiazuron cytokinin as plant growth regulator

    Institute of Scientific and Technical Information of China (English)

    G Aggarwal; A Gaur; D K Srivastava

    2015-01-01

    Populus species are important resources for industry and in scientific study on biological and agricul-tural systems. Our objective was to enhance the frequency of plant regeneration in Himalayan poplar (Populus ciliata wall. ex Royle). The effect of TDZ alone and in combi-nation with adenine and NAA was studied on the regen-eration potential of petiole explants. The explants were excised from Himalayan poplar plants grown in glass-houses. After surface sterilization the explants were cul-tured on shoot induction medium. High percentage shoot regeneration (86%) was recorded on MS medium sup-plemented with 0.004 mg L-1 TDZ and 79.7 mg L-1 adenine. The regenerated shoots for elongation and multi-plication were transferred to MS ? 0.5 mg L-1 BAP ? 0.2 mg L-1 IAA ? 0.3 mg L-1 GA3. Root re-generation from shoots developed in vitro was observed on MS medium supplemented with 0.10 mg L-1 IBA. Hi-malayan poplar plantlets could be produced within 2 months after acclimatization in a sterile mixture of sand and soil. We developed a high efficiency plant regeneration protocol from petiole explants of P. ciliata.

  8. High frequency somatic embryogenesis and plant regeneration from zygotic embryo-derived callus cultures of three Allium species

    NARCIS (Netherlands)

    Valk, P. van der; Scholten, O.E.; Verstappen, F.; Jansen, R.C.; Dons, J.J.M.

    1992-01-01

    The plant regeneration ability of zygotic embryo-derived callus cultures was studied for 12 A. cepa varieties and accessions, two A. fistulosum varieties, one A. fistulosum × A. cepa interspecific hybrid and two A. porrum varieties. Compact embryogenic callus was induced on Murashige and Skoog (MS)

  9. High frequency somatic embryogenesis and plant regeneration from zygotic embryo-derived callus cultures of three Allium species

    NARCIS (Netherlands)

    Valk, P. van der; Scholten, O.E.; Verstappen, F.; Jansen, R.C.; Dons, J.J.M.

    1992-01-01

    The plant regeneration ability of zygotic embryo-derived callus cultures was studied for 12 A. cepa varieties and accessions, two A. fistulosum varieties, one A. fistulosum × A. cepa interspecific hybrid and two A. porrum varieties. Compact embryogenic callus was induced on Murashige and Skoog (MS)

  10. High Frequency Plant Regeneration System from Transverse Thin Cell Layer Section of In vitro Derived ‘Nadia’ Ginger Microrhizome

    Directory of Open Access Journals (Sweden)

    Dikash Singh THINGBAIJAM

    2014-03-01

    Full Text Available An efficient and reproducible procedure is outlined for rapid in vitro multiplication of Zingiber officinale var. ‘Nadia’ through high frequency shoot proliferation from transverse thin cell layer (tTCL sections of in vitro derived microrhizome. In vitro derived microrhizome of size 500 μm in thickness was used as initial explants for induction of somatic embryos. Among the different phytohormones tested, tTCL explants shows maximum calli proliferation in medium containing 2 mg/L 2,4-Dichlorophenoxyacetic acid (88.30±0.11%. Reduced concentration of 2,4 Dichlorophenoxyacetic acid was supplemented with different cytokinins for regeneration of callus. Among the different medium tested, optimum redifferentiation of somatic embryos were observed in medium containing 0.2 mg/L 2,4 Dichlorophenoxyacetic acid and 6.0 mg/L BAP (141.08±0.25. Clump of regenerated plantlets were further subculture and transfer into microrhizome inducing medium containing high sucrose concentration (8%. Plantlets with well developed microrhizome were successfully acclimatized and eventually transferred to the field. The application of studying embryo section for regeneration of plants might be useful alternative to ginger improvement programme. Histological analysis showed formation of somatic embryos and regenerated adventitious shoot.

  11. High frequency in vitro plantlet regeneration and antioxidant activity ofEnicostema axillare (Lam.)Raynal ssp. littoralis (Blume)Raynal:An important medicinal plant

    Institute of Scientific and Technical Information of China (English)

    Kousalya Loganathan; VNarmatha Bai

    2014-01-01

    Objective:To develop a method for high frequency plantlets regeneration protocol forEnicostema axillare(Lam.)Raynal ssp.littoralis(Blume)Raynal(E. axillare) without intermediate callus phase and to determine the content and correlation of phenolic compounds and their antioxidant activity of both the plants derived from nature and nodal culture byDPPH assay.Methods:The nodal explants were cultured onMS basal medium fortified with different concentration of various growth regulators such asBAP,KIN,TDZ and2iP(0.5-2 mg/L) individually and in combinations with or withoutGA3 for shoot bud induction and multiplication.Total phenol and flavonoid content was determined in both plants from nature and nodal culture and antioxidant activity was determined byDPPH assay.Results:The highest number of multiple shoot(108.00±3.55 shoots/explants) was obtained onMS medium supplemented withBAP(2 mg/L) in combination withKIN (0.5 mg/L) andGA3(2 mg/L).Rooting was optimized on half-strengthMS medium supplemented withIAA(0.5 mg/L).The rooted plantlets were transferred to paper cups containing vermiculite and hardening was successfully attained with75% survival.Among the four extract of methanol and water extract from both the plantlet from nature and nodal culture, the concentration of flavonoid was found to be higher in methanol extract of the plants from nature(146.57±1.68 mg rutin/g extract) and phenol content was higher in the water extract of plant from nature(52.53±1.67 mgGAE /g extract).The radical scavenging activity of four extracts.Methanol extract of plant grown in nature showed the highest radical scavenging activity(IC50 =87.10 μg/mL) was investigated byDPPH test.Conculsion:The present study not only enables reinforcement of wild plant populations usingex situ growth of individuals, but it also helps for high scale production of plantlets.A high correlation between antioxidant capacities and their total phenolic contents indicated that flavonoid compounds were a major

  12. The effect of dehydration on plant regeneration and some physiology characters in rice calli

    Institute of Scientific and Technical Information of China (English)

    ZHAOChengzhang; WULianbin; YANGChangdeng; QIXiufang

    1997-01-01

    The plant regeneration frequencies of calli from plant tissue and cell culture, especially that of the calli from rice tissue culture and rice anther culture, and that of the foreign-DNA-transfor-matlon-derived rice calli is very low (usually 10-15%). It is therefor very important to improve the plant regeneration frequency of rice calli.

  13. Regeneration of Stevia Plant Through Callus Culture

    Science.gov (United States)

    Patel, R. M.; Shah, R. R.

    2009-01-01

    Stevia rebaudiana Bertoni that conventionally propagated by seed or by cuttings or clump division which has a limitation of quality and quantity seed material. In present study, callus culture technique was tried to achieve rapid plant multiplication for quality seed material. Callus induction and multiplication medium was standardized from nodal as well as leaf sagments. It is possible to maintain callus on Murashige and Skoog medium supplemented with 6-benzyl amino purine and naphthalene acetic acid. Maximum callus induction was obtained on Murashige and Skoog medium incorporated with 6-benzyl amino purine (2.0-3.0 mg/l) and naphthalene acetic acid (2.0 mg/l) treatments. However, Murashige and Skoog medium containing 2.0 mg/l 6-benzyl amino purine+2.0 mg/l naphthalene acetic acid was found to be the best for callus induction. Higher regeneration frequency was noticed with Murashige and Skoog medium supplemented with 2.0 mg/l 6-benzyl amino purine+0.2 mg/l naphthalene acetic acid. Regenerated plants were rooted better on ¼ Murashige and Skoog strength supplemented with 0.1 mg/l indole-3-butyric acid. The rooted plantlets were hardened successfully in tera care medium with 63 per cent survival rate. The developed protocol can be utilized for mass production of true to type planting material on large scale independent of season, i.e. external environmental conditions. PMID:20177455

  14. In Vitro Regeneration of Endangered Medicinal Plant Heliotropium kotschyi (Ramram).

    Science.gov (United States)

    Sadeq, Manal Ahmed; Pathak, Malabika Roy; Salih, Ahmed Ali; Abido, Mohammed; Abahussain, Asma

    2016-01-01

    Heliotropium kotschyi (Ramram) is an important endangered medicinal plant distributed in the Kingdom of Bahrain. Plant tissue culture technique is applied for ex situ conservation study. Nodal stem segments are cultured in modified MS media supplemented with various combination and concentration of plant growth regulators (PGRs). Plants are regenerated via shoot organogenesis from the nodal meristems. Plants are regenerated in three different steps: initial shoot development, shoot multiplication, and rooting. After 4 weeks of culture, 100 % explants respond to shoot initiation on the medium containing 8.88 μM BAP and 5.71 μM IAA. The highest frequency of shoot regeneration is observed in the same media after second subculture of shoots. The highest rooting frequency is observed in the presence of 2.85 μM IAA. After root development, the plantlets are transferred to pots filled with soil and 60 % of plants survived after 45 days. This plant regeneration protocol is of great value for rapid desert plant propagation program.

  15. SOMATIC EMBRYOGENESIS AND PLANT REGENERATION FROM ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    Florets were excised from panicles after six days of artificial crossing, and cultured in. Murashige ... were regenerated into plantlets in half MS medium without plant growth regulators. Plantlets of .... 13 cm diameter, containing light soils in the.

  16. Adventitious shoots induction and plant regeneration from ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-07-08

    Jul 8, 2015 ... vitro plant regeneration for three watermelon cultivars. To achieve optimal .... watermelon genotypes gave shoot differentiation fre- quencies of 8.33-83.33% on MB5 .... They thought cells competent for shoot formation are not ...

  17. Plant Regeneration of Sweet Potato via Somatic Embryogenesis from Different Explants

    Institute of Scientific and Technical Information of China (English)

    Ling ZHANG; Hongxuan XU; Baifu QIN; Zhihua LIA0; Min CHEN; Chunxian YANG; Yufan FU; Qitang ZHANG

    2012-01-01

    [Objective] This study aimed to regenerate plants of sweet potato (Ipomoea batatas) cultivar Xushu22 via somatic embryogenesis, using leaf and shoot apex as explants. [Method] The leaf and shoot apex of Xushu 22 were separately cultured on MSB medium and MSD medium. The induced embryogenic calluses were then cultured on MS medium. The regeneration frequency of leaf and shoot apex ex- plants were respectively calculated. [Result] The average frequency of leaf explants developing somatic callus was 95.69% compared to 30.56% in case of shoot apex explants. There were different types of morphogenic structures in the process of so- matic embryo development. Leaf explants gave a high regeneration frequency to 60.61%, while the regeneration frequency of shoot apices was 22%. In addition, no morphological variations were observed in the regeneration plants. [Conclusion] Leaf explant was better than shoot apices in plant regeneration of Xushu22 via somatic embryogenesis.

  18. The Application of TDZ in Enhancing Regeneration of Transgenic Plants

    Institute of Scientific and Technical Information of China (English)

    H.Y. Jia; B. Zhao; X.D. Wang

    2007-01-01

    @@ At present, transgenic plants are globally grown. Availability of a reliable regeneration system predominantly from a single transformed cell is the prerequisites for gene transfer, but regeneration is still a key problem (Wenzel, 2006).

  19. High frequency shoot regeneration of Sterculia urens Roxb. an ...

    African Journals Online (AJOL)

    SERVER

    2007-07-18

    Jul 18, 2007 ... ingredient in the preparation of emulsions, lotions, denture fixative powders, bulk ... the wood leads to borer attack, which may prove fatal. Unscientific .... cytokinin had a significant effect on the frequency of shoot regeneration ...

  20. Regeneration of Transgenic Soybean (Glycine max) Plants from Electroporated Protoplasts.

    Science.gov (United States)

    Dhir, S K; Dhir, S; Savka, M A; Belanger, F; Kriz, A L; Farrand, S K; Widholm, J M

    1992-05-01

    Transgenic soybean (Glycine max [L.] Merr.) plants were regenerated from calli derived from protoplasts electroporated with plasmid DNA-carrying genes for a selectable marker, neomycin phosphotransferase (NPTII), under the control of the cauliflower mosaic virus 35-Svedberg unit promoter, linked with a nonselectable mannityl opine synthesis marker. Following electroporation and culture, the protoplast-derived colonies were subjected to kanamycin selection (50 micrograms per milliliter) beginning on day 15 for 6 weeks. Approximately, 370 to 460 resistant colonies were recovered from 1 x 10(6) electroporated protoplasts, giving an absolute transformation frequency of 3.7 to 4.6 x 10(-4). More than 80% of the kanamycin-resistant colonies showed NPTII activity, and about 90% of these also synthesized opines. This indicates that the linked marker genes were co-introduced and co-expressed at a very high frequency. Plants were regenerated from the transformed cell lines. Southern blot analysis of the transformed callus and leaf DNA demonstrated the integration of both genes. Single-plant assays performed with different plant parts showed that both shoot and root tissues express NPTII activity and accumulate opines. Experiments with NPTII and mannityl opine synthesis marker genes on separate plasmids resulted in a co-expression rate of 66%. These results indicate that electroporation can be used to introduce both linked and unlinked genes into the soybean to produce transformed plants.

  1. High frequency in vitro plantlet regeneration and antioxidant activity of Enicostema axillare(Lam. Raynal ssp. littoralis (Blume Raynal: An important medicinal plant

    Directory of Open Access Journals (Sweden)

    Kousalya Loganathan

    2014-09-01

    Conclusion: The present study not only enables reinforcement of wild plant populations using ex situ growth of individuals, but it also helps for high scale production of plantlets. A high correlation between antioxidant capacities and their total phenolic contents indicated that flavonoid compounds were a major contributor of antioxidant activity of both plants grown from nature and nodal culture.

  2. Plant regeneration of Alstroemeria in vitro

    Directory of Open Access Journals (Sweden)

    Eleonora Gabryszewska

    2013-12-01

    Full Text Available The regenerative ability of explants from various organs of Alstroemeria plants was investigated. Rhizome apical and axillary tips cultured on the Murashige and Skoog medium with BA - 2. mgl-1 and NAA - 0,5 mgl-1 were the best among the tissue tested as initial explants. Five weeks after isolation the rhizome with 1-4 upright growing shoots were obtained. The types of rhizome explants influenced development and growth of lateral rhizomes and upright growing shoots. There were no significant differences in number of roots formed on various kind of rhizome explants. Rooting was strongly influenced by NAA. Subapical segments of vegetative stem, segments of flower pedicels and parts of ovary did not regenerate rhizome or roots but occasionally callus was formed on the medium with kinetin - 2 mgl-1 and NAA - 2 mgl-1. Segments excised from vegetative stem sporadically developed roots on the medium with NAA or IBA in concentrations 3 and 9 mgl-1.

  3. Plant regeneration and genetic transformation in Jatropha

    KAUST Repository

    Sujatha, M.

    2012-07-01

    Jatropha curcas, a non-edible oil bearing species with multiple uses, and considerable economic potential is emerging as a potential biofuel plant. The limited knowledge of this species, low and inconsistent yields, the narrow genetic variability, and vulnerability to insects and diseases are major constraints in successful cultivation of Jatropha as a biofuel crop. Hence, genetic improvement of Jatropha is essential by conventional and modern biotechnological tools to use as a viable alternative source of bio-diesel. Realising its potential as a bio-energy crop, in vitro regeneration methods have been established to meet the demand of large scale supply of superior clones, and also as a prelude for genetic improvement of the species through transgenic approaches. In this chapter, an overview of in vitro tissue culture and genetic transformation of Jatropha is discussed. © 2013 Springer Science+Business Media Dordrecht. All rights are reserved.

  4. Regenerator Operation at Very High Frequencies for Microcryocoolers

    Science.gov (United States)

    Radebaugh, Ray; O'Gallagher, Agnes

    2006-04-01

    The size of Stirling and Stirling-type pulse tube cryocoolers is dominated by the size of the pressure oscillator. Such cryocoolers typically operate at frequencies up to about 60 Hz for cold-end temperatures above about 60 K. Higher operating frequencies would allow the size and mass of the pressure oscillator to be reduced for a given power input. However, simply increasing the operating frequency leads to large losses in the regenerator. The simple analytical equations derived here show how the right combination of frequency and pressure, along with optimized regenerator geometry, can lead to successful regenerator operation at frequencies up to 1 kHz. Efficient regenerator operation at such high frequencies is possible only with pressures of about 5 to 8 MPa and with very small hydraulic diameters and lengths. Other geometrical parameters must also be optimized for such conditions. The analytical equations are used to provide guidance to the right combination of parameters. We give example numerical calculations with REGEN3.2 in the paper for 60 Hz, 400 Hz, and 1000 Hz operation of optimized screen regenerators and show that the coefficient of performance at 400 Hz and 1000 Hz is about 78 % and 68 %, respectively, of that for 60 Hz when an average pressure of 7 MPa is used with the higher frequency, compared with 2.5 MPa for 60 Hz operation. The 1000 Hz coefficient of performance for parallel tubes is about the same as that of the screen geometry at 60 Hz. The compressor and cold-end swept volumes are reduced by a factor of 47 at 1000 Hz, compared with the 60 Hz case for the same input acoustic power, which can enable the development of microcryocoolers for MEMS applications.

  5. Direct Adventitious Bud Induction and Plant Regeneration of Rosa hybrida Samantha

    Institute of Scientific and Technical Information of China (English)

    GAO Li-ping; BAO Man-zhu

    2005-01-01

    Effect of explant, site of leaflet, induction period in the dark and combinations of plant growth regulators on direct adventitious bud induction and plant regeneration of Rosa hybrida Samantha was investigated. The results showed that after an induction period of 8 d on MS medium with 1.5 mg L-1 TDZ and 0.05 mg L-1 NAA in the dark and a subculture on MS medium with 0.5 mg L-1 BA and 0.01 mg L-1 NAA under light, the best plant regeneration was obtained and the regeneration frequencies of leaflets and petioles were 51.8 and 10% respectively. There was no significant difference in regeneration ability between leaflets at different sites of the compound leaves, longer time of induction in the dark or high concentration of auxin would cause callus formation, which was disadvantageous for shoot regeneration, and the regeneration frequency was significantly reduced. This regeneration system could be applied for genetic transformation of this cultivar in the future.

  6. Callus induction and plant regeneration from mature zygotic embryos of a tetraploid Alstroemeria (A. pelegrina × A. psittacina).

    Science.gov (United States)

    Hutchinson, M J; Tsujita, J M; Saxena, P K

    1994-12-01

    A simple procedure was developed to induce callus growth and whole plant regeneration for a tetraploid cultivar of Alstroemeria. The callus, induced from mature zygotic embryos cultured on a medium supplemented with 20 μM kinetin with 10 or 20 μM NAA, could be maintained for one year without any loss of regeneration potential. Maximum frequency of regeneration (40%) was obtained with calli maintained on the medium containing 20 μM kinetin and 20 μM NAA. Whole plant regeneration occurred via somatic embryogenesis in the absence of growth regulators and the plantlets grew to maturity and flowered in the greenhouse conditions.

  7. Regeneration in plants and animals: dedifferentiation, transdifferentiation, or just differentiation?

    Science.gov (United States)

    Sugimoto, Kaoru; Gordon, Sean P; Meyerowitz, Elliot M

    2011-04-01

    The textbooks and literature of plant biology indicate that plant cells are totipotent, and that regeneration occurs via dedifferentiation, by which the cell and its descendents recapitulate earlier stages of development. However, recent work on the generation of callus, a presumed undifferentiated or dedifferentiated and disorganized cellular mass, indicates that the cells of callus are neither, and that callus forms predominantly from a pre-existing population of stem cells. Recent work in animal regeneration, for example in salamander limbs, also indicates that previous assumptions about the extent of dedifferentiation and pluripotency in animals are in need of critical reassessment. We review here some of these data, compare plant and animal regeneration, and argue that the importance of dedifferentiation and plasticity in regenerating systems is due for reevaluation. Copyright © 2010 Elsevier Ltd. All rights reserved.

  8. Plant Regeneration and Genetic Transformation in Eggplant ...

    African Journals Online (AJOL)

    Dr Harmander Gill

    2014-02-05

    Feb 5, 2014 ... 2School of Agricultural Biotechnology, Punjab Agricultural University, Ludhiana, 141004 India. Accepted 5 ... media affect its regeneration potential (Kantharajah and .... Rogor and Kitazin in relation to their concentrations also.

  9. Plant regeneration from protoplasts of hydroxyproline resistant cell line in Onobrychis viciaefolia

    Institute of Scientific and Technical Information of China (English)

    XUZIQIN; JINGFENJIA

    1995-01-01

    An efficient protocol for plant regeneration from protoplasts of hydroxyproline(HYP)resistant cell line of Onobrychis viciaefolia was established.In SH medium supplemented with 1mg/L2,4-dichlorophenoxy-acetic acid(2,4-D),0.5mg/L kinetin(KT)and 0.2mg/L naphthalene acetic acid(NAA),the division frequency of protoplastderived cells reached up to over 60%,and microcalli were obtained in 5-6wk.Upon transferring them on agar solidified MS medium plus 2mg/L indole-3-acetic acid (IAA),shoots were induced.After cultivating them on MS medium with or without IAA,roots were regenerated.Chromosome number of all protoplast-regenerated plants examined were normal(2n=28).The protoplast-derived calli and plants grew vigorously on the medium containing 10 mmol/L HYP.

  10. Efficient culture protocol for plant regeneration from cotyledonary petiole explants of Jatropha curcas L.

    Directory of Open Access Journals (Sweden)

    Ying Liu

    2016-09-01

    Full Text Available A high-frequency and reproducible protocol for induction of adventitious shoot buds and plant regeneration from cotyledonary petiole explants of Jatropha curcas L. has been developed. The cotyledonary petiole explants of J. curcas cultured directly on medium supplemented with thidiazuron (TDZ induce regeneration of poor quality shoot buds that have a low regeneration frequency. However, treating the explants with high concentrations (10–60 mg/L of TDZ solution for certain time periods (5–80 min significantly increased the regeneration frequency and improved the quality of the regenerated shoot buds. The best shoot buds induction (88.42% and number of shoot buds (12.67 per explant were observed when in vitro explants were treated with 20 mg/L TDZ solution for 20 min before being transferred on hormone-free medium after 30 days. Regeneration was also influenced by the orientation (horizontal or vertical of the explants on the medium, and by the origin of the cotyledonary petioles (in vitro or in vivo used for the preparation of explants. We performed subsequent experiments for elongation and rooting of the regenerated shoot buds. Addition of L-arginine to the medium was conducive to the elongation of the shoot buds. A concentration of 7.5 mg/L L-arginine yielded the best results. The elongated shoots could initiate roots to become intact plantlets in half-strength Murashige and Skoog medium containing 0.1 mg/L indole-3-butyric acid. After acclimatization, these plantlets could be transplanted to the soil and the growth was normal. Therefore, application of the methods described here helped to increase plant regeneration efficiency.

  11. Transformation and regeneration of the holoparasitic plant Phelipanche aegyptiaca

    Directory of Open Access Journals (Sweden)

    Fernández-Aparicio Mónica

    2011-11-01

    Full Text Available Abstract Background Transformation and subsequent regeneration of holoparasitic plants has never been reported, in part due to challenges in developing transformation protocols, but also because regeneration of obligate parasites is difficult since their survival depends completely on successful haustorium penetration of a host and the formation of vascular connections. The recent completion of a massive transcriptome sequencing project (the Parasitic Plant Genome Project will fuel the use of genomic tools for studies on parasitic plants. A reliable system for holoparasite transformation is needed to realize the full value of this resource for reverse genetics and functional genomics studies. Results Here we demonstrate that transformation of Phelipanche aegyptiaca is achieved by infection of 3 month-old in vitro grown P. aegyptiaca calli with Agrobacterium rhizogenes harboring the yellow fluorescent protein (YFP. Four months later, YFP-positive regenerated calli were inoculated onto tomato plants growing in a minirhizotron system. Eight days after inoculation, transgenic parasite tissue formed lateral haustoria that penetrated the host and could be visualized under UV illumination through intact host root tissue. YFP-positive shoot buds were observed one month after inoculation. Conclusions This work constitutes a breakthrough in holoparasitic plant research methods. The method described here is a robust system for transformation and regeneration of a holoparasitic plant and will facilitate research on unique parasitic plant capabilities such as host plant recognition, haustorial formation, penetration and vascular connection.

  12. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

    Institute of Scientific and Technical Information of China (English)

    吕德扬; 曹学远; 唐顺学; 田霞

    2000-01-01

    Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of trans-genie plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.

  13. Regeneration of foreign genes co-transformed plants of Medicago sativa L by Agrobacterium rhizogenes

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Gene encoding sulphur amino acid-rich protein (HNP) and rol genes were transferred into Medicago sativa L (alfalfa) mediated by Agrobacterium tumafeciens. Regeneration of transgenic plants was induced successfully from hairy root tissue of cotyledon in alfalfa. Cotyledon tissues were an ideally transformed recipient. There was a negative correlation between age of hairy roots and embryogenesis frequency in alfalfa. Production of co-transformed plants with greater yield and super quality was important for development of new alfalfa varieties.

  14. Plants regenerated from mesophyll protoplasts of white mulberry

    Institute of Scientific and Technical Information of China (English)

    WEIZHIMING; ZHIHONGXU; 等

    1994-01-01

    Morus alba(white mulberry) mesophyll protoplasts were isolated from leaves of 30-45 day old sterile shoots,with protoplast yields of 2.5×107 g-1/F.W.after purification.The protoplasts were cultured in a modified K8P liquid medium containing 0.2mg/L 2,4-(2,4-Dichlorophenoxy acetic acid),1mg/L NAA(Naphthyl acetic acid) and 0.5mg/L BA(6-benzylaminopurine).A low plating density(5×104/ml) proved to be favourable to the division of protoplast-derived cells.The first division occurred 4 days after culture,and the division frequency reached 24% at 10 days.A number of cell colonies and microcalli formed in 6 weeks.The microcalli were transferred onto MSB medium with 0.5mg/L NAA and 0.5mg/L BA for further proliferation.Shoot formation was initiated when the calli of 3-4 mm in size were transferred onto MSB differentiation medium with 0.1mg/L NAA and 1mg/L BA.The frequency of shoot formation was 35%.The shoots of 4-5 cm in height were excised from the callus and rooted on half strength MS medium with 0.5 mg/L IBA and 0.1 mg/L BA.After transplantation into pots,the regenerated plants grew vigorously in the phytotron.

  15. Vegetative Regeneration Capacities of Five Ornamental Plant Invaders After Shredding

    Science.gov (United States)

    Monty, Arnaud; Eugène, Marie; Mahy, Grégory

    2015-02-01

    Vegetation management often involves shredding to dispose of cut plant material or to destroy the vegetation itself. In the case of invasive plants, this can represent an environmental risk if the shredded material exhibits vegetative regeneration capacities. We tested the effect of shredding on aboveground and below-ground vegetative material of five ornamental widespread invaders in Western Europe that are likely to be managed by cutting and shredding techniques: Buddleja davidii (butterfly bush, Scrophulariaceae), Fallopia japonica (Japanese knotweed, Polygonaceae), Spiraea × billardii Hérincq (Billard's bridewort, Rosaceae), Solidago gigantea (giant goldenrod, Asteraceae), and Rhus typhina L. (staghorn sumac, Anacardiaceae). We looked at signs of vegetative regeneration and biomass production, and analyzed the data with respect to the season of plant cutting (spring vs summer), the type of plant material (aboveground vs below-ground), and the shredding treatment (shredded vs control). All species were capable of vegetative regeneration, especially the below-ground material. We found differences among species, but the regeneration potential was generally still present after shredding despite a reduction of growth rates. Although it should not be excluded in all cases (e.g., destruction of giant goldenrod and staghorn sumac aboveground material), the use of a shredder to destroy woody alien plant material cannot be considered as a general management option without significant environmental risk.

  16. Experiences in construction of liquid manure regeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Eichler, D.

    1981-08-01

    We have to divide the main problems of the development of the liquid manure regeneration into three steps of procedure, especially the regeneration in pig production units up to 200,000 animal places: 1. solid-liquid-separation, 2. microbiological processing, 3. bio-sludge processing. The aim of the processing method is the production: of a chargeable solid matter with 30% dried matter especially for fertilization; of a cleaned waste water for the using in sprinkling irrigation systems or ponds or usual sewage treatment plants of a proteinaceous dried bio-matter with about 50% raw protein, that will be used after an elucidation of the conditions as a special compost in the champignon production, as aggregates for fish food, as primary material for other feed. The arrangement and structure of such a liquid manure regeneration plant will be illustrated by some pictures and tables.

  17. Rapid plant regeneration from cotton(Gossypium hirsutum L.)

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A simple and rapid regeneration method of cotton (Gossypium hirsutum L.cv.Xinluzao 4) is described.The proper use of phytohormone KT and IBA validly promoted the survival rate of test-tube plants and shortened the period of culture in combination with the techniques of micro-propagation and graft.

  18. Externally imposed electric field enhances plant root tip regeneration

    Science.gov (United States)

    Kral, Nicolas; Hanna Ougolnikova, Alexandra

    2016-01-01

    Abstract In plants, shoot and root regeneration can be induced in the distinctive conditions of tissue culture (in vitro) but is also observed in intact individuals (in planta) recovering from tissue damage. Roots, for example, can regenerate their fully excised meristems in planta, even in mutants with impaired apical stem cell niches. Unfortunately, to date a comprehensive understanding of regeneration in plants is still missing. Here, we provide evidence that an imposed electric field can perturb apical root regeneration in Arabidopsis. Crucially, we explored both spatial and temporal competences of the stump to respond to electrical stimulation, by varying respectively the position of the cut and the time interval between excision and stimulation. Our data indicate that a brief pulse of an electric field parallel to the root is sufficient to increase by up to two‐fold the probability of its regeneration, and to perturb the local distribution of the hormone auxin, as well as cell division regulation. Remarkably, the orientation of the root towards the anode or the cathode is shown to play a role. PMID:27606066

  19. Plant regeneration from protoplasts of Gentiana straminea Maxim

    Directory of Open Access Journals (Sweden)

    Shi Guomin

    2016-04-01

    Full Text Available A protocol is described for plant regeneration from protoplasts of Gentiana straminea Maxim. via somatic embryogenesis. Protoplasts were isolated from embryogenic calli in an enzyme solution composed of 2% Cellulase Onozuka R-10, 0.5% Macerozyme R-10, 0.5% Hemicellulase, and 0.5 M sorbitol with a yield of 3.0 × 106 protoplasts per gram of fresh weight. Liquid, solid-liquid double layer (sLD and agar-pool (aPL culture systems were used for protoplast culture. The aPL culture was the only method that produced embryogenic, regenerative calli. With aPL culture, the highest frequencies of protoplast cell division and colony formation were 39.6% and 16.9%, respectively, on MS medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D and 0.5 mg/L N6-benzylaminopurine (BA. Microcalli were transferred to solid MS medium containing a reduced concentration of 2,4-D (0.5 mg/L to promote the formation of embryogenic calli. Somatic embryos developed into plantlets on MS medium supplemented with 2 mg/L BA at a rate of 43.7%.

  20. Rapid plant regeneration of chrysanthemum (Chrysanthemum ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-04

    May 4, 2009 ... Satisfactory rooting response was obtained in half strength MS media supplemented ... Rapid clonal plant propagation in vitro can be obtained through bud or ..... D, Galgy R (1978). Multiplication of vegetative dela Cannal a.

  1. Plant regeneration from callus culture of vetiver (Vetiveria zizanioides Nash

    Directory of Open Access Journals (Sweden)

    Somporn Prasertsongskun

    2003-09-01

    Full Text Available The present research aimed to establish cell suspension culture of vetiver (Vetiveria zizanioides Nash from Surat Thani germplasm source and efficient plant regeneration from callus derived from such cultures. Cell suspension cultures were established from calli derived from inflorescence of vetiver. Optimum cell proliferation occurred in liquid N6 medium supplemented with 10 μM 2,4-dichlorophenoxyacetic acid (2,4-D and 10 mM proline. The cell suspension formed the highest small colonies when plated on solid MS medium containing 0.45 μM 2,4-D. After subsequent transfer to regeneration medium (MS free medium 65% of plantlets were obtained.

  2. Somatic embryogenesis and plant regeneration of Capsicum baccatum L.

    Directory of Open Access Journals (Sweden)

    Peddaboina Venkataiah

    2016-06-01

    Full Text Available A plant regeneration protocol via somatic embryogenesis was achieved in cotyledon and leaf explants of Capsicum baccatum, when cultured on MS medium supplemented with various concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D, 0.5–5.0 mg l−1 in combination with Kinetin (Kn, 0.5 mg l−1 and 3% sucrose. Various stages were observed during the development of somatic embryos, including globular, heart, and torpedo-stages. Torpedo stage embryos were separated from the explants and subcultured on medium supplemented with various concentrations of different plant growth regulators for maturation. Maximum percentage (55% of somatic embryo germination and plantlet formation was found at 1.0 mg l−1 BA. Finally, about 68% of plantlets were successfully established under field conditions. The regenerated plants were morphologically normal, fertile and able to set viable seeds.

  3. Guard cell protoplasts: isolation, culture, and regeneration of plants.

    Science.gov (United States)

    Tallman, Gary

    2006-01-01

    Guard cell protoplasts have been used extensively in short-term experiments designed to elucidate the signal transduction mechanisms that regulate stomatal movements. The utility of uard cell protoplasts for other types of longer-term signal transduction experiments is just now being realized. Because highly purified, primary isolates of guard cell protoplasts are synchronous initially, they are uniform in their responses to changes in culture conditions. Such isolates have demonstrated potential to reveal mechanisms that underlie hormonal signalling for plant cell survival, cell cycle re-entry, reprogramming of genes during dedifferentiation to an embryogenic state, and plant cell thermotolerance. Plants have been regenerated from cultured guard cell protoplasts of two species: Nicotiana glauca (Graham), tree tobacco, and Beta vulgaris, sugar beet. Plants genetically engineered for herbicide tolerance have been regenerated from cultured guard cell protoplasts of B. vulgaris. The method for isolating, culturing, and regenerating plants from guard cell protoplasts of N. glauca is described here. A recently developed procedure for large-scale isolation of these cells from as many as nine leaves per experiment is described. Using this protocol, yields of 1.5-2 x 10(7) per isolate may be obtained. Such yields are sufficient for standard methods of molecular, biochemical, and proteomic analysis.

  4. Two ways of plant regeneration from immature cotyledons of pea

    Directory of Open Access Journals (Sweden)

    Anna Nadolska-Orczyk

    2014-01-01

    Full Text Available Two different systems of plant regeneration via organogenesis and embryogenesis from immature cotyledons of pea (Pisum sativum L. were developed. The first system was direct multiple shoot regeneration from the proximal to the embryo axis, injured part of cotyledon. The ability of six Polish cultivars to shoot formation was very high. The percent of regenerating cotyledons was from 73 to 86 and mean number of shoots from 3.5 to 9.9 after seven weeks of culture. This multiplification could be prolonged for next several months. The second system was somatic embryogenesis, initiating from the same part of cotyledon simultaneously with slowly proliferating callus. Only three out of six cultivars formed embryoids. The differences of ability to embryo formation ranged between 43% of responding explants for Heiga cultivar to only 6% for Cud Ameryki. The mean number of embryoids was from 4.2 to 2.3.

  5. [Analysis of tobacco regeneration plants from the protoplasts produced by electrofusion [corrected] in space].

    Science.gov (United States)

    Li, Xiu-Gen; Chen, Ai-Di; Wang, Liu-Fa; Zheng, Hui-Qiong

    2007-10-01

    Vacuolated mesophyll protoplasts of Nicotiana rustica L. were electrically fused with evacuolated protoplasts of the same genus (N. tabacum cv. 'Gexin No.1') during a 7-day space flight in the Chinese spacecraft "SZ-4". The initial cell division leading to micro-callus formation took place after landing (Fig.1). Higher plating efficiencies were observed in the flight samples than the control culture, but the frequency of plantlets regeneration reduced by about 20% of the control (Table 1). The hybrid characters were tested by chromosome counting, isozyme analysis and comparison of morphological characteristics (Figs.2-4). About 32% of the regenerates showed hybrid character. Leaf morphological modifications were found in 3 hybrids, i.e., H23, H25 and H27. After backcrossing with N. rustica, alterations in flower color and leaf shape occurred in the somatic hybrid H23 (Fig.5). These results demonstrate that the hybrids formed under microgravity condition could regenerate fertile plants.

  6. Tissue culture and regeneration of an antimalarial plant, Artemisia sieberi Besser

    Directory of Open Access Journals (Sweden)

    A. Sharafi

    2014-10-01

    Full Text Available WHO recommends artemisinin-based combination therapies (ACTs as the most effective choice to treat malaria. For developing transgenic plants with high accumulation of artemisinin (by introducing genes encoding enzymes which regulate the biosynthetic pathway of artemisinin, an efficient protocol for tissue culture and plant regeneration is necessary. In the present study, leaf explants of Artemisia sieberi were cultivated in Murashige & Skoog based medium supplemented by combination of different plant growth regulators including 6-benzyl-aminopurine (BA, α-naphthalene-acetic acid (NAA, indole-3-acetic acid (IAA, picloram (Pic and 2,4-dichlorophenoxyacetic acid (2,4-D. The highest frequency of shoot induction was obtained on MS medium supplemented with 2 mg/L BA plus 0.05 mg/L NAA (95% regeneration and MS medium supplemented with 2 mg/L BA plus 0.5 mg/L IAA (85% regeneration. Rooting was obtained on MS medium supplemented with 0.05 mg/L NAA. The present study has revealed a simple, reliable, rapid and high efficient regeneration system for A. sieberi Besser as a source of artemisinin in short period via adventitious shoot induction procedure.

  7. Slicing across kingdoms: regeneration in plants and animals.

    Science.gov (United States)

    Birnbaum, Kenneth D; Sánchez Alvarado, Alejandro

    2008-02-22

    Multicellular organisms possessing relatively long life spans are subjected to diverse, constant, and often intense intrinsic and extrinsic challenges to their survival. Animal and plant tissues wear out as part of normal physiological functions and can be lost to predators, disease, and injury. Both kingdoms survive this wide variety of insults by strategies that include the maintenance of adult stem cells or the induction of stem cell potential in differentiated cells. Repatterning mechanisms often deploy embryonic genes, but the question remains in both plants and animals whether regeneration invokes embryogenesis, generic patterning mechanisms, or unique circuitry comprised of well-established patterning genes.

  8. High-frequency in vitro plantlet regeneration from apical bud as a novel explant of Carum copticum L.

    Institute of Scientific and Technical Information of China (English)

    Mansoureh Salehi; Bahman Hosseini; Zohreh Jabbarzadeh

    2014-01-01

    Objective: To develop an in vitro regeneration system to increase the recovery of Carum copticum L. plantlets as a part of developing a metabolic engineering program.Methods:3-acetic acid and indole butyric acid on direct shoot regeneration and rooting of ajowan from apical bud explants were assessed. All explants were cultured on Murashige and Skoog (MS) medium supplemented with different combinations of 6-benzyl amino purine (BAP) (0, 2.2, 4.4, 8.8µ The efficacy of different concentrations and combinations of 6-benzyladenine, indole-Results: The maximum shoot regeneration frequency (97.5%) and the highest number of shoots produced from apical buds (34 shoots per explant) were obtained on MS medium fortified with BAP (4.4 µmol/L) and IAA (0.5 µmol/L). Low shoot regeneration frequency was observed in BAP free treatments. The effects of different strengths of MS medium and various concentrations of IAA and indole-3- butyric acid on rooting rate, length and average number of roots were also investigated. Application of indole-3- butyric acid (6 µmol/L) in full-strength MS medium, was more effective than IAA and resulted in highest shoot regeneration frequency with the rooting rate of 100% and highest mean number of roots per shoot (41.8). The rooted plantlets were acclimatized successfully in greenhouse conditions with a survival rate of 90%. mol/L) and indole-3-acetic acid (IAA) (0, 0.5, 1.1, 2.2 µmol/L). Conclusion: In this study, a simple and reliable regeneration and acclimatization protocol for Carum copticum has been presented. This protocol can be found very advantageous for a variety of purposes, including mass multiplication of Carum species, medicinal plant breeding studies and transgenic plant production.

  9. Effects of inter-culture, arabinogalactan proteins, and hydrogen peroxide on the plant regeneration of wheat immature embryos

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; WANG Xin-min; FAN Rong; YIN Gui-xiang; WANG Ke; DU Li-pu; XIAO Le-le; YE Xing-guo

    2015-01-01

    The regeneration rate of wheat immature embryo varies among genotypes, howbeit many elite agriculture wheat varieties have low regeneration rates. Optimization of tissue culture conditions and attempts of adding signal molecules are effective ways to increase plant regeneration rate. Inter-culture is one of ways that have not been investigated in plant tissue culture. Moreover, the use of arabinogalactan proteins (AGPs) and hydrogen peroxide (H2O2) have been reported to increase regeneration rate in a few plant species other than wheat. The current research pioneeringly uses inter-culture of immature embryos of different wheat genotypes, and also investigates impacts of AGP and H2O2 on the induction of embryogenic cali and plant regeneration. As a result, high-frequency regeneration wheat cultivars Kenong 199 (KN199) and Xinchun 9 (XC9), together with low-frequency regeneration wheat line Chinese Spring (CS), presented striking increase in the induction of embryogenic cali and plant regeneration rate of CS through inter-culture strategy, up to 52.19 and 67.98%, respectively. Adding 50 to 200 mg L–1 AGP or 0.005 to 0.01 ‰ H2O2 to the calus induction medium, enhanced growth of embryogenic cali and plant regeneration rate in quite a few wheat genotypes. At 50 mg L–1 AGP application level in calus induction medium plant regeneration rates of 8.49, 409.06 and 283.16% were achieved for Jimai 22 (JM22), Jingdong 18 (JD18) and Yangmai 18 (YM18), respectively; whereas at 100 mg L–1 AGP level, CS (105.44%), Chuannong 16 (CN16) (80.60%) and Ningchun 4 (NC4) (62.87%) acted the best. Moreover CS (79.05%), JM22 (7.55%), CN16 (101.87%), YM18 (365.56%), Yangmai 20 (YM20) (10.48%), and CB301 (187.40%) were more responsive to 0.005 ‰ of H2O2,and NC4 (35.37%) obtained the highest shoot regeneration rates at 0.01 ‰ of H2O2. Overal, these two methods, inter-culture and AGP (or H2O2) application, can be further applied to wheat transgenic research.

  10. Plants for water recycling, oxygen regeneration and food production

    Science.gov (United States)

    Bubenheim, D. L.

    1991-01-01

    During long-duration space missions that require recycling and regeneration of life support materials the major human wastes to be converted to usable forms are CO2, hygiene water, urine and feces. A Controlled Ecological Life Support System (CELSS) relies on the air revitalization, water purification and food production capabilities of higher plants to rejuvenate human wastes and replenish the life support materials. The key processes in such a system are photosynthesis, whereby green plants utilize light energy to produce food and oxygen while removing CO2 from the atmosphere, and transpiration, the evaporation of water from the plant. CELSS research has emphasized the food production capacity and efforts to minimize the area/volume of higher plants required to satisfy all human life support needs. Plants are a dynamic system capable of being manipulated to favour the supply of individual products as desired. The size and energy required for a CELSS that provides virtually all human needs are determined by the food production capacity. Growing conditions maximizing food production do not maximize transpiration of water; conditions favoring transpiration and scaling to recycle only water significantly reduces the area, volume, and energy inputs per person. Likewise, system size can be adjusted to satisfy the air regeneration needs. Requirements of a waste management system supplying inputs to maintain maximum plant productivity are clear. The ability of plants to play an active role in waste processing and the consequence in terms of degraded plant performance are not well characterized. Plant-based life support systems represent the only potential for self sufficiency and food production in an extra-terrestrial habitat.

  11. Plants for water recycling, oxygen regeneration and food production

    Science.gov (United States)

    Bubenheim, D. L.

    1991-01-01

    During long-duration space missions that require recycling and regeneration of life support materials the major human wastes to be converted to usable forms are CO2, hygiene water, urine and feces. A Controlled Ecological Life Support System (CELSS) relies on the air revitalization, water purification and food production capabilities of higher plants to rejuvenate human wastes and replenish the life support materials. The key processes in such a system are photosynthesis, whereby green plants utilize light energy to produce food and oxygen while removing CO2 from the atmosphere, and transpiration, the evaporation of water from the plant. CELSS research has emphasized the food production capacity and efforts to minimize the area/volume of higher plants required to satisfy all human life support needs. Plants are a dynamic system capable of being manipulated to favour the supply of individual products as desired. The size and energy required for a CELSS that provides virtually all human needs are determined by the food production capacity. Growing conditions maximizing food production do not maximize transpiration of water; conditions favoring transpiration and scaling to recycle only water significantly reduces the area, volume, and energy inputs per person. Likewise, system size can be adjusted to satisfy the air regeneration needs. Requirements of a waste management system supplying inputs to maintain maximum plant productivity are clear. The ability of plants to play an active role in waste processing and the consequence in terms of degraded plant performance are not well characterized. Plant-based life support systems represent the only potential for self sufficiency and food production in an extra-terrestrial habitat.

  12. Isolation, culture, and plant regeneration from leaf protoplasts of Passiflora.

    Science.gov (United States)

    Davey, Michael R; Anthony, Paul; Power, J Brian; Lowe, Kenneth C

    2006-01-01

    The family Passifloraceae contains many species exploited in the food, pharmaceutical, and ornamental plant industries. The routine culture of isolated protoplasts (naked cells) followed by reproducible plant regeneration, is crucial to the genetic improvement of Passiflora spp. by somatic cell technologies. Such procedures include somatic hybridization by protoplast fusion to generate novel hybrid plants, and gene introduction by transformation. Seedling leaves are a convenient source of totipotent protoplasts. The protoplast-to-plant system developed for Passiflora edulis fv. flavicarpa is summarized in this chapter. The procedure involves enzymatic degradation of leaf tissue using commercially-available Macerozyme R10, Cellulase R10, and Driselase. Isolated protoplasts are cultured in Kao and Michayluk medium, semi-solidified with agarose. The medium containing the suspended protoplasts is dispensed as droplets or thin layers and bathed in liquid medium of the same composition. Shoot regeneration involves transfer of protoplast-derived tissues to Murashige and Skoog-based medium. The protocols developed for P. edulis are applicable to other Passiflora spp. and will underpin the future biotechnological exploitation of a range of species in this important plant family.

  13. In vitro Plant Regeneration from the Mature Tissue of Navel Orange (Citrus sinensis L. Osbeck) by Direct Organogenesis

    Institute of Scientific and Technical Information of China (English)

    HUANG Jia-quan; YIN Li-yan; YANG Xiao-hong; SUN Zhong-hai

    2005-01-01

    An efficient in vitro regeneration system by direct organogenesis from mature nodal and internodal stem segments of Newhall navel orange (Citrus sinensis L. Osbeck) was developed. Illuminating conditions together with plant growth regulators affected the adventitious bud regeneration frequency and efficiency. The initial 15 d darkness inoculation is beneficial for the adventitious bud regeneration. The highest regeneration frequency (85.2%) and bud formation efficiency (3.7 per responsive internodal stem segment) were obtained in the media supplemented with 1.0 mg L-1 BAP and 0.5 mg L-1 NAA. ABA at 0.2 mg L-1 positively affected the bud formation efficiency, which amounted to 8.5 buds per internodal segment in the presence of BAP at 1.0 mg L-1. The adventitious shoots successfully rooted and were transferred to the soil.

  14. Advanced Regenerator for High Frequency Low Temperature Operation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key element in producing an efficient low temperture cryocooler is the performance of the regenerator. It must have good heat transfer characteristics while...

  15. Numerical Simulation of Flow and Heat Transfer Characteristic of 4k Regenerators at High Frequency

    Science.gov (United States)

    Li, Zhuopei; Jiang, Yanlong; Gan, Zhihua; Qiu, Limin

    Regenerator is a key component for all regenerative cryocoolers. 4K regenerative cryocoolers can be applied to provide cooling for low temperature superconductors, space and military infrared detectors, and medical examination etc. Stirling type pulse tube cryocoolers (SPTC), one type of regenerative cryocoolers, operate at high frequencies. As a result, SPTCs have the advantage of compact structure and low weight compared with G-M type pulse tube cryocoolers operating at low frequencies. However, as the frequency increase the thermal penetration depth of helium gas in the regenerator is greatly reduced which makes the heat transfer between the gas and the regenerator worse. In order to improve the heat transfer efficiency, regenerator materials with smaller hydraulic diameters are used. Therefore the flow resistance between the gas and the regenerator material will increase leading to larger pressure drop from the hot end to the cold end of the regenerator. The cooling performance is deteriorated due to the decreased pressure ratio (maximum pressure divided by minimum pressure) at the cold end. Also, behavior of helium at 4K deviates remarkably from that of ideal gas which has a significant influence both the flow and heat transfer characteristic within a regenerator. In this paper numerical simulation on the behavior of a 4K regenerator at high frequency is carried out to provide guidance for the optimization of the flow and heat transfer performance within a regenerator. Thermodynamic analysis of effect of the non-ideal gas behavior of helium at 4K on 4K regenerator at high frequency is investigated.

  16. Plant Regeneration from Immature Inflorescence Culture and Genetic Transformation of Wheatgrass (Agropyron cristatum × A. Desertorum cv. Hycrest-Mengnong)

    Institute of Scientific and Technical Information of China (English)

    HUO Xiu-wen; WEI Jian-hua; XU Chun-bo; MI Fu-gui; YUN Jin-feng

    2006-01-01

    The plants of hybrid wheatgrass (A. Cristatum ×A. Desertorum cv. Hycrest-Mengnong) were directly induced from embryogenic callus regenerated from immature inflorescence. Immature inflorescence was cultured on improved MS medium containing 2.0-3.0 mg L-1 2,4-D to regenerate callus. The calli were then transferred to hormone-free MS medium for differentiation and 1/2 MS medium for rooting. Results showed that callus initiation frequency was 83.4% and plant regeneration frequency was 59.6%. Phosphinothricin acetyltransferase (bar) gene was transformed into the hybrid wheatgrass by particle bombardment. Resistant callus was obtained using selecting agent, herbicide glufosinate of 0.5 mg L-1, and some transgenic plants were recovered in vitro. The transgenic plants were identified by PCR and Southern blot analysis and these plants developed normally in the glufosinate medium, whereas the nontransgenic plants did not. The results demonstrated that bar cDNA integrated into the genomic DNA of the transgenic plants. The transgenic frequencies of bar gene were 1.1%.

  17. Plant regeneration from protoplast of Brazilian citrus cultivars

    Directory of Open Access Journals (Sweden)

    GLORIA FERNANDA JANUZZI MENDES DA

    2000-01-01

    Full Text Available A procedure is described to regenerate plants from protoplasts of Brazilian citrus cultivars, after isolation, fusion and culture. Protoplasts were isolated from embryogenic cell suspension cultures and from leaf mesophyll of seedlings germinated in vitro. The enzyme solution for protoplast isolation was composed of mannitol (0.7 M, CaCl2 (24.5 mM, NaH2PO4 (0.92 mM, MES (6.15 mM, cellulase (Onozuka RS - Yakult, 1%, macerase (Onozuka R10 - Yakult, 1% and pectolyase Y-23 (Seishin, 0.2%. Protoplast culture in liquid medium after chemical fusion lead to the formation of callus colonies further adapted to solid medium. Somatic embryo formation occurred spontaneously after two subcultures, on modified MT medium supplemented with 500 mg/L of malt extract. Well defined embryos were germinated in modified MT medium with addition of GA3 (2.0 muM and malt extract (500 mg/L. Plant regeneration was also achieved by adventitious shoots obtained through direct organogenesis of not well defined embryos in modified MT medium with addition of malt extract (500 mg/L, BAP (1.32 muM, NAA (1.07 muM and coconut water (10 mL/L. Plantlets were transferred to root medium. Rooted plants were transferred to a greenhouse for further adaptation and development.

  18. Plant regeneration and genetic transformation in switchgrass-A review

    Institute of Scientific and Technical Information of China (English)

    Paul Merrick; Shuizhang Fei

    2015-01-01

    Switchgrass is native to the tal grass prairie of North America. It is self-incompatible and has varied ploidy levels from diploid (2x) to dodecaploid (12x) with tetraploid and octoploid being the most common. The high yielding potential and the ability to grow wel in marginal lands make switchgrass an ideal species as a dedicated biomass producer for lignocel ulosic ethanol production. Genetic transformation is an important tool for studying gene function and for germplasm improvement in switchgrass, the genome of which has been sequenced recently. This paper intends to provide a comprehensive review on plant regeneration and genetic transformation in switchgrass. We ifrst reviewed the effect of explants, basal medium and plant growth regulators on plant regeneration in switchgrass, which is a prerequisite for genetic transformation. We then reviewed the progresses on genetic transformation with either the biolistic or Agrobacterium-mediated method in switchgrass, and discussed various techniques employed to improve the transformation efifciency. Final y we reviewed the recent progresses on the use of genetic transformation in improving biomass quality such as the reduction of lignin, and in increasing biomass yield in switchgrass. We also provided a future perspective on the use of new genome editing technologies in switchgrass and its potential impact on regulatory processes.

  19. Effects of gaps on regeneration of woody plants:a meta-analysis

    Institute of Scientific and Technical Information of China (English)

    Jiaojun Zhu; Deliang Lu; Weidong Zhang

    2014-01-01

    Forest gaps, openings in the canopy caused by death of one or more trees, have a profound effect on forest regeneration and drive the forest growth cycle. It is therefore necessary to understand the effects of forest gaps on regeneration for modern forest management. In order to provide a quantitative assessment of the effects of forest gaps on regen-eration of woody plants, we conducted this review of gap effects on woody plant regeneration on the basis of 527 observations from 42 indi-vidual papers, and reported the results of these data in a meta-analysis. Overall, densities of regenerated woody plants were significantly greater (359%) in forest gaps than on the closed-canopy forest floor. The regen-eration density in gaps of plantation forests was significantly greater (P<0.05) than that of natural forest because the regeneration in gaps of plan-tation forests was improved by both gap effects and experimental meas-ures. Similarly, in comparison to natural gaps, regeneration was better enhanced in artificial gaps. Regeneration density exhibited a significantly positive correlation with gap size, but a negative correlation with gap age because the gap size decreased with increasing gap age. Shade tolerance of woody plants affected regeneration density in gaps and understory. Average regeneration density of shade-tolerant species exhibited a sig-nificantly positive response to gaps but densities remained lower in total than those of intermediate and shade-intolerant species. Gap effects on regeneration decreased in response to increasing temperature and pre-cipitation because of the limiting effects of lower temperature and moisture on woody plant regeneration. In summary, forest gaps enhance woody plant regeneration, and the effects of gaps varied by forest type, gap characteristics, environmental factors and plant traits. The results of this meta-analysis are useful for better understanding the effects and roles of gaps on forest regeneration and forest

  20. Thidiazuron: A potent cytokinin for efficient plant regeneration in Himalayan poplar (Populus ciliata Wall. using leaf explants

    Directory of Open Access Journals (Sweden)

    Gaurav Aggarwal

    2012-11-01

    Full Text Available Populus species are important resource for certain branches of industry and have special roles for scientific study on biological and agricultural systems. The present investigation was undertaken with an objective of enhancing the frequency of plant regeneration in Himalayan poplar (Populus ciliata Wall.. The effect of Thiadizuron (TDZ alone and in combination with adenine and α-Naphthalene acetic acid (NAA were studied on the regeneration potential of leaf explants. A high efficiency of shoot regeneration was observed in leaf (80.00% explants on MS basal medium supplemented with 0.024 mg/l TDZ and 79.7 mg/l adenine. Elongation and multiplication of shoots were obtained on Murashige and Skoog (MS basal medium, containing 0.5 mg/l 6. Benzyl aminopurine (BAP + 0.2mg/l Indole 3-acetic acid (IAA + 0.3 mg/l Gibberellic acid (GA3. High frequency root regeneration from in vitro developed shoots was observed on MS basal medium supplemented with 0.10 mg/l Indole 3-butyric acid(IBA. Maximum of the in vitro rooted plantlets were well accomplished to the mixture of sand: soil (1:1 and exhibited similar morphology with the field plants. A high efficiency plant regeneration protocol has been developedfrom leaf explants in Himalayan poplar (Populus ciliata Wall..

  1. Protoplast-to-plant regeneration of American elm (Ulmus americana).

    Science.gov (United States)

    Jones, A M P; Shukla, M R; Biswas, G C G; Saxena, P K

    2015-05-01

    This study describes a protocol for regeneration of plants from cell suspension-derived protoplasts of American elm (Ulmus americana). Efficient protoplast isolation was achieved from a two-phase culture system through the incorporation of 100 μM 2-aminoindan-2-phosphonic acid, with a yield of approximately 2 × 10(6) protoplasts/ml packed cell volume. Isolated protoplasts failed to survive in liquid or alginate bead culture systems but initiated and continued to divide when embedded in low melting point agarose beads. Protoplast-derived callus proliferated and differentiated into shoot buds in response to 10 or 20 μM thidiazuron. Differentiated buds elongated and continued to proliferate on elm shoot medium supplemented with 3.0 μM GA3. The protoplast-derived shoots rooted and acclimatized to greenhouse conditions and continued to grow. This system provides the first protoplast-to-plant regeneration system for American elm and provides a framework for the development of protoplast fusion or genome editing technologies.

  2. Shoot multiplication and plant regeneration in Caragana fruticosa (Pall.) Besser

    Institute of Scientific and Technical Information of China (English)

    ZHAI Xiao-jie; YANG Ling; SHEN Hai-long

    2011-01-01

    Different nutrient media can affectin vitro culturing protocols,and experimentation under varied growth conditions is valuable in plants where in vitro methods are in preliminary stages.We carried out the first in vitro propagation studies for the endangered species Caragana fruticosa (Fabaceae).We evaluated various nutrient media for their inpact on shoot elongation and axillary bud proliferation using different concentrations of 6-benzylaminopurine (BA) and α-naphthaleneacetic acid (NAA).Shoot elongation was evaluated based on adventitious shoot primary culture and subculture regeneration from Caragana seedlings.Our goal was to improve both micropropagation and regeneration in C.fruticosa.MS nutrient media was superior to 1/2MS macronutrients,DKW,QL,and WPM for shoot elongation and axillary shoot proliferation.Shoots grown on 1/2MS and WPM exhibited some chlorosis,and shoots on QL produced larger leavers than plants growing on normal medium.The shoot proliferation coefficient on MS media supplemented with 2.22 μM BA and 0.44 μM BA + 2.69 μM NAA was significantly higher than that with other treatments in the primary culture.Shoots on 2.22 μM BA showed a higher proliferation coefficient (3.17) than others in the subculture.Shoots were rooted on 1/2MS medium with the addition of different concentrations of NAA.The optimal concentration for rooting was 0.27 μM NAA (74%).Roots exhibited many stout and long root hairs.Survivl of established plantlets was 82% at 30 days after transfer to soil.Plants established in the green house showed normal growth and displayed no apparent morphological differences compared to stock plants.

  3. Positive interactions between herbivores and plant diversity shape forest regeneration.

    Science.gov (United States)

    Cook-Patton, Susan C; LaForgia, Marina; Parker, John D

    2014-05-22

    The effects of herbivores and diversity on plant communities have been studied separately but rarely in combination. We conducted two concurrent experiments over 3 years to examine how tree seedling diversity, density and herbivory affected forest regeneration. One experiment factorially manipulated plant diversity (one versus 15 species) and the presence/absence of deer (Odocoileus virginianus). We found that mixtures outperformed monocultures only in the presence of deer. Selective browsing on competitive dominants and associational protection from less palatable species appear responsible for this herbivore-driven diversity effect. The other experiment manipulated monospecific plant density and found little evidence for negative density dependence. Combined, these experiments suggest that the higher performance in mixture was owing to the acquisition of positive interspecific interactions rather than the loss of negative intraspecific interactions. Overall, we emphasize that realistic predictions about the consequences of changing biodiversity will require a deeper understanding of the interaction between plant diversity and higher trophic levels. If we had manipulated only plant diversity, we would have missed an important positive interaction across trophic levels: diverse seedling communities better resist herbivores, and herbivores help to maintain seedling diversity.

  4. [Two interspecific somatic hybrid plants regenerated via protoplast electro-fusion].

    Science.gov (United States)

    Guo, W W; Deng, X X

    2000-03-01

    Protoplasts isolated from cell suspension cultures of 'Bonnaza' navel orange (Citrus sinensis L. Osbeck) were electrically fused with mesophyll protoplasts of rough lemon (Citrus jambhiri Lush) and Goutou orange (Citrus aurantium L.) respectively. Plants regenerated from both fusion combinations. Chromosome counting of randomly selected fifty two globular embryoids as well as all the regenerated seventy four plants from Bonnaza navel + rough lemon revealed that twenty six embryoids were tetraploids, and the rest were diploids while 100% regenerated plants were tetraploids. The results inferred that somatic hybrids were more competitive than parental genotypes in the process of plant regeneration. All the regenerated 14 plants from Bonnaza navel + Goutou orange were tetraploids as revealed by chromosome counting. POX isozyme and RAPD analysis verified that the plants from Bonnaza navel + rough lemon were hybrids, and RAPD analysis confirmed the hybridity of those from Bonnaza navel + Goutou orange.

  5. Regeneration of haploid plants from isolated microspores of asparagus (Asparagus officinalis L.).

    Science.gov (United States)

    Zhang, C J; Wang, H L; Ma, Y; Kang, Y Q

    1994-08-01

    High percentages of micro-calli and micro-derived embryos were produced from isolated asparagus microspores at late uninucleate stage on MS liquid medium supplemented with 1.0 mg l(-1) 2,4-D and 0.5 mg l(-1) BA. Two types of calli, namely compact callus (CC) and loose callus (LC), were found. Plantlets were regenerated via organogenesis, when these calli were transferred onto MS solid medium supplemented with 1.0 mg l(-1) BA and 0.2 mg l(-1) IBA 6 weeks. Embryos were produced from liquid cultured microspores, or from solid cultured micro-calli. The frequencies of haploid plant production from organogenesis and embryogenesis were compared. Effects of plant growth regulators on callus production, plantlet regeneration, and haploid plant production were tested. The combination of BA 1.0 mg l(-1) and IBA 0.2 mg l(-1) resulted the highest precentage of haploid plant production (7.7% from CC, 4.3% from LC).

  6. Protoplast culture and plant regeneration of several species in the genus Dianthus.

    Science.gov (United States)

    Nakano, M; Mii, M

    1992-06-01

    Seventeen cultivars belonging to the genus Dianthus were examined for protoplast isolation, culture and shoot regeneration under the same conditions. These included D. caryophyllus, D. chinensis, D. barbatus, D. plumarius, D. superbus and D. japonicus as well as interspecific hybrid cultivars (D. caryophyllus x D. chinensis and D. chinensis x D. barbatus). In all cultivars, viable protoplasts were isolated at high yields from leaves of axenic shoot cultures and some of these protoplasts divided and formed colonies. However, shoot regeneration frequencies were markedly different among the species. High frequency shoot regeneration was obtained from D. chinensis and interspecific hybrid cultivars, while only low frequency or no shoot regeneration was obtained from other species.

  7. Evaluation of haemoglobin (erythrogen): for improved somatic embryogenesis and plant regeneration in cotton (Gossypium hirsutum L. cv. SVPR 2).

    Science.gov (United States)

    Ganesan, M; Jayabalan, N

    2004-10-01

    Somatic embryogenesis in cotton (Gossypium hirsutum L.) is accelerated when the plant regeneration medium is supplemented with haemoglobin (erythrogen). In cotton SVPR 2 lines, a higher frequency of embryoid formation was observed when the medium contained 400 mg/l haemoglobin. Fresh weight of the callus, rate of embryoid induction, number of embryoids formed and the percentage of plant regeneration from somatic embryos were increased. Among the two different cultivars tested, MCU 11 showed no response to the presence of haemoglobin when compared to SVPR 2, and embryogenic callus formation was completely absent in the former. Medium containing MS salts, 100 mg/l myo-inositol , 0.3 mg/l thiamine-HCL, 0.3 mg/l Picloram (PIC), 0.1 mg/l kinetin and 400 mg/l haemoglobin effected a better response with respect to embryogenic callus induction. After 8 weeks of culture, a high frequency of embryoid induction was observed on medium containing MS basal salts, 100 mg/l myo-inositol, 0.3 mg/l PIC , 0.1 mg/l isopentenyl adenine, 1.0 g/l NH4NO3 and 400 mg/l haemoglobin. Plant regeneration was observed in 75.8% of the mature somatic embryos, and whole plant regeneration was achieved within 6-7 months of culture. The regenerated plantlets were fertile and similar to in vivo-grown, seed-derived plants except that they were phenotypically smaller. A positive influence of haemoglobin was observed at concentrations up to 400 mg/l at all stages of somatic embryogenesis. The increase in the levels of antioxidant enzyme activities, for example superoxide dismutase and peroxidase, indicated the presence of excess oxygen uptake and the stressed condition of the plant tissues that arose from haemoglobin supplementation. This increased oxygen uptake and haemoglobin-mediated stress appeared to accelerate somatic embryogenesis in cotton.

  8. Plant regeneration through somatic embryogenesis and genome size analysis of Coriandrum sativum L.

    Science.gov (United States)

    Ali, Muzamil; Mujib, A; Tonk, Dipti; Zafar, Nadia

    2017-01-01

    In the present study, an improved plant regeneration protocol via primary and secondary somatic embryogenesis was established in two Co-1 and Rajendra Swathi (RS) varieties of Coriandrum sativum L. Callus was induced from root explants on 2, 4-D (0.5-2.0 mg/l) supplemented MS. The addition of BA (0.2 mg/l) improved callus induction and proliferation response significantly. The maximum callus induction frequency was on 1.0 mg/l 2, 4-D and 0.2 mg/l BA added MS medium (77.5 % in Co-1 and 72.3 % in RS). The callus transformed into embryogenic callus on 2, 4-D added MS with maximum embryogenic frequency was on 1.0 mg/l. The granular embryogenic callus differentiated into globular embryos on induction medium, which later progressed to heart-, torpedo- and cotyledonary embryos on medium amended with 0.5 mg/l NAA and 0.2 mg/l BA. On an average, 2-3 secondary somatic embryos (SEs) were developed on mature primary SEs, which increased the total embryo numbers in culture. Histology and scanning electron microscopy (SEM) studies are presented for the origin, development of primary and secondary embryos in coriander. Later, these induced embryos converted into plantlets on 1.0 mg/l BA and 0.2 mg/l NAA-amended medium. The regenerated plantlets were cultured on 0.5 mg/l IBA added ½ MS for promotion of roots. The well-rooted plantlets were acclimatized and transferred to soil. The genetic stability of embryo-regenerated plant was analyzed by flow cytometry with optimized Pongamia pinnata as standard. The 2C DNA content of RS coriander variety was estimated to 5.1 pg; the primary and secondary somatic embryo-derived plants had 5.26 and 5.44 pg 2C DNA content, respectively. The regenerated plants were genetically stable, genome size similar to seed-germinated coriander plants.

  9. In vitro plant regeneration of Spartina argentinensis Parodi

    Directory of Open Access Journals (Sweden)

    Mirian Susana Bueno

    2012-08-01

    ; in vitro; organogénesis; variación somaclonal. Abstract: Spartina argentinensis Parodi is the dominant species of the temporally-flooded halophyte communities of the Santa Fe Province, Argentina. It occupies around 20,000 km2 and it is mainly used as low-cost impute forage for cattle production. The objective of this work was to develop a simple method for in vitro plant regeneration of S. argentinensis that could be used for fundamental and applied research. Leaf-basal segments from both young and mature plants, roots tips and immature inflorescences were used as explants. Culture media for calli, shoot, and root induction consisted of Murashige & Skoog salts supplemented with different plant growth regulators (2,4-D; BAP or ANA. Most of the explants (with the exception of root tips showed cell proliferation and calli formation after 30 days of culture. However, only immature inflorescences responded to shoot and root induction when calli were incubated on MS salts plus 2,4_D and BAP (0.1 and 0.01 mg.L-1, respectively, transferred to shoot inductionmedia (MS salts plus BAP, 0.5 mg.L-1 and then to root induction media (MS slts plus NAA 0.5 mg.L-1. Regenerated plants were evaluated for morphological abnormalities and lignin content. Historical analysis of regenerating calli showed that shoots and roots originated via organogenesis. A low proportion of regenerated plants resulted with deficiency in chlorophyll (albino plants and other morphological abnormalities. Interestingly, significant variations in the lignin content were detected between regenerated plants. The protocol described in this work could be used ordinarily for S. argentinensis in vitro plant regeneration and selecting somaclonal variants for breeding purposes. Key words: Spartina argentinensis; in vitro; organogenesis; somaclonal variation.

  10. Isolation, culture, and plant regeneration from Echinacea purpurea protoplasts.

    Science.gov (United States)

    Pan, Zeng-guang; Liu, Chun-zhao; Murch, Susan I; Saxena, Praveen K

    2006-01-01

    A plant regeneration system from the isolated protoplasts of Echinacea purpurea L. using an alginate solid/liquid culture is described in the chapter. Viable protoplasts were isolated rom 100 mg of young leaves of 4-wk-old seedlings in an isolation mixture containing 1.0% cellulase Onozuka R-10, 0.5% pectinase, and 0.3 mol/L mannitol. After isolation and purification, the mesophyll protoplasts were embedded into 0.6% Na-alginate at the density 1 x 10(-5) mL and cultured in modified Murashige and Skoog (MS) culture medium supplemented with 0.3 mol/L sucrose, 2.5 micromol/L benzylaminopurine (BA), and 5.0 micromol/L 2,4-dichlorophenoxyacetic acid (2,4-D). The visible colonies were present after 4 wk of culture. The protoplast-derived clones were transferred onto gellan gum-solidified basal medium supplemented with 1.0 micromol/L BA and 2.0 micromol/L indole-3-butyric acid (IBA) and formed compact and green calli. Shoot development was achieved by subculturing the calli onto the same basal medium supplemented with 5.0 micromol/L BA and 2.0 micromol/L IBA. Further subculture onto basal medium resulted in the regeneration of complete plantlets.

  11. Embryogenesis and plant regeneration of Medicago spp. in tissue culture.

    Science.gov (United States)

    Nagarajan, P; McKenzie, J S; Walton, P D

    1986-02-01

    Ten cultivars and breeding lines from two species of alfalfa (Medicago media and M. sativa) were screened for their ability to produce embryos and plantlets from the root and hypocotyl under three different tissue culture protocols. The three protocols differed in basal salt composition, vitamins, hormones and cytokinin additions. That protocol having a high 2-4,D low cytokinin induction step gave the highest percentage of embryogenic calli in some cultivars and lines. M. media cultivars and breeding lines had a high percentage of embryoid formation. M. sativa cultivars gave no embryoid formation. Two M. media breeding lines (Br1 and Le1), which were intermediate in the percentage of embryogenic calli formed from explants, had the highest number of regenerated plants established in soil. The creeping rooted M. media cultivar Heinrichs produced the highest percentage of embryogenic calli from explants but most of these embryoids were abnormal and failed to grow in soil or vermiculite. Accordingly, successful regeneration is directly related to the quality and quantity of the embryoids produced.

  12. Somaclonal variation in Asparagus officinalis plants regenerated by organogenesis from long-term callus cultures

    Directory of Open Access Journals (Sweden)

    Pontaroli Ana Clara

    2005-01-01

    Full Text Available Somaclonal variation in plants regenerated by organogenesis from long-term cultured calluses of two diploid staminate genotypes of Asparagus officinalis cv. Argenteuil was characterized by plant phenotype, ploidy, meiotic behavior, pollen viability, fruit and seed set, and AFLP profiles. Phenotypic deviations from the donors were detected in foliage color, flower size, and cladode and flower morphology. Ploidy changes were observed in 37.8% of the 37 regenerants studied. Meiotic alterations in 12 out of 21 regenerants included laggards, dicentric bridges, micronuclei, restitution nuclei and polyads. Of the 408 AFLP markers screened in 43 regenerants and the donors, 2.94% showed polymorphism. High pollen viability was observed in the 22 regenerants analyzed. All crosses between one pistillate plant and 35 regenerants, as well as the controls, produced fruits and seeds; however, no plump seeds resulted in 35.3% of the crosses with regenerants, and no seeds germinated in 12.5% of those with apparently normal seeds. Fruit and seed set was similar in crosses with diploid regenerants with normal meiosis and the controls but was lower in crosses with diploid and polyploid regenerants with abnormal meiosis. Our results show that the regenerated plants exhibited conspicuous somaclonal variation that could be eventually exploited for in vitro selection systems.

  13. Shoot regeneration from cotyledonary leaf explants of jatropha curcas: A biodiesel plant

    KAUST Repository

    Kumar, Nitish Chandramohana

    2010-03-07

    A simple, high frequency, and reproducible method for plant regeneration through direct organogenesis from cotyledonary leaf explants of Jatropha curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ) or 6-benzyl aminopurine (BAP). Medium containing TDZ has greater influence on regeneration as compared to BAP. The induced shoot buds were transferred to MS medium containing 10 lM kinetin (Kn), 4.5 lM BAP, and 5.5 lM a-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with different concentrations and combinations of BAP, indole-3-acetic acid (IAA), NAA, and indole-3-butyric acid (IBA). MS medium with 2.25 lM BAP and 8.5 lM IAA was found to be the best combination for shoot elongation. However, significant differences in plant regeneration and shoot elongation were observed among the genotypes studied. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing dif- ferent concentrations and combinations of IBA, IAA, and NAA for 4 days, followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg l-1 activated charcoal. Elongated shoot treated with 15 lM IBA, 5.7 lM IAA, and 11 lM NAA resulted in highest percent rooting. The rooted plants could be established in soil with more than 90% survival rate. The method developed may be useful in improvement of J. curcas through genetic modification. © Franciszek Górski Institute of Plant Physiology, Polish Academy of Sciences, Kraków 2010.

  14. New Development of Acid Regeneration in Steel Pickling Plants

    Institute of Scientific and Technical Information of China (English)

    W F Kladnig

    2008-01-01

    For acid pickling heat treated mild steel and steel products,up to the middle of the last century,sulfuric acid was primarily in use,which has been replaced stepwise by hydrochloric acid since the sixties.During this time,the pickling of high alloyed steel with hydrofluoric acid or mixtures for hydrofluoric acid together with nitric acid has also been applied on industrial scale.The technologies used by several plant contractors hereby show considerable differences in their engineering.The study provides a survey of the progress in the state of art of regeneration technology as well as the use of different pickling media in the form of a review on existing technologies as well as improvements done within the recent years in the area.

  15. Plant regeneration from cultured protoplasts of a glutinous rics

    Institute of Scientific and Technical Information of China (English)

    WangGuangyuan; HsiaChenau; 等

    1990-01-01

    Young embryos of ricy (Oryza sativa L.subsp.japonica var.Guo-xiang No.1) were cultured on MS agar medium(2,4-D 2 mg/l).Calli were formed and subcultured on N6 agar medium (2,4-D 2 mg/l).After selection,the small,grainy and pale yellowish cell clusters with dense cytoplasm were used in protoplast preparation. Isolated protoplasts were cultured in N6 medium (2,4-D 1 mg/l,6-BA 0.2 mg/l)1* with agarose block culture method.The protoplasts grew,divided and formed calli.After inducing differentiation,the regenerated mature plants were obtained.

  16. TDZ-induced plant regeneration in Astragalus cicer L.

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... rangeland and in establishment of artificial meadows. It is adaptable to ... water and were cultured at 24±2°C under fluorescent light (35 µmol m-2 s-1) in a ... type and plant growth regulator concentrations on the frequen-cy of ...

  17. Studies on Callus Induction and Regeneration of Medicinal Plant Chicory (Cichorium intybus L. from Leaf and Petiole Explants

    Directory of Open Access Journals (Sweden)

    H. Hadizadeh

    2016-07-01

    C ± 2 with a 16/8 hour (day/night photoperiod and an irradiance of 1500 LUX using Sylvania cool white fluorescent tubes. The percentage of callus induction, shoot regeneration and the number of regenerated shoots were calculated for the leaf and petiole explants. Data was subjected for analysis of variance and means were compared in 5% level with Duncan’s multiple range tests. Results and Discussion: Explants cultured on medium containing either no plant growth regulators (control or cytokines alone produced no callus. However, after 2 weeks, other concentrations of NAA and BA indicated callus formation from leaf and petiole explants in all hormone combinations. In leaf explants, the highest callus induction were obtained in the medium containing 0.3 mg l-1 NAA with 1 mg l-1 KIN and 0.3 mg l-1 NAA with 1.5 mg l-1 KIN (81.25%. Leaf and petiole explants cultured on medium containing no plant growth regulators (control treatment and medium containing NAA produced no shoots. The combination of 0.3 mg l-1 NAA and 0.1 mg l-1 BA was the best treatment tested. This treatment produced 2.7 shoots per explant at 71% shoot regeneration frequency in leaf explant and 2.73 shoots per explant at 73% shoot regeneration frequency in petiole explants. The results also showed that the highest percentage of regeneration and the highest number of regenerated shoots were obtained in the medium containing 0.1 mg l-1 NAA and 1 mg l-1 KIN in leaf explants (65.6% regeneration and 1.37 shoots per explant, respectively. The highest number of regenerated shoots was obtained in the medium containing 0.3 mg l-1 NAA and 0.5 mg l-1 KIN in petiole explants (40.6% regeneration and 0.5 shoot per explants, respectively. Shoot regeneration requires plant cells to undergo dedifferentiation which is known to be affected by not only exogenous plant growth regulators but also endogenous content of the hormones. Different tissues may have different levels of endogenous hormones and, therefore, the type of

  18. Rapid plant regeneration and analysis of genetic fidelity of in vitro derived plants of Chlorophytum arundinaceum Baker--an endangered medicinal herb.

    Science.gov (United States)

    Lattoo, S K; Bamotra, S; Sapru Dhar, R; Khan, S; Dhar, A K

    2006-06-01

    An efficient in vitro multiplication system via multiple shoot bud induction and regeneration has been developed in Chlorophytum arundinaceum using shoot crown explants. Optimum regeneration frequency (87%) and desirable organogenetic response in the form of de novo organized multiple shoot buds without an intervening callus phase was obtained on Murashige and Skoog's (MS) minimal organics medium containing 3% sucrose (w/v) supplemented with 4 x 10(-6) M Kn and 2 x 10(-6) MIBA. Axenic secondary explants with multiple shoot buds on subculturing elicited best response with 1 x 10(-5) M Kinetin (Kn) and 5 x 10(-6) M indole-3-butyric acid (IBA) giving rise to an average of 18.74 shoots per culture with mean shoot length of 7.6 cm +/- 1.73. Varying molar ratios of either Kn/IBA or Kn/NAA revealed statistically significant differences in the regeneration frequencies among the phytohormone treatments. It was observed that the shoot bud differentiation and regeneration was influenced by the molar ratios of cytokinins/auxin rather than their relative concentrations. Healthy regenerated shoots were rooted in half strength MS basal medium containing 3% sucrose (w/v) supplemented with 5 x 10(-6) M IBA. Following simple hardening procedures, rooted plantlets, were transferred to soil-sand (1:1; v/v) with more than 90% success. Genetic fidelity was assessed using random amplified polymorphic DNA (RAPD), karyotype analysis and meiotic behaviour of in vitro and in vivo plants. Five arbitrary decamers displayed same banding profile within all the micropropagated plants and in vivo explant donor. The cytological and molecular analysis complemented and compared well and showed no genomic alterations in the plants regenerated through shoot bud differentiation. High multiplication frequency, molecular, cytological and phenotypic stability ensures the efficacy of the protocol developed for the production and conservation of this important endangered medicinal herb.

  19. Enhancing plant regeneration in tissue culture: a molecular approach through manipulation of cytokinin sensitivity.

    Science.gov (United States)

    Hill, Kristine; Schaller, G Eric

    2013-10-01

    Micropropagation is used for commercial purposes worldwide, but the capacity to undergo somatic organogenesis and plant regeneration varies greatly among species. The plant hormones auxin and cytokinin are critical for plant regeneration in tissue culture, with cytokinin playing an instrumental role in shoot organogenesis. Type-B response regulators govern the transcriptional output in response to cytokinin and are required for plant regeneration. In our paper published in Plant Physiology, we explored the functional redundancy among the 11 type-B Arabidopsis response regulators (ARRs). Interestingly, we discovered that the enhanced expression of one family member, ARR10, induced hypersensitivity to cytokinin in multiple assays, including callus greening and shoot induction of explants. Here we 1) discuss the hormone dependence for in vitro plant regeneration, 2) how manipulation of the cytokinin response has been used to enhance plant regeneration, and 3) the potential of the ARR10 transgene as a tool to increase the regeneration capacity of agriculturally important crop plants. The efficacy of ARR10 for enhancing plant regeneration likely arises from its ability to transcriptionally regulate key cytokinin responsive genes combined with an enhanced protein stability of ARR10 compared with other type-B ARRs. By increasing the capacity of key tissues and cell types to respond to cytokinin, ARR10, or other type-B response regulators with similar properties, could be used as a tool to combat the recalcitrance of some crop species to tissue culture techniques.

  20. In vitro plant regeneration system for tropical butternut squash genotypes (Cucurbita moschata

    Directory of Open Access Journals (Sweden)

    Marta Valdez-Melara

    2009-11-01

    Full Text Available An efficient and reproducible method for regeneration of commercial and pure lines of tropical butternut squash (Cucurbita moschata plants via somatic embryogenesis was developed. The influence of genotype, explant source, N6-benzylaminopurine (BAP, 2,4-dichlorophenoxyacetic acid (2,4-D and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T concentration on somatic embryogenesis induction was investigated. Friable embryogenic calli was produced from zigotic embryos (53-56% and cotyledons from seedlings (70% of C. moschata cv. Sello de Oro cultured on callus induction medium (CIM supplemented with 0.5 mg/l or 3.5 mg/l 2,4-D. No embryogenic calli was obtained from leaf segments of C. moschata cv. Sello de Oro cultured on CIM supplemented with different concentrations of BAP and 2,4-D and cotyledons from seedlings of C. moschata cv. PVG 04 cultured on CIM with BAP and 2,4,5-T. Embryogenic calli induction was achieved in 75% C. moschata pure lines evaluated and calli percentage frequency range from 5% to 34%. Successful acclimatization of squash in vitro plants was achieved in the greenhouse and in the field. Regenerated plants appeared morphologically normal and set flowers and fruits with seeds that could germinate normally. Rev. Biol. Trop. 57 (Suppl. 1: 119-127. Epub 2009 November 30.

  1. Somatic Embryogenesis and Plant Regeneration from Two Recalcitrant Genotypes of Gossypium hirsutum L.

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-xia; WANG Xing-fen; MA Zhi-ying; ZHANG Gui-yin; HAN Gai-ying

    2006-01-01

    An improved protocol has been developed for somatic embryogenesis and plant regeneration of recalcitrant cotton cultivars. High callus frequencies and embryogenic tissue were developed in MSB medium supplemented with gradient concentrations of KT and 2,4-D, their concentration decreasing from 0.1 to 0.01 mg L-1. Somatic embryos were successfully incubated in 1/2 macronutrient MSB suspension supplemented with 0.5 g L-1 glutamine and 0.5 g L-1 asparagine. Decrease in macronutrient concentration of MSB significantly alleviated browning and was beneficial to suspension cells.Transformation of somatic embryos into plants was induced in MSB medium supplemented with 3% sucrose, 0.5 g L-1 glutamine, 0.5 g L-1 asparagine, and 6.0 g L-1 agar. The effect of sucrose as carbohydrate was better than that of glucose for plant germination. Using this protocol, regenerated plantlets from the CCRI521 and Zhongzhi86-6 reached to as much as 19.6 and 18.5% somatic embryos, respectively.

  2. Influence of plant growth regulators on callus mediated regeneration and secondary metabolites synthesis in Withania somnifera (L.) Dunal.

    Science.gov (United States)

    Chakraborty, Nilanjan; Banerjee, Debarupa; Ghosh, Moumita; Pradhan, Prakash; Gupta, Namrata Shanu; Acharya, Krishnendu; Banerjee, Maitreyi

    2013-01-01

    Withania somnifera (L.) Dunal, is an important medicinal plant being the source of extremely important compounds like withanolides and withaferin. Influence of different plant growth regulators (PGRs) were evaluated for induction of callus, callus mediated regeneration and production of secondary metabolites in them. Explants for callusing were collected from plants grown in vitro and maximum callusing (98 %) was obtained on MS medium supplemented with a combination of 2,4-dichlorophenoxy acetic acid (2,4-D) (0.5 mg l(-1)) and kinetin (KN) (0.2 mg l(-1)). Among different types of calli, best shoot regeneration was observed on green, compact calli produced on MS medium with a combination of 6-benzylamino purine (BAP) and indole butyric acid (IBA). MS medium supplemented with BAP (2 mg l(-1)) showed highest frequency (98 %) of shoot bud regeneration. The micro-shoots were efficiently rooted on MS media supplemented with 0.5 mg l(-1) IBA. Rooted plants were transferred to soil-vermi-compost (1:3; w/w) medium in greenhouse for acclimatization. Presence of withanolide A and withaferin A in calli was validated through high performance thin layer chromatography (HPTLC). It was interesting to observe that the PGRs showed significant influence on the secondary metabolites production in callus and 2,4-D having the least effect. Histological studies revealed the origin of shoot tip in the callus during regeneration.

  3. Efficient callus formation and plant regeneration are heritable characters in sugar beet (Beta vulgaris L.).

    Science.gov (United States)

    Kagami, Hiroyo; Taguchi, Kazunori; Arakawa, Takumi; Kuroda, Yosuke; Tamagake, Hideto; Kubo, Tomohiko

    2016-01-01

    Obtaining dedifferentiated cells (callus) that can regenerate into whole plants is not always feasible for many plant species. Sugar beet is known to be recalcitrant for dedifferentiation and plant regeneration. These difficulties were major obstacles for obtaining transgenic sugar beets through an Agrobacterium-mediated transformation procedure. The sugar beet line 'NK-219mm-O' is an exceptional line that forms callus efficiently and is easy to regenerate, but the inheritance of these characters was unknown. Another concern was whether these characters could coexist with an annual habitat that makes it possible to breed short life-cycle sugar beet suitable for molecular genetic analysis. Five sugar beet lines including NK-219mm-O were crossed with each other and subjected to in vitro culture to form callus. F1s with a NK-219mm-O background generally formed callus efficiently compared to the others, indicating that efficient callus formation is heritable. The regeneration potential was examined based on the phenotypes of calli after placement on regeneration medium. Five phenotypes were observed, of which two phenotypes regenerated shoots or somatic embryo-like structures. Vascular differentiation was evident in regenerable calli, whereas non-regenerable calli lacked normally developed vascular tissues. In a half-diallel cross, the callus-formation efficiency and the regeneration potential of reciprocal F1s progeny having a NK-219mm-O background were high. Finally, we crossed NK-219mm-O with an annual line that had a poor in vitro performance. The callus-formation efficiency and the regeneration potential of reciprocal F1 were high. The regenerated plants showed an annual habitat. Efficient callus formation and the high plant regeneration potential of NK-219mm-O were inherited and expressed in the F1. The annual habitat does not impair these high in vitro performances.

  4. Frequency of injury and the ecology of regeneration in marine benthic invertebrates.

    Science.gov (United States)

    Lindsay, Sara M

    2010-10-01

    Many marine invertebrates are able to regenerate lost tissue following injury, but regeneration can come at a cost to individuals in terms of reproduction, behavior and physiological condition, and can have effects that reach beyond the individual to impact populations, communities, and ecosystems. For example, removal and subsequent regeneration of clams' siphons, polychaetes' segments, and brittlestars' arms can represent significant energetic input to higher trophic levels. In marine soft-sediment habitats, injury changes infaunal bioturbation rates and thus secondarily influences sediment-mediated competition, adult-larval interactions, and recruitment success. The importance of injury and regeneration as factors affecting the ecology of marine invertebrate communities depends on the frequency of injury, as well as on individual capacity for, and speed of, regeneration. A key question to answer is: "How frequently are marine benthic invertebrates injured?" Here, I review the sources and the frequencies of injury in a variety of marine invertebrates from different benthic habitats, discuss challenges, and approaches for accurately determining injury rates in the field, consider evidence for species-specific, temporal and geographic variation in injury rates, and present examples of indirect effects of injury on marine invertebrates to illustrate how injury and regeneration can modify larger-scale ecological patterns and processes.

  5. [Plants regeneration from genetically transformed root and callus cultures of periwinkle Vinca minor L. and foxglove purple Digitalis purpurea L].

    Science.gov (United States)

    Leshina, L G; Bulko, O V

    2014-01-01

    Plants regenerated from hairy roots and calluses of foxglove purple and periwinkle have been obtained. It was found that organogenesis in hairy root culture occurs spontaneously on hormone-free medium but with different efficiencies. The frequency of direct shoot formation from root cultures was up to 60% in Digitalis and 3.7% in Vinca. Addition of 1 mg/l BA, 0.1 mg/l NAA and 5% sucrose to B5 medium increased regenerative capacity of Vinca roots up to 19.1%. Regenerated plants showed morphological features typically seen in Ri-transgenic plants. They include growth and plagiotropism of the root system, increased shoot formation, changed leaf morphology and short internodes.

  6. Pollination and seed dispersal are the most threatened processes of plant regeneration

    Science.gov (United States)

    Neuschulz, Eike Lena; Mueller, Thomas; Schleuning, Matthias; Böhning-Gaese, Katrin

    2016-07-01

    Plant regeneration is essential for maintaining forest biodiversity and ecosystem functioning, which are globally threatened by human disturbance. Here we present the first integrative meta-analysis on how forest disturbance affects multiple ecological processes of plant regeneration including pollination, seed dispersal, seed predation, recruitment and herbivory. We analysed 408 pairwise comparisons of these processes between near-natural and disturbed forests. Human impacts overall reduced plant regeneration. Importantly, only processes early in the regeneration cycle that often depend on plant-animal interactions, i.e. pollination and seed dispersal, were negatively affected. Later processes, i.e. seed predation, recruitment and herbivory, showed overall no significant response to human disturbance. Conserving pollination and seed dispersal, including the animals that provide these services to plants, should become a priority in forest conservation efforts globally.

  7. Plants regenerated from tissue culture contain stable epigenome changes in rice.

    Science.gov (United States)

    Stroud, Hume; Ding, Bo; Simon, Stacey A; Feng, Suhua; Bellizzi, Maria; Pellegrini, Matteo; Wang, Guo-Liang; Meyers, Blake C; Jacobsen, Steven E

    2013-03-19

    Most transgenic crops are produced through tissue culture. The impact of utilizing such methods on the plant epigenome is poorly understood. Here we generated whole-genome, single-nucleotide resolution maps of DNA methylation in several regenerated rice lines. We found that all tested regenerated plants had significant losses of methylation compared to non-regenerated plants. Loss of methylation was largely stable across generations, and certain sites in the genome were particularly susceptible to loss of methylation. Loss of methylation at promoters was associated with deregulated expression of protein-coding genes. Analyses of callus and untransformed plants regenerated from callus indicated that loss of methylation is stochastically induced at the tissue culture step. These changes in methylation may explain a component of somaclonal variation, a phenomenon in which plants derived from tissue culture manifest phenotypic variability. DOI:http://dx.doi.org/10.7554/eLife.00354.001.

  8. Efficient plant regeneration of bittersweet (Solanum dulcamara L., a medicinal plant

    Directory of Open Access Journals (Sweden)

    Arzu Ucar Turker

    2011-04-01

    Full Text Available Solanum dulcamara L. (bittersweet is a medicinal plant that has been used to treat skin diseases, warts, tumors, felons, arthritis, rheumatism, bronchial congestion, heart ailments, ulcerative colitis, eye inflammations, jaundice and pneumonia. A reliable in vitro culture protocol for bittersweet was established. Explants (leaf and petiole segments were cultured on Murashige and Skoog minimal organics (MSMO medium with various plant growth regulator combinations. Leaf explants formed more shoots than petiole explants. Plant regeneration was observed through indirect organogenesis with both explants. Best shoot proliferation was obtained from leaf explants with 3 mg/l BA (benzyladenine and 0.5 mg/l IAA (indole-3-acetic acid. Regenerated shoots were transferred to rooting media containing different levels of IAA (indole-3-acetic acid, IBA (indole-3-butyric acid, NAA (naphthalene acetic acid or 2,4-D (2,4 dichlorophenoxyacetic acid. Most shoots developed roots on medium with 0.5 mg/l IBA. Rooted explants were transferred to vermiculate in Magenta containers for acclimatization and after 2 weeks, they were planted in plastic pots containing potting soil and maintained in the plant growth room.

  9. [Induction of polyploid in hairy roots of Nicotiana tabacum and its plant regeneration].

    Science.gov (United States)

    Hou, Lili; Shi, Heping; Yu, Wu; Tsang, Po Keung Eric; Chow, Cheuk Fai Stephen

    2014-04-01

    By genetic transformation with Agrobacterum rhizogenes and artificial chromosome doubling techniques, we studied the induction of hairy roots and their polyploidization, and subsequent plant regeneration and nicotine determination to enhance the content of nicotine in Nicotiana tabacum. The results show that hairy roots could be induced from the basal surface of leaf explants of N. tabacum 8 days after inoculation with Agrobacterium rhizogenes ATCC15834. The percentage of the rooting leaf explants was 100% 15 days after inoculation. The hairy roots could grow rapidly and autonomously on solid or liquid phytohormones-free MS medium. The transformation was confirmed by PCR amplification of rol gene of Ri plasmid and paper electrophoresis of opines from N. tabacum hairy roots. The highest rate of polyploidy induction, more than 64.71%, was obtained after treatment of hairy roots with 0.1% colchicine for 36 h. The optimum medium for plant regeneration from polyploid hairy roots was MS+2.0 mg/L 6-BA +0.2 mg/L NAA. Compared with the control diploid plants, the hairy roots-regenerated plants had weak apical dominance, more axillary buds and more narrow leaves; whereas the polyploid hairy root-regenerated plants had thicker stems, shorter internodes and the colour, width and thickness of leaves were significantly higher than that of the control. Observation of the number of chromosomes in their root tip cells reveals that the obtained polyploid regenerated plants were tetraploidy, with 96 (4n = 96) chromosomes. Pot-grown experiments showed compared to the control, the flowering was delayed by 21 days in diploid hairy roots-regenerated plants and polyploid hairy root-regenerated plants. GC-MS detection shows that the content of nicotine in polyploid plants was about 6.90 and 4.57 times the control and the diploid hairy roots-regenerated plants, respectively.

  10. [Protoplasts isolation, purification and plant regeneration of Pinellia cordata].

    Science.gov (United States)

    Yang, Xian; Ma, Dan-Dan; Jiang, Fu-Sheng; Chen, Ni-Pi; Ding, Bin; Jin, Li-Xia; Qian, Chao-Dong; Ding, Zhi-Shan

    2014-11-01

    The main factors which affected the isolation, purification and cultivation of Pinellia cordata protoplasts from leaves were studied. The results indicated that the optimum enzyme solution for P. cordata leaves was 13% CPW + 1.0% Cellulose +0.1% Pectolase, at pH 6.0, temperature (25-28 degrees C ) for 4 h. The sucrose density gradient centrifugation was adopted to purificate the protoplasts collected, when 25% sucrose was used as mediator, centrifugating at 500 rpm for 10 min. When the protoplasts were shallow liquid and liquid-solid double layer cultured on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA + 13% mannitol at the density of 2.5 x 104 protoplasts/mL, or fed and nursed cultured at the density of 100-500 protoplasts/mL, cell division could be observed for 3 days; granular calli appeared for 30 days. Calli was proliferated on the medium of MS + 0.5 mg x L(-1) 6-BA + 0.25 mg x L(-1) NAA solidified by 0.55% agar, and differentiated and regenerated after 5-6 months. Plant generation of P. cordata is successfully established.

  11. INFLUENCE OF VITAMIN MORPHOGENESIS REGENERATED PLANTS POTATO IN VITRO TO INTENSIFY PRODUCTION OF ELITE PLANTING MATERIAL

    Directory of Open Access Journals (Sweden)

    E. P. Miakisheva

    2016-08-01

    Full Text Available The paper identifies the need to use the techniques of modern biotechnology in primary seed potatoes in the Russian Federation. At present time, the playback of potatoes does not meet current phytosanitary requirements, moreover, there is a low yield of potatoes in the whole country and the region for a long period of time. The potato yield that annually produced in Russia is much lower than the world's, and does not meet the genetic capabilities of used varieties. Modern methods of biotechnology have undeniable advantages and make it possible to carry out year-round operation for the production of elite planting material of potato. Effective implementation of such activities is provided by careful selection of plant cultivation conditions in vitro, selection of breeding gound and environmental components for each variety in order to provide the maximum parameters of plant growth and productivity. During research we examined the effect of vitamin component of breeding ground according to the formula of  Murashige and Skoog, containing thiamine, pyridoxine, and niacin (the co-enzymes that involved in biochemical reactions of the plants. The effect of vitamin complex on the above-ground plant parts (plant height and number of internodes, as well as indicators of root formation (number and length of roots was studied for regenerated plants of four potato varieties: Adretta, Red Scarlett, Lubava, and Kuznechanka. We proved a positive effect of vitamin component on plant morphogenesis. For each variety we determined the optimal ratio in nutriculture medium.

  12. Esterase as molecular marker for salt tolerance in regenerated plants of rice, Oryza sativa L.

    Science.gov (United States)

    Swapna, T S

    2002-09-01

    Esterase variation was studied in plants regenerated from callus cultures of four rice (Oryza sativa) varieties, viz. pokkali, which is a moderately salt tolerant variety and three salt sensitive varieties MI 48, annapoorna and jyothi. Variation was studied at tillering stage of plants regenerated from callus culture and germinated from seeds. Somaclonal variants for salt tolerance could be detected using variation in esterase banding pattern and activity.

  13. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis

    OpenAIRE

    Monteiro, Mariza; Appezzato-da-Glória, Beatriz; Valarini,Maria José; Oliveira, Carlos Alberto; Vieira, Maria Lucia Carneiro

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  14. Somatic embryogenesis and plant regeneration from immature zygotic embryos of Hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.).

    Science.gov (United States)

    Taniguchi, T; Kurita, M; Itahana, N; Kondo, T

    2004-08-01

    We established a plant regeneration system for Hinoki cypress (Chamaecyparis obtusa) via somatic embryogenesis. Embryogenic tissues were successfully induced on three kinds of Smith media from megagametophyte explants containing pre-cotyledonary embryos of C. obtusa plus-trees. Factors affecting somatic embryo maturation were examined. The concentration of polyethylene glycol 4000 in the medium was a critical factor for embryo maturation and its effective concentration was 150 g/l. The addition of 30 g/l maltose to the medium had a positive effect on embryo maturation, but sucrose was ineffective. The mature somatic embryos germinated at a germination frequency of approximately 60%, and the presence of activated charcoal was effective in stimulating plantlet growth. The plantlets acclimatized successfully in a greenhouse. To our knowledge, this is first report describing details of a plant regeneration method for C. obtusa via somatic embryogenesis.

  15. Induction of Embryogenic Callus and Plant Regeneration in Carnation (Dianthus caryophyllus L.

    Directory of Open Access Journals (Sweden)

    Omid Karami

    2008-01-01

    Full Text Available In this study, efficient plant regeneration through somatic embryogenesis is achieved in four cultivars of carnation (Nelson, Sagres, Spirit and Impulse. Embryogenic calli were induced on petal explants only, all the calli established on leaf, sepal, receptacle and style explants were not embryogenic. Embryogenic calli were obtained on Morashige and Skoog basal medium (1962 containing sucrose 9%, 2.0 mg L-1 2,4-dichlorophenoxy acetic acid (2,4-D, 0.2 mg L-1 6-benzyladenine (BA. After transfer of embryogenic calli to growth regulator free MS medium or medium containing low amount of 2, 4-D (0.2-0.4 mm L-1 resulted in successful somatic embryogenesis. A high frequency (80-85% of Somatic embryo germination and development into normal plantlets was observed on half-strength MS medium supplement with 3% sucrose without growth regulator. About 95% of somatic embryo-derived plantlets were acclimatized in the greenhouse conditions.

  16. Localization of QTLs for in vitro plant regeneration in tomato

    Directory of Open Access Journals (Sweden)

    Nuez Fernando

    2011-10-01

    Full Text Available Abstract Background Low regeneration ability limits biotechnological breeding approaches. The influence of genotype in the regeneration response is high in both tomato and other important crops. Despite the various studies that have been carried out on regeneration genetics, little is known about the key genes involved in this process. The aim of this study was to localize the genetic factors affecting regeneration in tomato. Results We developed two mapping populations (F2 and BC1 derived from a previously selected tomato cultivar (cv. Anl27 with low regeneration ability and a high regeneration accession of the wild species Solanum pennellii (PE-47. The phenotypic assay indicated dominance for bud induction and additive effects for both the percentage of explants with shoots and the number of regenerated shoots per explant. Two linkage maps were developed and six QTLs were identified on five chromosomes (1, 3, 4, 7 and 8 in the BC1 population by means of the Interval Mapping and restricted Multiple QTL Mapping methods. These QTLs came from S. pennellii, with the exception of the minor QTL located on chromosome 8, which was provided by cv. Anl27. The main QTLs correspond to those detected on chromosomes 1 and 7. In the F2 population, a QTL on chromosome 7 was identified on a similar region as that detected in the BC1 population. Marker segregation distortion was observed in this population in those areas where the QTLs of BC1 were detected. Furthermore, we located two tomato candidate genes using a marker linked to the high regeneration gene: Rg-2 (a putative allele of Rg-1 and LESK1, which encodes a serine/threonine kinase and was proposed as a marker for regeneration competence. As a result, we located a putative allele of Rg-2 in the QTL detected on chromosome 3 that we named Rg-3. LESK1, which is also situated on chromosome 3, is outside Rg-3. In a preliminary exploration of the detected QTL peaks, we found several genes that may be related

  17. Generalist birds promote tropical forest regeneration and increase plant diversity via rare-biased seed dispersal.

    Science.gov (United States)

    Carlo, Tomás A; Morales, Juan M

    2016-07-01

    Regenerated forests now compose over half of the world's tropical forest cover and are increasingly important as providers of ecosystem services, freshwater, and biodiversity conservation. Much of the value and functionality of regenerating forests depends on the plant diversity they contain. Tropical forest diversity is strongly shaped by mutualistic interactions between plants and fruit-eating animals (frugivores) that disperse seeds. Here we show how seed dispersal by birds can influence the speed and diversity of early successional forests in Puerto Rico. For two years, we monitored the monthly fruit production of bird-dispersed plants on a fragmented landscape, and measured seed dispersal activity of birds and plant establishment in experimental plots located in deforested areas. Two predominantly omnivorous bird species, the Northern Mockingbird (Mimus polyglottos) and the Gray Kingbird (Tyrannus dominicensis), proved critical for speeding up the establishment of woody plants and increasing the species richness and diversity of the seed rain in deforested areas. Seed dispersal by these generalists increased the odds for rare plant species to disperse and establish in experimental forest-regeneration plots. Results indicate that birds that mix fruit and insects in their diets and actively forage across open and forested habitats can play keystone roles in the regeneration of mutualistic plant-animal communities. Furthermore, our analyses reveal that rare-biased (antiapostatic) frugivory and seed dispersal is the mechanism responsible for increasing plant diversity in the early-regenerating community. © 2016 by the Ecological Society of America.

  18. AtTCTP2, an Arabidopsis thaliana homolog of Translationally Controlled Tumor Protein, enhances in vitro plant regeneration

    Directory of Open Access Journals (Sweden)

    Roberto eToscano-Morales

    2015-07-01

    Full Text Available The Translationally Controlled Tumor Protein (TCTP is a central regulator of cell proliferation and differentiation in animals, and probably also in plants. Arabidopsis harbors two TCTP genes, AtTCTP1 (At3g16640, which is an important mitotic regulator, and AtTCTP2 (At3g05540, which is considered a pseudogene. Nevertheless, we have obtained evidence suggesting that this gene is functional. Indeed, a T-DNA insertion mutant, SALK_045146, displays a lethal phenotype during early rosette stage. Also, both the AtTCTP2 promoter and structural gene are functional, and heterozygous plants show delayed development. AtTCTP1 cannot compensate for the loss of AtTCTP2, since the accumulation levels of the AtTCTP1 transcript are even higher in heterozygous plants than in wild-type plants. Leaf explants transformed with Agrobacterium rhizogenes harboring AtTCTP2, but not AtTCTP1, led to whole plant regeneration with a high frequency. Insertion of a sequence present in AtTCTP1 but absent in AtTCP2 demonstrates that this suppresses the capacity for plant regeneration; also, this phenomenon requires the presence of TCTP (AtTCTP1 or 2 in the nuclei of root cells. This confirms that AtTCTP2 is not a pseudogene and suggests the involvement of certain TCTP isoforms in vegetative reproduction in some plant species.

  19. AtTCTP2, an Arabidopsis thaliana homolog of Translationally Controlled Tumor Protein, enhances in vitro plant regeneration

    Science.gov (United States)

    Toscano-Morales, Roberto; Xoconostle-Cázares, Beatriz; Cabrera-Ponce, José L.; Hinojosa-Moya, Jesús; Ruiz-Salas, Jorge L.; Galván-Gordillo, Santiago V.; Guevara-González, Ramón G.; Ruiz-Medrano, Roberto

    2015-01-01

    The Translationally Controlled Tumor Protein (TCTP) is a central regulator of cell proliferation and differentiation in animals, and probably also in plants. Arabidopsis harbors two TCTP genes, AtTCTP1 (At3g16640), which is an important mitotic regulator, and AtTCTP2 (At3g05540), which is considered a pseudogene. Nevertheless, we have obtained evidence suggesting that this gene is functional. Indeed, a T-DNA insertion mutant, SALK_045146, displays a lethal phenotype during early rosette stage. Also, both the AtTCTP2 promoter and structural gene are functional, and heterozygous plants show delayed development. AtTCTP1 cannot compensate for the loss of AtTCTP2, since the accumulation levels of the AtTCTP1 transcript are even higher in heterozygous plants than in wild-type plants. Leaf explants transformed with Agrobacterium rhizogenes harboring AtTCTP2, but not AtTCTP1, led to whole plant regeneration with a high frequency. Insertion of a sequence present in AtTCTP1 but absent in AtTCTP2 demonstrates that it suppresses the capacity for plant regeneration; also, this phenomenon is enhanced by the presence of TCTP (AtTCTP1 or 2) in the nuclei of root cells. This confirms that AtTCTP2 is not a pseudogene and suggests the involvement of certain TCTP isoforms in vegetative reproduction in some plant species. PMID:26191065

  20. Plant regeneration from petiole segments of some species in tissue culture

    Directory of Open Access Journals (Sweden)

    Krystyna Klimaszewska

    2013-12-01

    Full Text Available The regeneration ability of 21 plant species belonging to 14 families was tested. The method of tissue culture in vitro was applied, on basic MS medium with an addition of growth regulators from the auxin and cytokinin groups. From among the investigated plant groups Peperomia scandens and Caladium × hortulanum were capable of plant regeneration, Passiilora coerulea regenerated shoots, Hedera helix, Begonia glabra, Coleus blumei, Fuchsia hybrida, Passiflora suberosa and Peperomia eburnea formed callus and roots, Kalanchoe blossfeldiana, Pelargonium grandiflorum, P. peltatum, P. radula, Coleus shirensis and Magnolia soulangeana produced callus, Philodendron scandens, Rhododendron smirnovii, Hibiscus rosa-sinensis, Coprosma baueri, Cestrum purpureum and Solanum rantonnetii did not exhibit any regeneration reactions.

  1. Plant Regeneration through Somatic Embryo in Herpetospermum pedunculosum,an Endangered Tibetan Medicinal Herb

    Institute of Scientific and Technical Information of China (English)

    WANG You-wei; LV Xiao-hui; HUANG Bo; YOU Min; WANG Yue-jin; FU Hui-ying; SUN Zong-xi

    2010-01-01

    Objective An effective reproducible protocol for complete plant regeneration via somatic embryogenesis has beendeveloped for Herpetospermum pedunculosum,an endangered Tibetan medicinal herb.Methods The cotyledonexplants used in this study were excised from seedlings germinated in vitro.Callus was induced from cotyledonexplants on Murashige and Skoog's medium,supplemented with 2,4-dichlorophenoxyacetic acid(2,4-D,0.1-1.0mg/L)alone or in combination with 6-benzylaminopurine(BA,0.5,1.0,and 2.0 mg/L).Results The calli showeddifferentiation of globular embryos after three weeks of incubation on MS medium supplemented with variouscombinations of BA and NAA.Sixty-two percent of the embryogenic calli produced somatic embryos in MS basalmedium supplemented with BA(1.0 mg/L)+NAA(2.0 mg/L).The addition of KN(0.5 mg/L)to MS mediumcontaining both BA and NAA(2.0 mg/L each)significantly increased the frequency of somatic embryogenesis.Themaximum percentage of embryogenic calli formation was 83%,and globular embryos formed and germinatedsuccessfully in this medium.Then,transferring the regenerated plants from this medium to hormone-free MSmedium will further enhanced the development of the plants,and the healthy plantlets are formed successfullywithin four weeks.The plantlets were transferred to soil to acclimatize under greenhouse conditions and 75%survived.Conclusion Somatic embryogenesis protocol as reported here can play a key role in the propagation andconservation of this endangered species.

  2. Seed germination and in vitro plant regeneration of Parkia biglobosa ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-05-24

    May 24, 2010 ... To preserve this genetic resource of great economic value, studies on .... The treatments were differentiated by multiple comparison of the averages after ..... related to changes in leaf wax and to xylem regeneration. Hort. Res.

  3. Plant regeneration from stem and petal of carnation (Dianthus caryophyllus L.).

    Science.gov (United States)

    Nugent, G; Wardley-Richardson, T; Lu, C Y

    1991-11-01

    Plants were regenerated via adventitious shoot initiation from petal explants of carnation (Dianthus caryophyllus L.) cultivars Crowley Sim, Ember Rose, Orchid Beauty, Red Sim, White Sim and from stem segments of Crowley Sim, Red Sim, White Sim. Differences in cultivar response were observed, with White Sim being the most responsive for both explant types. Plants were also regenerated from receptacles of this cultivar. The effect of different cytokinins on regeneration from petal and stem explants of cultivar White Sim was compared. Thidiazuron was more effective than 6-benzylaminopurine or kinetin. In stem explants, morphogenic capacity was determined by the developmental stage of the explant. Highest percentage of shoot formation was observed in the youngest stem segments, on all the cytokinins tested. Stem-derived plants grew faster than petal or receptacle-derived plants and produced normal, flowering plants eight to ten months after culture.

  4. Polyamines as biomarkers for plant regeneration capacity: improvement of regeneration by modulation of polyamine metabolism in different genotypes of indica rice.

    Science.gov (United States)

    Shoeb, F; Yadav, J S.; Bajaj, S; Rajam, M V.

    2001-05-01

    The importance of cellular polyamine (PA) levels and the ratio of putrescine (Put) to spermidine (Spd) for plant regeneration ability via somatic embryogenesis in several commercially grown indica rice varieties is reported here. The genotypes namely NDR-624, IR-20, IR-36, BJ-1 (having Put:Spd ratio approximately 2.3) showed superior plant regeneration while KL, PB-1 and TN-1 (having Put:Spd ratio approximately 3.8) showed moderate plant regeneration ability. The genotypes namely HS, Bindli, DV-85, ACB-72, IR-64 and IR-72 (having Put:Spd ratio approximately 5.0) showed poor plant regeneration ability. In contrast KH-7 (Put:Spd ratio approximately 10.0) showed no response at all. Favorable modification of cellular PA titers and their Put:Spd ratio by the addition of exogenous PAs (Put, Spd) or their biosynthesis inhibitor, difluoromethylarginine (DFMA) led to the induction/promotion of plant regeneration in poorly responding genotypes. These results showed a close relationship between cellular PA levels and their Put:Spd ratio with in vitro morphogenetic capacity in indica rice and suggest that the cellular PAs and Put:Spd ratios are important determinants (biomarkers) of plant regeneration ability in indica rice, and the improvement/induction of plant regeneration in morphogenetically poor and recalcitrant species could be achieved by modulating PA metabolism.

  5. Plant Responses to High Frequency Electromagnetic Fields

    Directory of Open Access Journals (Sweden)

    Alain Vian

    2016-01-01

    Full Text Available High frequency nonionizing electromagnetic fields (HF-EMF that are increasingly present in the environment constitute a genuine environmental stimulus able to evoke specific responses in plants that share many similarities with those observed after a stressful treatment. Plants constitute an outstanding model to study such interactions since their architecture (high surface area to volume ratio optimizes their interaction with the environment. In the present review, after identifying the main exposure devices (transverse and gigahertz electromagnetic cells, wave guide, and mode stirred reverberating chamber and general physics laws that govern EMF interactions with plants, we illustrate some of the observed responses after exposure to HF-EMF at the cellular, molecular, and whole plant scale. Indeed, numerous metabolic activities (reactive oxygen species metabolism, α- and β-amylase, Krebs cycle, pentose phosphate pathway, chlorophyll content, terpene emission, etc. are modified, gene expression altered (calmodulin, calcium-dependent protein kinase, and proteinase inhibitor, and growth reduced (stem elongation and dry weight after low power (i.e., nonthermal HF-EMF exposure. These changes occur not only in the tissues directly exposed but also systemically in distant tissues. While the long-term impact of these metabolic changes remains largely unknown, we propose to consider nonionizing HF-EMF radiation as a noninjurious, genuine environmental factor that readily evokes changes in plant metabolism.

  6. Tissue culture-induced DNA methylation polymorphisms in repetitive DNA of tomato calli and regenerated plants.

    Science.gov (United States)

    Smulders, M J; Rus-Kortekaas, W; Vosman, B

    1995-12-01

    The propagation of plants through tissue culture can induce a variety of genetic and epigenetic changes. Variation in DNA methylation has been proposed as a mechanism that may explain at least a part of these changes. In the present study, the methylation of tomato callus DNA was compared with that of leaf DNA, from control or regenerated plants, at MspI/HpaII sites around five middle-repetitive sequences. Although the methylation of the internal cytosine in the recognition sequence CCGG varied from zero to nearly full methylation, depending on the probe used, no differences were found between callus and leaf DNA. For the external cytosine, small differences were revealed between leaf and callus DNA with two probes, but no polymorphisms were detected among DNA samples of calli or DNA samples of leaves of regenerated plants. When callus DNA cut with HindIII was studied with one of the probes, H9D9, most of the signal was found in high-molecular-weight DNA, as opposed to control leaf DNA where almost all the signal was in a fragment of 530 bp. Also, an extra fragment of 630 bp was found in the callus DNA that was not present in control leaf DNA. Among leaves of plants regenerated from tissue culture, the 630-bp fragment was found in 10 of 68 regenerated plants. This 630-bp fragment was present among progeny of only 4 of these 10 plants after selfing, i.e. it was partly inherited. In these cases, the fragment was not found in all progeny plants, indicating heterozygosity of the regenerated plants. The data are interpreted as indicating that a HindIII site becomes methylated in callus tissue, and that some of this methylation persists in regenerated plants and is partly transmitted to their progeny.

  7. Regeneration of plants from callus tissues of hairy roots induced by Agrobacterium rhizogenes on Alhagi pseudoalhagi

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The legume forage Alhagi pseudoalhagi was transformed by the Agrobacterium rhizogenes strain A4 using cotyledon and hypocotyl segments as infection materials. Regenerated plants were achieved from sterile calli derived from hairy roots, which occurred at or near the infection sites. The regenerated plants from hairy root were characterized by normal leaf morphology and stem growth but a shallow and more extensive root system than normal plants. Opine synthesis, PCR and Southern blot confirmed that TDNA had been integrated into the A. pseudoalhagi genome. Acetosyringone (AS) was found to be vital for successful transformation of A. pseudoalhagi.

  8. Efficient plant regeneration from cotyledon explants of bottle gourd (Lagenaria siceraria Standl.).

    Science.gov (United States)

    Han, J-S; Oh, D-G; Mok, I-G; Park, H-G; Kim, C K

    2004-11-01

    Using cotyledon explants excised from seedlings germinated in vitro, an efficient plant regeneration system via organogenesis was established for bottle gourd (Lagenaria siceraria Standl.). Maximum shoot regeneration was obtained when the proximal parts of cotyledons from 4-day-old seedlings were cultured on MS medium with 3 mg/l BA and 0.5 mg/l AgNO(3) under a 16-h photoperiod. After 3-4 weeks of culture, 21.9-80.7% of explants from the five cultivars regenerated shoots. Adventitious shoots were successfully rooted on a half-strength MS medium with 0.1 mg/l IAA for 2-3 weeks. Flow cytometric analysis revealed that most of the regenerated plants derived from culture on medium with AgNO(3) were diploid.

  9. Development of an efficient plant regeneration protocol for sweet ...

    African Journals Online (AJOL)

    UKZN

    2012-10-18

    Oct 18, 2012 ... Key words: Tissue culture, regeneration, sweet potato, genetic transformation. INTRODUCTION ... from different cultivars with varying levels of ... The pH was adjusted to 5.8 with NaOH prior to autoclaving at. 121°C for 20 min.

  10. Agrobacterium tumefaciens-mediated transformation of embryogenic tissue and transgenic plant regeneration in Chamaecyparis obtusa Sieb. et Zucc.

    Science.gov (United States)

    Taniguchi, T; Kurita, M; Ohmiya, Y; Kondo, T

    2005-03-01

    A genetic transformation procedure for Chamaecyparis obtusa was developed after co-cultivation of embryogenic tissues with disarmed Agrobacterium tumefaciens strain C58/pMP90, which harbours the sgfp (synthetic green fluorescent protein) visual reporter and nptII (neomycin phoshotransferase II) selectable marker genes. The highest transformation frequency was 22.5 independent transformed lines per dish (250 mg embryogenic tissue) following selection on kanamycin medium. Transgenic plantlets were regenerated through the maturation and germination of somatic embryos. The intensity of GFP fluorescence, observed under a fluorescence microscope, varied from very faint to relatively strong, depending on the transgenic line or part of the transgenic plant. The integration of the genes into the genome of regenerated plantlets was confirmed by Southern blot analysis.

  11. Derepression of the plant Chromovirus LORE1 induces germline transposition in regenerated plants.

    Directory of Open Access Journals (Sweden)

    Eigo Fukai

    2010-03-01

    Full Text Available Transposable elements represent a large proportion of the eukaryotic genomes. Long Terminal Repeat (LTR retrotransposons are very abundant and constitute the predominant family of transposable elements in plants. Recent studies have identified chromoviruses to be a widely distributed lineage of Gypsy elements. These elements contain chromodomains in their integrases, which suggests a preference for insertion into heterochromatin. In turn, this preference might have contributed to the patterning of heterochromatin observed in host genomes. Despite their potential importance for our understanding of plant genome dynamics and evolution, the regulatory mechanisms governing the behavior of chromoviruses and their activities remain largely uncharacterized. Here, we report a detailed analysis of the spatio-temporal activity of a plant chromovirus in the endogenous host. We examined LORE1a, a member of the endogenous chromovirus LORE1 family from the model legume Lotus japonicus. We found that this chromovirus is stochastically de-repressed in plant populations regenerated from de-differentiated cells and that LORE1a transposes in the male germline. Bisulfite sequencing of the 5' LTR and its surrounding region suggests that tissue culture induces a loss of epigenetic silencing of LORE1a. Since LTR promoter activity is pollen specific, as shown by the analysis of transgenic plants containing an LTR::GUS fusion, we conclude that male germline-specific LORE1a transposition in pollen grains is controlled transcriptionally by its own cis-elements. New insertion sites of LORE1a copies were frequently found in genic regions and show no strong insertional preferences. These distinctive novel features of LORE1 indicate that this chromovirus has considerable potential for generating genetic and epigenetic diversity in the host plant population. Our results also define conditions for the use of LORE1a as a genetic tool.

  12. Stimulation of somatic embryogenesis and plant regeneration from anther culture of Vitis vinifera cv. Cabernet-Sauvignon.

    Science.gov (United States)

    Cl Mauro, M; Nef, C; Fallot, J

    1986-10-01

    Somatic embryogenesis and subsequent diploid plants have been obtained from anthers of Vitis vinifera Cabernet-Sauvignon, a cultivar so far considered as recalcitrant to in vitro regeneration. Anthers enclosing microspores near the first pollen mitosis were found to be the most responsive. However, from a practical point of view anther length proved to be an easier criterium for determining the optimal physiological anther stage. Calli derived from the anther somatic tissues produced embryoids only when cultured on a medium supplemented with casein hydrolysate. Glutamine and adenine were found to stimulate this embryoid production. Evidence is presented that early removal of cotyledons increases the frequency of normal development of embryoids into plantlets.

  13. Callus induction and plant regeneration from mature bluegrass (Poa pratensis L.) seeds

    Institute of Scientific and Technical Information of China (English)

    Sun Bi-po; Zhang Wan-jun; Dong Jiang-li; Jin Yong-sheng; Wang Tao

    2006-01-01

    A protocol was discussed for high efficient plant regeneration from seven bluegrass (Poa pratensis L.) cultivars via an indirect callus induction and somatic embryogenesis method. Mature seeds were used as explants for callus initiation. Callus induction and proliferation efficiencies were investigated on NB, modified MS (MMS) and MS media, supplemented with 2.0 mg.L-12,4-dichlorophenoxyacetic acid (2,4-D). The MMS medium performed best. Based on the MMS medium, direct and indirect callus the direct callus induction method, the most suitable 2,4-D concentrations varied among cultivars. Under the indirect callus induction method, a significantly high callus induction frequency (93.33%-98.33%) was obtained and there were barely any statistically significant differences among the tested genetically diverse cultivars. Somatic embryos were promoted on the MMS medium supplemedium containing different concentrations of thidiazuron (TDZ), and the differentiation frequencies varied in the range from 20.15% to 77.65%. The 0.25 mg·L-1 TDZ was generally the most suitable concentration for the tested cultivars.

  14. [Induction of polyploid hairy roots and its plant regeneration in Pogostemon cablin].

    Science.gov (United States)

    Shi, Heping; Yu, Wu; Zhang, Guopeng; Tsang, Pokeung Eric; Chow, Cheuk Fai Stephen

    2014-08-01

    Abstract: In order to enhance the content of secondary metabolites patchouli alcohol in Pogostemon cablin, we induced polyploid hairy roots and their plant regeneration, and determined the content of patchouli alcohol through artificial chromosome doubling with colchicine. The highest rate of polyploidy induction was more than 40% when hairy roots were treated with 0.05% colchicine for 36 h. The obtained polyploid hairy roots formed adventitious shoots when cultured in an MS medium with 6-BA 0.2 mg/L and NAA 0.1 mg/L for 60 d. Compared with the control diploid plants, the polyploid hairy root-regenerated plants of P. cablin had more developed root systems, thicker stems, shorter internodes and longer, wider and thicker leaves. Observation of the chromosome number in their root tip cells reveals that the obtained polyploid regenerated plants were tetraploidy, with 128 (4n = 128) chromosomes. The leaves contained around twice as many stomatal guard cells and chloroplasts as the controls, but the stomatal density declined with increasing ploidy. The stomatal density in diploid plants was around 1.67 times of that in polyploid plants. GC-MS analysis shows that the content of patchouli alcholol in the hairy root-derived polyploid plants was about 4.25 mg/g dry weight, which was 2.3 times of that in diploid plants. The present study demonstrates that polyploidization of hairy roots can stimulate the content of patchouli alcholol in medicinal plant of P. cablin.

  15. Regeneration and growth rates of allofragments in four common stream plants

    DEFF Research Database (Denmark)

    Riis, Tenna; Madsen, Tom Vindbæk; Sennels, R. S. H.

    2009-01-01

    Colonisation by stream plants occurs to a large extent from simple stem fragments. Allofragments are stem fragments formed by mechanical breakage. We studied regeneration, colonisation, and growth rates in four common stream plants: Elodea canadensis Michx., Myriophyllum spicatum L., Potamogeton...... perfoliatus L. and Ranunculus baudotii x pseudofluitans. The objectives of this study were to determine (1) if shoots with an apical tip have higher regeneration (growth of new shoots and rhizomes from allofragments) and colonisation (root attachment in sediment) abilities and higher relative growth rates...

  16. Regeneration of fertile plants from isolated tobacco zygotes by in vitro culture

    Institute of Scientific and Technical Information of China (English)

    HE Yuchi; SUN Mengxiang; YANG Hongyuan

    2004-01-01

    Living zygotes of tobacco (Nicotiana Tabacum L.) SR-1 were isolated and cultured in vitro by the microculture technique. Fertile plants were regenerated from the calli derived from cultured zygotes via organogenesis. Ovules were collected 120 h after pollination and used as feeder. MS combined with KM8p was selected as basic medium in the experiment. Zygotes isolated from ovules 108 h after pollination turned out to be suitable material for in vitro culture. Over 80% such zygotes could divide and around 10% of them could grow into calli and regenerate fertile plants.

  17. Agrobacterium tumefaciens-mediated transgenic plant and somaclone production through direct and indirect regeneration from leaves in Stevia rebaudiana with their glycoside profile.

    Science.gov (United States)

    Khan, Shamshad Ahmad; Ur Rahman, Laiq; Shanker, Karuna; Singh, Manju

    2014-05-01

    Agrobacterium tumefaciens (EHA-105 harboring pCAMBIA 1304)-mediated transgenic plant production via direct regeneration from leaf and elite somaclones generation through indirect regeneration in Stevia rebaudiana is reported. Optimum direct regeneration frequency along with highest transformation frequency was found on MS + 1 mg/l BAP + 1 mg/l NAA, while indirect regeneration from callus was obtained on MS + 1 mg/l BAP + 2 mg/l NAA. Successful transfer of GUS-positive (GUS assay and PCR-based confirmation) transgenic as well as four somaclones up to glasshouse acclimatization has been achieved. Inter-simple sequence repeat (ISSR) profiling of transgenic and somaclonal plants showed a total of 113 bands, out of which 49 were monomorphic (43.36 %) and 64 were polymorphic (56.64 %). Transgenic plant was found to be closer to mother plant, while on the basis of steviol, stevioside, and rebaudioside A profile, somaclone S2 was found to be the best and showed maximum variability in ISSR profiling.

  18. Breeding and Simple-rapid Regeneration Protocol for Jisheng 1 with Glandless Trait and High-frequency Somatic Embryo Production Ability

    Institute of Scientific and Technical Information of China (English)

    LI Wei-ming; ZHANG Han-shuang; ZHAO Jun-li; SUN Jing-yan

    2008-01-01

    @@ Most of model cotton varieties used in tissue culture have glands on both the reproductive and vegetative parts of the plant.These glands contain compounds that are toxic to human and non-ruminant animals.The presence of these compounds limits their usage as food and feed.To obtain a glandless cotton variety with high-frequency somatic embryo production ability,27 glandless varieties were screened in improved MSB media containing 0.1 mg · L-1 IAA,0.1 mg · L-1 KT,and 0.1 mg · L-1 2,4-D.Hengwu 8930,whose regeneration rate was only 2.5%,and the cycle of regeneration was about 12 months had the highest frequency.

  19. Plant regeneration from hypocotyl protoplasts of winter oilseed rape (Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Wacław Orczyk

    2014-01-01

    Full Text Available Protoplasts were isolated from hypocotyls of six breeding lines and two cultivars of winter oilseed rape (B. napus L.. Under presented culture conditions almost all of the protoplasts regenerated cell walls. Division frequency depended on the genotype and was from 50% to 64%. Shoot regeneration (also depended on the genotype was induced with the frequency of 3.6% (for cv Bolko on the medium containing IAA (0.1 mg•dm-3, zeatin (0.5 mg•dm-3 and BAP (0.5 mg•dm-3 . All shoots were rooted on MS basal medium supplemented with sucrose 30 g•dm-3.

  20. Plant regeneration from mesophyll protoplast of indica rice Qiugui'ai 11 (Oryza sativa L.)

    Institute of Scientific and Technical Information of China (English)

    JIANYuyu; JintaanankulSuwan

    1998-01-01

    In the recent decade, plant regeneration from protoplast has been obtained through embryogenic cell suspension cultures of rice. However, not only the establishment of embryogenic call suspension cultures of rice was difficult, but also the protoplasts became less and less regenerable and the genetic change was gradu ally accumulated during the prolonged culture.Since 1976 (Deka.), extensive efforts have been made to induce sustained division and regenerate plants from rnesophyll protoplasts of rice, but not successful.

  1. Construction of plant expression vectors carrying glnA gene encoding glutamine synthetase and regeneration of transgenic rice plants

    Institute of Scientific and Technical Information of China (English)

    苏金; 张雪琴; 颜秋生; 陈章良; 尤崇杓

    1995-01-01

    The glnA gene encoding glutamine synthetase (GS) was amplified from Azospirillum brasilenseSp7 with PCR technique.The amplified 1.4-kb DNA fragment flanked with a BamH Ⅰ site at each end wascloned into EcoR V site of Bluescript-SK vector.A recombinant plasmid pGSJ1 containing this 1.4-kb DNA frag-ment was selected by restriction digestion analysis.The sequencing data also confirmed that the amplified 1.4-kbDNA fragment was undoubtedly the glnA gene of A.brasilense Sp7.Then the 1.4-kb BamH Ⅰ fragment was ex-cised from pGSJ1.A glnA plant expression vector pAGNB92 with rice actin 1 (Act1) promoter was constructedby using colony in situ hybridization to screen positive clones,and 3 rounds of ligation and transformation wereperformed.Protoplasts isolated from rice (Oryza sativa,L.Japonica) cell suspension line (cv.T986) weretransformed with the glnA plant expression vector pAGNB92 carrying neomycin phosphotransferase Ⅱ (NPT Ⅱ)gene by PEG fusion or electroporation.G418~ calli were used to detect NPT Ⅱ enzyme activity.The resultsshow that G418~ calli possess high positive hybridization signal with the frequency of 37%.The regeneratedG418~NPTII~+ rice plants were used for PCR amplification of glnA gene,and a 1.4-kb DNA fragment was ampli-fied from glnA-transgenic rice plants (R0 generation).The results of Southern blot hybridization prove that the1.4-kb DNA fragment amplified from the total DNA of glnA transgenic rice plants is indeed the glnA gene of A.brasilense Sp7.Northern blot hybridization was carried out using the same glnA gene as probe.The glnAgene was expressed in the transgenic rice plants.Bioassays also confirmed that the glnA transgenic rice plantsgrew much better than that of the control plants under a condition with nitrogen poor source (0.75 mmol/L).

  2. Factors Affecting Embryogenic Callus Production and Plant Regeneration in Anther Culture of Bupleurum chinense

    Institute of Scientific and Technical Information of China (English)

    YANG Cheng-min; ZHAO Yu-kai; WEI Jian-he; ZHAO Li-zi; SUI Chun; ZHANG Zheng; CUI Lu-ying

    2011-01-01

    Objective To evaluate the influences of the genotypes,anther developmental stages,and cultural conditions on the efficiency of embryogenic callus induction and plant regeneration in the anthers culture of Bupleurum chinense.Methods The different effects such as four genotypes,plant growth regulators,and temperature condition were compared in the experiments.The histological study was performed with the process of the anther culture.Results The highest inducing rate of embryogenic calli were achieved for the genotypes Zhongcaiyihao(ZCYH),Z4,and Z5 at the early-to middle-uninucleate stages,except for genotype ZPM1 at the tetrad stage.Cold pretreatment increased the production of the embryogenic callus,in which 4-day cold pretreatment improved the production of embryogenic callus from 0% to 2.2% and 5.0% for genotypes ZPM1 and ZCYH,respectively.No embryogenic callus was induced in the medium containing less than 0.75 mg/L 2,4-dichlorophenoxyacetic acid(2,4-D).The highest regeneration rate (34.6%)was obtained in 1/2 MS salts regeneration medium supplemented with 0.1 mg/L 6-benzylmaminopurine (BA).The low concentration of BA was able to promote the embryogenic callus formation and subsequent plantlet regeneration via somatic embryogenesis.Chromosome counting of regenerated plantlets showed mostly diploid plant (2n = 12)with only one haploid plant(n = 6).Because of the low rate of microspore embryo formation,we only tracked the process of embryogenesis from the connective tissue,instead of microspore by histological observations.Conclusion This study establishes an efficient system for embryogenic callus induction and plant regeneration system.This is the first report on the haploid plantlet through the anther culture orB.chinense.

  3. Study on Plant Regeneration of Wheat Mature Embryos Under Endosperm-Supported Culture

    Institute of Scientific and Technical Information of China (English)

    CHEN Jun-ying; YUE Run-qing; XU Hai-xian; CHEN Xin-jian

    2006-01-01

    To reveal the suitability of using mature embryos as an explant source in wheat tissue culture, mature embryos from eight common wheat cultivars (Triticum aestivum L. cv.) were cultured with or without endosperm to test their efficiency of callus induction and plant regeneration. When embryos were cultured together with endosperm (endosperm-supported culture, ES), the percentage of callus induction was significantly lower than that when embryos were cultured in the absence of endosperm (non-endosperm-supported culture, NES). This pattern was evident in most genotypes, regardless of whether 2 or 8 mg L-1 2,4-D was added in the NES culture. However, in ES culture, more induced calli were differentiated into distinct green spots and they further developed into plantlets. Thus, more plants were regenerated in ES culture than in the NES treatment. Most of the eight tested genotypes showed a significant difference in callus induction rate and plantlet regeneration in both ES and NES cultures. In addition, the enzymatic activity of oxalate oxidase in the callus of ES culture condition was obviously higher than that in the callus of NES culture condition, suggesting that the activity of oxalate oxidase may be a parameter for selection of calli with potential for plantlet regeneration. These results indicate that wheat mature embryos are valuable explants for highly efficient callus induction and plant regeneration, if proper treatment and medium are used.

  4. Ion Frequency Landscape in Growing Plants.

    Directory of Open Access Journals (Sweden)

    Mariusz Pietruszka

    Full Text Available It has been interesting that nearly all of the ion activities that have been analysed thus far have exhibited oscillations that are tightly coupled to growth. Here, we present discrete Fourier transform (DFT spectra with a finite sampling of tip-growing cells and organs that were obtained from voltage measurements of the elongating coleoptiles of maize in situ. The electromotive force (EMF oscillations (~ 0.1 μV were measured in a simple but highly sensitive resistor-inductor circuit (RL circuit, in which the solenoid was initially placed at the tip of the specimen and then was moved thus changing its position in relation to growth (EMF can be measured first at the tip, then at the sub-apical part and finally at the shank. The influx- and efflux-induced oscillations of Ca2+, along with H+, K+ and Cl- were densely sampled (preserving the Nyquist theorem in order to 'grasp the structure' of the pulse, the logarithmic amplitude of pulse spectrum was calculated, and the detected frequencies, which displayed a periodic sequence of pulses, were compared with the literature data. A band of life vital individual pulses was obtained in a single run of the experiment, which not only allowed the fundamental frequencies (and intensities of the processes to be determined but also permitted the phase relations of the various transport processes in the plasma membrane and tonoplast to be established. A discrete (quantised frequency spectrum was achieved for a growing plant for the first time, while all of the metabolic and enzymatic functions of the life cell cycle were preserved using this totally non-invasive treatment.

  5. Regeneration of Dioscorea floribunda plants from cryopreserved encapsulated shoot tips: effect of plant growth regulators.

    Science.gov (United States)

    Mandal, B B; Ahuja-Ghosh, Sangeeta

    2007-01-01

    The encapsulation-dehydration protocol for the cryopreservation of in vitro shoot tips of Dioscorea floribunda was optimized. Maximum survival of 87% was obtained when overnight pretreatment with 0.3 M sucrose was followed by encapsulation, preculture in 0.75 M sucrose for 4 d, dehydration in a laminar air flow for 5.5 h, quenching in liquid nitrogen and thawing at 40 degrees C. During recovery growth, 29% shoot formation was obtained when cryopreserved shoot tips were initially cultured for 25 d on a medium with 1.5 mg per liter (-1) BAP, 0.2 mg per liter(-1) NAA and 0.2 mg per liter(-1) GA3 followed by culturing for 15 d on a medium with reduced BAP (1 mg per liter(-1)) but increased NAA (0.5 mg per liter(-1)) and GA3 (0.3 mg per liter(-1)). Finally, transfer on to a medium with further reduced doses of BAP (0.05 mg per liter(-1)) and NAA (0.15 mg per liter(-1)) but without GA3 stimulated production of fully grown plantlets. All plants regenerated without callus formation. Modification of post-thaw culture media with plant growth regulators was essential for regrowth of shoot tips to plantlets.

  6. Plant regeneration through somatic embryogenesis from callus induced on immature embryos of Alstroemeria spp. L.

    Science.gov (United States)

    Van Schaik, C E; Posthuma, A; De Jeu, M J; Jacobsen, E

    1996-01-01

    The plant regeneration ability of callus obtained from zygotic embryos of the monocot Alstroemeria spp. was studied. The best explants for somatic embryogenesis were immature zygotic embryos in half-ovules when the endosperm was still soft and white. For 2 genotypes embryogenic callus was induced on callus induction medium with a success rate of 54%. The best callus induction period was 10 weeks. The morphology of embryogenic callus was nodular. Somatic embryos were formed after transfer of the callus to regeneration medium. These somatic embryos revealed later on the typical features of zygotic Alstroemeria embryos. The total duration of the plant regeneration protocol, from inoculation till rooted plantlets ready for transfer to the greenhouse, was 28 weeks.

  7. The frequency dependent regenerator cold section and hot section positional reversal in a coaxial type thermoacoustic Stirling heat pump

    Science.gov (United States)

    Widyaparaga, Adhika; Koshimizu, Takao; Noda, Eiji; Sakoda, Naoya; Kohno, Masamichi; Takata, Yasuyuki

    2011-10-01

    We have constructed and tested two travelling wave thermoacoustic heat pumps using a coaxial configuration with the regenerator positioned in the annulus. We discovered a frequency dependent positional reversal of the cold section and hot section of the regenerator within the test frequency range. By decomposing the measured pressure wave within the annulus, we obtained the positive ( w+) and negative ( w-) propagating travelling waves. It has been revealed the change of frequency is accompanied by a change in magnitudes of w+ and w- which is in part influenced by the presence of travelling wave attenuation through the regenerator. The resulting change of dominant travelling wave on a given end of the regenerator will then change the direction of thermoacoustic heat pumping at that end. This will alter the regenerator temperature distribution and may reverse the cold and hot sections of the regenerator. As the reversal does not require additional moving parts, merely a change in frequency, this feature in coaxial travelling wave devices has tremendous potential for applications which require both heating and cooling operation.

  8. Plant regeneration from somatic embryos ofTaxus brevifolia.

    Science.gov (United States)

    Chee, P P

    1996-12-01

    Taxusbrevifolia is the source of paclitaxel (Taxol®), an anticancer drug. A method for regeneration ofTaxus brevifolia from immature zygotic embryos via somatic embryogenesis is described. Embryogenic callus tissues were obtained by culturing immature zygotic embryos on Lloyd and McCown medium (MCM) supplemented with 160 μM 2,4-dichlorophenoxyacetic acid (2,4-D) + 5 μM benzylaminopurine (BA) + 5 μM naphthaleneacetic acid (NAA) for 4 weeks. Putative embryoids were obtained following transfer of cultures to MCM medium supplemented with 4 μM BA + 5 μM kinetin + 1 μM NAA for 6 to 8 weeks. Conversion of embryos was obtained on MCM medium supplemented with 40 μM abscisic acid (ABA) + 1% activated charcoal. Development of bipolar structures with recognizable shoot and root apices was observed in somatic embryos. Five percent of somatic embryos were regenerated into plantlets on half-strength growth regulator-free MCM medium.

  9. Regeneration of fertile plants from protoplasts of soybean (Glycine max L. Merr.): genotypic differences in culture response.

    Science.gov (United States)

    Dhir, S K; Dhir, S; Widholm, J M

    1992-06-01

    Fourteen soybean (Glycine max L.) genotypes were evaluated for their regenerability from protoplasts using a procedure previously descibed for the cultivar Clark 63. Protoplasts were isolated from immature cotyledon tissue and were cultured in liquid or agarose gelled KP8, MS or B5 medium with different sugars. Significant differences were observed in plating efficiency, which was as high as 63% in Jack and A-2396, and as low as 38% in X-3337. Upon regular dilution with K8 medium, 1-2 mm diameter colonies were formed in 5-6 weeks with all the genotypes tested. These colonies were then transferred onto MSB (MS salts; Murashige & Skoog, 1962 + B5 organics; Gamborg et al., 1968) medium with 0.5 mg l(-1) each of 2,4-D, BA and KN and 500 mg l(-1) CH for further growth. Once the colonies had become green, compact and nodular, and were 8-10 mm in size, they were transferred to regeneration medium. Upon regular subculturing, calli of six genotypes; A-2396, Chamberlain, Heilong-26, Jack, Resnick and XP-3015 developed shoots, with the regeneration frequency being highest 27% in Jack (52 calli out of 192 produced 8-12 shoots). The regenerated shoots from different genotypes were elongated and rooted. So far, sixty three complete plants have been obtained, including twelve A-2396, nineteen Chamberlain, fifteen Jack, nine Resnick and eight XP-3015. A total of thirty five plants have been transplanted into pots in the greenhouse. Sixteen have set seeds and others are producing flowers and pods.

  10. High capacity of plant regeneration from callus of interspecific hybrids with cultivated barley (Hordeum vulgare L.)

    DEFF Research Database (Denmark)

    Bagger Jørgensen, Rikke; Jensen, C. J.; Andersen, B.

    1986-01-01

    Callus was induced from hybrids between cultivated barley (Hordeum vulgare L. ssp. vulgare) and ten species of wild barley (Hordeum L.) as well as from one backcross line ((H. lechleri .times. H. vulgare) .times. H. vulgare). Successful callus induction and regeneration of plants were achieved from...

  11. Effect of Salicylic Acid on Somatic Embryogenesis and Plant Regeneration in Hedychium bousigonianum

    Science.gov (United States)

    The objective of this study was to induce somatic embryogenesis in Hedychium bousigonianum Pierre ex Gagnepain and assess the influence of salicylic acid (S) on somatic embryogenesis. Somatic embryos and subsequently regenerated plants were successfully obtained 30 days after transfer of embryogenic...

  12. Callus induction and plant regeneration from different explant types of Miscanthus x ogiformis Honda 'Giganteus'

    DEFF Research Database (Denmark)

    Holme, Inger Bæksted; Petersen, Karen Koefoed

    1996-01-01

    . The explants were cultured on urashige and Skoog medium supplemented with 4.5, 13.6, 22.6 or 31.7 μM 2,4-dichlorophenoxyacetic acid. Three types of callus were formed but only one was embryogenic and regenerated plants. Callus induction and formation of embryogenic callus depended on the type and developmental...

  13. Prolific plant regeneration from protoplast-derived tissues of Lotus corniculatus L. (birdsfoot trefoil).

    Science.gov (United States)

    Ahuja, P S; Hadiuzzaman, S; Davey, M R; Cocking, E C

    1983-04-01

    Protoplasts isolated enzymatically from seedling roots, hypocotyls and cotyledons of Lotus corniculatus L. produced callus which underwent prolific shoot regeneration. The rapidity and ease of recovering plants from protoplast-derived tissues makes this forage legume an attractive experimental system for genetic manipulation.

  14. Isolation of protoplasts and culture and regeneration into plants in Alstroemeria

    NARCIS (Netherlands)

    Kim, J.B.; Bergervoet-van Deelen, J.E.M.; Raemakers, C.J.J.M.; Jacobsen, E.; Visser, R.G.F.

    2005-01-01

    An efficient system for the regeneration of plants from protoplasts was developed in Alstroemeria. Friable embryogenic callus (FEC) proved to be the best source for protoplast isolation and culture when compared with leaf tissue and compact embryogenic callus. Protoplast isolation was most efficient

  15. High–frequency in vitro plantlet regeneration from apical bud as a novel explant of Carum copticum L.

    Directory of Open Access Journals (Sweden)

    Mansoureh Salehi

    2014-05-01

    Conclusion: In this study, a simple and reliable regeneration and acclimatization protocol for Carum copticum has been presented. This protocol can be found very advantageous for a variety of purposes, including mass multiplication of Carum species, medicinal plant breeding studies and transgenic plant production.

  16. Plant Regeneration from In Vitro Cultured Hypocotyl Explants of Euonymus japonicus Cu zhi

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Adventitious shoots were successfully regenerated from hypocotyl explants of in vitro cultures of Euonymus japonicus Cu zhi. Hypocotyl slices were cultured on Murashige and Skoog (MS) and B5 basal medium supplemented with varied concentration of different plant growth-regulators, e.g., α-naphthaleneacetic acid (NAA) and indole-3-butyric acid (IBA) in combination with 6-benzylaminopurine (6-BA) and kinetin. The study showed that shoots could be directly regenerated from hypocotyl explants without the intervening callus phase; MS medium was more suitable for adventitious shoots regeneration. The ability of hypocotyls segments to produce shoots varied depending upon their position on the seedlings. The highest regeneration rate was obtained with hypocotyl segments near to the cotyledon cultured on MS basal medium supplemented with 1.5 mg L-1 6-BA and 0.05 mg L-1 NAA (63.64%). The regenerated shoots were readily elongated on the same medium as used for multiplication and rooted on half-strength MS basal medium supplemented with 1.0 mg L-1 IBA and 100 mg L-1 activated carbon. After being transferred to greenhouse conditions, 96% of the plantlets were successfully acclimatized. This regeneration system is applied for genetic transformation now.

  17. Factors influencing callus induction and plant regeneration of ...

    African Journals Online (AJOL)

    ajl yemi

    2012-01-12

    Jan 12, 2012 ... order to optimize the callus induction and plant rege- neration from ... To determine the role of basal medium for callus induction and plant .... Chu CC, Wang CS, Sun CC, Hsu C, Yin KC, Chu CY, Bi FY (1975). Establishment of ...

  18. Regeneration of Centella asiatica plants from non-embryogenic cell lines and evaluation of antibacterial and antifungal properties of regenerated calli and plants

    Directory of Open Access Journals (Sweden)

    Habib Darima

    2011-10-01

    Full Text Available Abstract Background The threatened plant Centella asiatica L. is traditionallyused for a number of remedies. In vitro plant propagation and enhanced metabolite production of active metabolites through biotechnological approaches has gained attention in recent years. Results Present study reveals that 6-benzyladenine (BA either alone or in combination with 1-naphthalene acetic acid (NAA supplemented in Murashige and Skoog (MS medium at different concentrations produced good quality callus from leaf explants of C. asiatica. The calli produced on different plant growth regulators at different concentrations were mostly embryogenic and green. Highest shoot regeneration efficiency; 10 shoots per callus explant, from non-embryogenic callus was observed on 4.42 μM BA with 5.37 μM NAA. Best rooting response was observed at 5.37 and 10.74 μM NAA with 20 average number of roots per explant. Calli and regenerated plants extracts inhibited bacterial growth with mean zone of inhibition 9-13 mm diameter when tested against six bacterial strains using agar well diffusion method. Agar tube dilution method for antifungal assay showed 3.2-76% growth inhibition of Mucor species, Aspergillus fumigatus and Fusarium moliniformes. Conclusions The present investigation reveals that non-embryogenic callus can be turned into embryos and plantlets if cultured on appropriate medium. Furthermore, callus from leaf explant of C. asiatica can be a good source for production of antimicrobial compounds through bioreactor.

  19. Structural and functional organisation of regenerated plant protoplasts exposed to microgravity on Biokosmos 9

    Science.gov (United States)

    Klimchuk, D. A.; Kordyum, E. L.; Danevich, L. A.; Tarnavskaya, E. B.; Tairbekov, M. G.; Iversen, T.-H.; Baggerud, C.; Rasmussen, O.

    Preparatory experiments for the IML-1 mission using plant protoplasts, were flown on a 14-day flight on Biokosmos 9 in September 1989. Thirty-six hours before launch of the biosatellite, protoplasts were isolated from hypocotyl cells of rapeseed (Brassica napus) and suspension cultures of carrot (Daucus carota). Ultrastructural and fluorescence analysis of cell aggregates from these protoplasts, cultured under microgravity conditions, have been performed. In the flight samples as well as in the ground controls, a portion of the total number of protoplasts regenerated cell walls. The processes of cell differentiation and proliferation under micro-g did not differ significantly from those under normal gravity conditions. However, in micro-g differences were observed in the ultrastructure of some organelles such as plastids and mitochondria. There was also an increase in the frequency of the occurrence of folds formed by the plasmalemma together with an increase in the degree of complexity of these folds. In cell cultures developed under micro-g conditions, the calcium content tends to decrease, compared to the ground control. Different aspects of using isolated protoplasts for clarifying the mechanisms of biological effects of microgravity are discussed.

  20. 20 MW Flywheel frequency regulation plant

    Energy Technology Data Exchange (ETDEWEB)

    Arseneaux, James [Beacon Power LLC, Wilmington, MA (United States)

    2015-02-05

    Hazle designed, built, commissioned, and operates a utility-scale 20 MW flywheel energy storage plant in Hazle Township, Pennsylvania (the Hazle Facility) using flywheel technology developed by its affiliate, Beacon Power, LLC (Beacon Power). The Hazle Facility provides frequency regulation services to the regional transmission organization, PJM Interconnection, LLC (PJM), through its participation in PJM’s Regulation Market (a market-based system for the purchase and sale of the Regulation ancillary service). The zero emission Hazle Facility is designed for a 20 year-life over which it is capable of performing at least 100,000 full depth of discharge cycles. To achieve its 20 MW capacity, the Hazle Facility is comprised of two hundred of Beacon Power’s 100 kilowatt (kW)/25 kilowatt/hour (kWh) flywheels connected in parallel. The Hazle Facility can fully respond to a signal from PJM in less than 2 seconds. The Hazle facility was constructed in an economic development zone designated by the Commonwealth of Pennsylvania and its construction relied on local contractors and labor for completion.

  1. Callus production and regeneration of the medicinal plant Papaver ...

    African Journals Online (AJOL)

    Administrator

    2011-09-19

    Sep 19, 2011 ... Papaver species produce a wide range of iso- quinolines ... thebaine in a green callus with relatively high levels of kinetin. .... software. RESULTS AND DISCUSSION. In this study, two different media for plant tissue culture.

  2. Plant regeneration of Lotononis bainesii Baker (Fabaceae) through ...

    African Journals Online (AJOL)

    María Laura Vidoz

    2012-05-22

    dichlorophenoxyacetic acid (2 ... source of protein in human and animal diets, balancing the amino .... All media contained MS vitamins (Sigma. M7150) and .... to the influence of plant growth regulators in the culture medium, this ...

  3. Regeneration of different plant functional types in a Masson pine forest following pine wilt disease.

    Directory of Open Access Journals (Sweden)

    Guang Hu

    Full Text Available Pine wilt disease is a severe threat to the native pine forests in East Asia. Understanding the natural regeneration of the forests disturbed by pine wilt disease is thus critical for the conservation of biodiversity in this realm. We studied the dynamics of composition and structure within different plant functional types (PFTs in Masson pine forests affected by pine wilt disease (PWD. Based on plant traits, all species were assigned to four PFTs: evergreen woody species (PFT1, deciduous woody species (PFT2, herbs (PFT3, and ferns (PFT4. We analyzed the changes in these PFTs during the initial disturbance period and during post-disturbance regeneration. The species richness, abundance and basal area, as well as life-stage structure of the PFTs changed differently after pine wilt disease. The direction of plant community regeneration depended on the differential response of the PFTs. PFT1, which has a higher tolerance to disturbances, became dominant during the post-disturbance regeneration, and a young evergreen-broad-leaved forest developed quickly after PWD. Results also indicated that the impacts of PWD were dampened by the feedbacks between PFTs and the microclimate, in which PFT4 played an important ecological role. In conclusion, we propose management at the functional type level instead of at the population level as a promising approach in ecological restoration and biodiversity conservation.

  4. Design of a Regenerable Air Revitalization Control System for the ABRS Plant Growth Facility

    Science.gov (United States)

    Monje, Oscar; Monje, Oscar; Shellack, James; Mortenson, Todd; Wells, Howard

    Design of a Regenerable Air Revitalization Control System for the ABRS Plant Growth Facility. O. Monje Space Life Sciences Laboratory, Dynamac Corp., DYN-3, Kennedy Space Center, FL 32899, USA J.L. Shellack, T.E. Mortenson, and H.W. Wells. Bionetics Corporation, BIO-1, Kennedy Space Center, FL 32899, USA The Advanced Biological Research System (ABRS) is a rear-breathing, single middeck locker equivalent plant growth system. ABRS is composed of two independently controlled growth chambers (each with 330 cm2 of growth area). The air revitalization system in each chamber is composed of two subsystems: CO2 Control and a Ethylene/VOC Control. The CO2 Control subsystem must control chamber [CO2] within a range of 300-2000 ppm, with a nominal setpoint of 1500 ppm. The Ethylene/VOC Control subsystem is required to maintain chamber ethylene concentration at ¡50 ppb. Previous spaceflight plant payloads have used non-regenerable cartridges for CO2 control and photocatalytic scrubbers for controlling concentrations of volatile organic compounds (VOCs). Non-regenerable systems have used LiOH cartridges for [CO2] control with a combination of Purafil (KMnO4)/Activated charcoal for scrubbing VOCs. Regenerable air revitalization systems offer the potential for reducing the mass and volume of consumables used during spaceflight plant experiments. A system utilizing technologies employing regenerable adsorbents: zeolites 13X and 5A for CO2 control and Carbosieve SIII (C molecular sieve) for VOC control has been designed for ABRS. The filter cartridges were sized using expected chamber leak rates, measurements of adsorptive capacities, and measured CO2 consumption and VOC generation rates.

  5. Plant Regeneration and Somatic Embryogenesis from Immature Embryos Derived through Interspecific Hybridization among Different Carica Species

    Directory of Open Access Journals (Sweden)

    Latifah Amin

    2012-12-01

    Full Text Available Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for plant regeneration and somatic embryogenesis. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora showed the highest percentage of germination, as well as plant regeneration on growth regulators free culture medium after 7 days pre-incubation on half-strength MS medium supplemented with 0.2 mg/L BAP, 0.5 mg/L NAA and 60 g/L sucrose. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora produced maximum callus, as well as somatic embryos when cultured on half-strength MS medium containing 5 mg/L 2,4-D, 100 mg/L glutamine, 100 mg/L casein hydrolysate and 60 g/L sucrose. The somatic embryos were transferred into half-strength MS medium containing 0.5 mg/L BAP and 0.2 mg/L NAA and 60 g/L sucrose for maturation. The highest number of regenerated plants per hybrid embryo (10.33 was recorded from the cross of C. papaya cv. Shahi × C. cauliflora. Isoenzyme and dendrogram cluster analysis using UPGMA of the regenerated F1 plantlets confirmed the presence of the hybrid plantlets.

  6. Plant regeneration from single-nodal-stem explants of legume tree Prosopis alba Griseb.

    Science.gov (United States)

    Castillo de Meier, G; Bovo, O A

    2000-08-01

    Seeds of Prosopis alba were scarified with abrasive paper and placed to germinate on MS (Murashige and Skoog 1962) nutrient medium. After 7 days of culture, the basal part of cotyledons was removed and pieces of 4 mm" from distal parts were cultured on Murashige and Skoog (1962) mineral salts and vitamins (MS) (3% sucrose) supplemented with growth regulators. Callus proliferation took place in the majority of the media tested. A low percentage of calluses with green buds that developed on MS basal medium containing 0.1 mg.L-1 2,4-D alone or supplemented with BAP at 0.1 mg.L-1 was observed. Neither cotyledonary segments in any medium assayed regenerated the whole plants. Bud elongation (near 70%) was achieved when single-nodal-stem segments cut from 20 days old seedlings were cultured on MS salts supplemented with 3 mg.L-1 NAA or 3 mg.L-1 IBA combined with 0.05 mg.L-1 KIN after 60 days in culture. Multiple shoots per bud were also observed. Single-nodal-stem segments from five-year-old plants were also cultured on the same media used for seedling explants. Maximal frequency of explants with bud elongation (near 70%) was found on MS with 0.1 mg.L-1 NAA plus 1 mg.L-1 BAP after 60 days of culture. Single-nodal-stem explants cut from adult trees (more than 20 years) were also employed, but the number of bud elongation was lesser. For rooting, the elongated shoots were transferred to a semisolid or liquid MS culture medium employing a paper bridge, supplemented with 0.5 mg.L-1 IBA or 0.1 mg.L-1 NAA.

  7. In vitro high frequency regeneration of plantlets of Vigna mungo and their ex vitro growth.

    Science.gov (United States)

    Agnihotri, S; Singh, R R; Chaturvedi, H C

    2001-09-01

    Of the five explants of V. mungo var. T9 used, the excised shoot tips gave best response with regard to offshoot formation followed by the embryonal axis explants. While a treatment comprising 0.5 mgL(-1) BAP, 0.5 mgL(-1) 2iP and 0.1 mgL(-1) NAA induced differentiation of an average 10 offshoots in shoot tip explants, only 3 offshoots were formed in the explants of embryonal axis in a treatment containing 0.5 mgL(-1) BAP and 0.1 mgL(-1) NAA, found optimum for them. Multiple shoots differentiated when explants with earlier regenerated and growing offshoots were first cultured in a treatment containing 0.1 mgL(-1) BAP, 0.25 mgL(-1) IAA and 5 mgL(-1) CCC and then subcultured in the same treatment but having only 1 mgL(-1) CCC. The isolated shoots rooted in 0.5 mgL(-1) IAA resulted in the formation of complete plantlets of an average height of 15 cm in 20 days. The in vitro-regenerated plants grew normally under field conditions and came to flowering as well.

  8. Plant regeneration from leaf-derived callus in Plectranthus barbatus ...

    African Journals Online (AJOL)

    RAMA

    2013-05-01

    May 1, 2013 ... Key words: Callus culture, medicinal plant, root induction, shoot organogenesis. INTRODUCTION ... media fortified with 2 mg/l 2,4-dichlorophenoxyacetic acid. The pH ... salts, vitamins, 0.5 to 2.0 mg/l BAP or Kn and in different.

  9. ANTIOXIDANT ACTIVITY IN CALLUS CULTURES AND IN VITRO REGENERATED PLANTS OF ARTEMISIA NILAGIRICA (CLARKE PAMP.- AN IMPORTANT MEDICINAL PLANT SPECIES

    Directory of Open Access Journals (Sweden)

    A. K. BALIARSINGH 1* , L. SAMANTA 2 AND S. S. MOHANTY 3

    2015-01-01

    dichlorophenoxyacetic  acid  (2,4-D  with  1.0  mg/L  Kinetin  (Kin  yielded maximum  callogenic  response.  Shoot  organogenesis  in  callus  cultures  was most favoured in MS containing 2.0 mg/L 6-benzylaminopurine (BAP and 0.5 mg/L indole-3-acetic acid (IAA. In vitro regenerated plantlets, emerged from culture medium, were acclimatized and the survival rate of ex vitro plants after soil transplantation  was 80-83% with  no apparent  phenotypic variations. The antioxidant  potential  of  natural  (in  vivo  plants,  callus  tissues  and  in  vitro regenerated plants before and after field transplantation (ex vitro plants were compared. DPPH scavenging activity was the highest in aqueous extracts of 10 week-old ex vitro plants than  other  sources.  Superoxide  anion  and  nitric  oxide  radical  scavenging  activity  was  the  highest  in ethanolic  extracts  of  10 week-old  ex  vitro  plants  where  as  the  hydroxyl  radical  was  the  maximum  in  6 week-old in vivo plants. Lipid peroxidation was neither observed in calli nor in regenerated plants of A. nilagirica.

  10. In vitro plant regeneration from leaves and internode sections of sweet cherry cultivars (Prunus avium L.).

    Science.gov (United States)

    Matt, Andrea; Jehle, Johannes A

    2005-10-01

    Regeneration of adventitious shoots from leaves and, for the first time, from internode sections were compared and optimized for five economically important sweet cherry cultivars, i.e. "Schneiders", "Sweetheart", "Starking Hardy Giant", "Kordia" and "Regina" (Prunus avium L.). The influence of basal media, carbon source, combination and dosage of phytohormones, ethylene inhibitor such as silver thiosulfate and a 16 h:8 h light:dark photoperiod versus complete darkness were evaluated. Both, DKW/WPM (1:1) and Quoirin/Lepoivre (QL) basal media stimulated organogenesis more than QL/WPM (1:1), Chee and Pool (CP), Murashige Skoog (MS), Driver and Kuniyuki (DKW) or woody plant (WPM) media did. An induction phase in darkness resulted in lower or zero regeneration rates. The best regeneration efficiencies were generally obtained with thidiazuron in combination with indole-3-butyric-acid. The addition of silver thiosulfate resulted in a similar or reduced regeneration efficiency. Significant genotypic variability in adventitious bud formation was evident for both explant sources, leaf and internode section. Adventitious shoots were obtained from 11% of leaf explants and 50% of internode sections indicating that shoot regeneration from internodes was significantly more efficient than from leaves.

  11. Exotic weeds and fluctuating microclimate can constrain native plant regeneration in urban forest restoration.

    Science.gov (United States)

    Wallace, K J; Laughlin, Daniel C; Clarkson, Bruce D

    2017-02-09

    Restoring forest structure and composition is an important component of urban land management, but we lack clear understanding of the mechanisms driving restoration success. Here we studied two indicators of restoration success in temperate rainforests: native tree regeneration and epiphyte colonization. We hypothesized that ecosystem properties such as forest canopy openness, abundance of exotic herbaceous weeds, and the microclimate directly affect the density and diversity of native tree seedlings and epiphytes. Relationships between environmental conditions and the plant community were investigated in 27 restored urban forests spanning 3 to 70 years in age and in unrestored and remnant urban forests. We used structural equation modelling to determine the direct and indirect drivers of native tree regeneration and epiphyte colonization in the restored forests. Compared to remnant forest, unrestored forest had fewer native canopy tree species, significantly more light reaching the forest floor annually, and higher exotic weed cover. Additionally, epiphyte density was lower and native tree regeneration density was marginally lower in the unrestored forests. In restored forests, light availability was reduced to levels found in remnant forests within 20 years of restoration planting, followed shortly thereafter by declines in herbaceous exotic weeds and reduced fluctuation of relative humidity and soil temperatures. Contrary to expectations, canopy openness was only an indirect driver of tree regeneration and epiphyte colonization, but it directly regulated weed cover and microclimatic fluctuations, both of which directly drove the density and richness of regeneration and epiphyte colonization. Epiphyte density and diversity were also positively related to forest basal area, as large trees provide physical habitat for colonization. These results imply that ecosystem properties change predictably after initial restoration plantings, and that reaching critical

  12. The phosphoproteome in regenerating protoplasts from Physcomitrella patens protonemata shows changes paralleling postembryonic development in higher plants.

    Science.gov (United States)

    Wang, Xiaoqin; Qi, Meiyan; Li, Jingyun; Ji, Zhongzhong; Hu, Yong; Bao, Fang; Mahalingam, Ramamurthy; He, Yikun

    2014-05-01

    The moss Physcomitrella patens is an ideal model plant to study plant developmental processes. To better understand the mechanism of protoplast regeneration, a phosphoproteome analysis was performed. Protoplasts were prepared from protonemata. By 4 d of protoplast regeneration, the first cell divisions had ensued. Through a highly selective titanium dioxide (TiO2)-based phosphopeptide enrichment method and mass spectrometric technology, more than 300 phosphoproteins were identified as protoplast regeneration responsive. Of these, 108 phosphoproteins were present on day 4 but not in fresh protoplasts or those cultured for 2 d. These proteins are catalogued here. They were involved in cell-wall metabolism, transcription, signal transduction, cell growth/division, and cell structure. These protein functions are related to cell morphogenesis, organogenesis, and development adjustment. This study presents a comprehensive analysis of phosphoproteome involved in protoplast regeneration and indicates that the mechanism of plant protoplast regeneration is similar to that of postembryonic development.

  13. Exergy analysis of internal regeneration in supercritical cycles of ORC power plant

    Science.gov (United States)

    Borsukiewicz-Gozdur, Aleksandra

    2012-09-01

    In the paper presented is an idea of organic Rankine cycle (ORC) operating with supercritical parameters and so called dry fluids. Discussed is one of the methods of improving the effectiveness of operation of supercritical cycle by application of internal regeneration of heat through the use of additional heat exchanger. The main objective of internal regenerator is to recover heat from the vapour leaving the turbine and its transfer to the liquid phase of working fluid after the circulation pump. In effect of application of the regenerative heat exchanger it is possible to obtain improved effectiveness of operation of the power plant, however, only in the case when the ORC plant is supplied from the so called sealed heat source. In the present paper presented is the discussion of heat sources and on the base of the case study of two heat sources, namely the rate of heat of thermal oil from the boiler and the rate of heat of hot air from the cooler of the clinkier from the cement production line having the same initial temperature of 260 oC, presented is the influence of the heat source on the justification of application of internal regeneration. In the paper presented are the calculations for the supercritical ORC power plant with R365mfc as a working fluid, accomplished has been exergy changes and exergy efficiency analysis with the view to select the most appropriate parameters of operation of the power plant for given parameters of the heat source.

  14. Transgenic peanut plants obtained by particle bombardment via somatic embryogenesis regeneration system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    After pre-culture and treatment of osmosis,cotyledons of immature peanut(Arachis hypogaea L.)zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene.Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin.Under continuous selection,hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons.The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR(polymerase chain reaction)for the intron-gus gene and by Southern hybridization of the hph gene.GUS enzyme activity was detected in leaflets from transgenic plants but not from control,non-transformed plants.The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.

  15. AgNO3 boosted high-frequency shoot regeneration in Vigna mungo (L.) Hepper.

    Science.gov (United States)

    Mookkan, Muruganantham; Andy, Ganapathi

    2014-01-01

    In order to further increase shoot regeneration frequency of Vigna mungo (L.) Hepper., the effects of AgNO3 on this process was investigated in this study. The shoot tip and cotyledonary node explants were cultured on MS salts B5 Vitamins medium containing BA+TDZ+Ads+AgNO3 for multiple shoot induction. AgNO3 influenced the shoot bud formation and their subsequent proliferation. The best medium composition for multiple shoot induction was BA, TDZ combination with Ads and AgNO3 in MSB5 medium. Maximum 39 shoots in cotyledonary node and 22 shoots in shoot tip were obtained per explants after 4 - 6 wk. of culture. Elongation and rooting were performed in GA3 (0.6mg/l) and IBA (0.4mg/L) containing media respectively. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to the field with a survival rate of 78%.

  16. Influence of nutrient media on callus induction, somatic embryogenesis and plant regeneration in selected Turkish crocus species.

    Science.gov (United States)

    Verma, Sandeep Kumar; Das, Ashok Kumar; Cingoz, Gunce Sahin; Uslu, Emel; Gurel, Ekrem

    2016-06-01

    Callus induction, somatic embryogenesis and plant regeneration were initiated in selected five species of Turkish crocus using three diffrent explants (leaf, stem and corm) cultured on four different media (MS, GB5, LS and CHE). The highest frequencies of callus induction (100%) and shoot regeneration (70%, with 7.2 shoots/callus) were found in the crocus species Crocus oliveri ssp. Oliveri, using the MS medium containing 5% (w/v) sucrose supplemented with (4 mg/L NAA + 4 mg/L TDZ) and (2 mg/L IAA + 2 mg/L TDZ + 2 mg/L BAP). When the embryogenic calli were transferred into the four nutrient media containing (2 mg/L IAA + 2 mg/L TDZ) and 100 mg/L ABA, these further developed into cotyledonary embryos. Maximum number of somatic embryos (2.9 embryos per leaf explant, with a frequency 46.6%) was obtained in C. oliveri ssp. Oliveri. During subculture using the half strength media, cotyledonary embryos gradually developed into plantlets.

  17. Histology, histochemistry and SEM are useful tools to study regeneration processes in plant tissue culture

    Directory of Open Access Journals (Sweden)

    Piotr Żabicki

    2013-04-01

    Full Text Available Tissue cultures in vitroare used for the multiplication of plants via direct and indirect (via callus regeneration. This approach is commonly applied in the protection of endangered species by the introduction of regenerated in vitro plantlets to botanical gardens and to the nature (so called ex situ plant conservation. In vitroconditions, especially the supplementation of tissue culture media with plant growth regulators, cause a somaclonal variation, resulting in genetic differences among regenerated plants. To analyze callus structure, including cell shapes and sizes, cell differentiation (e.g. the presence of xylem vessels and regeneration processes (organogenesis, somatic embryogenesis, the histological, histochemical and SEM techniques are applied. In this study, to obtain regeneration of plants in culture conditions, we have used three Viola species (V. epipsilaLedeb., V. stagnina Kit. and V. uliginosaBesser, indicated to be critically endangered according to Polish Red Book of Plants (Kazmierczakowa & Zarzycki 2001 and two genotypes of a model plant Arabidopsis thaliana(L. Heynh. (Columbia-0 and an insertional cdkg ;2mutant line. An Arabidopsis homozygous cdkg ;2 knock-out originated from a T 3 generation of T-DNA insertional line SALK_090262 (Alonso et al. 2003 and has been selected from a subsequent T 4 generation based on PCR analysis using primers complementary to flanking positions of full-length cDNA of CDKG;2gene product (a clone isolated by Seki et al. 2002. The aims of the study were: 1 to select the most convenient method to obtain regenerated Violaplants with maternal genotype i.e., via direct organogenesis or somatic embryogenesis; 2 to determine the effect of mutation in CDKG;2 gene on the explant response to in vitroconditions, including callus proliferation and regeneration. In three Viola species organogenesis was induced on MS (Murashige and Skoog basal medium supplied with thidiazuron (TDZ in concentrations 0.5 mg

  18. In vitro callus induction and plantlet regeneration of Achyranthes aspera L., a high value medicinal plant

    Institute of Scientific and Technical Information of China (English)

    Monokesh Kumer Sen; Shamima Nasrin; Shahedur Rahman; Abu Hena Mostofa Jamal

    2014-01-01

    Objective:To study callus induction from different explants (internode, leaf, root) and in vitro plantlets propagation from medicinally important plant Achyranthes aspera L. Methods:Sterilized explants were prepared by using 0.1%HgCl2 and 0.5%Bavistin and callus was obtained when cultured onto Murashige Skoog’s (MS) medium by using different concentrations and combination of 2,4-D, NAA, BAP, IAA, IBA with 3%sucrose and 0.8%agar. Induced callus was immediately transferred to MS medium containing at different concentrations of phytohormones for shootlets and rootlets induction respectively. Results:Sterilization treatment of 0.1%HgCl2 for 2-3 min and Bavistin 0.5%for 10-12 min showed the highest percentage of asepsis and survival rate. Maximum induction of callus was obtained from a combination of 2.0 mg/L 2,4-D and 0.5 mg/L NAA from leaf. Highest shootlets number (4.83±0.17) and length (3.8±0.16) cm were observed on full strength MS medium when fortified with BAP 4.0 mg/L and KIN 0.5 mg/L. Concerted efforts of BAP 2.0 mg/L and NAA 0.5 mg/L on full strength MS medium showed highest leaf number (6.77±0.94). In vitro raised shoots were allowed to root on different strengths of MS medium fortified with IAA and IBA at different concentrations. Experimentally, 3.0 mg/L IBA was enabled to induce maximum rootlets number (10.0±9.82) on full strength MS medium. Afterwards, regenerated shoots with well developed roots were successfully subjected to hardening process and were acclimatized. The survived plantlets showed 66.67%survival frequency without any morphological abnormality. Conclusions: The results demonstrated that different explants were good source of callus induction, morphology analysis as well as indirect plantlets regeneration.

  19. [Somatic embryogenesis and plant regeneration in vitro from young shoots of Aralia elate (Miq.) Seem].

    Science.gov (United States)

    Li, J M; Li, X W; Zhang, D Y; Xing, M

    2001-06-01

    Explants excised from the young shoots of Aralia elata (Miq.) Seem. were cultured on MS media. Calli were induced from the explants on MS medium supplemented with 0.5 mg/L 2, 4-D, 0.5 mg/L BA and 0.5 mg/L NAA. Then these calli were transferred onto the MS medium containing 2.0 mg/L 2,4-D + 0.5 mg/L BA + 0.5 mg/L NAA and 0.2% activated charcoal. Under these conditions the somatic embryoids were observed and regenerated plants were obtained from somatic embryogenesis. Then, a experimental system with stability and high regenerating efficiency has been set up for the propagation of the young plants, the cell breeding technology and the control of somatic embryogenesis of Aralia elata (Miq.).

  20. Plant Regeneration by Callus-Mediated Protocorm-Like Body Induction of Anthurium andraeanum Hort.

    Institute of Scientific and Technical Information of China (English)

    YU Yi-xun; LIU Ling; LIU Juan-xu; WANG Jing

    2009-01-01

    This research aims at developing a plant regeneration system from leaf and petiole explants of Anthurium andraeanum Hort.,thereby establish a foundation for mass production and transformation.Using tissue culture technique,the conditions for callus induction,protocorm-like body (PLB) formation and plant regeneration from leaf explants and petiole of A.andraeanum,such as basal medium and plant growth regulator,were investigated.Totipotent callus was induced on a 1/2-strength MS medium containing 0.90 μmol L-1 2,4-dichlorophenoxyacetic acid (2,4-D) and 8.88 μmol L-1 N6-benzyladenine (BA).The callus exhibited complete hormone autonomy for growth and differentiation of PLBs.This callus proliferated well and was maintained by subculturing on 1/2 MS medium containing 0.90 μmol L-1 2,4-D and 4.44 μmol L-1 BA.On average,8 protocorm-like bodies could be obtained from a piece of 4 mm callus after being transferred to the 1/2 MS medium with 4.44 μtmol L-1 BA after 8 wk of culture.The regenerated PLBs formed shoots and roots on 1/2 MS medium.After 24 wk of culture on these medium,well-developed plantlets for potting were produced.An efficient micropropagation method was established for indirect PLB formation and plant regeneration from leaf and petiole ofA.andraeanum.

  1. Regeneration of plants from mesophyll protoplasts of the wild crucifer Eruca sativa Lam.

    Science.gov (United States)

    Sikdar, S R; Chatterjee, G; Das, S; Sen, S K

    1987-12-01

    Protoplasts isolated from mesophyll cells of Eruca sativa Lam., cultured on suitable medium, underwent sustained cell divisions to form calli. The plating efficiency was found to be 0.4%. The protoplast-derived calli subsequently produced plantlets through organogenesis (15.71%) and somatic embryogenesis (11.25%). Regenerated plants exhibited normal appearance. These results indicate potential to introgress desirable traits from this wild crucifer into important oilseed and cole Brassicas by protoplast fusion and hybrid recovery.

  2. Efficient cryopreservation by droplet vitrification of pentaploid roses and the phenotype of regenerated plants

    Directory of Open Access Journals (Sweden)

    Bożena Pawłowska

    2015-12-01

    Full Text Available Shoot tips from in vitro plants of four rose species were cryopreserved by the droplet vitrification method. Optimized conditions involved exposure to loading solution for 20 min, then treatment with plant vitrification solution (PVS2 for 20 min (Rosa agrestis, R. canina and R. dumalis or 30 min (R. rubiginosa followed by freezing in liquid nitrogen. Survival rate ranged from 78.3 to 95.1%, depending on the species. Regrowth rate of shoot tips was 50.5% for R. agrestis, 63.2% for R. rubiginosa, 71.4% for R. dumalis and 78% for R. canina. The preculture of donor plants in a medium with 0.25 µM sucrose facilitated the isolation of shoot tips and increased regrowth rate after cryopreservation. Plant regeneration was carried out in Murashige and Skoog medium with 1 µM 6-benzylaminopurine, 1.5 µM gibberellic acid and 0.087 M sucrose. Plants regenerated from cryopreserved shoot tips did not display morphological alterations in comparison with non-cryopreserved shoot tip – derived plants.

  3. Floristic diversity and regeneration status of woody plants in Zengena Forest, a remnant montane forest patch in northwestern Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Desalegn Tadele; Ermias Lulekal; Destaw Damtie; Adane Assefa

    2014-01-01

    The study was conducted at Zengena forest, a fragmented remnant montane forest in northwestern Ethiopia, which surrounds Lake Zengena. The purpose was to assess the species composition, diversity and the regeneration status of woody plants. A total of 27 plots of 20 m × 20 m were sampled along the line transects laid down the altitudinal gradient from the edge of the forest encompassing the lake to the edge of the lake in eight aspects. In each plot, woody species were counted and the diameter at breast height and the height of trees and shrubs were measured. A total of 50 woody species belonging to 31 families were found, of which 17 (34%) were trees, 7 (14%) trees or shrubs, 23 (46%) shrubs and 3 (6%) lianas. The overall Shannon-Wiener diversity and evenness indices of woody species were 2.74 and 0.7, respectively. Clausena anisata had the highest relative density (23.5%), Rapanea rhododendroides the highest relative frequency (6.5%) and Prunus afri-cana the highest relative dominance (45%) and importance value index (IVI, 51.6). The total basal area and density of woody plants were 22.3 m2⋅ha-1 and 2,202 individuals⋅ha-1, respectively. The population structure showed variations among woody plants and revealed varied regeneration patterns of different species. The importance value index and population structure revealed that some species are threatened and need prioritiza-tion for conservation measures. The results suggest that remnant forest patches in the highlands of northern Ethiopia host several woody plant species that are almost disappearing in other areas due to deforestation.

  4. Dynamic of Plant Composition and Regeneration following Windthrow in a Temperate Beech Forest.

    Science.gov (United States)

    Mollaei Darabi, Sakineh; Kooch, Yahya; Hosseini, Seyed Mohsen

    2014-01-01

    The effects of soil pedoturbation (i.e., pit and mound microtopography, PM) on development of herbaceous plant species and woody species regeneration were examined in a temperate beech forest (Fagus orientalis Lipsky) in northern Iran. We recorded the vegetation in 20 pairs of disturbed and adjacent undisturbed plots and established a chronosequence of PM ages to study the effect of time since microsite formation on cover percent of herbaceous plants and woody regeneration status. According to our findings, Carex acutiformis L., Sambucus ebulus L., Brachypodium pinnatum L., and Cyclamen coum L. are found only in the PM microsites, whereas the Equisetum ramosissimum L. is recorded only under closed canopy. The coverage percent of Rubus caesius L. increased in PM microsites compared to closed canopy intensively. In addition, Albizia julibrissin Durazz. is detected in PM microsite, whereas the Acer cappadocicum B. and Prunus persica L. species were recorded only under closed canopy. We found significant differences in understory species diversity between different ages of PM, and disturbed and adjacent undisturbed plots. Our study supports that the PM complex will create a mosaic of environmental conditions. This environmental heterogeneity could be responsible for the diversity of herbaceous plant species and regeneration of woody species.

  5. Life cycle and regeneration niches of herbaceous plants in forest communities

    Directory of Open Access Journals (Sweden)

    S. A. Dubrovnaya

    2016-06-01

    Full Text Available The criterion for steady state species in the community is the possibility of a complete turnover generation. Ontogenetic structure of Fragaria vesca and Trientalis europaea cenopopulations in phytocenoses of different seral stages of forest community depended on the ecological-coenotic conditions. Cenopopulations of species with a high frequency of individuals of generative period were formed on disturbed forest communities, however, Frsagaria vesca and Trientalis europaea seedlings in disturbed forest areas were not present. For these species, regeneration niches or microbioloby were the optimal conditions for seed germination and successful completion of the initial stages of ontogenesis, dedicated to the cenopopulations of phytocenoses climax serial stages. In holistic forest communities, species showed strategy type of patients. This allowed the species to be kept on a previously developed site. Invasive-regressive ontogenetic structure of Frsagaria vesca and Trientalis europaea cenopopulations was formed in climax stages of forest communities. However, this type of ontogenetically structure of cenopopulations reflected the survival of seedlings of species in the community, but did not represent, the tenuous state of the population. The stages of the life cycle of Fragaria vesca and Trientalis europaea were confined to different cenopopulations, where they developed the necessary conditions for the flow of the hotel stages of ontogenesis. A set of populations, within which is carried out the full turnover of the generation of Frsagaria vesca and Trientalis europaea, formed a correct idea about the status of the species in the community. In terms of a mosaic of phytocenosis cenopopulation of Platanthera bifolia was presented cenopopulations loci. The development of plants within loci differed. A variety of factors in heterogeneous pine forest determined by the separation in space of the processes of formation of seeds and survival of

  6. In vitro plant regeneration system for tropical butternut squash genotypes (Cucurbita moschata

    Directory of Open Access Journals (Sweden)

    Marta Valdez-Melara

    2009-11-01

    Full Text Available An efficient and reproducible method for regeneration of commercial and pure lines of tropical butternut squash (Cucurbita moschata plants via somatic embryogenesis was developed. The influence of genotype, explant source, N6-benzylaminopurine (BAP, 2,4-dichlorophenoxyacetic acid (2,4-D and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T concentration on somatic embryogenesis induction was investigated. Friable embryogenic calli was produced from zigotic embryos (53-56% and cotyledons from seedlings (70% of C. moschata cv. Sello de Oro cultured on callus induction medium (CIM supplemented with 0.5 mg/l or 3.5 mg/l 2,4-D. No embryogenic calli was obtained from leaf segments of C. moschata cv. Sello de Oro cultured on CIM supplemented with different concentrations of BAP and 2,4-D and cotyledons from seedlings of C. moschata cv. PVG 04 cultured on CIM with BAP and 2,4,5-T. Embryogenic calli induction was achieved in 75% C. moschata pure lines evaluated and calli percentage frequency range from 5% to 34%. Successful acclimatization of squash in vitro plants was achieved in the greenhouse and in the field. Regenerated plants appeared morphologically normal and set flowers and fruits with seeds that could germinate normally. Rev. Biol. Trop. 57 (Suppl. 1: 119-127. Epub 2009 November 30.En este estudio se desarrolló un método eficiente y reproducible para la regeneración de líneas puras de la planta tropical Cucurbita moschata mediante la vía de embriogénesis somática. Además se investigó acerca de la influencia del genotipo, transplante, y la concentración de N6-benzylaminopurina (BAP, 2,4-diclorofenoxyacetico ácido (2,4-D y 2,4,5-triclorofenoxyacetico ácido (2,4,5-T en la inducción de embriogénesis somática. Los callos embriogenéticos viables fueron producidos de embriones zigóticos (53-56% y cotiledones de semillas (70% de C. moschata cv. Sello de Oro cultivados en un medio de inducción de callos (CIM suplementado con 0.5 mg/l o 3.5 mg

  7. Transformation of pecan and regeneration of transgenic plants.

    Science.gov (United States)

    McGranahan, G H; Leslie, C A; Dandekar, A M; Uratsu, S L; Yates, I E

    1993-09-01

    A gene transfer system developed for walnut (Juglans regia L.) was successfully applied to pecan (Carya illinoensis [Wang] K. Koch). Repetitively embryogenic somatic embryos derived from open-pollinated seed of 'Elliott', 'Wichita', and 'Schley' were co-cultivated with Agrobacterium strain EHA 101/pCGN 7001, which contains marker genes for beta-glucuronidase activity and resistance to kanamycin. Several modifications of the standard walnut transformation techniques were tested, including a lower concentration of kanamycin and a modified induction medium, but these treatments had no measurable effect on efficiency of transformation. Nineteen of the 764 viable inoculated embryos produced transgenic subclones; 13 of these were from the line 'Elliott'6, 3 from 'Schley'5/3, and 3 from 'Wichita'9. Transgenic embryos of 'Wichita'9 germinated most readily and three subclones were successfully micropropagated. Three transgenic plants of one of these subclones were obtained by grafting the tissue cultured shoots to seedling pecan rootstock in the greenhouse. Gene insertion, initially detected by GUS activity, was confirmed by detection of integrated T-DNA sequences using Southern analysis.

  8. EFFICIENT CALLUS INDUCTION AND PLANT REGENERATION FROM IMMATURE EMBRYO CULTURE OF TRITICUM AESTIVUM L.- THINOPYRUM INTERMEDIUM ALIEN DISOMIC ADDITION LINES

    Institute of Scientific and Technical Information of China (English)

    LI Hong-mei; LI Xing-feng; GAO Ju-rong; WANG Hong-gang

    2005-01-01

    An efficient plant regeneration system was developed from the immature embryos of Triticum aestivum L. - Thinopyrum intermedium alien disomic addition lines, which resistant to powdery mildew. The protocol was based on a series of experiments involving the callus induction and differentiation. The experiment studied the effects of embryo size on callus induction and differentiation of the immature embryos. We found that the embryo size is critical for the establishment of embryogenic callus. Immature embryos (0.8~1.5 mm) showed high ability to produce embryogenic callus capable of regenerating green plants. The medium Murashige and Skoog's (MS) added with 2mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) gave the best embryogenic callus induction, maintenance and regeneration. The embryogenic callus maintained high regeneration during six subcultures in the callus induction medium. Suitable time of partial desiccation could effectively improve the regeneration capacity of the callus cultured for 3~4 month.Bud green spot and root green spot were observed during the differentiation of callus and the difference between them was described. Regenerated shoots were rooted on half-strength MS medium containing 0.2 mg/L Naphthalene acetic acid (NAA). Plants were successfully transferred to soil and grew well. This efficient plant regeneration system provides a foundation for the study of somaclonal variation of Triticum aestivum L. - Thinopyrum intermedium alien disomic addition lines.

  9. Dynamic Frequency Response of Wind Power Plants

    DEFF Research Database (Denmark)

    Altin, Müfit

    Electricity generation from wind energy has rapidly increased for the last five years worldwide. In many countries, wind energy targets have been set in the range of 20% to 50% of all electricity generation due to the concerns of CO2 emissions, fossil fuel costs, and energy efficiency. In order...... to maintain sustainable and reliable operation of the power system for these targets, transmission system operators (TSOs) have revised the grid code requirements. Also, the TSOs are planning the future development of the power system with various wind penetration scenarios to integrate more wind power...... according to their grid codes. In these scenarios particularly with high wind power penetration cases, conventional power plants (CPPs) such as old thermal power plants are planned to be replaced with wind power plants (WPPs). Consequently, the power system stability will be affected and the control...

  10. IMPROVED PLANT REGENERATION AND IN VITRO SOMATIC EMBRYOGENESIS IN Ruta graveolens

    Directory of Open Access Journals (Sweden)

    Zuraida AR

    2014-07-01

    Full Text Available In vitro callus cultures initiated from stem segments of Ruta graveolen which later on differentiated into somatic embryoids and subsequently regenerated whole plants. Callus formation was observed in culture medium containing low concentrations of the plant growth regulators, 2,4-dichlorophenoxyacetic acid (2,4-D and/or α-naphthalene acetic acid (NAA. At 0.2 mg/L NAA was showing the highest rate (85% of callus induction. The callus appeared watery, but showed no sign of browning after a month of culture. Sub-culturing the callus on to medium with 0.2 mg/L 2,4-D showed enhanced the callus proliferation rate up to 95%. Somatic embryogenesis from callus was most successful on MS medium containing either 6 g/L agar and supplemented with 0.5 mg/L benzylaminopurine (BAP, or with 9 g/L agar, supplemented with 0.5 mg/L kinetin (KIN. The former medium was more successful in plantlet regeneration when the embryoids were subsequently transferred to regeneration medium with 3 g/L agar and 0.5 mg/L BAP.

  11. Enrichment of By-Product Materials from Steel Pickling Acid Regeneration Plants (TRP 9942)

    Energy Technology Data Exchange (ETDEWEB)

    Lu Swan, Delta Ferrites LLC

    2009-09-30

    A new process for manufacturing an enriched, iron-based product (strontium hexaferrite) in existing steel pickling acid regeneration facilities was evaluated. Process enhancements and equipment additions were made to an existing acid regeneration plant to develop and demonstrate (via pilot scale testing and partial-capacity production trials) the viability of a patented method to produce strontium-based compounds that, when mixed with steel pickling acid and roasted, would result in a strontium hexaferrite powder precursor which could then be subjected to further heat treatment in an atmosphere that promotes rapid, relatively low-temperature formation of discrete strontium hexaferrite magnetic domains yielding an enriched iron-based product, strontium hexaferrite, that can be used in manufacturing hard ferrite magnets.

  12. Development of an Efficient Plant Regeneration System for Pelargonium × Citrosum Vanleenii

    Institute of Scientific and Technical Information of China (English)

    LIAO Fang-lei; DAI Ya-juan; WANG Pan-pan; SONG Qing; LU Hong-fei

    2011-01-01

    [Objective] As a mosquito-repelling ornamental plant, Pelargonium × Citrosum Vanleenii ( P. × Citrosum Vanleenii) is hard to be acquired because of its hybrid background, the paper was to a new regeneration system of ( P. × Citrosum Vanleenii ). [Method] By studying the influence of plant growth regulators (PGRs) on e×plant type (leaves and petioles), the optimal combinations of PGRs to maximize SELSs (somatic embryo-like structure) and buds were established. [Result]0.2 mg/L NAA + 1.0 mg/L BA was best for LS (leaves segments) and 0.2mg/L NAA + 1.5 mg/L BAs was best for PS (petioles segments). Cultured plantlets were successfully acclimatized in soil where they grew nornally without any morphological variation. Although both LS and PS were usable, the leaf was a better explant for induction of embryogenic calli, somatic embryo-like structures and buds. [Conclusion]This work offered a rapid and efficient system for plant regeneration of P. × Citrosum Vanleenii.

  13. Plant regeneration of transgenic China Rose (Rosa chinensis Jacq.) from organogenic callus

    Institute of Scientific and Technical Information of China (English)

    Chen Ji-ren; Liu Rong; Chen Shou-yi; Wang Hua-fang

    2006-01-01

    Different types of explants of China Rose (Rosa chinensis Jacq.) were placed on a Schenk and Hildebrandi (SH) medium containing L-proline and 2,4-dichlorophenoxyacefic acid (2,4-D). Organogenesis was observed on callus induced from both whole leaf and petiole and the high frequency of organogenesis was observed on the whole leaf. Shoot regeneration was obtained via organogenesis. The effects of pH and concentrations of antibiotics on maintenance of organogenesis capacity were investigated in subsequent subcultures. The pH value was found to play a critical role in retaining organogenesis capacity. The binary vector pBI121,carrying the gus gene coding for β-glucuronidase (GUS) and the npt Ⅱ gene mediated by Agrobacterium tumefaciens, was used for transformation of organogenic callus using 50 mg·L-1 geneficin for selection. Six regenerated lines showed GUS activity, of which five were verified for the presence of npt Ⅱ gene by PCR.

  14. Plant regeneration of non-toxic Jatropha curcas—impacts of plant growth regulators, source and type of explants

    KAUST Repository

    Kumar, Nitish

    2011-01-28

    Jatropha curcas is an oil bearing species with multiple uses and considerable economic potential as a biofuel plant, however, oil and deoiled cake are toxic. A non-toxic variety of J. curcas is reported from Mexico. The present investigation explores the effects of different plant growth regulators (PGRs) viz. 6-benzyl aminopurine (BAP) or thidiazuron (TDZ) individually and in combination with indole-3-butyric acid (IBA), on regeneration from in vitro and field-grown mature leaf explants, in vitro and glasshouse-grown seedlings cotyledonary leaf explants of non-toxic J. curcas. In all the tested parameters maximum regeneration efficiency (81.07%) and the number of shoot buds per explants (20.17) was observed on 9.08 μM TDZ containing Murashige and Skoog’s (MS) medium from in vitro cotyledonary leaf explants. The regenerated shoot buds were transferred to MS medium containing 10 μM kinetin (Kn), 4.5 μM BAP and 5.5 μM α-naphthaleneacetic acid (NAA) for shoot proliferation. The proliferated shoots could be elongated on MS medium supplemented with 2.25 μM BAP and 8.5 μM IAA. Rooting was achieved when the basal cut end of elongated shoots were dipped in half strength MS liquid medium containing different concentrations and combinations of IBA, IAA and NAA for four days followed by transfer to growth regulators free half strength MS medium supplemented 0.25 mg/l activated charcoal. The rooted plants could be established in soil with more than 90% survival rate.

  15. Influence of nutrient composition and plant growth regulators on callus induction and plant regeneration in glutinous rice (Oryza sativa L.).

    Science.gov (United States)

    Duangsee, K; Bunnag, S

    2014-01-01

    The potential for callus induction and regeneration depends on nutrient composition and plant growth regulators. The aim of the present study was to investigate the effect of nutrient composition and plant growth regulators on callus induction and plant regeneration in the glutinous rice cultivar Khunvang. The effect of 2,4-D concentrations (1, 2, 3, 4 and 5 mg L(-1)) on callus induction and growth were investigated. The results revealed that the highest percentage of callus induction (97%) was observed in MS medium supplemented with 5 mg L(-1) 2,4-D under 16 h Photoperiod. The effects of casein hydrolysate concentrations of casein hydrolysate (0, 300, 500, 700 and 900 mg L(-1)) and proline (0, 300, 500, 700 and 900 mg L(-1)) on callus induction and growth of Khunvang were also observed. The results indicated that the increasing casein hydrolysate and proline concentrations did not show a significant effect on callus growth. However, proline concentration of 900 mg L(-1) yielded 85.67% of callus growth.

  16. Development of an efficient in vitro plant regeneration system amenable to Agrobacterium- mediated transformation of a recalcitrant grain legume blackgram (Vigna mungo L. Hepper).

    Science.gov (United States)

    Sainger, Manish; Chaudhary, Darshna; Dahiya, Savita; Jaiwal, Ranjana; Jaiwal, Pawan K

    2015-10-01

    An efficient, rapid and direct multiple shoot regeneration system amenable to Agrobacterium-mediated transformation from primary leaf with intact petiole of blackgram (Vigna mungo) is established for the first time. The effect of the explant type and its age, type and concentration of cytokinin and auxin either alone or in combination and genotype on multiple shoot regeneration efficiency and frequency was optimized. The primary leaf explants with petiole excised from 4-day-old seedlings directly developed multiple shoots (an average of 10 shoots/ explant) from the cut ends of the petiole in 95 % of the cultures on MSB (MS salts and B5 vitamins) medium containing 1.0 μM 6-benzylaminopurine. Elongated (2-3 cm) shoots were rooted on MSB medium with 2.5 μM indole-butyric acid and resulted plantlets were hardened and established in soil, where they resumed growth and reached maturity with normal seed set. The regenerated plants were morphologically similar to seed-raised plants and required 8 weeks time from initiation of culture to establish them in soil. The regeneration competent cells present at the cut ends of petiole are fully exposed and are, thus, easily accessible to Agrobacterium, making this plant regeneration protocol amenable for the production of transgenic plants. The protocol was further successfully used to develop fertile transgenic plants of blackgram using Agrobacterium tumefaciens strain EHA 105 carrying a binary vector pCAMBIA2301 that contains a neomycin phosphotransferase gene (nptII) and a β-glucuronidase (GUS) gene (uidA) interrupted with an intron. The presence and integration of transgenes in putative T0 plants were confirmed by polymerase chain reaction (PCR) and Southern blot hybridization, respectively. The transgenes were inherited in Mendelian fashion in T1 progeny and a transformation frequency of 1.3 % was obtained. This protocol can be effectively used for transferring new traits in blackgram and other legumes for their

  17. Plant regeneration by pollen embryogenesis from cultured whole spikes of barley (Hordeum vulgare).

    Science.gov (United States)

    Datta, S K

    1987-05-01

    Pollen embryogenesis and subsequent plant regeneration have been established from cultured whole barley spikes in agitated N6 liquid medium (Chu 1978) containing high levels of 2,4-D, Ficoll and potato extract. Microspore division within the anthers and subsequent embryogenic development were obtained in medium containing high amounts of reduced nitrogen with Zeatin, NAA and BAP (all at 0.5 mg/l levels, pH 6.2). Once embryoids were formed in the liquid medium, they produced secondary embryoids from the scutellum and subsequently plants on MS (Murashige and Skoog 1962) agar medium containing BAP and NAA. The ratio of green plants to albino was 1∶8.7.

  18. Survival, regeneration and leaf biomass changes in woody plants following spring burns in Burkea africana—Ochna pulchra Savanna*

    Directory of Open Access Journals (Sweden)

    M. C. Rutherford

    1981-12-01

    Full Text Available Effects of two intensities of spring burn on various aspects of woody plants of a Burkea africana—Ochna pulchra Savanna after one growth season are given. Mortality of woody plants was very low with, for example, that of individuals of Ochna pulchra being between 1 and 5%. Some species where the above-ground parts were often burned away completely, as in  Grewia flavescens, no mortality of individuals occurred. Basal regeneration shoot mass was found to depend parabolically on plant height while the ratio of leaf to twig mass in basal shoot regeneration varied inversely with plant height in  Ochna pulchra. The ability of  Ochna pulchra plants to produce new basal shoots appeared to not only depend on size of the plant but also on the number of basal shoots present prior to the fire. In live Ochna pulchra plants basal regeneration shoot biomass per individual was found to increase exponentially with greater reduction in canopy leaf biomass. This relation was also affected by possible direct heat effects. Basal shoot regeneration mass was found to vary greatly with species and varied from 0,7 g/individual for  Dichapetalum cymosum to 285,6 g/individual for Euclea natalensis. There was a clear tendency for non-suffrutex shrub species to have greater mean basal regeneration shoot mass per plant than that of most tree species. There was a compensatory effect in  Ochna pulchra between number and size of basal regeneration shoots. Standing dead woody plant individuals (before the burn were either felled by fire or apparently unaffected by fire and there was no selectivity by species. Results of the present study are generally supported by other work on the effects of fire in savanna and some other vegetation types.

  19. Control of meiotic recombination frequency in plant genomes.

    Science.gov (United States)

    Henderson, Ian R

    2012-11-01

    Sexual eukaryotes reproduce via the meiotic cell division, where ploidy is halved and homologous chromosomes undergo reciprocal genetic exchange, termed crossover (CO). CO frequency has a profound effect on patterns of genetic variation and species evolution. Relative CO rates vary extensively both within and between plant genomes. Plant genome size varies by over 1000-fold, largely due to differential expansion of repetitive sequences, and increased genome size is associated with reduced CO frequency. Gene versus repeat sequences associate with distinct chromatin modifications, and evidence from plant genomes indicates that this epigenetic information influences CO patterns. This is consistent with data from diverse eukaryotes that demonstrate the importance of chromatin structure for control of meiotic recombination. In this review I will discuss CO frequency patterns in plant genomes and recent advances in understanding recombination distributions.

  20. An efficient in vitro plant regeneration of Dipteracanthus prostratus (Poir.) Nees.- a medicinal herb

    Institute of Scientific and Technical Information of China (English)

    Jeyachandran Robert; Baskaran Xavier ravi; Cindrella Louis

    2012-01-01

    Objective: This is the first attempt for an efficient plant regeneration protocol through in vitro direct organogenesis for a valuable medicinal plant, Dipteracanthus prostratus using nodal segment. Methods: Multiple shoots were induced from nodal explants cultured on Murashige and Skoog medium supplemented with kinetin (KIN), 6-benzylaminopurine (BAP) and 1-Naphthaleneacetic acid (NAA). Results: Maximum shoot responses (80%) were obtained with kinetin at 1.0 mg-1. The rate of shoot multiplication was maintained in subsequent subculture on similar fresh culture medium. The highest shoot length (3.96cm) was obtained with seventy three percentages of shoots at 0.2 mg-1 NAA along with 1.0 mg-1 kinetin. Maximum length of root (3.63cm) was formed at 0.5 mg-1 IBA with significant responses (80%). Rooted plantlets were then transferred to perforated plastic cups and grown in the green house at 80% survival rate. Conclusions: The highest survival rate was noticed and this plant developmental protocol could be used for large- scale regeneration of D. prostratus.

  1. Plant regeneration through callus organogenesis and true-to-type conformity of plants by RAPD analysis in Desmodium gangeticum (Linn.) DC.

    Science.gov (United States)

    Cheruvathur, Meena K; Abraham, Jyothi; Thomas, T Dennis

    2013-03-01

    An efficient plant regeneration protocol was established for an endangered ethnomedicinal plant Desmodium gangeticum (Linn.) DC. Morphogenic calli were produced from 96 % of the cultures comprising the immature leaf explants on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (4.0 mg l(-1)) in combination with 6-benzylaminopurine (BA; 0.8 mg l(-1)). For callus regeneration, various concentrations of BA (1.0-5.0 mg l(-1)) or thidiazuron (TDZ; 1.0-5.0 mg l(-1)) alone or in combination with indole-3-acetic acid (IAA; 0.2-1.0 mg l(-1)) were used. Highest response of shoot regeneration was observed on MS medium fortified with TDZ (4.0 mg l(-1)) and IAA (0.5 mg l(-1)) combination. Here, 100 % cultures responded with an average number of 22.3 shoots per gram calli. Inclusion of indole-3-butyric acid in half MS medium favored rooting of recovered shoots. Out of 45 rooted plants transferred to soil, 40 survived. Total DNA was extracted from the leaves of the acclimatized plants of D. gangeticum. Analysis of random amplified polymorphic DNA using 13 arbitrary decanucleotide primers showed the genetic homogeneity in all the ten plants regenerated from callus with parental plant, suggesting that shoot regeneration from callus could be used for the true-to-type multiplication of this plant.

  2. Zinc tolerance and accumulation in stable cell suspension cultures and in vitro regenerated plants of the emerging model plant Arabidopsis halleri (Brassicaceae).

    Science.gov (United States)

    Vera-Estrella, Rosario; Miranda-Vergara, Maria Cristina; Barkla, Bronwyn J

    2009-03-01

    Arabidopsis halleri is increasingly employed as a model plant for studying heavy metal hyperaccumulation. With the aim of providing valuable tools for studies on cellular physiology and molecular biology of metal tolerance and transport, this study reports the development of successful and highly efficient methods for the in vitro regeneration of A. halleri plants and production of stable cell suspension lines. Plants were regenerated from leaf explants of A. halleri via a three-step procedure: callus induction, somatic embryogenesis and shoot development. Efficiency of callus proliferation and regeneration depended on the initial callus induction media and was optimal in the presence of 1 mg L(-1) 2,4-dichlorophenoxyacetic acid, and 0.05 mg L(-1) benzylaminopurine. Subsequent shoot and root regeneration from callus initiated under these conditions reached levels of 100% efficiency. High friability of the callus supported the development of cell suspension cultures with minimal cellular aggregates. Characterization of regenerated plants and cell cultures determined that they maintained not only the zinc tolerance and requirement of the whole plant but also the ability to accumulate zinc; with plants accumulating up to 50.0 micromoles zinc g(-1) FW, and cell suspension cultures 30.9 micromoles zinc g(-1) DW. Together this work will provide the experimental basis for furthering our knowledge of A. halleri as a model heavy metal hyperaccumulating plant.

  3. Somatic embryogenesis and regeneration of plants in the bamboo Dendrocalamus strictus.

    Science.gov (United States)

    Rao, I U; Ramanuja Rao, I V; Narang, V

    1985-08-01

    Somatic embryogenesis leading to plant regeneration has been achieved in the bamboo, Dendrocalamus strictus, by culturing seeds (caryopses) on B5 basal medium supplemented with 2,4-dichlorophenoxyacetic acid. Callus cultures obtained from the embryonal end of the seeds differentiated chlorophyllous embryoids. On transfer to a germination medium (B5 liquid, sucrose, indolebutyric acid, and ∝ -naphthaleneacetic acid) 40% of the embryoids developed into plantlets. Further development of the plantlets occured on B5 liquid medium (half strength) + sucrose (1%) + IBA (5 × 10(-7)M) + NAA (10(-7)M).

  4. First Report of Plant Regeneration via Somatic Embryogenesis from Shoot Apex-derived Callus of Hedychium muluense

    Science.gov (United States)

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of Hedychium muluense R.M. Smith, an important monocotyledonous ornamental ginger plant. Callus was induced on a modified Murashige and Skoog (MS) medium supplemented with 9.05 µM 2-4, D and 4.6µM kinetin. ...

  5. Genetic stability and phytochemical analysis of the in vitro regenerated plants of Dendrobium nobile Lindl., an endangered medicinal orchid.

    Science.gov (United States)

    Bhattacharyya, Paromik; Kumaria, Suman; Diengdoh, Reemavareen; Tandon, Pramod

    2014-12-01

    An efficient genetically stable regeneration protocol with increased phytochemical production has been established for Dendrobium nobile, a highly prized orchid for its economic and medicinal importance. Protocorm like bodies (PLBs) were induced from the pseudostem segments using thidiazuron (TDZ; 1.5 mg/l), by-passing the conventional auxin-cytokinin complement approach for plant regeneration. Although, PLB induction was observed at higher concentrations of TDZ, plantlet regeneration from those PLBs was affected adversely. The best rooting (5.41 roots/shoot) was achieved in MS medium with 1.5 mg/l TDZ and 0.25% activated charcoal. Plantlets were successfully transferred to a greenhouse with a survival rate of 84.3%, exhibiting normal development. Genetic stability of the regenerated plants was investigated using randomly amplified polymorphic DNA (RAPD) and start codon targeted (SCoT) polymorphism markers which detected 97% of genetic fidelity among the regenerants. The PIC values of RAPD and SCoT primers were recorded to be 0.92 and 0.76 and their Rp values ranged between 3.66 and 10, and 4 and 12 respectively. The amplification products of the regenerated plants showed similar banding patterns to that of the mother plant thus demonstrating the homogeneity of the micropropagated plants. A comparative phytochemical analysis among the mother and the micropropagated plants showed a higher yield of secondary metabolites. The regeneration protocol developed in this study provides a basis for ex-situ germplasm conservation and also harnesses the various secondary metabolite compounds of medicinal importance present in D. nobile.

  6. Clearcutting and Site Preparation, but Not Planting, Promoted Early Tree Regeneration in Boreal Alaska

    Directory of Open Access Journals (Sweden)

    Miho Morimoto

    2016-12-01

    Full Text Available The stand initiation stage decisively influences future forest structure and composition, particularly in the boreal forest which is a stand replacement disturbance driven system. In boreal Alaska, the conventional forest management paradigm has focused on the production of large-dimension timber, particularly white spruce (Picea glauca. However, energy generation and heating from wood is increasing, and is likely to significantly expand total forest harvest, further shifting management focus to fuelwood production. We evaluated the effects of forest harvest management practices on post-harvest regeneration by examining whether harvest type, site preparation method, and reforestation technique resulted in differences in forest regeneration in terms of species presence, dominance, basal area, and total stem biomass using a stochastic gradient boosting (TreeNet algorithm. We recorded diameter at breast height and height of white spruce, birch (Betula neoalaskana, and aspen (Populus tremuloides in 726 plots from 30 harvest units, distributed across the various harvest and treatment types, harvest years, harvest sizes, and geographical locations. Our results indicate that management practices suitable/acceptable for woody biomass production differ from the more traditional dimensional timber production from white spruce-focused management. Artificial reforestation does not differ from natural regeneration in obtaining more stems or producing greater biomass. Clearcutting and site preparation increased tree regeneration, basal area, and woody biomass when compared to a partial harvest with no site preparation. Planting of white spruce in the Alaskan boreal forest may only be necessary in some specific circumstances, such as years with no/low white spruce seed crop, or in landscapes depleted of seed trees.

  7. Visual selection and maintenance of the cell lines with high plant regeneration ability and low ploidy level in Dianthus acicularis by monitoring with flow cytometry analysis.

    Science.gov (United States)

    Shiba, Tomonori; Mii, Masahiro

    2005-12-01

    Efficient plant regeneration system from cell suspension cultures was established in D. acicularis (2n=90) by monitoring ploidy level and visual selection of the cultures. The ploidy level of the cell cultures closely related to the shoot regeneration ability. The cell lines comprising original ploidy levels (2C+4C cells corresponding to DNA contents of G1 and G2 cells of diploid plant, respectively) showed high regeneration ability, whereas those containing the cells with 8C or higher DNA C-values showed low or no regeneration ability. The highly regenerable cell lines thus selected consisted of compact cell clumps with yellowish color and relatively moderate growth, suggesting that it is possible to select visually the highly regenerable cell lines with the original ploidy level. All the regenerated plantlets from the highly regenerable cell cultures exhibited normal phenotypes and no variations in ploidy level were observed by flow cytometry (FCM) analysis.

  8. Biotechnological applications in in vitro plant regeneration studies of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

    Science.gov (United States)

    Kumar, Pankaj; Srivastava, Dinesh Kumar

    2016-04-01

    Biotechnology holds promise for genetic improvement of important vegetable crops. Broccoli (Brassica oleracea L. var. italica) is an important vegetable crop of the family Brassicaceae. However, various biotic and abiotic stresses cause enormous crop yield losses during commercial cultivation of broccoli. Establishment of a reliable, reproducible and efficient in vitro plant regeneration system with cell and tissue culture is a vital prerequisite for biotechnological application of crop improvement programme. An in vitro plant regeneration technique refers to culturing, cell division, cell multiplication, de-differentiation and differentiation of cells, protoplasts, tissues and organs on defined liquid/solid medium under aseptic and controlled environment. Recent progress in the field of plant tissue culture has made this area one of the most dynamic and promising in experimental biology. There are many published reports on in vitro plant regeneration studies in broccoli including direct organogenesis, indirect organogenesis and somatic embryogenesis. This review summarizes those plant regeneration studies in broccoli that could be helpful in drawing the attention of the researchers and scientists to work on it to produce healthy, biotic and abiotic stress resistant plant material and to carry out genetic transformation studies for the production of transgenic plants.

  9. Seedling-herbivore interactions: insights into plant defence and regeneration patterns.

    Science.gov (United States)

    Barton, Kasey E; Hanley, Mick E

    2013-08-01

    Herbivores have the power to shape plant evolutionary trajectories, influence the structure and function of vegetation, devastate entire crops, or halt the spread of invasive weeds, and as a consequence, research into plant-herbivore interactions is pivotal to our understanding of plant ecology and evolution. However, the causes and consequences of seedling herbivory have received remarkably little attention, despite the fact that plants tend to be most susceptible to herbivory during establishment, and this damage can alter community composition and structure. In this Viewpoint article we review why herbivory during early plant ontogeny is important and in so doing introduce an Annals of Botany Special Issue that draws together the latest work on the topic. In a synthesis of the existing literature and a collection of new studies, we examine several linked issues. These include the development and expression of seedling defences and patterns of selection by herbivores, and how seedling selection affects plant establishment and community structure. We then examine how disruption of the seedling-herbivore interaction might affect normal patterns of plant community establishment and discuss how an understanding of patterns of seedling herbivory can aid our attempts to restore semi-natural vegetation. We finish by outlining a number of areas where more research is required. These include a need for a deeper consideration of how endogenous and exogenous factors determine investment in seedling defence, particularly for the very youngest plants, and a better understanding of the phylogenetic and biogeographical patterns of seedling defence. There is also much still be to be done on the mechanisms of seedling selection by herbivores, particularly with respect to the possible involvement of volatile cues. These inter-related issues together inform our understanding of how seedling herbivory affects plant regeneration at a time when anthropogenic change is likely to

  10. Research Progress of Rooting on Woody Plant Regeneration Plant%木本植物再生植株生根的研究进展

    Institute of Scientific and Technical Information of China (English)

    王琼; 郭小兵; 郭玉寿

    2014-01-01

    Rooting on the plant regeneration of woody plant was the bottleneck on tissue culture construction system of plant regeneration and rapid propagation technology .Plant growth regulator , endogenous hormon , growth vigor , phenolic com-pound, polyamine, metallic element and gene transformance and so on were discussed comprehensively influence factors of rooting on regeneration plant of woody plant .Through the years of forestry experience , the main influence factors of rooting rate of plant regeneration were analyzed to provide reference for the rapid breeding of native woody plant and factory breeding .%木本植物再生植株生根是组织培养植株再生体系建设和快繁技术的瓶颈。笔者从植物生长调节剂、内源激素、植物生长势、酚类化合物、多胺、金属元素、基因转化及其它因素等8个方面综合论述了木本植物再生植株生根的影响因素,并通过多年的林业经验,总结再生植株生根率提高的主要因素,为实现木本植物再生植株生根的工厂化繁育和乡土树种快速繁育提供借鉴。

  11. Seedling–herbivore interactions: insights into plant defence and regeneration patterns

    Science.gov (United States)

    Barton, Kasey E.; Hanley, Mick E.

    2013-01-01

    Background Herbivores have the power to shape plant evolutionary trajectories, influence the structure and function of vegetation, devastate entire crops, or halt the spread of invasive weeds, and as a consequence, research into plant–herbivore interactions is pivotal to our understanding of plant ecology and evolution. However, the causes and consequences of seedling herbivory have received remarkably little attention, despite the fact that plants tend to be most susceptible to herbivory during establishment, and this damage can alter community composition and structure. Scope In this Viewpoint article we review why herbivory during early plant ontogeny is important and in so doing introduce an Annals of Botany Special Issue that draws together the latest work on the topic. In a synthesis of the existing literature and a collection of new studies, we examine several linked issues. These include the development and expression of seedling defences and patterns of selection by herbivores, and how seedling selection affects plant establishment and community structure. We then examine how disruption of the seedling–herbivore interaction might affect normal patterns of plant community establishment and discuss how an understanding of patterns of seedling herbivory can aid our attempts to restore semi-natural vegetation. We finish by outlining a number of areas where more research is required. These include a need for a deeper consideration of how endogenous and exogenous factors determine investment in seedling defence, particularly for the very youngest plants, and a better understanding of the phylogenetic and biogeographical patterns of seedling defence. There is also much still be to be done on the mechanisms of seedling selection by herbivores, particularly with respect to the possible involvement of volatile cues. These inter-related issues together inform our understanding of how seedling herbivory affects plant regeneration at a time when anthropogenic

  12. A phylogenetic survey of recombination frequency in plant RNA viruses.

    Science.gov (United States)

    Chare, E R; Holmes, E C

    2006-05-01

    The severe economic consequences of emerging plant viruses highlights the importance of studies of plant virus evolution. One question of particular relevance is the extent to which the genomes of plant viruses are shaped by recombination. To this end we conducted a phylogenetic survey of recombination frequency in a wide range of positive-sense RNA plant viruses, utilizing 975 capsid gene sequences and 157 complete genome sequences. In total, 12 of the 36 RNA virus species analyzed showed evidence for recombination, comprising 17% of the capsid gene sequence alignments and 44% of the genome sequence alignments. Given the conservative nature of our analysis, we propose that recombination is a relatively common process in some plant RNA viruses, most notably the potyviruses.

  13. Understanding Inertial and Frequency Response of Wind Power Plants: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Muljadi, E.; Gevorgian, V.; Singh, M.; Santoso, S.

    2012-07-01

    The objective of this paper is to analyze and quantify the inertia and frequency responses of wind power plants with different wind turbine technologies (particularly those of fixed speed, variable slip with rotor-resistance controls, and variable speed with vector controls).

  14. In vitro multiple shoot regeneration and plant production in Alysicarpus rugosus DC. var. heyneanus Baker.

    Science.gov (United States)

    Bhosle, S V; Thengane, R J; Thengane, S R

    2005-10-01

    A protocol for in vitro multiple shoot regeneration and plant production through seedling (shoot tip) culture was established for Alysicarpus rugosus DC. var. heyneanus Baker. Maximum number of adventitious shoots (14.4) per shoot tip explant were initiated after two subcultures on MS solid medium supplemented with IAA (2.85 microM) plus BAP (2.22 microM) after 4 weeks. Shoot elongation (3.0-3.5 cm) was achieved on MS medium without any hormones. Stunted shoots elongated on half MS medium without growth hormones. Rooting occurred in MS medium containing IAA (1.14 - 2.85 microM) alone or in combination with IBA (0.89 - 2.46 microM) and or NAA (1.07 - 2.69 microM). Maximum rooting was established in MS medium supplemented with IAA (2.85 microM). The plants were acclimatized successfully with 55% survival in pot containing cocoa peat and sand (1:1). After a month, hardened plants were transferred to pots with manure, garden soil and sand (1:2:1) for further growth and finally planted in field.

  15. Regeneration of viable oil palm plants from protoplasts by optimizing media components, growth regulators and cultivation procedures.

    Science.gov (United States)

    Masani, Mat Yunus Abdul; Noll, Gundula; Parveez, Ghulam Kadir Ahmad; Sambanthamurthi, Ravigadevi; Prüfer, Dirk

    2013-09-01

    Oil palm protoplasts are suitable as a starting material for the production of oil palm plants with new traits using approaches such as somatic hybridization, but attempts to regenerate viable plants from protoplasts have failed thus far. Here we demonstrate, for the first time, the regeneration of viable plants from protoplasts isolated from cell suspension cultures. We achieved a protoplast yield of 1.14×10(6) per gram fresh weight with a viability of 82% by incubating the callus in a digestion solution comprising 2% cellulase, 1% pectinase, 0.5% cellulase onuzuka R10, 0.1% pectolyase Y23, 3% KCl, 0.5% CaCl2 and 3.6% mannitol. The regeneration of protoplasts into viable plants required media optimization, the inclusion of plant growth regulators and the correct culture technique. Microcalli derived from protoplasts were obtained by establishing agarose bead cultures using Y3A medium supplemented with 10μM naphthalene acetic acid, 2μM 2,4-dichlorophenoxyacetic acid, 2μM indole-3-butyric acid, 2μM gibberellic acid and 2μM 2-γ-dimethylallylaminopurine. Small plantlets were regenerated from microcalli by somatic embryogenesis after successive subculturing steps in medium with limiting amounts of growth regulators supplemented with 200mg/l ascorbic acid.

  16. Morphological and physiological characteristics of rapeseed plants regenerated in vitro from thin cell layers in the presence of zinc.

    Science.gov (United States)

    Ben Ghnaya, Asma; Charles, Gilbert; Hourmant, Annick; Ben Hamida, Jeannette; Branchard, Michel

    2007-10-01

    Phytoremediation offers owners and managers of metal-contaminated sites an innovative and cost-effective option to address recalcitrant environmental contamination. The use of plants to restore or stabilize contaminated sites, known as phytoremediation, takes advantage of the natural abilities of plants to take up, accumulate or store metals. This includes the use of plants that tolerate and accumulate metals at high levels for phytoextraction and the use of plants growing under conditions that are toxic to other plants, for preventing, for example, soil erosion (phytostabilisation). Rapeseed (Brassica napus L.) was shown to be able to accumulate substantial amounts of metals combined with high biomass. Brassica napus was therefore selected for heavy metal (HM) tolerance and accumulation through in vitro selection. A selective pressure applied during the neoformation process from transversal thin cell layers (tTCLs) allowed us to select tolerant cells and tissues. Toxic metals (such as Zn) were added to the culture media in order to select zinc-tolerant plants. Exerting a selective pressure during tTCLs regeneration aimed at selecting plants with exceptional zinc tolerance and/or accumulating capacity. The morphological and physicochemical characteristics of regenerated plants cultivated in greenhouse appeared to depend very significantly on the concentration of ZnSO(4) applied during the neoformation process. Plants regenerated in the presence of ZnSO(4) at 100 microM exhibited a greater size and a higher biomass together with flowering precocity. The contents of zinc, chlorophyll, and proline were modified in the regenerated plants. Pre-treatment with an excess of ZnSO(4) (>500 microM) was responsible for a percentage of tTCLs intolerance above 96%. With lower Zn concentrations (100-250 microM), the survival rates (33-15%) were higher.

  17. In vitro plant regeneration of Albizia lebbeck (L. from seed explants

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    S. Perveen

    2013-07-01

    Full Text Available Objectives: An efficient and reproducible regeneration protocol for rapid multiplication of Albizia lebbeck (L. was developed by using intact seed explants.Methods: Murashige and Skoog's (MS medium supplemented with different hormones (BA, Kn, GA3 and TDZ was used for the induction of multiple shoots from the seed explants. Ex-vitro rooting was performed by using pulse treatment method in auxins (IBA and NAA and the complete plantlets were transferred to the field.Results: High frequency direct shoot induction was found in aseptic seed cultures of A. lebbeck on Murashige and Skoog medium supplemented with 5.0 µM TDZ (Thiadiazuron. Seeds were germinated after 7 days of culture and induced maximum 8 shoots from the region adjacent to the apex of the primary shoot of the seedling upto 25 days of incubation. Proliferating shoot cultures with increased shoot length was established by sub-culture of excised sprouting epicotyls on MS medium supplied with reduced concentrations of TDZ. Maximum shoot regeneration frequency (76 % with  highest number of shoots (21 and shoot length (5.1 cm per sprouting epicotyl was observed in the MS medium supplemented with 0.5 µM TDZ after 8 weeks of culture. Different concentrations of Indole-3-butyric acid (IBA and α-naphthalene acetic acid (NAA were tested to determine the optimal conditions for ex-vitro rooting of the microshoots. The best treatment for maximum ex-vitro root induction frequency (81 % was accomplished with IBA (250 µM pulse treatment given to the basal end of the microshoots for 30 min followed by their transfer in plastic cups containing soilrite and eventually established in normal garden soil + soilrite (1:1 with 78 % survival rate. In addition, histological study was undertaken to gain a better understanding of the regenerated shoots from the epicotyl region.Conclusion: The findings will be fruitful in getting a time saving and cost effective protocol for the in vitro propagation of Albizia

  18. Area Expansivity Moduli of Regenerating Plant Protoplast Cell Walls Exposed to Shear Flows

    Science.gov (United States)

    Fujimura, Yuu; Iino, Masaaki; Watanabe, Ugai

    2005-05-01

    To control the elasticity of the plant cell wall, protoplasts isolated from cultured Catharanthus roseus cells were regenerated in shear flows of 115 s-1 (high shear) and 19.2 s-1 (low shear, as a control). The surface area expansivity modulus and the surface breaking strength of these regenerating protoplasts were measured by a micropipette aspiration technique. Cell wall synthesis was also measured using a cell wall-specific fluorescent dye. High shear exposure for 3 h doubled both the surface area modulus and breaking strength observed under low shear, significantly decreased cell wall synthesis, and roughly quadrupled the moduli of the cell wall. Based on the cell wall synthesis data, we estimated the three-dimensional modulus of the cell wall to be 4.1± 1.2 GPa for the high shear, and 0.35± 0.2 GPa for the low shear condition, using the surface area expansivity modulus divided by the cell wall thickness, which is identical with the Young’s modulus divided by 2(1-σ), where σ is Poisson's ratio. We concluded that high shear exposure considerably strengthens the newly synthesized cell wall.

  19. A valued Indian medicinal plant – Begonia malabarica Lam. : Successful plant regeneration through various explants and field performance

    Directory of Open Access Journals (Sweden)

    Sevanan Rajeshkumar

    2009-05-01

    Full Text Available A cost-effective and efficient protocol has been described in the present work for large-scale and rapid in vitro propagation of a valuable medicinal herb Begonia malabarica Lam. (Begoniaceae by shoot auxillary-bud proliferation and organogenesis on MS medium supplemented with 6-benzylaminopurine (BA; 0.0-8.8 mg/l and indole-3-acetic acid (IAA; 0.0-2.88 mg/l at different concentrations, either alone or in combinations. Initiation of callus formation from the base of the leaf lamina was observed on MS supplemented with BA, IAA and adenine sulphate. Root induction on shoots was achieved on full strength MS with IAA/ indole-3-butyric acid (IBA at different concentrations. MS medium with 4.4 mg/l BA and 1.4 mg/l IAA elicited the maximum number of shoots (10 multiple shoots from nodal explants. Leaf-based callus differentiated into more than 28 shoots on MS with 150 mg/l adenine sulphate. The regenerated shoots were rooted on MS with 1.2 mg/l IBA within ten days. Almost 95% of the rooted shoots survived hardening when transferred to the field. The regenerated plants did not show any morphological change and variation in levels of secondary metabolites when compared with the mother stock. Thus, a reproduction of B. malabarica was established through nodal and leaf explants. This protocol can be exploited for conservation and commercial propagation of this medical plant in the Indian subcontinent and might be useful for genetic improvement programs.

  20. Establishment of Cell Suspension Culture and Plant Regeneration in Abrus precatorius L., a Rare Medicinal Plant

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    Mohammad Serajur RAHMAN

    2012-02-01

    Full Text Available A new protocol has been developed for cell culture and in vitro regeneration of Abrus precatorius that holds enormous potentiality for preparation of medicines. In vitro grown calli were cultured in Murashige and Skoog (MS liquid media in agitated condition fortified with 0.5 mg/l 6-Benzylaminopurine. Growth curve of cells revealed that the cells continued to grow until 12 days of culture and got the highest peak from day 6-8. Isolated cell was found to produce highest 8.2% calli when suspended on MS medium supplemented with 0.5 mg/l 6-Benzylaminopurine and 0.1 mg/l 1-Naphthaleneacetic acid. Callus derived from single cell produced highest number of embryo (25-28% cultured on MS medium fortified with 2.0 mg/l 6-Benzylaminopurine and 0.2 mg/l 1-Naphthaleneacetic acid. The bipolar embryos were selected and optimum shoot formation was recorded on MS medium supplemented with 2.0 mg/l 6-Benzylaminopurine and 0.1 mg/l 1-Naphthaleneacetic acid. The optimum root induction was noticed in MS medium supplemented with 1.0 mg/l 3-Indolebutyric acid. Rooted plantlets were successfully transferred to potting soil and acclimatized to outdoor conditions.

  1. Regeneration of whole plants of geranium from petioles cultured in vitro

    Directory of Open Access Journals (Sweden)

    Barbara Stefaniak

    2014-02-01

    Full Text Available Studies were made on the morphogenetic potential of petioles of Pelargonium hortorum (1 variety, 2 clones and Pelargonium peltatum (1 variety, 1 clone grown on the medium of Murashige and Skoog (MS supplemented with auxins (IAA, IBA, NAA and cytokinins (KIN, BAP, zeatin. The most intensive growth of callus of both species was observed on medium supplemented with 0.1 mg/l NAA and 10 mg/l KIN, both under constant illumination and in darkness. Differentiation of callus and regeneration of plants occurred in P. peltatum variety "PAC Dresdner Amethyst" and in P. hortorum clone 3766/4 on medium containing 1 mg/l BAP, 1 mg/l IAA and exposed to a photoperiod (L:D = 16:8.

  2. Regeneration of transgenic plants of Prunus armeniaca containing the coat protein gene of Plum Pox Virus.

    Science.gov (United States)

    da Câmara Machado, M L; da Câmara Machado, A; Hanzer, V; Weiss, H; Regner, F; Steinkellner, H; Mattanovich, D; Plail, R; Knapp, E; Kalthoff, B; Katinger, H

    1992-02-01

    A system was developed which allows the transfer of foreign genes into apricot cultivars. We report the transformation and regeneration of Prunus armeniaca plants with Agrobacterium tumefaciens strain LBA 4404 containing various binary plasmids, pBinGUSint, carrying the marker gene ß-glucuronidase (GUS) and pBinPPVm, carrying the coat protein gene of Plum Pox Virus (PPV). The marker gene GUS was used for optical evaluation of the efficiency of the transformation system. The coat protein gene of PPV was used to introduce coat protein mediated resistance against one of the most important pathogens of stone fruit trees in Europe and the whole Mediterranean area. This is the first report of the successful integration of a viral coat protein gene into a fruit tree species, opening a new perspective on the control of the disease.

  3. Somatic Embryogenesis and Plant Regeneration from Cultured Immature Embryos of Rye (Secale cereale L.).

    Science.gov (United States)

    Lu, C Y; Chandler, S F; Vasil, I K

    1984-07-01

    Somatic embryogenesis was initiated in immature embryos of rye (Secale cereale L.) cultured on Murashige and Skoog's (1962) medium supplemented with various concentrations of 2,4-D and sucrose. The developmental stage of the embryo (optimal embryo length 0.5-2.0 mm) and concentration of 2,4-D (optimal concentration 2.5 mg · l(-1)) were found to be critical in determining embryo response. The phenoxyacetic acids, 2,4-D, 2,4,5-T, and MCPA were more effective in initiating embryogenic callus and embryoid formation than other auxins (NAA, IBA, IAA, IPA). Embryogenic callus and embryoid production was greater in embryos cultured scutellum up, and more embryoids were formed in the dark than in the light. Embryoids germinated after transfer to basal medium with/without cytokinin or GA3. The regenerated plants were grown to maturity in soil and were shown to have the normal diploid chromosome number of 14.

  4. EFFECTS OF RESTRICTED BASILAR PAPILLAR LESIONS AND HAIR CELL REGENERATION ON AUDITORY FOREBRAIN FREQUENCY ORGANIZATION IN ADULT EUROPEAN STARLINGS

    Science.gov (United States)

    Irvine, Dexter R. F.; Brown, Mel; Kamke, Marc R.; Rubel, Edwin W

    2009-01-01

    The frequency organization of neurons in the forebrain Field L complex (FLC) of adult starlings was investigated to determine the effects of hair cell (HC) destruction in the basal portion of the basilar papilla (BP) and of subsequent HC regeneration. Conventional microelectrode mapping techniques were used in normal starlings and in lesioned starlings either 2 days or 6–10 weeks after aminoglycoside treatment. Histological examination of the BP and recordings of auditory brainstem evoked responses confirmed massive loss of HCs in the basal portion of the BP and hearing losses at frequencies above 2 kHz in starlings tested 2 days after aminoglycoside treatment. In these birds, all neurons in the region of the FLC in which CFs normally increase from 2 to 6 kHz had characteristic frequency (CF) in the range 2–4 kHz. The significantly elevated thresholds of responses in this region of altered tonotopic organization indicated that they were the residue of pre-lesion responses and did not reflect central nervous system plasticity. In the long-term recovery birds, there was histological evidence of substantial HC regeneration. The tonotopic organization of the high frequency region of the FLC did not differ from that in normal starlings, but the mean threshold at CF in this frequency range was intermediate between the values in the normal and lesioned short-recovery groups. The recovery of normal tonotopicity indicates considerable stability of the topography of neuronal connections in the avian auditory system, but the residual loss of sensitivity suggests deficiencies in high-frequency HC function. PMID:19474314

  5. Effects of restricted basilar papillar lesions and hair cell regeneration on auditory forebrain frequency organization in adult European starlings.

    Science.gov (United States)

    Irvine, Dexter R F; Brown, Mel; Kamke, Marc R; Rubel, Edwin W

    2009-05-27

    The frequency organization of neurons in the forebrain Field L complex (FLC) of adult starlings was investigated to determine the effects of hair cell (HC) destruction in the basal portion of the basilar papilla (BP) and of subsequent HC regeneration. Conventional microelectrode mapping techniques were used in normal starlings and in lesioned starlings either 2 d or 6-10 weeks after aminoglycoside treatment. Histological examination of the BP and recordings of auditory brainstem evoked responses confirmed massive loss of HCs in the basal portion of the BP and hearing losses at frequencies >2 kHz in starlings tested 2 d after aminoglycoside treatment. In these birds, all neurons in the region of the FLC in which characteristic frequencies (CFs) normally increase from 2 to 6 kHz had CF in the range of 2-4 kHz. The significantly elevated thresholds of responses in this region of altered tonotopic organization indicated that they were the residue of prelesion responses and did not reflect CNS plasticity. In the long-term recovery birds, there was histological evidence of substantial HC regeneration. The tonotopic organization of the high-frequency region of the FLC did not differ from that in normal starlings, but the mean threshold at CF in this frequency range was intermediate between the values in the normal and lesioned short-recovery groups. The recovery of normal tonotopicity indicates considerable stability of the topography of neuronal connections in the avian auditory system, but the residual loss of sensitivity suggests deficiencies in high-frequency HC function.

  6. Potassium chloride and rare earth elements improve plant growth and increase the frequency of the Agrobacterium tumefaciens-mediated plant transformation.

    Science.gov (United States)

    Boyko, Alex; Matsuoka, Aki; Kovalchuk, Igor

    2011-04-01

    Plant transformation efficiency depends on the ability of the transgene to successfully interact with plant host factors. Our previous work and the work of others showed that manipulation of the activity of host factors allows for increased frequency of transformation. Recently we reported that exposure of tobacco plants to increased concentrations of ammonium nitrate increases the frequency of both homologous recombination and plant transgenesis. Here we tested the influence of KCl and salts of rare earth elements, Ce and La on the efficiency of Agrobacterium-mediated plant transformation. We found that exposure to KCl, CeCl(3) and LaCl(3) leads to an increase in recombination frequency in Arabidopsis and tobacco. Plants grown in the presence of CeCl(3) and LaCl(3) had higher biomass, longer roots and greater root number. Analysis of transformation efficiency showed that exposure of tobacco plants to 50 mM KCl resulted in ~6.0-fold increase in the number of regenerated calli and transgenic plants as compared to control plants. Exposure to various concentrations of CeCl(3) showed a maximum increase of ~3.0-fold in both the number of calli and transgenic plants. Segregation analysis showed that exposure to KCl and cerium (III) chloride leads to more frequent integrations of the transgene at a single locus. Analysis of transgene intactness showed better preservation of right T-DNA border during transgene integration. Our data suggest that KCl and CeCl(3) can be effectively used to improve quantity and quality of transgene integrations.

  7. Optimization of a Virtual Power Plant to Provide Frequency Support.

    Energy Technology Data Exchange (ETDEWEB)

    Neely, Jason C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Johnson, Jay [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gonzalez, Sigifredo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lave, Matthew Samuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Delhotal, Jarod James [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    Increasing the penetration of distributed renewable sources, including photovoltaic (PV) sources, poses technical challenges for grid management. The grid has been optimized over decades to rely upon large centralized power plants with well-established feedback controls, but now non-dispatchable, renewable sources are displacing these controllable generators. This one-year study was funded by the Department of Energy (DOE) SunShot program and is intended to better utilize those variable resources by providing electric utilities with the tools to implement frequency regulation and primary frequency reserves using aggregated renewable resources, known as a virtual power plant. The goal is to eventually enable the integration of 100s of Gigawatts into US power systems.

  8. Direct regeneration of Periwinkle (Catharanthus roseus via node explants culture and different combinations of plant growth regulators

    Directory of Open Access Journals (Sweden)

    M. Talebi

    2012-09-01

    Full Text Available Periwinkle (Catharanthus roseus L., Apocynaceae contains more than 130 different terpenoid indole alkaloids (TIAs, of which two dimeric alkaloids, Vinblastine and Vincristine, have antineoplastic activity and are useful in treatment of various cancers. Specific production of some alkaloids in differentiated tissues such as leaf and stem led to use direct regeneration of explants in order to increase the production of these important alkaloids in the plant. In this research, 30 combinations of plant growth regulators and activated charcoal were used in MS media for direct regeneration of node explants. Application of BAP in media containing 1 g/l activated charcoal showed the best direct regeneration of node explants and shoot proliferation. Although application of activated charcoal is necessary for periwinkle growth in media due to many phenolic compounds, but it has negative effects on adsorption of plant growth regulators and consequently reduce shoot proliferation. Therefore, it seems that 1 g/l activated charcoal is an appropriate concentration for preparing shoot proliferation media. In addition, transporting regenerated shoots to culture media containing NAA resulted in increasing shoot length. Proliferated shoots rooted in media without PGR and with 2 g/l activated charcoal and acclimated with environmental conditions after transferring to the soil.

  9. Doubled haploid production from Spanish onion (Allium cepa L. germplasm: embryogenesis induction, plant regeneration and chromosome doubling

    Directory of Open Access Journals (Sweden)

    Oreto eFayos

    2015-05-01

    Full Text Available The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09% and Fuentes de Ebro the lowest (0.53%. These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%, whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%. Different amiprofos-methyl (APM treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 µM APM in liquid medium. However, the application of 25 µM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their

  10. Callus induction and plant regeneration in the moss Aloina Aloides (Schultz Kindb. (Pottiaceae, Bryopsida

    Directory of Open Access Journals (Sweden)

    Bijelović Aneta

    2003-01-01

    Full Text Available Callus induction of moss species Aloina aloides (Schultz Kindb. was obtained on Murashige and Skoog (MS medium supplemented with 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D or with 1.0 mg/L 2,4-D and 1.0 mg/L kinetin (KIN or with 0.2 mg/L indole-3-butyric acid (IBA and 2.0 mg/L 6-benzylaminopurine (BAP or with 7.5 g/L of sucrose or with 15 g/L of sucrose or hormone - free and sugar free MS basal medium. The callus can be maintained for a long period of time without bud formation subcultured on the above media, at 16 h day/8 h night, 25 ± 2ºC, 60-70% air humidity and irradiance of 50 μmol m-2s-1. To obtain plant regeneration pieces, calli were transferred onto MS media supplemented with different concentrations of auxins and cytokinins (1.0 mg/L 2,4-D and 2 mg/L KIN; 0.2 mg/L IBA and 2 mg/L KIN; or 0.2 mg/L IAA and 2 mg/L BAP. In these media after subculturing, callus enlarges and turns to gametophytes with buds. Except for a smaller size, the plants obtained on the callus did not differ morphoanatomically from the shoots in the nature.

  11. The Role of Nitrobenzoic Acid Derivatives on Callus Induction and Plant Regeneration in Paulownia shan tong

    Directory of Open Access Journals (Sweden)

    Roxana Luca

    2016-11-01

    Full Text Available Paulownia is a multipurpose tree species with a rapid growth which is cultivated in several temperate zones worldwide for its economic importance. The present study was undertaken to investigate the effects of different alkanolamine salts of 4-nitrobenzoic acid on in vitro callus induction and plant regenerating in Paulownia shan tong.The alkanolamine salts, namely methylethanolamine 4-nitrobenzoate (4-NO2BA MMEA, diethanolamine 4-nitrobenzoate (4-NO2BA DEA and triethanolamine 4-nitrobenzoate (4-NO2BA TEA are new synthesized compounds with biological activity and low toxicity. The influence of title compounds on sprout length, number of internodes, number of leaves and number of ramifications has been studied at two different concentrations: 1 mg/L respectively 0.5 mg/L. The experimental data show that new tested compounds have a better growth effect on plant vegetable parties in report to control, the most eloquent results being obtained for 4-NO2BA MMEA. For callus induction 2,4-D hormonal balances were attempted and the development of callus was examined at two different concentrations. An induced callus development was observed regarding callus dimensions for all explants inoculated on culture medium supplemented with 2,4-D.

  12. Hyperaccumulation of nickel by hairy roots of alyssum species: comparison with whole regenerated plants.

    Science.gov (United States)

    Nedelkoska, T V; Doran, P M

    2001-01-01

    Hairy roots were used to investigate nickel uptake by the hyperaccumulator species, Alyssum bertolonii, A. tenium, and A. troodii. The Ni biosorption capacity of A. tenium hairy roots was lower than for other types of biomass such as bacteria and algae; in short-term (9-h) equilibrium studies, the highest Ni content measured in the roots was 17 500 microg g(-1) dry weight at a liquid concentration of about 4000 ppm. Using long-term hairy root cultures, it was demonstrated that Ni tolerance and hyperaccumulation do not necessarily depend on the presence of shoots or root-shoot translocation. A. bertolonii hairy roots remained healthy in appearance and continued to grow in the presence of 20-100 ppm Ni, accumulating up to 7200 microg g(-1) dry weight Ni. In contrast, hairy roots of Nicotiana tabacum turned dark brown at 20 ppm Ni and growth was negligible. The ability to grow at high external Ni concentrations allowed hyperaccumulator hairy roots to remove much greater amounts of heavy metals from the culture liquid than nonhyperaccumulator hairy roots, even though biomass Ni concentrations were similar. Although hairy roots proved to be a useful tool for investigating Ni hyperaccumulation, there were significant differences in the Ni uptake capacity of hairy roots and whole plants. Regenerated plants of A. tenium were much more tolerant of Ni and capable of accumulating higher Ni concentrations than hairy roots of this species.

  13. Agrobacterium-Mediated Transformation of Embryogenic Calli of Anliucheng and Regeneration of Plants Containing the Chimaeric Ribonuclease Gene

    Institute of Scientific and Technical Information of China (English)

    LI Dong-dong; SHI Wei; DENG Xiu-xin

    2003-01-01

    Anliucheng (Citrus sinensis Osbeck), a very seedy and widely spread acidless sweet orange cultivar in south of China, was transformed by the strain of Agrobacterium Tumefaciens EHA105 carrying pTA29-barnase gene, which will induce pollen sterility in transgenic plants. The embryogenic calli of Anliucheng were co-cultivated with Agrobacterium tumefaciens for 3 days, and then transferred to selective medium containing 50 mg L-1 basta (a kind of herbicide) for 5 weeks. The resistant calli were recovered and regenerated 118 embryoids. A total of 13 entire plants were obtained after micro-grafted on trifoliate orange. These regenerated plants were verified by PCR amplification and confirmed by PCR-Southern blotting analysis.

  14. A novel combination of plant growth regulators for in vitro regeneration of complete plantlets of guar [Cyamopsis tetragonoloba (L.) Taub].

    Science.gov (United States)

    Verma, S; Gill, K S; Pruthi, V; Dhugga, K S; Randhaw, G S

    2013-12-01

    A novel combination of plant growth regulators comprising indole-3-butyric acid (IBA), 6-benzylaminopurine (BA) and gibberellic acid (GA3) in Murashige and Skoog basal medium has been formulated for in vitro induction of both shoot and root in one culture using cotyledonary node explants of guar, (Cyamopsis tetragonoloba). Highest percentages of shoot (92%) and root (80%) induction were obtained in the medium containing (mg/L) 2 IBA, 3 BA and 1 GA3. Shoot regeneration from the cotyledonary node explants was observed after 10-15 days. Regeneration of roots from these shoots occurred after 20 to 25 days. The regenerated plantlets showed successful acclimatization on transfer to soil. This protocol is expected to be helpful in carrying out various in vitro manipulations in this economically and industrially important legume.

  15. In vitro plant regeneration of two cucumber (Cucumis sativum L. genotypes: Effects of explant types and culture medium

    Directory of Open Access Journals (Sweden)

    Grozeva Stanislava

    2014-01-01

    Full Text Available The effect of different phytohormone concentrations on callusogenesis and organogenesis in two cucumber genotypes were studied. It was established that the rate of plant regeneration depends on genotype, explant type and culture medium. Hypocotyls were found to be more responsive than cotyledons in morphogenesis. In vitro planlet-regenerants have been obtained in hypocotyls explants on culture medium with 1.0 and 2.0 mgL-1 BA for cultivar Gergana and in 1.0 and 3.0 mgL-1K-line 15B. Induction of regeneration in cotyledons were established only in cultivar Gergana on culture medium supplemented with 3.0 mgL-1 BA and in combination of 0.5 mgL-1IAA.

  16. Establishment of High-frequency in Vitro Regeneration System of Onion%洋葱高频离体再生体系的建立

    Institute of Scientific and Technical Information of China (English)

    王建军; 刘照坤; 侯喜林; 杨学东; 孔敏; 李满堂

    2012-01-01

    以洋葱(Allium cepa L.)品种‘W465’的幼嫩花序和不同发育时期的幼蕾为外植体材料,研究激素配比对其愈伤组织诱导、再生和生根驯化的影响,以建立洋葱高频离体再生体系。研究结果表明,洋葱幼嫩花序为最佳外植体材料,在含有1.0mg.L^-12,4-D+1.0mg.L^-16-BA的B5培养基上愈伤诱导率为100%,在添加1.0mg.L^-1TDZ的B5培养基上再生芽分化率为78.13%,在1/2MS+0.01mg.L^-1NAA培养基上可诱导生根,驯化移栽成活率达到95%。%With the young umbels and buds of onion (Allium cepa L.) at different development stage, a high frequency regeneration system of onion in vitro was established by analysis the effects of explant type and plant growth regulator combination on callus' induction, shoot regeneration and rooting. The optimum condition was showed as with young umbels on B5 medium with 1.0 mg. L^-1 2,4-D + 1.0mg. L^-1 6-BA, with the callus induction rate reaching 100%. The optimum hormone concentration of getting high-frequency regeneracy shoot, with 78.13%, from callus was 1.0 mg·L^-1 thidiazuron (TDZ) on B5 medium. All shoots rooted on 1/2MS medium with 0.01 mg · L^-1 NAA, the regenerated plantlet were domesticated and transplanted in greenhouse: The survival rate was 95%.

  17. Plant regeneration from cotyledonary explants of Eucalyptus camaldulensis dehn and histological study of organogenesis in vitro

    Directory of Open Access Journals (Sweden)

    Roberson Dibax

    2010-04-01

    Full Text Available The present work aimed at regenerating plants of Eucalyptus camaldulensis from the cotyledonary explants and describing the anatomy of the tissues during callogenesis and organogenesis processes, in order to determine the origin of the buds. The cotyledonary leaves of E. camaldulensis were cultured in Murashige and Skoog (MS, WPM and JADS media supplemented with 2.7 µM NAA and 4.44 µM BAP. The best results for bud regeneration were obtained on MS and WPM media (57.5 and 55% of calluses formed buds, respectively. Shoot elongation and rooting (80% were obtained on MS/2 medium (with half-strength salt concentration with 0.2% activated charcoal. Acclimatization was performed in the growth chamber for 48 h and then the plants were transferred to a soil:vermiculite mixture and cultured in a greenhouse. Histological studies revealed that the callogenesis initiated in palisade parenchyma cells and that the adventitious buds were formed from the calluses, indicating indirect organogenesis.Este trabalho teve como objetivo a obtenção de plantas de Eucalyptus camaldulensis a partir de folhas cotiledonares e o estudo da anatomia dos tecidos durante a calogênese e organogênese para determinar a origem das gemas. Folhas cotiledonares foram cultivadas em meios de cultura MS, WPM e JADS suplementados com 2,7 µM de ANA e 4,44 µM de BAP. Os melhores resultados para a regeneração de gemas foram obtidos com os meios MS e WPM. Para o alongamento e enraizamento, o meio de cultura MS/2 contendo 0,2% de carvão ativado apresentou-se eficiente para ambas as etapas. A aclimatização foi realizada mediante a abertura dos frascos na sala de crescimento por 48 horas, seguido da transferência para casa-de-vegetação com nebulização intermitente. Estudos histológicos foram conduzidos e revelaram que a calogênese teve início nas células do parênquima paliçádico e que as gemas adventícias formaram-se a partir dos calos, indicando a organogênese indireta.

  18. Fatigue failure of regenerator screens in a high frequency Stirling engine

    Science.gov (United States)

    Hull, David R.; Alger, Donald L.; Moore, Thomas J.; Scheuermann, Coulson M.

    1988-01-01

    Failure of Stirling Space Power Demonstrator Engine (SPDE) regenerator screens was investigated. After several hours of operation the SPDE was shut down for inspection and on removing the regenator screens, debris of unknown origin was discovered along with considerable cracking of the screens in localized areas. Metallurgical analysis of the debris determined it to be cracked-off-deformed pieces of the 41 micron thickness Type 304 stainless steel wire screen. Scanning electron microscopy of the cracked screens revealed failures occurring at wire crossovers and fatigue striations on the fracture surface of the wires. Thus, the screen failure can be characterized as a fatigue failure of the wires. The crossovers were determined to contain 30 percent reduction in wire thickness and a highly worked microstructure occurring from the manufacturing process of the wire screens. Later it was found that reduction in wire thickness occurred because the screen fabricator had subjected it to a light cold-roll process after weaving. Installation of this screen left a clearance in the regenerator allowing the screens to move. The combined effects of the reduction in wire thickness, stress concentration (caused by screen movement), and highly worked microstructure at the wire crossovers led to the fatigue failure of the screens.

  19. Embryogenesis induction, callogenesis, and plant regeneration by in vitro culture of tomato isolated microspores and whole anthers.

    Science.gov (United States)

    Seguí-Simarro, José M; Nuez, Fernando

    2007-01-01

    In this work, some of the different in vitro developmental pathways into which tomato microspores or microsporocytes can be deviated experimentally were explored. The two principal ones are direct embryogenesis from isolated microspores and callus formation from meiocyte-containing anthers. By means of light and electron microscopy, the process of early embryogenesis from isolated microspores and the disruption of normal meiotic development and change of developmental fate towards callus proliferation, morphogenesis, and plant regeneration have been shown. From microspores isolated at the vacuolate stage, embryos can be directly induced, thus avoiding non-androgenic products. In contrast, several different morphogenic events can be triggered in cultures of microsporocyte-containing anthers under adequate conditions, including indirect embryogenesis, adventitious organogenesis, and plant regeneration. Both callus and regenerated plants may be haploid, diploid, and mostly mixoploid. The results demonstrate that both gametophytic and sporophytic calli occur in cultured tomato anthers, and point to an in vitro-induced disturbance of cytokinesis and subsequent fusion of daughter nuclei as a putative cause for mixoploidy and genome doubling during both tetrad compartmentalization and callus proliferation. The potential implications of the different alternative pathways are discussed in the context of their application to the production of doubled-haploid plants in tomato, which is still very poorly developed.

  20. [Induction and in vitro culture of hairy roots of Dianthus caryophyllus and its plant regeneration].

    Science.gov (United States)

    Shi, Heping; Zhu, Yuanfeng; Wang, Bei; Sun, Jiangbing; Huang, Shengqin

    2014-11-01

    To use Agrobacterium rhizogenes-induced hairy roots to create new germplasm of Dianthus caryophyllus, we transformed D. caryophyllus with A. rhizogenes by leaf disc for plant regeneration from hairy roots. The white hairy roots could be induced from the basal surface of leaf explants of D. caryophyllus 12 days after inoculation with A. rhizogenes ATCC15834. The percentage of the rooting leaf explants was about 90% 21 days after inoculation. The hairy roots could grow rapidly and autonomously in liquid or solid phytohormone-free MS medium. The transformation was confirmed by PCR amplification of rol gene of Ri plasmid and silica gel thin-layer chromatography of opines from D. caryophyllus hairy roots. Hairy roots could form light green callus after cultured on MS+6-BA 1.0-3.0 mg/L + NAA 0.1-0.2 mg/L for 15 days. The optimum medium for adventitious shoots formation was MS + 6-BA 2.0 mg/L + NAA 0.02 mg/L, where the rate of adventitious shoot induction was 100% after cultured for 6 weeks. The mean number of adventitious shoot per callus was 30-40. The adventitious shoots can form roots when cultured on phytohormone-free 1/2 MS or 1/2 MS +0.5 mg/L NAA for 10 days. When the rooted plantlets transplanted in the substrate mixed with perlite sand and peat (volume ratio of 1:2), the survival rate was above 95%.

  1. Novel sporophyte-like plants are regenerated from protoplasts fused between sporophytic and gametophytic protoplasts of Bryopsis plumosa.

    Science.gov (United States)

    Yamagishi, Takahiro; Hishinuma, Tasuku; Kataoka, Hironao

    2004-06-01

    Protoplasts of the marine coenocytic macrophyte Bryopsis plumosa (Hudson) C. Agardh. [Caulerpales] can easily be obtained by cutting gametophytes or sporophytes with sharp scissors. When a protoplast isolated from a gametophyte was fused with a protoplast isolated from a sporophyte of this alga, it germinated and developed into either one of two completely different forms. One plant form, named Type G, appeared quite similar to a gametophyte, and the other, named Type S, looked similar to a sporophyte. While the Type G plant contained many small nuclei of gametophyte origin together with a single giant nucleus of sporophyte origin, the Type S plant contained many large nuclei of uniform size. These large nuclei in the Type S plant had metamorphosed from the gametophytic nuclei, and were not formed through division of the giant nucleus of sporophyte origin. Fragments of the Type S plant, each having such a large nucleus, developed into creeping filaments that look very similar to sporophytes. While cell walls of gametophytes and Type G plants were stained by Congo-red, those of the thalli of regenerated Type S plants and sporophytes were not stained by the dye. This indicated that the large nuclei of the Type S plant did not express genes for xylan synthesis, which are characteristic of gametophytes. Two-dimensional gel electrophoretic analysis revealed that most of the proteins synthesized in the Type S plant were identical to those of sporophytes. These results strongly suggest that in the Type S plant, the gametophytic nuclei are transformed into sporophyte-like nuclei by an unknown factor(s) produced by the giant nucleus of sporophyte origin and that the transformed nuclei express the set of genes characteristic of sporophytes. Despite morphological similarity, however, the regenerated Type S plant could not produce zoospores, because its large nuclei did not divide normally. The transformed large nuclei of gametophyte origin still seemed to be in the haploid

  2. Efficient callus formation and plant regeneration of goosegrass [Eleusine indica (L.) Gaertn.].

    Science.gov (United States)

    Yemets, A I; Klimkina, L A; Tarassenko, L V; Blume, Y B

    2003-02-01

    Efficient methods in totipotent callus formation, cell suspension culture establishment and whole-plant regeneration have been developed for the goosegrass [ Eleusine indica (L.) Gaertn.] and its dinitroaniline-resistant biotypes. The optimum medium for inducing morphogenic calli consisted of N6 basal salts and B5 vitamins supplemented with 1-2 mg l(-1) 2,4-dichlorophenoxyacetic acid (2,4-D), 2 mg l(-1) glycine, 100 mg l(-1) asparagine, 100 mg l(-1) casein hydrolysate, 30 g l(-1) sucrose and 0.6% agar, pH 5.7. The presence of organogenic and embryogenic structures in these calli was histologically documented. Cell suspension cultures derived from young calli were established in a liquid medium with the same composition. Morphogenic structures of direct shoots and somatic embryos were grown into rooted plantlets on medium containing MS basal salts, B5 vitamins, 1 mg l(-1) kinetin (Kn) and 0.1 mg l(-1) indole-3-acetic acid (IAA), 3% sucrose, 0.6% agar, pH 5.7. Calli derived from the R-biotype of E. indica possessed a high resistance to trifluralin (dinitroaniline herbicide) and cross-resistance to a structurally non-related herbicide, amiprophosmethyl (phosphorothioamidate herbicide), as did the original resistant plants. Embryogenic cell suspension culture was a better source of E. indica protoplasts than callus or mesophyll tissue. The enzyme solution containing 1.5% cellulase Onozuka R-10, 0.5% driselase, 1% pectolyase Y-23, 0.5% hemicellulase and N(6) mineral salts with an additional 0.2 M KCl and 0.1 M CaCl(2) (pH 5.4-5.5) was used for protoplast isolation. The purified protoplasts were cultivated in KM8p liquid medium supplemented with 2 mg l(-1) 2,4-D and 0.2 mg l(-1) Kn.

  3. Effect of polyamines and silver nitrate on the high frequency regeneration from cotyledon explants of bottle gourd (Lagenaria siceraria; sp. asiatica).

    Science.gov (United States)

    Shyamali, Saha; Hattori, Kazumi

    2007-04-15

    In this study, we have investigated the effect ofpolyamines (PA) and silver nitrate (AgNO3) on the high frequency regeneration from cotyledon explants of bottle gourd containing Murashige and Skoog (MS) media supplemented with different kind of Cytokinin alone or in the combination. Synergistic effect of kinetin (1 mg L(-1)) and benzyl adenine (BA) (2 mg L(-1)) itself showed highest shoot regeneration (80.6%) efficiency than BA or Kinetin alone in cotyledon explants of bottle gourd without adding AgNO3 or PAs. We have also observed that PAs and AgNO3 show their sensitivity on the regeneration, which is hormonal dependent. Regenerated shoots were rooted in half strength MS media containing 0.1 mg L(-1) IAA.

  4. Factors affecting in vitro plant regeneration of the critically endangered Mediterranean knapweed ( Centaurea tchihatcheffii Fisch et. Mey)

    Science.gov (United States)

    Ozel, Cigdem Alev; Khawar, Khalid Mahmood; Mirici, Semra; Ozcan, Sebahattin; Arslan, Orhan

    2006-10-01

    Habitat destruction has resulted in the extinction of many plant species from the earth, and many more face extinction. Likely, the annual endemic Mediterranean knapweed ( Centaurea tchihatcheffii) growing in the Golbasi district of Ankara, Turkey is facing extinction and needs urgent conservation. Plant tissue culture, a potentially useful technique for ex situ multiplication, was used for the restoration of this ill-fated plant through seed germination, micropropagation from stem nodes, and adventitious shoot regeneration from immature zygotic embryos. The seeds were highly dormant and very difficult to germinate. No results were obtained from the micropropagation of stem nodes. However, immature zygotic embryos showed the highest adventitious shoot regeneration on Murashige and Skoog (MS) medium, containing 1 mg l-1 kinetin and 0.25 mg l-1 NAA. Regenerated shoots were best rooted on MS medium containing 1 mg l-1 IBA and transferred to the greenhouse for flowering and seed set. As such, the present work is the first record of in vitro propagation of critically endangered C. tchihatcheffii, using immature zygotic embryos, and is a step forward towards conservation of this indigenous species.

  5. In vitro adventitious shoot regeneration via indirect organogenesis from petiole explants of Cassia angustifolia Vahl.-a potential medicinal plant.

    Science.gov (United States)

    Siddique, Iram; Anis, M; Aref, I M

    2010-11-01

    An effective protocol was developed for in vitro regeneration of the Cassia angustifolia via indirect organogenesis from petiole explants excised from 21-day-old axenic seedlings. Organogenic callus were induced on Murashige and Skoog (MS) medium supplemented with 5.0 µM 2,4-dichlorophenoxy acetic acid and 2.5 µM thidiazuron (TDZ). Adventitious shoot regeneration was achieved on MS medium supplemented with 5.0 µM TDZ as it induced 8.5 ± 0.98 shoots in 85% cultures. The number of shoots and shoot length was significantly enhanced when cultures were subcultured on auxin-cytokinin-containing medium. The highest number of shoots (12.5 ± 1.10) and shoot length (4.3 ± 0.20 cm) was recorded on MS medium supplemented with 5.0 µM TDZ and 1.5 µM indole-3-acetic acid. Regenerated shoots were rooted best on MS medium supplemented with 10.0 µM indole-3-butyric acid followed by their transfer to liquid MS filter paper bridge medium. The plants were successfully hardened off in sterile soilrite followed by their establishment in garden soil with 70% survival rate. The plants showed normal morphological characteristics similar to the field grown plants.

  6. Correlated response of in vitro regeneration capacity from different source of explants inCucumis melo.

    Science.gov (United States)

    Molina, R V; Nuez, F

    1995-01-01

    The variation among and within different populations of the regeneration ability from leaf, cotyledon and hypocotyl explants has been studied. A control population and two lines selected by their regeneration capacity from leaf explants were used. Significant differences among the plants of the control population,for the organogenic response, were detected. The regeneration capacity varies depending on the type of explant. Selection in order to improve the regeneration frequency from leaf explants also raises the organogenic response in the other explant types. This result suggests the presence of a partial common genetic system controlling the regeneration frequency of the diverse types of explants.

  7. Effects of invasive alien kahili ginger (Hedychium gardnerianum) on native plant species regeneration in a Hawaiian rainforest

    Science.gov (United States)

    Minden, V.; Jacobi, J.D.; Porembski, S.; Boehmer, H.J.

    2010-01-01

    Questions: Does the invasive alien Hedychium gardnerianum (1) replace native understory species, (2) suppress natural regeneration of native plant species, (3) increase the invasiveness of other non-native plants and (4) are native forests are able to recover after removal of H. gardnerianum. Location: A mature rainforest in Hawai'i Volcanoes National Park on the island of Hawai'i (about 1200 m. a.s.l.; precipitation approximately 2770mm yr-1). Study sites included natural plots without effects of alien plants, ginger plots with a H. gardnerianum-domimted herb layer and cleared plots treated with herbicide to remove alien plants. Methods: Counting mature trees, saplings and seedlings of native and alien plant species. Using nonparametric H-tests to compare impact of H. gardnerianum on the structure of different sites. Results: Results confirmed the hypothesis that H. gardnerianum has negative effects on natural forest dynamics. Lower numbers of native tree seedlings and saplings were found on ginger-dominated plots. Furthermore, H. gardnerianum did not show negative effects on the invasive alien tree species Psidium cattleianum. Conclusions: This study reveals that where dominance of H. gardnerianum persists, regeneration of the forest by native species will be inhibited. Furthermore, these areas might experience invasion by P. cattleianum, resulting in displacement of native canopy species in the future, leading to a change in forest structure and loss of other species dependent on natural rainforest, such as endemic birds. However, if H. gardnerianum is removed the native Hawaiian forest is likely to regenerate and regain its natural structure. ?? 2009 International Association for Vegetation Science.

  8. Wastewater minimization in multipurpose batch plants with a regeneration unit: multiple contaminants

    CSIR Research Space (South Africa)

    Adekola, O

    2011-12-01

    Full Text Available Wastewater minimization can be achieved by employing water reuse opportunities. This paper presents a methodology to address the problem of wastewater minimization by extending the concept of water reuse to include a wastewater regenerator...

  9. Establishment of a Rapid Plant Regeneration System in Physalis angulata L. through Axillary Meristems

    Directory of Open Access Journals (Sweden)

    Owk ANIEL KUMAR

    2015-12-01

    Full Text Available An optimal plant propagation method of Physalis angulata L., a medicinally important herbaceous plant species has been developed using axillary meristem explants. Shoot bud proliferation was initiated from axillary meristem explants cultured on MS medium supplemented with various concentrations of 0.5-2.5mg/L/(BAP/(Zeatin/(KIN. The maximum in vitro response of shooting frequency of explants (88.1% and shoots per explant (42 was achieved with medium containing 1.0mg/L BAP. Multiple shoot culture was established by repeated subculturing of the shoot buds of axillary meristems on shoot multiplication medium. Among the subculture media BAP in combination with 1.5mg/L (IAA+0.25mg/L(GA3 produced maximum shoots per explant (128±0.29 after two weeks of culture. Effective in vitro shoot elongation and rooting was achieved on 1.0mg/L(GA3 and 1.0mg/L(IBA, respectively. Most of the generated shoots were successfully transferred to soil under field conditions. The survival percentage of the transferred plants on soil was found to be 90 per cent.  This protocol can be used for commercial propagation and for future genetic improvement studies.

  10. Acupuncture plus Low-Frequency Electrical Stimulation (Acu-LFES) Attenuates Diabetic Myopathy by Enhancing Muscle Regeneration.

    Science.gov (United States)

    Su, Zhen; Robinson, Alayna; Hu, Li; Klein, Janet D; Hassounah, Faten; Li, Min; Wang, Haidong; Cai, Hui; Wang, Xiaonan H

    2015-01-01

    Mortality and morbidity are increased in patients with muscle atrophy resulting from catabolic diseases such as diabetes. At present there is no pharmacological treatment that successfully reverses muscle wasting from catabolic conditions. We hypothesized that acupuncture plus low frequency electric stimulation (Acu-LFES) would mimic the impact of exercise and prevent diabetes-induced muscle loss. Streptozotocin (STZ) was used to induce diabetes in mice. The mice were then treated with Acu-LFES for 15 minutes daily for 14 days. Acupuncture points were selected according to the WHO Standard Acupuncture Nomenclature guide. The needles were connected to an SDZ-II electronic acupuncture device delivering pulses at 20Hz and 1mA. Acu-LFES prevented soleus and EDL muscle weight loss and increased hind-limb muscle grip function in diabetic mice. Muscle regeneration capacity was significantly increased by Acu-LFES. The expression of Pax7, MyoD, myogenin and embryo myosin heavy chain (eMyHC) was significantly decreased in diabetic muscle vs. control muscle. The suppressed levels in diabetic muscle were reversed by Acu-LFES. The IGF-1 signaling pathway was also upregulated by Acu-LFES. Phosphorylation of Akt, mTOR and p70S6K were downregulated by diabetes leading to a decline in muscle mass, however, Acu-LFES countered the diabetes-induced decline. In addition, microRNA-1 and -206 were increased by Acu-LFES after 24 days of treatment. We conclude that Acu-LFES is effective in counteracting diabetes-induced skeletal muscle atrophy by increasing IGF-1 and its stimulation of muscle regeneration.

  11. Acupuncture plus Low-Frequency Electrical Stimulation (Acu-LFES Attenuates Diabetic Myopathy by Enhancing Muscle Regeneration.

    Directory of Open Access Journals (Sweden)

    Zhen Su

    Full Text Available Mortality and morbidity are increased in patients with muscle atrophy resulting from catabolic diseases such as diabetes. At present there is no pharmacological treatment that successfully reverses muscle wasting from catabolic conditions. We hypothesized that acupuncture plus low frequency electric stimulation (Acu-LFES would mimic the impact of exercise and prevent diabetes-induced muscle loss. Streptozotocin (STZ was used to induce diabetes in mice. The mice were then treated with Acu-LFES for 15 minutes daily for 14 days. Acupuncture points were selected according to the WHO Standard Acupuncture Nomenclature guide. The needles were connected to an SDZ-II electronic acupuncture device delivering pulses at 20Hz and 1mA. Acu-LFES prevented soleus and EDL muscle weight loss and increased hind-limb muscle grip function in diabetic mice. Muscle regeneration capacity was significantly increased by Acu-LFES. The expression of Pax7, MyoD, myogenin and embryo myosin heavy chain (eMyHC was significantly decreased in diabetic muscle vs. control muscle. The suppressed levels in diabetic muscle were reversed by Acu-LFES. The IGF-1 signaling pathway was also upregulated by Acu-LFES. Phosphorylation of Akt, mTOR and p70S6K were downregulated by diabetes leading to a decline in muscle mass, however, Acu-LFES countered the diabetes-induced decline. In addition, microRNA-1 and -206 were increased by Acu-LFES after 24 days of treatment. We conclude that Acu-LFES is effective in counteracting diabetes-induced skeletal muscle atrophy by increasing IGF-1 and its stimulation of muscle regeneration.

  12. Vegetative propagation of Quercus suber L. by somatic embryogenesis. II. Plant regeneration from selected cork oak trees.

    Science.gov (United States)

    Hernández, I; Celestino, C; Alegre, J; Toribio, M

    2003-04-01

    The regeneration of somatic seedlings from selected 100-year-old cork oak trees is reported. The induction of somatic embryogenesis from leaves of epicormic shoots was significantly affected by genotype, harvesting time and their interaction. Leaves from all five selected trees produced somatic embryos when the segments of branches used as sources of epicormic shoots were collected in May. Genotype, but not the level of photosynthetically active radiation, affected the proliferation of the embryogenic lines and the number of detachable embryos that could be obtained from them. Genotype also affected several steps leading to conversion of somatic embryos, from germination to complete acclimatisation of somatic seedlings. Almost 40% of the somatic embryos from all lines germinated, showing coordinated root and shoot growth. Although the mean percentage of recovery for the whole process was low, plants could be regenerated from four of the five trees tested.

  13. Loss of CMD2‐mediated resistance to cassava mosaic disease in plants regenerated through somatic embryogenesis

    Science.gov (United States)

    Chauhan, Raj Deepika; Wagaba, Henry; Moll, Theodore; Alicai, Titus; Miano, Douglas; Carrington, James C.; Taylor, Nigel J.

    2016-01-01

    Summary Cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) are the two most important viral diseases affecting cassava production in Africa. Three sources of resistance are employed to combat CMD: polygenic recessive resistance, termed CMD1, the dominant monogenic type, named CMD2, and the recently characterized CMD3. The farmer‐preferred cultivar TME 204 carries inherent resistance to CMD mediated by CMD2, but is highly susceptible to CBSD. Selected plants of TME 204 produced for RNA interference (RNAi)‐mediated resistance to CBSD were regenerated via somatic embryogenesis and tested in confined field trials in East Africa. Although micropropagated, wild‐type TME 204 plants exhibited the expected levels of resistance, all plants regenerated via somatic embryogenesis were found to be highly susceptible to CMD. Glasshouse studies using infectious clones of East African cassava mosaic virus conclusively demonstrated that the process of somatic embryogenesis used to regenerate cassava caused the resulting plants to become susceptible to CMD. This phenomenon could be replicated in the two additional CMD2‐type varieties TME 3 and TME 7, but the CMD1‐type cultivar TMS 30572 and the CMD3‐type cultivar TMS 98/0505 maintained resistance to CMD after passage through somatic embryogenesis. Data are presented to define the specific tissue culture step at which the loss of CMD resistance occurs and to show that the loss of CMD2‐mediated resistance is maintained across vegetative generations. These findings reveal new aspects of the widely used technique of somatic embryogenesis, and the stability of field‐level resistance in CMD2‐type cultivars presently grown by farmers in East Africa, where CMD pressure is high. PMID:26662210

  14. Transformation of maize embryogenic calli mediated by ultrasonication and regeneration of fertile transgenic plants

    Institute of Scientific and Technical Information of China (English)

    张宏; 王国英; 谢友菊; 戴景瑞; 许宁; 赵南明; 李太源; 田颖川; 乔利亚; 莽克强

    1997-01-01

    An insecticidal protein gene isolated from Bacillus thuringiensis was transferred into maize by using ultrasonication. The fertile transgenic plants and their progeny were obtained. The Southern hybridization results indi-cated that the foreign gene had integrated into the maize genome. It has been found that the acoustic intensity and the duration of treatment are the important parameters influencing transformation efficiency by ultrasonication. The maxi-mum relative transformation frequency of 34. 1 % was achieved after 30 min of sonication at 0. 5 W/cm2 acoustic inten-sity. With appropriate parameters the ultrasonication ran make a number of micropores formed on the cell surface and minimize the treatment damage to the foreign DNA molecules, thus facilitating the DNA molecules to enter the cells.

  15. Plant regeneration from encapsulated embryoids and an embryogenic mass of pistachio, Pistacia vera L.

    Science.gov (United States)

    Onay, A; Jeffree, C E; Yeoman, M M

    1996-05-01

    Pieces of an embryogenic mass (EMS) induced in culture from immature fruits of pistachio, Pistacia vera L., were encapsulated into calcium alginate beads. Somatic embryos were also encapsulated individually into calcium alginate beads to produce synthetic seeds. The viability of the encapsulated EMS and somatic embryos was investigated immediately following encapsulation, and after storage for 60 days at 4°C. The encapsulated-stored EMS fragments recovered their original proliferative capacity after two months storage following two sub-cultures, but non-encapsulated-stored EMS failed to recover. The conversion frequency of synthetic seeds to seedling plants was 14% after storage for 60 days at 4°C, from which it may be concluded that encapsulation is a practical procedure for short-term storage of embryogenic pistachio tissue, and may be applicable to the preservation of desirable elite genotypes.

  16. Chloroplast ultra structure, photosynthesis and enzyme activities in regenerated plants of Stevia rebaudiana (Bert.) Bertoni as influenced by copper sulphate in the medium.

    Science.gov (United States)

    Jain, Pourvi; Kachhwaha, Sumita; Kothari, S L

    2014-09-01

    Stevia rebaudiana (Bert.) Bertoni is an important medicinal plant used as noncaloric commercial sweetener. Plants regenerated with higher levels of copper sulphate in the medium exhibited enhanced activity of peroxidase and polyphenoloxidase (PPO) enzymes. Transmission electron microscopy (TEM) revealed increase in size and number of electron dense inclusions in the chloroplasts of plants regenerated at optimised level of copper sulphate (0.5 microM) in the medium. There was decrease in chlorogenic acid (CGA) content. Chl-a-fluorescence transient pattern (OJIP) showed that the photosynthesis process was more efficient at 0.5 microM CuSO4 in the medium.

  17. Agrobacterium-mediated transformation of apple (Malus x domestica Borkh.): an assessment of factors affecting regeneration of transgenic plants.

    Science.gov (United States)

    De Bondt, A; Eggermont, K; Penninckx, I; Goderis, I; Broekaert, W F

    1996-03-01

    We have previously developed a protocol for efficient gene transfer and regeneration of transgenic calli following cocultivation of apple (cv. Jonagold) explants with Agrobacterium tumefaciens (De Bondt et al. 1994, Plant Cell Reports 13: 587-593). Now we report on the optimization of postcultivation conditions for efficient and reproducible regeneration of transgenic shoots from the apple cultivar Jonagold. Factors which were found to be essential for efficient shoot regeneration were the use of gelrite as a gelling agent and the use of the cytokinin-mimicing thidiazuron in the selective postcultivation medium. Improved transformation efficiencies were obtained by combining the hormones thidiazuron and zeatin and by using leaf explants from in vitro grown shoots not older than 4 weeks after multiplication. Attempts to use phosphinothricin acetyl transferase as a selectable marker were not successful. Using selection on kanamycin under optimal postcultivation conditions, about 2% of the leaf explants developed transgenic shoots or shoot clusters. The presence and expression of the transferred genes was verified by β-glucuronidase assays and Southern analysis. The transformation procedure has also been succesfully applied to several other apple cultivars.

  18. In vitro Regeneration of Plantlets from Leaf and Nodal explants of Aristolochia indica L.- An Important Threatened Medicinal Plant

    Institute of Scientific and Technical Information of China (English)

    Pramod V. Pattar; M.Jayaraj

    2012-01-01

    Objective: An efficient reproducible protocol has been developed for in vitro regeneration of plantlets from leaf and nodal explants of Aristolochia indica L. Methods: Wild grown plants Aristolochia indica L. were collected and grown in the departmental garden. Leaf and nodal segments (0.5-1.0 cm) from young healthy plants were first washed thoroughly under running tap water for 15 - 20 minutes and then treated with liquid detergent [5% (v/v) Tween-20] for 5-10 minutes. Later these explants were washed with double-distilled water for 5 minutes. Subsequently, explants were immersed in 70% (v/v) ethanol for 2 - 3 minutes and washed with sterile glass double distilled water for 2-3 times. Eventually, the explants were treated with an aqueous solution of 0.1% (w/v) HgCl2 for 1 - 2 minutes and rinsed for two-to-three times in sterile ddH2O to remove all traces of HgCl2. The sterilized explants were inoculated aseptically onto solid basal Murashige and Skoog’s medium with different concentrations and combinations of BAP and NAA for in vitro regeneration of plants. Results: Both leaf and nodal explants cultured on MS medium supplemented with 0.8 mg/L BAP developed into mass of callus. These calli were subcultured for the induction of shoots and roots. Shoots were induced from both calli on MS medium supplemented with 0.8 mg/L BAP+0.5 mg/L NAA. Roots were induced from in vitro shoots on MS medium supplemented with 0.8 mg/L NAA for 4 weeks. Nodal explants were more regenerative with 95 % response compared to leaf explants with 85%. Finally, these in vitro regenerated plantlets were hardened, acclimatised and successfully transferred to the field. Conclusions: The present protocol for in vitro regeneration of Aristolochia indica L. can be used to make this plant available throughout the year for traditional healers, pharmaceutical usages, germplasm conservation, commercial cultivation, and also for the production of secondary metabolites.

  19. An efficient method for Agrobacterium-mediated genetic transformation and plant regeneration in cumin (Cuminum cyminum L.).

    Science.gov (United States)

    Pandey, Sonika; Mishra, Avinash; Patel, Manish Kumar; Jha, Bhavanath

    2013-09-01

    Cumin is an annual herbaceous medicinally important plant having diverse applications. An efficient and reproducible method of Agrobacterium-mediated genetic transformation was herein established for the first time. A direct regeneration method without callus induction was optimised using embryos as explant material in Gamborg's B5 medium supplemented with 0.5-μM 6-benzyladenine and 2.0-μM α-naphthalene acetic acid. About 1,020 embryos (a mean of 255 embryos per batch) were used for the optimisation of transformation conditions. These conditions were an Agrobacterium cell suspension of 0.6 OD600, a co-cultivation time of 72 h, 300-μM acetosyringone and wounding of explants using a razor blade. Pre-cultured elongated embryos were treated using optimised conditions. About 720 embryos (a mean of 180 embryos per batch) were used for transformation and 95 % embryos showed transient β-glucuronidase expression after co-cultivation. Putative transformed embryos were cultured on B5 medium for shoot proliferation and 21 regenerated plants were obtained after selection and allowed to root. T0 plantlets showed β-glucuronidase expression and gene integration was confirmed via PCR amplification of 0.96 and 1.28 kb fragments of the hygromycin-phosphotransferase II and β-glucuronidase genes, respectively. In this study, a transformation efficiency of 1.5 % was demonstrated and a total of 11 transgenic plants were obtained at the hardening stage, however, only four plants acclimatised during hardening. Gene copy number was analysed by Southern blot analysis of hardened plants and single-copy gene integration was observed. This is the first successful attempt of Agrobacterium-mediated genetic transformation of cumin.

  20. Optimized growth and plant regeneration for callus of Lilium longiflorum cv. Nellie White

    Science.gov (United States)

    The rates of growth and regeneration were compared for compact callus, friable callus, and suspension cells of Lilium longiflorum cv. Nellie White to determine the optimal culture conditions. The fresh weight was higher for compact callus induced from bulb scales cultured on Murashige and Skoog’s m...

  1. Plant regeneration from protoplasts of immature Vigna sinensis cotyledons via somatic embryogenesis.

    Science.gov (United States)

    Li, X B; Xu, Z H; Wei, Z M

    1995-12-01

    Protoplasts were isolated from immature cotyledons of Vigna sinensis and cultured in a modified MS Liquid medium containing 0. 2 mg/l 2, 4-dichlorophenoxyacetic acid (2, 4-D), 1 mg/l naphthaleneacetic acid (NAA) and 0. 5 mg/l 6-benzylaminopurine (BAP) in the dark at a density of 1 × 10(5)/ml. The protoplasts began to divide in 3-5 days. Sustained cell division resulted in formation of cell clusters and small calli, with the cell division frequency and plating efficiency of cell colonies reaching 27. 7% and 1. 7% respectively. When calli of 2 mm in size were transferred onto MSB medium (MS salts and B5 vitamins) containing 500mg/l NaCl, 500 mg/ 1 casein hydrolysate (CH), 2 mg/l 2,4-D and 0. 5 mg/l BAP for further growth, approximately 5% of the calli developed embryogenically. The embryogenic calli were selected and subcultured on the same composition of MSB medium and were able to maintain somatic embryogenesis capacity in subculture for a long time. When the calli were moved to MSB medium with 0. 1 mg/l indole-3-acetic acid (IAA), 0. 5mg/l kinetin(KT), 3-5% mannitol and 2% sucrose in the light, many somatic embryos formed from the calli. Only part of the embryoids developed further to the cotyledonary stage, and the others died at the globular, heart-shaped or torpedo stages. Finally, some cotyledonary embryoids germinated and developed into plants or shoots. The shoots were readily rooted on 1/2 strength MS medium with 0. 1-0.3 mg/l indole-3-butyric acid (IBA). The plants grew well in soil and were fertile.

  2. Exergoeconomic performance optimization of an endoreversible intercooled regenerated Brayton cogeneration plant. Part 1: Thermodynamic model and parameter analyses

    Directory of Open Access Journals (Sweden)

    Lingen Chen, Bo Yang, Fengrui Sun

    2011-03-01

    Full Text Available A thermodynamic model of an endoreversible intercooled regenerative Brayton heat and power cogeneration plant coupled to constant-temperature heat reservoirs is established by using finite time thermodynamics in Part 1 of this paper. The heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are taken into account. The finite time exergoeconomic performance of the cogeneration plant is investigated. The analytical formulae about dimensionless profit rate and exergetic efficiency are derived. The numerical examples show that there exists an optimal value of intercooling pressure ratio which leads to an optimal value of dimensionless profit rate for the fixed total pressure ratio. There also exists an optimal total pressure ratio which leads to a maximum profit rate for the variable total pressure ratio. The effects of intercooling, regeneration and the ratio of the hot-side heat reservoir temperature to environment temperature on dimensionless profit rate and the corresponding exergetic efficiency are analyzed. At last, it is found that there exists an optimal consumer-side temperature which leads to a double-maximum dimensionless profit rate. The profit rate of the model cycle is optimized by optimal allocation of the heat conductance of the heat exchangers in Part 2 of this paper.

  3. A comparative assessment on regeneration status of indigenous woody plants in Eucalyptus grandis plantation and adjacent natural forest

    Institute of Scientific and Technical Information of China (English)

    Shiferaw Alem; Tadesse Woldemariam

    2009-01-01

    Diversity, density and species composition of naturally regenerated woody plants under Eucalyptus grandis plantation and the adjacent natural forest were investigated and compared. Twenty plots, with an area of 20 m× 20 m for each, were established in both of E. Grandis plantation and adjacent natural forest, independently. In each plot, species name, abundance, diameter and height were recorded. Numbers of seedling were collected in five sub-plots (4 m2) within each major plot. A total of 46 species in the plantation, and 52 species in the natural forest, which belongs to 36 families were recorded. The diversity of species (H') is 2.19 in the plantation and 2.74 in the natural forest. The density of understory woody plant was 3842 stems/ha in the plantation and 4122 stems/ha in the natural forest. The densities of seedlings in the natural forest and the plantation were 8101 stems/ha and 4151 stems/ha, respectively. High similarity of woody species composition was found between the natural forest and the plantation. The E. Grandis plantation was found favoring the regeneration and growth of Millitia ferruginia and Coffea arabica in a much better way than other underneath woody species.

  4. Obtaining marker-free transgenic soybean plants with optimal frequency by constructing a three T-DNA binary vector

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Obtaining marker-free plants with high efficiency will benefit the environmental release of transgenic crops.To achieve this point,a binary vector with three T-DNAs was constructed using several mediate plasmids,in which one copy of BAR gene expression cassette and two copies of VIP1 gene expression cassette were included.EHA101 Agrobacterium strain harboring the final construct was applied to transform soybean cotyledon nodes.Through 2-3 months regeneration and selection with 3-5 mg·L-1 glufosinate,transgenic soybean plants were obtained at 0.83%-3.16%,and the co-transformation efficiency of both genes in the same individual reached up to 86.4%,based on the southern blot test.Using PCR analysis,southern blot and northern blot tests,as well as leaf painting of herbicide in T1 progenies,41 plants were eliminated of BAR gene with the frequency of 7.6%.Among the T1 populations tested,the loss of the alien genes happened in 22.7% lines,the silence of the BAR gene took place in 27.3% lines,and VIP1 gene silence existed in 37.1% marker-free plants.The results also suggested that the plasmid with three T-DNAs might be an ideal vector to generate marker-free genetically modified organisms.

  5. [Clonal micropropagation of a rare species Hedysarum theinum Krasnob (Fabaceae) and assessment of the genetic stability of regenerated plants using ISSR markers].

    Science.gov (United States)

    Erst, A A; Svyagina, N S; Novikova, T I; Dorogina, O V

    2015-02-01

    In the present study, a protocol was developed for the in vitro propagation of a rare medicinal plant, Hedysarum theinum (tea sweetvetch), from axillary buds, and identification of the regenerants was performed with the use of ISSR markers. It was demonstrated that Gamborg and Eveleigh medium supplemented with 5 μM 6-benzylaminopurine was the best for H. theinum for initial multiplication. On the other hand, half-strength Murashige and Skoog (MS) basal medium supplemented with 7 μM α-naphthaleneacetic acid proved to be the best for explant rooting. Molecular genetic analysis of the H. theinum mother plants and the obtained regenerants was performed with six ISSR markers. Depending on the primer, four to ten amplified fragments with sizes ranging from 250 to 3000 bp were identified. Our results confirmed the genetic stability of regenerants obtained in five passages and their identity to the mother plant.

  6. Frequency and abundance patterns of plant dispersal systems in Colombian forests and their relationships with the geographic regions of the country

    Directory of Open Access Journals (Sweden)

    Diego Felipe Correa Gomez et al.

    2013-07-01

    Full Text Available The study of plant dispersal systems improves our understanding of forest regeneration, the dynamics of plant populations and the ecological relationships that emerge within ecosystems. In this study we analyzed the patterns of seed dispersal systems for Colombia, in relation to the Amazonian, Andean, Caribbean, Upper Magdalena, Middle Magdalena, Orinoco and Pacific geographic regions. Based on information on identity and abundance of plants found in 101 one hectare vegetation plots, we explored the changes in the relative frequency and relative abundance of plant dispersal systems among the geographic regions. Additionally, we explored the floristic affinities between the regions, as well as the representativeness of families and genera per dispersal system. Endozoochory was highly represented at different taxonomic levels (species, genus, family, and its relative importance changed among the different geographic regions. Those changes could be explained by ecological differences between the regions.

  7. An improved plant regeneration and Agrobacterium - mediated transformation of red pepper (Capsicum annuum L.).

    Science.gov (United States)

    Kumar, R Vinoth; Sharma, V K; Chattopadhyay, B; Chakraborty, S

    2012-10-01

    Capsicum annuum (red pepper) is an important spice cum vegetable crop in tropical and subtropical countries. Here, we report an effective and reproducible auxin free regeneration method for six different red pepper cultivars (ACA-10, Kashi Anmol, LCA-235, PBC-535, Pusa Jwala and Supper) using hypocotyl explants and an efficient Agrobacterium-mediated transformation protocol. The explants (hypocotyls, cotyledonary leaves and leaf discs) collected from axenic seedlings of six red pepper cultivars were cultured on either hormone free MS medium or MS medium supplemented with BAP alone or in combination with IAA. Inclusion of IAA in the regeneration medium resulted in callus formation at the cut ends of explants, formation of rosette leaves and ill defined shoot buds. Regeneration of shoot buds could be achieved from hypocotyls grown in MS medium supplemented with different concentrations of BAP unlike other explants which failed to respond. Incorporation of GA3 in shoot elongation medium at 0.5 mg/l concentration enhanced the elongation in two cultivars, LCA-235 and Supper, while other cultivars showed no significant response. Chilli cultivar, Pusa Jwala was transformed with βC1 ORF of satellite DNA β molecule associated with Chilli leaf curl Joydebpur virus through Agrobacterium tumefaciens. Transgene integration in putative transformants was confirmed by PCR and Southern hybridization analysis.

  8. Cepstrum-based operational modal analysis revisited: A discussion on pole-zero models and the regeneration of frequency response functions

    Science.gov (United States)

    Smith, Wade A.; Randall, Robert B.

    2016-10-01

    Operational modal analysis (OMA) seeks to determine a structure's dynamic characteristics from response-only measurements, which comprise both excitation and transmission path effects. The cepstrum has been used successfully in a number of applications to separate these source and path effects, after which the poles and zeros of the transfer function can be obtained via a curve-fitting process. The contributions from the individual poles and zeros can then be added (in log magnitude) to regenerate the frequency response function (FRF). Cepstrum-based OMA was originally developed in the 1980s and 90s, but there have been a number of recent developments that warrant discussion and explanation, and this is the basis of the present paper, which focusses on the FRF regeneration process and on a number of broader points explaining FRFs from a pole-zero perspective. The FRF regenerated from identified poles and zeros is subject to magnitude distortion from the effects of truncation, i.e., from the residual effects of out-of-band poles and zeros. As long as a reference FRF is available - for example from conventional experimental modal analysis or from a finite element model - this distortion can be corrected for using a magnitude equalisation curve. This paper discusses the nature of this equalisation curve, and gives recommendations on how best to obtain it. Other topics covered in the discussion are: the required distribution of poles and zeros for the successful regeneration of FRFs; node points and weak modes in a pole-zero model; the differences in pole-zero distribution between receptance, mobility and accelerance FRF forms; and, how to deal with the very low frequency region when regenerating FRFs. Special consideration is given to the identification of zeros - often masked by noise in response measurements - using transmissibility estimation. It is hoped that the discussion will assist in the application of cepstrum-based OMA methods and will lead to improved

  9. Characterization of biomass production, cytology and phenotypes of plants regenerated from embryogenic callus cultures of Pennisetum americanum x P. purpureum (hybrid triploid napiergrass).

    Science.gov (United States)

    Rajasekaran, K; Schank, S C; Vasil, I K

    1986-11-01

    Five hundred and twenty-four plants of a triploid, sexually sterile hybrid napiergrass (Pennisetum americanum x P. purpureum; 3x=21) were regenerated from embryogenic callus cultures obtained from segments of young inflorescences. Replicated field trials were conducted for two consecutive years to compare the biomass yield, phenotype and cytology of tissue culture regenerants (TC) and vegetatively propagated (V) plants. In the first year total biomass yield of TC plants was significantly greater than V plants but there was no significant difference in the second year. TC plants had more tillers compared to V plants. V plants did not show any morphological variability. The TC population also exhibited a high degree of phenotypic stability (96%). There were 23 phenotypic variants in the TC population of 524, most of them being more dwarf and late-flowering. Detailed morphological analysis of the TC-variant plants suggests that they very likely arose from only a few variant cell lines. Cytological analysis indicated stability of the triploid status in randomly selected regenerants. Two of the morphological variants were hexaploids (6x=42). It is concluded that embryogenic callus cultures can provide useful alternative for the rapid propagation of hybrid napier-grass which is commonly propagated by cuttings.

  10. Phenotypic variability in the field of Saccharum spp. hybrid cv. ‘C87-51’plants regenerated via somatic embryogenesis

    Directory of Open Access Journals (Sweden)

    Marisol Freire-Seijo

    2016-10-01

    Full Text Available Sugarcane (Saccharum spp. is a crop of great economic importance that has been propagated by tissue culture through organogenesis and somatic embryogenesis. The present research had as objective to determine the phenotypic variability in the field of sugar cane cv. 'C87-51' plants obtained by somatic embryogenesis in liquid culture media. Plants regenerated from somatic embryos were planted in the field next to plants propagated via organogenesis and from cuttings that were used as control. The evaluations were carried out seven months after planting in cane plant and first shoot and the variables evaluated were stem height, stem diameter, number of stems per seedlings, number of active leaves per stem and Brix. Besides, morphological characteristics were described. Plants out of type were not found in the evaluated populations. The results demonstrated that the plant regeneration pathway significantly influences the development of plants under field conditions. The propagation of sugarcane plants cv. 'C87-51' by somatic embryogenesis in liquid culture medium only induces phenotypic changes in field associated with in vitro rejuvenation similar to those previously reported for plants obtained by organogenesis. Therefore, it can be used as a method of mass propagation of plants.   Keywords: bioreactor, somatic embryos, somaclonal variation, sugarcane

  11. Improved Frequency Control from Wind Power Plants Considering Wind Speed Variation

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Das, Kaushik; Altin, Müfit;

    2016-01-01

    A fast frequency controller (FFC) for wind power plants (WPPs), which produces a temporary overloading power reference based on frequency deviation and rate of change of frequency, is proposed in this paper. Contrary to standard controllers proposed in the literature, the gains of the FFC...

  12. Plant diversity, population structure, and regeneration status in dis-turbed tropical forests in Assam, northeast India

    Institute of Scientific and Technical Information of China (English)

    Gitamani Dutta; Ashalata Devi

    2013-01-01

    We investigated the plant population structure and the phy-tosociological and regeneration status in two disturbed tropical forests in Assam Province, the Hojai Reserve Forest and Kumorakata Reserve Forest. A total of 166 species (80 trees, 20 shrubs and 66 herbs) of 136 genera and 63 families were recorded in both study sites. The disturbance index at the two sites, Kumorakata Reserve Forest and Hojai Reserve Forest, were recorded at 11.4% and 3.70% respectively. Reverse J-shaped population curve and exploitation of tree species in higher girth classes were recorded at both study sites. In the girth classes (10−30 cm, 30−60 cm, 60−90 cm and 90−120 cm in size) the percentage of cut stump density was higher than the percentage of individual living trees. The 18% (Kumorakata Reserve Forest) and 7% (Hojai Reserve Forest) spe-cies were recorded as “not regenerating.” Illegal felling and over-exploitation of forest resources may lead to species-specific changes in the population structure and can alter the future structure and composi-tion of the forests.

  13. Insights into ascorbate regeneration in plants: investigating the redox and structural properties of dehydroascorbate reductases from Populus trichocarpa.

    Science.gov (United States)

    Lallement, Pierre-Alexandre; Roret, Thomas; Tsan, Pascale; Gualberto, José M; Girardet, Jean-Michel; Didierjean, Claude; Rouhier, Nicolas; Hecker, Arnaud

    2016-03-15

    Dehydroascorbate reductases (DHARs), enzymes belonging to the GST superfamily, catalyse the GSH-dependent reduction of dehydroascorbate into ascorbate in plants. By maintaining a reduced ascorbate pool, they notably participate to H2O2 detoxification catalysed by ascorbate peroxidases (APXs). Despite this central role, the catalytic mechanism used by DHARs is still not well understood and there is no supportive 3D structure. In this context, we have performed a thorough biochemical and structural analysis of the three poplar DHARs and coupled this to the analysis of their transcript expression patterns and subcellular localizations. The transcripts for these genes are mainly detected in reproductive and green organs and the corresponding proteins are expressed in plastids, in the cytosol and in the nucleus, but not in mitochondria and peroxisomes where ascorbate regeneration is obviously necessary. Comparing the kinetic properties and the sensitivity to GSSG-mediated oxidation of DHAR2 and DHAR3A, exhibiting 1 or 3 cysteinyl residues respectively, we observed that the presence of additional cysteines in DHAR3A modifies the regeneration mechanism of the catalytic cysteine by forming different redox states. Finally, from the 3D structure of DHAR3A solved by NMR, we were able to map the residues important for the binding of both substrates (GSH and DHA), showing that DHAR active site is very selective for DHA recognition and providing further insights into the catalytic mechanism and the roles of the additional cysteines found in some DHARs.

  14. Exergoeconomic performance optimization of an endoreversible intercooled regenerated Brayton cogeneration plant. Part 2: Heat conductance allocation and pressure ratio optimization

    Directory of Open Access Journals (Sweden)

    Bo Yang, Lingen Chen, Fengrui Sun

    2011-03-01

    Full Text Available Finite time exergoeconomic performance of an endoreversible intercooled regenerative Brayton cogeneration plant is optimized based on the model which is established using finite time thermodynamic in Part 1 of this paper. It is found that the optimal heat conductance allocation of the regenerator is zero. When the total pressure ratio and the heat conductance allocation of the regenerator are fixed, it is shown that there exist an optimal intercooling pressure ratio, and a group of optimal heat conductance allocations among the hot-, cold- and consumer-side heat exchangers and the intercooler, which correspond to a maximum dimensionless profit rate. When the total pressure ratio is variable, there exists an optimal total pressure ratio which corresponds to a double-maximum dimensionless profit rate, and the corresponding exergetic efficiency is obtained. The effects of the total heat exchanger conductance, price ratios and the consumer-side temperature on the double-maximum dimensionless profit rate and the corresponding exergetic efficiency are discussed. It is found that there exists an optimal consumer-side temperature which corresponds to a thrice-maximum dimensionless profit rate.

  15. Insitu bioaugmentation of nitrification in the regeneration zone: practical application and experiences at full-scale plants.

    Science.gov (United States)

    Krhutkovi, O; Novák, L; Pachmanová, L; Benáková, A; Wanner, J; Kos, M

    2006-01-01

    Nitrification is the rate-limiting process in the design of activated sludge process. It is especially unstable during the winter season (when the temperature of activated sludge mixed liquor drops below 13 degrees C). It is therefore difficult to meet the ammonia effluent standards in winter. The common way to compensate for low nitrification rates at low temperatures is to increase sludge retention time (SRT). However, the increase of SRT is accompanied by negative factors such as elevated sludge concentration, higher sludge loading of secondary clarifiers, formation of unsettleable microflocs, etc. The low performance of nitrification at low temperatures can also be compensated for by enhancing the nitrification population in activated sludge. This paper describes such a method called bioaugmentation of nitrification in situ. This procedure takes place in a so-called regeneration tank, which is situated in the return activated sludge stream. The results of the operation of two wastewater treatment plants with regeneration zones are described in this paper, together with some economic evaluation of the bioaugmentation method.

  16. 南瓜未受精胚珠的离体培养及植株再生%In Vitro Culture of Pumpkin Unfertilized Ovules and Plant Regeneration

    Institute of Scientific and Technical Information of China (English)

    孙守如; 章鹏; 胡建斌; 孙利萍; 张曼; 孙治强

    2013-01-01

    We used unfertilized ovules of the pumpkin cultivar 'Experiment 1' as explants to examine the effect of combinations and concentrations of growth regulators, different developmental periods, high-temperature pretreatment, and AgNO3 concentrations on embryoid induction. The combination of 2,4-D, NAA, and 6-BA favoured embryoid induction; the medium with the best effect was Murishige and Skoog (MS)+1.0 mg·L-12,4-D+0.25 mg·L-1NAA+0.5 mg·L-1 6-BA, for 31.1% embryoid induction. The flowering ovules for the day showed the highest frequency of embryoid induction (26.7%) and the lowest frequency of callus formation (<5%). The explants treated with darkness and high temperature (35℃) for 5 days showed the best embryoid induction, 32.2%. However, the addition of AgNO3 remarkably inhibited embryoid induction. Transfer of embryoids to plant-regeneration medium led to the highest regeneration frequency, 64.3%. Plant regeneration expressed a typical pathway as for embryogenesis. Cytologic observations revealed that embryoids probably derived from cells close to the micropyle (i.e., ovums or synergids).%以南瓜(Cucurbita moschata)品种试验1号为材料,以未受精胚珠为外植体,研究了激素种类、外植体发育时期、高温预处理时间和AgNO3浓度对胚状体诱导的影响.结果表明,2,4-D、NAA和6-BA组合有利于胚状体的形成,出胚效果最好的培养基为MS+1.0 mg·L-12,4-D+0.25 mg·L-1NAA+0.5 mg·L-16-BA,出胚率达31.1%;雌花开放当天的胚珠出胚率最高(26.7%),且愈伤组织形成频率低(<5%);外植体在黑暗、高温(35℃)条件下处理5天有利于胚状体的形成,出胚率为32.2%.培养基中添加AgNO3对胚状体形成的抑制作用明显.胚状体转移至成苗培养基后可形成正常小苗,出苗率最高可达64.3%,植株再生过程经历了典型的胚胎发育途径.细胞学观察结果表明,胚状体极有可能起源于胚囊珠孔端的细胞,即卵细胞或助细胞.

  17. Carbon source dependent somatic embryogenesis and plant regeneration in cotton, Gossypium hirsutum L. cv. SVPR2 through suspension cultures.

    Science.gov (United States)

    Ganesan, M; Jayabalan, N

    2005-10-01

    Highly reproducible and simple protocol for cotton somatic embryogenesis is described here by using different concentrations of maltose, glucose, sucrose and fructose. Maltose (30 g/l) is the best carbon source for embryogenic callus induction and glucose (30 g/l) was suitable for induction, maturation of embryoids and plant regeneration. Creamy white embryogenic calli of hypocotyl explants were formed on medium containing MS basal salts, myo-inositol (100 mg/l), thiamine HCI (0.3 mg/l), picloram (0.3 mg/l), Kin (0.1 mg/l) and maltose (30 g/l). During embryo induction and maturation, accelerated growth was observed in liquid medium containing NH3NO4 (1 g/l), picloram (2.0 mg/l), 2 ip (0.2 mg/l), Kin (0.1 mg/l) and glucose (30 g/l). Before embryoid induction, large clumps of embryogenic tissue were formed. These tissues only produced viable embryoids. Completely matured somatic embryos were germinated successfully on the medium fortified with MS salts, myo-inositol (50 mg/l), thiamine HCl (0.2 mg/l), GA3 (0.2 mg/l), BA (1.0 mg/l) and glucose (30 g/l). Compared with earlier reports, 65% of somatic embryo germination was observed. The abnormal embryo formation was highly reduced by using glucose (30 g/l) compared to other carbon sources. The regenerated plantlets were fertile but smaller in height than the seed derived control plants.

  18. The development of an efficient cultivar-independent plant regeneration system from callus derived from both apical and non-apical root segments of garlic (Allium sativum L.)

    NARCIS (Netherlands)

    Zheng, S.J.; Henken, G.; Krens, F.A.; Kik, C.

    2003-01-01

    Callus induction and later plant regeneration were studied in four widely grown garlic (Allium sativum L.) cultivars from Europe. Root segments from in vitro plantlets were used as starting material. In addition to cultivar effects, the effects of auxin and cytokinin levels and the position of the s

  19. High Efficiency Somatic Embrogenesis and Plant Regeneration in Suspension Cultures of an Ornamental Ginger Hybrid (Hedychium muluense x cv ‘Starburst’)

    Science.gov (United States)

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of an ornamental ginger hybrid, Hedychium muluense x cv ‘Starburst’. H. muluense is a dwarf species and ‘Starburst’ is a hybrid cultivar with white and very fragrant flowers in a circular, wheel-like arrang...

  20. Efficient in vitro plant regeneration from immature zygotic embryos of pearl millet [Pennisetum glaucum (L.) R. Br.] and Sorghum bicolor (L.) Moench

    CSIR Research Space (South Africa)

    Oldach, KH

    2001-07-01

    Full Text Available ) and various cytokinins; (2) the addition of AgNO3; (3) the use of maltose or sucrose as a carbon source. Modifications in the phytohormones alone resulted in the regeneration of fertile sorghum plants at high efficiency. Significant increases...

  1. Adventitious shoot regeneration from the leaves of in vitro grown 'Zhongli 1' pear (Pyrus spp.)

    Institute of Scientific and Technical Information of China (English)

    Jie LIU; Xi ZHANG; Bharat Kumar POUDYAL; Yuxing ZHANG; Zhan JIAO; Jing QI

    2009-01-01

    The pear (Pyrus spp.) is one of the most important temperate fruit crops. The technique of adven-titious shoot regeneration from leaves is considered to be one of the shortcuts in the research on pear genetic modification and cellular engineering, which, however, has not been widely used. As the regeneration frequency of pear leaves is usually very low, the research on adventi-tious shoot regeneration from pear leaves is eagerly needed. In this experiment, the factors affecting shoot and bud regeneration from the leaves of 'Zhongli 1' pear were studied, and an efficient protocol for shoot regenera-tion was established. The results showed that different types of basic media, different combinations of plant growth regulators, leaf placement on medium, periods of dark culture and the use of silver nitrate (AgNO3) on culture media all significantly affected the adventitious shoot regeneration frequency of 'Zhongli 1' pear. The details are as follows: (1) Among three kinds of basic media, NN69 was better for 'Zhongli 1' shoot regenera- tion, followed by half(1/2) MS, while full MS had no effect on shoot regeneration; (2) Thidiazuron (TDZ) was better than 6-benzylaminopurine (6-BA) for 'Zhongli 1' regen-eration, with an optimal concentration of 1.5 mg.L-1, and the regeneration rate under this concentration could reach 85%, with 2.72 buds per leaf. 0.5 mg .L-1 indole-3-butyric acid (IBA), which induced a higher regeneration fre-quency, was a better choice for pear regeneration compared with 0.3 mg.L-1 naphthaleneacetic acid (NAA). Among the different combinations of plant growth regulators, TDZ + IBA was better for inducing high regeneration frequency; (3) The abaxial surface of leaves touching the medium was beneficial for leaves to uptake nutrients from the medium, and because of that, the regeneration fre-quency of leaves was significantly higher than that of leaves touching the medium with their adaxial surfaces (obverse side of leaf); (4) Dark culture was necessary

  2. Permeabilization of plant tissues by monopolar pulsed electric fields: effect of frequency.

    Science.gov (United States)

    Asavasanti, Suvaluk; Ristenpart, William; Stroeve, Pieter; Barrett, Diane M

    2011-01-01

    Pulsed electric fields (PEF) nonthermally induce cell membrane permeabilization and thereby improve dehydration and extraction efficiencies in food plant materials. Effects of electrical field strength and number of pulses on plant tissue integrity have been studied extensively. Two previous studies on the effect of pulse frequency, however, did not provide a clear view: one study suggested no effect of frequency, while the other found a greater impact on tissue integrity at lower frequency. This study establishes the effect of pulse frequency on integrity of onion tissues. Changes in electrical characteristics, ion leakage, texture parameters, and percent weight loss were quantified for a wide range of pulse frequencies under conditions of fixed field strength and pulse number. Optical microscopy and viable-cell staining provided direct visualization of effects on individual cells. The key finding is that lower frequencies (f plant tissue. We hypothesize that cytoplasmic streaming plays a significant role in moving conductive ionic species from permeabilized cells to the intercellular space between plant cells, making subsequent pulses more efficacious at sufficiently low frequencies. The results suggest that decreasing the pulse frequency in PEF may minimize the number of pulses needed to achieve a desired amount of permeabilization, thus lowering the total energy consumption. Practical Application: PEF cause pores to be formed in plant cell membranes, thereby improve moisture removal and potential extraction of desirable components. This study used in situ microscopic evaluation of onion cells, as they were pulsed with electric fields at different frequencies, to determine whether frequency was an important parameter. We illustrate that membranes were more effectively broken at lower frequencies as compared to higher frequencies. Application of this information will allow for improved design of PEF systems for more energy efficient dehydration or extraction of

  3. Coordinated Fast Primary Frequency Control from Offshore Wind Power Plants in MTDC System

    DEFF Research Database (Denmark)

    Sakamuri, Jayachandra N.; Hansen, Anca Daniela; Cutululis, Nicolaos Antonio

    2016-01-01

    In this paper, coordinated fast primary frequency control (FPFC) from offshore wind power plants (OWPPs) integrated to surrounding onshore AC power system through a three terminal VSC HVDC system is presented. The onshore AC grid frequency variations are emulated at offshore AC grid through...... and the dynamics of wind turbine are also discussed. The corresponding impact of OWPPs active power output variation at different wind speeds on the power system frequency control and DC grid voltage is also presented. The results show that the proposed coordinated fast primary frequency control from OWPPs...... improves the power system frequency while relieving the stress on the other AC grid participating in frequency control....

  4. Plant regeneration of grapevine (Vitis sp.) protoplasts isolated from embryogenic tissue.

    Science.gov (United States)

    Reustle, G; Harst, M; Alleweldt, G

    1995-12-01

    Protoplasts with high embryogenic competence could be isolated from leaf-disk-derived embryos and embryoids of Vitis sp. cv. Seyval blanc. After a 4-week induction treatment in NN-69 medium supplemented with 4.0mg/l naphthoxyacetic acid (NOA) and 0.9mg/l thidiazuron (TDZ) and subsequent subcultivation in hormone-free medium, 38.5% of the developed microcalluses showed somatic embryogenesis. In contrast, only few formed somatic embryos after induction in CPW-13 medium with either 1.0mg/l 2,4-dichlorophenoxyacetic acid and 0.5mg/l benzylaminopurine treatment (13.8%) or NOA/TDZ treatment (1.4%). Up to 30% of these embryos germinated and about half of them regenerated into typical in vitro grapevines when transferred onto LS-medium in culture tubes.

  5. Effects of N(6)-benzylaminopurine and Indole Acetic Acid on In Vitro Shoot Multiplication, Nodule-like Meristem Proliferation and Plant Regeneration of Malaysian Bananas (Musa spp.).

    Science.gov (United States)

    Sipen, Philip; Davey, Michael R

    2012-12-01

    Different concentrations of N(6)-benzylaminopurine (BAP) and indole acetic acid (IAA) in Murashige and Skoog based medium were assessed for their effects on shoot multiplication, nodule-like meristem proliferation and plant regeneration of the Malaysian banana cultivars Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak. BAP at 1-14 mg L(-1) with or without 0.2 mg L(-1) IAA, or BAP at 7-14 mg L(-1) with the same concentration of IAA, was evaluated for shoot multiplication from shoot tips and the proliferation of nodule-like meristems from scalps, respectively. Plant regeneration from scalps was assessed using 1 mg L(-1) BAP and 0.2 mg L(-1) IAA separately, or a combination of these two growth regulators. Data on shoot multiplication, the proliferation of nodule-like meristems with associated plant regeneration were recorded after 30 days of culture. A maximum of 5 shoots per original shoot tip was achieved on medium supplemented with BAP at 5 mg L(-1) (Pisang Nangka), 6 mg L(-1) (Pisang Mas and Pisang Berangan), or 7 mg L(-1) (Pisang Awak), with 0.2 mg L(-1) IAA. BAP at 11 mg L(-1) with 0.2 mg L(-1) IAA induced the most highly proliferating nodule-like meristems in the four banana cultivars. Plant regeneration from scalps was optimum in all cases on medium containing 1 mg L(-1) BAP and 0.2 mg L(-1) IAA. This is the first report on the successful induction of highly proliferating nodule-like meristems and plant regeneration from scalps of the Malaysian banana cultivars Pisang Mas, Pisang Nangka, Pisang Berangan and Pisang Awak.

  6. Dynamics of male meiotic recombination frequency during plant development using Fluorescent Tagged Lines in Arabidopsis thaliana.

    Science.gov (United States)

    Li, Fan; De Storme, Nico; Geelen, Danny

    2017-02-13

    Meiotic homologous recombination plays a central role in creating genetic variability, making it an essential biological process relevant to evolution and crop breeding. In this study, we used pollen-specific fluorescent tagged lines (FTLs) to measure male meiotic recombination frequency during the development of Arabidopsis thaliana. Interestingly, a subset of pollen grains consistently shows loss of fluorescence expression in tested lines. Using nine independent FTL intervals, the spatio-temporal dynamics of male recombination frequency was assessed during plant development, considering both shoot type and plant age as independent parameters. In most genomic intervals assayed, male meiotic recombination frequency is highly consistent during plant development, showing no significant change between different shoot types and during plant aging. However, in some genomic regions, such as I1a and I5a, a small but significant effect of either developmental position or plant age were observed, indicating that the meiotic CO frequency in those intervals varies during plant development. Furthermore, from an overall view of all nine genomic intervals assayed, both primary and tertiary shoots show a similar dynamics of increasing recombination frequency during development, while secondary and lateral shoots remain highly stable. Our results provide new insights in the dynamics of male meiotic recombination frequency during plant development.

  7. Regeneration of Pea (’Pisum sativum L’.) Plants from Shoot Apical Meristems,

    Science.gov (United States)

    A procedure has been developed to obtain complete plants from meristems of three cultivars of Pisum sativum L. Benzyladenine (BA) alone or in...combination with naphthaleneacetic acid (NAA) at molar concentrations of 5 x .0000005 and .000001 respectively, induced shoot differentiation in meristems ...complete plant formation. Root formation, on the shoots produced by culturing meristems was induced by reculturing the shoots, 2 cm long, on half strength B5 medium supplemented with NAA at a concentration of .000001 M.

  8. Effects of Boreal Well Site Reclamation Practices on Long-Term Planted Spruce and Deciduous Tree Regeneration

    Directory of Open Access Journals (Sweden)

    Laurie A. Frerichs

    2017-06-01

    Full Text Available Well site development associated with oil sands exploration is common in boreal mixedwood forests of northern Alberta, Canada, and necessitates reforestation to accommodate other land uses. Little is known about the impact of soil and debris handling strategies during well site construction on long-term forest regeneration. This study addresses the impact of soil disturbance intensity, debris treatment, soil storage, and planting on the reforestation of 33 well sites reclaimed prior to 2006. Data on the survival and growth of planted white spruce (Picea glauca (Moench Voss and the regeneration density of deciduous trees, including trembling aspen (Populus tremuloides Michx, are presented from 2014 to 2015. The survival of planted spruce increased from 81% to 88% at well sites with a high relative to low soil disturbance. The total tree densities were lower in most treatments (≤2.69 stems m−2 than those in clear cuts (5.17 stems m−2, with the exception of root salvage areas where clear cuts had greater balsam poplar (Populus balsamifera L. densities (2.05 stems m−2 vs. <0.71 stems m−2 on all other treatments. Aspen densities were up to five times greater at well sites with low disturbance when compared to those with high disturbance, and this was further aided by shallow mulch at low disturbance sites. Spruce growth did not respond to well site treatments. Aspen growth (diameter and height remained similar between well site disturbance regimes; aspen exposed to high disturbance underperformed relative to low disturbance well sites and clear cut controls. With high disturbance, progressive soil piling led to increases in the density of aspen and birch (Betula papyrifera Marshall. Few long-term changes in soil were found due to well site development, with a greater soil pH in high disturbance sites compared to low disturbance sites. Overall, these results indicate that the nature of well site construction, including the extent of soil

  9. In vitro study on regeneration of Gladiolus grandiflorus corm calli as affected by plant growth regulators.

    Science.gov (United States)

    Torabi-Giglou, Mousa; Hajieghrari, Behzad

    2008-04-15

    In this study, in vitro organogenesis of Gladiolus grandiflorus cultivar pink corm segments were evaluated by culturing corm calli in modified MS medium supplemented with 3% sucrose and 0.7% agar with different concentration of BAP (0, 1, 2 and 4 mg L(-1) medium) and NAA (0, 0.5, 1 and 2 mg L(-1) medium) in factorial experiment of Completely Randomized Design (CRD). In order to obtain Gladiolus calli, corm segments (Aprox. 5 x 5 x 1 mm in size) were kept in modified MS medium (Murashige and Skoog, 1962) that was supplemented with 1 mg L(-1) 2, 4-D, 3% sucrose and 0.7% agar. The results showed that increasing the concentration of BAP from 0 to 2 mg L(-1) medium simulated plantlet regeneration but no significantly effect was obtained on shoot and cormel organogenesis between 2 and 4 mg L(-1) BAP concentration in medium. Increasing of NAA content in media without BAP developed rootlet significantly. Interaction results showed that increasing BAP content against decreasing of NAA concentration stimulates the shoot and cormel proliferation.

  10. Effect of colchicine applied to callus of mangosteen on morphological changes of regenerated plants

    Directory of Open Access Journals (Sweden)

    Te-chato, S.

    2000-07-01

    Full Text Available Calli of mangosteen raised on callus induction medium (CIM at 20 days of culture were submerged in various concentrations of colchicine. The cultures were incubated on a rotary shaker and shaken at 80 rpm for 2 hours. In the case of high concentrations of colchicine (500 and 750 mg/l, the calli were cultured directily on the colchicine-containing media for 90 days. The results showed that leaves of regenerated shoots contained more chlorophyll b than those of control. However, shoot size, leaf area and leaf number tended to decrease while number and lenght of roots increased. A high concentration of colchicine, 500 mg/l, produced shoots with brown-callused leaves. However, roots could be induced from these shoots to from complete plantlets. Some of the intact leaves produced a large number of shoots. Colchicine at 750 mg/l gave some morphological abnormalities with 5 roots per shoot. A small shoot could produce a large healthy root. Some shoots produced 3 leaves per whorl.

  11. Analysis of plants regenerated from protoplast fusions between Brassica napus and Eruca sativa.

    Science.gov (United States)

    Fahleson, J; Råhlén, L; Glimelius, K

    1988-10-01

    Protoplasts from etiolated hypocotyls of Brassica napus stained with carboxyfluorescein were fused with mesophyll protoplasts from Eruca sativa. Hybrid cells could be identified under the light microscope by (1) fully developed chloroplasts derived from E. sativa and (2) the cytoplasmic strands of the B. napus hypocotyl protoplasts, or (3) by the presence of both red and green fluorescence when investigated under UV light. The heterokaryons were selected using either a micro-manipulator or a flow sorter. On average, 5.4% of the calli obtained after selection differentiated into shoots. Regenerated shoots were subjected to isozyme analysis for verification of their hybrid character. Of the 23 hybrids successfully transferred to the greenhouse, 11 were asymmetric according to isozyme analysis. The nuclear DNA content of the hybrids was determined by flow cytometry, which gives an estimate of chromosome number. Most of the hybrids had a DNA content, and thus a chromosome number, that deviated from the expected sum of the parents. Almost all of the hybrids had some degree of fertility and produced seeds. Seed set, expressed as seeds per pollinated flower, was on average 7% of that of B. napus in the case of self-pollination and 26% of that of B. napus when backcrossed to B. napus. The chloroplast genotype was investigated in 13 hybrids. Of these, 11 had chloroplasts derived from B. napus, while only 2 had chloroplasts of E. sativa origin.

  12. Tissue culture-induced DNA methylation polymorphisms in repetitive DNA of tomato calli and regenerated plants

    NARCIS (Netherlands)

    Smulders, M.J.M.; Rus-Kortekaas, W.; Vosman, B.

    1995-01-01

    The propagation of plants through tissue culture can induce a variety of genetic and epigenetic changes. Variation in DNA methylation has been proposed as a mechanism that may explain at least a part of these changes. In the present study, the methylation of tomato callus DNA was compared with that

  13. High-efficiency Agrobacterium-mediated transformation of chickpea (Cicer arietinum L.) and regeneration of insect-resistant transgenic plants.

    Science.gov (United States)

    Mehrotra, Meenakshi; Sanyal, Indraneel; Amla, D V

    2011-09-01

    To develop an efficient genetic transformation system of chickpea (Cicer arietinum L.), callus derived from mature embryonic axes of variety P-362 was transformed with Agrobacterium tumefaciens strain LBA4404 harboring p35SGUS-INT plasmid containing the uidA gene encoding β-glucuronidase (GUS) and the nptII gene for kanamycin selection. Various factors affecting transformation efficiency were optimized; as Agrobacterium suspension at OD(600) 0.3 with 48 h of co-cultivation period at 20°C was found optimal for transforming 10-day-old MEA-derived callus. Inclusion of 200 μM acetosyringone, sonication for 4 s with vacuum infiltration for 6 min improved the number of GUS foci per responding explant from 1.0 to 38.6, as determined by histochemical GUS assay. For introducing the insect-resistant trait into chickpea, binary vector pRD400-cry1Ac was also transformed under optimized conditions and 18 T(0) transgenic plants were generated, representing 3.6% transformation frequency. T(0) transgenic plants reflected Mendelian inheritance pattern of transgene segregation in T(1) progeny. PCR, RT-PCR, and Southern hybridization analysis of T(0) and T(1) transgenic plants confirmed stable integration of transgenes into the chickpea genome. The expression level of Bt-Cry protein in T(0) and T(1) transgenic chickpea plants was achieved maximum up to 116 ng mg(-1) of soluble protein, which efficiently causes 100% mortality to second instar larvae of Helicoverpa armigera as analyzed by an insect mortality bioassay. Our results demonstrate an efficient and rapid transformation system of chickpea for producing non-chimeric transgenic plants with high frequency. These findings will certainly accelerate the development of chickpea plants with novel traits.

  14. C/sub 4/ photosynthesis in Euphorbia degeneri and E. remyi: a comparison of photosynthetic carbon metabolism in leaves, callus cultures and regenerated plants

    Energy Technology Data Exchange (ETDEWEB)

    Ruzin, S.E.

    1984-04-01

    Based on analysis of /sup 14/CO/sub 2/ fixation kinetics and assays of enzymes related to C/sub 4/ metabolism (NAD-ME, NADP-ME, NAD-MDH, NADP-MDH, AST, ALT), leaves and regenerated plants of Euphorbia degeneri exhibit a modified NADP-ME-type photosynthesis. Apparently, both aspartate and malate are used for transport of CO/sub 2/ to bundle sheath cells. Callus grown on either non-shoot-forming or shoot-forming media fixes CO/sub 2/ into RPP-cycle intermediates and sucrose, as well as malate and aspartate. /sup 14/CO/sub 2/ pulse/chase kinetics show no significant loss of label from C/sub 4/ acids throughout a one minute chase. Analysis of PEPCase revealed the presence of 2 isoenzymes in both leaf and regenerated plant tissues (K/sub m/ (PEP) = 0.080 and 0.550) but only one isoenzyme in callus (K/sub m/ = 0.100). It appears that C/sub 4/ photosynthesis does not occur in callus derived from this C/sub 4/ dicot but is regenerated concomitant with shoot regeneration, and ..beta..-carboxylation of PEP in callus, mediated by the low K/sub m/ isoenzyme of PEPCase, produces C/sub 4/ acids that are not involved in the CO/sub 2/ shuttle mechanism characteristic of C/sub 4/ photosynthesis. 161 references, 19 figures, 12 tables.

  15. Indirect regeneration from in vitro leaf tissue of periwinkle (Catharanthus roseus L. in response to different treatments of plant growth regulators

    Directory of Open Access Journals (Sweden)

    B.E. Sayed-Tabatabaei

    2012-03-01

    Full Text Available Periwinkle (Catharanthus roseus L. belongs to the Apocynaceae family and accumulates more than 130 terpenoid indole alkaloids (TIAs, of which two dimeric alkaloids Vinblastine and Vincristine have antineoplastic activity and are useful for treatment of various cancers. Therefore, the production of these drugs has been emphasized in plant tissue culture. In this research, 25 treatments of plant growth regulators to produce callus from leaf explants and seven treatments for regeneration of calli were considered. Analysis of variance showed that the effect of different hormonal treatments in the production of callus from leaf explants is significant (P<0.01. Application of 0.1 mg/L BAP and 5 mg/L NAA in nutrient media produced a lot of calli and roots. In addition, nutrient media containing activated charcoal and without it were found to be suitable for production of callus and regeneration, respectively. In conclusion, the results showed that indirect regeneration of leaf explants is not a suitable method for micropropagation of periwinkle due to difficult regeneration of callus, probability of mutation and lower number of produced branches. But this method can be utilized for production of secondary metabolites.

  16. 催眠睡茄植株再生体系的建立%Plant regeneration of Withania somnifera

    Institute of Scientific and Technical Information of China (English)

    罗正伟; 孙一铭; 吕翠萍; 王凤英; 孙际薇; 孙敏

    2012-01-01

    目的:建立和优化催眠睡茄植株再生体系.方法:以催眠睡茄的叶片作为外植体,探讨不同植物生长物质对愈伤组织诱导,丛生芽分化以及试管苗生根的影响.结果和结论:愈伤组织诱导的最佳培养基是MS+1.0mmg·L-12,4-D +0.1mg·L-1 KT;丛生芽诱导的最优培养基是MS +1.0mg·L-1 6-BA +0.1 nmg·L-1NAA,试管苗生根诱导最优培养基为1/2MS +0.5 mg·L-1NAA;在珍珠岩-腐殖土(1∶1)的基质中,再生植株室外移栽成活率达到92%.%Objective: To study tissue culture and plant regeneration of Withania somnifera. Method: Leaves of W, somnifera were used for explains, effects of different plant growth substances on callus and shoot induction were studied, different medium and plant growth substances for rooting induction was optimized. Result and Conclusion: The best plant growth substances combination for callus induction was MS + 1.0 mg·L-10 2,4-D +0.1 mg·L-1 KT. The optimal medium for germination was MS + 1.0 mg ·L-1 6-BA +0. 1 mg·L-1 NAA. The beet medium and plant growth substances combination for rooting induction was 1/2MS +0.5 mg· L-1 NAA, transplant survival rate of plantlet reached 92% in humus soil-pearlite(l:1).

  17. The Effect of Plant Growth Regulators on Callus Induction and Regeneration of Amygdalus communis

    Directory of Open Access Journals (Sweden)

    Naimeh SHARIFMOGHADAM

    2011-08-01

    Full Text Available The Almond (Amygdalus communis is one of the most important and oldest commercial nut crops, belonging to the Rosaceae family. Almond has been used as base material in pharmaceutical, cosmetic, hygienically and food industry. Propagation by tissue culture technique is the most important one in woody plants. In the current research, in vitro optimization of tissue culture and mass production of almond was investigated. In this idea, explants of actively growing shoots were collected and sterilized, then transferred to MS medium with different concentrations and combinations of plant growth regulators. The experiment was done in completely randomized blocks design, with 7 treatment and 30 replications. After 4 weeks, calli induction, proliferation, shoot length and number of shoot per explants were measured. Results showed that the best medium for shoot initiation and proliferation was MS + 0.5 mg/l IAA (Indol-3-Acetic Acid + 1 mg/l BA (Benzyl Adenine. Autumn was the best season for collecting explants. The shoots were transferred to root induction medium with different concentrations of plant growth regulators. The best root induction medium was MS + 0.5 mg/l IBA (Indol Butyric Acid.

  18. Genetic stability and phytochemical analysis of the in vitro regenerated plants of Dendrobium nobile Lindl., an endangered medicinal orchid

    National Research Council Canada - National Science Library

    Bhattacharyya, Paromik; Kumaria, Suman; Diengdoh, Reemavareen; Tandon, Pramod

    2014-01-01

    An efficient genetically stable regeneration protocol with increased phytochemical production has been established for Dendrobium nobile, a highly prized orchid for its economic and medicinal importance...

  19. Somatic Embryogenesis Induction and Plant Regeneration in Strawberry Tree (Arbutus unedo L.).

    Science.gov (United States)

    Martins, João F; Correia, Sandra I; Canhoto, Jorge M

    2016-01-01

    Somatic embryogenesis is a powerful tool both for cloning and studies of genetic transformation and embryo development. Most protocols for somatic embryogenesis induction start from zygotic embryos or embryonic-derived tissues which do not allow the propagation of elite trees. In the present study, a reliable protocol for somatic embryogenesis induction from adult trees of strawberry tree is described. Leaves from in vitro proliferating shoots were used to induce somatic embryo formation on a medium containing an auxin and a cytokinin. Somatic embryos germinated in a plant growth regulator-free medium.

  20. Plant regeneration from excised bulb scale segments of Zephyranthes robusta Baker

    Directory of Open Access Journals (Sweden)

    Mirosława Furmanowa

    2014-01-01

    Full Text Available Zephyranthes robusta Baker excised bulb scale segments with the basal plate were grown on Murashige and Skoog (MS medium in four modifications. The cultures were kept at 25°C in darkness. The best results (bulbing, leaf development and rooting were obtained on MS medium with 1 mg/l IBA, 2-6 bulblets being developed from one explant. After 6 weeks the plantlets (4-6 cm high were transferred to pots filled with sterilized soil mixes. After two months the leaves of the plants reached a length of 20 cm.

  1. Plant regeneration in vitro of South Pacific taro (Colocasia esculenta var. esculenta cv. Akalomamale, Aracea).

    Science.gov (United States)

    Yam, T W; Hsu, G I; Arditti, J

    1990-08-01

    Axillary bud expiants from South Pacific (Solomon Islands) taro, Colocasia esculenta var. esculenta cv. Akalomamale (Araceae) cultured on a modified Murashige-Skoog medium containing 1 mg NAA 1(-1) and TE formed callus and produced multiple plantlets. Explants died if NAA was present at levels lower than 0.1 mg 1(-1). BA was not required and may have been inhibitory. Plantlets developed faster and became larger following transfer to a hormone-free medium two weeks after the start of culture. Fully grown plants were established in a potting mix and are growing well in a greenhouse.

  2. Efficient procedure for grapevine embryogenic suspension establishment and plant regeneration: role of conditioned medium for cell proliferation.

    Science.gov (United States)

    Ben Amar, A; Cobanov, P; Boonrod, K; Krczal, G; Bouzid, S; Ghorbel, A; Reustle, G M

    2007-09-01

    An efficient system for the establishment and multiplication of highly prolific embryogenic cell cultures of grapevine (Vitis sp.) was developed. Using anther-derived pro-embryogenic masses as starting material, cell suspensions of different grapevine cultivars (Tempranillo, Cabernet-Sauvignon) and rootstocks (Kober 125 AA, Kober 5 BB, 110 Richter) were initiated in liquid medium containing NOA (1.0 mg l(-1)) and BAP (0.25 mg l(-1)) as growth regulators. Conditioned medium was recovered and utilised for establishing new, highly totipotent cell cultures. The suspensions obtained, showed embryogenic competence resulting in somatic embryo induction and subsequent plant regeneration. In this study, a simplified establishment procedure for grapevine embryogenic cell suspension allowing the fast multiplication of embryogenic material is described. Evidence for the promoting effect of the protein fraction derived from conditioned medium, on cell proliferation was found. In bioassays, addition of ss-D: -GlcY affect cell proliferation suggesting that arabinogalactan proteins are required for growth processes in grapevine cell cultures.

  3. Effect of different plant growth regulators on micro-tuber induction and plant regeneration of Pinellia ternate (Thunb) Briet.

    Science.gov (United States)

    Wang, Junli; Wang, Qian; Wang, Jue; Lu, Yuan; Xiao, Xuan; Gong, Weizhen; Liu, Jikai

    2009-10-01

    An efficient micropropagation system for Pinellia ternate (Thunb) Briet, a traditional Chinese medicinal plant, has been developed. Petiole and lamina of P. ternate were used as explants and cultured on Murashige and Skoog (MS) medium containing different concentrations of different plant growth regulators. The results indicated that low concentration of 2,4-dicholorophenoxy acetic acid (2,4-D), indole-3-acetic acid (IAA) and α-naphthalene acetic acid (NAA) were suitable for micro-tuber induction, but callus induction rate increased with increasing concentrations of growth regulators. Tubers induction rates of petiole and leaf were (81.8 %-100 %) and (89.4 %-96.0 %) respectively, when 0.2 mg l(-1) 2, 4-dicholorophenoxy acetic acid, indole-3-acetic acid or α-naphthalene acetic acid were present in the medium. Tubers induction rates of petiole and leaf cultured on MS medium supplemented with 0.2-0.5 mg l(-1) 6-benzyl amino purine (6-BAP) were (94.1 %-100 %) and (96.0 %-100 %) respectively. When the concentration of 2,4-dicholorophenoxy acetic acid, α-naphthalene acetic acid and 6-benzyl amino purine was increased to 2.0 mg l(-1), callus induction rates of petiole and leaf were 100 % and 98.2 %, 91.0 % and 36.0 %, 62.3 % and 70.0 %, respectively. Different concentration of kinetin (KT) and zeatin (ZT) had no significant effect on micro-tuber induction of petiole. Most petioles showed polarity during the cultivation of explants, when supplemented with different concentrations of auxin or cytokinin in the MS medium.

  4. CALLUS INDUCTION AND PLANT REGENERATION IN PUNICA GRANATUM L. ?NANA' FROM LEAF EXPLANTS

    Directory of Open Access Journals (Sweden)

    Alireza Bonyanpour

    2013-09-01

    Full Text Available ABSTRACT In this investigation, leaf explants of a local cultivar of dwarf pomegranate were placed on Murashige and Skoog (1962 (MS medium supplemented with various concentrations of 6-benzyl adenin (BA and naphthalene acetic acid (NAA for callus induction. After 40 days, maximum callus induction was observed on a media containing 1 mg L-1 BA and 0.2 to 0.4 mg L-1 NAA. However, the highest callus growth was obtained on a medium containing 1 mg L-1 BA and 1 mg L-1 NAA. The highest number of shoots (7 shoots per explants was obtained by transferring the calli to the media containing 5 mg L-1 BA with 0.1 mg L-1 NAA. Maximum shoot proliferation was observed when shoots were cultured on woody plant medium (WPM supplemented with 5 mg L-1 kinetin (Kin. In this treatment, after 4 subcultures, 36 shoots were produced from one original explant. Among treatments used in rooting experiments, shoots cultured on WPM medium containing 0.2 mg L-1 indol butyric acid (IBA had the maximum root percentage (100% and good root growth (2.06 cm mean length and 2 roots in each explants. Rooted plantlets were cultured in a soil mixture containing vermiculite (60%, perlite (30% and coco peat (10% v/v. After 2 months, 80% of plants survived and transferred to the greenhouse.

  5. Plant regeneration from seeds responds to phylogenetic relatedness and local adaptation in Mediterranean Romulea (Iridaceae) species.

    Science.gov (United States)

    Carta, Angelino; Hanson, Sarah; Müller, Jonas V

    2016-06-01

    Seed germination is the most important transitional event between early stages in the life cycle of spermatophytes and understanding it is crucial to understand plant adaptation and evolution. However, so far seed germination of phylogenetically closely related species has been poorly investigated. To test the hypothises that phylogenetically related plant species have similar seed ecophysiological traits thereby reflecting certain habitat conditions as a result of local adaptation, we studied seed dormancy and germination in seven Mediterranean species in the genus Romulea (Iridaceae). Both the across-species model and the model accounting for shared evolutionary history showed that cool temperatures (≤ 15°C) were the main factor that promoted seed germination. The absence of embryo growth before radicle emergence is consistent with a prompt germination response at cool temperatures. The range of temperature conditions for germination became wider after a period of warm stratification, denoting a weak primary dormancy. Altogether these results indicate that the studied species exhibit a Mediterranean germination syndrome, but with species-specific germination requirements clustered in a way that follows the phylogenetic relatedness among those species. In addition, species with heavier seeds from humid habitats showed a wider range of conditions for germination at dispersal time than species from dry habitats possessing lighter seeds. We conclude that while phylogenetically related species showed very similar germination requirements, there are subtle ecologically meaningful differences, confirming the onset of adaptation to local ecological factors mediated by species relatedness.

  6. Plant regeneration via somatic embryogenesis from protoplast of Clausena harmandiana (Engl. Swing and M. Kell

    Directory of Open Access Journals (Sweden)

    Hasan Basri JUMIN

    2013-05-01

    Full Text Available Protoplasts isolated from embryogenic callus of Clausena harmandiana (Engl. 'Swing. and M. Kell. were cultured in MT (Murashige and Tucker 1969 basal medium containing 5% sucrose supplemented with bezyladenine (BA, malt extract (ME and 0.6 M sorbitol. The highest plating efficiency was obtained on MT basal medium containing 5% sucrose supplemented with 0.01 mg 1-1 BA and 600 mg 1-1 ME, MT basal medium containing 5% sucrose and supplemented with 0.01 mg 1-1 6(-y,y-dimethylallylamino-purine was found to be a medium suitable for the development somatic embryos into heart-shaped somatic embryos. The highest percentage of shoot formation- was obtained using 0.1 mg 1-1 gibberellic acid (GA3 + 0.1 mg 1-1 zeatin. In this investigation 25 plants were survived and grew normally in the soil.

  7. Parameterised controller synthesis for SISO-LTI uncertain plants using frequency domain information

    Science.gov (United States)

    Parastvand, Hossein; Khosrowjerdi, Mohammad-Javad

    2016-01-01

    This paper extends the results of a new model-free approach which has been applied to guarantee nominal stability and performance. In this paper, using a particular controller structure, the robust stability (RS) and robust performance (RP) criteria for single input single output linear time invariant (SISO-LTI) plants with multiplicative uncertainty are transformed to affine functions in terms of controller parameters. It is shown that solving the feasibility problem of these new criteria will lead to controllers that guarantee the RS and performance. There is no need for a plant mathematical model. The required data for controller synthesis are just the frequency responses corresponding to limited samples of the uncertain plant. Also, there is no need for exact data at each frequency for the whole set of frequency responses. The approach is also applicable for designing both low- and high-order controllers. The effectiveness of the proposed technique is illustrated by simulation results.

  8. 花曲柳茎芽增殖和植株再生%Shoot multiplication and plant regeneration in Fraxinus rhynchophylla Hance

    Institute of Scientific and Technical Information of China (English)

    单琳; 杨玲; 沈海龙

    2011-01-01

    In order to establish a high frequency system of tissue culture and plant regeneration in Fraxinus rhynchophylla, taking adventitious stem segments with buds induced from dormant bud and seedling in F. Rhynchophylla as explants, the optimal nutrient media and different combinations of plant growth regulators were selected out, multiple shoots were induced and regenerated plants were obtained. The results showed that April was superior to other periods for collecting dormant buds. The proliferation coefficient of shoots from dormant bud was 2.32 in improved B5 medium supplemented with 4 mg · L-1 BA and 0.10 mg · L-1 IBA, and the proliferation coefficient of shoots from aseptic seedling in the same medium was over 3.0, so the medium was optimal. Rooting rate of shoot could reach 95% in 1/2MS medium supplemented with 0.5 mg · L-1' NAA, so it was optimal medium for rooting. Survival rate of the established plantlets could reach 92% after transferring to growing medium with composition of 50% peat moss, 40% vermiculite and 10% polite. Shoot could root after quickly dipping in 200 g · L"' IBA, and survival rate could reach 60% in the same medium.%为建立高效的花曲柳组培快繁体系,以花曲柳休眠芽萌发获得的带芽茎段和成熟种子无菌萌发获得的带芽茎段为外植体,通过基本培养基和不同植物生长调节剂组合的筛选,诱导出丛生芽,获得了再生植株.结果表明:花曲柳休眠芽采集的最适时期是4月中旬,适合的基本培养基为改良的B5培养基,在改良的B5培养基上添加BA 4.0 mg·L-1和IBA 0.10 mg·L-1,茎芽可以实现增殖,增殖系数可达2.3;在相同培养基上,无菌苗茎段的茎芽增殖系数可达3.0以上;最适的试管内生根培养基为添加NAA 0.5 mg·L-1的1/2MS培养基,茎芽的生根率可达95%,再生植株在草炭土、蛭石和珍珠岩体积比5:4:1的栽培基质中移栽成活率为92%.茎芽速蘸IBA 200 g·L-1后在上述栽培基质中试管

  9. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis Regeneração de plantas a partir de protoplastos de alfafa (Medicago sativa) via embriogênese somática

    OpenAIRE

    Mariza Monteiro; Beatriz Appezzato-da-Glória; Maria José Valarini; Carlos Alberto de Oliveira; Maria Lucia Carneiro Vieira

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  10. [Molecular-genetic polymorphism of cellular lines of wheat resistant to cultural filtrate Gaeumannomyces graminis var. tritici and plant-regenerants from them].

    Science.gov (United States)

    Bavol, A V; Dubrovna, O V

    2009-01-01

    DNA polymorphism of wheat cellular lines resistant to culture filtrate of G. graminis var. tritici and regenerated plants has been investigated using ISSR-analysis. Specific changes in DNA sequence were revealed in resistant calluses. It was established, that all resistant cellular lines differed by the presence of specific amplicons of 2347 bp (primer 5'-TCTCTCTCTCTCTCTCG-3') and 1745 bp (primer 5'-AGAGAGAGAGAGAGAGTC-3'), as well as the absence of the amplicon of 1108 bp (primer 5'-ACACACACACACACACC-3') from the initial callus and the callus not exposed to the action of selective factor. These changes have been also revealed in R0 and R1 plants.

  11. Plant Regeneration of Ziziphus spina-christi by in vivo and in vitro Methods

    Institute of Scientific and Technical Information of China (English)

    M.H.ASSAREH; H.SARDABI; F.SABBAGHZADEH

    2005-01-01

    Christ's thorn (Ziziphus spina-christi L. Desf.) is ecologically and economically important in Iran. Since it is a crosspollinated plant with a wide range of genetic variability, an investigation was carried out to determine the best method for mass and clonal propagation. Three vegetative methods were examined, including 1) cutting, where shoots with a 22-25 cm length and three shoot diameters were treated with two culture media; 2) layering, where air layering and trench layering treatments consisted of three growth regulators at three levels of concentration; and 3) tissue culture with nodal segments bearing axillary buds that were removed from shoots of mature trees at different seasons. Several experiments were carried out to determine the best disinfectant chemical, the best culture method, the best season, the appropriate explant characteristics and media type. Rooting was successful only on the sandy beds for cuttings with more than 8.0 mm diameter. For the trench layering method, only one specimen in one replicate rooted a very small root, while for the air layering method, only seedlings with growth regulator treatments rooted successfully. The best season for explant harvesting was determined as mid summer, and among the disinfecting treatments, Ca(OCl)2 at a concentration of 0.5 g kg-1 for 20 minutes was the best. There were no significant differences for shoot weight and length with a Murashige and Skoog (MS) medium with and without a hormone.

  12. Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.

    1996-11-01

    This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants.

  13. Agrobacterium-mediated genetic transformation and regeneration of transgenic plants using leaf midribs as explants in ramie [Boehmeria nivea (L.) Gaud].

    Science.gov (United States)

    An, Xia; Wang, Bo; Liu, Lijun; Jiang, Hui; Chen, Jie; Ye, Shengtuo; Chen, Leiyu; Guo, Pingan; Huang, Xing; Peng, Dingxiang

    2014-05-01

    In this study, leaf midribs, the elite explants, were used for the first time to develop an efficient regeneration and transformation protocol for ramie [Boehmeria nivea (L.) Gaud.] via Agrobacterium-mediated genetic transformation. Sensitivity of leaf midribs regeneration to kanamycin was evaluated, which showed that 40 mg l(-1) was the optimal concentration needed to create the necessary selection pressure. Factors affecting the ramie transformation efficiency were evaluated, including leaf age, Agrobacterium concentration, length of infection time for the Agrobacterium solution, acetosyringone concentration in the co-cultivation medium, and the co-cultivation period. The midrib explants from 40-day-old in vitro shoots, an Agrobacterium concentration at OD600 of 0.6, 10-min immersion in the bacteria solution, an acetosyringone concentration of 50 mg l(-1) in the co-cultivation medium and a 3-day co-cultivation period produced the highest efficiencies of regeneration and transformation. In this study, the average transformation rate was 23.25%. Polymerase chain reactions using GUS and NPTII gene-specific primers, Southern blot and histochemical GUS staining analyses further confirmed that the transgene was integrated into the ramie genome and expressed in the transgenic ramie. The establishment of this system of Agrobacterium-mediated genetic transformation and regeneration of transgenic plants will be used not only to introduce genes of interest into the ramie genome for the purpose of trait improvement, but also as a common means of testing gene function by enhancing or inhibiting the expression of target genes.

  14. Efficient plant regeneration protocol through callus for Saussurea obvallata (DC.) Edgew. (Asteraceae): effect of explant type, age and plant growth regulators.

    Science.gov (United States)

    Dhar, Uppeandra; Joshi, Mitali

    2005-06-01

    A callus induction and in vitro plantlet regeneration system for the endangered state flower of Uttaranchal (Saussurea obvallata) was optimized by studying the influence of explant type (root, hypocotyl, cotyledon and leaf), age and different concentrations of plant growth regulators. Explants from 10 to 15-day-old seedlings showed maximum callus induction. Callus formation and shoot differentiation was initiated on Murashige-Skoog (MS) medium containing 6-benzyladenine (BA) and alpha-naphthalene acetic acid (NAA) in all explant types. The best results were obtained using leaf explants: 100% callusing was achieved in MS medium supplemented with 2.5 microM BA and 1.0 microM NAA, and 100% differentiation along with a multiplication rate of 12 shoots per explant with a combination of 5.0 microM BA and 1.0 microM NAA. However, the results reflected the existence of high inter-explant variability in response to growth regulators. In vitro rooting of shoots was achieved at an efficiency of 100% in one-half strength MS medium supplemented with 2.5 microM indole-3-butyric acid. Application of this protocol has potential for mass multiplication of the target species in a limited time period.

  15. Micronucleus frequency is increased in peripheral blood lymphocytes of nuclear power plant workers.

    Science.gov (United States)

    Hadjidekova, Valeria B; Bulanova, Minka; Bonassi, Stefano; Neri, Monica

    2003-12-01

    Nuclear power plant workers are exposed to ionizing radiation at relatively low doses and for prolonged periods of time. To investigate the extent of genetic damage in these workers, a group of 133 nuclear power plant workers and 39 healthy controls were compared using the cytokinesis-block micronucleus assay. The frequency of micronuclei was significantly increased in peripheral lymphocytes of nuclear power plant workers (20.5 +/- 9.7% compared to 13.7 +/- 5.9%). A significant dose-response relationship was observed between micronucleus (MN) frequency and both the accumulated dose and the duration of employment (P < 0.01 for both variables after adjusting for age, gender and cigarette smoking) with an evident leveling off for exposures over 200 mSv. Accumulated dose and duration of employment were significantly correlated but exerted independent effects on MN frequency. For non-occupational parameters, age was significantly associated with the frequency of micronuclei, while gender was not. Smoking habit showed no overall effect, whereas increased chromosome damage was evident in smokers of more than 20 cigarettes per day. In conclusion, a dose-related association between MN frequency and exposure to ionizing radiation was evident in nuclear power plant workers, encouraging the application of the cytokinesis-block micronucleus assay in biomonitoring studies of human populations with prolonged exposure to ionizing radiation.

  16. Alternatives for Primary Frequency Control Contribution from Wind Power Plants Connected to VSC-HVDC Intertie

    DEFF Research Database (Denmark)

    Laukhamar, Andreas Grøsvik; Zeni, Lorenzo; Sørensen, Poul Ejnar

    how a large offshore wind power plant (OWPP) with high voltage direct current (HVDC) intertie connection to two asynchronous onshore AC power systems can be part of the solution in providing short-term mutual active power balancing. The primary frequency control is investigated for four different...... in a sharing of the primary reserves and rolling inertia between the two onshore AC power systems connected to the HVDC intertie, whilst also exploiting the OWPP in the primary frequency control scheme....

  17. Callus formation and plant regeneration from protoplasts of sunflower calli and hypocotyls

    Directory of Open Access Journals (Sweden)

    Conceição Santos

    2014-02-01

    Full Text Available Sunflower (cv. Girapac SH222 protoplasts were obtained from 4-7 day-old hypocotyls and cotyledons and from two-month old calli. Higher yields of protoplasts were achieved with medium El (KCl 25g dm-3, CaCl2 2g dm-3, MES 0.7 g• dm-3, pH 5.5 and the combination of Driselase Fluka 0.2%, Macerozyme Onozuka 0.2% and Cellulase Onozuka R10 0.2%. Hypocotyls gave the highest yields of protoplasts, followed by cotyledons and calli. Protoplasts were cultivated in liquid and on solid media using both L4M (Burrus et al., 1991 and V-KM (Bokelman and Roest, 1983 media. Culture on solid M1 medium (L4M medium supplemented with NAA 3.0 mg•dm- 3, 2,4-D 0.1 mg•dm-3 and BA 1.0 mg•dm -3 gave a good planting efficiency with the development of many white-green colonies. These colonies gave rise to small calli which were transferred to MSmod medium (MS medium supplemented with KCI 5 g•dm-', and polyvinylpyrrolidone (PVP, 4 g• dm-3 containing benziladenine (BA, 0.5 mg•dm-3, naphtaleneacetic acid (NAA, 0.5 mg•dm-3 and giberelic acid (GA3 0.1 mg•dm-3. After two weeks, calli were transferred to MSmod medium containing BA 1.0 mg•dm-3, NAA 0.1 mg•dm-3, and GA3 0.1 mg•dm-3 for shoot formation. Shoots were excised and induced to root in MSmod supplemented with BA 0.1 mg•dm-3, NAA 1.0 mg•dm-3, and GA3 0.1 mg•dm-3. Plantlets were then transferred to sterilised vermiculite for greenhouse acclimation.

  18. Enhanced electroporation in plant tissues via low frequency pulsed electric fields: influence of cytoplasmic streaming.

    Science.gov (United States)

    Asavasanti, Suvaluk; Stroeve, Pieter; Barrett, Diane M; Jernstedt, Judith A; Ristenpart, William D

    2012-01-01

    Pulsed electric fields (PEF) are known to be effective at permeabilizing plant tissues. Prior research has demonstrated that lower pulse frequencies induce higher rates of permeabilization, but the underlying reason for this response is unclear. Intriguingly, recent microscopic observations with onion tissues have also revealed a correlation between PEF frequency and the subsequent speed of intracellular convective motion, i.e., cytoplasmic streaming. In this paper, we investigate the effect of cytoplasmic streaming on the efficacy of plant tissue permeabilization via PEF. Onion tissue samples were treated with Cytochalasin B, a known inhibitor of cytoplasmic streaming, and changes in cellular integrity and viability were measured over a wide range of frequencies and field strengths. We find that at low frequencies (f streaming results in a 19% decrease in the conductivity disintegration index compared with control samples. Qualitatively, similar results were observed using a microscopic cell viability assay. The results suggest that at low frequencies convection plays a statistically significant role in distributing more conductive fluid throughout the tissue, making subsequent pulses more efficacious. The key practical implication is that PEF pretreatment at low frequency can increase the rate of tissue permeabilization in dehydration or extraction processes, and that the treatment will be most effective when cytoplasmic streaming is most active, i.e., with freshly prepared plant tissues.

  19. Effects of climate warming on plant autotoxicity in forest evolution: a case simulation analysis for Picea schrenkiana regeneration.

    Science.gov (United States)

    Ruan, Xiao; Pan, Cun-De; Liu, Run; Li, Zhao-Hui; Li, Shu-Ling; Jiang, De-An; Zhang, Jing-Chi; Wang, Geoff; Zhao, Yin-Xian; Wang, Qiang

    2016-08-01

    In order to explore how plant autotoxicity changes with climate warming, the autotoxicity of P. schrenkiana needles' water extract, organic extract fractions, and key allelochemical DHAP was systemically investigated at the temperature rising 2 and 4°C based on the data-monitored soil temperature during the last decade in the stage of Schrenk spruce regeneration (seed germination and seedling growth). The results showed that the criterion day and night temperatures were 12°C and 4°C for seed germination, and 14°C and 6°C for seedling growth, respectively. In the presence of water extract, the temperature rise of 2°C significantly inhibited the germination vigor and rate of P. Schrenkiana seed, and a temperature rise of 4°C significantly increased the inhibition to the seedling growth (P < 0.05). Among the three organic fractions, the low-polar fraction showed to be more phytotoxic than the other two fractions, causing significant inhibitory effects on the seed germination and growth even at low concentration of 0.1 mg/mL, and the inhibition effect was enhanced as temperature increased. The temperature rise significantly enhanced the promotion effect of DHAP, while the inhibition effect of temperature rise became less important with increasing concentration of DHAP. This investigation revealed that autotoxicity of P. schrenkiana was affected by the climate warming. As expected, it provided an insight into the mechanism and effectiveness of allelopathy in bridging the causal relationship between forest evolution and climate warming.

  20. 川芎高频再生体系的建立%Establishment and Optimization of High-frequency Shoot Regeneration System of Ligusticum chuanxiong Hort.

    Institute of Scientific and Technical Information of China (English)

    朱玲玲; 梅兰菊; 唐琳

    2012-01-01

    We explored optimized induction and differentiation medium and culture conditions to establish a protocol of rapid clonal propagation of Ligusticum chuanxiong Hort. The petioles were the best explant and Murashige and Skoog (MS) medium containing 2.0 mg/L KT and 0. 5 mg/L IAA was suitable for high-frequency shoot regeneration. The results suggested that callus were induced from petioles of aseptic seedlings in dark conditions. And then these callus were subcuttured for 15 days in light conditions,about 44.4% frequency of shoot regeneration was induced. The rooting percentage of the regenerated shoots reached 90% on 1/2 MS supplemented with 0.5 mg/L NAA and 0. 5 mg/L IBA. Approximately 95% rooted shoots survived in a greenhouse.%为建立川芎(Ligusticum chuanxiong Hort.)高频再生体系,优化了诱导和分化培养基及培养条件.以叶柄为外植体,以MS为基本培养基,KT2.0 mg/L+ IAA0.5mg/L的激素组合对不定芽分化最有利.在此基础上,针对外植体来源、培养条件和愈伤组织继代时间3个因素进行优化.结果表明:采用川芎无菌苗叶柄作为外植体,黑暗条件下诱导出愈伤组织,再在光照下继代培养15d后转入分化培养基中对不定芽诱导最为有利,分化率为44.4%.分化后得到的不定芽在含NAA0.5 mg/L和IBA 0.5 mg/L的1/2MS培养基上生根率达90%,移栽存活率为95%.

  1. Shoot organogenesis in leaf explants of Hydrangea macrophylla ‘Hyd1’ and assessing genetic stability of regenerants using ISSR markers

    NARCIS (Netherlands)

    Liu, F.; Huang, L.L.; Reinhoud, P.; Jongsma, M.A.; Wang, C.

    2011-01-01

    For the first time, an in vitro regeneration protocol of Hydrangea macrophylla 'Hyd1' was developed. Effects of different plant growth regulators (PGRs) on shoot regeneration were investigated jointly with selecting optimal basal media and cefotaxime concentrations. The highest frequency of shoot or

  2. Establishment of a Rapid Plant Regeneration System in Physalis angulata L. through Axillary Meristems

    Directory of Open Access Journals (Sweden)

    Owk ANIEL KUMAR

    2015-12-01

    Full Text Available An optimal plant propagation method of Physalis angulata L., a medicinally important herbaceous plant species has been developed using axillary meristem explants. Shoot bud proliferation was initiated from axillary meristem explants cultured on MS medium supplemented with various concentrations of 0.5-2.5mg/L/(BAP/(Zeatin/(KIN. The maximum in vitro response of shooting frequency of explants (88.1% and shoots per explant (42 was achieved with medium containing 1.0mg/L BAP. Multiple shoot culture was established by repeated subculturing of the shoot buds of axillary meristems on shoot multiplication medium. Among the subculture media BAP in combination with 1.5mg/L (IAA+0.25mg/L(GA3 produced maximum shoots per explant (128±0.29 after two weeks of culture. Effective in vitro shoot elongation and rooting was achieved on 1.0mg/L(GA3 and 1.0mg/L(IBA, respectively. Most of the generated shoots were successfully transferred to soil under field conditions. The survival percentage of the transferred plants on soil was found to be 90 per cent.  This protocol can be used for commercial propagation and for future genetic improvement studies.

  3. Determining generator parameters of Camargos hydroelectric power plant through frequency response measurement

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Sebastiao E.M. de; Padua Guarini, Antonio de [Centro de Pesquisas de Energia Eletrica (CEPEL), Rio de Janeiro, RJ (Brazil); Souza, Joao A. de; Valgas, Helio M.; Pinto, Roberto del Giudice R. [Companhia Energetica de Minas Gerais (CEMIG), Belo Horizonte, MG (Brazil)

    1994-12-31

    This work describes the results of the set frequency response tests performed in the generator number 2, 6.9 kV, 25 MVA, of Camargos hydroelectric power plant, CEMIG, and the parameters relatives to determined structures of model. This tests are unpublished in Brazil. (author) 7 refs., 16 figs., 7 tabs.

  4. Ancillary Frequency Control of Direct Drive Full-Scale Converter Based Wind Power Plants

    DEFF Research Database (Denmark)

    Hu, Weihao; Su, Chi; Fang, Jiakun;

    2013-01-01

    This paper presents a simulation model of a wind power plant based on a MW-level variable speed wind turbine with a full-scale back-to-back power converter developed in the simulation tool of DIgSILENT Power Factory. Three different kinds of ancillary frequency control strategies, namely inertia ...

  5. Light Requirement for Shoot Regeneration in Horseradish Hairy Roots 1

    Science.gov (United States)

    Saitou, Tsutomu; Kamada, Hiroshi; Harada, Hiroshi

    1992-01-01

    Hairy roots of horseradish (Armoracia rusticana) were induced by inoculation with Agrobacterium rhizogenes harboring Ri plasmid and cultured on phytohormone-free Murashige and Skoog medium after eliminating the bacteria. Hairy roots grew vigorously and sometimes formed yellowish calli under dark conditions. On the other hand, growth of hairy roots stopped after several weeks of culture with light, then shoots were regenerated. Frequency of shoot formation from hairy roots increased as the culture period in light lengthened and the light intensity increased. The shoot regeneration was induced by treatment with white or red light, but not with far-red light. Shoot regeneration by red light was inhibited by following treatment with far-red light. Red and far-red light reversibly affected shoot regeneration. Excised roots of nontransformed plants grew quite slowly on phytohormone-free Murashige and Skoog medium and occasionally formed shoots under white light conditions. PMID:16669041

  6. Uniform Design for Optimizating Regeneration Shoots Directly from Tender Leaves and Plant Regeneration System of Rhododendron chrysanthum Pall.%基于均匀设计优化牛皮杜鹃嫩叶直接再生芽苗及植株再生体系

    Institute of Scientific and Technical Information of China (English)

    李玉梅; 姜云天; 孙智慧

    2008-01-01

    [Objective] The experimental was aimed to screen the optimum regeneration shoot induction media and rooting media for tender leaves of Rhododendron chrysanthum Pall.[Method] The tender leaves of Rhododendron chrysanthum Pall were taken as explants to select the optimum bud induction media and rooting media through uniform design and the screening results were verified.[Result] The optimum media for regeneration shoot of Rhododendron chrysanthum Pall contained 1/4 MS,3.70 mg/L ZT, 0.02 mg/L IAA and 1.00 mg/L KT and its induction rate was 95.5% and the rooting media contained modified MS, 0.10 mg/L IAA and 0.07 mg/L NAA and its rooting rate was 98%. [Conclusion] Through this experiment, regeneration systems for regeneration shoot and regenerated plant from tender leaves of Rhododendron chrysanthum Pall were created successfully.

  7. [Genetic transformation of buckwheat ( Fagopyrum esculentum Moench ) with AtNHX1 gene and regeneration of salt-tolerant transgenic plants].

    Science.gov (United States)

    Cheng, Li-Hong; Zhang, Bo; Xu, Zi-Qin

    2007-01-01

    The Arabidopsis thaliana tonoplast Na+ /H+ antiporter gene, AtNHX1, was transferred into buckwheat by Agrobacterium-mediated method. Transgenic buckwheat plants were regenerated and selected on MS basal medium supplemented with 2.0mg/L 6-BA, 1.0mg/L KT, 0.lmg/L IAA, 50mg/L kanamycin and 500mg/L carbenicillin. 426 seedlings from 36 resistant calli originated from 864 explants (transformed about at 4.17 percentage) exhibited resistance to kanamycin. The transformants were confirmed by PCR, Southern blotting, RT-PCR and Northern blotting analysis. After stress treatment for 6 weeks with 200mmol/L NaCl, transgenic plants survived, while wild-type plants did not. After 3 days of stress treatment through different concentrations of NaCl, transgenic plants accumulated higher concentration of Na+ and proline than the control plants. However, the K+ concentration of transgenic plants declined in comparison with the control plants. Moreover, the rutin content of the roots, stems and leaves of transgenic buckwheat increased than those of the control plants. These results showed that it could be possible to improve the salt-tolerance of crops with genetic technology.

  8. Strategies for lung regeneration

    Directory of Open Access Journals (Sweden)

    Thomas H. Petersen

    2011-05-01

    Full Text Available Due to the limited ability of the adult lung to regenerate and the frequency of lung disease, the lung is a tissue that can especially benefit from regenerative medicine. Prospects for lung regeneration have made great strides in the past year. In this review, we summarize recent progress and key challenges for approaches in lung regenerative medicine. With a focus on the matrix components critical for the development of regenerative lung tissues, we discuss possible cell sources for lung regeneration, key matrix effects on cell repopulation, and physical stimuli that will aid in the growth of lung tissues in vitro.

  9. 发根农杆菌K599对菊花活体转化及其高效再生%Hairy Roots Induced by Agrobacterium rhizogenes K599 in Chrysanthemum in Vivo and Plant Regeneration from Hairy Roots

    Institute of Scientific and Technical Information of China (English)

    向太和; 王琳; 蒋欢; 田璟鸾

    2011-01-01

    The transgenic hairy roots were formed on cut leaves of chrysanthemum plantlet by Agrobacterium rhizogenes K599 with frequencies of 88.0%.The calli were induced from hairy roots and plantlets were regenerated from calli at rates of 75.0% and 63.3% respectively.The transgenic hairy roots and plantlet were confirmed by PCR analysis with primers from K599 Ri plasmid rolC gene.Quantitative RT-PCR(qRT-PCR)analysis showed that rolC gene was normally expressed in the regenerated transgenic plants.Regenerated plants harbored a character of dwarf,more hairy roots and flowering normally.Organism in vivo directly as a receptor for infection by Agrobacterium rhizogenes K599,it overcame the emergence of false-positive transgenic hairy roots.In addition,using the process of hairy roots propagation characteristics of the top growing point region sterile and the interception of adventitious roots near the growing point to the top for subculture,combined with cefotaxime sterilization,it can inhibit and kill the Agrobacterium effectively.In the subsequent callus induction and redifferentiation from hairy roots,it is no antibiotics added to medium for killing Agrobacterium.It genetically enhanced efficiency of plant regeneration.The transgenic hairy roots were induced by Agrobacterium rhizogenes K599 in chrysanthemum in vivo and plant regenerated from hairy roots highly efficiently in the study.It is useful to dwarf breeding and the target gene transformation of chrysanthemum.%发根农杆菌K599侵染菊花无菌苗刻伤的叶片形成转基因不定根,生根频率为88.0%;不定根经过诱导培养形成愈伤组织,并再生完整植株,愈伤组织诱导率和分化率分别为75.0%和63.3%。诱导的不定根和再生植株经过PCR鉴定含有K599 Ri质粒中的rolC基因,qRT-PCR检测显示rolC基因在再生转基因植株中实现了正常表达。再生植株表现出矮缩、多毛状根特征,并能正常开花。建立的利用活体材料

  10. The IPE Database: providing information on plant design, core damage frequency and containment performance

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, J.R.; Lin, C.C.; Pratt, W.T. [Brookhaven National Lab., Upton, NY (United States); Su, T.; Danziger, L. [U.S. Nuclear Regulartory Commission, No. Bethesda, MD (United States)

    1996-08-01

    A database, called the IPE Database has been developed that stores data obtained from the Individual Plant Examinations (IPEs) which licensees of nuclear power plants have conducted in response to the Nuclear Regulatory Commission`s (NRC) Generic Letter GL88-20. The IPE Database is a collection of linked files which store information about plant design, core damage frequency (CDF), and containment performance in a uniform, structured way. The information contained in the various files is based on data contained in the IPE submittals. The information extracted from the submittals and entered into the IPE Database can be manipulated so that queries regarding individual or groups of plants can be answered using the IPE Database.

  11. Influence of microwave frequency electromagnetic radiation on terpene emission and content in aromatic plants.

    Science.gov (United States)

    Soran, Maria-Loredana; Stan, Manuela; Niinemets, Ülo; Copolovici, Lucian

    2014-09-15

    Influence of environmental stress factors on both crop and wild plants of nutritional value is an important research topic. The past research has focused on rising temperatures, drought, soil salinity and toxicity, but the potential effects of increased environmental contamination by human-generated electromagnetic radiation on plants have little been studied. Here we studied the influence of microwave irradiation at bands corresponding to wireless router (WLAN) and mobile devices (GSM) on leaf anatomy, essential oil content and volatile emissions in Petroselinum crispum, Apium graveolens and Anethum graveolens. Microwave irradiation resulted in thinner cell walls, smaller chloroplasts and mitochondria, and enhanced emissions of volatile compounds, in particular, monoterpenes and green leaf volatiles (GLV). These effects were stronger for WLAN-frequency microwaves. Essential oil content was enhanced by GSM-frequency microwaves, but the effect of WLAN-frequency microwaves was inhibitory. There was a direct relationship between microwave-induced structural and chemical modifications of the three plant species studied. These data collectively demonstrate that human-generated microwave pollution can potentially constitute a stress to the plants. Copyright © 2014 Elsevier GmbH. All rights reserved.

  12. Breeding and Simple-rapid Regeneration Protocol for Jisheng 1 with Glandless Trait and High-frequency Somatic Embryo Production Ability

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Most of model cotton varieties used in tissue culture have glands on both the reproductive and vegetative parts of the plant.These glands contain compounds that are toxic to human and non-ruminant animals.The presence of these compounds limits their usage as food and feed.To obtain a glandless cotton variety with high-frequency somatic embryo production ability,27 glandless varieties were

  13. Direct gene transfer study and transgenic plant regeneration after electroporation into mesophyll protoplasts of Pelargonium x hortorum, 'Panaché Sud'.

    Science.gov (United States)

    Hassanein, Anber; Hamama, Latifa; Loridon, Karine; Dorion, Noëlle

    2009-10-01

    Direct genetic transformation of mesophyll protoplasts was studied in Pelargonium x hortorum. Calcein and green-fluorescent protein (GFP) gene were used to set up the process. Electroporation (three electric pulses from a 33-microF capacitor in a 250-V cm(-1) electric field) was more efficient than PEG 6000 for membrane permeation, protoplast survival and cell division. Transient expression of GFP was detected in 33-36% of electroporated protoplasts after 2 days and further in colonies. A protoplast suspension conductivity of >1,500 microS cm(-1) allowed high colony formation and plant regeneration. Stable transformation was obtained using the plasmid FAJ3000 containing uidA and nptII genes. When selection (50 mg l(-1) kanamycin) was achieved 6 weeks after electroporation, regenerated shoots were able to grow and root on 100 mg l(-1) kanamycin. The maximum transformation efficiency was 4.5%, based on the number of colonies producing kanamycin-resistant rooted plants or 0.7% based on the number of cultured protoplasts. Polymerase chain reaction (PCR) analysis on in vitro micropropagated plants showed that 18 clones out of 20 contained the nptII gene, while the uidA gene was absent. These results were confirmed after PCR analyses of five glasshouse-acclimatized clones.

  14. Plant-soil feedbacks promote negative frequency dependence in the coexistence of two aridland grasses.

    Science.gov (United States)

    Chung, Y Anny; Rudgers, Jennifer A

    2016-07-27

    Understanding the mechanisms of species coexistence is key to predicting patterns of species diversity. Historically, the ecological paradigm has been that species coexist by partitioning resources: as a species increases in abundance, self-limitation kicks in, because species-specific resources decline. However, determining coexistence mechanisms has been a particular puzzle for sedentary organisms with high overlap in their resource requirements, such as plants. Recent evidence suggests that plant-associated microbes could generate the stabilizing self-limitation (negative frequency dependence) that is required for species coexistence. Here, we test the key assumption that plant-microbe feedbacks cause such self-limitation. We used competition experiments and modelling to evaluate how two common groups of soil microbes (rhizospheric microbes and biological soil crusts) influenced the self-limitation of two competing desert grass species. Negative feedbacks between the dominant plant competitor and its rhizospheric microbes magnified self-limitation, whereas beneficial interactions between both plant species and biological soil crusts partly counteracted this stabilizing effect. Plant-microbe interactions have received relatively little attention as drivers of vegetation dynamics in dry land ecosystems. Our results suggest that microbial mechanisms can contribute to patterns of plant coexistence in arid grasslands.

  15. The evaluation of the activity of medicinal remedies of plant and animal origin on the regeneration of the earthworms′ tail segments

    Directory of Open Access Journals (Sweden)

    Viktor Alexandrovich Bybin

    2015-01-01

    Full Text Available Now, in the global community there is enough hard recommendation to replace the vertebrate test animals into simpler organisms at the development, testing, and evaluation of the quality pharmaceuticals. The feature of planarian to regenerate in new individual planarian from a piece, which is only 1/7 of the original animal, allowed to create the alternative methods of testing of drugs, dietary supplements, water quality, influence of electromagnetic fields, and other radiations. The tests on planarian can replace the ones that are held today on mammals. However, the lacks of the bioassays based on the planarian regeneration are the need for complex and expensive video equipment for recording the regrowth of worms′ body, the difficulties of culturing of flatworms and fairly long period of response. These difficulties can be avoided by using another group of the worms of type Annelida. The new individual can be fully recovered only from the front half of the body in many species of earthworms. Thus, the influence of the pharmaceuticals from earthworms, mummy, and Orthilia secunda on the ability of earthworms to regenerate lost tail segments has been investigated. The relations of the activity of preparations tested with doses and the time of the storage have been revealed. The principal possibility of applicability of the test reaction studied as a way to evaluate the effects and quality of remedies based on medicinal plants and earthworms has been shown.

  16. 蝴蝶兰快速经济有效繁殖技术的研究%A Reliable Protocol for Plant Regeneration from Pedicel Axillary Bud of Phalaenopsis in vitro

    Institute of Scientific and Technical Information of China (English)

    王敬文; 明凤; 叶鸣明; 董玉光; 梁斌; 陈龙英; 沈大棱

    2004-01-01

    以蝴蝶兰(Phalaenopsis)花梗腋芽为外植体,研究出一种高效、简便的诱导原球茎(Protocorm)的方法.在不含其他有机添加物,只添加BA (3 mg/L)+NAA (0.1 mg/L)的MS培养基中,原球茎诱导效率达80%. 相同培养基继代,4周内即可发育成幼苗.在含有IAA(0.1 mg/L)的MS培养基中,40%的幼苗可以诱导生根,并移植成功.由于此方法简便、经济有效,可应用于工厂化生产,而且获得的优质原球茎也为进一步的遗传改良提供材料.%An efficient and simple method of high frequency protocorm regeneration from pedicel axillary bud of Phalaenopsis is described. Pedicel axillary buds were cultured on Murashige and Skoog's basal medium (MS) with combinations of 6-benzylaminopurine (BA) (2-3 mg/L) and α-naphthaleneacetic acid (NAA) (0.1-0.5 mg/L). Medium supplemented with 3 mg/L BA in combination with 0.1 mg/LNAA produced the best response in protocorm occurrence(80%) without addition of any organic material. On subculture to the same medium, protocorm produced the shoots within 4 weeks of culture and well developing shoots were obtained separately. 40% of developed shoots produced root on medium supplemented with 0.1 mg/L IAA and the plants were transferred to moss for growth. Because of the simplicity for culture medium ingredient, it is a reliable protocol for plant regeneration of Phalaenopsis factory production in developing country and is also useful to genetic improvement programs.

  17. Culture in vitro and Plant Regeneration from Roots of Citrus paradisi Macf.Seedlings%葡萄柚(Citrus paradisi Macf.)实生苗根段的离体培养及植株再生研究

    Institute of Scientific and Technical Information of China (English)

    陶燕蓝; 蓝增全; 吴田

    2014-01-01

    Objective]The objective of the study was to establish regeneration system of C.para-disi in vitro and to provide useful references for the application of genetic transformation tech-nique.[Method]The roots of aseptic seedlings germinated from the seeds of 10 grapefruit varie-ties were cultured in vitro to obtain regeneration plants in the medium with different hormones and concentrations.[Results]The callus were observed in the medium MS+0.5 mg/L 6-BA+0.5 mg/L NAA and Perlist had the highest callus induction frequency (87.95%).The differentia-tion of adventitious buds was observed in the medium MS+2.0 mg/L 6-BA+0.5 mg/L NAA and Star Ruby had the largest differentiation rate of adventitious buds (37.84%).The regeneration buds were multiplied in the medium MS+2.0 mg/L 6-BA+0.2 mg/L NAA.The adventitious roots were induced in the medium 1/2 MS +1.0 mg/L IBA and the regeneration plants finally were obtained.The survival rates of regenerative plant ranged from 75.47% to 88.40%.[Con-clusion]The regeneration systems of 6 grapefruit varieties were established based on the study.%【目的】建立葡萄柚(Citrus paradisi Macf.)离体再生体系,为后续遗传转化体系的建立奠定基础。【方法】以10个葡萄柚品种种子萌发的无菌苗根段为材料,在附加不同植物激素种类及浓度的培养基上进行离体培养,并获得再生植株。【结果】在 MS+0.5 mg/L 6-BA+0.5 mg/L NAA 培养基上培养可以诱导出愈伤组织,其中“帕利斯”的诱导率最高,达87.95%;在培养基 MS+2.0 mg/L 6-BA+0.5 mg/L NAA 可分化出丛生芽,其中“星路比”分化率最高为37.84%;分化出的丛生芽在 MS+2.0 mg/L 6-BA+0.2 mg/L NAA 培养基上可以进行增殖培养;在1/2 MS+1.0 mg/L IBA 上可诱导出不定根,形成完整再生植株。炼苗移栽成活率均可达75.47%~88.40%。【结论】通过对10个葡萄柚品种根段

  18. Plant frequency and distribution on high-lead soil near Leadhills, Lanarkshire

    Energy Technology Data Exchange (ETDEWEB)

    Oxbrow, A.; Moffat, J.

    1979-06-01

    The mean frequency of plants along a transect descending Wanlock Dod, near Leadhills, Lanarkshire, Scotland was determined by quadrat analysis. The results obtained strongly suggested that lead tolerant ecotypes of Agrostis tenuis, Nardus stricta and Potentialla erecta were present above known lead veins. The evidence for Vaccinium myrtillus was less certain. Other species appeared to be affected by soil moisture content, grazing pressure and climatic factors. The areas above known lead veins exhibited a larger diversity of species than the areas between veins.

  19. Effect of low temperature on dormancy breaking and growth after planting in lily bulblets regenerated in vitro

    NARCIS (Netherlands)

    Langens-Gerrits, M.M.; Miller, W.B.; Croes, A.; Klerk, de G.J.M.

    2003-01-01

    Lilies regenerating on scale segments may develop dormancy in vitro depending on the culture conditions. The dormancy is broken by storage for several weeks at a low temperature ( 5 degreesC). The effect of the low temperature on sprouting, time of leaf emergence and further bulb growth was studied.

  20. IPE Data Base: Plant design, core damage frequency and containment performance information

    Energy Technology Data Exchange (ETDEWEB)

    Lehner, J.; Lin, C.C.; Pratt, W.T. [Brookhaven National Lab., Upton, NY (United States); Su, T.; Danziger, L. [Nuclear Regulatory Commission, Rockville, MD (United States)

    1995-12-31

    This data base stores data obtained from the Individual Plant Examinations (IPEs) which licensees of nuclear power plants have conducted in response to NRC`s Generic Letter GL88-20. The IPE Data Base is a collection of linked files which store information about plant design, core damage frequency, and containment performance in a uniform, structured way. The information contined in the various files is based on data contained in the IPE submittals. The information extracted from the submittals and entered into the IPE Data Base can be maniulated so that queries regarding individual or groups of plants can be answered using the IPE Data Base. The IPE Data Base supports detailed inquiries into the characteristics of individual plants or classes of plants. Progress has been made on the IPE Data Base and it is largely complete. Recent focus has been the development of a user friendly version which is menu driven and allows the user to ask queries of varying complexity easily, without the need to become familiar with particular data base formats or conventions such as those of DBase IV or Microsoft Access. The user can obtain the information he desired by quickly moving through a series of on-screen menus and ``clicking`` on appropriate choices. In this way even a first time user can benefit from the large amount of information stored in the IPE Data Base without the need of a learning period.

  1. Increase of homologous recombination frequency in vascular tissue of Arabidopsis plants exposed to salt stress.

    Science.gov (United States)

    Boyko, Alex; Hudson, Darryl; Bhomkar, Prasanna; Kathiria, Palak; Kovalchuk, Igor

    2006-06-01

    Here we analyzed the influence of salt stress on plant genome stability. Homologous recombination events were detected in transgenic Arabidopsis plants that carried in their genome a beta-glucuronidase recombination marker. Recombination events were scored as blue sectors using a stereo microscope. Exposure to 50 mM salt resulted in a 3.0-fold increase in recombination frequency. To analyze the organ and tissue specificity of recombination events, we examined cross-sections of leaves, stems and roots. We found that nearly 30% of recombination events in plants grown under normal conditions and nearly 50% of events in plants grown on salt were undetected by the conventional method. Most of the recombination events represented a cluster/group of cells (12 on average), although events with single cells were also detected. Recombination events were very frequent in leaf mesophyll cells. On average, individual recombination events located on leaves contained more cells than events located on roots or stems. Analysis of recombination events in cross-sectioned tissue of salt-treated plants revealed a shift in the distribution of recombination events towards the vascular tissue. We discuss the significance of the finding for plant stress physiology.

  2. Changes to DNA methylation and homologous recombination frequency in the progeny of stressed plants.

    Science.gov (United States)

    Migicovsky, Zoë; Kovalchuk, Igor

    2013-02-01

    Plants undergo changes in response to biotic and abiotic stresses that help them adjust and survive. Some of these changes may even be passed on to progeny and eventually lead to adaptive evolution. Transgenerational changes in response to stress include alterations in DNA methylation and changes in homologous recombination frequency (HRF). The progeny of plants that were stressed often show elevated HRF as well as genomic hypermethylation, although specific loci that are beneficial in times of stress may be hypomethylated. One of the possible mechanisms responsible for passing the memory to the progeny involves small interfering RNAs; Dicer-like proteins, DCL2 and DCL3, are in part required for this process. However, while epigenetic modifications are often present in the untreated progeny of stressed plants, they are not usually sustained for multiple unexposed generations. Still, transgenerational inheritance of such changes has already begun to provide evidence for an important role of epigenetics in enhancing stress resistance.

  3. Influence of Removal of a Non-native Tree Species Mimosa caesalpiniifolia Benth. on the Regenerating Plant Communities in a Tropical Semideciduous Forest Under Restoration in Brazil

    Science.gov (United States)

    Podadera, Diego S.; Engel, Vera L.; Parrotta, John A.; Machado, Deivid L.; Sato, Luciane M.; Durigan, Giselda

    2015-11-01

    Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species ( Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified "taungya" agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings.

  4. Variable Frequency Operations of an Offshore Wind Power Plant with HVDC-VSC: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Gevorgian, V.; Singh, M.; Muljadi, E.

    2011-12-01

    In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated. Based on DOE study, wind power generation may reach 330 GW by 2030 at the level of penetration of 20% of the total energy production. From this amount of wind power, 54 GW of wind power will be generated at offshore wind power plants. The deployment of offshore wind power plants requires power transmission from the plant to the load center inland. Since this power transmission requires submarine cable, there is a need to use High-Voltage Direct Current (HVDC) transmission. Otherwise, if the power is transmitted via alternating current, the reactive power generated by the cable capacitance may cause an excessive over voltage in the middle of the transmission distance which requires unnecessary oversized cable voltage breakdown capability. The use of HVDC is usually required for transmission distance longer than 50 kilometers of submarine cables to be economical. The use of HVDC brings another advantage; it is capable of operating at variable frequency. The inland substation will be operated to 60 Hz synched with the grid, the offshore substation can be operated at variable frequency, thus allowing the wind power plant to be operated at constant Volt/Hz. In this paper, a constant Volt/Hz operation applied to the Type 1 wind turbine generator. Various control aspects of Type 1 generators at the plant level and at the turbine level will be investigated.

  5. Effect of plant growth regulators and explant types on regeneration and micropropagation of a commercial strawberry cultivar (Fragaria ×ananassa cv. Selva

    Directory of Open Access Journals (Sweden)

    G. Madani

    2013-10-01

    Full Text Available Strawberry (Fragaria× ananassa L. is an important horticultural product that is highly acceptable because of its desirable taste, flavor, mineral elements, vitamins and secondary metabolites. Conventionally, strawberries are vegetatively propagated by runners arising from axillary buds on the plant crown. Plant propagation through runner produces a limited number of propagules. In the view of mass propagation and transformation, it is highly desirable to optimize methods of rapid, efficient and large scale multiplication of Fragaria X ananassa Duch. through tissue culture. In present study, developing an effective protocol for regeneration of strawberry cv. Selva, different explants (leaf disk, shoot tips and hypocotyls and media modifications were examined. The best response towards shoot induction was observed on shoot tip explants cultured on MS medium supplemented with 2 mg/l of BAP and IAA. Direct shoots emerged from hypocotyls grown on MS medium supplemented by 2,4-D, BAP and TDZ at 0.01, 0.1 and 1 mg/l respectively. Indirect shoot regeneration was produced from hypocotyls on MS medium containing 2 mg/l of BAP. Using activated charcoal enhanced explants proliferation on culture media due to decreasing the toxic metabolites, phenolic exudation and adsorption of inhibitory compounds.

  6. Evaluation for Plant Regeneration Potential of Root Explants in Echinacea purpurea%松果菊根外植体植株再生能力的评价

    Institute of Scientific and Technical Information of China (English)

    Dahanayake NILANTHI; 赵福成; 杨跃生; 吴鸿

    2009-01-01

    为了评价松果菊Echinacea purpurea L.根外植体的再生能力,将从松果菊无菌小苗得到的根外植体和叶片以及叶柄外植体接种到含有不同种类和浓度的细胞分裂素和生长素的培养基上,诱导不定芽的再生.结果表明,在多数情况下,根外植体的再生能力显著高于叶片,和叶柄类似.0.3 mg/L的苄基腺嘌呤和0.01 mg/L的萘乙酸是诱导根外植体不定芽再生最合适的激素种类和质量浓度组合.根外植体培养的不定芽再生频率为100%,每个根外植体得到再生芽1.75个.当把这些由根再生的不定芽从母体组织切开并转移培养到含有0.01 mg/L萘乙酸的培养基后,很容易生根并成为完整的植株.可见根是组培快繁松果菊理想的外植体材料.%For evaluation of the plant regeneration potential of root explants, explants of root, leaf and petiole were taken from in vitro grown purple coneflower, Echinacea purpurea L. Plantlets and cultured on adventitious bud inducing media with different cytokinins and auxins at various concentrations. In most of the cases, the regeneration potential of root explants was much higher than that of leaf ones and similar to that of petiole explants, and a combination of 0.3 mg/L benzyladeine with 0.01 mg/L naphthaleneacetic acid was the most effective combination and concentrations for inducing adventitious bud regen-eration. Although the best result of bud regeneration was obtained from culture of petiole explants, a good result in regenera-tion rate of 100% and a high number of 1.75 buds per exphnt were obtained from culture of root explants. Buds regenerated from root explants initiated roots and became intact plants readily upon transfer to a medium containing 0.01 mg/L naphthale-neacetic acid. Results of the experiments indicated that root was an ideal explant source for rapid propagation by means of tis-sue culture in this plant species.

  7. Salts and nutrients present in regenerated waters induce changes in water relations, antioxidative metabolism, ion accumulation and restricted ion uptake in Myrtus communis L. plants.

    Science.gov (United States)

    Acosta-Motos, José R; Alvarez, Sara; Barba-Espín, Gregorio; Hernández, José A; Sánchez-Blanco, María J

    2014-12-01

    The use of reclaimed water (RW) constitutes a valuable strategy for the efficient management of water and nutrients in landscaping. However, RW may contain levels of toxic ions, affecting plant production or quality, a very important aspect for ornamental plants. The present paper evaluates the effect of different quality RWs on physiological and biochemical parameters and the recovery capacity in Myrtus communis L. plants. M. communis plants were submitted to 3 irrigation treatments with RW from different sources (22 weeks): RW1 (1.7 dS m(-1)), RW2 (4.0 dS m(-1)) and RW3 (8.0 dS m(-1)) and one control (C, 0.8 dS m(-1)). During a recovery period of 11 weeks, all plants were irrigated with the control water. The RW treatments did not negatively affect plant growth, while RW2 even led to an increase in biomass. After recovery,only plants irrigated with RW3 showed some negative effects on growth, which was related to a decrease in the net photosynthesis rate, higher Na accumulation and a reduction in K levels. An increase in salinity was accompanied by decreases in leaf water potential, relative water content and gas exchange parameters, and increases in Na and Cl uptake. Plants accumulated Na in roots and restricted its translocation to the aerial part. The highest salinity levels produced oxidative stress, as seen from the rise in electrolyte leakage and lipid peroxidation. The use of regenerated water together with carefully managed drainage practices, which avoid the accumulation of salt by the substrate, will provide economic and environmental benefits.

  8. Efficient regeneration of pearl millet (Pennisetum glaucum (L.) R. Br.) from shoot tip cultures.

    Science.gov (United States)

    Mythili, P K; Madhavi, A; Reddy, V D; Seetharama, N

    2001-12-01

    A simple, genotype-independent and efficient method for plant regeneration using shoot tip explants of pearl millet (Pennisetum glaucum) was established. Linsmaier and Skoog (LS) medium supplemented with 2,4-dichloro-phenoxyacetic acid (2.5 mg l(-1)) and kinetin (0. 2 mg l(-1)) was used for induction of embryogenic calli. Development of numerous somatic embryos was observed within 10 days after transferring onto Murashige and Skoog (MS) medium supplemented with 6-benzyl aminopurine (2 mg l(-1)) and indole 3-butyric acid (0. 5 mg l(-1)) under light (16 hr photoperiod). Histological observations confirmed the origin of somatic pro-embryoids and globular embryoids. Regenerated plants established in soil, grew normally and produced fertile seeds. RAPD analysis also revealed genetic uniformity of the regenerants. The short duration of time taken for regeneration (30-35 days) and its high frequency (78-87%) makes this system highly suitable for applications such as genetic transformation.

  9. Plant Regeneration from Stem-Derived Protoplasts of Solanum lycopersicoides%类番茄茄茎段原生质体再生成株的研究

    Institute of Scientific and Technical Information of China (English)

    张长远; 吴定华

    2001-01-01

    利用类番茄茄(Solamum lycopersicoides Dun.)无菌苗幼嫩茎段酶解获得大量原生质体(个)(2×106/g),将原生质体密度稀释至1×105/mL于HMA培养基中培养,则10d左右出现小细胞团,38~40d形成肉眼可见的小愈伤组织(1~1.5mm),转移至MC增殖培养基2周后,再转移到15#分化培养基诱导出芽,切取芽体转入50P培养基诱发根原基,再转入50#发根培养基形成发达根系,成为再生植株,整个再生周期80~90d,再生植株移植至土壤中均能正常生长、开花。%A procedure for protoplast isolation, culture and plant regeneration has been developed for solanum lycopersicoides. Stem-protoplasts were diluted to 1×105/mL and cultured in HMA medium, cell colonies (20~30 cells) appeared after 10 days, micro calli (1~1.5mm) formed after 38~40 days from initially culturing. The micro calli were transferred to MC greenig medium for 2 weeks. The green calli were transferred to 15# medium for shoot inducting. The shoots which excised from the callus were transferred to test tubes with 50p medium first for root promoting about 3~4 days and then transferred to 50# rooting medium. Plants regenerated after 80~90 days after initially culturing. All the plants which potted in soil could vigorously grow and blossom.

  10. Establishment of High-frequency Regeneration System from Cotyledons with Petiole in Radish%萝卜带柄子叶高频再生体系的建立

    Institute of Scientific and Technical Information of China (English)

    李海萍; 张鲁刚; 张静; 茹磊; 刘学成; 孙希禄

    2011-01-01

    以11份萝卜(Raphanus sativus)基因型为材料进行子叶离体培养研究,筛选出具有较高再生率的基因型进行实验,考察基因型、外植体类型、激素配比和苗龄等因素对萝卜再生的影响.结果表明:萝卜离体再生的最佳外植体为全子叶-叶柄,最适苗龄为4天,最适培养基为MS+6 mg·L-16-BA+0.05 mg·L-1NAA,再生率高达86.95%,再生系数为1.80.该研究为进行萝卜遗传转化实验奠定了良好基础.%We studied in vitro culture regeneration from cotyledons of 11 genotypes of radish. Those genotypes, which have a high rate of regeneration, were used as the test materials for subsequent experiments of explant type, hormone ratio, and seedling age. The regenerated plantlets, which generated roots well, were transplanted into the field. The entire cotyledon with a petiole is the optimal regeneration explant. Four days of seedling age is suitable to induce adventitious shoots. The maximum frequency of shoot regeneration was 86.95% obtained from cotyledons of Z3 in the medium Murishige and Skoog + 6 mg·L-1 6-BA + 0.05 mg·L-1 NAA, and the regeneration coefficient reached 1.80. These results set the basis for radish genetic transformation.

  11. Implications of crude oil pollution on natural regeneration of plant spe-cies in an oil-producing community in the Niger Delta Region of Nigeria

    Institute of Scientific and Technical Information of China (English)

    U.D Chima; G. Vure

    2014-01-01

    The study evaluated the impact of crude oil pollution on natu-ral regeneration of plant species in a major oil-producing community in the Niger Delta region of Nigeria. Three sites-unpolluted site (US), polluted and untreated site (PUS), and polluted and treated site (PTS)-were purposively chosen for the study. The seedling emergence method was used to evaluate soil seed banks in the various sites at two depths, 0 to 10 cm and 10 to 20 cm. Woody-plant species richness, abundance, and diversity were higher in the US seed bank than in the PUS and PTS seed banks. The highest number of non-woody plants was observed in the US, followed by the PTS, and then the PUS. Both species richness and diversity of non-woody plants were highest at the US, followed by the PUS, and lowest in the PTS. Woody species in the US seed bank were 87.5% and 80% dissimilar with those of the PUS and PTS at 0-10 cm and 10-20 cm respectively. No variation was observed between woody species in the PUS and PTS seed banks. Non-woody species at 0-10 cm US seed bank were 73.08% dissimilar with those of PUS at the two soil depths and 81.48/88.46%dissimilar with those of the 0-10/10-20 cm of the PTS respectively. At 10-20 cm, non-woody species of the US were 69.66% dissimilar with those from each of the two soil depths in PUS;and 73.91/81.82% dissimilar with those of 0-10/10-20 cm of the PTS respectively. Non-woody species variation between the PUS and PTS was higher at 10-20 cm than 0-10 cm. The poor seed bank attributes at the polluted sites demonstrates that crude oil pollution negatively af-fected the natural regeneration potential of the native flora because soil seed banks serve as the building blocks for plant succession. Thorough remediation and enrichment planting are recommended to support the recovery process of vegetation in the polluted areas.

  12. Liver regeneration.

    Science.gov (United States)

    Mao, Shennen A; Glorioso, Jaime M; Nyberg, Scott L

    2014-04-01

    The liver is unique in its ability to regenerate in response to injury. A number of evolutionary safeguards have allowed the liver to continue to perform its complex functions despite significant injury. Increased understanding of the regenerative process has significant benefit in the treatment of liver failure. Furthermore, understanding of liver regeneration may shed light on the development of cancer within the cirrhotic liver. This review provides an overview of the models of study currently used in liver regeneration, the molecular basis of liver regeneration, and the role of liver progenitor cells in regeneration of the liver. Specific focus is placed on clinical applications of current knowledge in liver regeneration, including small-for-size liver transplant. Furthermore, cutting-edge topics in liver regeneration, including in vivo animal models for xenogeneic human hepatocyte expansion and the use of decellularized liver matrices as a 3-dimensional scaffold for liver repopulation, are proposed. Unfortunately, despite 50 years of intense study, many gaps remain in the scientific understanding of liver regeneration.

  13. Waste sulphuric acid regeneration plants and on-site services%废硫酸再生装置与现场服务

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Waste sulphuric acid regeneration has matured to provide a robust and reliable way for recycling the waste sulphuric acid using a variety of sources. Design features of MECS waste sulphuric acid regeneration plants and on-site service for sulphuric users provided by Rhodia are described. Rhodia's service includes a patented storage tank cleaning technology, which can not only clean out and recover acid sludge from storage tanks, but also avoid confined space entry.%废硫酸再生技术已经成熟,为回收利用各种来源的废硫酸提供了一条稳健、可靠的途径。主要阐述了MECS废酸再生装置的设计特点和罗地亚为硫酸用户提供的现场服务。罗地亚的现场服务包括一种专利储罐清洗技术,该技术不但可清除并回收罐底酸泥,而且可避免受限空间的进入。

  14. Plant regeneration from cotyledonary explants of Eucalyptus camaldulensis Regeneração de plantas de Eucalyptus camaldulensis a partir das explantes cotiledonares

    Directory of Open Access Journals (Sweden)

    Roberson Dibax

    2005-08-01

    Full Text Available Breeding methods based on genetic transformation techniques need to be implemented for Eucalyptus camaldulensis to shorten the long breeding cycles and avoid manipulation of adult trees; that requires the development of plant regeneration protocols enabling development of plants from transformed tissues. The present work aimed to optimise the regeneration process already established for the species. Cotyledonary leaves of E. camaldulensis were cultured in MS medium supplemented with naphthaleneacetic acid (NAA and 6-benzylaminopurine (BAP combinations. The most efficient treatment for bud indirect regeneration (2.7 µmol L-1 NAA and 4.44 µmol L-1 BAP was used for further experiments. When explants were kept in the dark during the first 30 days, the percentage of explants forming calluses increased and explant necrosis was reduced in comparison with light-cultured explants. Mineral medium modifications were compared and half-strength MS mineral medium turned out to be as efficient as full-strength medium, producing 54% and 47% of explants with buds, respectively. For shoot elongation, MS medium with half-strength nitrate and ammonium salts, and 0.2% activated charcoal yielded rooted shoots 1 to 8 cm high after one month. The procedure is an efficient protocol for E. camadulensis plant regeneration, reducing the stages necessary for the obtention of complete plants.A implementação, para espécies florestais, de técnicas de melhoramento baseadas em métodos de transformação genética, permitirá reduzir os longos ciclos de melhoramento e evitar a manipulação de árvores adultas. Isto implica dispor de um protocolo de regeneração que permita o desenvolvimento de plantas a partir de tecidos transformados. Este trabalho teve como objetivo otimizar este protocolo de regeneração para Eucalyptus camaldulensis. Folhas cotiledonares foram cultivadas em meio de cultura MS suplementado com combinações de ácido naftalenoacético (ANA e 6

  15. An Efficient System for Plant Regeneration from Immature Embryo of Chinese Jujube%枣未成熟胚高效再生体系研究

    Institute of Scientific and Technical Information of China (English)

    崔秀梅; 王玖瑞; 刘孟军; 代丽; 郭敬丽

    2012-01-01

    An efficient system for plant regeneration from immature embryo of Chinese jujube was established by u-sing two callivars of male sterile No. 3CJMS3) and 'Jinmangguozao'. The results showed that the plant regeneration could be achieved by two types of procedures: direct embryo germination and generation of callus of cotyledon. Cold treatment could efficiently accelerate the direct plant regeneration from immature embryo. The plant regeneration rate of immature embryos, which were kept at 0~4℃ for 60 days and then inoculated in medium MS + sugar 30 g ? L-1 + agar 3. 3 g ? L-1, was as high as 93. 3%. Callus could be induced from 98. 9% of cotyledons damaged during smashing stones in medium MS +maltose 20 g ? L-1 +agar 3. 3 g ? L-1 +TDZ 1. 0 mg ? L-1 +NAA 0. 2 mg ? L-1 within 40 days. Adventitious buds occurred in 74.1% of the callus cultured in medium MS + maltose 20 g ? L-1 +agar 3. 3 g ? L-1 +TDZ 1. 0 mg ? L-1 for 40 days with cluster buds rate of 70. 4%. 1/2MS + sugar 20 g ?. L-1 + agar 3. 3 g ? L-1 + IBA 1. 0 mg ? L-1 + IAA 0. 01 mg ? L-1 was proper rooting medium and the rooting rate reached 80. 8% in 40 days.%以枣树雄性不育3号(JMS3)和金芒果枣为材料,建立了枣树未成熟胚高效再生植株体系.对枣未成熟胚高效再生体系研究结果表明:枣未成熟胚可以通过直接萌发和经子叶发生愈伤两条途径再生完整植株,冷藏处理是促进未成熟胚直接成苗的有效方法.枣未成熟胚经0~4℃冷藏60 d,接种在MS+蔗糖30 g· L-1+琼脂3.3g·L-1培养基上,胚直接成苗率高达93.3%.将去除核壳时受损伤胚的子叶接种到MS+麦芽糖20g·L-1+琼脂3.3 g·L-1+TDZ 1.0 mg·L-1+NAA 0.2 mg·L-培养基上,40 d后出愈率为98.9%.所得愈伤经MS+麦芽糖20g· L-1-+琼脂3.3 g·L-1+TDZ 1.0 mg·L-1诱导40 d后出芽率可达74.1%,丛生芽率达70.4%.在生根培养基1/2MS+蔗糖20g· L-1+琼脂3.3 g·L-1+IBA1.0mg·L-1+IAA0.01 mg· L-1上40 d后生根率为80.8%.

  16. System frequency support of permanent magnet synchronous generator-based wind power plant

    Science.gov (United States)

    Wu, Ziping

    With ever-increasing penetration of wind power into modern electric grids all over the world, a trending replacement of conventional synchronous generators by large wind power plants will likely result in the poor overall frequency regulation performance. On the other hand, permanent magnet synchronous generator wind Turbine System (PMSG-WTG) with full power back to back converters tends to become one of the most promising wind turbine technologies thanks to various advantages. It possesses a significant amount of kinetic energy stored in the rotating mass of turbine blades, which can be utilized to enhance the total inertia of power system. Additionally, the deloaded operation and decoupled control of active and reactive power make it possible for PMSG-WTG to provide a fast frequency regulation through full-power converter. First of all, a comprehensive and in-depth survey is conducted to analyze the motivations for incorporating the inertial response and frequency regulation of VSWT into the system frequency regulation. Besides, control classifications, fundamental control concepts and advanced control schemes implemented for auxiliary frequency support of individual WT or wind power plant are elaborated along with a comparison of the potential frequency regulation capabilities of four major types of WTs. Secondly, a Controls Advanced Research Turbine2-Permanent Magnet Synchronous Generator wind turbine (CART2-PMSG) integrated model representing the typical configuration and operation characteristics of PMSG-WT is established in Matlab/Simulink,. Meanwhile, two different rotor-side converter control schemes, including rotor speed-based control and active power-based control, are integrated into this CART2-PMSG integrated model to perform Maximum Power Point Tracking (MPPT) operation over a wide range of wind speeds, respectively. Thirdly, a novel comprehensive frequency regulation (CFR) control scheme is developed and implemented into the CART2-PMSG model based

  17. Model-based calculating tool for pollen-mediated gene flow frequencies in plants.

    Science.gov (United States)

    Lei, Wang; Bao-Rong, Lu

    2016-12-30

    The potential social-economic and environmental impacts caused by transgene flow from genetically engineered (GE) crops have stimulated worldwide biosafety concerns. To determine transgene flow frequencies resulted from pollination is the first critical step for assessing such impacts, in addition to the determination of transgene expression and fitness in crop-wild hybrid descendants. Two methods are commonly used to estimate pollen-mediated gene flow (PMGF) frequencies: field experimenting and mathematical modeling. Field experiments can provide relatively accurate results but are time/resource consuming. Modeling offers an effective complement for PMGF experimental assessment. However, many published models describe PMGF by mathematical equations and are practically not easy to use. To increase the application of PMGF modeling for the estimation of transgene flow, we established a tool to calculate PMGF frequencies based on a quasi-mechanistic PMGF model for wind-pollination species. This tool includes a calculating program displayed by an easy-operating interface. PMGF frequencies of different plant species can be quickly calculated under different environmental conditions by including a number of biological and wind speed parameters that can be measured in the fields/laboratories or obtained from published data. The tool is freely available in the public domain (http://ecology.fudan.edu.cn/userfiles/cn/files/Tool_Manual.zip). Case studies including rice, wheat, and maize demonstrated similar results between the calculated frequencies based on this tool and those from published PMGF data. This PMGF calculating tool will provide useful information for assessing and monitoring social-economic and environmental impacts caused by transgene flow from GE crops. This tool can also be applied to determine the isolation distances between GE and non-GE crops in a coexistence agro-ecosystem, and to ensure the purity of certified seeds by setting proper isolation distances

  18. [Establishment of embryogenic cell suspension culture and plant regeneration of edible banana Musa acuminata cv. Mas (AA)].

    Science.gov (United States)

    Wei, Yue-Rong; Huang, Xue-Lin; Li, Jia; Huang, Xia; Li, Zhe; Li, Xiao-Ju

    2005-01-01

    Conventional breeding for dual resistance of disease and pest of Musa cultivars remains a difficult endeavor, as the plant is polyploidic and high in sterility. Biotechnological techniques, eg., genetic engineering, in vitro mutation breeding, or protoplast fusion, may overcome the difficulties and improve the germplasm. Establishment of a stable embryogenic cell suspension (ECS) is a prerequisite for any of the biotechnological breeding methods. In this study an embryogenic cell suspension was established from immature male flower of Musa acuminata cv. Mas (AA), a popular commercial variety of banana in the South-East Asian region. After culture for 5-6 months on callus induction media, which consisted of MS salts, different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), 4.1 micromol/L biotin, 5.7 micromol/L indoleacetic acid (IAA), 5.4 micromol/L naphthaleneacetic acid (NAA), other vitamins, 87 mmol/L sucrose, and solidified with 7 g/L agarose, meristematic globules and yellow, friable embryogenic cultures were induced from the explants of 1-15th row young floral hands of immature male flowers. Of the four treatments of 2,4-D, 9 micromol/L was the most effective on the callus induction, it transformed 40.96% and 7.45% of the cultivated male floral hands into callus and embryogenic callus respectively. The explants to produce highest frequency of the embryogenic calli were floral hands of 6 to 12th rows, which generated 5.79% of the embryogenic calli. Suspension cultures were initiated from these embryogenic calli in liquid medium supplemented with 4.5 micromol/L 2, 4-D. After sieving selection of the cultures using a stainless steel metallic strainer with pore sizes of 154 microm at 15 day intervals for 3 months, homogeneous and yellow embryogenic cell suspensions, composed of single cells and small cell aggregates, were established. Based upon the growth quantity and growth rate of ECS, it was determined that the appropriate inoculum was 2.0 mL PCV

  19. Afforestation by natural regeneration or by tree planting: examples of opposite hydrological impacts evidenced by long-term field monitoring in the humid tropics

    Directory of Open Access Journals (Sweden)

    G. Lacombe

    2015-12-01

    Full Text Available The humid tropics are exposed to an unprecedented modernization of agriculture involving rapid and highly-mixed land-use changes with contrasted environmental impacts. Afforestation is often mentioned as an unambiguous solution for restoring ecosystem services and enhancing biodiversity. One consequence of afforestation is the alteration of streamflow variability controlling habitats, water resources and flood risks. We demonstrate that afforestation by tree planting or by natural forest regeneration can induce opposite hydrological changes. An observatory including long-term field measurements of fine-scale land-use mosaics and of hydro-meteorological variables has been operating in several headwater catchments in tropical Southeast Asia since 2001. The GR2M water balance model repeatedly calibrated over successive 1 year periods, and used in simulation mode with specific rainfall input, allowed the hydrological effect of land-use change to be isolated from that of rainfall variability in two of these catchments in Laos and Vietnam. Visual inspection of hydrographs, correlation analyses and trend detection tests allowed causality between land-use changes and changes in seasonal flows to be ascertained. In Laos, the combination of shifting cultivation system (alternation of rice and fallow and the gradual increase of teak tree plantations replacing fallow, led to intricate flow patterns: pluri-annual flow cycles induced by the shifting system, on top of a gradual flow increase over years caused by the spread of the plantation. In Vietnam, the abandonment of continuously cropped areas mixed with patches of tree plantations led to the natural re-growth of forest communities followed by a gradual drop in streamflow. Soil infiltrability controlled by surface crusting is the predominant process explaining why two modes of afforestation (natural regeneration or planting led to opposite changes in flow regime. Given that commercial tree plantations

  20. Studies on Single Cell Culture in vitro in Wheat--The variation of grain protein content and its fractions from regenerated plants

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    On the basis of previous studies dealing with the variation of major agronomic and yield characteristics of regenerated plants derived from single cell culture in vitro of common wheat (Triticum aestivum L.Cultivar NE 7742), the grain protein content and its fractions from regenerated plants with stable agronomic characteristics were studied from 1992 to 1995. The results showed that the variation of grain protein content and its fractions in somaclones from single cell culture in vitro were very significant and the range was very wide (11.53~17.70%). Several types of variation were found in the studies, especially the type with higher protein content than that of cultivar NE 7742 (non-culture parent). Among them, -20.69% of lines the grain protein content was significantly higher than that of NE 7742 and combined with high yielding potential. The tendency of variation of the four protein fractions showed that the variation of albumin was not obvious and maintained the same level as NE7742, the content of gliadin increased in some somaclones and decreased in others. However, the percentages both globulin and glutenin tended to increase. The variation of total amount of structural protein and the ratio between globulin and glutenin tended to increase. The variation of total amount of structural protein and the ratio between globulin and albumm was mainly influenced by globulin under the condition of culture in vitro. The variation of total amount of storage protein and the ratio between gliadin and glutenin was mainly affected by glutenin. The results mentioned above demonstrated that the induction and screening of somaclonal variation could be an effective way in wheat improvement in combining high protein content with high yield.

  1. A rapid and efficient in vitro regeneration system for lettuce (Lactuca sativa L.).

    Science.gov (United States)

    Armas, Isabel; Pogrebnyak, Natalia; Raskin, Ilya

    2017-01-01

    Successful biotechnological improvement of crop plants requires a reliable and efficient in vitro regeneration system. Lettuce (Lactuca sativa L.), one the most important vegetable crops worldwide, is strongly genotype-dependent in terms of regeneration capacity, limiting the potential for biotechnological improvement of cultivars which show recalcitrance under currently available protocols. The effect of different nutrient sources, plant hormone combinations and activated charcoal supplementation on shoot induction efficiency was evaluated on the cultivar 'RSL NFR', which had previously shown poor regeneration efficiency. Multiple shoot organogenesis from cotyledon explants was recorded at the highest frequency and speed on Murashige and Skoog regeneration medium supplemented with 200 mg/l of activated charcoal, 3% sucrose, 10 mg/l benzylaminopurine and 0.5 mg/l naphthaleneacetic acid, which induced shoots through direct regeneration in 90.8 ± 7.9% of explants. High shoot induction efficiency was also observed, albeit not quantified, when using this medium on some other cultivars. This activated charcoal-containing regeneration medium might offer a rapid and efficient option for direct shoot induction in some lettuce genotypes that do not respond well to common lettuce regeneration protocols. This is also the first report of the effect of activated charcoal in lettuce tissue culture.

  2. Transfer of E. coli gutD gene into maize and regeneration of salt-tolerant transgenic plants

    Institute of Scientific and Technical Information of China (English)

    刘岩; 王国英; 刘俊君; 彭学贤; 谢友菊; 戴景瑞; 郭世伟; 张福锁

    1999-01-01

    GutD gene, encoding a key enzyme (glucitol-6-phosphate dehydrogenase) of sugar alcohol metabolic pathway in E. coli, was transferred into maize. Results of Southern and Western blotting analysis certified that this gene had integrated and been expressed in transgenic maize plants and their progeny. The synthesis and accumulation of sorbitol were detected in transgenic maize plants and a preliminary nutrient solution culture experiment showed that gutD transgenic maize plants had an increased tolerance to salt stress compared with nontransgenic ones.

  3. Abiotic stress leads to somatic and heritable changes in homologous recombination frequency, point mutation frequency and microsatellite stability in Arabidopsis plants

    Energy Technology Data Exchange (ETDEWEB)

    Yao Youli, E-mail: youli.yao@uleth.ca [Department of Biological Sciences, University of Lethbridge, Lethbridge, T1K 3M4 Alberta (Canada); Kovalchuk, Igor, E-mail: igor.kovalchuk@uleth.ca [Department of Biological Sciences, University of Lethbridge, Lethbridge, T1K 3M4 Alberta (Canada)

    2011-02-10

    In earlier studies, we showed that abiotic stresses, such as ionizing radiation, heavy metals, temperature and water, trigger an increase in homologous recombination frequency (HRF). We also demonstrated that many of these stresses led to inheritance of high-frequency homologous recombination, HRF. Although an increase in recombination frequency is an important indicator of genome rearrangements, it only represents a minor portion of possible stress-induced mutations. Here, we analyzed the influence of heat, cold, drought, flood and UVC abiotic stresses on two major types of mutations in the genome, point mutations and small deletions/insertions. We used two transgenic lines of Arabidopsis thaliana, one allowing an analysis of reversions in a stop codon-containing inactivated {beta}-glucuronidase transgene and another one allowing an analysis of repeat stability in a microsatellite-interrupted {beta}-glucuronidase transgene. The transgenic Arabidopsis line carrying the {beta}-glucuronidase-based homologous recombination substrate was used as a positive control. We showed that the majority of stresses increased the frequency of point mutations, homologous recombination and microsatellite instability in somatic cells, with the frequency of homologous recombination being affected the most. The analysis of transgenerational changes showed an increase in HRF to be the most prominent effect observed in progeny. Significant changes in recombination frequency were observed upon exposure to all types of stress except drought, whereas changes in microsatellite instability were observed upon exposure to UVC, heat and cold. The frequency of point mutations in the progeny of stress-exposed plants was the least affected; an increase in mutation frequency was observed only in the progeny of plants exposed to UVC. We thus conclude that transgenerational changes in genome stability in response to stress primarily involve an increase in recombination frequency.

  4. Abiotic stress leads to somatic and heritable changes in homologous recombination frequency, point mutation frequency and microsatellite stability in Arabidopsis plants.

    Science.gov (United States)

    Yao, Youli; Kovalchuk, Igor

    2011-02-10

    In earlier studies, we showed that abiotic stresses, such as ionizing radiation, heavy metals, temperature and water, trigger an increase in homologous recombination frequency (HRF). We also demonstrated that many of these stresses led to inheritance of high-frequency homologous recombination, HRF. Although an increase in recombination frequency is an important indicator of genome rearrangements, it only represents a minor portion of possible stress-induced mutations. Here, we analyzed the influence of heat, cold, drought, flood and UVC abiotic stresses on two major types of mutations in the genome, point mutations and small deletions/insertions. We used two transgenic lines of Arabidopsis thaliana, one allowing an analysis of reversions in a stop codon-containing inactivated β-glucuronidase transgene and another one allowing an analysis of repeat stability in a microsatellite-interrupted β-glucuronidase transgene. The transgenic Arabidopsis line carrying the β-glucuronidase-based homologous recombination substrate was used as a positive control. We showed that the majority of stresses increased the frequency of point mutations, homologous recombination and microsatellite instability in somatic cells, with the frequency of homologous recombination being affected the most. The analysis of transgenerational changes showed an increase in HRF to be the most prominent effect observed in progeny. Significant changes in recombination frequency were observed upon exposure to all types of stress except drought, whereas changes in microsatellite instability were observed upon exposure to UVC, heat and cold. The frequency of point mutations in the progeny of stress-exposed plants was the least affected; an increase in mutation frequency was observed only in the progeny of plants exposed to UVC. We thus conclude that transgenerational changes in genome stability in response to stress primarily involve an increase in recombination frequency.

  5. Species and rotation frequency influence soil nitrogen in simplified tropical plant communities.

    Science.gov (United States)

    Ewel, John J

    2006-04-01

    Among the many factors that potentially influence the rate at which nitrogen (N) becomes available to plants in terrestrial ecosystems are the identity and diversity of species composition, frequency of disturbance or stand turnover, and time. Replicated suites of investigator-designed communities afforded an opportunity to examine the effects of those factors on net N mineralization over a 12-year period. The communities consisted of large-stature perennial plants, comprising three tree species (Hyeronima alchorneoides, Cedrela odorata, and Cordia alliodora), a palm (Euterpe oleracea), and a large, perennial herb (Heliconia imbricata). Trees were grown in monoculture and in combination with the other two life-forms; tree monocultures were subjected to rotations of one or four years, or like the three-life-form systems, left uncut. The work was conducted on fertile soil in the humid lowlands of Costa Rica, a site with few abiotic constraints to plant growth. Rates of net N mineralization and nitrification were high, typically in the range of 0.2-0.8 microg x g(1) x d(-1), with net nitrification slightly higher than net mineralization, indicating preferential uptake of ammonium (NH4+) by plants and microbes. Net rates of N mineralization were about 30% lower in stands of one of the three tree species, Hyeronima, than in stands of the other two. Contrary to expectations, short-rotation management (one or four years) resulted in higher net rates of N mineralization than in uncut stands, whether the latter were composed of a single tree species or a combination of life-forms. Neither additional species richness nor replenishment of leached N augmented mineralization rates. The net rate at which N was supplied tended to be lowest in stands where demand for N was highest. Careful choice of species, coupled with low frequency of disturbance, can lead to maintenance of N within biomass and steady rates of within-system circulation, whereas pulses, whether caused by cutting

  6. Arsenic in soils and plants of woodland regenerated on an arsenic-contaminated substrate. A sustainable natural remediation?

    Energy Technology Data Exchange (ETDEWEB)

    Madejon, Paula; Lepp, Nicholas W. [School of Biological and Earth Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF (United Kingdom)

    2007-07-01

    Plant As accumulation at three As-polluted sites where spontaneous re-vegetation has taken place is examined. Each site had a different source of soil As (coal fly ash, LeBlanc process waste, canal dredging). Plant analysis indicates that soil-plant As transfer is poor at each site. Any mobile As is retained in root tissues, with little transfer to shoots. Bryophytes, pteridophytes, herbaceous and woody plants sampled at each site predominantly showed As concentrations of < 3 mg kg{sup -} {sup 1} dry wt, whilst total soil As ranged between 50 and 220 mg kg{sup -} {sup 1} dry wt. Risk associated with food chain transfer at these sites is low when compared to other routes such as direct ingestion/inhalation of As-contaminated particulates re-entrained from an unvegetated or unstable substrate. (author)

  7. Solasodine accumulation in regenerated plants of Solanum torvum Sw Acúmulo de solasodina em plantas micropropagadas de Solanum torvum Sw

    Directory of Open Access Journals (Sweden)

    C.B Moreira

    2010-03-01

    Full Text Available A nodal segment culture was developed in order to assess Solanum torvum Sw. regeneration and solasodine levels. The influence of auxins (indoleacetic acid, 1-Naphthaleneacetic acid and benzyl adenine on S. torvum growth in micropropagation was investigated. A nodal segment culture was initiated with seeds germinated in MS basal medium added of GA3 and grown in different concentrations of IAA, IAA + BAP and NAA + BAP. Sixty-day-old plants from the in vitro culture were collected, frozen and lyophilized; then, the methyl orange method was used to quantify solasodine for the spectrophotometric assay. The best results regarding plant regeneration and solasodine accumulation were obtained by using the MS basal medium without addition of plant growth regulators; however, there was great production of calluses presenting friable bases. Based on these results, cell cultures can be initiated from such calluses with application of other auxins and cytokinins to enhance solasodine production, besides different elicitors, light intensities and sucrose concentrations.A regeneração de Solanum torvum e a avaliação do conteúdo de solasodina foram os objetivos de cultura de segmentos nodais. A influência de auxinas (ácido 3-indolacético, ácido naftalenoacético e de 6-benzilaminopurina no crescimento de S. torvum na micropropagação foi investigado. Cultura de segmentos nodais foi iniciada por sementes germinadas em meio básico MS acrescido de GA3 e cultivadas em diferentes concentrações de AIA, AIA + BAP e ANA + BAP. Plantas da cultura in vitro com 60 dias foram coletadas, congeladas e liofilizadas e o método de alaranjado de metila foi utilizado para quantificação de solasodina para o ensaio espectrofotométrico. Os melhores resultados para regeneração vegetal e acúmulo de solasodina foram alcançados no meio MS sem adição de reguladores de crescimento havendo, porém grande produção de calos de base friáveis. Esses resultados mostram

  8. 曼陀罗种子萌发及植株再生%Seed germination and plant regeneration of Datura stramonium

    Institute of Scientific and Technical Information of China (English)

    张鸿; 张显强; 罗正伟; 谌金吾; 孙敏

    2012-01-01

    Objective To optimize the conditions for the seed germination and plant regeneration of Datura stramonium. Methods The seeds were treated by GA3 at different concentration for various durations, the germination percentage and germination trend of seeds were determined, and the effects of different hormones and media on the plant regeneration were investigated by orthogonal design. Results The seeds treated by GA3 (60 mg/L) for 10 h had the highest germination percentage (73.33%); The leaves had the highest survival rate (70.59%) when sterilized in 75% ethyl alcohol for 15 s then 0.1% HgCl2 for 3 min; The optimal medium for callus induction of leaves was MS + 0.5 mg/L 6-BA + 0.1 mg/L NAA, with the inductivity of 92.5%; The optimal medium for callus induction of clustered buds was MS + 2.0 mg/L 6-BA +0.1 mg/L NAA, with the inductivity of 94.50%; The rooting was radicated in hormone free MS medium and grew well after 15 d, and the survival rate of planting is over 95%. Conclusion The seeds of A stramonium germinate faster after being treated by GA3, and high efficient steriled plant regeneration system for D. stramonium is established by the "two-step method".%目的 探索曼陀罗种子萌发及组织培养条件的优化.方法 利用不同质量浓度GA3及不同处理时间的曼陀罗种子,测定其发芽率和发芽势;采用正交设计法探讨不同植物激素配比及培养基对曼陀罗再生体系建立的影响.结果 种子用60mg/L GA3浸泡10h后发芽率最高,达到73.33%;叶片用75%乙醇消毒15s后用0.1% HgCl2处理3 min时成活率最高,为70.59%;以叶片为外植体诱导出愈伤组织的最佳培养基为MS+0.5 mg/L 6-BA+0.1 mg/L NAA,诱导率达92.5%;丛生芽诱导的适宜培养基为MS+2.0 mg/L 6-BA+0.1 mg/L NAA,诱导率达到94.50%;生根为不加激素的MS培养基,15d后根系粗壮,移栽成活率达90%以上.结论 使用GA3促使曼陀罗种子快速萌发,用“两步法”建立了曼陀罗高效无菌再生体系.

  9. Tissue culture and plant regeneration of Ardisia crenata%朱砂根的组织培养与植株再生

    Institute of Scientific and Technical Information of China (English)

    马明东; 刘均利; 蒲尚饶

    2009-01-01

    目的:研究药用植物朱砂根组培快繁技术,为其产业化生产提供科学依据.方法:考察不同基本培养基、植物激素、添加物等对腋芽诱导、增殖及植株再生的影响.结果:以朱砂根带芽茎段为外植体,初代培养腋芽诱导的最佳培养基为MS+6-BA 0.5 mg·L~(-1)+NAA 0.1 mg·L~(-1).腋芽增殖的最佳培养基配方为MS+6-BA 2.0 mg·L~(-1)+NAA 0.1 mg·L~(-1)+KT 0.5 mg·L~(-1).生根培养基为1/2MS+IBA 0.2 mg·L~(-1);添加0.2%的活性炭可明显促进根的生长,提高生根率、生根数.最有利于朱砂根无菌苗移栽存活的基质类型为河沙.珍珠岩-蛭石(1:1:1),或蛭石.珍珠岩(1:1),成活率在80%以上.结论:通过腋芽增殖快繁育苗技术可获得完整植株,达到快速繁殖的目的.%Objective: Our research studied the fast-breeding technology of Ardisia crenata sims by using tissue culture and provided the scientific foundation for industry production. Method: The effects of axillary buds and plant regeneration of different basic medium, hormones and additives on induction and multiplication were studied. Result: The best culture medium for the induction of axillary buds, which took the stems of A. crenate were as explants, was MS + 6-BA 0. 5 mg · L~(-1) + NAA 0. 1 mg · L~(-1), and the best medium for multiplication was MS + 6-BA 2. 0 mg · L~(-1) + NAA 0. 1 mg · L~(-1) + KT 0. 5 mg · L~(-1), the best medium for roots generation was 1/2MS + IBA 0. 2 mg · L~(-1). We also found that the roots'generation, roots rate and mean number of roots can be promoted by adding 0. 2% Ac, and the most suitable ground substance was river sand-perlite-vermiculite (1: 1:1 ) or perlite-vermiculite (1:1 ).With axillary buds and plant regeneration methode, more than 80% A. crenata sims could be regenerated integratedly. Conclusion:A. crenata sims can be regenerated integratedly and breeded fast by using axillary bud proliferation technology.

  10. Functional pleiotropy and mating system evolution in plants: frequency-independent mating.

    Science.gov (United States)

    Jordan, Crispin Y; Otto, Sarah P

    2012-04-01

    Mutations that alter the morphology of floral displays (e.g., flower size) or plant development can change multiple functions simultaneously, such as pollen export and selfing rate. Given the effect of these various traits on fitness, pleiotropy may alter the evolution of both mating systems and floral displays, two characters with high diversity among angiosperms. The influence of viability selection on mating system evolution has not been studied theoretically. We model plant mating system evolution when a single locus simultaneously affects the selfing rate, pollen export, and viability. We assume frequency-independent mating, so our model characterizes prior selfing. Pleiotropy between increased viability and selfing rate reduces opportunities for the evolution of pure outcrossing, can favor complete selfing despite high inbreeding depression, and notably, can cause the evolution of mixed mating despite very high inbreeding depression. These results highlight the importance of pleiotropy for mating system evolution and suggest that selection by nonpollinating agents may help explain mixed mating, particularly in species with very high inbreeding depression. © 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.

  11. Pneumatic hydrodynamics influence transplastomic protein yields and biological responses during in vitro shoot regeneration of Nicotiana tabacum callus: Implications for bioprocess routes to plant-made biopharmaceuticals.

    Science.gov (United States)

    Barretto, Sherwin S; Michoux, Franck; Hellgardt, Klaus; Nixon, Peter J

    2017-01-15

    Transplastomic plants are capable of high-yield production of recombinant biopharmaceutical proteins. Plant tissue culture combines advantages of agricultural cultivation with the bioprocess consistency associated with suspension culture. Overexpression of recombinant proteins through regeneration of transplastomic Nicotiana tabacum shoots from callus tissue in RITA(®) temporary immersion bioreactors has been previously demonstrated. In this study we investigated the hydrodynamics of periodic pneumatic suspension of liquid medium during temporary immersion culture (4 min aeration every 8 h), and the impact on biological responses and transplastomic expression of fragment C of tetanus toxin (TetC). Biomass was grown under a range of aeration rates for 3, 20 and 40-day durations. Growth, mitochondrial activity (a viability indicator) and TetC protein yields were correlated against the hydrodynamic parameters, shear rate and energy dissipation rate (per kg of medium). A critical aeration rate of 440 ml min(-1) was identified, corresponding to a shear rate of 96.7 s(-1), pneumatic power input of 8.8 mW kg(-1) and initial 20-day pneumatic energy dissipation of 127 J kg(-1), at which significant reductions in biomass accumulation and mitochondrial activity were observed. There was an exponential decline in TetC yields with increasing aeration rates at 40 days, across the entire range of conditions tested. These observations have important implications for the optimisation and scale-up of transplastomic plant tissue culture bioprocesses for biopharmaceutical production.

  12. Natural regeneration processes in big sagebrush (Artemisia tridentata)

    Science.gov (United States)

    Schlaepfer, Daniel R.; Lauenroth, William K.; Bradford, John B.

    2014-01-01

    Big sagebrush, Artemisia tridentata Nuttall (Asteraceae), is the dominant plant species of large portions of semiarid western North America. However, much of historical big sagebrush vegetation has been removed or modified. Thus, regeneration is recognized as an important component for land management. Limited knowledge about key regeneration processes, however, represents an obstacle to identifying successful management practices and to gaining greater insight into the consequences of increasing disturbance frequency and global change. Therefore, our objective is to synthesize knowledge about natural big sagebrush regeneration. We identified and characterized the controls of big sagebrush seed production, germination, and establishment. The largest knowledge gaps and associated research needs include quiescence and dormancy of embryos and seedlings; variation in seed production and germination percentages; wet-thermal time model of germination; responses to frost events (including freezing/thawing of soils), CO2 concentration, and nutrients in combination with water availability; suitability of microsite vs. site conditions; competitive ability as well as seedling growth responses; and differences among subspecies and ecoregions. Potential impacts of climate change on big sagebrush regeneration could include that temperature increases may not have a large direct influence on regeneration due to the broad temperature optimum for regeneration, whereas indirect effects could include selection for populations with less stringent seed dormancy. Drier conditions will have direct negative effects on germination and seedling survival and could also lead to lighter seeds, which lowers germination success further. The short seed dispersal distance of big sagebrush may limit its tracking of suitable climate; whereas, the low competitive ability of big sagebrush seedlings may limit successful competition with species that track climate. An improved understanding of the

  13. Regeneração de plantas após fusão de protoplastos de tangelo 'Page' e toranja 'Lau Tau' Plant regeneration after protoplast fusion of 'Page' tangelo and 'Lau Tau' pummelo

    Directory of Open Access Journals (Sweden)

    Dayse Cristina de Carvalho

    2007-08-01

    Full Text Available Buscou-se a hibridação somática entre tangelo 'Page' e toranja 'Lau Tau' visando à produção de porta-enxerto semelhante à laranja-azeda, por esta espécie ser considerada um provável híbrido entre C. reticulata e C. grandis. Após isolamento, fusão e cultivo de protoplastos, obtiveram-se brotações que foram enxertadas in vitro, em laranja 'Hamlin'. Dezessete plantas foram aclimatizadas em casa de vegetação. A análise de citometria de fluxo confirmou a constituição diplóide dessas plantas. Marcadores moleculares RAPD das plantas regeneradas apresentaram padrão de bandas similar ao de tangelo 'Page'. Entretanto, todas as plantas apresentaram conformação fenotípica diferente dos genitores.This work aimed to produce somatic hybrid between 'Page' tangelo and 'Lau Tau' pummelo in an attempt to regenerate a similar rootstock to sour orange, because this species is considered a probable hybrid between C. reticulata and C. grandis. After protoplast isolation, fusion and culture regenerated shoots were in vitro grafted on 'Hamlin' sweet orange. Seventeen plants were acclimatized in a greenhouse. Citometric flow analyses revealed that all plants are diploid. RAPD molecular markers of regenerated plants had the same pattern as compared to 'Page' tangelo. However, all plants had phenotypic traits different from both genitors.

  14. AtTCTP2, an Arabidopsis thaliana homolog of Translationally Controlled Tumor Protein, enhances in vitro plant regeneration

    OpenAIRE

    Roberto eToscano-Morales; Beatriz eXoconostle-Cázares; José Luis eCabrera-Ponce; Jesús eHinojosa-Moya; Jorge Luis eRuiz-Salas; Valentin eGalván-Gordillo; Ramon Gerardo eGuevara-González; Roberto eRuiz-Medrano

    2015-01-01

    The Translationally Controlled Tumor Protein (TCTP) is a central regulator of cell proliferation and differentiation in animals, and probably also in plants. Arabidopsis harbors two TCTP genes, AtTCTP1 (At3g16640), which is an important mitotic regulator, and AtTCTP2 (At3g05540), which is considered a pseudogene. Nevertheless, we have obtained evidence suggesting that this gene is functional. Indeed, a T-DNA insertion mutant, SALK_045146, displays a lethal phenotype during early rosette stage...

  15. Effects of phytoestrogens and other plant-derived compounds on mesenchymal stem cells, bone maintenance and regeneration.

    Science.gov (United States)

    Schilling, Tatjana; Ebert, Regina; Raaijmakers, Nadja; Schütze, Norbert; Jakob, Franz

    2014-01-01

    Phytoestrogens and other plant-derived compounds and extracts have been developed for the treatment of menopause-related complaints and disorders, e.g. hot flushes and osteoporosis. Since estrogens have been discussed to enhance the risk for hormone-sensitive cancers, research activities try to find alternatives. Phytoestrogens like genistein and resveratrol as well as other plant-derived compounds are capable of substituting for estrogens to some extent. Their effects on mesenchymal stem cells and the tissues derived therefrom have been investigated in vitro and in preclinical settings. Besides their well-known estrogenic, i.e. mainly antiresorptive effects on bone via estrogen receptor (ER) signalling, they also directly or indirectly affect osteogenic and adipogenic pathways. As a novel mechanism, phytoestrogens and plant-derived saponins and flavonoids like kaempferol and xanthohumol have been described to reciprocally affect the osteogenic versus the adipogenic differentiation pathway. Both, ER-mediated and other pathways mediate a shift towards osteogenesis by inhibiting PPARγ and C/EBPα, the key adipogenic transcription factors (TFs), while stimulating the key osteogenic TFs Runx2 and Sp7. Besides ER signalling, the broad spectrum of molecular mechanisms supporting osteogenesis comprises the modulation of PPARγ, Wnt/β-catenin, and Sirt1 signalling, which inversely influence the transcription or transactivation of osteogenic versus adipogenic TFs. Preventing the age- and hormone deficiency-related shift towards adipogenesis without provoking adverse estrogenic effects represents a very promising strategy for treating bone loss and other metabolic diseases beyond bone. Research on plant-derived compounds will have to be pursued in vitro as well as in preclinical studies and controlled clinical trials in humans are urgently needed. This article is part of a Special Issue entitled 'Phytoestrogens'.

  16. RADIO FREQUENCY IDENTIFICATION DEVICES: EFFECTIVENESS IN IMPROVING SAFEGUARDS AT GAS-CENTRIFUGE URANIUM-ENRICHMENT PLANTS.

    Energy Technology Data Exchange (ETDEWEB)

    JOE,J.

    2007-07-08

    Recent advances in radio frequency identification devices (RFIDs) have engendered a growing interest among international safeguards experts. Potentially, RFIDs could reduce inspection work, viz. the number of inspections, number of samples, and duration of the visits, and thus improve the efficiency and effectiveness of international safeguards. This study systematically examined the applications of RFIDs for IAEA safeguards at large gas-centrifuge enrichment plants (GCEPs). These analyses are expected to help identify the requirements and desirable properties for RFIDs, to provide insights into which vulnerabilities matter most, and help formulate the required assurance tests. This work, specifically assesses the application of RFIDs for the ''Option 4'' safeguards approach, proposed by Bruce Moran, U. S. Nuclear Regulatory Commission (NRC), for large gas-centrifuge uranium-enrichment plants. The features of ''Option 4'' safeguards include placing RFIDs on all feed, product and tails (F/P/T) cylinders, along with WID readers in all FP/T stations and accountability scales. Other features of Moran's ''Option 4'' are Mailbox declarations, monitoring of load-cell-based weighing systems at the F/P/T stations and accountability scales, and continuous enrichment monitors. Relevant diversion paths were explored to evaluate how RFIDs improve the efficiency and effectiveness of safeguards. Additionally, the analysis addresses the use of RFIDs in conjunction with video monitoring and neutron detectors in a perimeter-monitoring approach to show that RFIDs can help to detect unidentified cylinders.

  17. Inertial Response of Wind Power Plants: A Comparison of Frequency-Based Inertial Control and Stepwise Inertial Control

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiao; Gao, Wenzhong; Wang, Jianhui; Yan, Shijie; Wu, Ziping; Yan, Weihang; Gevorgian, Vahan; Muljadi, Eduard; Kang, Moses; Hwang, Min; Kang, YongCheol

    2016-11-21

    The frequency regulation capability of a wind power plant plays an important role in enhancing frequency reliability especially in an isolated power system with high wind power penetration levels. A comparison of two types of inertial control methods, namely frequency-based inertial control (FBIC) and stepwise inertial control (SIC), is presented in this paper. Comprehensive case studies are carried out to reveal features of the different inertial control methods, simulated in a modified Western System Coordination Council (WSCC) nine-bus power grid using real-time digital simulator (RTDS) platform. The simulation results provide an insight into the inertial control methods under various scenarios.

  18. My Regeneration:

    DEFF Research Database (Denmark)

    Carter, Dale

    2016-01-01

    and cultural referents shows that it offers an index to the album. Using its frontier setting and a variety of sacred and secular myths, symbols and icons, ‘Heroes and Villains,’ like Smile as a whole, offers historically-informed visions of national decline, crisis and regeneration that are at once critical...

  19. Frequency Activated Fast Power Reserve for Wind Power Plant Delivered from Stored Kinetic Energy in the Wind Turbine Inertia

    DEFF Research Database (Denmark)

    Knüppel, Thyge; Thuring, P.; Kumar, S

    2011-01-01

    is proposed that delivers a short-term power reserve from the kinetic energy in the wind turbine (WT) inertia, while considering the inherent characteristics of a wind power plant. The aim is to contribute with a fast power reserve to stabilize the frequency drop during large and sudden production deficits...

  20. Effect of alternation of agar and agarose on the green plant differentiation frequency of calli from wild rice

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@ In vitro culture of wild rice was difficult. Recently, we found that high agarose concentration of different media could improve the green plant differentiation frequency of calli from wild rice. We tested the effectiveness of alternation of agar and agarose in different media.

  1. In-Born Radio Frequency Identification Devices for Safeguards Use at Gas-Centrifuge Enrichment Plants

    Energy Technology Data Exchange (ETDEWEB)

    Ward,R.; Rosenthal,M.

    2009-07-12

    Global expansion of nuclear power has made the need for improved safeguards measures at Gas Centrifuge Enrichment Plants (GCEPs) imperative. One technology under consideration for safeguards applications is Radio Frequency Identification Devices (RFIDs). RFIDs have the potential to increase IAEA inspector"s efficiency and effectiveness either by reducing the number of inspection visits necessary or by reducing inspection effort at those visits. This study assesses the use of RFIDs as an integral component of the "Option 4" safeguards approach developed by Bruce Moran, U.S. Nuclear Regulatory Commission (NRC), for a model GCEP [1]. A previous analysis of RFIDs was conducted by Jae Jo, Brookhaven National Laboratory (BNL), which evaluated the effectiveness of an RFID tag applied by the facility operator [2]. This paper presents a similar evaluation carried out in the framework of Jo’s paper, but it is predicated on the assumption that the RFID tag is applied by the manufacturer at the birth of the cylinder, rather than by the operator. Relevant diversion scenarios are examined to determine if RFIDs increase the effectiveness and/ or efficiency of safeguards in these scenarios. Conclusions on the benefits offered to inspectors by using in-born RFID tagging are presented.

  2. Estimated recurrence frequencies for initiating accident categories associated with the Clinch River Breeder Reactor Plant design

    Energy Technology Data Exchange (ETDEWEB)

    Copus, E R

    1982-04-01

    Estimated recurrence frequencies for each of twenty-five generic LMFBR initiating accident categories were quantified using the Clinch River Breeder Reactor Plant (CRBRP) design. These estimates were obtained using simplified systems fault trees and functional event tree models from the Accident Delineation Study Phase I Final Report coupled with order-of-magnitude estimates for the initiator-dependent failure probabilities of the individual CRBRP engineered safety systems. Twelve distinct protected accident categories where SCRAM is assumed to be successful are estimated to occur at a combined rate of 10/sup -3/ times per year while thirteen unprotected accident categories in which SCRAM fails are estimated to occur at a combined rate on the order of 10/sup -5/ times per year. These estimates are thought to be representative despite the fact that human performance factors, maintenance and repair, as well as input common cause uncertainties, were not treated explicitly. The overall results indicate that for the CRBRP design no single accident category appears to be dominant, nor can any be totally eliminated from further investigation in the areas of accident phenomenology for in-core events and post-accident phenomenology for containment.

  3. 芥蓝高频离体再生体系的建立%Establishment of high-frequency in vitro regeneration system of Chinese kale ( Brassica alboglabra Bailey)

    Institute of Scientific and Technical Information of China (English)

    唐君; 张蜀宁; 侯喜林; 王淑敏; 孙成振

    2011-01-01

    Based on three Chinese kale( Brassica alboglabra Bailey)varieties of' Sharp Leaf Chinses Kale' ,' Middle Flower Chinese Kale' and' Late-Flower Chinese Kale', we established a high frequency in vitro regeneration system through examining genotype, explant type,different hormones combinations and thidiazuron (TDZ)pretreatment on shoot regeneration effect.The results showed that the' Middle Flower Chinese Kale' held the most powerful regenerative capacity.The descending orders of regeneration rates from different types of explants were: hypocotyl, petiole with cotyledons, cotyledon;the optimum hormone combination of getting highfrequency shoot regeneration was 0.2 mg·L-1 naphthaleneacetic acid(NAA) and 6 mg·L-1 benzyladenine(6-BA).Hypocotyls with 0.5 mg·L-1 TDZ soaking 30 min pretreatment vaccinated medium containing 0.2 mg·L-1 NAA ,6 mg·L-1 6-BA ,8 g· L-1 agar+30 g· L-1 sucrose was suitable recipe for getting the highest rate of adventitious shoot regeneration,reaching 98.5%.%以'尖叶芥蓝'、'中花粗心芥蓝'和'迟花芥蓝'3个品种为材料,研究苯基噻二唑脲(TDZ)预处理、不同激素配比、基因型和外植体类型对不定芽再生的影响,建立芥蓝离体高频再生体系.结果表明:3个品种中,'中花粗心芥蓝'再生能力最强;不同外植体类型中再生率由大到小依次为:下胚轴、带柄子叶、子叶块;不定芽再生的最佳激素组合为0.2 mg·L-1NAA+6 mg·L-16-BA;以此激素组合为基础,下胚轴经0.5 mg·L-1TDZ浸泡30 min预处理接种在分化培养基(MS+0.2 mg·L-1NAA+6 mg·L-16-BA+8 g·L-1琼脂+30 g·L-1蔗糖)上不定芽再生率最高,达98.5%.

  4. Low Cost, High Capacity Regenerable Sorbent for Carbon Dioxide Capture from Existing Coal-fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan [TDA Research, Inc., Wheat Ridge, CO (United States); Jayaraman, Ambalavanan [TDA Research, Inc., Wheat Ridge, CO (United States); Dietz, Steven [TDA Research, Inc., Wheat Ridge, CO (United States)

    2016-03-03

    In this project TDA Research, Inc (TDA) has developed a new post combustion carbon capture technology based on a vacuum swing adsorption system that uses a steam purge and demonstrated its technical feasibility and economic viability in laboratory-scale tests and tests in actual coal derived flue gas. TDA uses an advanced physical adsorbent to selectively remove CO2 from the flue gas. The sorbent exhibits a much higher affinity for CO2 than N2, H2O or O2, enabling effective CO2 separation from the flue gas. We also carried out a detailed process design and analysis of the new system as part of both sub-critical and super-critical pulverized coal fired power plants. The new technology uses a low cost, high capacity adsorbent that selectively removes CO2 in the presence of moisture at the flue gas temperature without a need for significant cooling of the flue gas or moisture removal. The sorbent is based on a TDA proprietary mesoporous carbon that consists of surface functionalized groups that remove CO2 via physical adsorption. The high surface area and favorable porosity of the sorbent also provides a unique platform to introduce additional functionality, such as active groups to remove trace metals (e.g., Hg, As). In collaboration with the Advanced Power and Energy Program of the University of California, Irvine (UCI), TDA developed system simulation models using Aspen PlusTM simulation software to assess the economic viability of TDA’s VSA-based post-combustion carbon capture technology. The levelized cost of electricity including the TS&M costs for CO2 is calculated as $116.71/MWh and $113.76/MWh for TDA system integrated with sub-critical and super-critical pulverized coal fired power plants; much lower than the $153.03/MWhand $147.44/MWh calculated for the corresponding amine based systems. The cost of CO2 captured for TDA’s VSA based system is $38

  5. Interactive Effects of Growth Regulators, Carbon Sources, pH on Plant Regeneration and Assessment of Genetic Fidelity Using Single Primer Amplification Reaction (SPARS) Techniques in Withania somnifera L.

    Science.gov (United States)

    Fatima, Nigar; Ahmad, Naseem; Ahmad, Iqbal; Anis, Mohammad

    2015-09-01

    An improved and methodical in vitro shoot morphogenic approach through axillary bud multiplication was established in a drug yielding plant, Withania somnifera L. Effects of plant growth regulators [6-benzyladenine (BA), kinetin (Kin), 2-isopentenyladenine (2iP), and thidiazuron (TDZ)] either singly or in combination with α-napthalene acetic acid (NAA), indole-3-butyric acid (IBA), and indole-3-acetic acid (IAA) in Murashige and Skoog (MS) medium were tested. The highest regeneration frequency (90 %) with optimum number of shoots (32 ± 0.00)/explant were obtained on MS medium fortified with 2.5 μM 6-benzyladenine (BA) and 0.5 μM NAA and 30 g/l sucrose at pH 5.8. Among the tried TDZ concentrations, 0.5 μM resulted in maximum number of shoots (20.4 ± 0.40)/explant after 4 weeks of exposure. The proliferating shoot cultures established by repeated subculturing of the mother explants on the hormone-free medium produced the highest shoot number (29.4 ± 0.40) with shoot length (6.80 ± 0.12 cm)/explant at fourth subculture passage, which a decline in shoot proliferation was recorded. Different concentrations of NAA were tested for ex vitro rooting of microshoots. The maximum percentage of rooting 100 % with maximum roots (18.3 ± 0.1) was achieved in soilrite when basal portion of the microshoots were treated with 200 μM (NAA) for 15 min per shoot. The plantlets went through hardening phase in a growth chamber, prior to ex vitro transfer. The PCR-based single primer amplification reaction (SPAR) methods which include random amplified polymorphic DNA (RAPD) and direct amplification of minisatellite DNA (DAMD) markers has been used for assessment of genetic stability of micropropagated plantlets. No variation was observed in DNA fingerprinting patterns among the micropropagated and the donor plants illustrating their genetic uniformity.

  6. Frequency domain reflectometry NDE for aging cables in nuclear power plants

    Science.gov (United States)

    Glass, S. W.; Jones, A. M.; Fifield, L. S.; Hartman, T. S.

    2017-02-01

    Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. Although system tests verify cable function under normal loads, demonstration of some cable's ability to perform under exceptional loads associated with design-basis events is essential to assuring plant integrity. The cable's ability to perform safely over the initial 40-year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found in an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program that includes condition monitoring to justify cable performance under normal operation as well as accident conditions. A variety of tests are available to assess various aspects of electrical and mechanical cable performance, but none are suitable for all cable configurations nor does any single test confirm all features of interest. One particularly promising test that is beginning to be used more and more by utilities is frequency domain reflectometry (FDR). FDR is a nondestructive electrical inspection technique used to detect and localize faults in power and communication system conductors along the length of a cable from a single connection point. FDR detects discontinuities in the electrical impedance that arise due to cable splices or similar changes along the path of the conductor pair. In addition, FDR has the potential to provide sensitivity to insulation degradation by detecting small changes in impedance between the cable conductors being examined. The technique is also sensitive to cable bends, the particular lay of the cable in tray, proximity to other cable, and other factors that

  7. Control of Full-Scale Converter based Wind Power Plants for damping of low frequency system oscillations

    DEFF Research Database (Denmark)

    Adamczyk, Andrzej Grzegorz; Teodorescu, Remus; Rodriguez, Pedro

    2011-01-01

    to Full-Scale Converter based type. Moreover resemblance of such Wind Power Plant to modern FACTS devices is recognized and exploited. Paper discusses many aspect of damping controller design, including feedback signal selection and control effectiveness with respect to wind farm location. Analysis......Damping of low frequency power oscillations is one of essential aspects of maintaining power system stability. In literature can be found publications on damping capability of Doubly Fed Induction Generator based wind turbines. This paper extends discussion on Wind Power Plant damping capability...... and design is based on modal analysis, therefore matching modeling approach for wind power plant is proposed. Finally, performance of Wind Power Plant damping control is compared to a regular power system stabilizer installed on a synchronous generator....

  8. Periodontal regeneration.

    Science.gov (United States)

    Ivanovski, S

    2009-09-01

    The ultimate goal of periodontal therapy is the regeneration of the tissues destroyed as a result of periodontal disease. Currently, two clinical techniques, based on the principles of "guided tissue regeneration" (GTR) or utilization of the biologically active agent "enamel matrix derivative" (EMD), can be used for the regeneration of intrabony and Class II mandibular furcation periodontal defects. In cases where additional support and space-making requirements are necessary, both of these procedures can be combined with a bone replacement graft. There is no evidence that the combined use of GTR and EMD results in superior clinical results compared to the use of each material in isolation. Great variability in clinical outcomes has been reported in relation to the use of both EMD and GTR, and these procedures can be generally considered to be unpredictable. Careful case selection and treatment planning, including consideration of patient, tooth, site and surgical factors, is required in order to optimize the outcomes of treatment. There are limited data available for the clinical effectiveness of other biologically active molecules, such as growth factors and platelet concentrates, and although promising results have been reported, further clinical trials are required in order to confirm their effectiveness. Current active areas of research are centred on tissue engineering and gene therapy strategies which may result in more predictable regenerative outcomes in the future.

  9. Cell suspension culture and plant regeneration of a Brazilian plantain, cultivar Terra Cultura de células em suspensão e regeneração de plantas de bananeira cultivar Terra

    Directory of Open Access Journals (Sweden)

    Lucymeire Souza Morais-Lino

    2008-10-01

    Full Text Available The objective of this study was to establish cell suspension culture and plant regeneration via somatic embryogenesis of a Brazilian plantain, cultivar Terra Maranhão, AAB. Immature male flowers were used as explant source for generating highly embryogenic cultures 45 days after inoculation, which were used for establishment of cell suspension culture and multiplication of secondary somatic embryos. Five semisolid culture media were tested for differentiation, maturation, somatic embryos germination and for plant regeneration. An average of 558 plants per one milliliter of 5% SCV (settled cell volume were regenerated in the MS medium, with 11.4 µM indolacetic acid and 2.2 µM 6-benzylaminopurine. Regenerated plants showed a normal development, and no visible somaclonal variation was observed in vitro. It is possible to regenerate plants from cell suspensions of plantain banana cultivar Terra using MS medium supplemented with 11.4 µM of IAA and 2.2 µM of BAP.O objetivo deste trabalho foi estabelecer a cultura de células em suspensão e a regeneração de plantas via embriogênese somática de bananeira cultivar Terra Maranhão, AAB. Flores imaturas masculinas foram utilizadas como fonte de explante para obtenção de culturas altamente embriogênicas 45 dias após a inoculação, as quais foram utilizadas para o estabelecimento de suspensões celulares e multiplicação de embriões somáticos secundários. Cinco meios de cultura semi-sólidos foram testados para a diferenciação, maturação, germinação dos embriões somáticos e para a regeneração de plantas. A média de 558 plantas por mililitro de 5% SCV (volume de células sedimentadas foi regenerada, em meio MS com 11,4 µM de ácido indolacético e 2,2 µM de 6-benzilaminopurina. As plantas regeneradas apresentaram desenvolvimento normal, e não foi observada a ocorrência de variação somaclonal in vitro. É possível a regeneração de plantas a partir de células em suspens

  10. Large refinery and petrochemical plant furnaces and heaters : low frequency noise measurement and noise source order-ranking

    Energy Technology Data Exchange (ETDEWEB)

    Leslie Frank, HFP Acoustical Consultants Corp. Calgary AB

    2007-07-01

    Large furnaces and process heaters at refineries, gas plants, and petrochemical plants produce a low-frequency tonal noise from combustion roar. They can also produce mid-frequency broadband noise from induced draft fans. The common noise generating mechanisms are turbulence, flow instability, pressure drop, mechanical friction, and component vibration. Some of these energy facilities have multiple furnaces and heaters. As such, a noise source order-ranking assessment is typically performed to determine which plant equipment is responsible for the highest sound level contributions at nearby residence locations. The order-ranking is useful in determining which noise sources may require acoustical treatment to reduce the overall sound level at each residence. These results would form the basis for evaluating the effect of noise mitigating strategies for each source, and for estimating the associated costs for each noise control scenario. The noise model results can also be used to order-rank the equipment noise sources in terms of their frequency-dependant octave band. Experience has shown that large furnaces and heaters usually rank very high in terms of predominant contributors. The combustion roar noise generating mechanism is largely responsible for the predominant amount of acoustical energy. Although some degree of noise reduction can be achieved through burner design, it was shown that noise control engineering largely occurs at the furnace and heater manufacturing or plant retrofit level. This paper presented the results of one refinery with 19 older style furnaces and heaters. 1 tab., 7 figs.

  11. Regeneration of soybean via embryogenic suspension culture

    Directory of Open Access Journals (Sweden)

    Droste Annette

    2001-01-01

    Full Text Available In an attempt to establish an alternative plant regeneration system for soybean [Glycine max (L. Merrill] cultivars used in Brazilian breeding programs, ten genotypes were tested for their embryogenic potential. Cotyledons were removed as explants from immature seeds harvested from field-grown plants. After 45 days on induction medium, the number of responding cotyledons and the number of somatic embryos per immature cotyledon were evaluated. The percentage of explants that produced somatic embryos varied from 1 to 70% among cultivars. The average number of somatic embryos produced per cotyledon pair ranged from 0.01 to 10.3 with a mean of 3.4. Suspension cultures were initiated with three Agrobacterium tumefaciens susceptible cultivars. Suspensions were successfully developed from Bragg and IAS5 cultivars. The packed cell volume, in one-month growth, increased 8.1 fold for Bragg and 3.5 fold for IAS5 and the fresh weight increased 6.6 and 2.8 fold, respectively. The cultivars differed for the analysed parameters. All tissue from each cultivar was transferred to the maturation medium and subsequently to the germination medium. The germination frequency was 45.7 and 54.9% for Bragg and IAS5, respectively. Plants were gradually exposed to ambient humidity over one week and then planted in soil. All plants yielded seeds in the greenhouse.

  12. Callus induction and plant regeneration of Oncidium‘Gower Ramsey’ by means of protocorm-like body culture%文心兰类原球茎的愈伤组织诱导及其植株再生

    Institute of Scientific and Technical Information of China (English)

    黄霞; 卢禹

    2016-01-01

    该研究首次以文心兰的类原球茎( protocorm-like bodies, PLBs)为外植体进行愈伤组织诱导及其植株再生培养,并分析了不同浓度的TDZ和2,4-D配比对愈伤组织增殖的影响。结果表明:以1/2MS为基本培养基,添加1 mg.L-1 TDZ与3 mg.L-12,4-D,从接种的 PLBs上可以诱导出乳白色的、较疏松的愈伤组织,诱导频率达到100%。愈伤组织继代培养时,在2,4-D浓度为0.5~2.0 mg.L-1的范围内,其增殖主要受TDZ浓度的影响,TDZ浓度从1.0 mg.L-1降低到0.5 mg.L-1,愈伤组织鲜重增殖倍数显著增加,由最低的4.50倍增加到最高的6.04倍。愈伤组织增殖的最适培养基为1/2MS +0.5 mg.L-1 TDZ +1.0 mg.L-12,4-D。将在最适愈伤组织增殖培养基上继代培养约1个月的愈伤组织转移到T2培养基(3.5 g.L-1花宝1号+20 g.L-1红薯+25 g.L-1香蕉+1 g.L-1 tryptone +20 g.L-1蔗糖+3.5 g.L-1 phytagel)上,黑暗培养1个月后,每克鲜重的愈伤组织约诱导出1328.67个PLBs。将诱导出的PLBs转移到新鲜的T2培养基上光照培养1个月,萌发率为90.12%。而将小植株转移到添加1 g.L-1活性炭的1/2MS培养基上,成苗率达到100%。该研究结果成功建立了文心兰的高频愈伤组织诱导及其植株再生体系,为文心兰基因工程育种提供了一个高效、稳定的转化受体系统。%Oncidium ‘Gower Ramsey ’ is a species of orchid with high ornamental value and strong market competitiveness. Gene engineering breeding technology provides an effective way for the genetic improvement of ornamental plants. And callus is an ideal transformation receptor. Up to now, callus induction and plant regeneration of Onciudium have been successfully achieved using stem segment, root tip and shoot tip. But there are some shortcomings for these in vitro re-generation systems, such as low frequency and long period of callus induction, difficulty in maintaining embryogenic state of callus, etc. In this research, for

  13. Constitutive expression of the tzs gene from Agrobacterium tumefaciens virG mutant strains is responsible for improved transgenic plant regeneration in cotton meristem transformation.

    Science.gov (United States)

    Ye, Xudong; Chen, Yurong; Wan, Yuechun; Hong, Yun-Jeong; Ruebelt, Martin C; Gilbertson, Larry A

    2016-03-01

    KEY MESSAGE : virG mutant strains of a nopaline type of Agrobacterium tumefaciens increase the transformation frequency in cotton meristem transformation. Constitutive cytokinin expression from the tzs gene in the virG mutant strains is responsible for the improvement. Strains of Agrobacterium tumefaciens were tested for their ability to improve cotton meristem transformation frequency. Two disarmed A. tumefaciens nopaline strains with either a virGN54D constitutively active mutation or virGI77V hypersensitive induction mutation significantly increased the transformation frequency in a cotton meristem transformation system. The virG mutant strains resulted in greener explants after three days of co-culture in the presence of light, which could be attributed to a cytokinin effect of the mutants. A tzs knockout strain of virGI77V mutant showed more elongated, less green explants and decreased cotton transformation frequency, as compared to a wild type parental strain, suggesting that expression of the tzs gene is required for transformation frequency improvement in cotton meristem transformation. In vitro cytokinin levels in culture media were tenfold higher in the virGN54D strain, and approximately 30-fold higher in the virGI77V strain, in the absence of acetosyringone induction, compared to the wild type strain. The cytokinin level in the virGN54D strain is further increased upon acetosyringone induction, while the cytokinin level in the virGI77V mutant is decreased by induction, suggesting that different tzs gene expression regulation mechanisms are present in the two virG mutant strains. Based on these data, we suggest that the increased cytokinin levels play a major role in increasing Agrobacterium attachment and stimulating localized division of the attached plant cells.

  14. Impact of application of zinc oxide nanoparticles on callus induction, plant regeneration, element content and antioxidant enzyme activity in tomato (Solanum lycopersicum Mill. under salt stress

    Directory of Open Access Journals (Sweden)

    Alharby Hesham F.

    2016-01-01

    Full Text Available The properties of nanomaterials and their potential applications have been given considerable attention by researchers in various fields, especially agricultural biotechnology. However, not much has been done to evaluate the role or effect of zinc oxide nanoparticles (ZnO-NP in regulating physiological and biochemical processes in response to salt-induced stress. For this purpose, some callus growth traits, plant regeneration rate, mineral element (sodium, potassium, phosphorous and nitrogen contents and changes in the activity of superoxide dismutase (SOD and glutathione peroxidase (GPX in tissues of five tomato cultivars were investigated in a callus culture exposed to elevated concentrations of salt (3.0 and 6.0 g L-1NaCl, and in the presence of zinc oxide nanoparticles (15 and 30 mg L-1. The relative callus growth rate was inhibited by 3.0 g L-1 NaCl; this was increased dramatically at 6.0 g L-1. Increasing exposure to NaCl was associated with a significantly higher sodium content and SOD and GPX activities. Zinc oxide nanoparticles mitigated the effects of NaCl, and in this application of lower concentrations (15 mg L-1 was more effective than a higher concentration (30 mg L-1. This finding indicates that zinc oxide nanoparticles should be investigated further as a potential anti-stress agent in crop production. Different tomato cultivars showed different degrees of tolerance to salinity in the presence of ZnO-NP. The cultivars Edkawy, followed by Sandpoint, were less affected by salt stress than the cultivar Anna Aasa.

  15. Frequency Activated Fast Power Reserve for Wind Power Plant Delivered from Stored Kinetic Energy in the Wind Turbine Inertia

    DEFF Research Database (Denmark)

    Knüppel, Thyge; Thuring, P.; Kumar, S

    2011-01-01

    With increased penetration of converter interfaced generation, synchronous generators may start to be displaced to keep the overall power balance. As a consequence the resulting inertia in the system may decrease and make the power system more exposed to frequency excursions. Here, a control...... is proposed that delivers a short-term power reserve from the kinetic energy in the wind turbine (WT) inertia, while considering the inherent characteristics of a wind power plant. The aim is to contribute with a fast power reserve to stabilize the frequency drop during large and sudden production deficits...

  16. Adventitious shoot regeneration of Platanus acerifolia Willd.facilitated by Timentin, an antibiotic for suppression of Agrobacterium tumefaciens in genetic transformation

    Institute of Scientific and Technical Information of China (English)

    Li Zhi-neng; Liu Guo-feng; Fang Fang; Bao Man-zhu

    2007-01-01

    The effects of Timentin and cefotaxime (Cef) on shoot regeneration of the London plane tree (Platanus acerifolia Willd.) and their use for the suppression of Agrobacterium tumefaciens in Agrobacterium-mediated genetic transformation were compared.Shoot regeneration was significantly reduced on the media with Cef at concentrations from 100 to 500 mg·L-1. Timentin showed negative effect on plant regeneration at concentrations of 100 and 500 mg·L-1; however, 300 mg·L-1 Timentin was shown to facilitate shoot regeneration significantly and the regeneration frequency increased from 64% (control) to 88%. Effective suppression of A.tumefaciens could be obtained with 500 mg·L-1 Cef, but plant regeneration was completely inhibited at this level. The A. tumefaciens on infected P. acerifolia leaf tissues was visually undetectable after three subcultures on a medium with 300 mg·L-1 Timentin. Considering the effect of Cef and Timentin on plant regeneration and suppression of Agrobacteria, Timentin at 300 mg·L-1 is the preferred application in A. tumefaciens-mediated transformation of P.acerifolia.

  17. Haploid Plant Induction via in Vitro Gynogenesis and Plant Regeneration in Onion (Allium cepa L.)%离体雌核发育诱导洋葱单倍体与植株再生

    Institute of Scientific and Technical Information of China (English)

    刘冰江; 缪军; 霍雨猛; 杨妍妍; 徐坤; 吴雄

    2012-01-01

    以来自日本的3个中日照型洋葱(Allium cepa L.)杂交种的未开放花蕾为外植体材料,研究了2,4-D和6-BA浓度及配比对单倍体诱导培养的影响,以建立洋葱单倍体诱导技术体系。研究结果表明,含有1.5 mg · L^-1 2,4-D + 1.5 mg · L^-1 6-BA和2.0 mg · L^-1 2,4-D + 2.0 mg · L^-1 6-BA的B5培养基适于洋葱单倍体的诱导,诱导率最高达到4.00%。共获得了43枚雌核发育胚,雌核发育胚转移至不含激素的B5基本培养基中即可发育成完整植株,再生植株驯化移栽成活率达到100%。利用根尖染色体计数和流式细胞仪鉴定有42株是单倍体。%The flower buds of three intermediate-day hybrid cultivars of onion(Allium cepa L.)from Japanese seed company were cultured in vitro using B5 medium which supplied with 100 g · L-1 sucrose and 2,4-D and 6-BA. The suitable media for haploid induction of onion were B5 medium with 1.5 mg · L-1 2,4-D + 1.5 mg · L-1 6-BA and B5 medium with 2.0 mg · L-1 2,4-D + 2.0 mg · L-1 6-BA. The highest induction rate was 4.00%. Forty-three gynogenic embryos were obtained and each of them developed into the whole plant on the B5 medium with no any plant growth regulators. The regenerated plantlets were domesticated and transplanted in greenhouse. The survival rate was 100%. Ploidy analysis of the regenerants with chromosome counts of root tip cells and flow cytometry analysis of leaf tissue revealed that 42 of them are haploid.

  18. Screening of Brazilian soybean genotypes with high potential for somatic embryogenesis and plant regeneration Seleção de genótipos brasileiros de soja com alto potencial para embriogênese somática e regeneração de plantas

    Directory of Open Access Journals (Sweden)

    Annette Droste

    2010-07-01

    Full Text Available The aim of this work was to identify Brazilian soybean (Glycine max genotypes with potential to respond to in vitro culture stimuli for primary somatic embryo induction, secondary embryo proliferation and plant regeneration. Differences among eight tested cultivars were observed at each stage. Two cultivars, IAS-5 and BRSMG 68 Vencedora, were selected for the evaluation of the capacity for embryo differentiation and plant regeneration. These cultivars had high embryo induction frequencies, repetitive embryogenic proliferation, and low precocious embryo germination in the initial experiment. The effect of abscisic acid (ABA and charcoal addition on plant regeneration was investigated. The addition of ABA to proliferation medium and of ABA and activated charcoal to maturation medium increased embryo differentiation rates, which resulted in a higher number of regenerated plants. The BRSMG 68 Vencedora cultivar was found to have a high potential for embryo induction, embryo proliferation and plant regeneration. The potential of this cultivar for somatic embryogenesis was similar to that observed for cultivar IAS-5, which is currently used for soybean transformation in Brazil. BRSMG 68 Vencedora may be a good alternative genotype for soybean genetic engineering via somatic embryogenesis protocols.O objetivo deste trabalho foi identificar cultivares brasileiras de soja (Glycine max com capacidade de resposta aos estímulos da cultura in vitro para a indução de embriões somáticos primários, proliferação de embriões secundários e regeneração de plantas. Foram observadas diferenças para cada estádio entre as oito cultivares testadas. Foram selecionadas duas cultivares, 'IAS-5' e BRSMG 68 Vencedora, para avaliação do potencial dos embriões quanto à diferenciação e conversão em plantas. Essas cultivares tiveram altas taxas de indução, proliferação embriogênica repetitiva e baixa germinação precoce dos embriões, no experimento

  19. Cell Wall Regeneration by Protoplasts in the Weak Combined Magnetic Field

    Science.gov (United States)

    Nedukha, Olena; Bogatina, Nina; Kordyum, Elizabeth; Ovcharenko, Yu.; Vorobyeva, T.

    2008-06-01

    Role of gravity on growth of high plants has been studied for many years, but many questions on biogenesis of plant cell wall are investigated insufficiently, and require new experiments. We have studied regeneration of cell wall in the fused and separate protoplasts of tobacco and soyabean in the presence of the weak, alternating magnetic field that consisted of frequency of 32 Hz (for Ca2+ ; F=40 μT) or 75 Hz (for Mg2+; F=60 μT) in side μ-metal shield. We discovered that the combined magnetic field that was adjusted to the cyclotron frequency of Ca2+ or Mg2+ is changed the rate of cell wall regeneration. Light and confocal laser microscopy were used for the investigations.

  20. Shoot regeneration from GUS-transformed tomato (Lycopersicon esculentum) hairy root.

    Science.gov (United States)

    Moghaieb, Reda E A; Saneoka, Hirofumi; Fujita, Kounosuke

    2004-01-01

    To study the influence of genetic background on the transformation and regeneration of cultivated tomato plants, hairy root lines of tomato (Lycopersicon esculentum) were obtained by inoculating the hypocotyl explants of three tomato cultivars with the Agrobacterium rhizogenes strain DCAR-2, which harbors the pBI-121 binary vector. The Ri-T-DNA transformation into the plant DNA was confirmed by both of mikimopine and GUS assay analyses. The regeneration efficiency from hairy root explants was assessed. The data indicated that white embryonic calli were formed within two weeks in the presence of 2 mgl(-1) 2, 4-D plus 0.25 mgl(-1) kinetin. Adventitious shoots emerged from the embryonic callus in the presence of 1 mgl(-1) GA3 along with 0.5 mgl(-1) NAA. The regeneration frequency was higher in the cultivar UC-97, followed by Momotaro and then Edkawi. Molecular confirmation of the integration of the GUS gene into the hairy root-derived plants genomes was done via PCR using GUS-specific primers and also using Southern blotting analysis. Our data shows that regeneration is possible from hairy roots of the cultivated tomato and this system could be used to produce transgenic tomato plants expressing the genes present in Agrobacterium rhizogenes binary vectors.

  1. Regenerator seal

    Science.gov (United States)

    Davis, Leonard C.; Pacala, Theodore; Sippel, George R.

    1981-01-01

    A method for manufacturing a hot side regenerator cross arm seal assembly having a thermally stablilized wear coating with a substantially flat wear surface thereon to seal between low pressure and high pressure passages to and from the hot inboard side of a rotary regenerator matrix includes the steps of forming a flat cross arm substrate member of high nickel alloy steel; fixedly securing the side edges of the substrate member to a holding fixture with a concave surface thereacross to maintain the substrate member to a slightly bent configuration on the fixture surface between the opposite ends of the substrate member to produce prestress therein; applying coating layers on the substrate member including a wear coating of plasma sprayed nickel oxide/calcium flouride material to define a wear surface of slightly concave form across the restrained substrate member between the free ends thereon; and thereafter subjecting the substrate member and the coating thereon to a heat treatment of 1600.degree. F. for sixteen hours to produce heat stabilizing growth in the coating layers on the substrate member and to produce a thermally induced growth stress in the wear surface that substantially equalizes the prestress in the substrate whereby when the cross arm is removed from the fixture surface following the heat treatment step a wear face is formed on the cross arm assembly that will be substantially flat between the ends.

  2. Establishment of Genetic Transformation System for Miscanthus sacchariflorus and Obtaining of Its Transgenic Plants

    Institute of Scientific and Technical Information of China (English)

    Yi Zili(易自力); Zhou Puhua; Chu Chengcai; Li Xiang; Tian Wenzhong; Wang Li; Cao Shouyun; Tang Zuoshun

    2004-01-01

    The initiation and regeneration system for embryogenic callus of Miscanthus sacchariflrus is established at very high frequency. Potato proteinaseⅡ(pinⅡ) genes are introduced into the callus of Miscanthus sacchariflorus and some transgenic plants are obtained by the particle bombardment transformation system. PCR and Southern analysis show that target genes are integrated into the genome of these transgenic plants.

  3. Power Production Losses Study by Frequency Regulation in Weak-Grid-Connected Utility-Scale Photovoltaic Plants

    Directory of Open Access Journals (Sweden)

    Jesús Muñoz-Cruzado-Alba

    2016-04-01

    Full Text Available Nowadays, an increasing penetration of utility-scale photovoltaic plants (USPVPs leads to a change in dynamic and operational characteristics of the power distribution system. USPVPs must help to maintain the system stability and reliability while implementing minimum technical requirements (MTRs imposed by the utility grid. One of the most significant requirements is about frequency regulation (FR. Overall production of USPVPs is reduced significantly by applying FR curves, especially in weak grids with high rate of frequency faults. The introduction of a battery energy storage system (BESS reduces losses and improves the grid system reliability. Experimental frequency and irradiance data of several weak grids have been used to analyse USPVPs losses related to FR requirements and benefits from the introduction of a BESS. Moreover, its economic viability is showen without the need for any economic incentives.

  4. High Frequency Production of Doubled Haploid Rapeseed Plants by Direct Colchicine Treatment of Isolated Microspores%油菜小孢子秋水仙素直接处理增加纯合两倍体植株频率

    Institute of Scientific and Technical Information of China (English)

    周伟军; Per,H

    2000-01-01

    @@ Techniques for microspore culture of Brassica napus have been improved rapidly, and embryogenesis has been achieved in a wide range of genotypes. Plants regenerated from microspore-derived embryoids can be haploid, diploid or polyploid. From rapeseed microspore culture it is reported that 70%-90% of regenerated plants are haploid. The usual methods of chromosome doubling involve soaking roots (most common) or whole plants in a colchicine solution, or culturing plantlets in colchicine-containing medium in the greenhouse. Other alternatives are injecting colchicine into the secondary buds or applying colchicine-soaked cotton plugs to axillary buds.

  5. DNA-free genome editing in plants with preassembled CRISPR-Cas9 ribonucleoproteins.

    Science.gov (United States)

    Woo, Je Wook; Kim, Jungeun; Kwon, Soon Il; Corvalán, Claudia; Cho, Seung Woo; Kim, Hyeran; Kim, Sang-Gyu; Kim, Sang-Tae; Choe, Sunghwa; Kim, Jin-Soo

    2015-11-01

    Editing plant genomes without introducing foreign DNA into cells may alleviate regulatory concerns related to genetically modified plants. We transfected preassembled complexes of purified Cas9 protein and guide RNA into plant protoplasts of Arabidopsis thaliana, tobacco, lettuce and rice and achieved targeted mutagenesis in regenerated plants at frequencies of up to 46%. The targeted sites contained germline-transmissible small insertions or deletions that are indistinguishable from naturally occurring genetic variation.

  6. Embryoid Induction and Plant Regeneration of Petunia hybrida vilm by Its Anther Culture%矮牵牛花药培养胚状体诱导和植株再生

    Institute of Scientific and Technical Information of China (English)

    鲁娇娇; 张青; 王平; 侯超

    2013-01-01

    [目的]利用矮牵牛的花药培养诱导胚状体和再生植株.[方法]以7个品种矮牵牛的花药为材料,研究其胚状体及其再生植株的诱导方法.[结果]基因型和培养基成分对胚状体的诱导有重要影响;椰乳和活性炭对胚状体的发生及发育有促进作用;向改良MS培养基中添加0.01%活性炭可促进植株再生;最佳生根培养基为1/2MS+ IBA 0.2 mg/L.[结论]该研究为矮牵牛的大规模工业化生产奠定了基础.%[Objective] The paper was to induce the embryoid and regenerated plants of Petunia hybrida vilm by its anther culture. [Method] The induction methods of embryoid and regenerated plants were studied by using anther of 7 species of P. hybrida as materials. [Result] Genotype and medium composition had important effects on the induction of embryoid; coconut milk and activated carbon could promote the induction and development of embryoid; the modified MS medium supplemented with 0.01% activated charcoal could promote the regeneration of plants; the best rooting medium was 1/2MS + IBA 0.2 mg/L. [Conclusion] The study laid the foundation for the large-scale industrialization production of P. hybrida.

  7. In vitro plant regeneration from leaflet of peanut and its sensitivity to selection agent%花生胚小叶的离体再生及筛选压力选择

    Institute of Scientific and Technical Information of China (English)

    张月婷; 桂大萍; 黄家权; 雷永; 晏立英; 姜慧芳; 廖伯寿

    2012-01-01

    In order to develop a tissue culture system for peanut leaflet, the regeneration condition was optimized and plantlets sensitivity to selective agent was studied. Results showed significant differences on plant regeneration between different peanut genotypes, and Zhonghua 8 was more suitable for plant regeneration. MSB (MS mineral salt and B3 organic component) +6 - BA 4. 5mg/L + NAA Img/L + AgNO3 2mg/L was the best induction medium for Zhonghua 8 leaflet regeneration, and the induction time was 21 d. Glufosinate ammonium(PPT,20mg/L) could be used for selecting Zhonghua 8 regenerated plantlets, 300mg/L kanamycin (Km) could be used for selection of small seedlings and the concentration above 400mg/L would be more suitable for selection of larger seedling.%以花生胚小叶为外植体优化离体再生条件,通过对再生苗进行筛选,为外源基因的遗传转化提供实验依据.研究表明,不同基因型胚小叶的再生能力差异显著,在供试基因型中以中花8号不定芽诱导率和成苗率最高,且外植体状态最好.中花8号胚小叶再生的最佳诱导培养基为MSB(MS无机盐+B5有机成分)+6 - BA(4.5mg/L)+ NAA(1mg/L)+ AgNO3(2mg/L),最佳诱导培养时间为21d.对中花8号再生苗进行筛选浓度实验,草丁膦(PPT)为20mg/L时,可筛选出抗性苗;300mg/L的卡那霉素(Km)可用于较小幼苗筛选,而对较大幼苗则需将Km的浓度提高至400mg/L以上.

  8. A method for high-frequency intergeneric fusion of plant protoplasts.

    Science.gov (United States)

    Kao, K N; Michayluk, M R

    1974-12-01

    Protoplasts of Vicia hajastana Grossh. obtained from suspension-culture cells and Pisum sativum L. obtained from leaves adhered tightly to each other in concentrated solutions of high-molecular-weight polyethylene glycol (PEG). The adhesion occurred non-specifically between the free protoplasts from the same species as well as from the different species and genus. It was enhanced by enrichment of the PEG solution with calcium. Very few heteroplasmic fusions occurred during the period when the protoplasts were incubated in the PEG solution. However, many heterokaryons (up to 10%) were formed soon after the PEG solution was diluted out. The same phenomena were also observed in protoplasts from suspension-culture cells of Glycine max L. and from leaves of Hordeum vulgare L. Vicia and soybean protoplasts obtained from cultured cells regenerated cell walls and underwent sustained cell division after such treatment. Some Vicia-pea heterokaryons divided once. Over 10% of the soybean-barley hybrids divided in 7 days. Some divided 4-5 times and formed small clusters of cells in 10 days. The hybrids were recognizable because they contained chloroplasts from the leaf protoplast and exhibited morphological characters typical of the chlorophyll-less cells. None of the protoplasts from pea and barley leaves, either with or without PEG treatment, underwent cell division during the period of observation. The mechanism of adhesion and fusion of the protoplasts has been discussed.

  9. 蝴蝶兰叶片体细胞胚胎发生发育及其分化成苗的研究%Direct Somatic Embryogenesis on Leaf Explants of Phalaenopsis, Subsequent Development and Plant Regeneration

    Institute of Scientific and Technical Information of China (English)

    崔广荣; 廖玲玲; 刘跃成; 张子学

    2007-01-01

    蝴蝶兰幼叶离体培养直接诱导体细胞胚胎的发生并进一步发育成原球茎和分化成苗.体细胞胚胎发生起源于上表皮细胞或上表皮下方的叶肉细胞,为单细胞起源.单细胞原胚分裂形成多细胞原胚,历经球形胚、梨形胚、心形胚和子叶胚的发育过程,最终成为较大颗粒状的原球茎.较高浓度的苄基腺嘌呤(6-BA)和腺嘌呤硫酸盐(AdSO4)配合使用能有效诱导体细胞胚胎的发生,最高诱导率可达40%.适当降低6-BA和AdSO4浓度有利于原球茎分化成苗,但两者浓度过低苗的生长发育会受到影响.%Young leaf segments of an orchid (Phalaenopsis Tsuei Foa Lady) cultured in vitro produced clusters of somatic embryos directly from upper epidermis and mesophyll cells of leaf and wounded surfaces within 45 days. Embryonic cell produced multicellular proembryos by cell division. Multicellular proembryos were developing successively into globular embryoids, pear-shaped embryoids, heart-shaped embryoids, cotyledon-shaped embryoids and well-developed embryos----protocorm-like bodies (PLBs). High frequency of somatic embryogenesis was found on 1/2MS basal medium supplemented with a high dosage ofN6-benzyl adenine(6-BA, 4.0~8.0 mg/L) and adenine sulphate(AdSO4, 3.0~5.0 mg/L).The highest inducing rate was up to 40 per cent. The 6-BA and AdSO4 at lower concentrations had advantages in plant regeneration from PLBs while at too lower concentrations influenced the growth and development of the tube plantlets.

  10. [Promotion of transformation frequency of soybean (Glycine max L.) protoplasts using poly-L-ornithine].

    Science.gov (United States)

    Nan, X R; Wei, Z M

    1999-12-01

    The foreign Bt gene was transferred into protoplasts of soybean using PEG and PLO methods, respectively. The result indicated that the transformation frequency of PLO method was about 0.1% higher than PEG method. The PCR and Southern blotting analysis of the regeneration plants confirmed the integration of foreign gene into the genome of soybean.

  11. Influence of Wind Plant Ancillary Frequency Control on System Small Signal Stability

    DEFF Research Database (Denmark)

    Su, Chi; Chen, Zhe

    2012-01-01

    Since large-scale wind farms are increasingly connected to modern power grids, the transmission system operators put more requirements as part of the grid codes on the integration of wind farms. System frequency control which is normally provided by conventional synchronous generators becomes...... a common requirement to wind farms. This ancillary frequency control provided by wind farms could have some influence on the system small signal stability. This paper implements an ancillary frequency control strategy on a directdrive- full-convertor-based wind farm and studies its influence on the damping...... ratio values of the dominant oscillation modes within the connected power system. All the calculations and simulations are conducted in DIgSILENT PowerFactory 14.0....

  12. PLETHORA genes control regeneration by a two-step mechanism

    NARCIS (Netherlands)

    Kareem, Abdul; Durgaprasad, Kavya; Sugimoto, Kaoru; Du, Yujuan; Pulianmackal, Ajai J.; Trivedi, Zankhana B.; Abhayadev, Pazhoor V.; Pinon, Violaine; Meyerowitz, Elliot M.; Scheres, Ben; Prasad, Kalika

    2015-01-01

    Summary Regeneration, a remarkable example of developmental plasticity displayed by both plants and animals, involves successive developmental events driven in response to environmental cues. Despite decades of study on the ability of the plant tissues to regenerate a complete fertile shoot syste

  13. Applied and fundamental aspects of BABY BOOM-mediated regeneration

    NARCIS (Netherlands)

    Heidmann, I.A.

    2015-01-01

    Keywords: Somatic embryogenesis, Transcription factor, AINTEGUMENTA-LIKE, BABY BOOM, BBM, Sweet Pepper Transformation Title: Applied and Fundamental Aspects of BBM-mediated Regeneration Author: Iris Heidmann Catergories: Plant regeneration, Plant

  14. Damping of Low Frequency Power System Oscillations with Wind Power Plants

    DEFF Research Database (Denmark)

    Adamczyk, Andrzej Grzegorz

    the oscillations will last for considerable time, which may erroneously trigger the fault protection, or event might grow in amplitude leading eventually to the system collapse. On the other hand, the renewable resource based power plants have experienced tremendous growth in recent years. This trend is expected...

  15. Effects of Plant Cell Wall Matrix Polysaccharides on Bacterial Cellulose Structure Studied with Vibrational Sum Frequency Generation Spectroscopy and X-ray Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Park, Yong Bum; Lee, Christopher M; Kafle, Kabindra; Park, Sunkyu; Cosgrove, Daniel; Kim, Seong H

    2014-07-14

    The crystallinity, allomorph content, and mesoscale ordering of cellulose produced by Gluconacetobacter xylinus cultured with different plant cell wall matrix polysaccharides were studied with vibrational sum frequency generation (SFG) spectroscopy and X-ray diffraction (XRD).

  16. Ectopic expression of class 1 KNOX genes induce adventitious shoot regeneration and alter growth and development of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L).

    Science.gov (United States)

    Srinivasan, C; Liu, Zongrang; Scorza, Ralph

    2011-04-01

    Transgenic plants of tobacco (Nicotiana tabacum L) and European plum (Prunus domestica L) were produced by transforming with the apple class 1 KNOX genes (MdKN1 and MdKN2) or corn KNOX1 gene. Transgenic tobacco plants were regenerated in vitro from transformed leaf discs cultured in a medium lacking cytokinin. Ectopic expression of KNOX genes retarded shoot growth by suppressing elongation of internodes in transgenic tobacco plants. Expression of each of the three KNOX1 genes induced malformation and extensive lobbing in tobacco leaves. In situ regeneration of adventitious shoots was observed from leaves and roots of transgenic tobacco plants expressing each of the three KNOX genes. In vitro culture of leaf explants and internode sections excised from in vitro grown MdKN1 expressing tobacco shoots regenerated adventitious shoots on MS (Murashige and Skoog 1962) basal medium in the absence of exogenous cytokinin. Transgenic plum plants that expressed the MdKN2 or corn KNOX1 gene grew normally but MdKN1 caused a significant reduction in plant height, leaf shape and size and produced malformed curly leaves. A high frequency of adventitious shoot regeneration (96%) was observed in cultures of leaf explants excised from corn KNOX1-expressing transgenic plum shoots. In contrast to KNOX1-expressing tobacco, leaf and internode explants of corn KNOX1-expressing plum required synthetic cytokinin (thidiazuron) in the culture medium to induce adventitious shoot regeneration. The induction of high-frequency regeneration of adventitious shoots in vitro from leaves and stem internodal sections of plum through the ectopic expression of a KNOX1 gene is the first such report for a woody perennial fruit trees.

  17. Plant regeneration from proroplasts of alfalfa (Medicago sativa via somatic embryogenesis Regeneração de plantas a partir de protoplastos de alfafa (Medicago sativa via embriogênese somática

    Directory of Open Access Journals (Sweden)

    Mariza Monteiro

    2003-12-01

    Full Text Available Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this procedure is recommended for protoplast electroporation-mediated genetic transformation of alfalfa.A alfafa é uma das espécies mais freqüentemente estudadas do ponto de vista da produção de embriões somáticos derivados da cultura de tecidos. Neste trabalho, cinco cultivares de alfafa foram analisados com referência à capacidade de regenerar plantas a partir de culturas de protoplastos via embriogênese somática. Regeneração de plantas a partir de protoplastos isolados de folhas da cultivar Rangelander foi obtida usando-se um protocolo definido para embriogênese somática derivada de suspensões celulares de alfafa. Em função da sua alta eficiência, recomenda-se o uso deste procedimento para transformação genética de alfafa mediada por eletroporação de protoplastos.

  18. Efficient and reproducible in vitro regeneration of Solanum lycopersicum and assessment genetic uniformity using flow cytometry and SPAR methods

    Directory of Open Access Journals (Sweden)

    Abdulrahman A. Alatar

    2017-09-01

    Full Text Available In the present study, we develop an efficient and reproducible in vitro regeneration system for two cultivars viz., Jamila and Tomaland of Solanum lycopersicum L., an economically important vegetable crop throughout the world. Sterilization of seeds with 2.5% (v/v NaOCl was found to be most effective, about 97% of seeds germinated on cotton in magenta box moistened with sterile half strength (½Murashige and Skoog (MS medium. Regeneration efficiency of cotyledonary leaf (CL and cotyledonary node (CN explants derived from 08 days old aseptic seedling were assessed on MS medium supplemented with different concentrations of auxins and cytokinin. CL explants were found more responsive in comparison to CN in both the cultivars. Types of basal media were also assessed and found to have a significant effect on shoot regeneration. Highest regeneration frequency and maximum number of shoots were standardized from CL explants on MS medium supplied with 6-benzyl adenine (BA; 5.0 µM, indole-3-butyric acid (IBA; 2.5 µM and Kinetin (Kin; 10.0 µM. In vitro regenerated microshoots were rooted on ½MS medium containing 0.5 µM indole-3-butyric acid (IBA. Regenerated plantlets with well-developed roots and shoot system were successfully acclimated to ex vitro condition. Genetic uniformity of tissue culture raised plantlets was first time evaluated using flow cytometry and single primer amplification reaction (SPAR methods viz., DAMD and ISSR. No significant changes in ploidy level and nuclear DNA content profile were observed between in vitro propagated plants and normal plants of both the cultivars. Similarly, the SPAR analysis also revealed monomorphic banding patterns in regenerated plantlets of S. lycopersicum verifying their genetic uniformity and clonal fidelity. This efficient regeneration system can be used as a fast and reproducible method for genetic transformation of this important vegetable crop.

  19. Potential application of urea-derived herbicides as cytokinins in plant tissue culture.

    Science.gov (United States)

    Srinivasan, Malathi; Nachiappan, Vasanthi; Rajasekharan, Ram

    2006-12-01

    Various urea-derived herbicides and different cytokinin analogues were used to determine their effects on callusing response and shoot regenerating capacity of alfalfa (Medicago sativa L.) and Coleus (Coleus forskohlii Briq.). The herbicides monuron and diuron evoked profuse callusing response from Coleus leaf segments and alfalfa petiole explants on Murashige and Skoog medium. Shoot regeneration by monuron (2.0 mg/l) showed a maximum of 3 multiple shoots both in alfalfa and Coleus with a frequency of 92% and 75%, respectively. Whereas diuron (0.5 mg/l) showed a high frequency of shoot regeneration (89%)with a mean number of 5 shoots in alfalfa, in C.forskohlii, the frequency of regeneration was 90%with a mean number of 6 shoots. Diuron with two chloride groups in the phenyl ring showed significantly higher cytokinin-like activity than single chloride substitution monuron. This study demonstrates the potential use of monuron and diuron as cytokinins in plant tissue culture.

  20. Potential application of urea-derived herbicides as cytokinins in plant tissue culture

    Indian Academy of Sciences (India)

    Malathi Srinivasan; Vasanthi Nachiappan; Ram Rajasekharan

    2006-12-01

    Various urea-derived herbicides and different cytokinin analogues were used to determine their effects on callusing response and shoot regenerating capacity of alfalfa (Medicago sativa L.) and Coleus (Coleus forskohlii Briq.). The herbicides monuron and diuron evoked profuse callusing response from Coleus leaf segments and alfalfa petiole explants on Murashige and Skoog medium. Shoot regeneration by monuron (2.0 mg/l) showed a maximum of 3 multiple shoots both in alfalfa and Coleus with a frequency of 92% and 75%, respectively. Whereas diuron (0.5 mg/l) showed a high frequency of shoot regeneration (89%) with a mean number of 5 shoots in alfalfa, in C. forskohlii, the frequency of regeneration was 90% with a mean number of 6 shoots. Diuron with two chloride groups in the phenyl ring showed significantly higher cytokinin-like activity than single chloride substitution monuron. This study demonstrates the potential use of monuron and diuron as cytokinins in plant tissue culture.

  1. Improvements to LQGI/LTR Methodology for Plants with Lightly Damped or Low Frequency Poles

    Science.gov (United States)

    1992-12-01

    93 IV X-29 Aircraft Longitudinal MIMO Model Design .......................................... 94 4.1 Plant...nyrads= F reC..: I -4- 16,7 -- - --- Figure 28 Perturbed Complementary Sensitivity Curves of Three Designs 92 3.5 Summary In aircraft longitudinal control...designing LQG/LTR compensators with the stated methods. An A-4 aircraft longitudinal control is used for a SISO model; it has a pair of lightly damped

  2. 茎用芥菜细胞质雄性不育系子叶原生质体培养和高效植株再生%Efficient Plant Regeneration from Cotyledon-derived Protoplasts of Cytoplasmic Male-sterile Tuber Mustard (Brassica juncea Coss. var. tumida Tsen et Lee)

    Institute of Scientific and Technical Information of China (English)

    陈利萍; 张明方; 平田; 曹家树; 陈竹君

    2001-01-01

    利用茎用芥菜细胞质雄性不育系原生质体培养获得了再生植株,并研究了影响原生质体培养的因素.结果表明,子叶是茎用芥菜原生质体培养最佳的外植体,10 d苗龄的子叶原生质体在改良MS培养基上培养3 d后发生第1次细胞分裂,6 d后发生第2次分裂,3周后形成细胞团,5周后形成肉眼可见的小愈伤.培养基中缺少NAA或2,4-D都会降低愈伤组织的再生能力.在含一定浓度的NAA(0.25 mg/L)和2,4-D(0.25 mg/L)培养基上诱导的愈伤组织质地致密且有光泽,芽的分化能力高;在MS+BA l mg/L+NAA 0.2 mg/L的培养基上芽的分化频率高达近29%,再生芽在1/2MS+NAA0.1 mg/L培养基上生根,形成完整植株.%Plants of cytoplasmic male-sterile ( CMS )tuber mustard were regenerated from cotyledon-derived protoplasts. The factors affecting protoplast culture and plant regeneration were studied. Protoplasts isolated from 10-day-old seedlings of CMS tuber mustard showed cell division upon culture on modified MS me dium, and microcalli were produced at a high plating efficiency of nearly 16% after a 5-week culture. Various combinations and concentrations of growth regulators were added to the medium for the proliferation of microcalli, and to obtain regenerants from the calli.The results showed that NAA or 2,4-D was necessary for callus proliferation. The absence of NAA and 2,4-D resulted in production of the callus with low regenerative potential, and in the presence of NAA (0.25mg/L) and 2,4-D(0.25 mg/L), compact and bright calli were produced with high reproductive potential. Regenerated shoots were obtained at a frequency of nearly 29% when the compact and bright calli were selected and transferred at an early stage to the medium containing BA (1 mg/L) and NAA(0.2 rmg/L).All the regenerated shoots were rooted on 1/2MS medium with NAA 0.1 mg/L added.

  3. Variable frequency of plastid RNA editing among ferns and repeated loss of uridine-to-cytidine editing from vascular plants.

    Science.gov (United States)

    Guo, Wenhu; Grewe, Felix; Mower, Jeffrey P

    2015-01-01

    The distinct distribution and abundance of C-to-U and U-to-C RNA editing among land plants suggest that these two processes originated and evolve independently, but the paucity of information from several key lineages limits our understanding of their evolution. To examine the evolutionary diversity of RNA editing among ferns, we sequenced the plastid transcriptomes from two early diverging species, Ophioglossum californicum and Psilotum nudum. Using a relaxed automated approach to minimize false negatives combined with manual inspection to eliminate false positives, we identified 297 C-to-U and three U-to-C edit sites in the O. californicum plastid transcriptome but only 27 C-to-U and no U-to-C edit sites in the P. nudum plastid transcriptome. A broader comparison of editing content with the leptosporangiate fern Adiantum capillus-veneris and the hornwort Anthoceros formosae uncovered large variance in the abundance of plastid editing, indicating that the frequency and type of RNA editing is highly labile in ferns. Edit sites that increase protein conservation among species are more abundant and more efficiently edited than silent and non-conservative sites, suggesting that selection maintains functionally important editing. The absence of U-to-C editing from P. nudum plastid transcripts and other vascular plants demonstrates that U-to-C editing loss is a recurrent phenomenon in vascular plant evolution.

  4. Potential for CSO treatment with horizontal flow constructed wetlands: influence of hydraulic load, plant presence and loading frequency.

    Science.gov (United States)

    Pisoeiro, J; Galvão, A; Ferreira, F; Matos, J

    2016-10-01

    This study aimed at analysing the performance of horizontal subsurface flow constructed wetlands (CWs) to treat combined sewer overflow (CSO). Four horizontal subsurface flow CWs, organized in two groups (A and B) each with a planted (Phragmites australis) and a non-planted bed, were loaded with simulated CSO, with group B receiving twice the hydraulic load of group A. Beds were monitored for pH, dissolved oxygen, conductivity, redox potential, chemical oxygen demand (COD), total suspended solids (TSS) and enterococci. Porosity variations were also estimated. Monitoring was conducted during spring and wintertime, with regular and irregular loading frequencies. Results showed an average treatment efficiency of 90-100 % for TSS, 60-90 % for COD and 2-6 log for enterococci. Removal rates were especially relevant in the first 24 h for COD and TSS. TSS and enterococci removal did not exhibit the influence of macrophytes or the applied hydraulic load while COD's removal efficiency was lower in the higher load group and in planted beds.

  5. Failures during Load-Frequency Control Maneuvers in an Upgraded Hydropower Plant: Causes, Identification of Causes and Solution Proposals

    Directory of Open Access Journals (Sweden)

    Juan I. Pérez-Díaz

    2015-09-01

    Full Text Available The objective of this paper is to investigate the cause of several unexpected high amplitude oscillations that occurred in the surge tank water level of a real hydropower plant during secondary load-frequency control (LFC maneuvers, after the replacement of the turbine runner, and to propose solutions that allow the power plant to continue providing secondary LFC in a safe and reliable manner. For this purpose, a simulation model has been developed and calibrated from data gathered during several on-site tests. Two different solutions are proposed in order to cope with the observed problem: using a state-dependent load change rate limiter or modifying the hydro turbine governor gains; the turbine governor remains the same as before the runner replacement. The proposed solutions are tested against a set of realistic secondary LFC signals by means of simulations and compared to each other as a function of the probability that the surge tank water level descends below a minimum safe level and the quality of the secondary LFC response. The results presented in the paper demonstrate the validity of the methodology proposed to determine the state-dependent ramp limit, as well as its effectiveness to prevent the surge tank drawdown and to provide clear insight into the trade-off between response quality and power plant safety.

  6. 不同栽培处理下杂交水稻渝香203的再生性分析%Analysis of Regeneration of Hybrid Rice in Different Planting Treatments

    Institute of Scientific and Technical Information of China (English)

    张现伟; 李经勇; 唐永群; 姚雄

    2012-01-01

    Chongqing is one of the major grain yield areas of ratooning rice. Development of ratooning rice actively could help to ensure food security, improve rice structure, increase income of farmers and meet the needs of urban and rural people' s living, artificial transplanting, machine transplanting, throwing transplanting, direct seeding were mainly planting patterns. The trials of artificial transplanting manual harvest, artificial transplanting machine harvest, machine transplanting manual harvest, machine transplanting machine harvest, throwing transplanting manual harvest, direct seeding manual harvest were carried out to compare the regeneration, ratooning rice yield and rice-regeneration yield under six different planting patterns of hybrid rice. The results showed that artificial transplanting manual harvest, had obvious advantages in regeneration, ratooning yield, rice-regeneration on the total production, followed by Artificial transplanting machine harvest, machine transplanting manual harvest, machine transplanting machine harvest, throwing transplanting manual harvest, direct seeding manual harvest were the lowest of all.%重庆是再生稻的主产区之一,积极发展再生稻生产对确保粮食安全,改善稻米结构、增加农民收入、满足城乡人民生活需求等都具有重要意义.手工栽秧、机栽秧、抛秧、直播是目前水稻的主要栽培方式.本研究设置了人栽人收、人栽机收、机栽人收、机栽机收、抛秧人收、直播人收6个处理,比较了不同栽培处理下杂交水稻的再生性、再生稻产量及中稻-再生稻产量.结果表明:人栽人收在再生性、再生稻产量、中稻-再生稻总产上都具有明显的优势,依次为人栽机收、机栽人收、机栽机收、抛秧人收,直播人收处理下表现最低.

  7. Establishment and Optimization of the Regeneration System of Mature Embryos of Maize (Zea mays L.)

    Institute of Scientific and Technical Information of China (English)

    ZHAO Cheng-hao; ZHANG Li-jun; GE Chao; HU Kai

    2008-01-01

    A reliable system was developed for regeneration from mature embryos derived from callus of four maize inbred lines (Liao 7980,Dan 9818,Dan 340,and Dan 5026).The protocol was mainly based on a series of experiments involving the composition of culture medium.We found that 9 μM 2,4-dichlorophenoxyacetic acid in MS medium was optimum for the induction of callus.The induction frequency of primary calli was over 85% for four inbred lines tested.The addition of L-proline (12 mM) in subculture medium significantly promoted the formation of embryogenic callus but it did not significantly enhance growth rate of callus.Efficient shoot regeneration was obtained on regeneration medium containing 2.22 μM 6-benzylaminopurine in combinations with 4.64 μM Kinetin.Regenerated shoots were rooted on half-strength MS medium containing 2.85 μM indole-3-butyric acid.This plant regeneration system provides a foundation for genetic transformation of maize.

  8. Induction of Protocorm-like Bodies and Plant Regeneration of Pinellia ternate (Thunb.) Breit%半夏类原球茎的诱导及其植株再生研究

    Institute of Scientific and Technical Information of China (English)

    江艳华; 李艾莲; 陈彩霞; 崔思然; 赵锋

    2013-01-01

    :V). Protocorm-like bodies of Pinellia ternate could be induced in the suitable ratio of plant hormones from the right explant and high frequency regeneration system of Pinellia ternate could be established, which laid a foundation for Pinellia ternate germplasm resources conservation, gene engineering breeding, medicinal secondary metabolite production and so on.

  9. 中亚热带6种不同更新方式森林0-5mm根系直径频率分布%Diameter frequency distribution for 0-5mm roots in six mid-subtropical forests subject to different regeneration approaches

    Institute of Scientific and Technical Information of China (English)

    胡双成; 熊德成; 黄锦学; 王韦韦; 黄超超; 邓飞; 陈云玉; 陈光水

    2015-01-01

    运用土芯法研究福建省三明市6种不同更新方式林分(米槠天然林、米槠天然更新林、米槠人促更新林、米槠人工林、马尾松人工林、杉木人工林)根系的(直径≤5 mm)根长随直径分布特点。结果表明:0—5 mm直径根系的根长87%—98%集中于0—2 mm直径范围内,65%—88%集中于0—1 mm直径范围内。6种不同更新方式林分的根长直径分布均呈单峰型分布,且均可用对数正态分布累积函数进行较好的拟合,R2均达0.99以上。函数中拟合参数μ值和σ值的变化代表了不同林分细根在资源获取策略中的差异。拟合参数μ值和σ值之间具有很好的负相关,表明这两个参数呈现协同性变化,反映了细根资源获取策略中的权衡关系。随树种多样性的增加,μ值趋于更小而σ值更大,可能体现了树种间根系对养分和水分竞争的加剧;不同树种人工林μ值、σ值亦存在明显分异,反映了不同树种土壤资源利用策略的差异。结论表明对数正态分布累积函数可以很好地反映林分尺度的根系直径频率分布特点及根系资源利用策略。%Diameter is an important structural trait for root systems, with roots of different thickness havings different physiological functions. Root length is a significant index of root function, while root diameter frequency distribution provides useful information. Thus, studies on the characteristics of root diameter frequency distribution enhance our understanding about the root exploitation strategy for soil resources in different plant or forest systems, as well as the interaction between roots and the soil environment, allowing us to model projections. Using the soil coring method, the diameter frequency distribution characteristics of roots (≤5 mm in diameter) in six forests was determined using different regeneration approaches. The forests included:the nature forest of Castanopsis carlesii ( NF) , the secondary

  10. Frequency and quality of radiation monitoring of construction workers at two gaseous diffusion plants.

    Science.gov (United States)

    Bingham, Eula; Ringen, Knut; Dement, John; Cameron, Wilfrid; McGowan, William; Welch, Laura; Quinn, Patricia

    2006-09-01

    Construction workers were and are considered temporary workers at many construction sites. Since World War II, large numbers of construction workers were employed at U.S. Department of Energy nuclear weapons sites for periods ranging from a few days to over 30 years. These workers performed tasks during new construction and maintenance, repair, renovation, and demolition of existing facilities. Such tasks may involve emergency situations, and may entail opportunities for significant radiation exposures. This paper provides data from interviews with more than 750 construction workers at two gaseous diffusion plants (GDPs) at Paducah, Kentucky, and Portsmouth, Ohio regarding radiation monitoring practices. The aim was to determine the extent to which workers believed they were monitored during tasks involving potential radiation exposures. The adequacy of monitoring practices is important for two reasons: (a) Protecting workers from exposures: Construction workers were employed by sub-contractors, and may frequently been excluded from safety and health programs provided to permanent employees; and (b) Supporting claims for compensation: The Energy Employees Occupational Illness Compensation Program Act (EEOICPA) requires dose reconstruction of radiation exposures for most workers who file a claim regarding cancer. The use of monitoring data for radiation to qualify a worker means that there should be valid and complete monitoring during the work time at the various nuclear plants or workers may be unfairly denied compensation. The worker interviews from Paducah and Portsmouth were considered especially useful because these sites were designated as Special Exposure Cohorts (SECs) and the workers did not have to have a dose reconstruction to qualify for compensation for most cancers. Therefore, their responses were less likely to be affected by compensation concerns. Interview questions included asking for information regarding whether monitoring was performed, how

  11. Analysis of morphological traits of bird's foot trefoil plants cv. Bokor transformed with Agrobacterium rhizogenes

    Directory of Open Access Journals (Sweden)

    Nikolić Radomirka

    2005-01-01

    Full Text Available An efficient method for genetic transformation and shoot regeneration was achieved in bird's foot trefoil cv. Bokor using A. rhizogens. The transformed shoots were regenerated on hairy root segments in high frequency. After rooting and acclimation, transformed To plants were grown in experimental field. Analysis of morphological traits and chemical content in ten unintentionally chosen To bird's foot trefoil plants (genotypes no. 2 and no. 5 was performed. They were compared to those of control non-transformed plants. The traits as a number of stems per plant, length of internodes in longest stem, number of flowers per plant and plan high were very significant differed than the same traits in control plants, while there were no significant differences in the leaf area. No signs of the rol genes genotype and "T" phenotype were present. The transformed plants had significantly higher content of cellulose, while the protein and nitrogen contents of are in the range of control plants.

  12. Research on the Application of Plant Mixed Emulsified Asphalt Cold Regeneration Technology in the City Roads%厂拌乳化沥青冷再生技术在城市道路中的应用研究

    Institute of Scientific and Technical Information of China (English)

    马先锋

    2013-01-01

      文章通过对西安市厂拌乳化沥青冷再生配合比设计及西安市学院路厂拌乳化沥清冷再生工程实施方面的叙述,主要介绍了沥青路面厂拌乳化沥青冷再生技术在西安市城市道路中的应用研究。经过项目检测及分析,该技术适用于西安城市道路的修建与养护,可以充分循环利用旧路面回收材料(RAP),消纳建筑垃圾,减少大量新材料的使用和开山取石,具有显著的环保及资源循环利用效益,值得大力推广。%Through the introduction of plant mixed emulsified asphalt cold recycled mixture ratio design plant mixed emulsified asphalt cold regeneration project implementation of xueyuan road in Xi'an, this paper carried out research on the application of asphalt pavement plant mixed emulsified asphalt cold regeneration technology in city roads of Xi'an. After project detection and analysis, the technology can be applied in Xi'an urban road construction and maintenance, can make full use of old pavement recycled materials (RAP), digest construction waste, reduce the use of a large number of new materials, has significant environmental protection and resource recycling benefits, which is worth promoting.

  13. An improved protocol for efficient transformation and regeneration of diverse indica rice cultivars

    Directory of Open Access Journals (Sweden)

    Sahoo Khirod K

    2011-12-01

    Full Text Available Abstract Background Rice genome sequencing projects have generated remarkable amount of information about genes and genome architecture having tremendous potential to be utilized in both basic and applied research. Success in transgenics is paving the way for preparing a road map of functional genomics which is expected to correlate action of a gene to a trait in cellular and organismal context. However, the lack of a simple and efficient method for transformation and regeneration is a major constraint for such studies in this important cereal crop. Results In the present study, we have developed an easy, rapid and highly efficient transformation and regeneration protocol using mature seeds as explants and found its successful applicability to a choice of elite indica rice genotypes. We have optimized various steps of transformation and standardized different components of the regeneration medium including growth hormones and the gelling agent. The modified regeneration medium triggers production of large number of shoots from smaller number of calli and promotes their faster growth, hence significantly advantageous over the existing protocols where the regeneration step requires maximum time. Using this protocol, significantly higher transformation efficiency (up to 46% and regeneration frequency (up to 92% for the untransformed calli and 59% for the transformed calli were achieved for the four tested cultivars. We have used this protocol to produce hundreds of independent transgenic lines of different indica rice genotypes. Upon maturity, these transgenic lines were fertile thereby indicating that faster regeneration during tissue culture did not affect their reproductive potential. Conclusions This speedy, yet less labor-intensive, protocol overcomes major limitations associated with genetic manipulation in rice. Moreover, our protocol uses mature seeds as the explant, which can easily be obtained in quantity throughout the year and kept

  14. Development of Wind Power Generation Model with DFIG for Varying Wind Speed and Frequency Control for Wind Diesel Power Plant

    Directory of Open Access Journals (Sweden)

    Naresh Kumari

    2016-04-01

    Full Text Available The power generation with non-renewable energy sources has very harmful effects on the environment as well as these sources are depleting. On the other side the renewable energy sources are quite unpredictable source of power. The best trade-off is to use the combination of both kind of sources to make a hybrid system so that their individual power generation constraints can be overcome. The hybrid system taken for analysis in this work comprises of wind and diesel power generation systems. The complete modelling of the system has been done in MATLAB/SIMULINK environment. Doubly fed induction generator (DFIG is used for power generation in wind power system. The modelling has been done considering the changing wind speed and varying load conditions. The mathematical models of DFIG and diesel power generator have been used to develop the simulink model which can be used for analysis of various performances of the system like frequency response and power sharing between different sources with load variation .The generating margin of DFIG is also simulated for the frequency support during varying load conditions .The generating margin is created by the control of active power output from DFIG. Also as the power demand rises the generating margin of DFIG keeps the balance between the power generation and load. Proportional Integral controller has been used for diesel generator plant for frequency control. The controller gains have been optimized with Particle Swarm Optimization technique. The proper selection of controller gains and wind power reserve help to achieve the enhanced frequency response of the hybrid system.

  15. Damping of Low Frequency Power System Oscillations with Wind Power Plants

    DEFF Research Database (Denmark)

    Adamczyk, Andrzej Grzegorz

    In this thesis, the focus is given to low frequency power oscillations, which have been bothering power systems from their early days of existence. Among various types of oscillations the most bothering are inter-area oscillations, which have been involved in many blackout incidents that occurred...... oscillates against another coherent group located in another power system area, causing high power fluctuations on the tie-lines that interconnect the areas. The reason why inter-area oscillations compromise the power system stability is their poorly damped characteristic. It means that once triggered...... to continue. Especially wind power is seen as one of the main players on the energy markets of the future. However, to ensure seamless integration of high amount of non-synchronous generation, transmission system operators have specified a number of connection requirements. These requirements have pushed...

  16. Active magnetic regenerator

    Science.gov (United States)

    Barclay, John A.; Steyert, William A.

    1982-01-01

    The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

  17. Helping the Retina Regenerate

    Science.gov (United States)

    ... Briefs > Helping the retina regenerate Helping the retina regenerate NEI Audacious Goals Initiative report outlines strategies to replace or reprogram neurons in the retina News Brief 03/30/17 ...

  18. Study on Isolated Culture and Plant Regeneration of Agave sisalana H.11648%H.11648麻离体培养与植株再生的研究

    Institute of Scientific and Technical Information of China (English)

    张世清; 易克贤; 郑金龙; 陈河龙; 刘巧莲; 高建明

    2012-01-01

    以H.11648麻组培苗叶片为外植体,研究了不同生长调节剂对诱导愈伤、不定芽的分化、增殖及生根的影响.结果表明:在MS+0.5mg/L 2,4-D+4.0 mg/L 6 -BA +0.5mg/L NAA +3%蔗糖+0.23%植物凝胶(pH值5.8)培养基上诱导出愈伤组织为佳;在MS+ 3.0 mg/L 6 - BA +0.3 mg/L NAA培养基中,愈伤组织不定芽分化率最高;将小苗移栽至基质配比为土壤∶椰糠=2∶1的育苗盆中,成活率这96%.%Using the leaves of test - tubs seedlings of Agave sisalana H. 11648 as the explants, the effects of different growth regulating substances on the callus inducement, differentiation, proliferation and rooting of adventitious buds were researched. The results indicated that the highest callus inducement frequency was obtained on the medium MS +0.5 mg/L 2,4 -D +4.0 mg/L 6 -BA +0.5 mg/L NAA + 3% cane sugar + 0. 23% plant gelatum (pH 5. 8) , and the optimum medium for the differentiation of the adventitious buds from callus was MS +3.0 mg/L 6 - BA + 0. 3 mg/L NAA. The survival rate of the test - tube seenllings was 96% after they were transplanted into the nursery put with the substrate of soil + coconut bran (2: 1).

  19. Developmental and molecular biology of annelid regeneration: a comparative review of recent studies.

    Science.gov (United States)

    Özpolat, B Duygu; Bely, Alexandra E

    2016-10-01

    Studies of annelid regeneration have greatly increased in frequency in recent years, providing new insights into the developmental basis and evolution of regeneration. In this review, we summarize recent findings related to regeneration in annelids, focusing on molecular and developmental studies of epimorphic (blastema-based) regeneration, morphallactic (tissue-remodeling based) regeneration, and development and regeneration of putative stem cells of the posterior growth zone and germline. Regeneration is being investigated in a broad range of annelids spanning the phylum, and comparing findings among species reveals both widely conserved features that may be ancestral for the phylum as well as features that are variable across the group.

  20. 玉米自交系愈伤组织诱导及植株再生体系的建立%Establishment of Callus Induction and Plant Regeneration System of Maize Elite Inbred Lines

    Institute of Scientific and Technical Information of China (English)

    张颖君; 刘茜; 胡梦芸; 高慧敏; 李辉

    2011-01-01

    玉米的组织培养比较困难,其再生体系还不完善,建立骨干自交系稳定、高效的遗传转化体系是玉米转基因技术的必要前提。以玉米常用自交系齐319、478、502、黄C和7922不同大小(1.0、1.5和2.0 mm)的幼胚为外植体,探讨不同基因型、胚大小和植物生长调节剂浓度对幼胚再生的影响,从而建立玉米高频再生体系。结果表明:以1.5 mm大小的齐319幼胚为外植体,愈伤诱导率最高,达到了86.2%;1.5 mg/L的24-D有利于胚性愈伤的形成和胚性的保持;两步法分化培养可以提高愈伤组织分化、再生成苗。确定了玉米自交系齐319较适合的培养程序为:将1.5 mm大小的幼胚盾片向上接于诱导培养基(N6+24-D 1.5 mg/L+L-脯氨酸0.7 g/L+蔗糖30 g/L+琼脂粉8 g/L+硝酸银5μmol/L),在25℃下暗培养20 d;挑选胚性愈伤组织在温度25℃、暗培养条件下进行继代培养,继代培养基与诱导培养基相同,每14 d继代1次;将愈伤组织继代42 d后转移至分化培养基1(MS+肌醇100 mg/L+蔗糖60 g/L+gelrite 3 g/L),继续暗培养10 d左右,待愈伤组织形成象牙白色的块状物且有绿点出现时,将其转移到分化培养基2(MS+肌醇100 mg/L+蔗糖30 g/L+gelrite3 g/L)进行光培养,2~3 d即可分化出苗;待幼苗长到4~5 cm高时,移至生根培养基(1/2 MS+IBA0.8 mg/L+蔗糖30 g/L),14~21 d幼苗长出大量的根系,形成完整的植株。%Tissue culture of maize is relatively difficult,and establishing a stable and efficient transformation system is the premise of maize transgene.Using elite inbred lines(Qi 319,478,502,Huang C and 7922)as explants,the effects of different genotypes,embryo sizes and plant growth regulator concentrations on callus induction and regeneration was studied.The results showed that the frequency of callus induction of 1.5 mm Qi 319 embryos was highest,which reached 86.2%;2,4-D 1.5 mg/L solution was

  1. Gas centrifuge enrichment plants inspection frequency and remote monitoring issues for advanced safeguards implementation

    Energy Technology Data Exchange (ETDEWEB)

    Boyer, Brian David [Los Alamos National Laboratory; Erpenbeck, Heather H [Los Alamos National Laboratory; Miller, Karen A [Los Alamos National Laboratory; Ianakiev, Kiril D [Los Alamos National Laboratory; Reimold, Benjamin A [Los Alamos National Laboratory; Ward, Steven L [Los Alamos National Laboratory; Howell, John [GLASGOW UNIV.

    2010-09-13

    Current safeguards approaches used by the IAEA at gas centrifuge enrichment plants (GCEPs) need enhancement in order to verify declared low enriched uranium (LEU) production, detect undeclared LEU production and detect high enriched uranium (BEU) production with adequate probability using non destructive assay (NDA) techniques. At present inspectors use attended systems, systems needing the presence of an inspector for operation, during inspections to verify the mass and {sup 235}U enrichment of declared cylinders of uranium hexafluoride that are used in the process of enrichment at GCEPs. This paper contains an analysis of how possible improvements in unattended and attended NDA systems including process monitoring and possible on-site destructive analysis (DA) of samples could reduce the uncertainty of the inspector's measurements providing more effective and efficient IAEA GCEPs safeguards. We have also studied a few advanced safeguards systems that could be assembled for unattended operation and the level of performance needed from these systems to provide more effective safeguards. The analysis also considers how short notice random inspections, unannounced inspections (UIs), and the concept of information-driven inspections can affect probability of detection of the diversion of nuclear material when coupled to new GCEPs safeguards regimes augmented with unattended systems. We also explore the effects of system failures and operator tampering on meeting safeguards goals for quantity and timeliness and the measures needed to recover from such failures and anomalies.

  2. Genótipos de milho com alta capacidade para embriogênese somática e regeneração de plantas obtidos a partir de calos Genotypes with high somatic embryogenesis and plant regeneration capacity obtained from tissue culture

    Directory of Open Access Journals (Sweden)

    Janay Almeida dos Santos-Serejo

    2000-12-01

    Full Text Available Como parte de um programa que visa a seleção de linhagens adaptadas a regiões tropicais, com a capacidade para regenerar plantas a partir de calos embriogênicos de curta duração, foram investigadas três linhagens obtidas a partir de uma variedade de milho tipo flint, e seus respectivos híbridos. As culturas foram obtidas a partir de embriões imaturos inoculados em meio N6 suplementado com 1,5 mg L-1 de 2,4-D e prolina 12 mM. A frequência de calos embriogênicos 45 dias após o início da cultura foi semelhante aos melhores genótipos descritos na literatura (83-99%, refletindo a alta qualidade dos genótipos testados para o estabelecimento de culturas de curta duração. O número médio de plantas férteis regeneradas em culturas com 2-3 meses de idade variou de 2 a 8,15 por calo, destacando-se os híbridos 13342/5 x 13342/2 e 132331/1 x 13342/5. Os resultados mostram que estes genótipos são promissores para utilização em programas envolvendo transformação de plantas e propagação de genótipos.As part of a breeding program to select tropical maize lines which are able to regenerate plants from embryogenic calli, three lines obtained from a flint maize variety, and their respective hybrids, have been investigated. Short-term tissue cultures were obtained from immature embryos inoculated on N6 medium suplemented with 1.5 mg L-1 2,4-D and 12 mM L-proline. The frequency of 45 day-old embryogenic calli was similar to those of the best genotypes described in the literature (83-99%, reflecting the high quality of the genotypes evaluated to estabilish short-term tissue cultures. The average number of fertile regenerated plants in 2-3 month-old cultures ranged from 2 to 8.15 per callus, and the hybrids 13342/5 x 13342/2 and 132331/1 x 13342/5 showed the bestg performance. The results show that these genotypes may be used in programs involving plant transformation and genotype propagation.

  3. Regeneration of begonia plantlets by direct organogenesis

    OpenAIRE

    Mendi, Yalçın Y.; Mendi, Yalcin Y.; Curuk, P.; Kocaman, E.; Unek, C.; Eldoğan, S.; Eldogan, S.; Gencel, G.; Çetiner, Selim; Cetiner, Selim

    2009-01-01

    The economic importance of ornamentals worldwide suggests a bright future for ornamental breeding. Rapid progress in plant molecular biology has great potentials to contribute to the breeding of novel ornamental plants utilizing recombinant DNA technology. The plant cell, tissue or organ culture of many ornamental species and their regeneration are essential for providing the material and systems for their genetic manipulation, and this is therefore the first requirement of genetic engineerin...

  4. Stable Short-Term Frequency Support Using Adaptive Gains for a DFIG-Based Wind Power Plant

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jinsik; Jang, Gilsoo; Muljadi, Eduard; Blaabjerg, Frede; Chen, Zhe; Cheol Kang, Yong

    2016-09-01

    For the fixed-gain inertial control of wind power plants (WPPs), a large gain setting provides a large contribution to supporting system frequency control, but it may cause over-deceleration for a wind turbine generator that has a small amount of kinetic energy (KE). Further, if the wind speed decreases during inertial control, even a small gain may cause over-deceleration. This paper proposes a stable inertial control scheme using adaptive gains for a doubly fed induction generator (DFIG)-based WPP. The scheme aims to improve the frequency nadir (FN) while ensuring stable operation of all DFIGs, particularly when the wind speed decreases during inertial control. In this scheme, adaptive gains are set to be proportional to the KE stored in DFIGs, which is spatially and temporally dependent. To improve the FN, upon detecting an event, large gains are set to be proportional to the KE of DFIGs; to ensure stable operation, the gains decrease with the declining KE. The simulation results demonstrate that the scheme improves the FN while ensuring stable operation of all DFIGs in various wind and system conditions. Further, it prevents over-deceleration even when the wind speed decreases during inertial control.

  5. 辣椒枣试管苗叶片再生植株研究%Research of Leaf Regeneration Plant in Ziziphus jujuba Mill.Lajiaozao Test Tube Seedling

    Institute of Scientific and Technical Information of China (English)

    肖蓉; 王国平; 李春燕; 张拥兵

    2012-01-01

    以辣椒枣(Ziziphus jujuba Mill.)组培苗叶片为试材,研究了不同培养方式、接种方式以及不同生长调节剂对离体叶片诱导不定芽再生的影响.结果表明,适当的暗处理有利于辣椒枣叶片愈伤组织的形成,并能促进愈伤组织尽快形成芽点,有利于缩短叶片再生培养时间;叶片反放便于愈伤组织及芽点的观察,褐化率低,最终的不定芽再生数高于叶片正放,是辣椒枣叶片再生培养的最佳放置方式.正交试验结果表明,基本培养基,TDZ,IBA和糖4个因子对辣椒枣叶片再生影响大小排序为:基本培养基>糖>TDZ> IBA;1/2 MS(大)为最优培养基,WPM不适合作为辣椒枣的叶片再生培养基;辣椒枣组培苗叶片再生的最优培养基为1/2 MS(大)+TDZ 0.3 mg/L+ IBA 0.1 mg/L+糖20 g/L,平均每叶片再生不定芽能达到5.4个.%In the paper, the effect of different culture methods, inoculation methods, growth regulator on Lajiaozao Chinese jujube test-tube seedling leaf regeneration plant was studied. The results showed that: appropriate dark treatment was helpful for the leaf callus formation, and could promote callus to bud as soon as possible to shorten the training time of leaf regeneration. Putting leaf face down was facilitate to callus and bud observation, and it had lower browning rate, higher buds regeneration numbers than putting leaf face up. So it's an optimal inoculation method. The orthogonal test results showed: order of effect on Lajiaozao Chinese jujube leaf regeneration performances from big to small was basic culture medium > sugar > TDZ > IBA. 1/2 MS was the optimal medium; WPM was not suitable for Lajiaozao Chinese jujube leaf regeneration. In one word, the optimal medium for Lajiaozao Chinese jujube leaf regeneration was: 1/2 MS + TDZ 0.3 mg/L + IBA 0.1 mg/L + 20 g/L sugar.

  6. Regeneration method for condensate desalting device

    Energy Technology Data Exchange (ETDEWEB)

    Tsurumi, Takeshi; Kashimura, Makoto

    1998-09-02

    Regeneration of a condensate desalting device in a PWR type power plant is conducted by separating a mixed bed into an anion exchange resin layer and a cation exchange resin layer by back washing after stoppage of passage of water. Regeneration of an anion exchange resin layer is conducted by injecting alkali (hydrogen) carbonate such as sodium carbonate and potassium hydrogen carbonate, and extruding them with purified water and then injecting alkali hydroxide, extruding and further washing with purified water. Regeneration of a cation exchange resin layer is conducted by injecting acids such as hydrochloric acid and sulfuric acid followed by extrusion and washing. It is preferable that a liquid formed by mixing the regenerated liquid wastes of the anion exchange resin containing alkali (hydro) carbonate and regenerated liquid wastes of the cationic exchange resin containing acids and allowing generated carbon dioxide to be absorbed to alkali hydroxide is used as alkali (hydrogen) carbonate for the next regeneration. With such procedures, anion exchange resin which adsorbs decomposed products of amines can be regenerated efficiently. (I.N.)

  7. Regeneration of periodontal tissues: guided tissue regeneration.

    Science.gov (United States)

    Villar, Cristina C; Cochran, David L

    2010-01-01

    The concept that only fibroblasts from the periodontal ligament or undifferentiated mesenchymal cells have the potential to re-create the original periodontal attachment has been long recognized. Based on this concept, guided tissue regeneration has been applied with variable success to regenerate periodontal defects. Quantitative analysis of clinical outcomes after guided tissue regeneration suggests that this therapy is a successful and predictable procedure to treat narrow intrabony defects and class II mandibular furcations, but offers limited benefits in the treatment of other types of periodontal defects.

  8. 湖北麦冬花药愈伤组织诱导及再生植株的获得%Callus induction and plant regeneration of Liriope spicata var. prolifera anther

    Institute of Scientific and Technical Information of China (English)

    周群; 周健丘; 王小刚; 王菁菁; 李敬文; 陈家春

    2009-01-01

    Objective: To study the technique of the callus induction from anther and plant regeneration of medicinal plants Liriope spicata var. prolifera. Method: Callus was induced from anther of L. spicata var. prolifera on a MS medium supplemented with different hormones. The squash methods combined with a microscope were used to analyze chromosomes of regenerated plantlets.regenerated plantlets originated from somatic cells. At the same time, the effects of pretreatment of low temperature at 4 ℃ on the callus induction were studied and discussed. Conclusion: This paper sets up the method of tissue culture of anther somatic-cells and intermediate propagation of L. spicata var. prolifera.%目的:探讨药用植物湖北麦冬花药愈伤组织诱导和植株再生条件.方法:以湖北麦冬花药为外植体,采用MS培养基,附加不同的植物激素进行实验.常规压片法结合显微镜进行再生植株染色体的计数分析.结果:MS+2,4-D 1.0 mg·L~(-1)+KT 2.0 mg·L~(-1)诱导愈伤组织效果最好,愈伤组织诱导率可达41.07%.MS+6-BA 1.5~2.0 mg·L~(-1)+NAA0.1~0.3mg·L~(-1)适于不定芽的诱导,不定芽转入附加NAA 0.1~0.3 mg·L~(-1)的1/2 MS的生根培养基上,生根后获得完整的再生植株,再生植株为体细胞起源.同时,讨论了4℃低温预处理对愈伤组织诱导的影响.结论:建立了湖北麦冬花药体细胞组织培养体系和快速繁殖途径.

  9. Establishment of an Efficient Regeneration System Amenable to Agrobacterium Mediated Transformation of Two Elite Indica Rice Varieties of North East India

    Directory of Open Access Journals (Sweden)

    Mohitosh Dey

    2015-12-01

    Full Text Available An efficient plant regeneration system from embryogenic callus of two elite indica rice (Oryza sativa spp. indica varieties of Northeast India, Ketokijoha and Monoharsali is established. The effect of auxin, 2,4-dicholorophenoxy acetic acid (2,4-D on callus induction was optimized. Friable, nodular and creamish-white embryogenic calli were induced from mature seeds on NB medium supplemented with 2.5 mg/l 2,4-D. Plants were regenerated from 40-50 days old embryogenic callus on NB medium containing 0.5 mg/l BAP (6-benzylaminopurine and 0.25 mg/l ABA (abscisic acid. Regenerated plants with multiple tillers were rooted on half strength MS medium and rooted plants were acclimatized with 94% survival rate. Higher frequency of callus induction as well as plant regeneration was recorded in Ketokijoha as compared to Monoharsali. The calli of both the varieties were found amenable to Agrobacterium-mediated transformation as evident from strong GUS (β-glucuronidase expression. The results may find wide application for genetic improvement for valuable traits these elite indica rice varieties of Northeast India.

  10. Composite Matrix Regenerator for Stirling Engines

    Science.gov (United States)

    Knowles, Timothy R.

    1997-01-01

    This project concerns the design, fabrication and testing of carbon regenerators for use in Stirling power convertors. Radial fiber design with nonmetallic components offers a number of potential advantages over conventional steel regenerators: reduced conduction and pressure drop losses, and the capability for higher temperature, higher frequency operation. Diverse composite fabrication methods are explored and lessons learned are summarized. A pulsed single-blow test rig has been developed that has been used for generating thermal effectiveness data for different flow velocities. Carbon regenerators have been fabricated by carbon vapor infiltration of electroflocked preforms. Performance data in a small Stirling engine are obtained. Prototype regenerators designed for the BP-1000 power convertor were fabricated and delivered to NASA-Lewis.

  11. Embriogênese somática e regeneração de plantas a partir de embrião maduro de aveia Somatic embryogenesis and plant regeneration derived from mature embryos of oat

    Directory of Open Access Journals (Sweden)

    Caren Regina Cavichioli Lamb

    2002-02-01

    Full Text Available Calo embriogênico tem sido o tecido-alvo mais utilizado para transformação genética de cereais. O objetivo deste trabalho foi investigar o estabelecimento de calos embriogênicos e a regeneração de plantas in vitro a partir de embriões maduros de genótipos de aveia (Avena sativa L.. Embriões maduros foram retirados das sementes e colocados em meio MS (Murashige & Skoog, contendo 30,0 g L-1 de sacarose e 2,0 mg L-1 de ácido 2,4-diclorofenoxiacético (2,4-D. Após o período de indução de calos, agregados embriogênicos foram isolados e subcultivados a cada 21 dias para meio fresco. Os calos embriogênicos foram então transferidos para meio de indução de parte aérea, e, na seqüência, as partes aéreas foram transferidas para meio de indução de raízes. Houve diferenças entre genótipos quanto à capacidade de embriogênese somática e regeneração de plantas in vitro a partir de embrião maduro. Este explante permitiu a indução de calos embriogênicos, que se multiplicaram, e que regeneraram in vitro um grande número de plantas de genótipos como UFRGS 7 e UFRGS 19, o que o faz passível de ser utilizado na transformação genética da aveia.Embryogenic callus has been the most used target tissue for cereal genetic transformation. Therefore, the objective of this study was to investigate the establishment of embryogenic calli and the in vitro plant regeneration from mature embryos of oat genotypes (Avena sativa L.. Mature embryos were taken out of the seeds and placed on a culture medium MS (Murashige & Skoog, containing 30,0 mg L-1 of sucrose and 2,0 mg L-1 of 2,4-dichlorophenoxyacetic acid (2,4-D. From the induction period, embryogenic aggregates were isolated and subcultivated each 21 days into a fresh medium. After this period, embryogenic calli were transferred to a medium for shoot regeneration. Subsequently, the shoot was transferred to a medium for root induction. There was variability among genotypes for somatic

  12. Notch Signaling Inhibits Axon Regeneration

    OpenAIRE

    Bejjani, Rachid El; Hammarlund, Marc

    2012-01-01

    Many neurons have limited capacity to regenerate their axons after injury. Neurons in the mammalian CNS do not regenerate, and even neurons in the PNS often fail to regenerate to their former targets. This failure is likely due in part to pathways that actively restrict regeneration; however, only a few factors that limit regeneration are known. Here, using single-neuron analysis of regeneration in vivo, we show that Notch/lin-12 signaling inhibits the regeneration of mature C. elegans neuron...

  13. IN VITRO REGENERATION CASTOR (RICINUS COMMUNIS L.) USING COTYLEDON EXPLANTS

    Science.gov (United States)

    A novel plant regeneration protocol was established for castor (Ricinus communis L.), an important oilseed crop. Mature seed-derived cotyledon explants produced adventitious shoots when placed on Murashige and Skoog (MS) medium containing thidiazuron (TDZ). The rate of shoot regeneration was maximal...

  14. High efficiency regeneration and genetic stability analysis of somatic ...

    African Journals Online (AJOL)

    Administrator

    2011-09-07

    Sep 7, 2011 ... polymorphic DNA (RAPD), inter-simple sequence repeat (ISSR) molecular markers and flow cytometry. ... random amplified polymorphic DNA (RAPD), regeneration. .... Detailed information on the primers used in the RAPD and ISSR analysis of ..... monomorphic bands comparing all the regenerated plants.

  15. 藏红花愈伤组织的诱导及植株再生%Callus Induction and Plant Regeneration of Saffron

    Institute of Scientific and Technical Information of China (English)

    王寿芹; 赵永钦; 刘莉莎; 郭仰东

    2011-01-01

    以藏红花(Crocus sativus L.)当年新生小球茎为材料,在MS+0.5 mg/L BA+1.0 mg/L NAA+7%CM(椰乳)培养基上进行初代培养,再转入MS+5 mg/L BA+5 mg/L NAA中进行愈伤组织的诱导,黑暗条件下继代1-2次,51 d就可以获得高诱导串的愈伤组织,愈伤诱导率可达65%.将愈伤组织转入分化培养基MS+5 mg/L BA+5 mg/L NAA中分化丛生芽,丛生芽诱导率高达95%,将丛生芽分成单个植株,最终形成完整再生植株.%The corms of saffron were used as explanta to establiah a regeneration protocol for Cro cus sativus L. The corms incubated in MS + 0. 5 mg/L BA +1.0 mg/L NAA +7 % CM at first, then tranaferred to MS +5 mg/ L BA +5 mg/ L NAA for callus induction. Callus formation was obaened after 51 days , culture and the callus induction rate was 65 % . After four weeks callus induction, the shoot regeneration rate (95 % ) was obtained when 2 mg/L BA was combined with 1 mg/L NAA. The shoot buds were fragmented and transfered to root induction medium containing 0.5 mg/L IBA. Plantlets were then successfully transplanted to greenhouse.

  16. Tobacco mosaic virus infection results in an increase in recombination frequency and resistance to viral, bacterial, and fungal pathogens in the progeny of infected tobacco plants.

    Science.gov (United States)

    Kathiria, Palak; Sidler, Corinne; Golubov, Andrey; Kalischuk, Melanie; Kawchuk, Lawrence M; Kovalchuk, Igor

    2010-08-01

    Our previous experiments showed that infection of tobacco (Nicotiana tabacum) plants with Tobacco mosaic virus (TMV) leads to an increase in homologous recombination frequency (HRF). The progeny of infected plants also had an increased rate of rearrangements in resistance gene-like loci. Here, we report that tobacco plants infected with TMV exhibited an increase in HRF in two consecutive generations. Analysis of global genome methylation showed the hypermethylated genome in both generations of plants, whereas analysis of methylation via 5-methyl cytosine antibodies demonstrated both hypomethylation and hypermethylation. Analysis of the response of the progeny of infected plants to TMV, Pseudomonas syringae, or Phytophthora nicotianae revealed a significant delay in symptom development. Infection of these plants with TMV or P. syringae showed higher levels of induction of PATHOGENESIS-RELATED GENE1 gene expression and higher levels of callose deposition. Our experiments suggest that viral infection triggers specific changes in progeny that promote higher levels of HRF at the transgene and higher resistance to stress as compared with the progeny of unstressed plants. However, data reported in these studies do not establish evidence of a link between recombination frequency and stress resistance.

  17. Community structure and population regeneration of an endangered plant, Thuja sutchuenensis%濒危植物崖柏群落特征及种群更新研究

    Institute of Scientific and Technical Information of China (English)

    王鑫; 张华雨; 李宗峰; 张世强; 王国行; 邓洪平

    2016-01-01

    Evaluating community structure where those endangered plant species occur and their population regeneration are essential for planning protection strategies. Thuja sutchuenensis, a critically endangered species restricted to a single population on the southern side of the Dabashan Mountain, Chongqing, southwestern China, has received little attention so far. We conducted a field investigation into Th. sutchuenensis community on community structure, floristic composition, stratification structure, size structure population and the regeneration of Th. sutchuenensis to provide an effective reference and scientific basis for the protection and management of the remaining Th. sutchuenensis. 10 stands ( size:20 mí20 m) were selected for sampling after repeated reconnaissance based on the factors of altitude, site conditions and so forth. The results showed that the population of Th. sutchuenensis was isolated into several smaller populations because of the habitat fragmentation, and “island” pattern. The community had high level of biodiversity and species richness (182 species belonging to 156 genera and 75 families were found, most of which belonged to Rosaceae, Liliaceae, Compositae, Lauraceae, and Cornaceae families);Gleason, Simpson, Shannon-Wiener diversity and Pielou index were high in the tree layer and shrub layer. The Th. sutchuenensis was mainly distributed in the vertical structure of shrub, lower and middle layers except upper tree layer. There were serious obstacles to population regeneration of Th. sutchuenensis because of the discontinuous distribution of the diameter of individuals. Meanwhile, the remaining Th. sutchuenensis population development was in an unstable environment, and the succession of broadleaf trees led negative influences on the regeneration of Th. sutchuenensis. We conclude that obstacle to the population regeneration of Th. sutchuenensis might be caused by the invasion and development of broadleaf trees in the community. We

  18. Artificial regeneration of major oak (Quercus) species in the eastern United States - a review of the literature

    Science.gov (United States)

    Daniel C. Dey; Douglass Jacobs; Ken McNabb; Gary W. Miller; V. Baldwin; G. Foster

    2008-01-01

    Although natural regeneration is often the best method for establishing new oak (Quercus spp.) stands, there are increasingly more situations in which high potential for oak regeneration failure dictates the use of artificial regeneration including direct seeding and planting seedlings. Additionally, afforestation planting programs frequently...

  19. Plant compensatory growth in aspen seedlings: the role of frequency and intensity of herbivory and resource availability

    Science.gov (United States)

    Nadir Erbilgin; David A. Galvez; Bin Zhang

    2012-01-01

    Plant ecologists have debated the mechanisms used by plants to cope with the impact of herbivore damage for more than a century. During that time, plant resistance mechanisms, which reduce the amount of herbivore damage before and during herbivory, have received most of the attention, while plant tolerance mechanisms, which may minimize the impacts of damage after...

  20. Stirling convertor regenerators

    CERN Document Server

    Ibrahim, Mounir B

    2011-01-01

    Stirling Convertor Regenerators addresses the latest developments and future possibilities in the science and practical application of Stirling engine regenerators and technology. Written by experts in the vanguard of alternative energy, this invaluable resource presents integral scientific details and design concepts associated with Stirling converter regenerators. Content is reinforced with novel insights and remarkable firsthand experience that the authors and their colleagues acquired while working at the National Aeronautics and Space Administration (NASA) and other leading organizations.

  1. Organogênese direta de explantes cotiledonares e regeneração de plantas de mogango Direct organogenesis of cotyledon explants and plant regeneration of squash

    Directory of Open Access Journals (Sweden)

    André Luís Lopes da Silva

    2006-06-01

    Full Text Available Os objetivos foram induzir a organogênese direta de explantes cotiledonares de mogango e estudar a regeneração de plântulas completas a partir das brotações adventícias. Foram utilizados cotilédones como explantes, originados das plântulas de mogango com 20 dias após a semeadura. O meio basal utilizado foi o MS (MURASHIGE & SKOOG, 1962 suplementado com 30g L-1 de sacarose e 7g L-1 de agar. Foram testadas as concentrações de 6-benzilaminopurina (BAP de 0; 0,5; 1,0 e 2,0mg L-1. Explantes de ápices caulinares e segmentos nodais de brotações adventícias foram então cultivados em meio MS suplementado com 30g L-1 de sacarose e 7g L-1 de agar. Maiores concentrações de BAP no meio MS promoveram um aumento da percentagem de explantes cotiledonares com brotações adventícias e uma redução da percentagem de enraizamento. Explantes de segmentos nodais e ápices caulinares oriundos de brotações adventícias cresceram e enraizaram em meio MS sem reguladores de crescimento. Altas percentagens de enraizamento dependem do tamanho dos explantes utilizados.The objectives were to induce direct organogenesis of squash cotyledons and to study the regeneration of complete plantlets from adventitious shoot. Cotyledon explants of 20-day seedlings were cultured in MS (MURASHIGE & SKOOG, 1962 medium supplemented with 30g L-1 of sucrose and 7g L-1 of agar. The 6-benzilaminopurina (BAP concentrations of 0, 0.5, 1.0 and 2.0mg L-1 were tested. Apical and nodal explants from adventitious shoots were transferred to MS medium supplemented with 30g L-1 of sucrose and 7g L-1 of agar. Increasing BAP concentrations in the MS medium enhance the percentage of adventitious shoot and reduce the percentage of root organogenesis of squash cotyledon explants. Apical and nodal explants from adventitious shoot regenerated plantlets with roots in MS medium without growth regulators. High percentage of plantlet rooting depends upon the size of the explants.

  2. Germination and In Vitro Regeneration Response of Local Nigerian ...

    African Journals Online (AJOL)

    Prof. Ogunji

    Nigerian Tomato Cultivar using Different Explant Sources. Durosomo, H. A.,1 Popoola, ... development of in vitro regeneration of the crop from various explant sources. The advent of in ..... Geneve, R.L. (1997). Plant propagation: Principles and.

  3. Highly efficient in vitro adventitious shoot regeneration of Adenosma ...

    African Journals Online (AJOL)

    Yomi

    2012-04-10

    Apr 10, 2012 ... Druce is an important aromatic plant, but no information is available regarding its regeneration ... author. E-mail: zjfc_ghxia@126.com; .... percentage of adventitious bud induction and the average number of adventitious buds ...

  4. Adventitious shoot regeneration from cultured leaf explants of Petunia

    African Journals Online (AJOL)

    DIRECTOR

    2012-06-26

    Jun 26, 2012 ... Department of Plant production and Protection, Faculty of Agriculture, An-Najah National University. Nablus ... 1993), nitrogen and calcium effect on regeneration (Frett and Dirr ..... dehydrogenase, and peroxidase activities.

  5. A comparative study of regenerated bamboo, cotton and viscose ...

    African Journals Online (AJOL)

    AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search · USING AJOL ... from natural bamboo fibres in a regeneration process by which bamboo pulp is ... plant in a process similar to that used to manufacture viscose rayon fibres.

  6. Shoot and plantlet regeneration from meristems of Dioscorea ...

    African Journals Online (AJOL)

    SERVER

    2008-04-17

    Apr 17, 2008 ... In vitro culture media capable of regenerating moderate to high shoots and/or plantlets from meristems of two yam ..... Pvt. Ltd, Naraina, New Delhi, India, pp. ... development in medicinal yam in relation to planting material and.

  7. Enhanced regeneration in explants of tomato (Lycopersicon ...

    African Journals Online (AJOL)

    USER

    2010-06-14

    Jun 14, 2010 ... improvement of stress tolerance of crops are primary targets for plant molecular and genetic breeding (Yuasa et al., 2007) ... Abbreviations: CW, Coconut water; IAA, indole acetic acid; .... Rooting of shoots and transfer of plantlets to soil ..... vitro regeneration system in Sorghum [Sorghum bicolor (L.) Moench].

  8. A procedure for tuning automatic controllers with determining a second-order plant model with time delay from two points of a complex frequency response

    Science.gov (United States)

    Kuzishchin, V. F.; Petrov, S. V.

    2012-10-01

    The problem of obtaining the mathematical model of a plant in the course of adaptively tuning the operating automatic closed-loop control systems is considered. A new method is proposed for calculating the parameters of a model with four free coefficients represented by two inertial sections with a time delay. The model parameters are calculated from the data of experiments on determining two points of a plant's complex frequency response. The results from checking the performance of the method in combination with obtaining information on the plant dynamics by applying the Fourier transform to the impulse transient response of the system are presented. The PID controller is tuned using a parameter scanning algorithm with directly checking the amplitude-frequency response of the closed-loop system, using which the stability margin can be calculated and different quality criteria can be applied.

  9. 40 CFR 1033.535 - Adjusting emission levels to account for infrequently regenerating aftertreatment devices.

    Science.gov (United States)

    2010-07-01

    ... equation: EFA = (F)(EFH) + (1-F)(EFL) Where: F = the frequency of the regeneration event during normal in... from a test segment in which the regeneration occurs. EFL = measured emissions from a test segment in... factor (UAF) using the following equation: UAF = EFA−EFL (2) If regeneration occurs or starts to...

  10. Effects of NAA and BAP, double-layered media, and light distance on in vitro regeneration of Nelumbo nucifera Gaertn. (lotus), an aquatic edible plant.

    Science.gov (United States)

    Mahmad, Noraini; Taha, Rosna Mat; Othman, Rashidi; Saleh, Azani; Hasbullah, Nor Azlina; Elias, Hashimah

    2014-01-01

    In vitro direct regeneration of Nelumbo nucifera Gaertn. was successfully achieved from immature explants (yellow plumule) cultured on a solid MS media supplemented with combinations of 0.5 mg/L BAP and 1.5 mg/L NAA which resulted in 16.00 ± 0.30 number of shoots per explant and exhibited a new characteristic of layered multiple shoots, while normal roots formed on the solid MS basal media. The double-layered media gave the highest number of shoots per explant with a ratio of 2 : 1 (liquid to solid) with a mean number of 16.67 ± 0.23 shoots per explant with the formation of primary and secondary roots from immature explants. In the study involving light distance, the tallest shoot (16.67 ± 0.23 mm) obtained from the immature explants was at a light distance of 200 mm from the source of inflorescent light (1000 lux). The plantlets were successfully acclimatized in clay loam soil after 8 months being maintained under in vitro conditions.

  11. An energy storage and regeneration system

    DEFF Research Database (Denmark)

    2006-01-01

    caverns. When the energy demand exceeds the power production capacity of the plant, the stored gases are burned and the thermal energy is converted into electricity in gas turbine generators. The regenerated electrical power is then used to supplement the output of the electric power plant to meet......  The present invention relates to a method and a system for storing excess energy produced by an electric power plant during periods of lower energy demand than the power plant production capacity. The excess energy is stored by hydrolysis of water and storage of hydrogen and oxygen in underground...... the higher level of energy demand....

  12. PLETHORA Genes Control Regeneration by a Two-Step Mechanism.

    Science.gov (United States)

    Kareem, Abdul; Durgaprasad, Kavya; Sugimoto, Kaoru; Du, Yujuan; Pulianmackal, Ajai J; Trivedi, Zankhana B; Abhayadev, Pazhoor V; Pinon, Violaine; Meyerowitz, Elliot M; Scheres, Ben; Prasad, Kalika

    2015-04-20

    Regeneration, a remarkable example of developmental plasticity displayed by both plants and animals, involves successive developmental events driven in response to environmental cues. Despite decades of study on the ability of the plant tissues to regenerate a complete fertile shoot system after inductive cues, the mechanisms by which cells acquire pluripotency and subsequently regenerate complete organs remain unknown. Here, we show that three PLETHORA (PLT) genes, PLT3, PLT5, and PLT7, regulate de novo shoot regeneration in Arabidopsis by controlling two distinct developmental events. Cumulative loss of function of these three genes causes the intermediate cell mass, callus, to be incompetent to form shoot progenitors, whereas induction of PLT5 or PLT7 can render shoot regeneration hormone-independent. We further show that PLT3, PLT5, and PLT7 establish pluripotency by activating root stem cell regulators PLT1 and PLT2, as reconstitution of either PLT1 or PLT2 in the plt3; plt5-2; plt7 mutant re-established the competence to regenerate shoot progenitor cells but did not lead to the completion of shoot regeneration. PLT3, PLT5, and PLT7 additionally regulate and require the shoot-promoting factor CUP-SHAPED COTYLEDON2 (CUC2) to complete the shoot-formation program. Our findings uncouple the acquisition of competence to regenerate shoot progenitor cells from completion of shoot formation, indicating a two-step mechanism of de novo shoot regeneration that operates in all tested plant tissues irrespective of their origin. Our studies reveal intermediate developmental phases of regeneration and provide a deeper understanding into the mechanistic basis of regeneration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Reproductive phenology, seed removal and early regeneration in relation to distance from parental plants of a native palm in small Atlantic forest fragments

    Directory of Open Access Journals (Sweden)

    Vanessa Mariano

    2016-01-01

    Full Text Available ABSTRACT The Brazilian Atlantic Forest is a global biodiversity hotspot, but most of what remains are small fragments. Small fragments are often harsh environments for forest plant recruitment due to edge effects and the loss of frugivorous animals that provide seed dispersal. We recorded the one-year reproductive phenology of the keystone palm Syagrus romanzoffiana in small (<2.5ha Atlantic Forest fragments in southeastern Brazil. We tested the Janzen-Connell hypothesis with seed-removal experiments and followed the five-year survival of recruits in relation to the distance from parental plants. Palms produced many fruits throughout the year (mean 2,600/plant. More seedlings were found away from parental plants than near them, thereby supporting the Janzen-Connell hypothesis. Almost 45% of seedlings alive in 2010 were dead five years later, but recruitment of new seedlings compensated for this mortality. Distance-dependent factors influenced the density of early ontogenetic stages, but had limited effects on juveniles or on seed removal. High seed production, seed dispersal provided by disturbance-tolerant frugivores and the relatively long-term survival of adults, seedlings and juveniles seem to allow the persistence of S. romanzoffiana in the forest fragments, but possibly at the cost of an increased clumped distribution and reduced gene flow at the landscape scale.

  14. Genetic selection and liquid medium conditions improve the yield of androgenetic plants from diploid potatoes.

    Science.gov (United States)

    Uhrig, H

    1985-12-01

    Solatium tuberosum L. diploid strains with superior androgenetic capacity have been selected for from androgenetic progenies of unselected diploid material. The paper also demonstrates that the use of a liquid medium for culturing potato anthers, instead of the conventional solid agar plates, improves the yield of androgenetic embryoids. The new method, associated with two successive cycles of selection for superior androgenetic response, allows the induction and regeneration of microspore derived plants on a large scale. The best genotype (clone 21 in this paper) regenerates androgenetic plants with a frequency around 30 per each anther plated. Over 80% of the regenerated plants are diploid. It is suggested that the androgenetic embryoids mainly originate from unreduced microspores by a mechanism which maintains a heterozygous or a partly heterozygous genetic situation.

  15. Effect of air desiccation and salt stress factors on in vitro regeneration of rice (Oryza sativa L.)

    Science.gov (United States)

    Siddique, Abu Baker; Ara, Israt; Islam, S M Shahinul; Tuteja, Narendra

    2014-01-01

    Enhancement of callus induction and its regeneration efficiency through in vitro techniques has been optimized for 2 abiotic stresses (salt and air desiccation) using 3 rice genotypes viz. BR10, BRRI dhan32 and BRRI dhan47. The highest frequency of callus induction was obtained for BRRI dhan32 (64.44%) in MS medium supplemented with 2, 4-D (2.5 mgL−1) and Kin (1.0 mgL−1). Different concentrations of NaCl (2.9, 5.9, 8.8 and 11.7 gL−1) were used and its effect was recorded on the basis of viability of calli (VC), relative growth rate (RGR), tolerance index (TI) and relative water content (RWC). It was observed that in all cases BRRI dhan47 showed highest performance on tolerance to VC (45.33%), RGR (1.03%), TI (0.20%) and RWC (10.23%) with 11.7 gL−1 NaCl. Plant regeneration capability was recorded after partial air desiccation pretreatment to calli for 15, 30, 45 and 60 h. In this case BRRI dhan32 gave maximum number of regeneration (76.19%) when 4 weeks old calli were desiccated for 45 h. It was observed that air desiccation was 2-3 folds more effective for enhancing green plantlet regeneration compared to controls. Furthermore, desiccated calli also showed the better capability to survive in NaCl induced abiotic stress; and gave 1.9 fold (88.80%) increased regeneration in 11.7 gL−1 salt level for BRRI dhan47. Analysis of variance (ANOVA) showed that the genotypes, air desiccation and NaCl had significant effect on plant regeneration at P < 0.01. PMID:25482754

  16. 博落回花药离体培养及植株再生研究%In Vitro Culture of Anther and Plant Regeneration forMacleaya cordata

    Institute of Scientific and Technical Information of China (English)

    宋锡帅; 彭琼; 柳亦松; 李炎林; 曾建国

    2014-01-01

    A tissue culture was conducted to eight samples ofMacleaya cordata from different production areas, and the effective in vitro culture of anther and plant regeneration system forMacleaya cordata were established through studied the resources of anther, the cold-stress time (4℃), the heat-stress time (35℃), and the bud harvest time. The results showed that the anther samples ofMacleaya cordata from six production areas can obtain embryoid and regenerated plant; there was significant difference in embryo rate among different production areas, among which the sample from Gaofang of Hunan province had the highest embryo rate by 11.8%; cold-stress of anther at 4℃ for 24~96 h was beneficial for inducing embryoid, and the anther under cold-stress for 48 h was the most easy one to produce embryoid; the heat-stress treatment (35℃) had not signiifcant effect on improving inducing rate of embryoid; the optimal bud harvest time for anther culture was the full-bloom stage.%对8份不同产地的博落回花药进行了组织培养,通过对花药来源、4℃冷激时间、35℃热激时间、取蕾时期等因素的研究,建立了有效的博落回花药离体培养胚状体发生和植株再生体系。结果表明:有6个产地的博落回花药试材可以获得胚状体和再生植株;不同产地间出胚率差异显著,其中来自湖南高坊的材料出胚率最高,为11.8%;在4℃下冷激24~96 h有利于诱导出胚状体,冷激48 h的花药最容易产生胚状体;35℃热激处理对提高胚状体诱导率的作用不明显;花药培养的最佳取蕾时期为盛花期。

  17. The Analysis of Activated Carbon Regeneration Technologies

    Institute of Scientific and Technical Information of China (English)

    姚芳

    2014-01-01

    A series of methods for activated carbon regeneration were briefly introduced.Such as thermal regeneration,chemical regeneration,biochemical regeneration,and newly supercritical fluid regeneration, electrochemical regeneration,light-catalyzed regeneration,and microwave radiation method,and the developing trend of activated carbon regeneration was predicted.

  18. Improvement of in vitro embryo maturation, plantlet regeneration and transformation efficiency from alfalfa (Medicago sativa L.) somatic embryos using Cuscuta campestris extract.

    Science.gov (United States)

    Amini, Massoume; Deljou, Ali; Nabiabad, Haidar Saify

    2016-07-01

    Developmental deficiency of somatic embryos and regeneration to plantlets, especially in the case of transformation, are major problems of somatic embryo regeneration in alfalfa. One of the ways to overcome these problems is the use of natural plant regulators and nutrients in the culture medium of somatic embryos. For investigating the influence of Cuscuta campestris extract on the efficiency of plant regeneration and transformation, chimeric tissue type plasminogen activator was transferred to explants using Agrobacterium tumefaciens, and transgenic plants were recovered using medium supplemented with different concentration of the extract. Transgenic plants were analyzed by PCR and RT-PCR. Somatic embryos of Medicago sativa L. developed into plantlets at high frequency level (52 %) in the maturation medium supplemented with 50 mg 1(-1)C. campestris extract as compared to the medium without extract (26 %). Transformation efficiency was 29.3 and 15.2 % for medium supplemented with dodder extract and without the extract, respectively. HPLC and GC/MS analysis of the extract indicated high level of ABA and some compounds such as Phytol, which can affect the somatic embryo maturation. The antibacterial assay showed that the extract was effective against some strains of A. tumefaciens. These results have provided a scientific basis for using of C. campestris extract as a good natural source of antimicrobial agents and plant growth regulator as well, that can be used in tissue culture of transgenic plants.

  19. Frequency of hepatitis E virus, rotavirus and porcine enteric calicivirus at various stages of pork carcass processing in two pork processing plants.

    Science.gov (United States)

    Jones, Tineke H; Muehlhauser, Victoria

    2017-10-16

    Hepatitis E virus (HEV), rotavirus (RV), and porcine enteric calicivirus (PEC) infections are common in swine and raises concerns about the potential for zoonotic transmission through undercooked meat products. Enteric viruses can potentially contaminate carcasses during meat processing operations. There is a lack of information on the prevalence and control of enteric viruses in the pork processing chain. This study compared the incidence and levels of contamination of hog carcasses with HEV, RV and PEC at different stages of the dressing process. A total of 1000 swabs were collected from 2 pork processing plants on 10 separate occasions over the span of a year. The samples were obtained from random sites on hog carcasses at 4 dressing stages (plant A: bleeding, dehairing, pasteurization, and evisceration; plant B: bleeding, skinning, evisceration, and washing) and from meat cuts. Numbers of genome copies (gc) of HEV, RV and PEC were determined by RT-qPCR. RV and PEC were detected in 100%, and 18% of samples, respectively, after bleeding for plant A and in 98%, and 36% of samples, respectively, after bleeding for plant B. After evisceration, RV and PEC were detected in 21% and 3% of samples, respectively, for plant A and in 1%, and 0% of samples, respectively for plant B. RV and PEC were detected on 1%, and 5% of pork cuts, respectively, for plant A and on 0%, and 0% of pork cuts, respectively, for plant B. HEV was not detected in any pork carcass or retail pork samples from plants A or B. The frequency of PEC and RV on pork is progressively reduced along the pork processing chain but the viruses were not completely eliminated. The findings suggest that consumers could be at risk when consuming undercooked meat contaminated with pathogenic enteric viruses. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  20. Regeneration of Pelargonium in vitro

    Directory of Open Access Journals (Sweden)

    Agnieszka Wojtania

    2013-12-01

    Full Text Available Pelargonium sp. has been a subject of numerous studies to deterimine the effec tiveness of in vitro techniques to produce a large number of pathogen-free plants. Regeneration of pelargonium plants from the different initial explants as well via organogenesis as via somatic embryogenesis has been obtained. The most effective adventitious shoot formation has been achieved from shoot tips and axillary buds using cytokinin or cytokinin/auxin combinations. Leaf explants, whose general have lower organogenic potency, regenerate better in the presence of thidiazuron. This growth regulator stimulate the somatic embryos production from hypocotyl and cotyledone explants too. The main problem in tissue culture propagation of Pelargonium has been the high tendency to formation of vigorously growing callus with low organogenic potency and rapid senescence of cultures. Moreover, the significant differen ces in requirements to the medium composition (minerals, organic compounds and growth regulators between Pelargonium cultivars has been observed. This makes difficult to develop an universaI method of Pelargonium micropropagation.

  1. Micropropagation of some ornamental plants

    OpenAIRE

    Koleva Gudeva, Liljana; Spasenoski, Mirko

    2002-01-01

    Till now many horticulture plants have been successfully regenerated on in vitro conditions. Among them there are ornamental plants such as: Rosa-miniature pot roses; myrillocatus geometrizans-cacti, succulent plant; Echinopsis spachiana-cacti, succulent plant and Dianthus cariophyllus-carnation. Regeneration or micropropagation has been used for production of copies(clones) of the original unique plants(Hussery, 1986). Depending on the species, apical or axillar buds was used for micropro...

  2. Regeneration and reprogramming compared

    Directory of Open Access Journals (Sweden)

    Robles Vanesa

    2010-01-01

    Full Text Available Abstract Background Dedifferentiation occurs naturally in mature cell types during epimorphic regeneration in fish and some amphibians. Dedifferentiation also occurs in the induction of pluripotent stem cells when a set of transcription factors (Oct4, Sox2, Klf4 and c-Myc is over expressed in mature cell types. Results We hypothesised that there are parallels between dedifferentiation or reprogramming of somatic cells to induced pluripotent stem cells and the natural process of dedifferentiation during epimorphic regeneration. We analysed expression levels of the most commonly used pluripotency associated factors in regenerating and non-regenerating tissue and compared them with levels in a pluripotent reference cell. We found that some of the pluripotency associated factors (oct4/pou5f1, sox2, c-myc, klf4, tert, sall4, zic3, dppa2/4 and fut1, a homologue of ssea1 were expressed before and during regeneration and that at least two of these factors (oct4, sox2 were also required for normal fin regeneration in the zebrafish. However these factors were not upregulated during regeneration as would be expected if blastema cells acquired pluripotency. Conclusions By comparing cells from the regeneration blastema with embryonic pluripotent reference cells we found that induced pluripotent stem and blastema cells do not share pluripotency. However, during blastema formation some of the key reprogramming factors are both expressed and are also required for regeneration to take place. We therefore propose a link between partially reprogrammed induced pluripotent stem cells and the half way state of blastema cells and suggest that a common mechanism might be regulating these two processes.

  3. Changes in homologous recombination frequency in Arabidopsis thaliana plants exposed to stress depend on time of exposure during development and on duration of stress exposure.

    Science.gov (United States)

    Rahavi, Seyed Mohammad Reza; Kovalchuk, Igor

    2013-10-01

    In the past, we showed that exposure to abiotic and biotic stresses changes the homologous recombination frequency (HRF) in somatic tissue and in the progeny. In current work we planned to answer the following question: do stress intensity/duration and time during exposure influence changes in somatic HRF and transgenerational changes in HRF? Here, we tested the effects of exposure to UV-C, cold and heat on HRF at 7, 14, 21 and 28 days post germination (dpg). We found that exposure at 14 and 21 dpg resulted in a higher increase in HRF as compared to exposure at 7 dpg; longer exposure to UV-C resulted in a higher frequency of HR, whereas prolonged exposure to cold or heat, especially at later developmental stages, had almost no effect on somatic HRF. Exposure at 7 dpg had a positive effect on somatic growth of plants; plants exposed to stress at this age had larger leaves. The analysis of HRF in the progeny showed that the progeny of plants exposed to stress at 7 dpg had an increase in somatic HRF and showed larger sizes of recombination spots on leaves. The progeny of plants exposed to UV-C at 7 dpg and the progeny of plants exposed to cold or heat at 28 dpg had larger leaves as compared to control plants. To summarize, our experiments showed that changes in somatic and transgenerational HRF depend on the type of stress plants are exposed to, time of exposure during development and the duration of exposure.

  4. De novo regeneration of Scrophularia yoshimurae Yamazaki (Scrophulariaceae) and quantitative analysis of harpagoside, an iridoid glucoside, formed in aerial and underground parts of in vitro propagated and wild plants by HPLC.

    Science.gov (United States)

    Sagare, A P; Kuo, C L; Chueh, F S; Tsay, H S

    2001-11-01

    A protocol for de novo regeneration and rapid micropropagation of Scrophularia yoshimurae (Scrophulariaceae) has been developed. Multiple shoot development was achieved by culturing the shoot-tip, leaf-base, stem-node and stem-internode explants on Murashige and Skoog (MS) medium supplemented with 4.44 microM N6-benzyladenine (BA) and 1.07 microM alpha-naphthaleneacetic acid (NAA). Stem-node and shoot-tip explants showed the highest response (100%) followed by stem-internode (74.4%) and leaf-base (7.7%) explants. The shoots were multiplied by subculturing on the same medium used for shoot induction. Shoots were rooted on growth regulator-free MS basal medium and the plantlets were transplanted to soil and acclimatized in the growth chamber. The content of harpagoside, a quantitatively predominant iridoid glycoside, in different plant material was determined by high performance liquid chromatography (HPLC). The analysis revealed that the content of harpagoside in the aerial and underground parts of S. yoshimurae was significantly higher than the marketed crude drug (underground parts of Scrophularia ningpoensis).

  5. Plant regeneration of Rhabdadenia Ragonesei (Apocynaceae by in vitro culturing of leaf explants REGENERACIÓN DE PLANTAS DE RHABDADENIA RAGONESEI (APOCYNACEAE POR CULTIVO IN VITRO DE EXPLANTES FOLIARES

    Directory of Open Access Journals (Sweden)

    Eduardo Flachsland

    2010-08-01

    Full Text Available Plants of Rhabdadenia Ragonesei Woodson (Apocynaceae were regenerated in vitro from leaves explants. The procedure employed includes: 1 Surface sterilization of leaves by immersion in 70% ethanol (10 s followed by 1,1%NaOCl (15 min and three wash with sterile distilled water. 2 Callus and buds induction by culture on Murashige and Skoog medium (MS + 3 mg/L benzyladenine (BAP. 3 Subculture of callus and buds on MS + 1 mg/L BAP, and 4 Rooting on MS + 0.5 mg/L naftalenacetic acid Se regeneraron plantas de Rhabdadenia Ragonesei Woodson (Apocynaceae mediante el cultivo in vitro de explantes foliares en condiciones ambientales controladas. El procedimiento consistió en: 1 Desinfección de las hojas por inmersión en etanol al 70% (10 s seguida de Inmersión en NaOCl al 1,1% (15 min y lavado tres veces con agua destilada estéril. 2 Inducción de callos y yemas mediante el cultivo de explantes foliares en el medio de Murashige y Skoog (MS + 3 mg/L de benciladenina (BAP. 3 Subcultivo de callos y yemas en MS + 1 mg/L de BAP y 4 Enraizamiento de los vastagos obtenidos en MS + 0,5 mg/L de ácido naftalenacético

  6. Tissue culture of Cecropia glaziovii Sneth (urticaceae: vegetative micropropagation and plant regeneration from callus Cultura de tecidos de Cecropia glaziovii Sneth (Urticaceae: micropropagação vegetativa e regeneração de plantas via calos

    Directory of Open Access Journals (Sweden)

    Marcos Nopper Alves

    2010-10-01

    Full Text Available Cecropia glaziovii is a tree with used in Brazilian popular medicine. Methods allowing the clonal propagation of this species are of great interest for superior genotype multiplication and perpetuation. For this reason, we examined the effect of different culture media and different types of explants on adventitious shoot regeneration from callus and buds of C. glaziovii. Leaves, petioles and stipules obtained from aseptically grown seedlings or from pre-sterilized plants were used to initiate cultures. Adventitious shoot regeneration was achieved when apical and axillary buds were inoculated on gelled Murashige & Skoog (MS medium supplemented with 6-benzylaminopurine alone (BAP (1.0, 5.0 or 10.0 mg L-1 or combined with -naphthalene acetic acid (NAA (1.0 or 2.0 mg L-1, after 40 days of culture. Best callus production was obtained after 30 days of petioles' culture on gelled MS medium with 2,4 dichlorophenoxyacetic acid (2,4-D (5.0 mg L-1 combined with BAP (1.0 mg L-1. Successful shoot regeneration from callus was achieved when MS medium supplemented with zeatin (ZEA (0.1 mg L-1 alone or combined with 2,4-D (1.0 or 5.0 mg L-1 was inoculated with friable callus obtained from petioles. All shoots were rooted by inoculation on MS medium supplemented with indole-3-acetic acid (IAA (1.0 mg L-1. Rooted plants transferred to potting soil were successfully established. All in vitro regenerated plantlets showed to be normal, without morphological variations, being also identical to the source plant. Our study has shown that C. glaziovii can be propagated by tissue culture methods, allowing large scale multiplication of superior plants for pharmacological purposes.Cecropia glaziovii é uma planta lenhosa, popularmente usada no Brasil como medicinal. Métodos que visem a sua propagação clonal podem ser de grande utilidade na preservação de seus genótipos de elite. Foram examinados efeitos de diferentes reguladores de crescimento e explantes na forma

  7. Tooth regeneration: Current status

    Directory of Open Access Journals (Sweden)

    Dadu Shifali

    2009-01-01

    Full Text Available Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is likely to revolutionize dental health and well-being of people by regenerating teeth over the next decade.

  8. Tooth regeneration: current status.

    Science.gov (United States)

    Dadu, Shifali S

    2009-01-01

    Regeneration of a functional tooth has the potential to be a promising therapeutic strategy. Experiments have shown that with the use of principles of bioengineering along with adult stem cells, scaffold material, and signaling molecules, tooth regeneration is possible. Research work is in progress on creating a viable bioroot with all its support. A new culture needs to be created that can possibly provide all the nutrients to the stem cells. With the ongoing research, tissue engineering is likely to revolutionize dental health and well-being of people by regenerating teeth over the next decade.

  9. Regeneration Heat Exchange

    Energy Technology Data Exchange (ETDEWEB)

    J. Lin

    2003-07-30

    The original project goals were to establish the viability of the proposed gas turbine regenerator concept by performing the following tasks: (1) Perform detailed design of a working model of the regenerator concept. (2) Construct a ''bench-top'' model of the regenerator concept based upon the detail design. (3) Test the bench-top model and gather data to support the concept's viability. The project funding was used to acquire the tools and material to perform the aforementioned tasks.

  10. Some perspective decisions for the regeneration system equipment of the thermal and nuclear power plants decreasing the probability of water ingress into the turbine and rotor acceleration by return steam flow

    Science.gov (United States)

    Trifonov, N. N.; Svyatkin, F. A.; Sintsova, T. G.; Ukhanova, M. G.; Yesin, S. B.; Nikolayenkova, E. K.; Yurchenko, A. Yu.; Grigorieva, E. B.

    2016-03-01

    The regeneration system heaters are one of the sources of possible ingress of the water into the turbine. The water penetrates into the turbine either at the heaters overflow or with the return flow of steam generated when the water being in the heater boils up in the dynamic operation modes or at deenergization of the power-generating unit. The return flow of steam and water is dangerous to the turbine blades and can result in the rotor acceleration. The known protective devices used to prevent the overflow of the low-pressure and high-pressure heaters (LPH and HPH), of the horizontal and vertical heaters of heating-system water (HWH and VWH), as well as of the deaerators and low-pressure mixing heaters (LPMH) were considered. The main protective methods of the steam and water return flows supplied by the heaters in dynamic operation modes or at deenergization of the power-generating unit are described. Previous operating experience shows that the available protections do not fully prevent water ingress into the turbine and the rotor acceleration and, therefore, the development of measures to decrease the possibility of ingress of the water into the turbine is an actual problem. The measures allowing eliminating or reducing the water mass in the heaters are expounded; some of them were designed by the specialists of OAO Polzunov Scientific and Development Association on Research and Design of Power Equipment (NPO CKTI) and are efficiently introduced at heat power plants and nuclear power plants. The suggested technical solutions allow reducing the possibility of the water ingress into the turbine and rotor acceleration by return steam flow in the dynamic operation modes or in the case of power generating unit deenergization. Some of these solutions have been tested in experimental-industrial exploitation and can be used in industry.

  11. Asymbiotic seed germination and high-frequency seedling regeneration of Spiranthes sinensis,an endangered orchid%濒危植物盘龙参种子的非共生萌发及种苗的快繁研究

    Institute of Scientific and Technical Information of China (English)

    丁兰; 张丽; 杨宁; 刘国安

    2014-01-01

    Seeds of Spiranthes sinensis were used to find out appropriate media for in vitro germination and seedling regeneration.Results showed that seeds could germinate on medium without plant growth substances,but failed to develop into seedlings;seedlings formed on medium with 1.0 mgL-1 KT,0.1 mgL-1 IAA and 0.1 mgL-1 GA3 ;while seeds could not germinate on media containing lower concentration auxin (1.2 mgL-1 NAA).Seedlings could remain high proliferation rate (2.8 times)on media containing higher concentrations kinin and lower concentration auxin,they were eventually transplanted to greenhouse after cultured on hardening medium for 80 d.The suitable seedling proliferation and hardening media were 1/2MS+12.0 mgL-1 6-BA+0.1 mgL-1 NAA+10.0 mgL-1 ad-enine and 1/2MS+1.0 mgL-1 KT+0.1 mgL-1 IAA+10.0 mgL-1 adenine,respectively.%以盘龙参种子为材料,筛选离体条件下适宜种子非共生萌发、种苗快繁的培养基.结果表明:盘龙参种子在无植物生长物质的培养基中能够萌发,但不能发育成苗;在含有1.0 mgL-1 KT、0.1 mgL-1 IAA 和0.1 mgL-1 GA3的培养基中萌发,并能进一步发育形成种苗;在较高浓度生长素(1.2 mgL-1 NAA)的培养基中不能萌发.种苗在较高浓度细胞分裂素和较低浓度生长素配比的培养基中能够增殖,最高增殖系数可达到2.8,转入壮苗生长培养基中培养80 d 后可以移栽温室.最适增殖培养基为1/2MS+12.0 mgL-16-BA+0.1 mgL-1 NAA+10.0 mgL-1腺嘌呤;最适壮苗生根培养基为1/2MS+1.0 mgL-1 KT+0.1 mgL-1 IAA+10.0 mgL-1腺嘌呤.

  12. 茶树无菌播种建立植株再生体系%Establishment of Plant Regeneration System of Tea Trees by Asepsis Sowing

    Institute of Scientific and Technical Information of China (English)

    黄燕芬; 吴曦; 周国兰; 赵华富

    2013-01-01

    为提高茶树的繁殖速率,用近成熟的茶树种子以无菌播种方式获得试管苗,再以其茎段为外植体,建立了茶树高效植株再生体系.结果表明,剥除内外种皮的茶树种子发芽率为90%,较保留种皮的完全种子增加了13个百分点;茶树种子胚龄与发芽势、发芽率呈正相关,与萌发时间呈负相关;诱导茶树种子萌发适宜培养基为MS+6-BA 3.0 mg/L+IBA 2.0 mg/L+YE 200 mg/L或改良ER+6-BA 2.5 mg/L+NAA 0.2 mg/L;在改良ER+6-BA 1.5 mg/L+NAA 0.2 mg/L继代增殖培养基中培养,带芽组织切块的适宜增殖周期为39 d,增殖倍数5.4;壮苗、诱导根形成的适宜培养基为1/2改良ER+IBA 0.10 mg/L,发根率达80%.%To improve the reproduction rate of tea trees,using the stem of plantlet as explant,which was obtained by asepsis sowing with the nearly mature tea seeds,the optimum regeneration system of tea trees was established.The experimental results showed that the germination rate of tea seeds whose endotesta and exopleura were stripped out was 90%,increased by 13 percentage points compared with the whole seeds.The embryo age of tea seeds had positive correlation with germination energy and germination percentage,but was negatively related to the germination time.To induce tea seed germination,the optimum medium was composed of MS+6-BA 3.0 mg/L+IBA 2.0 mg/L+YE 200 mg/L or ER+6-BA 2.5 mg/L+NAA 0.2 mg/L.The tissue slicing of bud indicated that the suitable proliferation cycle was 39 days with proliferation multiple of 5.4 in the modified subculture medium (ER+6-BA 1.5 mg/L+NAA 0.2 mg/L).In addition,the optimum medium for making seedling strong and inducing root formation was modified 1/2 ER+IBA 0.10 mg/L,leading to 80 % rooting rate.

  13. Community structure and regeneration types of Betula dahurica forest in Badaling forest center of Beijing

    Institute of Scientific and Technical Information of China (English)

    Zhang Yong; Zheng Zhi-hua; Zhang Zhi-xiang

    2007-01-01

    Using plant community analysis methods, we analyzed the floristic characteristics, species composition, community structure, population structure, and spatial distribution patterns of a Betula dahurica forest on the "1238" mountain of Badaling in Beijing, China. The results show that: 1) There are 33 plant species in the B. dahurica community, including 18 woody plant species. The B. dahurica forest is a monodominant community with 75.9% dominance. 2) Based on diameter at breast height (DBH)size class distribution, the population structure of B. dahurica and Acer mono-two heliophyllous and pioneer tree species is cascade-type, with both in an increasing stage. The population structure of Tilia mandshurica and T. mongolica, two shade-tolerant tree species, is inverse-J type, and they have more young seedling individuals and regenerate more stably. They are associated species of the pioneer tree species. The population structure of Quercus mongolica, as the associated species of climax species in the community, is sporadic, and its regeneration is fluctuating and random. Fraxinus rhynchophylla is a shade-tolerant tree species which has a unibar population structure and climax characteristics of pioneer tree species. The relative frequency of young seedlings reached 0.4.3) The dominant species B. dahurica is still in an increasing stage, and the regeneration of other species is steady or partly influences the community, putting the community in the pioneer species stage. From the population structure and distribution frequency ofF. rhynchophylla, the B. dahurica forest will approach to a climax state in the future.

  14. Resin regeneration device for condensate desalter

    Energy Technology Data Exchange (ETDEWEB)

    Segawa, Yoshihiro [Toshiba Engineering Co. Ltd., Kawasaki, Kanagawa (Japan); Hirose, Yuki

    1998-07-28

    The present invention provides a resin regeneration device for a condensate desalter of a nuclear power plant. Namely, both anionic and cationic exchange resins are supplied in a mixed state from a forwarding water desalting tower to an anionic resin regeneration tower. In the anionic resin generation tower, the resin is once separated to an anionic exchange region layer, a mixed resin layer and an cationic exchange resin layer in this order from the upper portion by water injected from a stirring water injection tube disposed at the bottom. Then, water is injected from a developing water injection tube disposed at the lower portion of the mixed resin layer to develop the cationic exchange resin layer and the mixed resin layer to the upper portion of the cationic resin regeneration tower. Subsequently, the amount of the injection of the developing water is reduced to such a flow rate that only the anionic exchange resin is precipitated. Then, a cationic exchange resin layer is formed at the upper portion and an anion exchange resin layer is formed at the lower portion of the developing water injection tube of the cationic resin regeneration tower. The anionic exchange resin is transferred to the anionic exchange resin regeneration tower in this state. According to the present invention, the mixed resin layer can be separated to anionic and cationic exchange resins easily and reliably. (I.S.)

  15. Chemical genetics and regeneration.

    Science.gov (United States)

    Sengupta, Sumitra; Zhang, Liyun; Mumm, Jeff S

    2015-01-01

    Regeneration involves interactions between multiple signaling pathways acting in a spatially and temporally complex manner. As signaling pathways are highly conserved, understanding how regeneration is controlled in animal models exhibiting robust regenerative capacities should aid efforts to stimulate repair in humans. One way to discover molecular regulators of regeneration is to alter gene/protein function and quantify effect(s) on the regenerative process: dedifferentiation/reprograming, stem/progenitor proliferation, migration/remodeling, progenitor cell differentiation and resolution. A powerful approach for applying this strategy to regenerative biology is chemical genetics, the use of small-molecule modulators of specific targets or signaling pathways. Here, we review advances that have been made using chemical genetics for hypothesis-focused and discovery-driven studies aimed at furthering understanding of how regeneration is controlled.

  16. Air regenerating and conditioning

    Science.gov (United States)

    Grishayenkov, B. G.

    1975-01-01

    Various physicochemical methods of regenerating and conditioning air for spacecraft are described with emphasis on conditions which affect efficiency of the system. Life support systems used in closed, hermetically sealed environments are discussed with references to actual application in the Soviet Soyuz and Voskhod manned spacecraft. Temperature and humidity control, removal of carbon dioxide, oxygen regeneration, and removal of bacteria and viruses are among the factors considered.

  17. Nanostructured Biomaterials for Regeneration**

    OpenAIRE

    Wei, Guobao; Ma, Peter X.

    2008-01-01

    Biomaterials play a pivotal role in regenerative medicine, which aims to regenerate and replace lost/dysfunctional tissues or organs. Biomaterials (scaffolds) serve as temporary 3D substrates to guide neo tissue formation and organization. It is often beneficial for a scaffolding material to mimic the characteristics of extracellular matrix (ECM) at the nanometer scale and to induce certain natural developmental or/and wound healing processes for tissue regeneration applications. This article...

  18. Shoot regeneration from petioles and leaves of Vitis X labruscana 'Catawba'.

    Science.gov (United States)

    Cheng, Z M; Reisch, B I

    1989-10-01

    Shoot regeneration and normal plants were obtained from leaf and petiole explants derived from in vitro grown shoots of Vitis X labruscana 'Catawba'. Regeneration was induced in the presence of both 6-benzylaminopurine and indole-3-butyric acid; combinations of 2,4-dichlorophenoxyacetic acid or 2-naphthoxyacetic acid with 6-benzylaminopurine did not permit regeneration from leaf explants. Up to 15% of leaf and 70% of petiole explants regenerated shoots on media with 5.0-10.0 μM BA and 0.1-0.5 μM IBA. Incubation in the dark was required to obtain regeneration. About 50% of shoots developed normally following transfer to light. An average of one shoot regenerated from leaf explants and 3.3 shoots regenerated per petiole explant. Regeneration from petioles and leaves was always from the basipetal end. The interaction of 6-benzylaminopurine with indole-3-butyric acid was also examined.

  19. Silicon Promotes Adventitious Shoot Regeneration and Enhances Salinity Tolerance of Ajuga multiflora Bunge by Altering Activity of Antioxidant Enzyme

    Directory of Open Access Journals (Sweden)

    Iyyakkannu Sivanesan

    2014-01-01

    Full Text Available We investigated the effect of Si concentration on shoot regeneration and salinity tolerance of Ajuga multiflora. Addition of Si to the shoot induction medium significantly increased the frequency of shoot induction. The average number of shoots regenerated per explant decreased on the medium containing NaCl alone, while there was less decrease when the shoot induction medium was supplemented with both NaCl and Si. The shoot induction percentage increased linearly with increasing concentration of Si in the NaCl containing medium. Addition of Si to the shoot induction medium significantly increased SOD, POD, APX, and CAT activity in regenerated shoot buds as compared with the control. The inclusion of Si to the NaCl containing medium significantly increased the SOD activity in leaves and roots, while it decreased POD, APX, and CAT activity in both organs. Scanning electron microscopic analysis showed that there are no distinct differences in the structure of stomata between the control and Si-treated plants. However, NaCl treatment significantly affected the structure and number of stomata as compared to the control. Wavelength dispersive X-ray analysis confirmed the high Si deposition in trichomes of plants grown in the Si containing medium but not in plants grown in the medium without Si.

  20. Infection of Early and Young Callus Tissues of Indica Rice BPT 5204 Enhances Regeneration and Transformation Efficiency

    Institute of Scientific and Technical Information of China (English)

    P. MANIMARAN; G. RAVI KUMAR; M. RAGHURAMI REDDY; S. JAIN; T. BHASKAR RAO; S. K. MANGRAUTHIA; R. M. SUNDARAM; S. RAVICHANDRAN; S. M. BALACHANDRAN

    2013-01-01

    A rapid and reproducible method to develop transgenic plants with enhanced transformation efficiency using Agrobacterium has been developed for the elite indica rice variety BPT 5204. Different rice calli aged from 3 to 30 d were co-cultivated with pre-incubated Agrobacterium suspension culture (LBA4404: pSB1, pCAMBIA1301) and incubated in dark for 3 d. Based on the transient GUS gene expression analysis, 6-day-old young cal i showed high transformation frequency fol owed by 21-day-old ones. Thus, both 6-and 21-day-old calli were used for assessing the stable transformation efficiency. It was observed that the 6-day-old young transformed calli showed about 2-fold higher regeneration frequency when compared with 21-day-old calli. The transformation efficiency was enhanced for young calli to 5.9%compared with 0.8%of the 21-day-old calli. Molecular and genetic analysis of transgenic plants (T0) revealed the presence of 1-2 copies of T-DNA integration in transformants and it follows Mendalian ratio in T1 transgenic plants. From the present study, it was concluded that the development of transgenic rice plants in less duration with high regeneration and transformation efficiency was achieved in BPT 5204 by using 6-day-old young calli as explants.

  1. The influence of the solid thermal conductivity on active magnetic regenerators

    DEFF Research Database (Denmark)

    Nielsen, Kaspar Kirstein; Engelbrecht, Kurt

    2012-01-01

    for a range of thermal conductivities, operating frequencies, a long and short regenerator, and finally a regenerator with a low and a high number of transfer units (NTU) regenerator. In this way the performance is mapped out and the impact of the thermal conductivity of the solid is probed. Modeling shows......The influence of the thermal conductivity of the regenerator solid on the performance of a flat plate active magnetic regenerator (AMR) is investigated using an established numerical AMR model. The cooling power at different (fixed) temperature spans is used as a measure of the performance...... that under certain operating conditions, the AMR cycle is sensitive to the solid conductivity. It is found that as the operating frequency is increased it is not only sufficient to have a high NTU regenerator but the regenerator performance will also benefit from increased thermal conductivity in the solid...

  2. Influences of antibiotics on plantlet regeneration via organogenesis in loblolly pine (Pinus taeda L.)

    Institute of Scientific and Technical Information of China (English)

    TANG Wei; Latoya Harris; Ronald J. Newton

    2003-01-01

    Three antibiotics ampicillin, carbenicillin, and cefotaxime were evaluated for their effects on induction, growth, and differentiation of organogenic calli, as well as rooting of regenerated shoots of three loblolly pine (Pinus taeda L.) genotypes. Of the antibiotics administered, cefotaxime maximally increased the frequency of callus formation and growth rate of organogenic calli, carbenicillin maximally increased the frequency of shoot regeneration and the average number of adventitious shoots per piece of organogenic callus, ampicillin maximally decreased the rooting frequency of regenerated shoots and mean number of roots per regenerated shoot, in comparison with antibiotic-free media. Compared with the control, ampicillin minimally increased the frequency of callus formation, cefotaxime minimally increased the frequency of shoot regeneration, and carbenicillin minimally decreased the rooting frequency of regenerated shoots in three loblolly pine genotypes tested. All three antibiotics increased the frequencies of callus formation and shoot regeneration, and reduced the rooting frequency of regenerated shoots suggested that the establishment of an efficient Agrobacterium tumefaciens-mediated transformation protocol for stable integration of foreign genes into loblolly pine need to select a suitable antibiotic. This investigation could be useful for optimizing genetic transformation of conifers.

  3. Carbon Dioxide Capture from Flue Gas Using Dry, Regenerable Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Thomas O. Nelson; Brian S. Turk; Paul D. Box Raghubir P. Gupta

    2006-09-30

    This report describes research conducted between July 1, 2006 and September 30, 2006 on the use of dry regenerable sorbents for removal of carbon dioxide (CO{sub 2}) from coal combustion flue gas. Modifications to the integrated absorber/ sorbent regenerator/ sorbent cooler system were made to improve sorbent flow consistency and measurement reliability. Operation of the screw conveyor regenerator to achieve a sorbent temperature of at least 120 C at the regenerator outlet is necessary for satisfactory carbon dioxide capture efficiencies in succeeding absorption cycles. Carbon dioxide capture economics in new power plants can be improved by incorporating increased capacity boilers, efficient flue gas desulfurization systems and provisions for withdrawal of sorbent regeneration steam in the design.

  4. Somatic embryogenesis and in vitro plant regeneration from pejibaye adult plant leaf primordia Embriogênese somática e regeneração de plantas in vitro a partir de primórdios foliares de pupunheiras adultas

    Directory of Open Access Journals (Sweden)

    Marcílio de Almeida

    2006-09-01

    Full Text Available The aim of this work was to evaluate a protocol for plant regeneration by means of somatic embryos obtained from isolated adult pejibaye leaf primordia, and to describe histological origin of embryos and morphogenetic response. Explants were cultivated in modified MS medium. Mesophyll parenchymatous cells originated meristemoids (preembryonic complex formation induced with 7.1 µM BAP in the first two subculture periods. After polarized structures with 12.9 µM NAA and 3.55 µM BAP were formed in the third subculture, somatic embryos developed and regenerated normal plants. The mesophyll parenchymatous cells display high capacity of direct response to the auxin and cytokinin.O objetivo deste trabalho foi avaliar um protocolo de regeneração de plantas por meio de embriões somáticos, obtidos a partir de primórdios foliares de pupunheiras adultas e identificar a origem histológica dos embriões e descrever as etapas morfogenéticas. Os explantes foram cultivados em meio MS modificado. Células parenquimáticas do mesofilo originaram meristemóides com BAP (7,1 µM nos dois primeiros períodos de subcultura. A polarização das estruturas ocorreu com ANA (12,9 µM e BAP (3,55 µM no terceiro período de subcultura. Meristemóides se desenvolveram em embriões somáticos, regenerando plantas normais. As células parenquimáticas do mesofilo apresentam elevada capacidade de resposta direta à auxina e à citocinina.

  5. Elimination of marker genes from transgenic plants using MAT vector systems.

    Science.gov (United States)

    Ebinuma, Hiroyasu; Sugita, Koichi; Endo, Saori; Matsunaga, Etsuko; Yamada, Keiko

    2005-01-01

    We have developed an efficient system (Multi-Auto-Transformation [MAT] vectors) for the removal of marker genes and to increase the regeneration frequency of transgenic crops without using antibiotic selection, reducing their possible environmental impact. The MAT vector system is designed to use the oncogenes (ipt, iaaM/H, rol) of Agrobacterium, which control the endogenous levels of plant hormones and the cell responses to plant growth regulators, to differentiate transgenic cells, and to select marker-free transgenic plants. The oncogenes are combined with the site-specific recombination system (R/RS). At transformation, the oncogenes regenerate transgenic plants and then are removed by the R/RS system to generate marker-free transgenic plants. The choice of a promoter for the oncogenes and the recombinase (R) gene, the state of plant materials and the tissue culture conditions greatly affect efficiency of both the regeneration of transgenic plants and the generation of marker-free plants. We have evaluated these conditions in several plant species to increase their generation efficiency. This chapter describes our transformation protocols using MAT vectors.

  6. A systemic increase in the recombination frequency upon local infection of Arabidopsis thaliana plants with oilseed rape mosaic virus depends on plant age, the initial inoculum concentration and the time for virus replication.

    Science.gov (United States)

    Yao, Youli; Kathiria, Palak; Kovalchuk, Igor

    2013-01-01

    In the past, we showed that local infection of tobacco leaves with either tobacco mosaic virus or oilseed rape mosaic virus (ORMV) resulted in a systemic increase in the homologous recombination frequency (HRF). Later on, we showed that a similar phenomenon occurs in Arabidopsis thaliana plants infected with ORMV. Here, we tested whether the time of removing the infected leaves as well as viral titer have any effect on the degree of changes in HRF in systemic tissues. An increase in HRF in systemic non-infected tissues was more pronounced when the infected leaves were detached from the infected plants at 60-96 h post-infection, rather than at earlier time. Next, we found that exposure to higher concentrations of inoculum was much more efficient in triggering an increase in HRF than exposure to lower concentrations. Finally, we showed that older plants exhibited a higher increase in HRF than younger plants. We found that an increase in genome instability in systemic tissues of locally infected plants depends on plant age, the concentration of initial inoculums and the time of viral replication.

  7. A systemic increase in the recombination frequency upon local infection of Arabidopsis thaliana plants with oilseed rape mosaic virus depends on plant age, the initial inoculum concentration and the time for virus replication

    Directory of Open Access Journals (Sweden)

    Youli eYao

    2013-03-01

    Full Text Available In the past, we showed that local infection of tobacco leaves with either Tobacco mosaic virus (TMV or Oilseed rape mosaic virus (ORMV resulted in a systemic increase in the homologous recombination frequency (HRF. Later on, we showed that a similar phenomenon occurs in Arabidopsis thaliana plants infected with ORMV. Here, we tested whether the time of removing the infected leaves as well as viral titer have any effect on the degree of changes in HRF in systemic tissues. An increase in HRF in systemic non-infected tissues was more pronounced when the infected leaves were detached from the infected plants at 60-96 hours post infection, rather than at earlier time. Next, we found that exposure to higher concentrations of inoculum was much more efficient in triggering an increase in HRF than exposure to lower concentrations. Finally, we showed that older plants exhibited a higher increase in HRF than younger plants. We found that an increase in genome instability in systemic tissues of locally infected plants depends on plant age, the concentration of initial inoculums and the time of viral replication.

  8. Economic analysis of replacement regeneration and coppice regeneration in eucalyptus stands under risk conditions

    Directory of Open Access Journals (Sweden)

    Isabel Carolina de Lima Guedes

    2011-09-01

    Full Text Available Projects are by their very nature subject to conditions of uncertainty that obstruct the decision-making process. Uncertainties involving forestry projects are even greater, as they are combined with time of return on capital invested, being medium to long term. For successful forest planning, it is necessary to quantify uncertainties by converting them into risks. The decision on whether to adopt replacement regeneration or coppice regeneration in a forest stand is influenced by several factors, which include land availability for new forest crops, changes in project end use, oscillations in demand and technological advancement. This study analyzed the economic feasibility of replacement regeneration and coppice regeneration of eucalyptus stands, under deterministic and under risk conditions. Information was gathered about costs and revenues for charcoal production in order to structure the cash flow used in the economic analysis, adopting the Net Present Value method (VPL. Risk assessment was based on simulations running the Monte Carlo method. Results led to the following conclusions: replacement regeneration is economically viable, even if the future stand has the same productivity as the original stand; coppice regeneration is an economically viable option even if productivity is a mere 70% of the original stand (high-tree planted stand, the best risk-return ratio option is restocking the stand (replacement regeneration by one that is 20% more productive; the probabilistic analysis running the Monte Carlo method revealed that invariably there is economic viability for the various replacement and coppice regeneration options being studied, minimizing uncertainties and consequently increasing confidence in decision-making.

  9. Regeneration of the Barley Zygote in In Vitro Cultured Ovules

    DEFF Research Database (Denmark)

    Holme, Inger B; Brinch-Pedersen, Henrik; Lange, Mette;

    2010-01-01

    In vitro cultures of zygotes and small embryos carry a lot of potential for studying plant embryogenesis and are also highly relevant for plant biotechnology. Several years ago we established an in vitro ovule culture technique for barley that allows the regeneration of plants from zygotes (Holm et...... al., 1995, Sex. Plant. Reprod. 8:49-59). This culture system proved to be highly effective and indications for genotype independency was obtained. To further sustain this we recently investigated the ovule culture response in the cultivar Golden Promise and three cultivars known for low tissue...... pollination. Ovules were grown for 3 weeks on a culture medium where after embryos could be isolated and transferred to regeneration medium. An average of 1.2 green plantlets per ovule could be regenerated from 50 % of the isolated ovules. No genotypic differences were found on embryo induction...

  10. Validation of SNP allele frequencies determined by pooled next-generation sequencing in natural populations of a non-model plant species.

    Science.gov (United States)

    Rellstab, Christian; Zoller, Stefan; Tedder, Andrew; Gugerli, Felix; Fischer, Martin C

    2013-01-01

    Sequencing of pooled samples (Pool-Seq) using next-generation sequencing technologies has become increasingly popular, because it represents a rapid and cost-effective method to determine allele frequencies for single nucleotide polymorphisms (SNPs) in population pools. Validation of allele frequencies determined by Pool-Seq has been attempted using an individual genotyping approach, but these studies tend to use samples from existing model organism databases or DNA stores, and do not validate a realistic setup for sampling natural populations. Here we used pyrosequencing to validate allele frequencies determined by Pool-Seq in three natural populations of Arabidopsis halleri (Brassicaceae). The allele frequency estimates of the pooled population samples (consisting of 20 individual plant DNA samples) were determined after mapping Illumina reads to (i) the publicly available, high-quality reference genome of a closely related species (Arabidopsis thaliana) and (ii) our own de novo draft genome assembly of A. halleri. We then pyrosequenced nine selected SNPs using the same individuals from each population, resulting in a total of 540 samples. Our results show a highly significant and accurate relationship between pooled and individually determined allele frequencies, irrespective of the reference genome used. Allele frequencies differed on average by less than 4%. There was no tendency that either the Pool-Seq or the individual-based approach resulted in higher or lower estimates of allele frequencies. Moreover, the rather high coverage in the mapping to the two reference genomes, ranging from 55 to 284x, had no significant effect on the accuracy of the Pool-Seq. A resampling analysis showed that only very low coverage values (below 10-20x) would substantially reduce the precision of the method. We therefore conclude that a pooled re-sequencing approach is well suited for analyses of genetic variation in natural populations.