Regeneration and acclimatization of salt-tolerant arachis hypogaea plants through tissue culture

International Nuclear Information System (INIS)

Ghauri, E.G.

2006-01-01

Excised embryos of Arachis hypogaea were cultured on Murashige and Skoog's medium (MS medium) supplemented with different combinations of growth hormones. The highest frequency of callus proliferation (80%) was recorded on MS medium mixed with 1.0 mg/1 of 2,4-D and 0.5 mg/1 of BAP. These cultures were treated with 0.65 mg/l of trans-4-hydroxy-L-proline (HyP) a:1d various concentrations (0.1-0.5%) of NaCl. In all cases the presence of salt reduced the fresh mass of callus. Shoot regeneration in the cultures took place when transferred to MS medium supplemented with 1.0 mg/1 of kinetin (Kin) and 0.5 mg/1 of 6-benzyl aminopurine (BAP). Percentage of shoot regeneration decreased with the increase of NaCl (0.1- 0.5%) in the shoot regeneration medium. Root formation in these cultures took place when the cultures were nurtured on MS medium free of growth hormones. Regeneration, hardening and acclimatization of the salt tolerant plants was conducted. (author)

Transformation and regeneration of the holoparasitic plant Phelipanche aegyptiaca

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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.

A new approach for in vitro regeneration of tomato plants devoid of exogenous plant growth hormones.

Science.gov (United States)

Plana, Dagmara; Fuentes, Alejandro; Alvarez, Marta; Lara, Regla M; Alvarez, Félix; Pujol, Merardo

2006-10-01

Many available methodologies for in vitro regeneration of commercial tomato varieties promote not only the production of normal shoots but also individual leaves, shoots without apical meristems and vitrified structures. All these abnormal formations influence and diminish the regeneration efficiency. At the basis of this phenomenon lies callus development. We optimized an alternative procedure by which the regeneration occurs without abnormal shoot formation. The portion including the proximal part of hypocotyls and the radicle was cultured on medium consisting of Murashige and Skoog salts, 4 mg/L thiamine, 100 mg/L mio-inositol and 3% sucrose. After two-three weeks, 60% explants showed adventitious shoot formation. No changes in the morphological characteristics of regenerated plants and fruits were observed as compared with parents. Karyotypic analysis of regenerated plants showed no variations in chromosome number. The optimized procedure offers the advantage of tomato plant regeneration avoiding callus formation, which enables normal plant recovery with an efficiency ranging from 1.45 +/- 0.05 to 2.57 +/- 0.06 shoots per explant in Campbell-28, Amalia, Lignon, and Floradel cultivars.

Plant regeneration from petiole segments of some species in tissue culture

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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.

Rapid plant regeneration of chrysanthemum (Chrysanthemum ...

African Journals Online (AJOL)

STORAGESEVER

2009-05-04

May 4, 2009 ... demand for chrysanthemum, it has become one of the first commercial targets for ... frequency of multiple shoot regeneration response was. 95 and 91%, for nodal ..... Dordrecht, The Netherlands, pp. 91-101. Prasad RN ...

Plant regeneration from protoplasts ofVicia narbonensis via somatic embryogenesis and shoot organogenesis.

Science.gov (United States)

Tegeder, M; Kohn, H; Nibbe, M; Schieder, O; Pickardt, T

1996-11-01

Protoplasts ofVicia narbonensis isolated from epicotyls and shoot tips of etiolated seedlings were embedded in 1.4% sodium-alginate at a final density of 2.5×10(5) protoplasts/ml and cultivated in Kao and Michayluk-medium containing 0.5 mg/I of each of 2,4- dichlorophenoxyacetic acid, naphthylacetic acid and 6 -benzylaminopurine. A division frequency of 36% and a plating efficiency of 0.40-0.5% were obtained. Six weeks after embedding, protoplast-derived calluses were transferred onto gelrite-solidified Murashige and Skoog-media containing various growth regulators. Regeneration of plants was achieved via two morphologically distinguishable pathways. A two step protocol (initially on medium with a high auxin concentration followed by a culture phase with lowered auxin amount) was used to regenerate somatic embryos, whereas cultivation on medium containing thidiazuron and naphthylacetic acid resulted in shoot morphogenesis. Mature plants were recovered from both somatic embryos as well as from thidiazuron-induced shoots.

Factors affecting callus and protoplast production and regeneration of plants from garlic tissue cultures

International Nuclear Information System (INIS)

Al-Safadi, B.; Nabulsi, I.

2001-08-01

Five cultivars of garlic, two explants, six callusing media, six regeneration media, two kinds of light and several doses of gamma irradiation were used to determine the best conditions for callus induction and plant regeneration from garlic tissue cultures. Also, some experiments were conducted to study the possibility to isolate protoplast and regenerate plants. The experiment showed that medium MS9 was good for regenerating plant directly from basal plate without going through callus phase. ANOVA exhibited significant differences among used cultivars in their ability to form callus. No significant difference was observed between 16 hr light and complete darkness in callus growth. However, appearance of callus was generally better on darkness. Cultivar varied in their ability to regenerate and interaction between cultivars and media was observed. Cultivar kisswany was the best in regeneration (38%) and medium MS47 was the best among used media (35%). Light type played a significant role in regeneration of plants where red light was much better than white light in inducing regeneration (68% vs 36%). ANOVA revealed significant effect of low doses of gamma irradiation on stimulation regeneration of plant whereas high doses prevented regeneration. Many experiments were conducted to isolate protoplast and regenerate plants. The best method for culturing was the droplet and the best conditions for incubation were complete darkness at 25 Degreed centigrade. This lead to formation of cell wall but no cell division was observed (author)

TDZ-Induced Plant Regeneration in Jatropha curcas: A Promising Biofuel Plant

KAUST Repository

Kumar, Nitish

2018-03-23

In recent years, Jatropha curcas has pronounced attention due to its capacity of production of biodiesel. Uniform large-scale propagation of J. curcas is one of the significant keys that will eventually decide victory. Direct regeneration is one of the methods which help in the production of uniform and homogenous plant, and TDZ plays an important role in the production of plantlets by direct organogenesis in several number of plant species including J. curcas. Measuring the economical importance of J. curcas and the role of TDZ in shoot regeneration, the present book chapter briefly reviews the impact of TDZ on shoot bud induction from various explants of J. curcas.

TDZ-Induced Plant Regeneration in Jatropha curcas: A Promising Biofuel Plant

KAUST Repository

Kumar, Nitish; Bhatt, Vacha D.; Mastan, Shaik G.; Reddy, Muppala P.

2018-01-01

In recent years, Jatropha curcas has pronounced attention due to its capacity of production of biodiesel. Uniform large-scale propagation of J. curcas is one of the significant keys that will eventually decide victory. Direct regeneration is one of the methods which help in the production of uniform and homogenous plant, and TDZ plays an important role in the production of plantlets by direct organogenesis in several number of plant species including J. curcas. Measuring the economical importance of J. curcas and the role of TDZ in shoot regeneration, the present book chapter briefly reviews the impact of TDZ on shoot bud induction from various explants of J. curcas.

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.

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

KAUST Repository

Kumar, Nitish Chandramohana; Vijay Anand, K. G.; Reddy, Muppala P.

2010-01-01

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.

Establishment of an efficient plant regeneration culture protocol and achievement of successful genetic transformation in Jatropha curcas L.

Science.gov (United States)

Liu, Ying; Liu, Guoxuan; Yang, Yali; Niu, Sufang; Yang, Fuguang; Yang, Shaoxia; Tang, Jianian; Chen, Jianping

2017-12-01

An efficient and reproducible protocol is described for shoot-bud regeneration and Agrobacterium tumefaciens-mediated genetic transformation of J. curcas. Treating the explants with high concentrations (5-120 mg/L) of TDZ for short durations (5-80 min) before inoculation culture increased significantly the regeneration frequency and improved the quality of the regenerated buds. The highest shoot-buds induction rate (87.35%) was achieved when petiole explants were treated with 20 mg/L TDZ solution for 20 min and inoculated on hormone-free MS medium for 30 days. Regenerated shoots of 0.5 cm or a little longer were isolated and grafted to seedling stocks of the same species, and then the grafted plantlets were planted on half-strength MS medium containing 0.1 mg/L IBA and 2 mg/L sodium nitroprusside (SNP). This grafting strategy was found to be very effective, to obtain that healthy grafted plantlets ready for acclimatization within 20 days. By the above mentioned protocol and with general Agrobacterium - mediated genetic transformation methods only 65 days were needed to obtain intact transgenic plants.

Emissions During and Real-world Frequency of Heavy-duty Diesel Particulate Filter Regeneration.

Science.gov (United States)

Ruehl, Chris; Smith, Jeremy D; Ma, Yilin; Shields, Jennifer Erin; Burnitzki, Mark; Sobieralski, Wayne; Ianni, Robert; Chernich, Donald J; Chang, M-C Oliver; Collins, John Francis; Yoon, Seungju; Quiros, David; Hu, Shaohua; Dwyer, Harry

2018-05-15

Recent tightening of particulate matter (PM) emission standards for heavy-duty engines has spurred the widespread adoption of diesel particulate filters (DPFs), which need to be regenerated periodically to remove trapped PM. The total impact of DPFs therefore depends not only on their filtering efficiency during normal operation, but also on the emissions during and the frequency of regeneration events. We performed active (parked and driving) and passive regenerations on two heavy-duty diesel vehicles (HDDVs), and report the chemical composition of emissions during these events, as well as the efficiency with which trapped PM is converted to gas-phase products. We also collected activity data from 85 HDDVs to determine how often regeneration occurs during real-world operation. PM emitted during regeneration ranged from 0.2 to 16.3 g, and the average time and distance between real-world active regenerations was 28.0 h and 599 miles. These results indicate that regeneration of real-world DPFs does not substantially offset the reduction of PM by DPFs during normal operation. The broad ranges of regeneration frequency per truck (3-100 h and 23-4078 miles) underscore the challenges in designing engines and associated aftertreatments that reduce emissions for all real-world duty cycles.

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.

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

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Arzu Ucar Turker

2011-01-01

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.

Plants regeneration from African cowpea variety (Vigna unguiculata ...

African Journals Online (AJOL)

STORAGESEVER

2008-08-18

Aug 18, 2008 ... Vigna unguiculata (L.) Walp. plant was efficiently regenerated from cotyledonary node explants. The shoots multiplication rate was ... Africa, insect pests are often responsible for 100% losses of cowpea yields (Singh and .... 26 days after acclimatization first flower buds were observed; thus plants were ...

Ribosomal DNA sequence analysis of different geographically distributed Aloe Vera plants: Comparison with clonally regenerated plants

International Nuclear Information System (INIS)

Yagi, A.; Sato, Y.; Miwa, Y.; Kabbash, A.; Moustafa, S.; Shimomura, K.; El-Bassuony, A.

2006-01-01

A comparison of the sequences in an internally transcribed spacer (ITS) 1 region of rDNA between clonally regenerated A.vera and same species in Japan, USA and Egypt revealed the presence of two types of nucleotide sequences, 252 and 254 bps. Based on the findings in the ITS 1 region, A.vera having 252 and 254 bps clearly showed a stable sequence similarity, suggesting high conversation of the base peak sequence in the ITS 1 region. However, frequent base substitutions in the 252 bps samples leaves that came from callus tissue and micropropagated plants were observed around the regions of nucleotide positions 66, 99 and 199-201. The minor deviation in clonally regenerated A.vera may be due to the stage of regeneration and cell specification in cases of the callus tissue. In the present study, the base peak sequence of the Its 1 region of rDNA was adopted as a molecular marker for differentiating A.vera plants from geographically distributed and clonally regenerated A.vera plants and it was suggested that the base peak substitutions in the ITS 1 region may arise from the different nutritional and environmental factors in cultivation and plant growth stages. (author)

Full Length Research Paper Plant regeneration of Michelia ...

African Journals Online (AJOL)

Michelia champaca L. is a woody ornamental tree species which has high commercial value to be used as a basic material for perfume, cosmetic, and medicine. The development of an efficient plant regeneration system for M. champaca is essential for the production of Champaca planting material and precondition for ...

Establishment of a high-efficiency plant regeneration and ...

African Journals Online (AJOL)

STORAGESEVER

2009-10-05

Oct 5, 2009 ... presented higher CIP, EIP and plant regeneration percentage (PRP) than others; the four materials, including Huangzao4, Huangye4, Jing24 and Ji853 from Tangsipingtou group, were not easy to be differentiated into plants, in spite of high CIP. Maize inbred line 18-599(red) as a representative was.

Effect of sorbitol in callus induction and plant regeneration in wheat

African Journals Online (AJOL)

STORAGESEVER

2009-12-01

Dec 1, 2009 ... Key words: Callus induction, plant regeneration, wheat, 2,4-D, sorbitol. INTRODUCTION ... regeneration is better on hormone-free medium or that .... AB (interaction). 15 ... element and creates osmotic stress as reported by.

Development of efficient plant regeneration and transformation system for impatiens using Agrobacterium tumefaciens and multiple bud cultures as explants.

Science.gov (United States)

Dan, Yinghui; Baxter, Aaron; Zhang, Song; Pantazis, Christopher J; Veilleux, Richard E

2010-08-09

Impatiens (Impatiens walleriana) is a top selling floriculture crop. The potential for genetic transformation of Impatiens to introduce novel flower colors or virus resistance has been limited by its general recalcitrance to tissue culture and transformation manipulations. We have established a regeneration and transformation system for Impatiens that provides new alternatives to genetic improvement of this crop. In a first step towards the development of transgenic INSV-resistant Impatiens, we developed an efficient plant regeneration system using hypocotyl segments containing cotyledonary nodes as explants. With this regeneration system, 80% of explants produced an average of 32.3 elongated shoots per initial explant plated, with up to 167 elongated shoots produced per explant. Rooting efficiency was high, and 100% of shoots produced roots within 12 days under optimal conditions, allowing plant regeneration within approximately 8 weeks. Using this regeneration system, we developed an efficient Agrobacterium-mediated Impatiens transformation method using in vitro multiple bud cultures as explants and a binary plasmid (pHB2892) bearing gfp and nptII genes. Transgenic Impatiens plants, with a frequency up to 58.9%, were obtained within 12 to 16 weeks from inoculation to transfer of transgenic plants to soil. Transgenic plants were confirmed by Southern blot, phenotypic assays and T1 segregation analysis. Transgene expression was observed in leaves, stems, roots, flowers, and fruit. The transgenic plants were fertile and phenotypically normal. We report the development of a simple and efficient Agrobacterium-mediated transformation system for Impatiens. To the best of our knowledge, there have been no reports of Agrobacterium-mediated transformation of Impatiens with experimental evidence of stable integration of T-DNA and of Agrobacterium-mediated transformation method for plants using in vitro maintained multiple bud cultures as explants. This transformation system

Development of Efficient Plant Regeneration and Transformation System for Impatiens Using Agrobacterium tumefaciens and Multiple Bud Cultures as Explants

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Dan Yinghui

2010-08-01

Full Text Available Abstract Background Impatiens (Impatiens walleriana is a top selling floriculture crop. The potential for genetic transformation of Impatiens to introduce novel flower colors or virus resistance has been limited by its general recalcitrance to tissue culture and transformation manipulations. We have established a regeneration and transformation system for Impatiens that provides new alternatives to genetic improvement of this crop. Results In a first step towards the development of transgenic INSV-resistant Impatiens, we developed an efficient plant regeneration system using hypocotyl segments containing cotyledonary nodes as explants. With this regeneration system, 80% of explants produced an average of 32.3 elongated shoots per initial explant plated, with up to 167 elongated shoots produced per explant. Rooting efficiency was high, and 100% of shoots produced roots within 12 days under optimal conditions, allowing plant regeneration within approximately 8 weeks. Using this regeneration system, we developed an efficient Agrobacterium-mediated Impatiens transformation method using in vitro multiple bud cultures as explants and a binary plasmid (pHB2892 bearing gfp and nptII genes. Transgenic Impatiens plants, with a frequency up to 58.9%, were obtained within 12 to 16 weeks from inoculation to transfer of transgenic plants to soil. Transgenic plants were confirmed by Southern blot, phenotypic assays and T1 segregation analysis. Transgene expression was observed in leaves, stems, roots, flowers, and fruit. The transgenic plants were fertile and phenotypically normal. Conclusion We report the development of a simple and efficient Agrobacterium-mediated transformation system for Impatiens. To the best of our knowledge, there have been no reports of Agrobacterium-mediated transformation of Impatiens with experimental evidence of stable integration of T-DNA and of Agrobacterium-mediated transformation method for plants using in vitro maintained

Somatic Embryogenesis and Plant Regeneration in Eggplant ...

African Journals Online (AJOL)

DR SIDHU

2013-02-20

Feb 20, 2013 ... Two as well as three way interactions of three eggplant genotypes, media compositions and explants. (hypocotyl, cotyledon and leaf) showed significant differences for plant regeneration. Among three explants, hypocotyl induced highest percent callusing, but cotyledon showed best results for somatic.

Establishment of plant regeneration system from anther culture of ...

African Journals Online (AJOL)

ajl yemi

2011-11-28

Nov 28, 2011 ... Plant regeneration of Tagetes patula was achieved from anther explants via adventitious shoot differentiation from callus. The effects of genotype, temperature pretreatment, plant growth regulators, light regimes and sucrose concentration were studied. Eight of ten genotypes tested were successfully.

Frequency of mononuclear diploid cardiomyocytes underlies natural variation in heart regeneration.

Science.gov (United States)

Patterson, Michaela; Barske, Lindsey; Van Handel, Ben; Rau, Christoph D; Gan, Peiheng; Sharma, Avneesh; Parikh, Shan; Denholtz, Matt; Huang, Ying; Yamaguchi, Yukiko; Shen, Hua; Allayee, Hooman; Crump, J Gage; Force, Thomas I; Lien, Ching-Ling; Makita, Takako; Lusis, Aldons J; Kumar, S Ram; Sucov, Henry M

2017-09-01

Adult mammalian cardiomyocyte regeneration after injury is thought to be minimal. Mononuclear diploid cardiomyocytes (MNDCMs), a relatively small subpopulation in the adult heart, may account for the observed degree of regeneration, but this has not been tested. We surveyed 120 inbred mouse strains and found that the frequency of adult mononuclear cardiomyocytes was surprisingly variable (>7-fold). Cardiomyocyte proliferation and heart functional recovery after coronary artery ligation both correlated with pre-injury MNDCM content. Using genome-wide association, we identified Tnni3k as one gene that influences variation in this composition and demonstrated that Tnni3k knockout resulted in elevated MNDCM content and increased cardiomyocyte proliferation after injury. Reciprocally, overexpression of Tnni3k in zebrafish promoted cardiomyocyte polyploidization and compromised heart regeneration. Our results corroborate the relevance of MNDCMs in heart regeneration. Moreover, they imply that intrinsic heart regeneration is not limited nor uniform in all individuals, but rather is a variable trait influenced by multiple genes.

Induction of shoot regeneration in cotyledon explants of the oilseed crop Sesamum indicum L.

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Masochon Zimik

2017-12-01

Full Text Available Sesamum indicum is an ancient oilseed crop known for its high quality edible oil and its medicinally important lignans. The crop is said to be recalcitrant to plant tissue culture thus limiting the use of modern biotechnology for its genetic improvement. We present here a protocol describing plant regeneration through adventitious shoot formation from cotyledons dissected from sesame seeds soaked for four hours in water. Subculturing of the cotyledons after two weeks of culture on to a fresh Murashige and Skoog medium leads to differentiation of adventitious shoots from the proximal cut end of the explant. Culture of cotyledons on a medium containing 9% sucrose for a couple of weeks prior to transfer to MS medium supplemented with 3% sucrose induced a higher frequency of shoot regeneration. The highest frequency of 25% adventitious shoot regeneration was observed for S. indicum variety UMA. This variety also turned out to be the best among the ten genotypes tested for shoot regeneration through tissue culture. While addition of IAA marginally improved regeneration, silver nitrate was found essential for enhancing the frequency of shoot regeneration. The regenerated shoots formed roots on full strength MS medium supplemented with 1 mg/l IBA and the rooted plants were established in soil.

Field evaluation of regenerated plants by somatic embryogenesis from shoots apexes of axillary buds in ´Navolean’ (Musa spp., AAB.

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Jorge López

2005-04-01

Full Text Available The use of shoots apexes from axilary buds for callus induction with embryogenic structures in plantain ‘Navolean’ (Group AAB permitted to develop a plant regeneration method through out somatic embryogenesis. In order to know the phenotypic variants that may be produced with the previously mentioned method , 1000 plants were planted in field conditions in comparison to those coming from somatic embryos obtained from multibuds as initial explants and organogenesis-derived plants (shoot tipsand conventionally derived plants (corms, during two growing cycles. The main morphological characters and yield components were evaluated. The total frequency of somaclonal variation during the first growing cycle in plants coming from somatic embryos obtained from shoots apexes from axilary buds as initial explants were 1.1%, and 8,6% in regenerated plants from somatic embryos obtained from multi-buds as initial explants. Later, in this same growing cycle, plants regenerated from somatic embryos (both sources showed a similar performance between them and they were significantly superior in all evaluated variants in comparison to corm-derived plants. In the second growing cycle, significant differences were not observed in yield components of suckers from evaluated plants, in spite of the propagation method used. With regard to somaclonal variation, the best performance was obtained with shoots apexes from axilary buds as explants. Finally, the feasibility of using the new method was shown. Key words: embryogenic cell suspensions, somaclonal variation

ECONOMIC COMPARATIVE EVALUATION OF COMBINATION OF ACTIVATED CARBON GENERATION AND SPENT ACTIVATED CARBON REGENERATION PLANTS

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TINNABHOP SANTADKHA

2017-12-01

Full Text Available The purpose of this study was to investigate the maximum annual profit of proposed three project plants as follows: (i a generation process of activated carbon (AC prepared from coconut shells; (ii a regeneration process of spent AC obtained from petrochemical industries; and (iii a project combined the AC generation process with the regeneration process. The maximum annual profit obtained from the sole regeneration plant was about 1.2- and 15.4- fold higher than that obtained from the integrated and the generation plants, respectively. The sensitivity of selected variables to net present value (NPV, AC sales price was the most sensitive to NPV while fixed costs of generation and regeneration, and variable cost of regeneration were the least sensitive to NPV. Based on the optimal results of each project plant, the economic indicators namely NPV, return on investment (ROI, internal rate of return (IRR, and simple payback period (SPP were determined. Applying a rule of thumb of 12% IRR and 7-year SPP, the AC sales prices for the generation, regeneration, and integrated plants were 674.31, 514.66 and 536.66 USD/ton of product, respectively. The economic analysis suggested that the sole regeneration project yields more profitable.

THE PARTICULARITIES OF PROLONGED CULTIVATION OF PLANTS-REGENERANTS OF TOMATO INTERSPECIFIC HYBRIDS

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T. N. Miroshnichenko

2015-01-01

Full Text Available The particularities of the changes of the morphological parameters of plants-regenerants of tomato hybrids F1 during prolonged cultivation in conditions of in vitro have been studied. The cultivation during 12 passages in hormoneless MS medium does not lead to somaclonal variants, but act to raise the increasing of coefficient of variability of plants-regenerants features. 

Plants Regeneration Derived From Various on Peanut on Mutant Lines

International Nuclear Information System (INIS)

Dewi, Kumala; Masrizal; Mugiono

1998-01-01

The study of calli, greenspot formation and shoot regeneration on peanut mutant lines has ben conducted by MS media. Three explants derived from shoot tips, embryo and seeding root of two mutant lines a/20/3 and D/25/3/2 were used in this experiment. the explants were cultured on modified MS media enriched by vitamins, growth regulation, amino acids for fourth teen calli were transferred on regeneration media. The ability of calli formation and plant regeneration of each explant and genotypes of plants was varied. Greenspot and shoot formation were observed seventh days after the calli transferred on regeneration media. It is shown that the ability of calli, greenspot and shoot formation of each explants and genotypes was varied. the high ability of calli, greenspot and shoot formation were found in explant derived from shoot tip and embryo. Seedling root explant has lower ability in calli formation, while greenspot and shoot was formatted. The ability of calli, greenspot and shoot formation on A/20/3 mutant line was better than D/25/3/2 mutant line. (author)

Optimization of Callus Induction and Regeneration in Two Fenugreek Landraces as a Medicinal Plant during in vitro Condition

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Hasan Hasani Jifroudi

2017-10-01

productive for direct shoot regeneration than cotyledon explants. Conclusions: Callus induction and direct shoot regeneration are as in vitro tissue culture methods. Plant growth regulators and types of explant and genotype are the most important factors for callus induction and direct shoot regeneration phases. Therefore, optimization of these factors is essential to establish a high frequency of callus induction, direct shoot regeneration and gene transferring to this plant. According to the results of this investigation, it is recommended to apply plant growth regulators that were used in this study for other landraces of fenugreek cultured in Iran and select the best genotypes in response to tissue culture conditions for using in future studies.

Plant regeneration via somatic embryogenesis from root explants of ...

African Journals Online (AJOL)

A system for induction of callus and plant regeneration via somatic embryogenesis from root explants of Hevea brasiliensis Muell. Arg. clone Reyan 87-6-62 was evaluated. The influence of plant growth regulators (PGRs) including 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (6-BA) and kinetin (KT) on ...

Somatic embryogenesis and plant regeneration of Capsicum baccatum L.

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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.

Plant regeneration through indirect organogenesis of chestnut ...

African Journals Online (AJOL)

Mehrcedeh

2013-12-18

Dec 18, 2013 ... Druce-A multiple desert tree. Researcher 1:28-32. Kvaalen H, Gram Daehlen O, Tove Rognstad A, Grǿnstad B,. Egertsdotter U (2005). Somatic embryogenesis for plant production of. Abies lasiocarpa. Can. J. For. Res. 35:1053-1060. Liu CZ, Murch SJ, Demerdash MEL, Saxena PK (2003). Regeneration.

Embryogenesis and plant regeneration from unpollinated ovaries of ...

African Journals Online (AJOL)

Embryogenesis and plant regeneration from unpollinated ovaries of Amorphophallus konjac. Lingling Zhao, Jinping Wu, Ying Diao, Zhongli Hu. Abstract. The system of somatic embryogenesis of Amorphophallus konjac had been built through unpollinated ovaries. The embryogenic calli were induced on Murashige and ...

In vitro embryo rescue and plant regeneration following self ...

African Journals Online (AJOL)

In vitro embryo rescue and plant regeneration following self-pollination with irradiated ... AFRICAN JOURNALS ONLINE (AJOL) · Journals · Advanced Search ... shows that pollen irradiation coupled with self-pollination and embryo rescue ...

The effect of gamma radiation and N-ethyl-N-nitrosourea on cultured maize callus growth and plant regeneration

International Nuclear Information System (INIS)

Moustafa, R.A.K.; Duncan, D.R.; Widholm, J.M.

1989-01-01

Regenerable maize calli of two inbred lines were exposed to 0 to 100 Gy of gamma rays or treated with 0 to 30 mM of N-ethyl-N-nitrosourea (ENU) to determine their effect on growth and plant regeneration capability. Both growth and plant regeneration capacity decreased with increasing levels of either gamma radiation or ENU; however, plant regeneration capacity was more sensitive to either agent than growth. The 50% inhibition dose (I 50 ) for callus growth (fresh-weight gain) was approximately 100 Gy of gamma radiation and 30 mM ENU. The I 50 for plant regeneration capacity of treated callus was approximately 25 Gy of gamma radiation and 2.5 mM ENU. The decrease in plant regeneration capacity correlated with a change in tissue composition of the treated callus from a hard, yellow and opaque tissue to a soft, grayish-yellow and translucent tissue. This change was quantified by measuring the reduction of MnO 4 - to MnO 2 (PR assay) by the callus. These results suggest that the effect of gamma radiation or ENU on plant regeneration capacity must be taken into consideration if these potentially mutagenic agents are to be used on maize callus cultures, for the purpose of producing useful mutations at a whole plant level. The data also suggest that the PR assay may be useful for predicting the actual plant regeneration capacity of maize callus. (author)

In vitro propagation and whole plant regeneration from callus in ...

African Journals Online (AJOL)

user

2011-01-17

Jan 17, 2011 ... Leaf explants and mature embryos of Datura were separately cultured in MS basal medium ... al., 2001). It was found that in vitro culture can enable plants to produce secondary metabolites under controlled culture conditions. Furthermore, the establishment of ..... formation and plant regeneration in tomato.

Callus induction and plant regeneration by Brazilian new elite wheat genotypes

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Eliane Cristina Gruszka Vendruscolo

2008-01-01

Full Text Available The distinction of genotypes responsive to tissue culture and the development of an efficient regenerationsystem are the first steps towards transgenic plant production. Nine Brazilian wheat (Triticum aestivum L. genotypes werecultivated in vitro to evaluate the embryogenetic capacity. The explants (immature zygotic embryos were tested in twodifferent culture media, MS (Murashige and Skoog 1962 and modified MS - MMS (Zhou et al. 1995 with decreasing dosagesof hormone regulators. Three distinct phases were observed in each medium: induction, maintenance and regeneration. Afterinduction, the somatic embryogenesis of calli was evaluated every 21 days. Genotypes responded differently to the differentculture media. The embryogenic response of genotype CD104 was best in both culture media tested. On MMS, the values ofcallus induction, plant regeneration and ratio of regenerated plantlets per rescued embryo of this genotype were 100%, 99.5%and 1.1%, respectively. Genotypes CD104, CD200126 and CDFAPA 2001129 were most responsive on MS (regenerationcapacity of 37.5%, 33.5% and 33% respectively, and therefore interesting for genetic transformation in plant breedingprograms that develop new elite cultivars with a commercial purpose.

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.

Effect of plant growth regulators on regeneration of the endangered ...

African Journals Online (AJOL)

Development of an efficient in vitro regeneration protocol of Calligonum comosum is important and that has achieved to protect the endangered multipurpose medicinally important desert plant in the Kingdom of Bahrain. Nodal segments were used as explants source and the effect of various plant growth regulators (PGRs) ...

Direct and indirect plant regeneration from various explants of ...

African Journals Online (AJOL)

user

2011-04-18

Apr 18, 2011 ... Populus species are important resource for certain branches of industry and have special roles for ... Key words: Poplar, tissue culture, regeneration, organogenesis. .... the best (90 to 100%) adaptation ratio in the plant growth.

Plant regeneration of Michelia champaca L., through somatic ...

African Journals Online (AJOL)

STORAGESEVER

2010-05-03

May 3, 2010 ... as a basic material for perfume, cosmetic, and medicine. The development of an ... Plant regeneration systems of M. champaca through somatic ... The embryogenic cells proliferated and formed somatic embryos (30%) after four to six .... by using MS excel program and Duncan's new multiple range test.

In vitro plant regeneration of Spartina argentinensis Parodi

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Mirian Susana Bueno

2012-07-01

; 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.

Efficient plant regeneration through somatic embryogenesis from callus cultures of Oncidium (Orchidaceae).

Science.gov (United States)

Chen, J -T.; Chang, W -C.

2000-12-07

An efficient method was established for high frequency somatic embryogenesis and plant regeneration from callus cultures of a hybrid of sympodial orchid (Oncidium 'Gower Ramsey'). Compact and yellow-white embryogenic calli formed from root tips and cut ends of stem and leaf segments on 1/2 MS [11] basal medium supplemented with 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ, 0.1-3 mg/l), 2,4-dichlorophenoxyacetic acid (2,4-D, 3-10 mg/l) and peptone (1 g/l) for 4-7 weeks. Embryogenic callus was maintained by subculture on the same medium for callus induction and proliferated 2-4 times (fresh weight) in 1 month. Initiation of somatic embryogenesis and development up to the protocorm-like-bodies (PLBs) from callus cultures was achieved on hormone-free basal medium. Regenerants were recovered from somatic embryos (SEs) after transfer to the same medium and showed normal development. The optimized protocol required about 12-14 weeks from the initiation of callus to the plantlet formation. Generally, the frequency of embryo formation of root-derived callus was higher than stem- and leaf-derived calli. Combinations of naphthaleneacetic acid (NAA) and TDZ significantly promoted embryo formation from callus cultures. The high-frequency (93.8%) somatic embryogenesis and an average of 29.1 SEs per callus (3x3 mm(2)) was found in root-derived callus on a basal medium supplemented with 0.1 mg/l NAA and 3 mg/l TDZ. Almost all the SEs converted and the plantlets grew well with an almost 100% survival rate when potted in sphagnum moss and acclimatized in the greenhouse.

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...... explants of young spikes on the barley medium J 25-8. The capacity for plant regeneration was dependent on the wild parental species. In particular, combinations with four related wild species, viz. H. jubatum, H. roshevitzii, H. lechleri, and H. procerum, regenerated high numbers of plants from calli....

A novel life cycle arising from leaf segments in plants regenerated from horseradish hairy roots.

Science.gov (United States)

Mano, Y; Matsuhashi, M

1995-03-01

Horseradish (Armoracia rusticana) hairy root clones were established from hairy roots which were transformed with the Ri plasmid in Agrobacterium rhizogenes 15834. The transformed plants, which were regenerated from hairy root clones, had thicker roots with extensive lateral branches and thicker stems, and grew faster compared with non-transformed horseradish plants. Small sections of leaves of the transformed plants generated adventitious roots in phytohormone-free G (modified Gamborg's) medium. Root proliferation was followed by adventitious shoot formation and plant regeneration. Approximately twenty plants were regenerated per square centimeter of leaf. The transformed plants were easily transferable from sterile conditions to soil. When leaf segments of the transformed plants were cultured in a liquid fertilizer under non-sterile conditions, adventitious roots were generated at the cut ends of the leaves. Adventitious shoots were generated at the boundary between the leaf and the adventitious roots and developed into complete plants. This novel life cycle arising from leaf segments is a unique property of the transformed plants derived from hairy root clones.

Magnetic field exposure stiffens regenerating plant protoplast cell walls.

Science.gov (United States)

Haneda, Toshihiko; Fujimura, Yuu; Iino, Masaaki

2006-02-01

Single suspension-cultured plant cells (Catharanthus roseus) and their protoplasts were anchored to a glass plate and exposed to a magnetic field of 302 +/- 8 mT for several hours. Compression forces required to produce constant cell deformation were measured parallel to the magnetic field by means of a cantilever-type force sensor. Exposure of intact cells to the magnetic field did not result in any changes within experimental error, while exposure of regenerating protoplasts significantly increased the measured forces and stiffened regenerating protoplasts. The diameters of intact cells or regenerating protoplasts were not changed after exposure to the magnetic field. Measured forces for regenerating protoplasts with and without exposure to the magnetic field increased linearly with incubation time, with these forces being divided into components based on the elasticity of synthesized cell walls and cytoplasm. Cell wall synthesis was also measured using a cell wall-specific fluorescent dye, and no changes were noted after exposure to the magnetic field. Analysis suggested that exposure to the magnetic field roughly tripled the Young's modulus of the newly synthesized cell wall without any lag.

In vitro embryo rescue and plant regeneration following self ...

African Journals Online (AJOL)

EJIRO

2015-07-08

Jul 8, 2015 ... 2Department of Biological Sciences, College of Natural Sciences, Makerere ... Key words: Cassava, doubled haploids, embryo rescue, plant regeneration, pollen germination, pollen ... breeding as inbred lines are readily tested and used within a ... dominance, allowing the separation of homozygotes from.

In vitro somatic embryogenesis and plant regeneration of cassava.

Science.gov (United States)

Szabados, L; Hoyos, R; Roca, W

1987-06-01

An efficient and reproducible plant regeneration system, initiated in somatic tissues, has been devised for cassava (Manihot esculenta Crantz). Somatic embryogenesis has been induced from shoot tips and immature leaves of in vitro shoot cultures of 15 cassava genotypes. Somatic embryos developed directly on the explants when cultured on a medium containing 4-16 mg/l 2,4-D. Differences were observed with respect to the embryogenic capacity of the explants of different varieties. Secondary embryogenesis has been induced by subculture on solid or liquid induction medium. Long term cultures were established and maintained for up to 18 months by repeated subculture of the proliferating somatic embryos. Plantlets developed from primary and secondary embryos in the presence of 0.1 mg/l BAP, 1mg/l GA3, and 0.01 mg/l 2,4-D. Regenerated plants were transferred to the field, and were grown to maturity.

Plant regeneration system from cotyledons-derived calluses cultures ...

African Journals Online (AJOL)

Administrator

2011-09-26

Sep 26, 2011 ... The objective of this study was to successfully establish plant regeneration system with cotyledons of. Stylosanthes guianensis Sw. cv. 'Reyan 2' as explants. In this study, the following results were obtained; (1) the highest rates of callus induction on medium MS with 3.0 mg L-1 2, 4-D with cotyledons.

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.

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......-propagated shoots and older leaves of greenhouse-grown plants. Immature inflorescences smaller than 2.5 cm produced a higher percentage of embryogenic callus than larger more mature inflorescences. Embryogenic callus derived from immature inflorescences had the highest regeneration capacity. Differences in 2......,4-dichlorophenoxyacetic acid concentrations had no significant effect on callus induction, embryogenic callus formation and plant regeneration....

Plant regeneration of Brassica oleracea subsp. italica (Broccoli) CV ...

African Journals Online (AJOL)

STORAGESEVER

2009-06-03

Jun 3, 2009 ... Department of Agriculture Technology, Faculty of Agriculture, Universiti Putra Malaysia, 43400 Serdang, Selangor Darul. Ehsan, Malaysia. Accepted 20 March, 2009. Hypocotyls and shoot tips were used as explants in in vitro plant regeneration of broccoli (Brassica oleracea subsp.italica) cv. Green Marvel.

Plant regeneration of natural tetraploid Trifolium  Hum pratense L

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HATICE ÇÖLGEÇEN

2008-01-01

Full Text Available The regeneration of natural tetraploid T. pratense, originated from Erzurum-Turkey, is reported in this study. This plant has low seed setting and hard seed problems due to polyploidy. Hypocotyl, cotyledon, apical meristems, epicotyl and young primary leaves were inoculated on MS and PC-L2 media containing different concentrations of BAP and NAA as growth regulators. The best shoot formation has been observed on explants initiated from apical meristem placed on PC-L2 medium that includes 2 mg dm-3 BAP and 1 mg dm-3 NAA. 94.4% of the shoots originated from calli were rooted on PC-L2 medium with 1 mg dm-3 NAA. In vitro organogénesis has been accomplished in the natural tetraploid T. pratense regenerated plants successively transferred to the field

Plant regeneration of Erigeron breviscapus (vant.) Hand. Mazz. and its chromatographic fingerprint analysis for quality control.

Science.gov (United States)

Liu, Chun-Zhao; Gao, Min; Guo, Bin

2008-01-01

An efficient micropropagation system for Erigeron breviscapus (vant.) Hand. Mazz., an important medicinal plant for heart disease, has been developed. Shoot organogenesis occurred from E. breviscapus leaf explants inoculated on a medium supplemented with a combination of plant growth regulators. On average, 17 shoots per leaf explant were produced after 30 days when they were cultured on MS basal salts and vitamin medium containing 5 microM 6-benzylaminopurine (BAP) and 5 microM 1-naphthaleneacetic acid (NAA). All the regenerated shoots formed complete plantlets on a medium containing 2.5-10 microM indole-3-butyric acid (IBA) within 30 days, and 80.2% of the regenerated plantlets survived and grew vigorously in field conditions. Based on the variation in common peaks and the produced amount of the most important bioactive component, scutellarin, a high performance liquid chromatography (HPLC) fingerprinting system was developed for quality control of these micropropagated plants. Chemical constituents in E. breviscapus micropropagated plants varied during plant development from regeneration to maturation, the latter of which showed the most similar phytochemical profile in comparison with mother plants. The regeneration protocol and HPLC fingerprint analysis developed here provided a new approach to quality control of micropropagated plants producing secondary metabolites with significant implications for germplasm conservation.

TDZ-induced plant regeneration in Astragalus cicer L. | Basalma ...

African Journals Online (AJOL)

We developed a regeneration protocol using thidiazuron (TDZ) with a high frequency in vitro root induction in Astragalus cicer. High in vitro germination ratio (75%) for hard-seeds of A. cicer was also achieved. For this, hypocotyl and cotyledon explants were cultured on Murashige and Skoog medium supplemented with ...

Inside out: high-efficiency plant regeneration and Agrobacterium-mediated transformation of upland and lowland switchgrass cultivars.

Science.gov (United States)

Liu, Yan-Rong; Cen, Hui-Fang; Yan, Jian-Ping; Zhang, Yun-Wei; Zhang, Wan-Jun

2015-07-01

Selection of pre-embryogenic callus from a core structure from mature seed-derived callus is the key for high-efficiency plant regeneration and transformation of switchgrass different cultivars. Switchgrass (Panicum virgatum L.) has been identified as a dedicated biofuel crop. For its trait improvement through biotechnological approaches, we have developed a highly efficient plant regeneration and genetic transformation protocol for both lowland and upland cultivars. We identified and separated a pre-embryogenic "core" structure from the seed-derived callus, which often leads to development of highly regenerative type II calluses. From the type II callus, plant regeneration rate of lowland cultivars Alamo and Performer reaches 95%, and upland cultivars Blackwell and Dacotah, 50 and 76%, respectively. The type II callus was also amenable for Agrobacterium-mediated transformation. Transformation efficiency of 72.8% was achieved for lowland cultivar Alamo, and 8.0% for upland cultivar Dacotah. PCR, Southern blot and GUS staining assays were performed to verify the transgenic events. High regenerative callus lines could be established in 3 months, and transgenic plants could be obtained in 2 months after Agrobacterium infection. To our knowledge, this is the first report on successful plant regeneration and recovery of transgenic plants from upland switchgrass cultivars by Agrobacterium-mediated transformation. The method presented here could be helpful in breaking through the bottleneck of regeneration and transformation of lowland and upland switchgrass cultivars and probably other recalcitrant grass crops.

Efficient regeneration of plants from shoot tip explants of ...

African Journals Online (AJOL)

Dendrobium densiflorum Lindl. is one of the horticulturally important orchids of Nepal due to its beautiful yellowish flower and medicinal properties. The present study was carried out for plant regeneration from shoot tip explants of D. densiflorum by tissue culture technique. The shoot tip explants of this species, obtained ...

Plant regeneration from haploid cell suspension-derived protoplasts of Mediterranean rice (Oryza sativa L. cv. Miara).

Science.gov (United States)

Guiderdoni, E; Chaïr, H

1992-11-01

More than 750 plants were regenerated from protoplasts isolated from microspore callus-derived cell suspensions of the Mediterranean japonica rice Miara, using a nurse-feeder technique and N6-based culture medium. The mean plating efficiency and the mean regeneration ability of the protocalluses were 0.5% and 49% respectively. Flow cytometric evaluation of the DNA contents of 7 month old-cell and protoplast suspensions showed that they were still haploid. Contrastingly, the DNA contents of leaf cell nuclei of the regenerated protoclones ranged from 1C to 5C including 60% 2C plants. This was consistent with the morphological type and the fertility of the mature plants. These results and the absence of chimeric plants suggest that polyploidization occurred during the early phase of protoplast culture.

Plant regeneration from protoplasts of Gentiana straminea Maxim

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Shi Guomin

2016-01-01

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%.

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.

Contrasting natural regeneration and tree planting in fourteen North American cities

Science.gov (United States)

David J. Nowak

2012-01-01

Field data from randomly located plots in 12 cities in the United States and Canada were used to estimate the proportion of the existing tree population that was planted or occurred via natural regeneration. In addition, two cities (Baltimore and Syracuse) were recently re-sampled to estimate the proportion of newly established trees that were planted. Results for the...

Study Of Plant Regeneration Potential In Tropical Moist Deciduous Forest In Northern India

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Ashish K Mishra

2013-12-01

Full Text Available Regeneration patterns of species population can address climate change by adaptive evolution or by migrating association to survive in their favorable climate and finally decided to particular forest future. In this paper we examined the status of regeneration potential of tree species in tropical moist deciduous forest at Katerniaghat Wildlife Sanctuary, Northern India. To investigate tree, sapling and seedling population distribution, we examine regeneration status in 145 random plots in study area. Total 74 plant species of 60 genera belonging to 32 families out of which 71 species of trees, 56 of seedlings and 60 of saplings were found in the forest. On the basis of importance value index Mallotus philippensis, Tectona grandis, Shorea robusta, Syzygium cumini and Bombax ceiba have been found as dominant species in the study area. As far as the regeneration status is concerned, the maximum tree species (64% have been found in good regeneration category. Significant variations in species richness and population density, between three life form (i. e. tree, sapling and seedling have been found. In which only three new tree species Prosopis juliflora, Psidium guajava and Morus alba were added in sapling and seedling stage. It is major ecological concern that about 19 % economically important plant species like Madhuca longifolia, Terminalia elliptica, Buchanania cochinchinensis, some Ficus species etc. have been found in poor regeneration phage, whereas about 7% species found in no regeneration categories. International Journal of Environment, Volume-2, Issue-1, Sep-Nov 2013, Pages 153-163 DOI: http://dx.doi.org/10.3126/ije.v2i1.9218

Regeneration of some monocotyledonous plants from subterranean organs in vitro

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Krystyna D. Kromer

2013-12-01

Full Text Available The aim in view was investigation ofthe regenerative potential of rhizomes, bulbs and corms of ten monocotyledonous plant species from four families: Amaryllidaceae (Haemanthus katharinae, Crinum abyssinicum, Leucojum vernum, Araceae (Spathiphyllum wallisii, Iridaceae (Crocus vernus, Iris germanica, Liliaceae (Hosta lancifolia, Muscari racemosum, Scilla laxiflora, Veltheimia viridifolia under conditions of in vitro culture. All the investigated species were capable of buld or, alternatively, bud and root regeneration. Different morphogenetic potential was noted between the particular families. A high regenerative potential under the conditions of culture applied was characteristic for plants of the Liliaceae and Araceae families, it was lower in plants belonging to Amaryllidaceae and lowest in those of the Iridaceae family. Plants from the Liliaceae family exhibited also the highest ability of callus formation, whereas Amaryllidaceae and Iridaceae plants possessed this ability in only a low degree. The influence of growth regulators of the auxin group (NAA, IAA, 2,4-D and of cytokinins (K on the initiation and course of organogenesis was tested. The results of the experiments indicate that auxins in interaction with kinetin gave the highest percentage of regenerating explants and also a large number of buds on the latter. Stimulation of callus tissue was highest under the influence of 2,4-D, and weaker when NAA IAA were used.

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

2014-01-01

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. 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. PMID:25606433

Stimulation effects of γ-irradiation combined with colchicine on callus formation and green plant regeneration in rice anther culture

International Nuclear Information System (INIS)

Jin Wei; Chen Qiufang; Wang Cailian; Lu Yimei

1999-09-01

The ability of callus formation and green plant regeneration was very different for various rice types and varieties in rice anther culture. It was quite effective that rice anthers were irradiated with 10-40 Gy of γ-rays after 30 d incubation on induction medium and calli were treated on differentiation medium contained 10-75 mg/L of colchicine for increase of callus formation and green plant regeneration. Among these treatments, 10 Gy of γ-rats was the best for callus formation, and 20 Gy of γ-rays or 30 mg/L of colchicine was the most favourable for green plant regeneration. The simulation effect of 20 Gy of γ-irradiation combined with 30 mg/L of colchicine on green plant regeneration was much better than that of their separate use in rice anther culture

Regeneration of whole fertile plants from 30,000-y-old fruit tissue buried in Siberian permafrost.

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Yashina, Svetlana; Gubin, Stanislav; Maksimovich, Stanislav; Yashina, Alexandra; Gakhova, Edith; Gilichinsky, David

2012-03-06

Whole, fertile plants of Silene stenophylla Ledeb. (Caryophyllaceae) have been uniquely regenerated from maternal, immature fruit tissue of Late Pleistocene age using in vitro tissue culture and clonal micropropagation. The fruits were excavated in northeastern Siberia from fossil squirrel burrows buried at a depth of 38 m in undisturbed and never thawed Late Pleistocene permafrost sediments with a temperature of -7 °C. Accelerator mass spectrometry (AMS) radiocarbon dating showed fruits to be 31,800 ± 300 y old. The total γ-radiation dose accumulated by the fruits during this time was calculated as 0.07 kGy; this is the maximal reported dose after which tissues remain viable and seeds still germinate. Regenerated plants were brought to flowering and fruiting and they set viable seeds. At present, plants of S. stenophylla are the most ancient, viable, multicellular, living organisms. Morphophysiological studies comparing regenerated and extant plants obtained from modern seeds of the same species in the same region revealed that they were distinct phenotypes of S. stenophylla. The first generation cultivated from seeds obtained from regenerated plants progressed through all developmental stages and had the same morphological features as parent plants. The investigation showed high cryoresistance of plant placental tissue in permafrost. This natural cryopreservation of plant tissue over many thousands of years demonstrates a role for permafrost as a depository for an ancient gene pool, i.e., preexisting life, which hypothetically has long since vanished from the earth's surface, a potential source of ancient germplasm, and a laboratory for the study of rates of microevolution.

The composition and regeneration status of wild food plants in ...

African Journals Online (AJOL)

The composition and regeneration status of wild food plants in Chenene Miombo woodland, Dodoma rural district, Tanzania. VE Tairo. Abstract. No Abstract. Discovery and Innovation Vol. 19 (1&2) 2007: pp. 107-121. Full Text: EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT.

Uniformity of plants regenerated from orange (Citrus sinensis Osb.) protoplasts.

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Kobayashi, S

1987-05-01

Using 25 plants (protoclones) regenerated from orange (Citrus sinensis Osb.) protoplasts, several characters, including leaf and flower morphology, leaf oil, isozyme patterns and chromosome number, were examined. No significant variations in each character were recorded among the protoclones. Uniformity observed among protoclones was identical to that of nucellar seedlings.

Integrated bicarbonate-form ion exchange treatment and regeneration for DOC removal: Model development and pilot plant study.

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Hu, Yue; Boyer, Treavor H

2017-05-15

The application of bicarbonate-form anion exchange resin and sodium bicarbonate salt for resin regeneration was investigated in this research is to reduce chloride ion release during treatment and the disposal burden of sodium chloride regeneration solution when using traditional chloride-form ion exchange (IX). The target contaminant in this research was dissolved organic carbon (DOC). The performance evaluation was conducted in a completely mixed flow reactor (CMFR) IX configuration. A process model that integrated treatment and regeneration was investigated based on the characteristics of configuration. The kinetic and equilibrium experiments were performed to obtain required parameters for the process model. The pilot plant tests were conducted to validate the model as well as provide practical understanding on operation. The DOC concentration predicted by the process model responded to the change of salt concentration in the solution, and showed a good agreement with pilot plant data with less than 10% difference in terms of percentage removal. Both model predictions and pilot plant tests showed over 60% DOC removal by bicarbonate-form resin for treatment and sodium bicarbonate for regeneration, which was comparable to chloride-form resin for treatment and sodium chloride for regeneration. Lastly, the DOC removal was improved by using higher salt concentration for regeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

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.

Partial fast-to-slow conversion of regenerating rat fast-twitch muscle by chronic low-frequency stimulation.

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Pette, Dirk; Sketelj, Janez; Skorjanc, Dejan; Leisner, Elmi; Traub, Irmtrud; Bajrović, Fajko

2002-01-01

Chronic low-frequency stimulation (CLFS) of rat fast-twitch muscles induces sequential transitions in myosin heavy chain (MHC) expression from MHCIIb --> MHCIId/x --> MHCIIa. However, the 'final' step of the fast-to-slow transition, i.e., the upregulation of MHCI, has been observed only after extremely long stimulation periods. Assuming that fibre degeneration/regeneration might be involved in the upregulation of slow myosin, we investigated the effects of CLFS on extensor digitorum longus (EDL) muscles regenerating after bupivacaine-induced fibre necrosis. Normal, non-regenerating muscles responded to both 30- and 60-day CLFS with fast MHC isoform transitions (MHCIIb --> MHCIId --> MHCIIa) and only slight increases in MHCI. CLFS of regenerating EDL muscles caused similar transitions among the fast isoforms but, in addition, caused significant increases in MHCI (to approximately 30% relative concentration). Stimulation periods of 30 and 60 days induced similar changes in the regenerating bupivacaine-treated muscles, indicating that the upregulation of slow myosin was restricted to regenerating fibres, but only during an early stage of regeneration. These results suggest that satellite cells and/or regenerating fast rat muscle fibres are capable of switching directly to a slow program under the influence of CLFS and, therefore, appear to be more malleable than adult fibres.

Mixing of maize and wheat genomic DNA by somatic hybridization in regenerated sterile maize plants.

Science.gov (United States)

Szarka, B.; Göntér, I.; Molnár-Láng, M.; Mórocz, S.; Dudits, D.

2002-07-01

Intergeneric somatic hybridization was performed between albino maize ( Zea mays L.) protoplasts and mesophyll protoplasts of wheat ( Triticum aestivum L.) by polyethylene glycol (PEG) treatments. None of the parental protoplasts were able to produce green plants without fusion. The maize cells regenerated only rudimentary albino plantlets of limited viability, and the wheat mesophyll protoplasts were unable to divide. PEG-mediated fusion treatments resulted in hybrid cells with mixed cytoplasm. Six months after fusion green embryogenic calli were selected as putative hybrids. The first-regenerates were discovered as aborted embryos. Regeneration of intact, green, maize-like plants needed 6 months of further subcultures on hormone-free medium. These plants were sterile, although had both male and female flowers. The cytological analysis of cells from callus tissues and root tips revealed 56 chromosomes, but intact wheat chromosomes were not observed. Using total DNA from hybrid plants, three RAPD primer combinations produced bands resembling the wheat profile. Genomic in situ hybridization (GISH) using total wheat DNA as a probe revealed the presence of wheat DNA islands in the maize chromosomal background. The increased viability and the restored green color were the most-significant new traits as compared to the original maize parent. Other intermediate morphological traits of plants with hybrid origin were not found.

Plant growth regulator interactions in physiological processes for controlling plant regeneration and in vitro development of Tulbaghia simmleri

Czech Academy of Sciences Publication Activity Database

Kumari, A.; Baskaran, P.; Plačková, Lenka; Omámiková, Hana; Nisler, Jaroslav; Doležal, Karel; Van Staden, J.

2018-01-01

Roč. 223, APR (2018), s. 65-71 ISSN 0176-1617 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : Endogenous hormone * Exogenous hormone application * In vitro regeneration * Ornamental and medicinal plant * Physiological process * Tulbaghia simmleri Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 3.121, year: 2016

Antioxidant potential in regenerated tissues of medicinally important atropa accuminata

International Nuclear Information System (INIS)

Khan, F. A.; Abbasi, B. H.; Shinwari, Z. K.; Shah, S. H.

2017-01-01

Due to random exploitation from natural resources, an efficient regeneration system of medicinally important but rare plant species, Atropa acuminata for conservation was inevitable. Leaf explants were incubated on MS medium with different level of various plant growth regulators (PGRs) alone and in combination for callus induction and induced organogenesis. After 4 weeks of culture, callus induction was recorded with the highest frequency with 1.0 mg/l thidiazuron (TDZ) supplement. After 5 weeks of subsequent sub-culturing, optimum shoot induction frequency of 89% was achieved with 1.0 mg/l TDZ and 1.0 mg/l a-naphthaleneacetic acid (NAA) supplement. Highest number of shoots/explant (8.2) were recorded on MS medium with 2.0 mg/l 6-benzyladenine (BA)+1.0 mg/l NAA supplement. Shoots in elongation medium was recorded 5.8 cm long in two medium i.e., 1.0 mg/l TDZ supplement and 1.0 mg/l TDZ+1.0 mg/l NAA supplement. Successful In vitro rooting was induced on MS medium with all applied level of indole butyric acid (IBA). The regenerated shoots with well developed roots were successfully acclimatized in sterilized soil and transferred to greenhouse conditions. Furthermore higher activity for detoxifying DPPH free radical was shown by regenerated shoots in this medicinally important plant species. (author)

Understory Structure and Vascular Plant Diversity in Naturally Regenerated Deciduous Forests and Spruce Plantations on Similar Clear-Cuts: Implications for Forest Regeneration Strategy Selection

Directory of Open Access Journals (Sweden)

ZhiQiang Fang

2014-04-01

Full Text Available The active effect of natural regeneration on understory vegetation and diversity on clear-cut forestlands, in contrast to conifer reforestation, is still controversial. Here we investigated differences in understory vegetation by comparing naturally regenerated deciduous forests (NR and reforested spruce plantations (SP aged 20–40 years on 12 similar clear-cuts of subalpine old-growth spruce-fir forests from the eastern Tibetan Plateau. We found that 283 of the 334 vascular plant species recorded were present in NR plots, while only 264 species occurred in SP plots. This was consistent with richer species, higher cover, and stem (or shoot density of tree seedlings, shrubs, and ferns in the NR plots than in the SP plots. Moreover, understory plant diversity was limited under dense canopy cover, which occurred more frequently in the SP plots. Our findings implied that natural deciduous tree regeneration could better preserve understory vegetation and biodiversity than spruce reforestation after clear-cutting. This result further informed practices to reduce tree canopy cover for spruce plantations or to integrate natural regeneration and reforestation for clear-cuts in order to promote understory vegetation and species diversity conservation.

In vitro regeneration of Salix nigra from adventitious shoots.

Science.gov (United States)

Lyyra, Satu; Lima, Amparo; Merkle, Scott A

2006-07-01

Black willow (Salix nigra Marsh.) is the largest and only commercially important willow species in North America. It is a candidate for phytoremediation of polluted soils because it is fast-growing and thrives on floodplains throughout eastern USA. Our objective was to develop a protocol for the in vitro regeneration of black willow plants that could serve as target material for gene transformation. Unexpanded inflorescence explants were excised from dormant buds collected from three source trees and cultured on woody plant medium (WPM) supplemented with one of: (1) 0.1 mg l(-1) thidiazuron (TDZ); (2) 0.5 mg l(-1) 6-benzoaminopurine (BAP); or (3) 1 mg l(-1) BAP. All plant growth regulator (PGR) treatments induced direct adventitious bud formation from the genotypes. The percentage of explants producing buds ranged from 20 to 92%, depending on genotype and treatment. Although most of the TDZ-treated inflorescences produced buds, these buds failed to elongate into shoots. Buds on explants treated with BAP elongated into shoots that were easily rooted in vitro and further established in potting mix in high humidity. The PGR treatments significantly affected shoot regeneration frequency (P < 0.01). The highest shoot regeneration frequency (36%) was achieved with Genotype 3 cultured on 0.5 mg l(-1) BAP. Mean number of shoots per explant varied from one to five. The ability of black willow inflorescences to produce adventitious shoots makes them potential targets for Agrobacterium-mediated transformation with heavy-metal-resistant genes for phytoremediation.

Management of regenerant effluent waste at reprocessing plant, Tarapur- a new approach

Energy Technology Data Exchange (ETDEWEB)

Chandra, Munish; Bajpai, D D; Mudaiya, Avinash; Varadarajan, N [Power Reactor Fuel Reprocessing Plant, Tarapur (India)

1994-06-01

Power Reactor Fuel Reprocessing (PREFRE) Plant, Tarapur has been processing zircaloy clad spent fuel arising from PHWR namely RAPS and MAPS. The plant has been provided with a water pool to receive and store the irradiated fuel assemblies from the reactor site for an interim period before they are taken up for chop-leach and further reprocessing by PUREX process. This paper highlights the important and innovative modifications like introduction of a cation exchanger for water polishing and using nitric acid as regenerant. The regenerant effluent (nitric acid) is recycled to the main process cells where it is mixed and further treated along with process waste stream. This is a step towards minimising effluent generation. The paper describes the advantages of modified system like operational simplification, manpower, man-rem saving and minimising release of activity to environment. 3 figs., 4 tabs.

Postembryonic organogenesis and plant regeneration from tissues:two sides of the same coin?

Directory of Open Access Journals (Sweden)

Juan ePerianez-Rodriguez

2014-05-01

Full Text Available Plants have extraordinary developmental plasticity as they continuously form organs duringpostembryonic development. In addition they may regenerate organs upon in vitro hormonalinduction. Advances in the field of plant regeneration show that the first steps of de novoorganogenesis through in vitro culture in hormone containing media (via formation of aproliferating mass of cells or callus require root postembryonic developmental programs as wellas regulators of auxin and cytokinin signaling pathways. We review how hormonal regulation isdelivered during lateral root initiation and callus formation. Implications in reprograming, cellfate and pluripotency acquisition are discussed. Finally, we analyze the function of cell-cycleregulators and connections with epigenetic regulation. Future work dissecting plantorganogenesis driven by both endogenous and exogenous cues (upon hormonal induction mayreveal new paradigms of common regulation.

Seismomorphogenesis: a novel approach to acclimatization of tissue culture regenerated plants.

Science.gov (United States)

Sarmast, Mostafa Khoshhal; Salehi, Hassan; Khosh-Khui, Morteza

2014-12-01

Plantlets under in vitro conditions transferred to ex vivo conditions are exposed to biotic and abiotic stresses. Furthermore, in vitro regenerated plants are typically frail and sometimes difficult to handle subsequently increasing their risk to damage and disease; hence acclimatization of these plantlets is the most important step in tissue culture techniques. An experiment was conducted under in vitro conditions to study the effects of shaking duration (twice daily at 6:00 a.m. and 9:00 p.m. for 2, 4, 8, and 16 min at 250 rpm for 14 days) on Sansevieria trifasciata L. as a model plant. Results showed that shaking improved handling, total plant height, and leaf characteristics of the model plant. Forty-eight hours after 14 days of shaking treatments with increasing shaking time, leaf length decreased but proline content of leaf increased. However, 6 months after starting the experiment different results were observed. In explants that received 16 min of shaking treatment, leaf length and area and photosynthesis rate were increased compared with control plantlets. Six months after starting the experiment, control plantlets had 12.5 % mortality; however, no mortality was observed in other treated explants. The results demonstrated that shaking improved the explants' root length and number and as a simple, cost-effective, and non-chemical novel approach may be substituted for other prevalent acclimatization techniques used for tissue culture regenerated plantlets. Further studies with sensitive plants are needed to establish this hypothesis.

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

Science.gov (United States)

Hu, Guang; Xu, Xuehong; Wang, Yuling; Lu, Gao; Feeley, Kenneth J; Yu, Mingjian

2012-01-01

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.

In vitro bulblet regeneration from immature embryos of Muscari ...

African Journals Online (AJOL)

A high frequency bulblet regeneration was achieved for endemic and endangered ornamental plant Muscari azureum using immature embryos. Immature embryos of M. azureum were cultured on callus induction medium consisting of N6 mineral salts and vitamins, 400 mg/L casein + 40 g/L sucrose + 2 g/l L-proline, 2 mg/L ...

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.

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

KAUST Repository

Kumar, Nitish; Vijay Anand, K. G.; Reddy, Muppala P.

2011-01-01

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.

Assessment of carbon sources on in vitro shoot regeneration in tomato

International Nuclear Information System (INIS)

Shah, S.H.; Jan, S.A.

2014-01-01

An innovative approach for in vitro shoot regeneration by both direct and indirect means was developed in three tomato genotypes culturing hypocotyls and leaf discs explants on MS and N6 basal media fortified with various concentrations of carbon sources (sucrose and sorbitol) individually, accumulatively and also in amalgamation with various plant growth regulators. No response of in vitro shoot regeneration was recorded in all the genotypes by the individual application of carbon sources in both MS and N6 basal media. On the other hand, their accumulative effect rapidly enhanced the in vitro shoot regeneration frequency in all the genotypes. The highest shoot organogenesis frequency (100, 99.00 and 97.69%) was recorded in Rio Grande, Roma and Moneymaker, respectively on MS medium fortified with carbon sources (30: 30 g/l) culturing hypocotyls. Supplementation of sucrose: sorbitol (30: 30 g/l) in N6 medium along with different PGRs (0.1 mg/l IAA, 1.0 mg/l ZEA and 2.0 mg/l BAP) produced the highest shoot regeneration frequency (96.33, 92.69 and 88.74%) in Roma, Rio Grande and Moneymaker culturing leaf discs. Our findings suggest an alternative approach as hormone-free protocol for in vitro shoot regeneration in tomato that would save the resources with regard to hormonal costs and time. (author)

Carbon dioxide absorber and regeneration assemblies useful for power plant flue gas

Science.gov (United States)

Vimalchand, Pannalal; Liu, Guohai; Peng, Wan Wang

2012-11-06

Disclosed are apparatus and method to treat large amounts of flue gas from a pulverized coal combustion power plant. The flue gas is contacted with solid sorbents to selectively absorb CO.sub.2, which is then released as a nearly pure CO.sub.2 gas stream upon regeneration at higher temperature. The method is capable of handling the necessary sorbent circulation rates of tens of millions of lbs/hr to separate CO.sub.2 from a power plant's flue gas stream. Because pressurizing large amounts of flue gas is cost prohibitive, the method of this invention minimizes the overall pressure drop in the absorption section to less than 25 inches of water column. The internal circulation of sorbent within the absorber assembly in the proposed method not only minimizes temperature increases in the absorber to less than 25.degree. F., but also increases the CO.sub.2 concentration in the sorbent to near saturation levels. Saturating the sorbent with CO.sub.2 in the absorber section minimizes the heat energy needed for sorbent regeneration. The commercial embodiments of the proposed method can be optimized for sorbents with slower or faster absorption kinetics, low or high heat release rates, low or high saturation capacities and slower or faster regeneration kinetics.

Optimization of soybean (glycine max L.) regeneration for korean cultivars

International Nuclear Information System (INIS)

Phat, P.; Rehman, S. U.; Ju, H. J.; Jung, H. I.

2015-01-01

Tissue culture could provide key insights into the development of transgenic plants, production of good cultivars and secondary metabolites, conservation of endangered plants, and safeguarding of germplasms. In this study, the effects of shoot induction media, explants, cultivars, and phytohormone concentrations on the regeneration efficiency of Korean soybean cultivars were evaluated. Restricted dormancy and poor germination may affect regeneration, depending on the type of germination medium or initiation of phytohormone treatment. Therefore, we analyzed the effects of different germination media containing plant growth regulators, i.e. 6-benzyladenine (BAP), gibberellic acid 3 (GA /sub 3/), and naphthalene acetic acid (NAA), prior to investigating the influences of explant types, media with or without vitamins, cultivars, and different phytohormones (BAP and GA3). A high frequency of germination was observed in Murashige and Skooge (MS) medium with vitamins supplemented with 1 mg L /sup -1/ BAP and 0.25 mg L /sup -1/ GA /sub 3/. Cotyledonary node explants and Gamborg B5 with vitamins supplemented with 1 mg L /sup -1/ BAP and 0.17 mg L /sup -1/ GA /sub 3/ in callus induction medium (CIM) and 1 mg L /sup -1/ BAP in shoot induction medium (SIM) were found to be the most efficient conditions for induction of soybean regeneration, both in callus development and shoot regeneration. Two Korean soybean cultivars, cv. Daepung and Nampung, showed similar development of shoot regeneration efficiency, but significantly different shoot induction times. Therefore, the protocol reported here may be used for further development of regeneration efficiency and can be employed for efficient transformation in soybeans. (author)

Assessment of genetic and epigenetic variation in hop plants regenerated from sequential subcultures of organogenic calli.

Science.gov (United States)

Peredo, Elena L; Revilla, M Angeles; Arroyo-García, Rosa

2006-10-01

Organogenic calli induced from internodal segments were subcultured three times. Regenerated plants obtained from each subculture were analysed by molecular methods. No major genetic rearrangements were detected in the callus-derived plants since none of the amplified fragment-length polymorphism (AFLP) loci were found to be polymorphic. However, epigenetic changes due to a demethylation process were detected by methylation-sensitive amplified polymorphism (MSAP) technique. The results allowed inference of the possible relationship among the plants derived from different calli subcultures and the in vitro control. The plants recovered from the first and second callus subcultures clustered with the in vitro control pools in the phenogram while the regenerants from the third callus subculture showed the highest genetic distance with the controls. This is the first study reporting data about the genetic stability of callus-derived Humulus lupulus L. plants.

Assessment of silver nitrate on callus induction and in vitro shoot regeneration in tomato (solanum lycopersicum mill.)

International Nuclear Information System (INIS)

Shah, S.H.; Ali, S.; Jan, S.A.

2014-01-01

In vitro morphogenesis is greatly influenced by a gaseous plant growth regulator (ethylene). The effect of silver nitrate (AgNO/sub 3/) and different plant growth regulators were assessed on callus induction, In vitro shoot regeneration and multiple primordial shoots per explant in tomato. The maximum callus induction frequency was recorded culturing hypocotyls, while In vitro shoot regeneration frequency and the number of primordial shoots per explant were significantly higher when leaf discs were used as explants. The callus induction frequency was improved by the supplementation of 10-15 mg/l AgNO/sub 3/ in MS basal media along with 2.0 mg/l IAA, 2.5 mg/l BAP and yielded the highest callus induction frequency (91.33%) in cv. Rio Grande, followed by Roma (88.33%) and Moneymaker (82.66%). Similarly, the highest In vitro shoot regeneration frequency (96.66, 92.66 and 90%) was recorded in Rio Grande, Roma and Moneymaker on MS media fortified with 0.1 mg/l IAA, 1.0 mg/l ZEA and 2.0 mg/l BAP along with 8-10 mg/l AgNO/sub 3/. AgNO/sub 3/ also had promotive effect on induction of multiple shoots per explant. These findings indicate that ethylene is linked with the suppression of In vitro morphogenesis in tomato and AgNO3 interacts with ethylene and enhances callus induction and In vitro shoot regeneration in tomato. (author)

Regeneration of the cold trap of the PEC mechanism testing plant

International Nuclear Information System (INIS)

Caponetti, R.; Petrazzuolo, F.

1984-01-01

Experimentation on prototypes of PEC reactor blocking mechanisms is presently in course at Casaccia Cre in the experimental engineering division of the fast reactor department. After a brief description of the experimental cycle of the components, this repor shows the design criteria of a selected method for the regeneration of mechenism testing plant cold trap

High-frequency dual mode pulsed wave Doppler imaging for monitoring the functional regeneration of adult zebrafish hearts

OpenAIRE

Kang, Bong Jin; Park, Jinhyoung; Kim, Jieun; Kim, Hyung Ham; Lee, Changyang; Hwang, Jae Youn; Lien, Ching-Ling; Shung, K. Kirk

2015-01-01

Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 ...

Light requirement for shoot regeneration in horseradish hairy roots.

Science.gov (United States)

Saitou, T; Kamada, H; Harada, H

1992-08-01

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.

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.

Influence of gamma ray treatment on in vitro regenerated plants of Atropa Belladonna L

International Nuclear Information System (INIS)

Toth, E.; Onisei, T.; Amariei, D.

1994-01-01

Regenerated plants were obtained through callus organogenesis after gamma ray treatment with 1 to 9 Krad doses. Vigorous shoots were regenerated on MS (1962) medium supplemented with 2 mg/l 6-benzylaminopurine. Shoot growth was inhibited with increasing irradiation doses. At 2 Krad dose root Primordia were observed after 18 days while 32 days were necessary to produce roots at 7-9 Krad. As compared to the control, the survival percent during acclimatization was 80 to 85% at 2-3 Krad, 65-70% at 4-6 Krad and 60-62% at 7-9 Krad. Approximately 330 plants were transferred to field conditions. Morphological and biochemical parameters were measured and the data were statistically processed. Plant height was negatively influenced by higher doses of irradiation. A chlorophyll deficient plant arose from the 6 Krad treatment which showed a different pattern of isoperoxidase and isoesterase as compared to the control. A yellow-flower mutant was obtained from the 3 Krad treatment and is assumed to be Atropa belladonna var. Flava Pater. (author)

Effect of in vitro mutagenesis on plant regeneration in Citrus aurantifolia S

International Nuclear Information System (INIS)

Srivastava, R.K.; Sandhu, A.S.; Gosal, S.S.

2001-01-01

Callus was induced from different explants excised from in vitro raised seedlings on MS medium enriched with naphthalene acetic acid (NAA) (10 mg/l) and kinetin (0.2 mg/l). The cultures were maintained on the same media for 30 days. Part of the 30-day-old calli were exposed to gamma radiation (5 and 10 Gy) and the rest were treated with ethyl methanesulphonate (EMS) (0.1 to 0.4%) for 8 hours. All the treated calli were immediately transferred to regeneration medium [1/2 MS+Benzyl Amino Purine (BAP) (5 mg/l)] along with the untreated control. The cultures were maintained under conditions of 25±2 deg. C, 16/8 hours day and night regime and 2500-3000 lux light intensity. The results indicated a significant effect of mutagenic agent on callus regeneration and regenerants' morphological features. The same phenomenon was observed in Triticum aestivum and Zea mays. Regenerated mutants showed variation in morphological traits like, plant height, leaf length and breadth. Moreover, the mutants are being screened for resistance against citrus canker. However, the genetic origin of the mutants has not been determined

Study on regeneration effect and mechanism of high-frequency ultrasound on biological activated carbon.

Science.gov (United States)

Sun, Zhehao; Liu, Cheng; Cao, Zhen; Chen, Wei

2018-06-01

High frequency ultrasonic radiation technology was developed as a novel and efficient means of regenerating spent biological activated carbon (BAC) used in drinking water treatment plants (DWTPs). The results of this study indicated that high frequency ultrasonic treatment could recover the spent BAC, to some extent, with the following optimal conditions: a frequency of 400 kHz, sonication power of 60 W, water temperature of 30 °C, and sonication time of 6 min. Under the above conditions, the iodine value increased from 300 mg/g to 409 mg/g, the volume of total pores and micropores increased from 0.2600 cm 3 /g and 0.1779 cm 3 /g to 0.3560 cm 3 /g and 0.2662 cm 3 /g, respectively; the specific surface area of micropores and the mean pore diameter expanded from 361.15 m 2 /g and 2.0975 nm to 449.92 m 2 /g and 2.1268 nm, respectively. The biological activity increased from 0.0297 mgO 2 /gC·h to 0.0521 mgO 2 /gC·h, while the biomass decreased from 203 nmolP/gC to 180 nmolP/gC. The results of high throughput 16S rRNA gene amplicon sequencing showed that microorganisms such as Clostridia and Nitrospira were markedly decreased due to high frequency ultrasound. The method used in this study caused the inhibition of certain carbon-attached microbials resulting in a negative effect on the removal rate of ammonia-N during the initial stage of the long-term reuse operation. The removal of UV254 and atrazine were restored from 8.1% and 55% to 21% and 76%, respectively. Copyright © 2018 Elsevier B.V. All rights reserved.

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

African Journals Online (AJOL)

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2009-12-15

Dec 15, 2009 ... Ki-Won Lee, Gi Jun Choi, Ki-Yong Kim, Hee Chung Ji, Hyung Soo Park, Sei Hyung Yoon and ... Gramineae family plants (Ha et al., 2001; Dong and Qu, ..... Lee SH, Ahsan N, Lee KW, Kim DH, Lee DG, Kwak SS, Kwon SY, ...

Shoot Organogenesis and Plant Regeneration from Leaf Explants of Lysionotus serratus D. Don

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Qiansheng Li

2013-01-01

Full Text Available The gesneriaceous perennial plant, Lysionotus serratus, has been used in traditional Chinese medicine. It also has a great development potential as an ornamental plant with its attractive foliage and beautiful flowers. An efficient propagation and regeneration system via direct shoot organogenesis from leaf explant was established in this study. High active cytokinin (6-benzyladenine (BA or thidiazuron (TDZ was effective for direct organogenesis of initial induction. Murashige and Skoog (MS growth media containing 0.5 mg L−1 BA alone or with combination of 0.1 mg L−1  α-Naphthaleneacetic acid (NAA were the most effective for shoot proliferation. High BA concentration (1.0 mg L−1 in the media caused high percentage of vitrified shoots though they introduced high shoot proliferation rate. Histological observation indicated that adventitious shoot regeneration on the medium containing 0.5 mg L−1 BA alone occurred directly from leaf epidermal cells without callus formation. Regenerated shoots rooted well on medium containing half-strength MS medium with 0.5 mg L−1 indole-3-butyric acid (IBA and indole-3-acetic acid (IAA, and the plantlets successfully acclimatized and grew vigorously in the greenhouse with a 94.2% and 92.1% survival rate.

Post-fire regeneration in a Mediterranean pine forest with historically low fire frequency

Science.gov (United States)

Buhk, Constanze; Götzenberger, Lars; Wesche, Karsten; Gómez, Pedro Sánchez; Hensen, Isabell

2006-11-01

Species of Mediterranean vegetation are known to regenerate directly after fire. The phenomenon of autosuccession (direct regeneration) has been found to be often combined with an increase of species richness during the first years after fire due to the high abundance of short-lived herbaceous plants facilitated by plentiful nutrients and light. The high degree of vegetation resilience, which is expressed in terms of autosuccession, has been explained by the selective pressure of fire in historic times. According to existing palaeoecological data, however, the Pinus halepensis forests in the Ricote Mountains (Province of Murcia, SE Spain) did not experience substantial fire impact before the presence of man nor are they especially fire-prone today. Therefore, we studied post-fire regeneration to find out if direct succession is present or if species from pre-fire vegetation are absent during the post-fire regeneration stages. Patterns of succession were deduced from observations made in sample plots on sites of a known regeneration age as well as in adjacent unburnt areas. The results of the vegetation analyses, including a Detrended Correspondence Analysis, indicate that Pinus halepensis forest regeneration after fire resembles autosuccession. As regards the presence of woody species, there is a high percentage similarity on north (83%) and south (70%) facing slopes during the first year after fire vs. reference areas which is due, for example, to direct regeneration of the resprouting Quercus coccifera or seeders like Pinus halepensis or Fumana laevipes. However, if herbaceous species are included in the comparison, the similarity on north-facing sites decreases (to 53%) with the presence of additional species, mainly ruderals like Anagallis arvensis or Reseda phyteuma, and even woody species on the burnt plots. This effect indicates "enhanced autosuccession", which was not found on south-facing sites where overall species richness was very high irrespective of

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

High-frequency electrical stimulation can be a complementary therapy to promote nerve regeneration in diabetic rats.

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Chia-Hong Kao

Full Text Available The purpose of this study was to evaluate whether 1 mA of percutaneous electrical stimulation (ES at 0, 2, 20, or 200 Hz augments regeneration between the proximal and distal nerve stumps in streptozotocin diabetic rats. A10-mm gap was made in the diabetic rat sciatic nerve by suturing the stumps into silicone rubber tubes. Normal animals were used as the controls. Starting 1 week after transection, ES was applied between the cathode placed at the distal stump and the anode at the proximal stump every other day for 3 weeks. At 4 weeks after surgery, the normal controls and the groups receiving ES at 20, and 200 Hz had a higher success percentage of regeneration compared to the ES groups at 0 and 2 Hz. In addition, quantitative histology of the successfully regenerated nerves revealed that the groups receiving ES at a higher frequency, especially at 200 Hz, had a more mature structure with more myelinated fibers compared to those in the lower-frequency ES groups. Similarly, electrophysiology in the ES group at 200 Hz showed significantly shorter latency, larger amplitude, larger area of evoked muscle action potentials and faster conduction velocity compared to other groups. Immunohistochemical staining showed that ES at a higher frequency could significantly promote calcitonin gene-related peptide expression in lamina I-II regions in the dorsal horn and recruit a higher number of macrophages in the diabetic distal sciatic nerve. The macrophages were found that they could stimulate the secretion of nerve growth factor, platelet-derived growth factor, and transforming growth factor-β in dissected sciatic nerve segments. The ES at a higher frequency could also increase cutaneous blood flow in the ipsilateral hindpaw to the injury. These results indicated that a high-frequency ES could be necessary to heal severed diabetic peripheral nerve with a long gap to be repaired.

Parameters affecting frequency of CRISPR/Cas9 mediated targeted mutagenesis in rice.

Science.gov (United States)

Mikami, Masafumi; Toki, Seiichi; Endo, Masaki

2015-10-01

Frequency of CRISPR/Cas9-mediated targeted mutagenesis varies depending on Cas9 expression level and culture period of rice callus. Recent reports have demonstrated that the CRISPR/Cas9 system can function as a sequence-specific nuclease in various plant species. Induction of mutation in proliferating tissue during embryogenesis or in germline cells is a practical means of generating heritable mutations. In the case of plant species in which cultured cells are used for transformation, non-chimeric plants can be obtained when regeneration occurs from mutated cells. Since plantlets are regenerated from both mutated and non-mutated cells in a random manner, any increment in the proportion of mutated cells in Cas9- and guide RNA (gRNA)-expressing cells will help increase the number of plants containing heritable mutations. In this study, we examined factors affecting mutation frequency in rice calli. Following sequential transformation of rice calli with Cas9- and gRNA- expression constructs, the mutation frequency in independent Cas9 transgenic lines was analyzed. A positive correlation between Cas9 expression level and mutation frequency was found. This positive relationship was observed regardless of whether the transgene or an endogenous gene was used as the target for CRISPR/Cas9-mediated mutagenesis. Furthermore, we found that extending the culture period increased the proportion of mutated cells as well as the variety of mutations obtained. Because mutated and non-mutated cells might proliferate equally, these results suggest that a prolonged tissue culture period increases the chance of inducing de novo mutations in non-mutated cells. This fundamental knowledge will help improve systems for obtaining non-chimeric regenerated plants in many plant species.

The IPRP (Integrated Pyrolysis Regenerated Plant) technology: From concept to demonstration

International Nuclear Information System (INIS)

D’Alessandro, Bruno; D’Amico, Michele; Desideri, Umberto; Fantozzi, Francesco

2013-01-01

Highlights: ► IPRP technology development for distributed conversion of biomass and wastes. ► IPRP demonstrative unit combines a rotary kiln pyrolyzer to a 80 kWe microturbine. ► Main performances and critical issues are pointed out for different residual fuels. -- Abstract: The concept of integrated pyrolysis regenerated plant (IPRP) is based on a Gas Turbine (GT) fuelled by pyrogas produced in a rotary kiln slow pyrolysis reactor, where waste heat from GT is used to sustain the pyrolysis process. The IPRP plant provides a unique solution for microscale (below 250 kW) power plants, opening a new and competitive possibility for distributed biomass or wastes to energy conversion systems. The paper summarizes the state of art of the IPRP technology, from preliminary numerical simulation to pilot plant facility, including some new available data on pyrolysis gas from laboratory and pilot plants.

Plant regeneration from cotyledons of mature soybean (Glycine max L.) Wilis cultivar using gamma rays

International Nuclear Information System (INIS)

Hutabarat, D.; Ratna, R.

1999-01-01

Soybean Wilis cultivar was efficiently regenerated in vitro via somatic embryogenesis. Cotyledonary explants were excised from mature germinating seeds. Seeds were germinated on agar solution and on B5 medium enriched with 5 ppm BA, 0.25 ppm BA, 0.25 ppm IBA and 500 ppm casein hydrolyzate. Cotyledonary nodes from both germinating seeds were excised and cultured on B5 medium enriched with 5 ppm BA, 0.25 ppm IBA and 500 ppm casein hydrolyzate. Age of seedlings had a remarkable influence on shoot regeneration. Cotyledon from seeds germinated on agar solution with light gave better result in shoot regeneration compare with those germinated in darkness. The highest number of regenerants per explants (5 shoots) was produced by cotyledon from seeds germinated on B5 medium enriched with 5 ppm IBA and 500 ppm casein hydrolyzate in darkness. The seeds of soybean were exposed to gamma-rays doses 10 Gy then germinated on B5 medium enriched with 5 ppm BA, 0.25 ppm IBA and 500 ppm casein hydrolyzate did not improve the number of plant regeneration. Only 5-day-old seedlings from seeds were exposed to gamma-rays dose 30 Gy could improve the number of shoot regeneration, one of the cotyledonary node treated produced 21 regeneration shoots

Improved efficiency of plant regeneration from protoplasts of eggplant Solanum melongena L.

Science.gov (United States)

Guri, A; Izhar, S

1984-12-01

Eggplant (Solanum melongena L.) mesophyll protoplasts were obtained from in vitro growing plants of line 410 and cv. 'Classic'. Relatively high (15%) plating efficiency was achieved using petri dishes with alternate quadrants containing reservoir medium (R medium + 1% activated charcoal) and culture medium. Shoot regeneration occurred within 6 weeks following initiation of protoplast culture.

Effect of 60Co γ-rays irradiation on plant regeneration from callus of sea dallisgrass (paspalum vaginatum Sw.)

International Nuclear Information System (INIS)

Ye Xiaoqing; She Jianming; Wang Songfeng; Zhang Xu; Liang Liufang; Dong Mingqiang; Wu Yingying

2010-01-01

The pellet embryonic calli of Paspalum vagiantum Sw. cv. Adalay were used for 60 Co γ-rays irradiation. In the callus subculture medium with 2, 4-D 2.0 mg /L and BAP 0.05 mg /L, calli were irradiated at the dose rate 1 Gy /min of 60 Co γ-rays. Results showed that the rate of shoot regeneration was from 94% to 85% when calli irradiated with 20 ∼ 50 Gy; the rate of shoot regeneration was from 76% to 30%, and the rate of plant regeneration was from 44.5% to 8.7% between 60 ∼ 80 Gy. By 60 Gy of 60 Co γ-rays irradiation, the rate of shoot regeneration was about 76% in the differentiation medium with BAP 2.0 mg /L, and the relative rate of plant regeneration was 44.5% in the rooting medium with NAA 0.5 mg /L. The result of sequence-related amplified polymorphism (SRAP) markers analysis showed that the specific SRAP markers were associated with the somatic mutants. The mutation technique of 60 Co γ-rays has been established in the somatic cell of Paspalum vaginatum Sw. (authors)

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.

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.

Effects of mutagens on somatic embryogenesis and plant regeneration in groundnut

International Nuclear Information System (INIS)

Muthusamy, A.; Vasanth, K.; Sivasankari, D.; Chandrasekar, B.R.; Jayabalan, N.

2007-01-01

The embryogenic calli (EC) were obtained from hypocotyl explants of groundnut (Arachis hypogaea L.) cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D) in combination with 0.5 mg dm −3 6-benzylaminopurine (BAP). The EC were exposed to γ-radiation (10–50 Gy) or treated with 1–5 mM of ethyl methane sulphonate (EMS) or sodium azide (SA). The mutated EC were subcultured on embryo induction medium containing 20 mg dm −3 2,4-D. Somatic embryos (SE) developed from these calli were transferred to MS medium supplemented with BAP (2.0 mg dm −3 ) and 0.5 mg dm −3 2,4-D for maturation. The well-developed embryos were cultured on germination medium consisting of MS salts with 2.0 mg dm −3 BAP and 0.25 mg dm −3 naphthaleneacetic acid (NAA). Well-developed plantlets were transferred for hardening and hardened plants produced normal flowers and set viable seeds. The fresh mass of the EC, mean number of SE per explant and regeneration percentage were higher at lower concentrations of mutagens (up to 30 Gy/3 mM). Some abnormalities in regenerated plants were observed, especially variations in leaf shape. (author)

Plants regeneration of a papaya hybrid (IBP 42-99 from callus obtained from apexes of in vitro plants.

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Jorge Gallardo Colina

2004-07-01

Full Text Available In Cuba there realizes innumerable efforts to increase the food production and especially the fruit trees Inside which the papaya has great importance. In this sense studies are realized to obtain plants resistant to virus that they need of tools that they support and increase the indexes of obtaining transgenic line in the events of transformation specifically in a papaya hybrid. As main objective was to develop a protocol for the regeneration of plants of papaya hybrid from callus obtained of in vitro plant apexes.plan to develop a tool that supports and increases the indexes of obtaining line transgenic in the events of transformation in a hybrid of papaya.In vitro plants of the hybrid IBP 42-99 were used as plant material. The culture medium Nitsh and Nitsh was used and the growth regulators that permitted the obtaining of the best callus with embryogenic structures were studied, and also, the concentrations in which they were more efficient were adjusted. The capacity of callus formation from different parts of the stem of the in vitro plants was studied. Different culture medium for the regeneration of papaya plants from the obtained callus was studied. It was possible to obtain callus by combining 6-BAP with ANA and AIA. The best results are obtained when segments from in vitro plants shoot, 1 cm length from the meristem, were used. Also, by eliminating the meristem in the apexes, an increase in the callus formation capacity of the explant was achieved. Plants were obtained from callus using the culture medium MS supplement with 0.09mg.l-1 of AIA, 0.01mg.l-1 of AG3 and 2mg.l-1 of Zeatin and the best percentage was achieved with the callus coming from the treatments with less concentration of 6-BAP and AIA. Key words: culture medium, micropropagation, organogenesis, segments

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

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

Science.gov (United States)

Fayos, Oreto; Vallés, María P; Garcés-Claver, Ana; Mallor, Cristina; Castillo, Ana M

2015-01-01

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 2-3 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 four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis

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

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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

High-frequency dual mode pulsed wave Doppler imaging for monitoring the functional regeneration of adult zebrafish hearts

Science.gov (United States)

Kang, Bong Jin; Park, Jinhyoung; Kim, Jieun; Kim, Hyung Ham; Lee, Changyang; Hwang, Jae Youn; Lien, Ching-Ling; Shung, K. Kirk

2015-01-01

Adult zebrafish is a well-known small animal model for studying heart regeneration. Although the regeneration of scars made by resecting the ventricular apex has been visualized with histological methods, there is no adequate imaging tool for tracking the functional recovery of the damaged heart. For this reason, high-frequency Doppler echocardiography using dual mode pulsed wave Doppler, which provides both tissue Doppler (TD) and Doppler flow in a same cardiac cycle, is developed with a 30 MHz high-frequency array ultrasound imaging system. Phantom studies show that the Doppler flow mode of the dual mode is capable of measuring the flow velocity from 0.1 to 15 cm s−1 with high accuracy (p-value = 0.974 > 0.05). In the in vivo study of zebrafish, both TD and Doppler flow signals were simultaneously obtained from the zebrafish heart for the first time, and the synchronized valve motions with the blood flow signals were identified. In the longitudinal study on the zebrafish heart regeneration, the parameters for diagnosing the diastolic dysfunction, for example, E/Em < 10, E/A < 0.14 for wild-type zebrafish, were measured, and the type of diastolic dysfunction caused by the amputation was found to be similar to the restrictive filling. The diastolic function was fully recovered within four weeks post-amputation. PMID:25505135

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.

Effects of soil drought stress on plant regeneration efficiency and endogenous hormone levels of immature embryos in wheat (Triticum aestivum L.)

International Nuclear Information System (INIS)

Bie, X.; Wang, K.; Liu, C.; Du, L.

2017-01-01

In this study, the water supply in soil for wheat mother donor plants was controlled, leading to drought stress conditions, and the relative soil water content (RSWC) was measured in different soil depths. The immature embryos of common wheat (Triticum aestivum L.) 13 days post anthesis (DPA) were used to test regeneration capacity. The accumulation of the plant growth regulators (PGRs) including abscisic acid (ABA), indole-3-acetic acid (IAA), and hydrogen peroxide (H2O2) in the wheat embryos grown under the two conditions was measured. The results indicated that RSWC difference between the drought treatment and the irrigated control was more than 13% at the various soil depths, with the maximum difference was observed at 40 cm depth. Tissue culture evaluation showed that the plant regeneration efficiency of the immature embryos grown under drought stress treatment was significantly higher than that of the tissues grown under the control condition. Assay for PGR found that the drought stress caused obviously increased concentration of endogenous ABA and H2O2, and slightly decreased level of IAA in the target tissues. Therefore, it seems that the concentration of endogenous ABA, IAA, and H2O2 in immature wheat embryos is very important in regeneration capacity. Drought stress can improve the regeneration capacity by changing the levels of ABA, IAA, and H2O2. Our results would be helpful to efficient development of genetically modified wheat plants through improvement of regeneration via manipulating the endogenous PGRs. (author)

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.

Improvement of efficient in vitro regeneration potential of mature callus induced from Malaysian upland rice seed (Oryza sativa cv. Panderas).

Science.gov (United States)

Mohd Din, Abd Rahman Jabir; Iliyas Ahmad, Fauziah; Wagiran, Alina; Abd Samad, Azman; Rahmat, Zaidah; Sarmidi, Mohamad Roji

2016-01-01

A new and rapid protocol for optimum callus production and complete plant regeneration has been assessed in Malaysian upland rice (Oryza sativa) cv. Panderas. The effect of plant growth regulator (PGR) on the regeneration frequency of Malaysian upland rice (cv. Panderas) was investigated. Mature seeds were used as a starting material for callus induction experiment using various concentrations of 2,4-D and NAA. Optimal callus induction frequency at 90% was obtained on MS media containing 2,4-D (3 mg L(-1)) and NAA (2 mg L(-1)) after 6 weeks while no significant difference was seen on tryptophan and glutamine parameters. Embryogenic callus was recorded as compact, globular and light yellowish in color. The embryogenic callus morphology was further confirmed with scanning electron microscopy (SEM) analysis. For regeneration, induced calli were treated with various concentrations of Kin (0.5-1.5 mg L(-1)), BAP, NAA and 0.5 mg L(-1) of TDZ. The result showed that the maximum regeneration frequency (100%) was achieved on MS medium containing BAP (0.5 mg L(-1)), Kin (1.5 mg L(-1)), NAA (0.5 mg L(-1)) and TDZ (0.5 mg L(-1)) within four weeks. Developed shoots were successfully rooted on half strength MS free hormone medium and later transferred into a pot containing soil for acclimatization. This cutting-edge finding is unique over the other existing publishable data due to the good regeneration response by producing a large number of shoots.

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.

High frequency plant regeneration from leaf explants derived callus of evening primrose (oenothera biennis)

International Nuclear Information System (INIS)

Ghauri, E.G.; Shafi, N.; Ghani, S.; Fatima, A.

2008-01-01

The seeds of Evening primrose were aseptically grown and leaf explants were used for establishment of callus culture. The Excellent growth in callus biomass was achieved on MS medium supplemented with 2, 4, -D and TDZ. For optimal growth of bud and shoot regeneration, fortification of IAA along with TDZ, or BAP was found to be essential. Rooting (70%) could be inducted on hormone free MS-medium. This percentage improved to 98 when NAA was added to the medium. The plantlets thus obtained were transferred to the field successfully after passing through the process of hardening. (author)

Effect of γ-ray irradiation on in vitro culture and plant regeneration of alfalfa

International Nuclear Information System (INIS)

Zhang Xiaodong; Lin Tingan

1992-01-01

60 Co γ-ray irradiation ranged 0-16 kR was used to treat the cotyledons and hypocotyls of 5 cultivars of a alfalfa (Medicago sativa L.). The effects of irradiation on the frequency of callus, fresh weight of callus, the frequency of somatic embryo induction and plantlet regeneration were studied. The results showed as follows: the radiosensitivities of cotyledon was significantly higher than that of hypocotyl. Exposure of 2 kR could improve the growth of callus, embryogenesis and plantlet regeneration at various levels. Exposure of 12 kR completely inhibited the callus formation from explants of cotyledon. Callus from two cultivars, England 648 and Jining alfalfa, were irradiated with 0-8 kR. The results showed that exposure below 2 kR could promote the growth of callus and the formation of somatic embryo at different levels. The exposure of 8 kR had the effect of lethal. The optimum exposure for genetic improvement of alfalfa in vitro by inducing mutation was considered to be 4-6 kR

Wide variety of flower-color and -shape mutants regenerated from leaf cultures irradiated with ion beams

International Nuclear Information System (INIS)

Okamura, M.; Yasuno, N.; Ohtsuka, M.; Tanaka, A.; Shikazono, N.; Hase, Y.

2003-01-01

The efficiency of ion-beam irradiation combined with tissue culture in obtaining floral mutants was investigated and compared with those of gamma rays and X-rays in carnation. Leaf segments of carnation plants in vitro were irradiated with the 220 MeV carbon ions, and cultured till the shoot regenerated. The carbon ion had the highest effect in reducing the regeneration frequency, and the RBE value with respect to gamma-rays was four. The higher mutation frequency and the wider mutation spectrum were obtained in plants irradiated with the carbon ions than low LET radiations. Three new carnation varieties developed by ion-beam irradiation were applied for the registration of the Japanese Ministry of Agriculture, Forestry and Fisheries. The results indicate that ion beam irradiation could induce wide variety of flower-color and -shape mutants, and that the combined method of ion-beam irradiation with tissue culture is useful to obtain the commercial varieties in a short time

Methods for tornado frequency calculation of nuclear power plant

International Nuclear Information System (INIS)

Liu Haibin; Li Lin

2012-01-01

In order to take probabilistic safety assessment of nuclear power plant tornado attack event, a method to calculate tornado frequency of nuclear power plant is introduced based on HAD 101/10 and NUREG/CR-4839 references. This method can consider history tornado frequency of the plant area, construction dimension, intensity various along with tornado path and area distribution and so on and calculate the frequency of different scale tornado. (authors)

Succession influences wild bees in a temperate forest landscape: the value of early successional stages in naturally regenerated and planted forests.

Science.gov (United States)

Taki, Hisatomo; Okochi, Isamu; Okabe, Kimiko; Inoue, Takenari; Goto, Hideaki; Matsumura, Takeshi; Makino, Shun'ichi

2013-01-01

In many temperate terrestrial forest ecosystems, both natural human disturbances drive the reestablishment of forests. Succession in plant communities, in addition to reforestation following the creation of open sites through harvesting or natural disturbances, can affect forest faunal assemblages. Wild bees perform an important ecosystem function in human-altered and natural or seminatural ecosystems, as they are essential pollinators for both crops and wild flowering plants. To maintain high abundance and species richness for pollination services, it is important to conserve and create seminatural and natural land cover with optimal successional stages for wild bees. We examined the effects of forest succession on wild bees. In particular, we evaluated the importance of early successional stages for bees, which has been suspected but not previously demonstrated. A range of successional stages, between 1 and 178 years old, were examined in naturally regenerated and planted forests. In total 4465 wild bee individuals, representing 113 species, were captured. Results for total bees, solitary bees, and cleptoparasitic bees in both naturally regenerated and planted conifer forests indicated a higher abundance and species richness in the early successional stages. However, higher abundance and species richness of social bees in naturally regenerated forest were observed as the successional stages progressed, whereas the abundance of social bees in conifer planted forest showed a concave-shaped relationship when plotted. The results suggest that early successional stages of both naturally regenerated and conifer planted forest maintain a high abundance and species richness of solitary bees and their cleptoparasitic bees, although social bees respond differently in the early successional stages. This may imply that, in some cases, active forest stand management policies, such as the clear-cutting of planted forests for timber production, would create early successional

Succession influences wild bees in a temperate forest landscape: the value of early successional stages in naturally regenerated and planted forests.

Directory of Open Access Journals (Sweden)

Hisatomo Taki

Full Text Available In many temperate terrestrial forest ecosystems, both natural human disturbances drive the reestablishment of forests. Succession in plant communities, in addition to reforestation following the creation of open sites through harvesting or natural disturbances, can affect forest faunal assemblages. Wild bees perform an important ecosystem function in human-altered and natural or seminatural ecosystems, as they are essential pollinators for both crops and wild flowering plants. To maintain high abundance and species richness for pollination services, it is important to conserve and create seminatural and natural land cover with optimal successional stages for wild bees. We examined the effects of forest succession on wild bees. In particular, we evaluated the importance of early successional stages for bees, which has been suspected but not previously demonstrated. A range of successional stages, between 1 and 178 years old, were examined in naturally regenerated and planted forests. In total 4465 wild bee individuals, representing 113 species, were captured. Results for total bees, solitary bees, and cleptoparasitic bees in both naturally regenerated and planted conifer forests indicated a higher abundance and species richness in the early successional stages. However, higher abundance and species richness of social bees in naturally regenerated forest were observed as the successional stages progressed, whereas the abundance of social bees in conifer planted forest showed a concave-shaped relationship when plotted. The results suggest that early successional stages of both naturally regenerated and conifer planted forest maintain a high abundance and species richness of solitary bees and their cleptoparasitic bees, although social bees respond differently in the early successional stages. This may imply that, in some cases, active forest stand management policies, such as the clear-cutting of planted forests for timber production, would create

[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.

Evaluation of drug uptake and deactivation in plant: Fate of albendazole in ribwort plantain (Plantago laceolata) cells and regenerants.

Science.gov (United States)

Stuchlíková Raisová, Lucie; Podlipná, Radka; Szotáková, Barbora; Syslová, Eliška; Skálová, Lenka

2017-07-01

Albendazole (ABZ) is a benzimidazole anthelmintic widely used especially in veterinary medicine. Along with other drugs, anthelmintics have become one of a new class of micro-pollutants that disturb the environment but the information about their fate in plants remains limited. The present study was designed to test the uptake and biotransformation of ABZ in the ribwort plantain (Plantago lancelota), a common meadow plant, which can come into contact with this anthelmintic through the excrements of treated animals in pastures. Two model systems were used and compared: cell suspensions and whole plant regenerants. In addition, time-dependent changes in occurrence of ABZ and its metabolites in roots, basal parts of the leaves and tops of the leaves were followed up. Ultrahigh-performance liquid chromatography coupled with high mass accuracy tandem mass spectrometry (UHPLC-MS/MS) led to the identification of 18 metabolites of ABZ formed in the ribwort. In both model systems, the same types of ABZ biotransformation reactions were found, but the spectrum and abundance of the ABZ metabolites detected in cell suspensions and regenerants differed significantly. Cell suspensions seem to be suitable only for qualitative estimations of drug biotransformation reactions while regenerants were shown to represent an adequate model for the qualitative as well as quantitative evaluation of drug uptake and metabolism in plants. Copyright © 2017. Published by Elsevier Inc.

Study on large release frequency of nuclear power plants

International Nuclear Information System (INIS)

Chen Yan; Song Wei; Li Chaojun; Fu Zhiwei; Wang Zhe; Zuo Jiaxu; Tong Jiejuan

2014-01-01

There are several definitions of large release frequency of nuclear power plant. This paper reviews the meanings of large release and requirement of large release frequency provided by IAEA, NRC and WENRA, analyses the relationship between the meanings of large release, compares the calculations of several large release frequencies, It is different frequency that the definition of LRF is not same. Last we discuss the difference between large release frequency and large early release frequency and explore the suitable definitions of LRF for nuclear power plants in China. (authors)

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.

Evaluation of somatic embryogenesis and plant regeneration in ...

African Journals Online (AJOL)

In an attempt to develop a successfully reproducible in vitro regeneration protocol for a group of diverse sorghum genotypes, 10 sorghum lines including locally adapted and commercially important elite genotypes were assessed for their regeneration potential on different culture media–containing adequate growth ...

Low-frequency pulsed electromagnetic field pretreated bone marrow-derived mesenchymal stem cells promote the regeneration of crush-injured rat mental nerve.

Science.gov (United States)

Seo, NaRi; Lee, Sung-Ho; Ju, Kyung Won; Woo, JaeMan; Kim, BongJu; Kim, SoungMin; Jahng, Jeong Won; Lee, Jong-Ho

2018-01-01

Bone marrow-derived mesenchymal stem cells (BMSCs) have been shown to promote the regeneration of injured peripheral nerves. Pulsed electromagnetic field (PEMF) reportedly promotes the proliferation and neuronal differentiation of BMSCs. Low-frequency PEMF can induce the neuronal differentiation of BMSCs in the absence of nerve growth factors. This study was designed to investigate the effects of low-frequency PEMF pretreatment on the proliferation and function of BMSCs and the effects of low-frequency PEMF pre-treated BMSCs on the regeneration of injured peripheral nerve using in vitro and in vivo experiments. In in vitro experiments, quantitative DNA analysis was performed to determine the proliferation of BMSCs, and reverse transcription-polymerase chain reaction was performed to detect S100 (Schwann cell marker), glial fibrillary acidic protein (astrocyte marker), and brain-derived neurotrophic factor and nerve growth factor (neurotrophic factors) mRNA expression. In the in vivo experiments, rat models of crush-injured mental nerve established using clamp method were randomly injected with low-frequency PEMF pretreated BMSCs, unpretreated BMSCs or PBS at the injury site (1 × 10 6 cells). DiI-labeled BMSCs injected at the injury site were counted under the fluorescence microscope to determine cell survival. One or two weeks after cell injection, functional recovery of the injured nerve was assessed using the sensory test with von Frey filaments. Two weeks after cell injection, axonal regeneration was evaluated using histomorphometric analysis and retrograde labeling of trigeminal ganglion neurons. In vitro experiment results revealed that low-frequency PEMF pretreated BMSCs proliferated faster and had greater mRNA expression of growth factors than unpretreated BMSCs. In vivo experiment results revealed that compared with injection of unpretreated BMSCs, injection of low-frequency PEMF pretreated BMSCs led to higher myelinated axon count and axon density and

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.

Regeneration of Algerian germplasm by stigma/style somatic ...

African Journals Online (AJOL)

... days in most of the cultured genotypes. Formed embryos were cultured in a single tube before in vivo acclimatization. After sanitary assays, regenerated plants were shown to be free from the agents detected in the mother trees. Key words: Algeria, citrus germplasm, plant regeneration, sanitation, somatic embryogenesis.

Effect of Plant Growth Regulators on Callogenesis and Regeneration Of Fritillaria imperialis L

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Esmaeil Chamani

2018-02-01

Full Text Available Introduction: Crown imperial (Fritillariaimperialis L. is an ornamental and medicinal plant native to mountainous regions of Iran. This plant genetic resources is in danger of extinction, because of grazing livestock and pest outbreaks. However, due to slow reproduction in natural conditions and traditional multiplication methods such as scaling and Bulb division, many species of this genus are endangered. Using of biotechnology, namely in vitro plant propagation, is a solution to the problems of reproduction of rare and endangered plant species with difficult propagation and mass production of valuable genotypes. Therefore, micropropagation of F. imperialis through in vitro regeneration is essential for conservation and commercial production. Material and Methods: The bulbs of F. imperialis in dormancy stage obtained from Ilam mountainous regions in Iran and theywere placed in wet vermiculite at 4 °C for 4-6 weeks. Then, Bulbs were surface-sterilized with 70% ethanol for 60s followed by immersion in 5% (v/v NaOCl solution for 20min with gentle agitation, and they rinsed three times in sterile double distilled water. Explants prepared from the lower third of scales with basal plate and were placed in MS basal medium supplemented with different concentrations of NAA and 2,4-D for callus induction. Test tubes with bulb segments were maintained within 25±2°C in growth chamber at 16 hours light period by the illumination from white florescent tube light and 8 hours dark. After two months callus were transferred to MS basal medium without PGRs. Then, callus excised to 0.5 cm pieces and were transferred to MS basal medium supplemented with NAA in 0, 0.3 and 1 mg/l concentration.Three types of cytokinins with different concentrations were arranged in three seperated experiments. Thefirst experiment medium contained NAA with BA (0, 0.3, 0.5 and 1 mg/l, the second experiment NAA combined with 0, 0.1, 0.3 and 0.5 mg/l TDZ and the third experiment MS

Coincident effect characteristic in a thermoacoustic regenerator

International Nuclear Information System (INIS)

Liu Yicai; Xin Tianlong; Huang Qian; Shi Xiangnan; Chen Siming; Chen Lixin

2011-01-01

Many previous studies on characteristics of thermoacoustic regenerator are based on fluid micro-groups and their compression-expansion cycle. In this paper, coincident frequency is introduced to evaluate its acoustic characteristics by combining structural acoustic with structural vibration theories. The relationship among structure wave radiation and regenerator position, slab thickness, and properties of material are analyzed by numerical calculation. The results show that in the low-frequency thermoacoustic system, the coincident effect generated by higher frequency wave weakens the fundamental sound wave. While in the high-frequency thermoacoustic system, where the oscillating fundamental frequency is higher than the coincident frequency, the sound field strength is enhanced by stronger structure wave radiation because of the coincident effect.

The effect of plant growth regulators on optimization of tissue culture ...

African Journals Online (AJOL)

Mature seeds of four upland rice cultivars namely Kusan, Lamsan, Selasi and Siam were assessed for callus induction and plant regeneration on different concentrations and combinations of plant growth regulators, incorporated into MS (Murashige and Skoog) basal medium. Callus induction frequency was significantly ...

Genotype, explant, medium, light and radiation effects on the in vitro plant regeneration in alfalfa (Medicago Sativa L.)

International Nuclear Information System (INIS)

El-Fiki, A.A.; Abdel-Hameed, A.A.M.; Sayed, A.I.H.

2005-01-01

The relative importance of genotype, explants, radiation, medium and light and their interactions for in vitro plant regeneration via somatic embryogenesis in alfalfa (Medicago sativa L.) has been studied. Shoot and leaf explants of two commercially grown Egyptian cultivars, Al-Wadi Al-Gadid and Siwa Tarkibi, were used in the study. The effect of gamma radiation doses 40, 80, 120 and 160 Gy were negative on plant regeneration, in spite of increase with some treatments. The best results of plant regeneration were obtained with dose 40 Gy with control light regime (16 h) on MS + 0.5 mg NAA + 1.5 mg BAP in both shoot and leaf explants of cv. Al-Wadi. The shoot explant of cv. Siwa was sensitive for gamma radiation dose 40 Gy while affirmative effect was obtained in leaf explant on MS + 1.0 mg NAA + 0.5 mg BAP with control light regime. However, dose 80 Gy showed the best results on MS + 0.5 mg NAA + 0.5 mg BAP in shoot and leaf explants of both cultivars, with control light regime in shoot explant and dark/light (DL) and dark/dark (DD) in leaf explant of cv. Al-Wadi, while with light/dark (LD) in shoot explant and control light regime in leaf explant of cv. Siwa. On the other hand, the highest plant regeneration ratio observed with dose 120 Gy were on 1.5 mg NAA + 0.5 mg BAP with control light regime in shoot and leaf explants of cv. Al-Wadi but on 0.5 mg NAA + 0.5 mg BAP with control and dark/light (DL) light regime in shoot and leaf explants of cv. Siwa. Whereas, the radiation dose 160 Gy showed severe effect on plant regeneration in both cultivars but highest percentage was observed on MS + 0.5 mg NAA + 0.5 mg BAP with dark/light (DL) in shoot explant, MS + 0.5 mg NAA + 1.5 mg BAP with control light regime in leaf explant of cv. Al-Wadi, MS + 0.5 mg NAA + 1.5 mg BAP in shoot explant and MS + 0.5 mg NAA + 0.5 mg BAP in leaf explant with dark/light (DL) in cv. Siwa. However, the effects of the same doses on callus growth showed that the highest callus weight was

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

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

An efficient in vitro shoot regeneration from leaf petiolar explants and ex vitro rooting of Bixa orellana L.- A dye yielding plant.

Science.gov (United States)

Mohammed, Arifullah; Chiruvella, Kishore K; Namsa, Nima D; Ghanta, Rama Gopal

2015-07-01

Bixa orellana L. (Bixaceae) is a multipurpose tree grown for the production of commercially important dyes. In the present study, an efficient, reproducible protocol was developed for direct plant regeneration from in vitro derived petiole explants of Bixa orellana L. Murashige and Skoog medium (MS) supplemented with 2-isopentenyl adenine (9.8 μM) and naphthalene acetic acid (10.7 μM) was found to be optimum for production of high frequency of shoot organogenesis. Subculturing of the shoots onto the fresh MS medium containing similar concentrations of 2-iP (9.8 μM) and NAA (10.7 μM) produced elongated shoots. Elongated shoots when placed onto MS medium supplemented with 1.7 μM indole-3-acetic acid and 14.7 μM 2-iP produced optimal rooting. Rooted plantlets were acclimatized and transplanted to the field successfully. Histological investigation revealed the origin of shoot primordia, from sub-epidermal cells of petiole explants. The regeneration protocol developed in this study can be useful for mass in vitro propagation and effective genetic transformation of commercially important edible dye yielding tree species.

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

African Journals Online (AJOL)

UKZN

2012-10-18

Oct 18, 2012 ... explants produced highly recalcitrant callus that did not regenerate into ... Key words: Tissue culture, regeneration, sweet potato, genetic transformation. .... sterilized in 5% (v/v) sodium hypochlorite solution for 20 min and.

Bottlenecks in the generation and maintenance of morphogenic banana cell suspensions and plant regeneration via somatic embryogenesis therefrom

Czech Academy of Sciences Publication Activity Database

Schoofs, H.; Panis, B.; Strosse, H.; Mosqueda, A. M.; Torres, J. L.; Roux, N.; Doležel, Jaroslav; Swennen, R.

2001-01-01

Roč. 8, č. 2 (2001), s. 3-7 ISSN 0989-8972 R&D Projects: GA MŠk ME 376 Institutional research plan: CEZ:AV0Z5038910 Keywords : banana cell suspensions * plant regeneration Subject RIV: EA - Cell Biology

Enhancement of organ regeneration in animal models by a stem cell-stimulating plant mixture.

Science.gov (United States)

Kiss, István; Tibold, Antal; Halmosi, Róbert; Bartha, Eva; Koltai, Katalin; Orsós, Zsuzsanna; Bujdosó, László; Ember, István

2010-06-01

Adult stem cells play an important role in the regeneration of damaged organs. Attempts have already been made to enhance stem cell production by cytokines, in order to increase the improvement of cardiac functions after myocardial infarction. In our present study we investigated the possibility whether instead of cytokine injection dietary stimulation of stem cell production accelerates the organ regeneration in animals. A dietary supplement, Olimpiq StemXCell (Crystal Institute Ltd., Eger, Hungary), containing plant extracts (previously proved to increase the number of circulating CD34(+) cells) was consumed in human equivalent doses by the experimental animals. In the first experiment carbon tetrachloride was applied to CBA/Ca mice, to induce liver damage, and liver weights between StemXCell-fed and control animals were compared 10 days after the treatment. In the second model experimental diabetes was induced in F344 rats by alloxan. Blood sugar levels were measured for 5 weeks in the control and StemXCell-fed groups. The third part of the study investigated the effect of StemXCell on cardiac functions. Eight weeks after causing a myocardial infarction in Wistar rats by isoproterenol, left ventricular ejection fraction was determined as a functional parameter of myocardial regeneration. In all three animal models StemXCell consumption statistically significantly improved the organ regeneration (relative liver weights, 4.78 +/-0.06 g/100 g vs. 4.97 +/- 0.07 g/100 g; blood sugar levels at week 5, 16 +/- 1.30 mmol/L vs. 10.2 +/- 0.92 mmol/L; ejection fraction, 57.5 +/- 2.23 vs. 68.2 +/- 4.94; controls vs. treated animals, respectively). Our study confirms the hypothesis that dietary enhancement of stem cell production may protect against organ injuries and helps in the regeneration.

Localization of QTLs for in vitro plant regeneration in tomato.

Science.gov (United States)

Trujillo-Moya, Carlos; Gisbert, Carmina; Vilanova, Santiago; Nuez, Fernando

2011-10-20

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. 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 to regeneration. In this study we have

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

Reproducible and expedient rice regeneration system using in vitro ...

African Journals Online (AJOL)

Inevitable prerequisite for expedient regeneration in rice is the selection of totipotent explant and developing an apposite combination of growth hormones. Here, we reported a reproducible regeneration protocol in which basal segments of the stem of the in vitro grown rice plants were used as ex-plant. Using the protocol ...

Regeneration of Sudanese maize inbred lines and open pollinated ...

African Journals Online (AJOL)

STORAGESEVER

2008-06-03

Jun 3, 2008 ... Callus induction capacity was highest in inbred lines IL3, IL15 and IL1. The. Varieties Hudiba-2 and ... Maize plant regeneration can take place through two avenues, that is ..... regenerants were tussel ear formation and dwarfism. These abnormalities are typical of tissue-cultured cells, plants derived from ...

Infection of Early and Young Callus Tissues of Indica Rice BPT 5204 Enhances Regeneration and Transformation Efficiency

Directory of Open Access Journals (Sweden)

P. MANIMARAN

2013-11-01

Full Text Available 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 calli showed high transformation frequency followed 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.

Effects of N6-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

2012-01-01

Different concentrations of N6-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. PMID:24575235

The regeneration of epidermal cells of Saintpaulia leaves as a new plant-tissue system for cellular radiation biology

International Nuclear Information System (INIS)

Engels, F.M.; Laan, F.M. van der; Leenhouts, H.P.; Chadwick, K.H.

1980-01-01

investigation of the nucleus of epidermal cells of the petioles of Saintpaulia leaves by cytofluorimetry revealed that all cells are in a non-cycling pre DNA synthesis phase. Cultivation of dissected leaves results in a synchronous regeneration process of a defined number of cells. Five days after onset of cultivation the cells reach the first mitosis. The nuclear development during the regeneration process is described. Irradiation of the leaves results in a directly visible inhibition of this regenerating capability which is used to quantify cell survival in a tissue. The data show that the radiation response has a similar shape to that of the survival of single cells in culture. This response can be observed before the first mitosis of the cells and its application as a new plant tissue system for cellular radiation research is discussed. (author)

Direct regeneration and efficient in vitro root development studies in lentil (lens culinaris medik)

International Nuclear Information System (INIS)

Sultana, T.; Majeed, N.; Naqvi, S.

2016-01-01

Lentil is a self-pollinating annual crop with increasing demand all over the world due to its high protein content and easy digestibility. However, like many other crops lentil too needs improvement for which conventional as well as biotechnological tools are to be employed. This study was aimed at development of tissue culture protocol especially targeting improved root development to ensure their establishment in soil in order to use their potential towards genetic manipulation. Two Pakistani lentil cultivars, Masoor-2002 and Manshera-89 were used to obtain cotyledonary nodes, epicotyl and hypocotyl explants. The explants were cultured on shoot regeneration medium containing different concentration of kinetin, BAP and tyrosine with the addition of GA3, with or without charcoal for shoot development. Masoor-2002, showed the highest frequency of shoot development on MS medium containing 5.5 mg/L tyrosine, 0.25 mg/L kinetin, 1.0 mg/L BAP, 0.1 mg/L GA3, using cotyledonary node as explant. The addition of 2 g/L of charcoal in shoot medium resulted in healthier plants, but the number of shoots were reduced. Regarding the effect of age of explants on regeneration frequency, cotyledonary nodes of age 4-6 days had higher regeneration potential. Well-developed shoots were shifted to rooting medium containing different concentration of auxin with or without charcoal. Healthier and more roots were observed on medium containing 4 mg/L IAA with addition of 2 g/L charcoal. Plants were better established (70% survival) in a soil mix containing perlite, vermiculite and peat moss in 1:1:1 ratio. (author)

Recloning of regenerated plantlets from elite oil palm ( Elaeis ...

African Journals Online (AJOL)

Plant regeneration in oil palm cv. Tenera via somatic embryogenesis was conducted using regenerated plantlets as an explant source. Explants from different positions – apex, middle and basal segments of regenerated plantlets – were cultured in N6 medium supplemented with 100, 120 and 140 mg/L 2 ...

The influence of the solid thermal conductivity on active magnetic regenerators

DEFF Research Database (Denmark)

Nielsen, Kaspar Kirstein; Engelbrecht, Kurt

2012-01-01

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...... 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...... 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...

Nucleated regeneration of semiarid sclerophyllous forests close to remnant vegetation

NARCIS (Netherlands)

Fuentes-Castillo, T.; Miranda, A.; Rivera-Hutinel, A.; Smith-Ramirez, C.; Holmgren, M.

2012-01-01

Natural regeneration of mediterranean plant communities has proved difficult in all continents. In this paper we assess whether regeneration of sclerophyllous forests shows nucleated patterns indicative of a positive effect of vegetation remnants at the landscape level and compare the regeneration

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.

In vitro regeneration of selected commercial Tanzanian open ...

African Journals Online (AJOL)

Using this regeneration system Situka M-1, Staha and TMV-1 can now be improved against various production constraints through genetic engineering. Key words: 2, 4-dichlorophexyacetic acid, embryogenic callus, immature zygotic embryos, regeneration frequency, somatic embryos, Tanzanian open pollinated maize.

Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

Directory of Open Access Journals (Sweden)

Rizwan RASHID

2010-03-01

Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., �Punjab Upma� and �IPA-3� for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in �Punjab Upma� and �IPA-3� per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of �Punjab Upma� and (2.93 in case of �IPA-3�. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and � MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

Effect of Hormones on Direct Shoot Regeneration in Hypocotyl Explants of Tomato

Directory of Open Access Journals (Sweden)

Rizwan RASHID

2010-03-01

Full Text Available This study was conducted for developing a high frequency regeneration system in two genotypes of tomato (Lycopersicon esculentum Mill., Punjab Upma and IPA-3 for direct shoot regeneration from hypocotyl explants. The explants were excised from in vitro tomato seedlings and cultured on MS medium supplemented with different concentrations and combinations of hormones. Direct regeneration was significantly influenced by the genotype hormones combination and concentrations. The MS medium supplemented with (Kinetin 0.5 mg/l and (BAP 0.5 mg/l was found optimum for inducing direct shoot regeneration and number of shoots per explant from hypocotyl explants on this medium. Shoot regeneration per cent in Punjab Upma and IPA-3 per cent was recorded to be highest i.e (86.02 and (82.57 respectively. Besides this, average number shoots per explant was also highest i.e (3.16 in case of Punjab Upma and (2.93 in case of IPA-3. A significant decline was observed in percent shoot regeneration and average number of shoots per explant with increase in the hormonal concentration. Shoots were obtained and transferred to the elongation medium (MS + BAP 0.3 mg/l. Hundred per cent rooting was induced in separated shoots upon culturing on MS and MS basal media. Hardening on moist cotton showed maximum plantlet survival rate in case of both genotypes. After hardening, plants were transferred to soil. Thus, a tissue culture base line was established in tomato for obtaining direct regeneration using hypocotyl as explants.

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.

Callus regeneration from stem explants of Pseudarthira viscida (L ...

African Journals Online (AJOL)

STORAGESEVER

2009-09-01

Sep 1, 2009 ... regeneration frequency have come from tissue culture work done in ... Table 1. In vitro responses from stem callus of Psudarthria viscida Wight & Arn. Growth .... plantlets regeneration from cotyledonary callus of Tomato.

Plant diversity and regeneration in a disturbed isolated dry Afromontane forest in northern Ethiopia

DEFF Research Database (Denmark)

Aynekulu, Ermias; Aerts, Raf; Denich, Manfred

2016-01-01

We studied the diversity, community composition and natural regeneration of woody species in an isolated but relatively large (> 1,000 ha) dry Afromontane forest in northern Ethiopia to assess its importance for regional forest biodiversity conservation. The principal human-induced disturbance...... in biodiversity through local extinction of indigenous tree species. Despite the problems associated with conserving plant species diversity in small and isolated populations, this relic forest is of particular importance for regional conservation of forest biodiversity, as species with high conservation value...

C4 photosynthesis in Euphorbia degeneri and E. remyi: a comparison of photosynthetic carbon metabolism in leaves, callus cultures and regenerated plants

International Nuclear Information System (INIS)

Ruzin, S.E.

1984-04-01

Based on analysis of 14 CO 2 fixation kinetics and assays of enzymes related to C 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 2 to bundle sheath cells. Callus grown on either non-shoot-forming or shoot-forming media fixes CO 2 into RPP-cycle intermediates and sucrose, as well as malate and aspartate. 14 CO 2 pulse/chase kinetics show no significant loss of label from C 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 4 photosynthesis does not occur in callus derived from this C 4 dicot but is regenerated concomitant with shoot regeneration, and β-carboxylation of PEP in callus, mediated by the low K/sub m/ isoenzyme of PEPCase, produces C 4 acids that are not involved in the CO 2 shuttle mechanism characteristic of C 4 photosynthesis. 161 references, 19 figures, 12 tables

Growing Arabidopsis in vitro: cell suspensions, in vitro culture, and regeneration.

Science.gov (United States)

Barkla, Bronwyn J; Vera-Estrella, Rosario; Pantoja, Omar

2014-01-01

An understanding of basic methods in Arabidopsis tissue culture is beneficial for any laboratory working on this model plant. Tissue culture refers to the aseptic growth of cells, organs, or plants in a controlled environment, in which physical, nutrient, and hormonal conditions can all be easily manipulated and monitored. The methodology facilitates the production of a large number of plants that are genetically identical over a relatively short growth period. Techniques, including callus production, cell suspension cultures, and plant regeneration, are all indispensable tools for the study of cellular biochemical and molecular processes. Plant regeneration is a key technology for successful stable plant transformation, while cell suspension cultures can be exploited for metabolite profiling and mining. In this chapter we report methods for the successful and highly efficient in vitro regeneration of plants and production of stable cell suspension lines from leaf explants of both Arabidopsis thaliana and Arabidopsis halleri.

Lineage tracing of genome-edited alleles reveals high fidelity axolotl limb regeneration.

Science.gov (United States)

Flowers, Grant Parker; Sanor, Lucas D; Crews, Craig M

2017-09-16

Salamanders are unparalleled among tetrapods in their ability to regenerate many structures, including entire limbs, and the study of this ability may provide insights into human regenerative therapies. The complex structure of the limb poses challenges to the investigation of the cellular and molecular basis of its regeneration. Using CRISPR/Cas, we genetically labelled unique cell lineages within the developing axolotl embryo and tracked the frequency of each lineage within amputated and fully regenerated limbs. This allowed us, for the first time, to assess the contributions of multiple low frequency cell lineages to the regenerating limb at once. Our comparisons reveal that regenerated limbs are high fidelity replicas of the originals even after repeated amputations.

Plant Regeneration and Cellular Behaviour Studies in Celosia cristata Grown In Vivo and In Vitro

Science.gov (United States)

Taha, Rosna Mat; Wafa, Sharifah Nurashikin

2012-01-01

Tissue culture studies of Celosia cristata were established from various explants and the effects of various hormones on morphogenesis of this species were examined. It was found that complete plant regeneration occurred at highest percentage on MS medium supplemented with 2.0 mg/L NAA and 1.5 mg/L BAP, with the best response showed by shoot explants. In vitro flowering was observed on MS basal medium after six weeks. The occurrence of somaclonal variation and changes in cellular behavior from in vivo and in vitro grown plants were investigated through cytological studies and image analysis. It was observed that Mitotic Index (MI), mean chromosome numbers, and mean nuclear to cell area ratio of in vitro root meristem cells were slightly higher compared to in vivo values. However, in vitro plants produced lower mean cell areas but higher nuclear areas when compared to in vivo plants. Thus, no occurrence of somaclonal variation was detected, and this was supported by morphological features of the in vitro plants. PMID:22593677

Modeling water and hydrogen networks with partitioning regeneration units

Directory of Open Access Journals (Sweden)

W.M. Shehata

2015-03-01

Full Text Available Strict environment regulations in chemical and refinery industries lead to minimize resource consumption by designing utility networks within industrial process plants. The present study proposed a superstructure based optimization model for the synthesis of water and hydrogen networks with partitioning regenerators without mixing the regenerated sources. This method determines the number of partitioning regenerators needed for the regeneration of the sources. The number of the regenerators is based on the number of sources required to be treated for recovery. Each source is regenerated in an individual partitioning regenerator. Multiple regeneration systems can be employed to achieve minimum flowrate and costs. The formulation is linear in the regenerator balance equations. The optimized model is applied for two systems, partitioning regeneration systems of the fixed outlet impurity concentration and partitioning regeneration systems of the fixed impurity load removal ratio (RR for water and hydrogen networks. Several case studies from the literature are solved to illustrate the ease and applicability of the proposed method.

Regenerant arabidopsis lineages display a distinct genome-wide spectrum of mutations conferring variant phenotypes

KAUST Repository

Jiang, Caifu

2011-07-28

Multicellular organisms can be regenerated from totipotent differentiated somatic cell or nuclear founders [1-3]. Organisms regenerated from clonally related isogenic founders might a priori have been expected to be phenotypically invariant. However, clonal regenerant animals display variant phenotypes caused by defective epigenetic reprogramming of gene expression [2], and clonal regenerant plants exhibit poorly understood heritable phenotypic ("somaclonal") variation [4-7]. Here we show that somaclonal variation in regenerant Arabidopsis lineages is associated with genome-wide elevation in DNA sequence mutation rate. We also show that regenerant mutations comprise a distinctive molecular spectrum of base substitutions, insertions, and deletions that probably results from decreased DNA repair fidelity. Finally, we show that while regenerant base substitutions are a likely major genetic cause of the somaclonal variation of regenerant Arabidopsis lineages, transposon movement is unlikely to contribute substantially to that variation. We conclude that the phenotypic variation of regenerant plants, unlike that of regenerant animals, is substantially due to DNA sequence mutation. 2011 Elsevier Ltd. All rights reserved.

Regenerant arabidopsis lineages display a distinct genome-wide spectrum of mutations conferring variant phenotypes

KAUST Repository

Jiang, Caifu; Mithani, Aziz; Gan, Xiangchao; Belfield, Eric J.; Klingler, John  P.; Zhu, Jian-Kang; Ragoussis, Jiannis; Mott, Richard; Harberd, Nicholas  P.

2011-01-01

Multicellular organisms can be regenerated from totipotent differentiated somatic cell or nuclear founders [1-3]. Organisms regenerated from clonally related isogenic founders might a priori have been expected to be phenotypically invariant. However, clonal regenerant animals display variant phenotypes caused by defective epigenetic reprogramming of gene expression [2], and clonal regenerant plants exhibit poorly understood heritable phenotypic ("somaclonal") variation [4-7]. Here we show that somaclonal variation in regenerant Arabidopsis lineages is associated with genome-wide elevation in DNA sequence mutation rate. We also show that regenerant mutations comprise a distinctive molecular spectrum of base substitutions, insertions, and deletions that probably results from decreased DNA repair fidelity. Finally, we show that while regenerant base substitutions are a likely major genetic cause of the somaclonal variation of regenerant Arabidopsis lineages, transposon movement is unlikely to contribute substantially to that variation. We conclude that the phenotypic variation of regenerant plants, unlike that of regenerant animals, is substantially due to DNA sequence mutation. 2011 Elsevier Ltd. All rights reserved.

Plants experiencing chronic internal exposure to ionizing radiation exhibit higher frequency of homologous recombination than acutely irradiated plants

Energy Technology Data Exchange (ETDEWEB)

Kovalchuk, O.; Kovalchuk, I.; Hohn, B. [Friedrich Miescher Institute, P.O. Box 2543, CH-4002 Basel (Switzerland); Arkhipov, A. [Chernobyl Scientific and Technical Center of International Research, Shkolnaya Str. 6, 255620 Chernobyl (Ukraine); Barylyak, I.; Karachov, I. [Ukrainian Scientific Genetics Center, Popudrenko Str. 50, 253660 Kiev (Ukraine); Titov, V. [Ivano-Frankivsk State Medical Academy, Galitska Str.2, 284000 Ivano-Frankivsk (Ukraine)

2000-04-03

Ionizing radiation (IR) is a known mutagen responsible for causing DNA strand breaks in all living organisms. Strand breaks thus created can be repaired by different mechanisms, including homologous recombination (HR), one of the key mechanisms maintaining genome stability [A. Britt, DNA damage and repair in plants, Annu. Rev. Plant. Phys. Plant Mol. Biol., 45 (1996) 75-100; H. Puchta, B. Hohn, From centiMorgans to basepairs: homologous recombination in plants, Trends Plant Sci., 1 (1996) 340-348.]. Acute or chronic exposure to IR may have different influences on the genome integrity. Although in a radioactively contaminated environment plants are mostly exposed to chronic pollution, evaluation of both kinds of influences is important. Estimation of the frequency of HR in the exposed plants may serve as an indication of genome stability. We used previously generated Arabidopsis thaliana and Nicotiana tabacum plants, transgenic for non-active versions of the {beta}-glucoronidase gene (uidA) [P. Swoboda, S. Gal, B. Hohn, H. Puchta, Intrachromosomal homologous recombination in whole plants, EMBO J., 13 (1994) 484-489; H. Puchta, P. Swoboda, B. Hohn, Induction of homologous DNA recombination in whole plants, Plant, 7 (1995) 203-210.] serving as a recombination substrate, to study the influence of acute and chronic exposure to IR on the level of HR as example of genome stability in plants. Exposure of seeds and seedlings to 0.1 to 10.0 Gy 60Co resulted in increased HR frequency, although the effect was more pronounced in seedlings. For the study of the influence of chronic exposure to IR, plants were grown on two chemically different types of soils, each artificially contaminated with equal amounts of 137Cs. We observed a strong and significant correlation between the frequency of HR in plants, the radioactivity of the soil samples and the doses of radiation absorbed by plants (in all cases r0.9, n=6, P<0.05). In addition, we noted that plants grown in soils with

Research Note Effects of previous cultivation on regeneration of ...

African Journals Online (AJOL)

We investigated the effects of previous cultivation on regeneration potential under miombo woodlands in a resettlement area, a spatial product of Zimbabwe's land reforms. We predicted that cultivation would affect population structure, regeneration, recruitment and potential grazing capacity of rangelands. Plant attributes ...

Somatic embryogenesis from seeds in a broad range of Vitis vinifera L. varieties: rescue of true-to-type virus-free plants.

Science.gov (United States)

San Pedro, Tània; Gammoudi, Najet; Peiró, Rosa; Olmos, Antonio; Gisbert, Carmina

2017-11-29

Somatic embryogenesis is the preferred method for cell to plant regeneration in Vitis vinifera L. However, low frequencies of plant embryo conversion are commonly found. In a previous work we obtained from cut-seeds of a grapevine infected with the Grapevine leafroll associated viruses 1 and 3 (GLRaV-1 and GLRaV-3), high rates of direct regeneration, embryo plant conversion and sanitation. The aim of this study is to evaluate the usefulness of this procedure for regeneration of other grapevine varieties which include some infected with one to three common grapevine viruses (GLRaV-3, Grapevine fanleaf virus (GFLV) and Grapevine fleck virus (GFkV)). As grapevine is highly heterozygous, it was necessary to select from among the virus-free plants those that regenerated from mother tissues around the embryo, (true-to-type). Somatic embryogenesis and plant regeneration were achieved in a first experiment, using cut-seeds from the 14 grapevine varieties Airén, Cabernet Franc, Cabernet Sauvignon, Mencía, Merlot, Monastrell, Petit Verdot, Pinot Blanc (infected by GFLV and GFkV), Pinot Gris, Pinot Meunier, Pinot Noir, Syrah, Tempranillo (infected by GFLV), and Verdil. All regenerated plants were confirmed to be free of GFkV whereas at least 68% sanitation was obtained for GFLV. The SSR profiles of the virus-free plants showed, in both varieties, around 10% regeneration from mother tissue (the same genetic make-up as the mother plant). In a second experiment, this procedure was used to sanitize the varieties Cabernet Franc, Godello, Merlot and Valencí Blanc infected by GLRaV-3, GFkV and/or GFLV. Cut-seeds can be used as explants for embryogenesis induction and plant conversion in a broad range of grapevine varieties. The high regeneration rates obtained with this procedure facilitate the posterior selection of true-to-type virus-free plants. A sanitation rate of 100% was obtained for GFkV as this virus is not seed-transmitted. However, the presence of GLRaV-3 and GFLV in

Economic analysis of replacement regeneration and coppice regeneration in eucalyptus stands under risk conditions

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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.

In vitro regeneration of selected commercial Tanzanian open ...

African Journals Online (AJOL)

Yomi

2012-03-15

Mar 15, 2012 ... regenerated in vitro using immature zygotic embryos as ex-plants. Callus induction .... Ears were harvested between 12 to 16 days post pollination depending on .... After 28 days of culture on CMM, a mass of dedifferentiated cells .... showed high regeneration ability compared to Situka M-1 that had good ...

Differential responses to isoprenoid, N-6-substituted aromatic cytokinins and indole-3-butyric acid in direct plant regeneration of Eriocephalus africanus

Czech Academy of Sciences Publication Activity Database

Madzikane-Mlungwana, O.; Moyo, M.; Aremu, A.O.; Plíhalová, Lucie; Doležal, Karel; Van Staden, J.; Finnie, J.F.

2017-01-01

Roč. 82, č. 1 (2017), s. 103-110 ISSN 0167-6903 R&D Projects: GA MŠk(CZ) LO1204 Institutional support: RVO:61389030 Keywords : in-vitro cultures * auxin transport * meta-topolin * antioxidant activity * biological-activity * arabidopsis roots * phenolic-acids * l. asteraceae * south-africa * flavonoids * Auxins * Cytokinins * Flavonoids * Plant regeneration * Phenolics Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Plant sciences, botany Impact factor: 2.646, year: 2016

The effects of gamma-ray irradiation to strawberry (Fragaria x ananassa Duch.) calli on shoot regeneration, achene formation and morphological variations of regenerants

International Nuclear Information System (INIS)

Kasumi, Masakazu

2002-01-01

Strawberry (Fragaria x ananassa 'Nyoho') calli, derived from anthers, were irradiated with gamma -ray at dosages from 100 to 1,600 Gy (10 Gy · hr - 1) and their effects on callus growth, plant regeneration, and somaclonal variation were analyzed. The growth of callus and percentage of plant regeneration from the callus were reduced slightly at dosages less than 200 Gy, moderately at 400 Gy, and markedly above 800 Gy. Fruit growth associated with seed fertility (>50 % ) was morphologically normal at less than 100 Gy, whereas achene formation was significantly inhibited above 200 Gy. The percentages of morphological variation in regenerants formed from the irradiated callus were:13.7 (no irradiation), 18.6 (100 Gy), 66.0 (200 Gy), 75.7 (400 Gy), and 97.0 (800 Gy). Furthermore, higher dosages yielded wider variations, e.g., thick and small leaf, light leaf color, white flesh, and long fruit. In some regenerants, more than one morphological aberrations developed, some of which were transmissible to daughter plants. These results revealed that the irradiating strawberry callus with gamma - ray resulted in a higher degree and wider spectrum of somaclonal variation than did simple callus culture. (author)

CALCULATED REGENERATOR PERFORMANCE AT 4 K WITH HELIUM-4 AND HELIUM-3

International Nuclear Information System (INIS)

Radebaugh, Ray; Huang Yonghua; O'Gallagher, Agnes; Gary, John

2008-01-01

The helium-4 working fluid in regenerative cryocoolers operating with the cold end near 4 K deviates considerably from an ideal gas. As a result, losses in the regenerator, given by the time-averaged enthalpy flux, are increased and are strong functions of the operating pressure and temperature. Helium-3, with its lower boiling point, behaves somewhat closer to an ideal gas in this low temperature range and can reduce the losses in 4 K regenerators. An analytical model is used to find the fluid properties that strongly influence the regenerator losses as well as the gross refrigeration power. The thermodynamic and transport properties of helium-3 were incorporated into the latest NIST regenerator numerical model, known as REGEN3.3, which was used to model regenerator performance with either helium-4 or helium-3. With this model we show how the use of helium-3 in place of helium-4 can improve the performance of 4 K regenerative cryocoolers. The effects of operating pressure, warm-end temperature, and frequency on regenerators with helium-4 and helium-3 are investigated and compared. The results are used to find optimum operating conditions. The frequency range investigated varies from 1 Hz to 30 Hz, with particular emphasis on higher frequencies

Post-fire regeneration of vegetation on sandy oligotrophic soil, in Itabaiana, Sergipe, Brazil

Directory of Open Access Journals (Sweden)

Túlio Vinicius Paes Dantas

2015-07-01

Full Text Available Two models of post-disturbance regeneration of vegetation in areas of oligotrophic soils have been proposed for temperate regions. The first model is characterized by rapid recovery of the floristic composition, due to the fire resistance of plants; while in the second model, the fire causes extensive mortality and the recovery occurs by recruitment from the seed bank. Since these models have been rarely tested in tropical oligotrophic environments, we applied them in the analysis of floristic compositions in three areas with different post-fire regeneration times in Sergipe State, Brazil. The regeneration followed the seed bank recruitment model in places of bare ground, with a progressive increase in plant density and changes in the relative abundance and dominance of the populations along the successional process. The parameters that best allowed the succession evaluation were the floral similarity, plant height and density, which increased as regeneration progressed. The stem diameter and tillering were inconclusive as parameters for assessing the regeneration progress.

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.

MHD (Magnetohydrodynamics) recovery and regeneration

Energy Technology Data Exchange (ETDEWEB)

McIlroy, R. A. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Probert, P. B. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Lahoda, E. J. [Westinghouse Electric Corp., Pittsburgh, PA (United States); Swift, W. M. [Argonne National Lab. (ANL), Argonne, IL (United States); Jackson, D. M. [Univ. of Tennessee Space Inst. (UTSI), Tullahoma, TN (United States); Prasad, J. [Univ. of Tennessee Space Inst. (UTSI), Tullahoma, TN (United States); Martin, J. [Hudson Engineering (United States); Rogers, C. [Hudson Engineering (United States); Ho, K. K. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Senary, M. K. [Babcock and Wilcox Co., Alliance, OH (United States). Research Center; Lee, S. [Univ. of Akron, OH (United States)

1988-10-01

A two-phase program investigating MHD seed regeneration is described. In Phase I, bench scale experiments were carried out to demonstrate the technical feasibility of a proposed Seed Regeneration Process. The Phase I data has been used for the preliminary design of a Proof-of-Concept (POC) plant which will be built and tested in Phase II. The Phase I data will also be used to estimate the costs of a 300 Mw(t) demonstration plant for comparison with other processes. The Seed Regeneration Process consists of two major subprocesses; a Westinghouse Dry Reduction process and a modified Tampella (sulfur) Recovery process. The Westinghouse process reduces the recovered spent seed (i.e., potassium sulfate) to potassium polysulfide in a rotary kiln. The reduction product is dissolved in water to form green liquor, clarified to remove residual coal ash, and sent to the Tampella sulfur release system. The sulfur is released using carbon dioxide from flue gas in a two stage reaction. The sulfur is converted to elemental sulfur as a marketable by product. The potassium is crystallized from the green liquor and dried to the anhydrous form for return to the MHD unit.

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...

Effects of Ultrasound, Tryptophan and Proline on embryogenesis and regeneration of grape (Vitis vinifera L.

Directory of Open Access Journals (Sweden)

Yousef Farokhzad

2016-10-01

Full Text Available Genetic improvement of Grape is limited by traditional methods. An effective regeneration system for tissues culture of transgenic adult plants could facilitate genetic modification of them. So it is necessary to develop and improve embryogenesis and regeneration systems in plants. Accordingly the aim of the present study was to evaluate the effects of ultrasound (0 (as control, 60, 120 and 240 second, tryptophan (0 (as control, 50,100, 200 µM and proline content (0 (as control, 50, 100 and 200 µM on grape stem internodes explants in Kodori cultivar. This project was performed in factorial experiment (two factors in the basis of completely randomized design with three replications at tissue culture laboratory of Shahed University of Tehran. Results showed that both ultrasound and two explained amino acids had significant effects on studied characteristics such as callus frequency, callus length and width, fresh weight, embryo numbers in each callus and their germination percentage. Generally, using 100 µM tryptophan and proline coincide with 120 second ultrasound had highest positive effects on the most studied characteristics.

The effect of plant growth regulators on callus induction somatic embryogenesis of hybird tomato

International Nuclear Information System (INIS)

Jan, S. A.; Shah, S. H.; Ali, S.; Ali, G. H.

2015-01-01

Efficient tissue culture system is important for transformation of important genes in hybrid tomato cultivars. The present study was undertaken to develop an efficient tissue culture system for hybrid tomato cultivar Peto-86. The young primary leaves and stems were inoculated into five different MS media having different concentrations of plant growth regulators in different combinations for callus induction, somatic embryogenesis and for both direct and indirect regeneration. Maximum callus induction frequency 90 percentage was achieved with MS media containing 2,4-D 4 mg L-1 and BAP 0.5 mg L-1. The direct somatic embryogenesis was found highest on MS media supplemented with 2,4-D 4 mg L-1 and BAP 0.5 mg L-1. Maximum indirect regeneration frequency 87 percentage was achieved from primary leaves explants with MS media containing IAA 0.5 mg L-1 and BAP 3 mg L-1 and highest direct regeneration frequency 77% was obtained from primary leaves explants with MS media containing NAA 1 mg L-1 and BAP 3 mg L-1. The high concentration of 2,4-D increased callus induction and somatic embryogenesis frequencies while the high concentration of BAP increased regeneration frequency. An improved tissue culture system of hybrid tomato cultivar Peto-86 was established and it may be recommended for further transformation experiments. (author)

CRYOTHERAPY: A NEW TECHNIQUE TO OBTAIN GRAPEVINE PLANTS FREE OF VIRUSES

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JEAN CARLOS BETTONI

2016-01-01

Full Text Available ABSTRACT Through in vitro tissue culture techniques it is possible to propagate high quality nursery plants faster. Cryotherapy is a promising tool, based on in vitro culture techniques, for achieving in a short time, high frequency of regenerating plants free of viruses. The objective of this review is to present and analyze the results of research conducted in cryotherapy methods based on cryopreservation protocols for recovery of cultivars free of micro-organisms with potential agronomic interest. The main methods employed in cryotherapy are encapsulation-dehydration, vitrification, encapsulation-vitrification and droplet vitrification, which are based on the immersion of preconditioned shoot tips in liquid nitrogen, followed by their recovery in vitro on to culture media for regeneration of healthy plantlets. Improvements to cryotherapy protocols used for grapevine are still needed, since there are variations in response according to the genotype. The published research mostly relates to Vitis vinifera and the few studies applied to other species show that the protocols need to be improved. This specificity goes beyond species, with different responses among cultivars, limiting the broader application of the technology. On the other hand, traditional methods used for virus removal from infected plant materials also have limitations and therefore investment in research for the development and application of cryopreservation techniques is highly justified, considering its efficiency and low-cost, once the protocols are developed. High frequency of virus-free plants among regenerants within a short time frame is the most desirable aspect of cryotherapy. Therefore, these advantages make the technique a promising tool for institutions mandated to the development of high-health planting materials with high genetic and agronomic potential for viticulture.

In vitro regeneration of Basella alba L

Science.gov (United States)

Edney, Norris Allen; Rizvi, Muhammad A.; Rizvi, Narjis F.

1989-01-01

Basella alba L. is a tropical vine used as a vegetable in some Asian and African countries. It has potential as a nontraditional crop for small family farms. A short day plant, it blooms during the fall, provided the temperatures are mild. In the southeastern U.S., the short days of fall are associated with subfreezing temperatures, and plants are killed before blooming. Attempts were made to regenerate the plant using tissue culture techniques. Several trials were conducted with different media, hormones, and explants. It was found that nodal segments on Gamborg medium regenerated shoots. Interaction studies of auxins and cytokinins indicated that its endogeneous auxin content might be high because callus proliferated in almost all treatments and roots initiated even when the medium was not supplemented with an auxin.

Highly efficient in vitro adventitious shoot regeneration of Adenosma ...

African Journals Online (AJOL)

Adenosma glutinosum (Linn.) Druce is an important aromatic plant, but no information is available regarding its regeneration, callus induction and proliferation from leaf explants. In this study, an in vitro shoot regeneration procedure was developed for native A. glutinosum using leaf explants. Callus induction and shoots ...

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...... culture ability in immature embryo culture i.e. Femina, Salome and Corniche. Barley spikes were emasculated and hand pollinated 3 days after emasculation. In barley, fertilization takes place one hour after pollination and ovules with fertilized egg cells could therefore be isolated one hour after...... 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...

Development of an Efficient Regeneration and Transformation Method for Nicothiana tabacum L. through the Optimization of Growth Regulators and Sucrose Concentration

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maria Beihaghi

2018-03-01

on the selective medium with different concentrations of antibiotic. For genetic transformation, agrobacterium tumifacious (GV3101 harboring plasmid pBI121 was used and the transgenic plants were confirmed by PCR analysis. Results and Discussion: The results of variance analysis and the means comparison showed that the best medium for callus induction was M1 (0.1 mg/l NAA and 1 mg/l BAP with 15 g/l sucrose in the leaf explants, while the most direct shoot regeneration rate was obtained on the M1 medium with 30 g/l sucrose concentration. High-frequency of rooting was also influenced by 0/1 mg/l NAA and 60 g/l sucrose. So, supplementing the medium with NAA and BAP at different concentrations facilitated induction of multiple shoots from explants. NAA was proved to be the best and the number of shoots increased with increase in the concentration up to (0.1 mg/l, and exceeding this concentration resulted in decline in percent response as well as number of shoots was recorded shoot regeneration. The concentration of BAP was further increased a linear increase in the number of shoots was observed up to an optimal level (1 mg/l. Beyond the optimal concentration (1 mg/l, a decrease in the response as well as number of shoots was recorded due to profuse basal callusing. The effect of cytokinins on multiple shoot regeneration, higher concentrations of NAA found to be inhibitory for shoot regeneration because of huge callusing which hampered the growth and development of new shoots. Also different concentrations of sucrose have a different effect on the shoots and callus. The concentration of sucrose had significant effect on direct shoot regeneration. The main effect of sucrose concentration, concentration of 30 grams per liter, compared with a concentration of 15 grams per liter had the highest direct shoot regeneration. Concentration of 50 mg/l kanamycin could completely prevent the regeneration of untransformed explants so was used in the selective culture medium

Reproducible in vitro regeneration system for purifying sugarcane ...

African Journals Online (AJOL)

This procedure may be considered as one of the best ever published report on regeneration from in vitro grown plants to purify clones without subjecting the plants to field conditions and harvesting the mature cane. This technique was used to purify transgenic sugarcane plants carrying Bacillus thuringiensis gene.

Establishment of the regeneration system for Vicia faba L.

Science.gov (United States)

Bahgat, Shimaa; Shabban, Omer A; El-Shihy, Osama; Lightfoot, David A; El-Shemy, Hany A

2009-01-01

A reliable regeneration system for faba bean has been difficult to establish and therefore, the genetic improvement of Vicia faba L. was delayed. The paper describes a method of somatic embryo induction in callus of V. faba. Two Egyptian faba bean cultivars 'Giza 2' and '24 Hyto' were used. Callus was induced from epicotyls and shoot tips cultured on MS or Gamborg medium supplemented with 3% sucrose and 0.025% (w/v) for each of ascorbic and citric acid, 0.8% agar and different concentrations of 10 mg/l BAP, 0.5 mg/l of each NAA and 2,4-dichlorophenoxyacetic acid (M1) and 1 mg/l BAP and 0.5 mg/l NAA (M2) . The media with BAP, NAA and 2,4-D were optimal for embryogenic callus induction. Somatic embryos developed after transfer of the callus to 1/2 B5 medium with no plant growth regulators. There were various stages of somatic embryo development present including globular, heart-shaped, torpedo, and cotyledonary stages. Embryos developed into plantlets and plants were regenerated. RAPD analyses were performed to investigate the genetic stability of the regenerated plants obtained from different treatments and different explants. The cultivar Giza 2 exhibited more genetic stability than cultivar 24 Hyto. In conclusion, a regeneration system was established suitable for both gene transformation and the isolation of somaclonal mutants. The regeneration system will be used in order to improve the nutritional value of faba bean.

In vitro propagation of critically endangered species Scilla autumnalis L. – biochemical analyses of the regenerants

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Cristian BANCIU

2010-11-01

Full Text Available The present study belongs to the international efforts for plant conservation from the areas threatened by human activities. The saline soils areas are restricting for agriculture and in some cases for fishery facilities and the plant species are extinct from those areas. Scilla autumnalis L. is one of the threatened plants (rare on the national red list of vascular plants from Romania that grows in the Natural Park Comana, Giurgiu County, South Romania. Seeds from plants grown in the natural habitat have been used for in vitro plant regeneration and multiplication. After successfully rooting and acclimatization of the regenerated plantlets from germinated seeds, biochemical studies have been performed in order to compare the regenerants from in vitro cultures with native plants from genetically point of view. Peroxydase and esterase’s spectra were the biochemical markers used.The results indicated that this plant species can be multiplicated, rooted and acclimatized on synthetic medium (MS supplemented with NAA, IBA, IAA, kinetin and BAP with a good efficiency and the regenerants had no genetic alterations determinated by culture conditions.

Structural diversity, its components and regenerating capacity of lesser Himalayan forests vegetation of Nikyal valley District Kotli (A.K), Pakistan.

Science.gov (United States)

Amjad, Muhammad Shoaib; Arshad, Muhammad; Chaudhari, Sunbal Khalil

2014-09-01

To report the patterns of species diversity, and regenerating capacity in the forest of Nikyal valley in relation to environmental variables and underlying anthropogenic influence. A study area was selected in a traditionally managed mountain woody pasture during July 2012 to June 2013. The area was sampled by quadrat method. The quadrats were laid down at regular intervals of 150 m. The size of quadrats was kept 10×10, 5×5 and 1×1 m(2) for trees, shrubs and herbs respectively. Density, frequency and cover were recorded. Importance value index of each plant species was calculated and plant communities were named after the plant species having the highest IV. Then diversity, its components and regenerating capacity were calculated with their formulas. Shannon's diversity ranged from 2.75 to 3.31, Simpson's diversity, 0.90 to 0.95; Menhinick's diversity, 0.83 to 1.19; evenness, 0.41 to 0.65; species richness, 4.89 to 6.08 and maturity index, 30 to 44 species distribution pattern. Diversity values were similar to the other Himalayan forests. Pinus roxburghaii was the only regenerating species whereas the remaining four tree species including Qurecus dilatata regenerate up to 100 cm; they are at extreme risk of elimination due to anthropogenic factors. Nikyal valley is under severe deforestation pressure for fuel and timber value. There is an urgent need to promote the ethics among the people that improvement and conservation of natural resources are critical for land and soil management. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Robust regeneration protocol for the Agrobacterium tumefaciens mediated transformation of Solanum tuberosum

International Nuclear Information System (INIS)

Abbasi, A.; Bilal, M.; Hussain, J.; Shah, M. M.; Hassan, A.

2016-01-01

Plant genetic transformation requires robust regeneration system. Plant growth regulators (PGRs) such as cytokinins (CKs) play a pivotal role in organogenesis; however, CKs are the most expensive PGRs. In the current study, an efficient yet economical protocol for regeneration of potato plant was developed. Stem inter-nodal and leaf explants were cultured on different regeneration media supplemented with varying concentration of different CKs such as kinetin and zeatin. Murashige- Skoog media added with zeatin (1, 1.5 mg/L) was designated as RZ1, RZ1.5, respectively or kinetin (1.5, 2 mg/L) was designated as RK1.5 and RK2, respectively, however, concentrations of other hormones such as NAA (1-Naphthaleneacetic acid) and GA3 (Gibberellic acid A3) were kept same. RZ1 and RZ1.5 gave significantly better Results as compared to RK-type media in all aspects studied such as callus initiation, days to first shoot emergence, number of shoots per explants. RZ1 medium was then selected as regeneration media for Agrobacterium-mediated transformation of potato plants with cyanobacterial phosphoenol pyruvate carboxylase gene, which provided multiple putative transformants on selection media. The transformants were further confirmed through PCR. The current protocol is found to be cost effective and efficient for the regeneration of Solanum tuberosum and can be successfully implied for the Agrobacterium-mediated transformation. (author)

Micropropagation to Rescue Endangered Plant Moringa Concanensis Nimmo (Moringaceae)

International Nuclear Information System (INIS)

Fatima, H.

2016-01-01

Efficient micropropagation was developed for an endangered plant; Moringa concanensis Nimmo. The plant has many medicinal properties. It is an antioxidant, anti-diabetic and a powerful tonic alternative. A high frequency and maximum number of shoots were produced in MS supplemented with the combination of Benzyl aminopurine (BAP) and Alpha-Naphthalene Acetic Acid (NAA) (0.10mg/l + 0.05mg/l). Rooting was achieved by the inoculation of regenerated shoots on half strength MS without addition of hormone. (author)

Apparatus and methods for regeneration of precipitating solvent

Science.gov (United States)

Liu, Guohai; Vimalchand, Pannalal; Peng, Wan Wang; Bonsu, Alexander

2015-08-25

A regenerator that can handle rich loaded chemical solvent containing precipitated absorption reaction products is disclosed. The invention is particularly suitable for separating CO.sub.2 from large gas streams that are typical of power plant processes. The internally circulating liquid stream in the regenerator (ICLS regenerator) rapidly heats-up the in-coming rich solvent stream in a downcomer standpipe as well as decreases the overall concentration of CO.sub.2 in the mixed stream. Both these actions lead to dissolution of precipitates. Any remaining precipitate further dissolves as heat is transferred to the mixed solution with an inverted bayonet tube heat exchanger in the riser portion of the regenerator. The evolving CO.sub.2 bubbles in the riser portion of the regenerator lead to substantial gas hold-up and the large density difference between the solutions in the downcomer standpipe and riser portions promotes internal circulation of the liquid stream in the regenerator. As minor amounts of solvent components present in the exit gas stream are condensed and returned back to the regenerator, pure CO.sub.2 gas stream exits the disclosed regenerator and condenser system.

Somatic embryogenesis and plant regeneration from cell suspension cultures of Cucumis sativus L.

Science.gov (United States)

Chee, P P; Tricoli, D M

1988-06-01

A procedure for the regeneration of whole cucumber plants (Cucumis sativus L. cv. Poinsett 76) by embryogenesis from cell suspension cultures is described. Embryogenic callus was initiated from the primary leaves of 14-17 day old plants. Suspension cultures of embryogenic cells were grown in liquid Murashige and Skoog basal medium containing 5 uM 2,4,5-trichlorophenoxyacetic acid and 4 uM 6-benzylaminopurine. Suspension cultures were composed of a population of cells that were densely cytoplasmic and potentially embryogenic. Differentiation of embryos was enhanced by washing the suspension culture cells with MS basal medium containing 0.5% activated charcoal and twice with MS basal medium followed by liquid shake cultures in MS basal medium. Sixty to 70 percent of the embryos prewashed with activated charcoal germinated into plantlets with normal morphology. Embryos obtained from suspension cultured cells without prewashing with activated charcoal organized into plantlets with abnormal primary leaves. Morphologically normal plantlets were obtained by excising the shoot tips and transferring them to fresh medium.

Agrobacterium-mediated transformation and direct shoot regeneration in Iranian tomato (Solanum lycopersicum L.) cultivar Falat- CH

International Nuclear Information System (INIS)

Kauser, N.; Khan, S.

2016-01-01

Falat CH is an important commercial tomato cultivar being used in Iran. In this article an optimized protocol with increased transformation and regeneration rate for this tomato variety is reported. Several explants including cotyledon, leaf and hypocotyl were evaluated for direct shoot formation and the effect of various combinations of BAP, Zeatin, IAA and IBA were studied. It is the first report on two cytokinins BAP and Zeatin in various combinations to evaluate the synergetic effect of cytokinins on direct shoot regeneration. The synergetic combination of 1.5mg/l BAP, 0.5 mg/l Zeatin and 0.2 mg/l IAA was considered as the best treatment which resulted in higher plant regeneration rates from all of the explants over previous reported methods. Using the best regeneration treatment obtained, the HBsAg gene was transferred into the tomato explants using Agrobacterium mediated transformation technique Percent of the putative transgenic plants regenerated was 68%. PCR of putative transformed plants showed that 87.1% of regenerated plants amplified nptII and HBsAg gene when specifically designed primers were used giving a final transformation rate of 34.85%. (author)

Agrobacterium rhizogenes-mediated transformation of Superroot-derived Lotus corniculatus plants: a valuable tool for functional genomics

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Liu Wei

2009-06-01

Full Text Available Abstract Background Transgenic approaches provide a powerful tool for gene function investigations in plants. However, some legumes are still recalcitrant to current transformation technologies, limiting the extent to which functional genomic studies can be performed on. Superroot of Lotus corniculatus is a continuous root cloning system allowing direct somatic embryogenesis and mass regeneration of plants. Recently, a technique to obtain transgenic L. corniculatus plants from Superroot-derived leaves through A. tumefaciens-mediated transformation was described. However, transformation efficiency was low and it took about six months from gene transfer to PCR identification. Results In the present study, we developed an A. rhizogenes-mediated transformation of Superroot-derived L. corniculatus for gene function investigation, combining the efficient A. rhizogenes-mediated transformation and the rapid regeneration system of Superroot. The transformation system using A. rhizogenes K599 harbouring pGFPGUSPlus was improved by validating some parameters which may influence the transformation frequency. Using stem sections with one node as explants, a 2-day pre-culture of explants, infection with K599 at OD600 = 0.6, and co-cultivation on medium (pH 5.4 at 22°C for 2 days enhanced the transformation frequency significantly. As proof of concept, Superroot-derived L. corniculatus was transformed with a gene from wheat encoding an Na+/H+ antiporter (TaNHX2 using the described system. Transgenic Superroot plants were obtained and had increased salt tolerance, as expected from the expression of TaNHX2. Conclusion A rapid and efficient tool for gene function investigation in L. corniculatus was developed, combining the simplicity and high efficiency of the Superroot regeneration system and the availability of A. rhizogenes-mediated transformation. This system was improved by validating some parameters influencing the transformation frequency, which could

Modulating wind power plant output using different frequency modulation components for damping grid oscillations

DEFF Research Database (Denmark)

2017-01-01

A method, controller, wind power plant, and computer program product are disclosed for operating a wind power plant comprising a plurality of wind turbines, the wind power plant producing a plant power output. The method comprises receiving a modulation request signal indicating a requested...... modulation of the plant power output, the requested modulation specifying a modulation frequency. The method further comprises generating a respective power reference signal for each of at least two wind turbines of the plurality of wind turbines selected to fulfill the requested modulation, Each generated...... power reference signal includes a respective modulation component corresponding to a portion of the requested modulation and having a frequency different than the modulation frequency....

Evaluation of the capacity for direct regeneration of maize inbreds of the Lancaster selection group

Directory of Open Access Journals (Sweden)

K. V. Derkach

2013-11-01

nonembryogenic and did not lead to regeneration. All explantats were transplanted into fresh nutrient media with simultaneous removal of germinated shoots on the 14th day of cultivation. Regeneration on the 45th day of cultivation took place by direct hemogenesis (formation of shoot or leafy structures or direct hemoryzhogenesis (formation seedlings which had both shoot and root. Formation of ryzhogenic calli was observed in most inbreds. The frequency of regeneration of shoots and leaf structures was characterized by a tendency to increase indicators in the culture environment with mineral basis N6, and the frequency of regeneration of shoots was significantly marked using a medium with mineral basis MS. However, regeneration on the 45th day took place at a much lower rate than on the 14th day of cultivation, which must be taken into account when a system of genetic transformation systems using nodal segments of seedling shoots is being developed. Thus, using nodal sections of 4-day old seedling shoots of maize inbreds of Lancaster germplasm and model inbred Chi31, we can obtain viable seedlings for use in biological systems of agrobacterial transformation. We can recommend two variants of provoking regeneration by direct organogenesis in vitro for application in genetic transformation. The first variant suggests for all studied genotypes 100% induction on the 14th day of in vitro cultivation of direct organogenesis by hemogenesis and this requires further rooting of obtained shoots before planting into soil. Both variants of the nutrient environments of cultivation proposed us can be used. The second variant involves low frequency of regeneration by direct hemoryzhogenesis in a limited number of genotypes, but excludes the rooting stage. The cultivation environment with the mineral basis MS is recommended for this variant. The choice of either variant for obtaining direct regeneration depends on the particularity and aim of the research.

Adventitious shoot regeneration from leaf explants of the valuable ...

African Journals Online (AJOL)

Jane

2011-08-10

Aug 10, 2011 ... 2Department of Plant Biology and Plant Biotechnology, St. Joseph's College, Tiruchirappalli – 620 002, South India. Accepted 28 March, 2011 .... Effect of cytokinins (KN and BAP) alone or in combination with NAA on direct shoot bud regeneration from leaf explants of P. barbatus. Plant growth regulator ...

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.

Vegetation structure and composition of a tropical dry forest in regeneration in Bataclán (Cali, Colombia

Directory of Open Access Journals (Sweden)

Viviana Londoño Lemos

2015-01-01

Full Text Available Characterization of long-term vegetation in a tropical dry forest (TDF that is in the process of regeneration permits establishment of patterns of composition, structure and dynamics of plant communities and sheds light on the different stages of plant succession. In this study, the plant community of ecoparque Bataclán, Cali, Colombia was evaluated by determining its structure and composition in two regeneration strategies. One strategy consisted of natural regeneration with bamboo barriers and the other of natural regeneration without bamboo barriers. Three permanent plots of 500 m2 were established in each regeneration strategy (six plots in total. Composition and structure was determined, taking into account all the growth habits, with different sampling methods. We found no significant differences between vegetation structure and composition of the two strategies for forest regeneration. forty-one species belonging to 27 families were recorded (trees and shrubs 58.5 %, herbs 24.4 %, climbers or scandents 14.6 %, epiphytes 2.4 %. The dominant family was Melastomataceae and the dominant species was Miconia prasina. The orchidCatasetum ochraceum and the grass Thrasya petrosa were indicator species for high luminosity. We conclude that the plant community is in an early successional stage, where there is a mixture of planted and naturally regenerated species in the zone, characterized by pioneer species from TDF and other nearby life zones.

System for processing ion exchange resin regeneration waste liquid in atomic power plant

International Nuclear Information System (INIS)

Onaka, Noriyuki; Tanno, Kazuo; Shoji, Saburo.

1976-01-01

Object: To reduce the quantity of radioactive waste to be solidified by recovering and repeatedly using sulfuric acid and sodium hydroxide which constitute the ion exchange resin regeneration waste liquid. Structure: Cation exchange resin regeneration waste liquid is supplied to an anion exchange film electrolytic dialyzer for recovering sulfuric acid through separation from impurity cations, while at the same time anion exchange resin regeneration waste liquid is supplied to a cation exchange film electrolytic dialyzer for recovering sodium hydroxide through separation from impurity anions. The sulfuric acid and sodium hydroxide thus recovered are condensed by a thermal condenser and then, after density adjustment, repeatedly used for the regeneration of the ion exchange resin. (Aizawa, K.)

An Integrated Strategy to Identify Key Genes in Almond Adventitious Shoot Regeneration

Science.gov (United States)

Plant genetic transformation usually depends on efficient adventitious regeneration systems. In almond (Prunus dulcis Mill.), regeneration of transgenic adventitious shoots was achieved but with low efficiency. Histological studies identified two main stages of organogenesis in almond explants that ...

Dynamic Frequency Response of Wind Power Plants

DEFF Research Database (Denmark)

Altin, Müfit

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...... 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...... capability of WPPs would be investigated. The objective of this project is to analyze and identify the power system requirements for the synchronizing power support and inertial response control of WPPs in high wind power penetration scenarios. The dynamic frequency response of WPPs is realized...

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

International Nuclear Information System (INIS)

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

Optimization of Protocols for In Vitro Regeneration of Sugarcane (Saccharum officinarum

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Shakra Jamil

2017-01-01

Full Text Available Sugarcane contributes 60–70% of annual sugar production in the world. Somaclonal variation has potential to enhance genetic variation present within a species. Present study was done to optimize an in vitro propagation protocol for sugarcane. The experiments included four varieties, 9 callus induction media, 27 regeneration media, and 9 root induction media under two-factor factorial CRD. Data were recorded on callus induction, embryogenic callus formation, shoot elongation (cm, root induction, and plant regeneration. Statistically significant differences existed between genotypes and treatments for callus induction (%, embryogenic callus formation (%, shoot elongation (cm, root induction, and plant regeneration (%. All parameters showed dependency on genotypes, culture media, and their interaction. Highest callus induction (95% embryogenic callus formation (95% was observed in callus induction media 5. Highest plantlet regeneration (98.9% capacity was observed in regeneration media 11 whereas maximum shoot elongation (12.13 cm and root induction (8.32 were observed in rooting media 4. G1 showed best response for all traits and vice versa for G4. Hence it was concluded that G1, callus induction media 5, regeneration media 11, and rooting media 4 are the best conditions for in vitro propagation of sugarcane.

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

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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.

Optimization of callus induction and plant regeneration from ...

African Journals Online (AJOL)

An efficient regeneration system was developed using germinating seeds of two cultivars of sweet sorghum, Sorghum bicolor 'Yuantian No.1' and 'M81E', as explants. We tested different media supplements effects on callus induction. The effects of combinations of 2,4-D, KT, sucrose, agar and proline at different ...

Efficient in vitro propagation of Artemisia nilagirica var. nilagirica (Indian wormwood) and assessment of genetic fidelity of micropropagated plants.

Science.gov (United States)

Shinde, Smita; Sebastian, Joseph Kadanthottu; Jain, Jyothi Ramesh; Hanamanthagouda, Manohar Shirugumbi; Murthy, Hosakatte Niranjana

2016-10-01

A reliable protocol has been established for in vitro propagation of Artemisia nilagirica var. nilagirica (Indian wormwood), a valuable medicinal plant from India. A highly proliferating organogenic callus was obtained on Murashige and Skoog (MS) medium supplemented with 2.5 µM IAA when nodal explants were cultured on MS medium supplemented with various growth regulators. Further, highest regeneration frequency (83.3 %) of adventitious shoots was observed, when the callus was sub-cultured on MS medium supplemented with 6-benzylaminopurine (BAP; 2.5 µM) along with 7.5 µM 2-isopentenyl adenine (2-iP). An optimal of 10.16 ± 2.24 shoots were regenerated on medium supplemented with 2.5 µM BAP + 7.5 µM 2-iP. Quarter strength MS medium supplemented with 10 µM IBA was effective for rooting of the shoots. Ex-vitro plants were normal and were established successfully. Cytological and molecular marker studies showed that regenerated plants showed genetic stability in micro-propagated plants.

Plant regeneration from leaf protoplasts of Solanum torvum.

Science.gov (United States)

Guri, A; Volokita, M; Sink, K C

1987-07-01

A protocol to obtain regenerated plants from protoplasts of Solanum torvum Sw a wild species of eggplant resistant to Verticillium wilt is reported. Leaf protoplasts were enzymatically isolated from six-week old seedlings grown in a controlled environment chamber. Protoplasts were plated on modified KM medium (0.4 M glucose)+(mg/l): 1.0 p-chlorophenoxyacetic acid (CPA)+1.0 naphthaleneacetic acid (NAA)+0.5 6-benzylaminopurine (BAP) and 0.02 abscisic acid (ABA). The protoplast density was 5×10(4) per ml with 5 ml placed in each of two quadrants in X-dishes (100×15 mm). The reservoir medium was modified KM+(mg/l): 0.1 NAA+0.5 BAP+0.1 M sucrose+0.1 M mannitol+0.6% washed agar+1% activated charcoal. Dishes were initially placed in the dark at 27°C. Protoplast division was initiated in 1-2 weeks and 4 weeks later p-calli were 1-3 mm. Plating efficiency was 11% when measured at 3 weeks. Six-week old p-calli were transferred individually onto Whatman No. 1 filter paper layered on modified KM (0.15 M sucrose)+mg/l: 2.0 indoleacetic acid (IAA)+2.0 zeatin+0.5% washed agar for 2 weeks. Subsequently, shoots occurred within 4 weeks at 70% efficiency on MS+30 g/l sucrose+2 mg/l zeatin. Shoots were rooted on half strength MS+10 g/l sucrose.

In vitro regeneration of Drosera burmannii Vahl.: a carnivorous plant of north-east India.

Science.gov (United States)

Yanthan, J Sureni; Kehie, Mechuselie; Kumaria, Suman; Tandon, Pramod

2017-06-01

An efficient in vitro regeneration protocol has been developed from shoot tips of Drosera burmannii Vahl., a carnivorous plant of north-east India. Various plant growth regulators were used to study their efficacy in the induction of multiple shoots and roots. Of the various treatments, the maximum number of shoots (28.8 ± 1.5) and roots (9.7 ± 0.6) was observed in one-fourth strength standard medium (MS with 50 mg/l citric acid and 10 mg/l ascorbic acid) supplemented with 4 mg/l 6-benzylaminopurine (BAP) and 4 mg/l α-naphthalene acetic acid (NAA) followed by 26.8 ± 1.4 shoots in one-fourth strength SM fortified with 4 mg/l kinetin (KN) and 4 mg/l NAA. The well-developed plantlets with shoots and roots were potted in small plastic glasses filled with a mixture of sand and farmyard manure (3:1); these plantlets when transferred to a glasshouse for hardening and acclimatization showed 90% survival.

The role of neurotrophic factors in nerve regeneration.

Science.gov (United States)

Gordon, Tessa

2009-02-01

This review considers the 2 sources of neurotrophic factors in the peripheral nervous system (PNS), the neurons and the nonneuronal cells in the denervated distal nerve stumps, and their role in axon regeneration. Morphological assessment of regenerative success in response to administration of exogenous growth factors after nerve injury and repair has indicated a role of the endogenous neurotrophic factors from Schwann cells in the distal nerve stump. However, the increased number of axons may reflect more neurons regenerating their axons and/or increased numbers of axon sprouts from the same number of neurons. Using fluorescent dyes to count neurons that regenerated their axons across a suture site and into distal nerve stumps, brain-derived neurotrophic factor (BDNF) and glial cell-derived neurotrophic factor (GDNF) were found not to increase the number of neurons that regenerated their axons after immediate nerve repair. Nevertheless, the factors did reverse the deleterious effect of delayed nerve repair, indicating that the axons that regenerate into the distal nerve stump normally have access to sufficient levels of endogenous neurotrophic factors to sustain their regeneration, while neurons that do not have access to these factors require exogenous factors to sustain axon regeneration. Neurons upregulate neurotrophic factors after axotomy. The upregulation is normally slow, beginning after 7 days and occurring in association with a protracted period of axonal regeneration in which axons grow out from the proximal nerve stump across a suture site over a period of 1 month in rodents. This staggered axon regeneration across the suture site is accelerated by a 1-hour period of low-frequency electrical stimulation that simultaneously accelerates the expression of BDNF and its trkB receptor in the neurons. Elevation of the level of BDNF after 2 days to > 3 times that found in unstimulated neurons was accompanied by elevation of the level of cAMP and followed by

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

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.

ADAPTATION OF REGENERANTS OF Vaccinium Corymbosum L

African Journals Online (AJOL)

Kutas

2011-05-09

May 9, 2011 ... Adaptation of regenerants of Vaccinium corymbosum ... functions of the sheet plants growing in an aseptic culture, in hothouses or open ground .... L. (Koralle) were preserved in alcohol-acetic acid (3:1). ..... and soil moisture.

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.

Plantlet regeneration potential from seedling explants of vitegnus (Vitex agnus castus).

Science.gov (United States)

Chamandoosti, F

2007-11-15

In this research a simple and repeatable method for regeneration of a important medicinal plant (Vitex agnus castus) described. Different seedling explants such as hypocotyl, cotyledon, root and apical meristem were cultured in MS basal media with different kinds and concentrations of PGRs. Root and apical meristem explants were the only explants that have regeneration whole plantlets potential. It was interesting that regeneration whole plantlets from root and apical meristem explants have different developmental pathways. Whole plantlets from apical meristem explants regenerated by passing phase callusing whereas regeneration whole plantlets from root was direct and without phase callusing. This subject implies that we can have many manipulation possibilities in order to different objects of tissue culture by selecting different explants in vitegnus.

Systematic analysis of plant disturbances with a view to reducing scram frequency

International Nuclear Information System (INIS)

Laakso, K.J.

1984-01-01

The goal of this project is to improve plant safety and reliability in Swedish BWRs by reducing the frequency of reactor scrams. The history of plant disturbances leading to reactor scrams and turbine trips in five Swedish nuclear power units was reviewed and the contributing causes were carefully analyzed. A total of 625 plant disturbances was included in the search. Improvements to be made in the units were identified and the merits of possible modifications were assessed using reliability engineering and PRA techniques. Emphasis was given to design improvements in the NSSS (Nuclear Steam Supply System) as well as in the electricity generation (turbine plant) area. Examples of various types of recommended modifications will be given, including either their proven or expected efficiency in reducing scram frequency. (orig./HP)

The impact of Cu treatment on phenolic and polyamine levels in plant material regenerated from embryos obtained in anther culture of carrot

Czech Academy of Sciences Publication Activity Database

Górecka, K.; Cvikrová, Milena; Kowalska, U.; Eder, Josef; Szafrańska, K.; Górecki, R.; Janas, K. M.

2007-01-01

Roč. 45, č. 1 (2007), s. 54-61 ISSN 0981-9428 R&D Projects: GA MŠk 1P05OC052 Institutional research plan: CEZ:AV0Z50380511 Source of funding: V - iné verejné zdroje Keywords : carrot culture * copper ions * embryo regeneration Subject RIV: GE - Plant Breeding Impact factor: 1.669, year: 2007

An energy storage and regeneration system

DEFF Research Database (Denmark)

2006-01-01

  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...... 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 higher level of energy demand....

Regeneration and genetic transformation of cowpea (Vigna unguiculata Walp.)

Energy Technology Data Exchange (ETDEWEB)

Filippone, E; Colucci, G; Ciardi, F; Monti, L [Department of Agronomy and Plant Genetics, Univ. of Naples Federico 11, Portici (Italy)

1997-07-01

Regeneration of cowpea (Vigna unguiculata Walp.) was achieved through massive bud formation induced in apical and lateral meristems by the herbicide Thidiazuron (TDZ). The effect of TDZ (5, 10, or 20 {mu}M) was tested in vitro on four different cowpea genotypes. Thidiazuron, even at the highest concentration, had no effect on seed germination. After one month of culture, multiple bud cluster formation was observed in all genotypes tested; about 80% of shoot apices regenerated multiple buds, whilst only 34% of cotyledonary nodes behaved in the same way. Histology of regenerating multiple bud clusters revealed that regeneration initiated from pre-existing meristems in the apex and cotyledonary node. Thidiazuron at 10 {mu}M appeared to be the best concentration to produce clusters with high number of buds, ranging from 5 to 10. Shoot elongation occurred only on MS medium without TDZ. On the same medium, 75% of elongated shoots rooted. For genetic transformation of cowpea, a direct DNA transfer methods in plants under in vivo conditions was tested by electroporation of plasmid DNA into the nodal meristematic cells. Some transformed plants were obtained, and produced T{sub 1} transformed progenies; their transgenic nature was confirmed by Southern analysis. (author). 21 refs, 2 figs, 3 tabs.

Regeneration and genetic transformation of cowpea (Vigna unguiculata Walp.)

International Nuclear Information System (INIS)

Filippone, E.; Colucci, G.; Ciardi, F.; Monti, L.

1997-01-01

Regeneration of cowpea (Vigna unguiculata Walp.) was achieved through massive bud formation induced in apical and lateral meristems by the herbicide Thidiazuron (TDZ). The effect of TDZ (5, 10, or 20 μM) was tested in vitro on four different cowpea genotypes. Thidiazuron, even at the highest concentration, had no effect on seed germination. After one month of culture, multiple bud cluster formation was observed in all genotypes tested; about 80% of shoot apices regenerated multiple buds, whilst only 34% of cotyledonary nodes behaved in the same way. Histology of regenerating multiple bud clusters revealed that regeneration initiated from pre-existing meristems in the apex and cotyledonary node. Thidiazuron at 10 μM appeared to be the best concentration to produce clusters with high number of buds, ranging from 5 to 10. Shoot elongation occurred only on MS medium without TDZ. On the same medium, 75% of elongated shoots rooted. For genetic transformation of cowpea, a direct DNA transfer methods in plants under in vivo conditions was tested by electroporation of plasmid DNA into the nodal meristematic cells. Some transformed plants were obtained, and produced T 1 transformed progenies; their transgenic nature was confirmed by Southern analysis. (author). 21 refs, 2 figs, 3 tabs

Enhancement of callus induction and regeneration efficiency from ...

African Journals Online (AJOL)

Administrator

2011-09-05

Sep 5, 2011 ... efficiency from embryo cultures of Datura stramonium ... cycle (callus induction and plant regeneration) for Datura stramonium by adjusting carbon sources and ... induction and development in various species, it is not.

STUDIES REGARDING CULTURE MEDIUM INFLUENCE ON IN VITRO REGENERATION FROM WHEAT IMATURE EMBRYOS

Directory of Open Access Journals (Sweden)

M. DANCI

2008-05-01

Full Text Available Surnamed „embryos’ saving method”, embryos culture is an in vitro technique used for over half of the century for saving the distant hybridization products, that would have degenerate in other conditions. Immature embryos culture is used for initiation of in vitro cultures imposed by the impossibility of using other explants for some of the plant species. Wheat is one of the crops that immature embryos culture technique is suitable for. This methods principle is based on aseptic embryos excision and their inoculation to an adequate culture medium. In vitro culture results depend in a greater manner of the basic culture medium and the hormonal balance used. Immature embryos isolated from two Romanian wheat cultivars – Dropia and Lovrin 41 – were inoculated for callus production on two types of basic media added with 2,4 D. The selected calluses were transferred on MS basic medium and several parameters were registered. Both cultivars emphasized a good callusing capacity, in a different percentage depending on the culture media used, such as 71,09 – 94,45%.. big differences between the cultivars regarding embriogenic callus frequency, shooting callus frequency and regenerated plants percentage were registered.

Prolific plant regeneration through organogenesis from scalps of ...

African Journals Online (AJOL)

Four types of potting media comprising of sand, peat, sand + top soil + goat dung (3:2:1 v/v) and top soil + sand (1:1 v/v) were evaluated during acclimatization of the plantlets. Prolific shoot regeneration from scalps was obtained on MS medium containing 2.5 mM BAP, at 9.61 and 40.6 shoots per explant after 4 and 8 weeks ...

Modification and optimisation measures on the demineralisation plant of the Boxberg Power Station; Umbau und Optimierung der Vollentsalzungsanlage im Kraftwerk Boxberg

Energy Technology Data Exchange (ETDEWEB)

Leidich, F.U. [ALSTOM Power Generation AG, Mannheim (Germany); Markert, A. [Vattenfall Europe Generation AG Co KG, E-KT, Cottbus (Germany); Hajdamowicz, S. [Vattenfall Europe Generation AG Co KG, E-GBB, Boxberg (Germany); Kleespies, W. [RoKa GmbH, Butzbach (Germany)

2006-07-01

The demineralisation plant at the Boxberg Power Station, Unit AQ (Plant IV), owned by Vattenfall Europe Generation AG and Co KG, officially started its operation in 2000. In the course of the operation, technical shortcomings became apparent that rendered the quality of the deionised water inadequate and did prevent the plant from being operated in a normal, fully-automatic mode. Due to the insolvency of the supplier, it had not been possible to eliminate a series of problems and optimise the processes in such a way that the plant could be operated as planned. Nevertheless, thanks to measures like retrofitting the system with lowering loops, replacing the regenerating stations by frequency-controlled excenter-screw propeller pumps, installing automatic vents, and optimising the control concept of the plant, it finally was possible to solve some of the main problems. Longer intervals between regenerating procedures came as an additional benefit. (orig.)

Penetration of nanoparticles in flax (Linum usitatissimum L.) calli and regenerants.

Science.gov (United States)

Kokina, Inese; Gerbreders, Vjačeslavs; Sledevskis, Eriks; Bulanovs, Andrejs

2013-05-20

We demonstrate a method for direct delivery of metal nanoparticles to flax calli and regenerant cells by vacuum deposition of metal nanolayers on powdered hormone followed by dispersal of the combined hormone-metal in medium. The penetration and location of the gold (AuNPs) and silver (AgNPs) nanoparticles in calli and in plant regenerants were confirmed by optical absorption spectroscopy and scanning electron microscopy. We detected a significant effect of the AuNPs and AgNPs on the regeneration type of flax calli. Copyright © 2013 Elsevier B.V. All rights reserved.

ICT based Performance Evaluation of Primary Frequency Control Support from Renewable Power Plants in Smart Grids

DEFF Research Database (Denmark)

Shahid, Kamal; Altin, Müfit; Mikkelsen, Lars Møller

2018-01-01

frequency control support from ReGen plants will highly depend on the underlying communication infrastructure that allows an exchange of information between different ReGen plants and the control centers. This paper, therefore, focuses on the impact of communication and the related aspects to provide online...... plants towards ReGen plants, such as wind and photovoltaic power plants. Frequency control support from the Wind Power Plants (WPPs) is one of the crucial ancillary services in order to preserve operational stability in case of grid disturbances. Among other requirements, the ability to provide fast...... wind speeds at a particular wind-power penetration level and communication scenarios are considered to evaluate the performance of power system frequency response. The article provides the Transmission System Operator (TSO) and other communication engineers insights into the importance and various...

In vitro regeneration of a common medicinal plant, Ocimum sanctum ...

African Journals Online (AJOL)

aristo_team

brings down circulatory strain, mitigates cardiovascular depressant, is antiulcer, fights .... DISCUSSION. Proficient regeneration systems are vital for hereditary. 0. 10. 20 .... Hao D, Xiao P (2015). Genomics and Evolution in Traditional Medicinal.

Regeneration of nitrobenzene-exhausted granular activated carbon by dielectric barrier discharge method

International Nuclear Information System (INIS)

Lan, Tian; Gao, Wenli; Li, Zhongjian; Lei, Lecheng

2013-01-01

A novel method for the regeneration of nitrobenzene-exhausted granular activated carbon using dielectric barrier discharge (DBD) was proposed in this study. The influence of several parameters including voltage, frequency, and plasma medium on the regeneration efficiency were studied. Under optimum conditions, regeneration efficiency can reach over 80% and remain nearly stable after 5 times of regeneration cycle. The texture characteristic and surface chemistry of Granular Activated Carbon (GAC) samples were also investigated. Analysis shows that the pore volume and specific surface area of regenerated GAC is strongly recovered compared to the exhausted GAC, but the discharge can cause some pores to diminish. Acidic functional groups on GAC's surface especially carboxylic groups had a growing tendency after DBD process. Experimental results show that the regeneration of GAC by DBD method mainly attributes to high active species and thermal effect, while O 3 has minor effect.

ICT based Performance Evaluation of Primary Frequency Control Support from Renewable Power Plants in Smart Grids

DEFF Research Database (Denmark)

Shahid, Kamal; Altin, Müfit; Mikkelsen, Lars Møller

2018-01-01

frequency control support from ReGen (with special focus on WPP). The study is conducted with an aggregated WPP model, integrated into a generic power system model, specifically designed to assess the ancillary services in a relatively simple yet relevant environment. Various case studies with different...... plants towards ReGen plants, such as wind and photovoltaic power plants. Frequency control support from the Wind Power Plants (WPPs) is one of the crucial ancillary services in order to preserve operational stability in case of grid disturbances. Among other requirements, the ability to provide fast...... frequency control support from ReGen plants will highly depend on the underlying communication infrastructure that allows an exchange of information between different ReGen plants and the control centers. This paper, therefore, focuses on the impact of communication and the related aspects to provide online...

Natural regeneration in abandoned fields following intensive agricultural land use in an Atlantic Forest Island, Brazil

Directory of Open Access Journals (Sweden)

Milene Silvestrini

2012-08-01

Full Text Available The time required to regrowth a forest in degraded areas depends on how the forest is removed and on the type of land use following removal. Natural regeneration was studied in abandoned old fields after intensive agricultural land use in areas originally covered by Brazilian Atlantic Forests of the Anchieta Island, Brazil in order to understand how plant communities reassemble following human disturbances as well as to determine suitable strategies of forest restoration. The fields were classified into three vegetation types according to the dominant plant species in: 1 Miconia albicans (Sw. Triana (Melastomataceae fields, 2 Dicranopteris flexuosa (Schrader Underw. (Gleicheniaceae thickets, and 3 Gleichenella pectinata (Willd. Ching. (Gleicheniaceae thickets. Both composition and structure of natural regeneration were compared among the three dominant vegetation types by establishing randomly three plots of 1 x 3 m in five sites of the island. A gradient in composition and abundance of species in natural regeneration could be observed along vegetation types from Dicranopteris fern thickets to Miconia fields. The gradient did not accurately follow the pattern of spatial distribution of the three dominant vegetation types in the island regarding their proximity of the remnant forests. A complex association of biotic and abiotic factors seems to be affecting the seedling recruitment and establishment in the study plots. The lowest plant regeneration found in Dicranopteris and Gleichenella thickets suggests that the ferns inhibit the recruitment of woody and herbaceous species. Otherwise, we could not distinguish different patterns of tree regeneration among the three vegetation types. Our results showed that forest recovery following severe anthropogenic disturbances is not direct, predictable or even achievable on its own. Appropriated actions and methods such as fern removal, planting ground covers, and enrichment planting with tree species were

Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

Directory of Open Access Journals (Sweden)

Óscar Concepción Laffitte

2004-07-01

Full Text Available Adventitious regeneration is a key step in the application of genetic engineering to the breeding programs of plants. In this work a method for adventitious shoot regeneration from leaves of micropropagated guava shoots has been developed and some of main factors to affect the shoot regeneration like, concentration of plant growth regulators (citoquinine, physiological state of explants and the wound are studied. Leaves from guava in vitro cultured of variety Cuban Red Dwarf 18-40 was used like explant in all experiments. The best re-sult was reached with MS basal medium supplemented with 0.75 mg/L of 6-benzylaminopurine. Was de-monstrated that for the leaves with more multiplication subculture number and taken from lower part of shoot (older; the morfogenetic potential falls significantly (p60% and the largest number of shoot per regenerating leaf (>3 were obtained with several wounds carried out in f orm of jabs to the central nerve of leaves. This regeneration protocol constitutes an important tool that can be applied for future studies of genetic transformation in this species. Key words: Tissue culture, leaf explants, growth regulators, organogenesis, guava

Fire severity filters regeneration traits to shape community assembly in Alaska's boreal forest.

Directory of Open Access Journals (Sweden)

Teresa N Hollingsworth

Full Text Available Disturbance can both initiate and shape patterns of secondary succession by affecting processes of community assembly. Thus, understanding assembly rules is a key element of predicting ecological responses to changing disturbance regimes. We measured the composition and trait characteristics of plant communities early after widespread wildfires in Alaska to assess how variations in disturbance characteristics influenced the relative success of different plant regeneration strategies. We compared patterns of post-fire community composition and abundance of regeneration traits across a range of fire severities within a single pre-fire forest type- black spruce forests of Interior Alaska. Patterns of community composition, as captured by multivariate ordination with nonmetric multidimensional scaling, were primarily related to gradients in fire severity (biomass combustion and residual vegetation and secondarily to gradients in soil pH and regional climate. This pattern was apparent in both the full dataset (n = 87 sites and for a reduced subset of sites (n = 49 that minimized the correlation between site moisture and fire severity. Changes in community composition across the fire-severity gradient in Alaska were strongly correlated to variations in plant regeneration strategy and rooting depth. The tight coupling of fire severity with regeneration traits and vegetation composition after fire supports the hypothesis that disturbance characteristics influence patterns of community assembly by affecting the relative success of different regeneration strategies. This study further demonstrated that variations in disturbance characteristics can dominate over environmental constraints in determining early patterns of community assembly. By affecting the success of regeneration traits, changes in fire regime directly shape the outcomes of community assembly, and thus may override the effects of slower environmental change on boreal forest

Auxin-cytokinin synergism in vitro for producing genetically stable plants of Ruta graveolens using shoot tip meristems

Directory of Open Access Journals (Sweden)

Mohammad Faisal

2018-02-01

Full Text Available An efficient micropropagation protocol was developed for Ruta graveolens Linn. using shoot tip meristems derived from a 4-month-old field grown plant. In vitro shoot regeneration and proliferation was accomplished on Murashige and Skoogs (MS semi-solid medium in addition to different doses of cytokinins viz.6- benzyl adenine (BA, Kinetin (Kn or 2-isopetynyl adenine (2iP, singly or in combination with auxins viz. indole-3-acetic acid (IAA, indole-3-butyric acid (IBA or α-naphthalene acetic acid (NAA. Highest regeneration frequency (27.6% was obtained on (MS medium composed of BA (10 µM with maximum number (9.4 of shoots and 4.3 cm shoot length after 4 weeks of incubation. Among various combinations tried best regeneration frequency (71% of multiple shoot formation with highest number (12.6 of shoots per shoot tip explants were achieved in MS medium augmented with a combination BA (10.0 µM and NAA (2.5 µM after 4 weeks of incubation. The optimum frequency (97% of rhizogenesis was achieved on half-strength MS medium having 0.5 µM IBA after 4 weeks of incubation. Tissue culture raised plantlets with 5–7 fully opened leaves with healthy root system were successfully acclimatized off in Soilrite™ with 80% survival rate followed by transportation to normal soil under natural light. Genetic stability among in vitro raised progeny was evaluated by ISSR and RAPD markers. The entire banding pattern revealed from in vitro regenerated plants was monomorphic to the donor. The present protocol provides an alternative option for commercial propagation and fruitful setting up of genetically uniform progeny for sustainable utilization and germplasm preservation.

Fire frequency and tree canopy structure influence plant species diversity in a forest-grassland ecotone

Science.gov (United States)

David W. Peterson; Peter B. Reich

2008-01-01

Disturbances and environmental heterogeneity are two factors thought to influence plant species diversity, but their effects are still poorly understood in many ecosystems. We surveyed understory vegetation and measured tree canopy cover on permanent plots spanning an experimental fire frequency gradient to test fire frequency and tree canopy effects on plant species...

An Efficient In Vitro Regeneration System for Ornamental Ginger (Hedychium spp.)

Science.gov (United States)

An improved and efficient regeneration protocol was established for Hedychium via somatic embryogenesis. The plant material used consisted of 11 species and 9 cultivars of Hedychium. The explants consisted of young leaves taken from lateral or terminal shoots of mature greenhouse grown plants. These...

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.

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

In vitro plant regeneration from Narbon Vetch (Vicia narbonensis L ...

African Journals Online (AJOL)

STORAGESEVER

2008-07-18

Jul 18, 2008 ... regeneration from cotyledonary node explants obtained from, in vitro raised seeds of 4 - 5 and 14 - 15 days old .... shoots in Vicia faba using different concentrations of. BAP-TDZ. ... feed legume crop for dry areas in west Asia.

Oral Mucosa Harbors a High Frequency of Endothelial Cells: A Novel Postnatal Cell Source for Angiogenic Regeneration.

Science.gov (United States)

Zhou, Jian; Rogers, Jason H; Lee, Scott H; Sun, DongMing; Yao, Hai; Mao, Jeremy J; Kong, Kimi Y

2017-01-15

Endothelial progenitor cells/endothelial cells (EPCs/ECs) have great potential to treat pathological conditions such as cardiac infarction, muscle ischemia, and bone fractures, but isolation of EPC/ECs from existing cell sources is challenging due to their low EC frequency. We have isolated endothelial progenitor (EP)-like cells from rat oral mucosa and characterized their yield, immunophenotype, growth, and in vivo angiogenic potential. The frequency of EP-like cells derived from oral mucosa is thousands of folds higher than EPCs derived from donor-match bone marrow samples. EP-like cells from oral mucosa were positive for EC markers CD31, VE-Cadherin, and VEGFR2. Oral mucosa-derived EP-like cells displayed robust uptake of acetylated low-density lipoprotein and formed stable capillary networks in Matrigel. Subcutaneously implanted oral mucosa-derived EP-like cells anastomosed with host blood vessels, implicating their ability to elicit angiogenesis. Similar to endothelial colony-forming cells, EP-like cells from oral mucosa have a significantly higher proliferative rate than human umbilical vein endothelial cells. These findings identify a putative EPC source that is easily accessible in the oral cavity, potentially from discarded tissue specimens, and yet with robust yield and potency for angiogenesis in tissue and organ regeneration.

Somatic embryogenesis and plant regeneration in Carica papaya L. tissue culture derived from root explants.

Science.gov (United States)

Chen, M H; Wang, P J; Maeda, E

1987-10-01

The regeneration potential of shoot tip, stem, leaf, cotyledon and root explants of two papaya cultivars (Carica papaya cv. 'Solo' and cv. 'Sunrise') were studed. Callus induction of these two cultivars of papaya showed that the shoot tips and stems are most suitable for forming callus, while leaves, cotyledons and roots are comparatively difficult to induce callus. Callus induction also varied with the varities. Somatic embryogenesis was obtained from 3-month-old root cultures. A medium containing half strength of MS inorganic salts, 160 mg/l adenine sulfate, 1.0 mg/1 NAA, 0.5 mg/1 kinetin and 1.0 mg/1 GA3 was optimal for embryogenesis. The callus maintained high regenerative capacity after two years of culture on this medium. Plants derived from somatic embryos were obtained under green-house conditions.

The influence of vapor superheating on the level of heat regeneration in a subcritical ORC coupled with gas power plant

Science.gov (United States)

Wiśniewski, Sławomir; Borsukiewicz-Gozdur, Aleksandra

2010-09-01

The authors presented problems related to utilization of exhaust gases of the gas turbine unit for production of electricity in an Organic Rankine Cycle (ORC) power plant. The study shows that the thermal coupling of ORC cycle with a gas turbine unit improves the efficiency of the system. The undertaken analysis concerned four the so called "dry" organic fluids: benzene, cyclohexane, decane and toluene. The paper also presents the way how to improve thermal efficiency of Clausius-Rankine cycle in ORC power plant. This method depends on applying heat regeneration in ORC cycle, which involves pre-heating the organic fluid via vapour leaving the ORC turbine. As calculations showed this solution allows to considerably raise the thermal efficiency of Clausius-Rankine cycle.

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

Allowable shipment frequencies for the transport of toxic gases near nuclear power plants

International Nuclear Information System (INIS)

Bennett, D.E.; Heath, D.C.

1982-10-01

One part of the safety analysis of offsite hazards for a nuclear power plant is consideration of accidents which could release toxic gases or vapors and thus jeopardize plant safety through incapacitation of the control room operators. The purpose of this work is to provide generic, bounding estimates of the maximum allowable shipping frequencies for the transport of a chemical near the plant, such that the regulatory criteria for the protection of the operators are met. A probabilistic methodology was developed and then applied to the truck and rail transport of an example chemical, chlorine. The current regulatory criteria are discussed in detail. For this study, a maximum allowable probability of occurrence of operator incapacitation of 10 - 5 per year was used in the example calculation for each mode of transport. Comprehensive tables of conditional probabilities are presented. Maximum allowable ahipping frequencies are then derived. These frequencies could be used as part of a generic, bounding criterion for the screening of toxic hazards safety analyses. Unless a transport survey assures shipping frequencies within 8 km of the plant on the order of or lower than 4/week for rail or 35/week for truck, the contol room should be isolatable and the shipping frequency then determines the degree of isolation needed. The need for isolation implies the need for toxic chemical detection at the air intake.For a self-detection case in which the smell threshold is significantly lower than the incapacitation threshold and the control room is isolatable, the corresponding trequencies are 11/week for rail or 115/week for truck. Self-contained breathing equipment is assumed to be used after 5 minutes

Enhanced regeneration in explants of tomato (Lycopersicon ...

African Journals Online (AJOL)

USER

2010-06-14

Jun 14, 2010 ... The development of a cost effective and efficient protocol for mass propagation of high quality tomato seedlings via tissue culture could help to reduce the price per seedling. A good in vitro plant regeneration system may also assist in further improvement of the commercially important cultivars for disease.

ICT Based Performance Evaluation of Primary Frequency Control Support from Renewable Power Plants in Smart Grids

Directory of Open Access Journals (Sweden)

Kamal Shahid

2018-05-01

Full Text Available The increased penetration of Renewable Energy Generation (ReGen plants in future power systems poses several challenges to the stability of the entire system. In future green energy rich power systems, the responsibility for providing ancillary services will be shifted from conventional power plants towards ReGen plants, such as wind and photovoltaic power plants. Frequency control support from the Wind Power Plants (WPPs is one of the crucial ancillary services in order to preserve operational stability in case of grid disturbances. Among other requirements, the ability to provide fast frequency control support from ReGen plants will highly depend on the underlying communication infrastructure that allows an exchange of information between different ReGen plants and the control centers. This paper, therefore, focuses on the evaluation of the impact of communication and the related aspects to provide online frequency control support from ReGen (with special focus on WPP. The performance evaluation is based on an aggregated WPP model that is integrated into a generic power system model. This generic power system model is specifically designed to assess the ancillary services in a relatively simple yet relevant environment. Several case studies with different wind speeds at a particular wind-power penetration level and communication scenarios are considered to evaluate the performance of power system frequency response. The article provides the Transmission System Operator (TSO and other communication engineers insights into the importance and various aspects of communication infrastructure for general service coordination between WPPs and specifically primary frequency control coordination from WPPs in future power systems.

De novo assembly of plant body plan: a step ahead of Deadpool.

Science.gov (United States)

Kareem, Abdul; Radhakrishnan, Dhanya; Sondhi, Yash; Aiyaz, Mohammed; Roy, Merin V; Sugimoto, Kaoru; Prasad, Kalika

2016-08-01

While in the movie Deadpool it is possible for a human to recreate an arm from scratch, in reality plants can even surpass that. Not only can they regenerate lost parts, but also the whole plant body can be reborn from a few existing cells. Despite the decades old realization that plant cells possess the ability to regenerate a complete shoot and root system, it is only now that the underlying mechanisms are being unraveled. De novo plant regeneration involves the initiation of regenerative mass, acquisition of the pluripotent state, reconstitution of stem cells and assembly of regulatory interactions. Recent studies have furthered our understanding on the making of a complete plant system in the absence of embryonic positional cues. We review the recent studies probing the molecular mechanisms of de novo plant regeneration in response to external inductive cues and our current knowledge of direct reprogramming of root to shoot and vice versa. We further discuss how de novo regeneration can be exploited to meet the demands of green culture industries and to serve as a general model to address the fundamental questions of regeneration across the plant kingdom.

Effects of gibberellin mutations on in vitro shoot bud regeneration of ...

African Journals Online (AJOL)

hormone in regulating plant growth and development. It is interesting to know the effects of gibberellin and its signalling pathway on plant regeneration. In this report Arabidopsis thaliana landsberg (wild type), ga1-3 (gibberellin biosynthesis deficiency mutant), gai (gibberellin insensitive mutant), penta mutant (lacking GA1, ...

Rapid Screening of In-Vitro Regenerated Plantlets of Four Nigerian ...

African Journals Online (AJOL)

Prof. Ogunji

Tissue culture technique provides a rapid means of studying plant-pathogen interaction in a controlled ... Keywords: cowpea, in-vitro regeneration, hormones, Fusarium wilt, protocols. .... solanacearum and evaluation of tomato in Nepal.

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.

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

2015-01-01

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. 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. PMID:25050479

Germination and In Vitro Regeneration Response of Local Nigerian ...

African Journals Online (AJOL)

Prof. Ogunji

the highest germination percentage of 57.33% and percentage contamination of. 11.11% ... development of in vitro regeneration of the crop from various explant sources. The advent of ..... Effect of variety and plant growth regulators on callus.

the role of plant growth regulators in morphogenesis

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A. Mujib

2018-01-01

Full Text Available Althaea officinalis L. (marshmallow belonging to the Malvaceae family, is an important plant that contains a variety of important phytocompounds including asparagine, pectin, flavonoids, polyphenolic acid, and scopoletin. The yield of these compounds can be improved using biotechnological methods that allow for a steady and continuous regeneration of plant material. To the best of our knowledge, thus far, the In vitro clonal multiplication of marshmallow has not been attempted on a large scale. Therefore, in this study, we developed callus induction and multiple shoot regeneration protocols from explants. All the explants, i.e., roots, nodes, and leaves, evoked compact white or yellow calli in a medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D, which grew vigorously. The callus induction frequency was the highest (62.1% from stem nodes, followed by leaves (39.1% and roots (27.5%. The differential behavior of explants in response to various plant growth regulators (PGRs was studied. The calli from leaves and roots were noted to be non-organogenic/embryogenic in media containing different PGR concentrations and have been described in this communication. The stem nodes used were cultured on MS media amended with different concentrations of benzyl-amino-purine (BAP: 0.5, 1.0, and 2.0 mg/l. Multiple shoots were formed at variable numbers, the maximum being in a medium supplemented with 1.0 mg/l of BAP. The induced shoots were rooted in IBA-, NAA-, and IAA-amended media, where IBA at 0.5 mg/l induced a maximum number of roots (8.8 roots/shoot. The regenerated plants were transferred to plastic pots, filled with soilrite and soil (1 : 1, and finally, transferred to outdoor conditions.

Cryogenic regenerators

International Nuclear Information System (INIS)

Kush, P.; Joshi, S.C.; Thirumaleshwar, M.

1986-01-01

Importance of regenerators in cryogenic refrigerators is highlighted. Design aspects of regenerator are reviewed and the factors involved in the selection of regenerator material are enumerated. Various methods used to calculate the heat transfer coefficient and regenerator effectiveness are mentioned. Variation of effectiveness with various parameters is calculated by a computer programme using the ideal, Ackermann and Tipler formulae. Results are presented in graphical form. Listing of the computer programme is given in the Appendix. (author)

Genotype dependent callus induction and shoot regeneration in ...

African Journals Online (AJOL)

This study aims to observe the effect of genotype, hormone and culture conditions on sunflower (Helianthus annuus L.) callus induction and indirect plant regeneration. Calli were obtained from hypocotyl and cotyledon explants of five different sunflower genotypes; Trakya 80, Trakya 129, Trakya 259, Trakya 2098 and ...

Regeneration and localization of radioactive waste in the nuclear fuel cycle

International Nuclear Information System (INIS)

Egorov, N.N.; Kudryavtsev, E.G.; Nikipelov, B.V.; Polyakov, A.S.; Zakharkin, B.S.; Mamaev, L.A.

1993-01-01

Normal functioning of the nuclear-power industry is only possible with a closed fuel cycle, including regeneration of the spent fuel from atomic power plants, the production and recycling of the secondary fuel, and localization of the radioactive waste. Despite the diversity of contemporary attitudes toward the structure of the nuclear fuel cycle around the world, the closure of the fuel cycle has been fundamental to the atomic-power industry in the USSR since the very beginning, and has taken on even greater significance in Russia today. From the beginning, the idea of a closed fuel cycle has been based essentially on one fundamental criterion: the concept of expanded productivity on the basis of fuel regeneration, i.e., the economic factor. Important as economic factors are, safety issues have taken on great significance in recent years: not only power-station reactors but all the ancillary stages of the fuel cycle must meet fundamentally new reliability, safety, and environmental hazards. The RT-1 plant is a versatile operation, regenerating spent fuel from VVER-440, BN-350, and BN-600 reactors, nuclear icebreakers and submarines, research reactors, and other power units. The plant can reprocess 400 ton/year of basic VVER-440 fuel. World-class modern processes have been introduced at the plant, meeting the necessary quality standards: zonal planning, remote operation to eliminate direct contact of the staff with radioactive material, extensive monitoring and control systems, multistage gas-purification systems, and new waste-treatment methods

Thidiazuron enhanced regeneration and silymarin content in silybum marianum

International Nuclear Information System (INIS)

Khan, M.A.; Abbasi, B.H.; Shinwari, Z.K.

2014-01-01

Silybum marianum, of family Asteraceae is renowned for production of biologically important silymarin, which has shown multi-dimensional medicinal properties. It has a high protective role against jaundice and hepatitis C worldwide. We hereby established a feasible and efficient method for indirect regeneration of S. marianum for production of consistent plantlets. Calli were induced from leaf explants of seed-derived plantlets on Murashige and Skoog (MS) medium supplemented with several concentrations of different plant growth regulators (PGRs). Highest callogenic response (89%) was recorded for 4.4 meu M Thidiazuron (TDZ) in combination with 6.6 meu M Kinetin (Kn). Subsequent sub-culturing of callus after 4 weeks of culture, on medium with similar compositions of PGRs induced shoot organogenesis. Highest shoot induction frequency (86%) with maximum mean multiple shoots (26 shoots per explant) were recorded for 11meu M TDZ after 4 weeks of transfer. Longest shoots (4.1 cm) were recorded for MS medium augmented with 6.6 meu M TDZ and 4.4 meu M naphthalene acetic acid (NAA). Furthermore, rooted plantlets were developed on MS medium containing different concentrations of indole acetic acid (IAA). Silymarin was determined by High performance liquid chromatography (HPLC) and 8.47 mg/g DW silymarin was detected in the regenerated plantlets. This study contributes to a better understanding of the different mechanisms involved in morphogenesis and production of biologically active principle in Silybum marianum. (author)

In vitro regeneration of a common medicinal plant, Ocimum sanctum ...

African Journals Online (AJOL)

Embracing micro-propagation method for large scale production of plantlets and also for protection of appropriate germplasm is a prerequisite that needs to be undertaken in order to develop a rapid in vitro regeneration protocol for Ocimum sanctum L. Shoot tips as well as nodal segments were subjected to numerous ...

Effect of plant spacing and weeding frequency on weed infestation ...

African Journals Online (AJOL)

Common bean is an important food and cash crop in eastern Ethiopia. However, its yield is constrained by weeds. Therefore, this study was conducted in 2012 main cropping season at Haramaya and Hirna research fields, eastern Ethiopia, to determine the effect of plant spacing and weeding frequency on weeds, yield ...

Tissue culture-induced genetic and epigenetic variation in triticale (× Triticosecale spp. Wittmack ex A. Camus 1927) regenerants.

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Machczyńska, Joanna; Zimny, Janusz; Bednarek, Piotr Tomasz

2015-10-01

Plant regeneration via in vitro culture can induce genetic and epigenetic variation; however, the extent of such changes in triticale is not yet understood. In the present study, metAFLP, a variation of methylation-sensitive amplified fragment length polymorphism analysis, was used to investigate tissue culture-induced variation in triticale regenerants derived from four distinct genotypes using androgenesis and somatic embryogenesis. The metAFLP technique enabled identification of both sequence and DNA methylation pattern changes in a single experiment. Moreover, it was possible to quantify subtle effects such as sequence variation, demethylation, and de novo methylation, which affected 19, 5.5, 4.5% of sites, respectively. Comparison of variation in different genotypes and with different in vitro regeneration approaches demonstrated that both the culture technique and genetic background of donor plants affected tissue culture-induced variation. The results showed that the metAFLP approach could be used for quantification of tissue culture-induced variation and provided direct evidence that in vitro plant regeneration could cause genetic and epigenetic variation.

Stable transformation via particle bombardment in two different soybean regeneration systems.

Science.gov (United States)

Sato, S; Newell, C; Kolacz, K; Tredo, L; Finer, J; Hinchee, M

1993-05-01

The Biolistics(®) particle delivery system for the transformation of soybean (Glycine max L. Merr.) was evaluated in two different regeneration systems. The first system was multiple shoot proliferation from shoot tips obtained from immature zygotic embryos of the cultivar Williams 82, and the second was somatic embryogenesis from a long term proliferative suspension culture of the cultivar Fayette. Bombardment of shoot tips with tungsten particles, coated with precipitated DNA containing the gene for β-glucuronidase (GUS), produced GUS-positive sectors in 30% of the regenerated shoots. However, none of the regenerants which developed into plants continued to produce GUS positive tissue. Bombardment of embryogenic suspension cultures produced GUS positive globular somatic embryos which proliferated into GUS positive somatic embryos and plants. An average of 4 independent transgenic lines were generated per bombarded flask of an embryogenic suspension. Particle bombardment delivered particles into the first two cell layers of either shoot tips or somatic embryos. Histological analysis indicated that shoot organogenesis appeared to involve more than the first two superficial cell layers of a shoot tip, while somatic embryo proliferation occurred from the first cell layer of existing somatic embryos. The different transformation results obtained with these two systems appeared to be directly related to differences in the cell types which were responsible for regeneration and their accessibility to particle penetration.

Isatin as an auxin source favoring floral and vegetative shoot regeneration from calli produced by thin layer explants of tomato pedicel

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Applewhite, P. B.; K-Sawhney, R.; Galston, A. W.

1994-01-01

Thin layer explants taken from the pedicels and peduncles of flowering tomato plants yielded calli with great organogenetic potential. Of the 15 cultivars tested, 7 regenerated roots, shoots and eventually entire fruit-bearing plants. Calli grown on modified Murashige-Skoog medium responded to varied auxins and cytokinins with different morphogenetic patterns. Thus, naphthaleneacetic acid yielded root-producing calli, while the auxin precursor isatin (indole 2,3-dione) caused the production of calli with vegetative and floral shoots, rarely yielding roots. This may be related to isatin's slow, steady conversion to an active auxin (Plant Physiol 41:1485-1488, 1966) in contrast with naphthaleneacetic acid's immediate presentation of a high level of active auxin. The highest incidence of vegetative shoot (100%) and flower (50%) formation was obtained with 10 micromoles isatin and 3 micromoles zeatin. A few of the flowers developed into ripe fruits. The high frequency of induction of vegetative shoots and flowers before roots with isatin suggests its utility in micropropagation from plant tissue cultures.

Grazing on Regeneration Sites Encourages Pine Seedling Growth

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Raymond D. Ratliff; Renee G. Denton

1995-01-01

Effects of season-long, deferred-rotation, and rest-rotation grazing, on ponderosa pine (Pinus ponderosa Dougl. ex Laws.) seedling growth and herbaceous vegetation control were studied in regeneration sites at Boyd Hill, Modoc National Forest, California. Seedlings were planted in 1989. Pine seedling survival and damage did not differ, but the...

De novo assembly of plant body plan: a step ahead of Deadpool

OpenAIRE

Kareem, Abdul; Radhakrishnan, Dhanya; Sondhi, Yash; Aiyaz, Mohammed; Roy, Merin V.; Sugimoto, Kaoru; Prasad, Kalika

2016-01-01

Abstract While in the movie Deadpool it is possible for a human to recreate an arm from scratch, in reality plants can even surpass that. Not only can they regenerate lost parts, but also the whole plant body can be reborn from a few existing cells. Despite the decades old realization that plant cells possess the ability to regenerate a complete?shoot and root system, it is only now that the underlying mechanisms are being unraveled. De novo plant regeneration involves the initiation of regen...

Ion Frequency Landscape in Growing Plants.

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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.

Improvement of embryogenesis and regeneration by air desiccation in maize (zea mays l.)

International Nuclear Information System (INIS)

Morshed, S.; Siddique, B.; Islam, S.M.S.

2016-01-01

Calli derived from mature embryos of four maize varieties viz. Mohar, Khoi bhutta, Barnali and Shuvra were cultured in three basal media for regeneration (MS, N6 and 6N1) which individually supplemented with four hormonal combinations e.g. H1 = BAP 0.5 mg/l + IAA 0.0 mg/l, H2 = BAP 1.0 mg/l + IAA 0.5 mg/l, H3 = BAP 1.5 mg/l + IAA 1.0 mg/l and H4 = BAP 2.0 mg/l + IAA 1.5 mg/l. The highest frequency of regeneration was found with MS + H2 (41.35%) in Mohar, while the lowest was 17.37% in 6N1 + H1 for Barnali. To enhance the capability of regeneration, calli were pretreated by ten groups (6, 12, 18, 24, 30, 36, 42, 48, 54 and 60 h) of desiccation periods. The degrees of desiccation of pretreated calli were determined; and it was ranged as 6.23 to 40.52% where Khoi bhutta showed the maximum value at 60 h desiccation. The callus of Mohar exhibited the highest frequency of regeneration (75.24%) which desiccated for 48 h; and it was around 2 fold higher than the control. The variety Khoi bhutta showed the lowest efficiency (31.80%) when the callus was desiccated for 6 h. All the varieties performed their maximum regeneration at different periods, where 36, 30 and 42 h desiccation were optimal for Barnali (67.23%), Khoi bhutta (68.03%) and Shuvra (73.98%) accordingly. Analysis of variance (ANOVA) showed significant effect of maize genotype and periods of partial air desiccation to enhance regeneration at p<0.05 level. (author)

Study of regeneration system of 300 MW power unit based on nondeaerating heat balance diagram at reduced load

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Esin, S. B.; Trifonov, N. N.; Sukhorukov, Yu. G.; Yurchenko, A. Yu.; Grigor'eva, E. B.; Snegin, I. P.; Zhivykh, D. A.; Medvedkin, A. V.; Ryabich, V. A.

2015-09-01

More than 30 power units of thermal power stations, based on the nondeaerating heat balance diagram, successfully operate in the former Soviet Union. Most of them are power units with a power of 300 MW, equipped with HTGZ and LMZ turbines. They operate according to a variable electric load curve characterized by deep reductions when undergoing night minimums. Additional extension of the range of power unit adjustment makes it possible to maintain the dispatch load curve and obtain profit for the electric power plant. The objective of this research is to carry out estimated and experimental processing of the operating regimes of the regeneration system of steam-turbine plants within the extended adjustment range and under the conditions when the constraints on the regeneration system and its equipment are removed. Constraints concerning the heat balance diagram that reduce the power unit efficiency when extending the adjustment range have been considered. Test results are presented for the nondeaerating heat balance diagram with the HTGZ turbine. Turbine pump and feed electric pump operation was studied at a power unit load of 120-300 MW. The reliability of feed pump operation is confirmed by a stable vibratory condition and the absence of cavitation noise and vibration at a frequency that characterizes the cavitation condition, as well as by oil temperature maintenance after bearings within normal limits. Cavitation performance of pumps in the studied range of their operation has been determined. Technical solutions are proposed on providing a profitable and stable operation of regeneration systems when extending the range of adjustment of power unit load. A nondeaerating diagram of high-pressure preheater (HPP) condensate discharge to the mixer. A regeneration system has been developed and studied on the operating power unit fitted with a deaeratorless thermal circuit of the system for removing the high-pressure preheater heating steam condensate to the mixer

Regeneration systems for pyramiding disease resistance into walnut rootstocks

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This study was conducted to regenerate selected walnut rootstocks adventitiously. This is an essential step to be able to produce transgenic walnut rootstocks with superior traits, such as disease resistance. A series of plant tissue culture experiments were conducted on RX1 and VX211 rootstocks wit...

The cancer paradigms of mammalian regeneration: can mammals regenerate as amphibians?

Science.gov (United States)

Sarig, Rachel; Tzahor, Eldad

2017-04-01

Regeneration in mammals is restricted to distinct tissues and occurs mainly by expansion and maturation of resident stem cells. During regeneration, even subtle mutations in the proliferating cells may cause a detrimental effect by eliciting abnormal differentiation or malignant transformation. Indeed, cancer in mammals has been shown to arise through deregulation of stem cells maturation, which often leads to a differentiation block and cell transformation. In contrast, lower organisms such as amphibians retain a remarkable regenerative capacity in various organs, which occurs via de- and re-differentiation of mature cells. Interestingly, regenerating amphibian cells are highly resistant to oncogenic transformation. Therapeutic approaches to improve mammalian regeneration mainly include stem-cell transplantations; but, these have proved unsuccessful in non-regenerating organs such as the heart. A recently developed approach is to induce de-differentiation of mature cardiomyocytes using factors that trigger their re-entry into the cell cycle. This novel approach raises numerous questions regarding the balance between transformation and regeneration induced by de-differentiation of mature mammalian somatic cells. Can this balance be controlled artificially? Do de-differentiated cells acquire the protection mechanisms seen in regenerating cells of lower organisms? Is this model unique to the cardiac tissue, which rarely develops tumors? This review describes regeneration processes in both mammals and lower organisms and, particularly, the ability of regenerating cells to avoid transformation. By comparing the characteristics of mammalian embryonic and somatic cells, we discuss therapeutic strategies of using various cell populations for regeneration. Finally, we describe a novel cardiac regeneration approach and its implications for regenerative medicine. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email

Comparison of regeneration potentials in tissue cultures of primitive and cultivated tomato species (Lycopersicon sp.

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M. Lech

2014-01-01

Full Text Available Regeneration capacities of two tomato cultivars: Potentat and Rutgers, and of three accessions of wild tomato species: Lycopersicon peruvianum PI 128650, L. peruvianum var. dentatum PI 128655 and L. glandulosum were studied using an universal medium suitable for regeneration of those plants from leaf pieces in tissue culture. Fragments of leaf blades were taken from plants raised in greenhouse conditions and placed on a modified MS medium containing 0.3 mg/l IAA and 3.0 mg/l BAP solidified with 1% agar. The explants were transferred every 4-5 weeks on fresh medium of the same composition. It was shown that all the three primitive tomato species revealed much higher multiplication coefficients than the two cultivars. Appropriate values were: 11 - for L. glandulosum, 8 - for L. peruvianum, 7 - for L. peruvianum var. dentatum, 4 - for L. esculentum cv. Potentat and 2 - cv. Rutgers. Completely regenerated plants were obtained from all the tested species, but organogenesis occurred almost two weeks earlier in wild tomatoes than in the culitivated varieties of L. esculentum.

In vitro plant regeneration from leaf explants of Solanum pimpinellifolium L.

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Shirley Valderrama-Alfaro

2011-01-01

Full Text Available Tomato is a species of agricultural importance. Besides, it is a source of vitamins, minerals and antioxidant compounds. Therefore it is essential to obtain varieties resistant to diseases. Solanum pimpinellifolium L. ‘Tomatillo wild’, one of the wild relatives of tomato, is considered multipurpose reservoir of genes. This characteristic must be exploited. In vitro plantlets from leaves of ‘wild tomatillo’ were regenerated with this objective. A system for in vitro germination of seeds obtained from ex vitro sources was created. The use of seed allowed obtaining adequate seedlings in a short time to start regeneration. Thein vitro response of explants was evaluated in four treatments. The Murashige and Skoog (MS basal culture medium supplemented with a-naphthaleneacetic acid (NAA and 6-benzyl aminopurine (BAP was used in different combinations. The higher percentage (30% of shoot induction was achieved with 0.1 mg l1 NAA / 1 mg l1 BAP. The presence of callus and roots was observed after seven days of culture in the combination treatment with 1 mg l1 NAA / 0.1 mg l1 BAP. Callus showed 1 or 2 adventitious shoots per explant after 30 days of culture and 3 to 6 shoots after seventy days. Furthermore, the presence of fully formed adventitious plantlets (shoot and root was observed after the fifth week of culture. Therefore, the best combination for in vitro regeneration is NAA 0.1 mg l1 / 1 mg l1 BAP. Keywords: auxin, cytokinins, indirect organogenesis

Transformation of medicinal plants using Agrobacterium tumefaciens

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Katarzyna Bandurska

2016-12-01

Full Text Available For many years attempts are made to develop efficient methods for transformation of medicinal plants via Agrobacterium tumefaciens. It is a soil bacteria which possess a natural ability to infect plants in places of injures which results in arise of cancerous growths (crown gall. This is possible thanks a transfer of fragment of Ti plasmid into plant cells and stable integration with a plant genome. Efficiency of medicinal plant transformation depends on many factors for example: Agrobacterium strain, methods and procedures of transformation as well as on plant species, type and age of the explants and regeneration conditions. The main goal of plant transformation is to increase the amount of naturally occurring bioactive compounds and the production of biopharmaceuticals. Genetic plant transformation via bacteria of the genus Agrobacterium is a complex process which requires detailed analysis of incorporated transgene expression and occurs only in the case when the plant cell acquires the ability to regenerate. In many cases, the regeneration efficiency observed in medicinal plants are inefficient after applied transformation procedures. To date there have been attempts of genetic transformation by using A. tumefaciens of medicinal plants belonging to the families: Apocynaceae, Araceae, Araliaceae, Asphodelaceae, Asteraceae, Begoniaceae, Crassulaceae, Fabaceae, Lamiaceae, Linaceae, Papaveraceae, Plantaginaceae, Scrophulariaceae and Solanaceae.

Transformation of medicinal plants using Agrobacterium tumefaciens.

Science.gov (United States)

Bandurska, Katarzyna; Berdowska, Agnieszka; Król, Małgorzata

2016-12-20

For many years attempts are made to develop efficient methods for transformation of medicinal plants via Agrobacterium tumefaciens. It is a soil bacteria which possess a natural ability to infect plants in places of injures which results in arise of cancerous growths (crown gall). This is possible thanks a transfer of fragment of Ti plasmid into plant cells and stable integration with a plant genome. Efficiency of medicinal plant transformation depends on many factors for example: Agrobacterium strain, methods and procedures of transformation as well as on plant species, type and age of the explants and regeneration conditions. The main goal of plant transformation is to increase the amount of naturally occurring bioactive compounds and the production of biopharmaceuticals. Genetic plant transformation via bacteria of the genus Agrobacterium is a complex process which requires detailed analysis of incorporated transgene expression and occurs only in the case when the plant cell acquires the ability to regenerate. In many cases, the regeneration efficiency observed in medicinal plants are inefficient after applied transformation procedures. To date there have been attempts of genetic transformation by using A. tumefaciens of medicinal plants belonging to the families: Apocynaceae, Araceae, Araliaceae, Asphodelaceae, Asteraceae, Begoniaceae, Crassulaceae, Fabaceae, Lamiaceae, Linaceae, Papaveraceae, Plantaginaceae, Scrophulariaceae and Solanaceae.

ADVANCING PROTOCOLS FOR POPLARS in vitro PROPAGATION, REGENERATION AND SELECTION OF TRANSFORMANTS

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Nataliia Kutsokon

2013-02-01

Full Text Available Poplars (genus Populus have emerged as a model organism for forest biotechnology, and genetic modification is more advanced for this genus than for any other tree. So far several protocols for microclonal propagation and regeneration for Populus species have been developed. However it is well known that these protocols differ for various species and need to be adapted even for different clones of the same species. This work was focused on developing of protocols for propagation, regeneration and putative transformant´s selection of aspen Populus tremula L. and other two fast-growing Populus species (P. nigra L., P. x canadensis Moench. The regeneration ability for black poplar explants was demonstrated to be three times higher compared to those for aspen and hybrid poplar. It was found that concentration 1 mg/L of phosphinothricin and 25 mg/L of kanamycin is toxic for non- transgenic plant tissues of P. x canadensis and can be applied in transformation experiments when genes of resistance to the corresponding selective agents into the plant genome are introduced.

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

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...

Regeneration and molecular analysis of date palm ( Phoenix ...

African Journals Online (AJOL)

Clonal plants of date palm (Poenix dactylifera L.) were regenerated from juvenile leaves on regimes consisting of the use of 2,4-D. Success depended on the concentrations of 2,4-D tested. The cultures produced adventitious shoot buds directly at the basal part of leaves as well as excessive calli. Somaclonal variation in ...

Micropropagation and validation of genetic and biochemical fidelity among regenerants of Nothapodytes nimmoniana (Graham) Mabb. employing ISSR markers and HPLC.

Science.gov (United States)

Prakash, Lokesh; Middha, Sushil Kumar; Mohanty, Sudipta Kumar; Swamy, Mallappa Kumara

2016-12-01

An in vitro protocol has been established for clonal propagation of Nothapodytes nimmoniana which is an important source of Camptothecin (CPT). Elite source was identified based on the chemical potency to accumulate the optimum level of CPT. Different types and concentrations of plant growth regulators were used to study their effect on inducing multiple shoots from the explants regenerated from embryos of N. nimmoniana. Of these, a combination of N6-benzyladenine (0.2 mg L -1 ) and Indole-3-butyric acid (IBA) (0.1 mg L -1 ) proved optimum for differentiating multiple shoots in 90.6 % of the cultures with an average of 10.24 shoots per explant obtained within 8 weeks of inoculation. Nearly, 92 % of the excised in vitro shoots rooted on half strength Murashige and Skoog (MS) medium containing 0.05 % activated charcoal, supplemented with 1-naphthaleneacetic acid and IBA at 0.1 mg L -1 each. The micropropagated plants were evaluated for their genetic fidelity by employing inter simple sequence repeats (ISSR) markers. Ten individuals, randomly chosen from a population of 145 regenerants, were compared with the donor plant. The regenerated plants were also evaluated for their chemical potency using high-performance liquid chromatography (HPLC) analysis of CPT content. The true-to-type nature of the micropropagated plants was confirmed based on their monomorphic banding profiles with that of the mother plants using ISSR markers. Besides, HPLC evaluation of the CPT content confirmed the existence of chemical uniformity among the regenerated plants and the elite mother plant.

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.

Regenerable Photovoltaic Devices with a Hydrogel-Embedded Microvascular Network

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Koo, Hyung-Jun; Velev, Orlin D.

2013-01-01

Light-driven degradation of photoactive molecules could be one of the major obstacles to stable long term operation of organic dye-based solar light harvesting devices. One solution to this problem may be mimicking the regeneration functionality of a plant leaf. We report an organic dye photovoltaic system that has been endowed with such microfluidic regeneration functionality. A hydrogel medium with embedded channels allows rapid and uniform supply of photoactive reagents by a convection-diffusion mechanism. A washing-activation cycle enables reliable replacement of the organic component in a dye-sensitized photovoltaic system. Repetitive restoration of photovoltaic performance after intensive device degradation is demonstrated. PMID:23912814

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...... control strategies are effective means for providing ancillary frequency control of variable speed wind turbines with full-scale back-to-back power converters....... emulation, primary frequency control and secondary frequency control, are proposed in order to improve the frequency stability of power systems. The modified IEEE 39-bus test system with a large-scale wind power penetration is chosen as the studied power system. Simulation results show that the proposed...

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.

Abiotic stress leads to somatic and heritable changes in homologous recombination frequency, point mutation frequency and microsatellite stability in Arabidopsis plants

International Nuclear Information System (INIS)

Yao Youli; Kovalchuk, Igor

2011-01-01

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.

Regeneration

Science.gov (United States)

George A. Schier; Wayne D. Shepperd; John R. Jones

1985-01-01

There are basically two approaches to regenerating aspen stands-sexual reproduction using seed, or vegetative regeneration by root suckering. In the West, root suckering is the most practical method. The advantage of having an existing, well established root system capable of producing numerous root suckers easily outweighs natural or artificial reforestation in the...

Large-Scale Regeneration Patterns of Pinus nigra Subsp. salzmannii: Poor Evidence of Increasing Facilitation Across a Drought Gradient

Directory of Open Access Journals (Sweden)

Pedro Antonio Tíscar

2013-12-01

Full Text Available Tree recruitment is a key process underlying stand dynamics and sustainability in managed forests. Woody plant cover is known to affect the regeneration success of Pinus nigra, suggesting the existence of facilitative plant-plant interactions. The regeneration patterns of this Mediterranean pine were analyzed across its distribution area, using data from 3226 plots of the Spanish National Forest Inventory. We aimed to test the hypothesis that seedlings establishment occurs under higher values of either canopy or shrub cover in the driest populations, as predicted by the stress-gradient hypothesis. Data were analyzed by means of Generalized Linear Models and multivariate methods. Results revealed that regeneration failure occurs on a regional scale, and that regeneration is facilitated by tree canopy cover of 55%–80%. A non-linear pattern of interaction along an aridity gradient was identified, with competition at the wettest site, high facilitation at the mid-dry sites, and low facilitation at the driest site. Evidence suggests that some shrub species may facilitate recruitment in the harsher areas. Collectively, our results reduce the possibilities of adapting forest management to drying climates by the application of alternative silvicultural prescriptions involving canopy cover.

Limited native plant regeneration in novel, exotic-dominated forests on Hawaii

Science.gov (United States)

Joseph Mascaro; Kristen K. Becklund; R. Flint Hughes; Stefan A. Schnitzer

2008-01-01

Ecological invasions are amajor driver of global environmental change. When invasions are frequent and prolonged, exotic species can become dominant and ultimately create novel ecosystem types. These ecosystems are now widespread globally. Recent evidence from Puerto Rico suggests that exoticdominated forests can provide suitable regeneration sites for native species...

In-vitro regeneration of sugarcane (saccharum officinarum L.)

International Nuclear Information System (INIS)

Azu, E.

2009-01-01

Sugarcane (Saccharum officinarum L.) cultivars Barbados 46 (B46), Natal Coimbatore 339 (NC0339), Ragna, local sugarcane cultivar (LSC) and Kenana (Kn) series sourced from Kyebi, Akorley, Subriso, Jejeti and the University of Ghana Agriculture Research Station, Kpong, were evaluated for sterilisation, multiplication and rooting. An efficient double sterilisation protocol was achieved by immersing axillary buds pre-treated with Goldazim (active ingredient carbendazim) in 0.2% mercuric chloride for 7 minutes followed by 0.1 % mercuric chloride for 3 minutes. At this optimal sterilisation regime, 70% of the cultured buds were decontaminated. However, post sterilisation survival required the incorporation of 0.002g/L and 0.001g/L of amphotericin Band cefotaxime respectively in the culture medium indicating that the contaminants were endophytic. Evaluation for multiple shoot induction was conducted using Murashige and Skoog (1962) basal salts (MS) medium supplemented with 25g/L sucrose, 2mg/L IAA, 2mg/L GA 3 , 3g/L activated charcoal and varying concentrations (mg/L) of BAP or kinetin. The response of the cultivars to shoot induction varied with Ragna producing the highest number of shoots (2.17) on 5mg/L BAP indicating genotypic differences. Naphthalene acetic acid (NAA) at a concentration of 5mg/L induced the highest frequency (65%) of roots in all the cultivars tested. Post-flask acclimatization and survival of plantlets was high and independent of the age at which regenerated plantlets were transferred to the plant barn for weaning. This procedure could therefore be useful for regenerating sugarcane plantlets as well as provide target tissues for genetic transformation studies (au).

Climate change will restrict ponderosa pine forest regeneration in the 21st century in absence of disturbance

Science.gov (United States)

Petrie, M. D.; Bradford, J. B.; Hubbard, R. M.; Lauenroth, W. K.; Andrews, C.

2016-12-01

The persistence of ponderosa pine forests and the ability for these forests to colonize new habitats in the 21st century will be influenced by how climate change supports ponderosa pine regeneration through the demographic processes of seed production, germination and survival. Yet, the way that climate change may support or restrict the frequency of successful regeneration is unclear. We developed a quantitative, criteria-based framework to estimate ponderosa pine regeneration potential (RP: a metric from 0-1) in response to climate forcings and environmental conditions. We used the SOILWAT ecosystem water balance model to simulate drivers of air and soil temperature, evaporation and soil moisture availability for 47 ponderosa pine sites across the western United States, using meteorological data from 1910-2014, and projections from nine General Circulation Models and the RCP 8.5 emissions scenario for 2020-2099. Climate change simulations increased the success of early developmental stages of seed production and germination, and supported 49.7% higher RP in 2020-2059 compared to averages from 1910-2014. As temperatures increased in 2060-2099, survival scores decreased, and RP was reduced by 50.3% compared to 1910-2014. Although the frequency of years with high RP did not change in 2060-2099 (12% of years), the frequency of years with very low RP increased from 25% to 58% of years. Thus, climate change will initially support higher RP and more favorable years in 2020-2059, yet will reduce average RP and the frequency of years with moderate regeneration support in 2060-2099. Forest regeneration is complex and not fully-understood, but our results suggest it is likely that climate change alone will instigate restrictions to the persistence and expansion of ponderosa pine in the 21st century.

Efficient in vitro regeneration protocol of Centella asiatica (L.) Urban ...

African Journals Online (AJOL)

The present communication reports an efficient in vitro plantlet regeneration protocol for endemic umbellifer Centella asiatica (L.) urban via callus mediated organogenesis from leaf and stem explants. The plant is pharmacologically very important and its consumption as underutilized green leafy vegetable affluent in ...

Damping of Low Frequency Power System Oscillations with Wind Power Plants

DEFF Research Database (Denmark)

Adamczyk, Andrzej Grzegorz

of wind power plants on power system low frequency oscillations and identify methods and limitations for potential contribution to the damping of such oscillations. Consequently, the first part of the studies focuses on how the increased penetration of wind power into power systems affects their natural...... oscillatory performance. To do so, at first a generic test grid displaying a complex inter-area oscillation pattern is introduced. After the evaluation of the test grid oscillatory profile for various wind power penetration scenarios, it is concluded that full-converter based wind power plant dynamics do......-synchronous power source. The main body of the work is devoted to the damping control design for wind power plants with focus on the impact of such control on the plant operation. It can be expected that the referred impact is directly proportional to the control effort, which for power processing devices should...

A simulation study of harmonics regeneration in noise reduction for electric and acoustic stimulation.

Science.gov (United States)

Hu, Yi

2010-05-01

Recent research results show that combined electric and acoustic stimulation (EAS) significantly improves speech recognition in noise, and it is generally established that access to the improved F0 representation of target speech, along with the glimpse cues, provide the EAS benefits. Under noisy listening conditions, noise signals degrade these important cues by introducing undesired temporal-frequency components and corrupting harmonics structure. In this study, the potential of combining noise reduction and harmonics regeneration techniques was investigated to further improve speech intelligibility in noise by providing improved beneficial cues for EAS. Three hypotheses were tested: (1) noise reduction methods can improve speech intelligibility in noise for EAS; (2) harmonics regeneration after noise reduction can further improve speech intelligibility in noise for EAS; and (3) harmonics sideband constraints in frequency domain (or equivalently, amplitude modulation in temporal domain), even deterministic ones, can provide additional benefits. Test results demonstrate that combining noise reduction and harmonics regeneration can significantly improve speech recognition in noise for EAS, and it is also beneficial to preserve the harmonics sidebands under adverse listening conditions. This finding warrants further work into the development of algorithms that regenerate harmonics and the related sidebands for EAS processing under noisy conditions.

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.

Desulfurization sorbent regeneration

Science.gov (United States)

Jalan, V.M.; Frost, D.G.

1982-07-07

A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

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...

Regeneration performance of CO2-rich solvents by using membrane vacuum regeneration technology: Relationships between absorbent structure and regeneration efficiency

International Nuclear Information System (INIS)

Yan, Shuiping; Fang, Mengxiang; Wang, Zhen; Luo, Zhongyang

2012-01-01

Highlights: ► MVR may be viable to successfully use less valuable heat to replace high grade steam. ► Increasing OH and amine groups will increase the regeneration efficiency. ► Absorbents with a four carbon chain length will be more attractive to MVR. ► Amino acid salts will be more appropriate for MVR. ► HRM conducted at ambient pressure and low temperature is inferior to MVR. -- Abstract: In order to give a better understanding for the selection of suitable absorbents for the novel membrane vacuum regeneration technology (MVR) which has the potential to reduce CO 2 energy requirement by utilizing the waste heat or low-grade energy, an experimental study to determine the relationships between chemical structure and vacuum regeneration behavior of CO 2 absorbents at 70 °C and 10 kPa was performed. Eleven typical absorbents with different functional groups in their chemical structures were investigated in terms of vacuum regeneration efficiencies. Results showed that the regeneration efficiency decreased with an increase of number of activated hydrogen atom in amine group and decreased with the number of hydroxyl group. Especially, more attention should be paid to these alkanolamines with one hydrogen atom in amine group and two or more hydroxyl groups in the structures due to their better comprehensive performance in regeneration, absorbent loss and CO 2 absorption aspects. Increasing the carbon chain length and amine groups in the absorbent structure contributed to the improvement of regeneration performance and reduction of absorbent volatile loss. These absorbents with a four carbon chain length bonded at amine group might be more attractive to MVR. Furthermore, polyamines were superior to monoamines in terms of higher regeneration efficiencies and lower absorbent losses. Additionally, the individual effects of the potassium carboxylate group and hydroxymethylene group were also compared in this study. Results showed that amino acid salts were more

Regeneration and vegetative propagation of Sphagnum palustre as factor of population stability

Directory of Open Access Journals (Sweden)

Dygna Sobotka

2015-01-01

Full Text Available The stability of the Sphagnum palustre populations on the meadows of the Kampinos National Park situated north-west of Warsaw was investigated in the period 1971-1974. Laboratory cultures were also started to establish the regenerative ability of various gametophyte parts of Sphagnum: the main stem, branches, leaves and spore germination. The green stems and apical branches of the plants showed the highest regeneration ability. Brown stems and white branches developed less intensively. Leaves showed no tendency to develop into new plants. Gametophores were found to form quicker and more effectively by way of regeneration than from spores. In natural conditions more intensive growth of branchings (new shoots from the apical and green parts of Sphagnum was also observed, whereas the brown parts did not exhibit this ability.

Studies in tissue culture of some indigenous rice (Oryza glaberrima Steud.) accessions in Ghana

International Nuclear Information System (INIS)

Diawuoh, R.G.

2011-01-01

A study was conducted with the aim of developing separate protocols for callus induction and plant regeneration from different parts of three O. glaberrima accessions indigenous to Ghana. The three O. glaberrima accessions, Guame, N/4 and SARI 1 were assessed for their callus induction and plant regeneration ability from leaf segments, mature dehusked seeds and anthers on different concentrations of plant growth regulators, incorporated into Murashige and Skoog, (1962) (MS) basal medium. For leaf segments, callus was induced on MS supplemented with (0-10) mg/l 2,4-D. Callus induction frequency was significantly (p≤0.05) different among accessions, as well as among the 2,4-dichlorophenoxyacetic acid (2,4-D) levels tested. Highest callus induction frequency was exhibited at a concentration of 6 mg/l 2,4-D for all accessions tested. Callus obtained was sub-cultured on regeneration medium consisting of MS supplemented with (1:0-5) mg.l NAA:BAP. Plant regeneration was nil. Instead, prolific root formation was observed. For mature dehusked seeds, callus induction medium consisted of MS supplemented with (0-6) mg/l 2,4-D. All tested accessions exhibited highest callus frequency at 4 mg/l 2,4-D. Similarly callus induction frequency was significantly (p≤0.05) different among accessions, as well as among concentrations of 2,4-D tested. Calli obtained were sub-cultured on MS medium supplemented with (0-2.5) mg/l 6-benzylaminopurine (BAP) and exhibited the highest regeneration frequency on medium containing 2.0 mg/l BAP. However, callus induced on a concentration of 3 mg/l 2,4-D and sub-cultured on a concentration of 2 mg/l BAP gave the best response n terms of shoot proliferation, growth and root development and therefore were considered to be the optimum concentrations for callus induction and plant regeneration respectively. Plantlet regeneration was achieved only in accession N/4 while Guame and SARI 1 exhibited poor regeneration response. Among the three rice

IN VITRO REGENERATION OF LOURO-PARDO (Cordia trichotoma (Vellozo Arrabida ex Steudel

Directory of Open Access Journals (Sweden)

Nilton César Mantovani

2010-08-01

Full Text Available This study was carried out aiming at evaluating the in vitro regeneration of louro-pardo (Cordia trichotoma (Vellozo Arrabida ex Steudel. Nodal segments were desinfested and innoculated in two basal media: WPM (Wood Plant Médium, 1981 and MS (Murashige & Skoog, 1962 supplemented with BAP (6-Benzylaminopurine, TDZ (Thidiazuron, NAA (Naphthaleneacetic Acid, GA3 (Gibberellic Acid, IBA (Indole-3-Butyric Acid and  A.C. (Activated Charcoal in different combinations and concentrations for each developmental step. The regeneration rate and the shoot elongation were higher in the WPM medium containing 0,1 mg.l-1 of BAP and GA3. The rooting of regenerated shoots was observed in IBA (0,5 mg.l-1 and Ativated Charcoal (1,5 g.l-1.

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

Evaluation of the tolerance to Finale® in the germination and regeneration of Cuban rice varieties (IACuba-17 and IACuba-19

Directory of Open Access Journals (Sweden)

Daymí Abreu

2005-01-01

Full Text Available Selection agent used during the shoot selection has an important role on the transgenic plant generation efficiency. In this work, the tolerance to the herbicide Finale® in two Cuban rice cultivars, IACuba17 and IACuba-19 was evaluated, and determined that 10 days exposure to 5 and 10 mg.l-1 of Finale® were enough to avoid seedlings of IAC-17 and IAC-19, respectively. Cultivated calluses (0, 2, 4 and 6 days in the absence of Finale®in the regeneration medium were used to evaluate the minimal concentration of Finale®that totally inhibits shoot regeneration. Pre-induced calluses cultured during two days and 3 mg.l-1 of Finale® in the regeneration medium was the most efficient combination to select shoots during the generation of transgenic plants resistant to the herbicide. Our shoot selection procedure reduces to 3 weeks the time to obtain shoots during the generation of transgenic rice plants. Key words: germination, mature seeds, Oryza, phosphinothricin, regeneration, selection markers

Micropropagation of nucellar embryos and their histological comparative study for regeneration ability with other explants of kinnow mandarin (Citrus reticulata Blanco)

International Nuclear Information System (INIS)

Kazmi, S.K.; Khan, S.; Kabir, N.

2018-01-01

Polyembryony is the most beneficial and distinct character in citrus seeds. This characteristic can be beneficial in citrus improvement programs. Nucellar embryos developed from nucellar wall in citrus seeds along with zygotic embryo are found to have high plants regeneration ability in comparison to zygotic embryos. Under In vitro culture conditions, nucellar embryos were detected and multiplied on MT media with 0.5ml of coconut water along with 50g/L sucrose. These nucellar embryonic tissues were also regenerated on MT media upplemented with 0.5 mg/L BAP and 0.5 mg/L kinetin. Many shoots were regenerated from nucellar embryonic tissue; these shoots were rooted on MT media supplemented with IBA 0.5mg/L and NAA 0.1 mg/L in addition to activated charcoal 0.5gm/L. The resulting plantlets were acclimatized in the green house. After micropropagation, histological studies of nucellar embryonic tissues were carried out under fluorescence microscope to examine their high regeneration ability in comparison with usual plant parts, like seeds, shoots as well as with tissue culture stages including embryogenic and non-embryogenic callus. It was found that nucellar embryos have more regeneration ability as compared to usual plant parts and other tissue culture stages. (author)

Complement components of nerve regeneration conditioned fluid influence the microenvironment of nerve regeneration

Directory of Open Access Journals (Sweden)

Guang-shuai Li

2016-01-01

Full Text Available Nerve regeneration conditioned fluid is secreted by nerve stumps inside a nerve regeneration chamber. A better understanding of the proteinogram of nerve regeneration conditioned fluid can provide evidence for studying the role of the microenvironment in peripheral nerve regeneration. In this study, we used cylindrical silicone tubes as the nerve regeneration chamber model for the repair of injured rat sciatic nerve. Isobaric tags for relative and absolute quantitation proteomics technology and western blot analysis confirmed that there were more than 10 complement components (complement factor I, C1q-A, C1q-B, C2, C3, C4, C5, C7, C8ß and complement factor D in the nerve regeneration conditioned fluid and each varied at different time points. These findings suggest that all these complement components have a functional role in nerve regeneration.

Efficient regeneration of sorghum, Sorghum bicolor (L.) Moench, from shoot-tip explant.

Science.gov (United States)

Syamala, D; Devi, Prathibha

2003-12-01

Novel protocols for production of multiple shoot-tip clumps and somatic embryos of Sorghum bicolor (L.) Moench were developed with long-term goal of crop improvement through genetic transformation. Multiple shoot-tip clumps were developed in vitro from shoot-tip explant of one-week old seedling, cultured on MS medium containing only BA (0.5, 1 or 2 mg/l) or both BA (1 or 2 mg/l) and 2,4-D (0.5 mg/l) with bi-weekly subculture. Somatic embryos were directly produced on the enlarged dome shaped growing structures that developed from the shoot-tips of one-week old seedling explants (without any callus formation) when cultured on MS medium supplemented with both 2,4-D (0.5 mg/l) and BA (0.5 mg/l). However, the supplementation of MS medium with only 2,4-D (0.5 mg/l) induced compact callus without any plantlet regeneration. Each multiple shoot-clump was capable of regenerating more than 80 shoots via an intensive differentiation of both axillary and adventitious shoot buds, the somatic embryos were capable of 90% germination, plant conversion and regeneration. The regenerated shoots could be efficiently rooted on MS medium containing indole-3-butyric acid (IBA 1 mg/l). The plants were successfully transplanted to glasshouse and grown to maturity with a survival rate of 98%. Morphogenetic response of the explants was found to be genotypically independent.

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.

Experimental mutagenesis in plants

International Nuclear Information System (INIS)

Conger, B.V.

1979-01-01

Considerable progress has been made in directed or controlled mutagenesis with bacterial systems, the genetic resolving power of which is much greater than that of higher plants. The mutagen specificity in higher plants has been of great interest, and numerous results and observations have been reported. The advances in the culture of plant cells and tissues have created much interest concerning the possibility of inducing and recovering mutants at the cellular level. There are great problems including the failure to regenerate plants from cells in all but a few species. The genetic and cytogenetic instability in the culture of plant tissues is well known, and the most common nuclear change is polyploidy including aneuploidy. The degree of polyploidy increases with calluses or culture age. In rice, the frequency of aneuploidy is greater in the calluses derived from roots than those derived from stem internodes. Polyploid and/or self-incompatible plant species are not as amenable to conventional mutation breeding techniques as diploid, self-fertilizing species. Inducing mutations in somatic tissues creates the problem of chimeras. However, the new cultivars of highly heterozygous, outcrossing, self-incompatible species are produced by combining several different clones. The performance of the progeny of at least 4 generations removed from the polycross of the parent clones is the important factor, and a high amount of heterozygocity is tolerated within cultivars and even on the same plants. (Yamashita, S.)

Regeneration of plantlets under NaCl stress from NaN3 treated ...

African Journals Online (AJOL)

use

2011-11-16

Nov 16, 2011 ... plant regeneration under NaCl stressed conditions was assessed in some sugarcane ( ... cell is a useful work for the establishment of pure form of ... balance. The relative water contents (RWC) were calculated .... J. Life Sci.

Liver regeneration

NARCIS (Netherlands)

Chamuleau, R. A.; Bosman, D. K.

1988-01-01

Despite great advances in analysing hemodynamic, morphological and biochemical changes during the process of liver regeneration, the exact (patho)physiological mechanism is still unknown. A short survey of literature is given of the kinetics of liver regeneration and the significance of different

Ecological restoration success is higher for natural regeneration than for active restoration in tropical forests

OpenAIRE

Crouzeilles, Renato; Ferreira, Mariana S.; Chazdon, Robin L.; Lindenmayer, David B.; Sansevero, Jerônimo B. B.; Monteiro, Lara; Iribarrem, Alvaro; Latawiec, Agnieszka E.; Strassburg, Bernardo B. N.

2017-01-01

Is active restoration the best approach to achieve ecological restoration success (the return to a reference condition, that is, old-growth forest) when compared to natural regeneration in tropical forests? Our meta-analysis of 133 studies demonstrated that natural regeneration surpasses active restoration in achieving tropical forest restoration success for all three biodiversity groups (plants, birds, and invertebrates) and five measures of vegetation structure (cover, density, litter, biom...

To the choice of the regeneration system of the K-1000-68/1500 turbine plant for the NPP with a vertical-type steam generator

International Nuclear Information System (INIS)

Kuznetsov, N.M.; Piskarev, A.A.; Grinman, M.I.; Kruglikov, P.A.

1985-01-01

Several variants of the heat regeneration system for the NPP with WWER-1000 type reactors using vertical steam generator (SG) generating saturated steam at 7.2 MPa pressure and 200 deg C feed water temperature at the SG inlet are considered. The results of comparison of variants in water and steam circuits of turbine plants are greatly influenced by integral economy account, i.e. efficiency indexes account under variable conditions of power unit operation. From variants of water and steam circuits of the K-1000-68/1500 turbine plant considered preference is given to the variant with four low pressure heaters with increased up to 1.25 MPa pressure in a deacrator without high pressure heater with pumping intermediate steam superheater condensate into feedwater circuit

[The influence of combinations of alien translocations on in vitro androgenesis in near-isogenic lines of spring bread wheat].

Science.gov (United States)

Sibikeeva, Yu E; Sibikeev, S N

2014-07-01

The features of in vitro androgenesis were studied in Cultured anthers of spring bread wheats L503 and Dobrynya, having 7DS-7DL-7Ae#1 L translocation with genes Lrl9/Sr25 (Lrl9 translocation) from Agropyron elongatum (Host.) P.B. and their near-isogenic lines carrying combinations of Lrl9 translocation with translocations: 1BL-IR#1S with genes Pm8/Sr31/Lr26/Yr9 (Lr26translocation) from Secale cereal L., 4BS-4BL-2R#1L with genes Lr25/Pm7 (Lr25 translocation) from Secale cereal, 3DS-3DL-3Ae#1L with genes Lr24/Sr24 (Lr24 translocation) from Agropyron elongatum and 6BS-6BL-6U#1L with gene Lr9 (Lr9 translocation) from Aegilops umbellulata Zhuk. In comparison with those varieties having received the Lrl9 translocation, the following was established: (1) the combination of translocations Lr19+26 increased embryo frequency and green plant regeneration; (2) the combination of translocations Lr19+9 decreased embryo frequency but increased green plant regeneration; (3) the combination of translocations Lr19+24 decreased embryo frequency but increased green and albino plant regeneration; (4) the combination of translocations Lr19+25 increased embryo frequency and green plant regeneration but decreased albino plant regeneration. Thus, on near-isogenic lines of spring bread wheat, the influences of genotypes of four alien translocation combinations on in vitro androgenesis were determined.

Identification of WOX family genes in Selaginella kraussiana for studies on stem cells and regeneration in lycophytes

Directory of Open Access Journals (Sweden)

Yachao eGe

2016-02-01

Full Text Available Plant stem cells give rise to all tissues and organs and also serve as the source for plant regeneration. The organization of plant stem cells has undergone a progressive change from simple to complex during the evolution of vascular plants. Most studies on plant stem cells have focused on model angiosperms, the most recently diverged branch of vascular plants. However, our knowledge of stem cell function in other vascular plants is limited. Lycophytes and euphyllophytes (ferns, gymnosperms, and angiosperms are two existing branches of vascular plants that separated more than 400 million years ago. Lycophytes retain many of the features of early vascular plants. Based on genome and transcriptome data, we identified WUSCHEL-RELATED HOMEOBOX (WOX genes in Selaginella kraussiana, a model lycophyte that is convenient for in vitro culture and observations of organ formation and regeneration. WOX genes are key players controlling stem cells in plants. Our results showed that the S. kraussiana genome encodes at least eight members of the WOX family, which represent an early stage of WOX family evolution. Identification of WOX genes in S. kraussiana could be a useful tool for molecular studies on the function of stem cells in lycophytes.

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29023 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O9/C7 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... LG_O02/C8 ... 11 2.93 ... 10.1007/s00122-003-1570-z 14740090

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29024 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O9/C7 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... LG_O02/C8 ... 11 4.65 ... 10.1007/s00122-003-1570-z 14740090

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29025 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O9/C7 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... LG_O02/C8 ... 11 4.68 ... 10.1007/s00122-003-1570-z 14740090

The Amount of Regenerated Heat Inside the Regenerator of a Stirling Engine

Directory of Open Access Journals (Sweden)

J. Škorpík

2008-01-01

Full Text Available The paper deals with analytical computing of the regenerated heat inside the regenerator of a Stirling engine. The total sum of the regenerated heat is constructed as a function of the crank angle in the case of Schmidt’s idealization. 

Increase in the rate of recombinants in tomato (Lycopersicon esculentum L.) after in vitro regeneration.

Science.gov (United States)

Sibi, M; Biglary, M; Demarly, Y

1984-07-01

Modification to the cross-over (C. O.) rate of tomato (Lycopersicon esculentum) was attempted by using in vitro plant regeneration. F1 hybrids with the same genetical homozygous background were compared at two loci: "bs-ms32" on chromosome I, and "aa-d" on chromosome II. For each, the genetic distance separating the two markers was about 20 to 30 map units. One cotyledon of each F2 hybrid seedling was used as in vitro tissue culture material, while the rest of the plantlet was grown as a control. Recombination rates of the selfed progenies from each regenerated and matched control couple were compared. For the first set of markers 59,000 seeds were analysed (5 controls' and 7 regenerated progenies), and for the second, 11,000 (5 controls' and 8 regenerated progenies). There were significant increases in the genetic distance between markers in about half the regenerated individuals. For the first set the increases ranged from 6.07 to 6.91 units out of a control distance of the 19.84 to 25.65, corresponding to lengthenings of 30.59 to 35.29%. For the second set they ranged from 4.92 to 6.04 out of a control distance of 25.05 to 26.57, representing increases of 19.64 to 22.75%. Such a phenomenon can be important either from a fundamental or practical viewpoint, regarding selection efficiency in plants, and potential for gene reassortment.

Metabolomic homeostasis shifts after callus formation and shoot regeneration in tomato

Science.gov (United States)

Kumari, Alka; Ray, Kamalika; Sadhna, Sadhna; Pandey, Arun Kumar; Sreelakshmi, Yellamaraju; Sharma, Rameshwar

2017-01-01

Plants can regenerate from a variety of tissues on culturing in appropriate media. However, the metabolic shifts involved in callus formation and shoot regeneration are largely unknown. The metabolic profiles of callus generated from tomato (Solanum lycopersicum) cotyledons and that of shoot regenerated from callus were compared with the pct1-2 mutant that exhibits enhanced polar auxin transport and the shr mutant that exhibits elevated nitric oxide levels. The transformation from cotyledon to callus involved a major shift in metabolite profiles with denser metabolic networks in the callus. In contrast, the transformation from callus to shoot involved minor changes in the networks. The metabolic networks in pct1-2 and shr mutants were distinct from wild type and were rewired with shifts in endogenous hormones and metabolite interactions. The callus formation was accompanied by a reduction in the levels of metabolites involved in cell wall lignification and cellular immunity. On the contrary, the levels of monoamines were upregulated in the callus and regenerated shoot. The callus formation and shoot regeneration were accompanied by an increase in salicylic acid in wild type and mutants. The transformation to the callus and also to the shoot downregulated LST8 and upregulated TOR transcript levels indicating a putative linkage between metabolic shift and TOR signalling pathway. The network analysis indicates that shift in metabolite profiles during callus formation and shoot regeneration is governed by a complex interaction between metabolites and endogenous hormones. PMID:28481937

Triple-membrane reduces need for ion exchange regeneration

International Nuclear Information System (INIS)

Valcour, H.

1989-01-01

Triple-membrane water treatment systems are comprised of ultrafiltration units for pretreatment, electrodialysis reversal primary demineralizers, reverse osmosis secondary demineralizers, portable ion exchange unit polishing demineralizers, and ultraviolet sterilizers. The triple-membrane process is designed to provide an unprecedented degree of pretreatment to maximize efficiency, durability and reliability of the reverse osmosis, whilst reducing the required regeneration frequency of the ion exchange demineralizer by one to two orders of magnitude. (author)

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.

Induction of recessive mutations in potato using tissue culture techniques

International Nuclear Information System (INIS)

Enckevort, L.J.G. van; Hoogkamp, T.J.H.; Bergervoet, J.E.M.; Visser, R.G.F.; Jacobsen, E.; Stiekma, W.J.; Pereira, A.

2001-01-01

In potato, two different in vitro approaches were used to generate recessive mutants. In the first method, monoploid plant material was irradiated to isolate and identify amylose-free (amf) mutants in potato. For isolating secondary mutants in the amf background new monoploids of the amf type were developed. A few selected amf monoploids showed excellent vigour in vitro, large leave; and microtuber formation. A diploid and a monoploid were tested for in vitro mutation induction and irradiated with 0 to 16 Gy X rays. The optimal dose for survival and mutation induction was between 4 and 8 Gy and plants were regenerated from irradiated leaf explants. In the second approach, mutants were induced by insertion of transposable elements in the diploids. This method was used to mutate R genes for resistance to Phytophthora infestans. Diploid heterozygous Rr plants with the immobilised Ds element, closely linked to one of the R genes, were selected. Mobilisation of Ds using Ac element transposase resulted in the selection of plants with active somatic Ds excision frequency of about 10%. In vitro protoplast isolation and plant regeneration from such plants enabled the selection of regenerants with new independent Ds insertions. Hygromycin selection (Ds excision marker on the T-DNA) during protoplast regeneration increased the frequency of Ds excision regenerants to 56%. A total of 582 hygromycin resistant plants were regenerated and selected in vitro. Preliminary analysis of the regenerants showed re-insertions of Ds in the predicted coding sequences of genes. (author)

Electrical stimulation accelerates axonal and functional peripheral nerve regeneration across long gaps.

Science.gov (United States)

Haastert-Talini, Kirsten; Schmitte, Ruth; Korte, Nele; Klode, Dorothee; Ratzka, Andreas; Grothe, Claudia

2011-04-01

Short-term low-frequency electrical stimulation (ESTIM) of proximal peripheral nerve stumps prior to end-to-end coaptation or tubular bridging of small distances has been reported to increase preferential motor reinnervation and functional motor recovery in animal models and human patients undergoing carpal tunnel release surgery. We investigated the effects of ESTIM on regeneration across rat sciatic nerve gaps, which exceed distances that allow spontaneous regeneration. Three different reconstruction approaches were combined with ESTIM in the experimental groups. Nerve gaps (13 mm) were bridged using (I) nerve autotransplantation, (II) transplantation of differentially filled silicone tubes, or (III) transplantation of tubular grafts containing fibroblast growth factor-2 overexpressing Schwann cells (SCs) for gene therapy. The regeneration outcome was followed for up to 8 weeks, and functionally as well as histomorphometrically analyzed in comparison to non-stimulated control groups. Combining ESTIM with nerve autotransplantation significantly increased the nerve fiber density in the regenerated nerve, and the grade of functional recovery as detected by electrodiagnostic recordings from the gastrocnemius muscle. The combination of ESTIM with transplantation of naïve SCs increased the regeneration of gap-bridging nerve tissue. Although macroscopic tissue regeneration was not further improved after combining ESTIM with FGF-2(21/23-kD) gene therapy, the latter resulted in a high rate of regenerated nerves that functionally reconnected to the target muscle. Based on our results, brief ESTIM shows high potential to accelerate axonal as well as functional (motor and sensory) outcomes in the clinical setting of peripheral nerve gap reconstruction in human patients.

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.

"We Was Regenerated Out": Regeneration, Recycling and Devaluing Communities

Directory of Open Access Journals (Sweden)

Luna Glucksberg

2014-12-01

Full Text Available This article looks at well documented processes of urban regeneration and community displacement in the inner-city through an innovative anthropological perspective focused on concepts of waste and value. Using the notion of symbolic devaluation of the working classes developed by Skeggs (1997; 2004, it traces their exclusion from recycling practices while at the same time the estates they live on are being regenerated. Raising questions about the parallels and contradictions between regeneration and recycling, it shows how symbolic devaluation of specifi c areas and their inhabitants are necessary precursors of the physical demolition and removal that characterize regeneration processes. Through an ethnographic approach, the deep connections between people and their waste, and people as waste, are exposed and questioned, showing how valuable middle class selves are produced through appropriate waste management procedures, i.e. individualized recycling, while inner-city, estate dwellers are remade into uncaring, unworthy citizens who cannot take part in this value-producing circuit.

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29022 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O2/C8 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... XsORA43-185/178 LG_O02/C8 ... 17 4.75 ... 10.1007/s00122-003-1570-z 14740090

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29021 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O2/C8 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... XsORA43-185/178 LG_O02/C8 ... 17 4.64 ... 10.1007/s00122-003-1570-z 14740090

QTL list: [PGDBj Registered plant list, Marker list, QTL list, Plant DB link and Genome analysis methods[Archive

Lifescience Database Archive (English)

Full Text Available QT29020 Brassica oleracea Brassicaceae ... regeneration from protoplasts_O2/C8 A trai...t contributing to the plant-regeneration ability of protoplast-derived microcalli ... XsORA43-185/178 LG_O02/C8 ... 16 3 ... 10.1007/s00122-003-1570-z 14740090

Frequency Regulation of a Hybrid Wind–Hydro Power Plant in an Isolated Power System

Directory of Open Access Journals (Sweden)

Guillermo Martínez-Lucas

2018-01-01

Full Text Available Currently, some small islands with high wind potential are trying to reduce the environmental and economic impact of fossil fuels by using renewable resources. Nevertheless, the characteristics of these renewable resources negatively affect the quality of the electrical energy, causing frequency disturbances, especially in isolated systems. In this study, the combined contribution to frequency regulation of variable speed wind turbines (VSWT and a pump storage hydropower plant (PSHP is analyzed. Different control strategies, using the kinetic energy stored in the VSWT, are studied: inertial, proportional, and their combination. In general, the gains of the VSWT controller for interconnected systems proposed in the literature are not adequate for isolated systems. Therefore, a methodology to adjust the controllers, based on exhaustive searches, is proposed for each of the control strategies. The control strategies and methodology have been applied to a hybrid wind–hydro power plant on El Hierro Island in the Canary archipelago. At present, in this isolated power system, frequency regulation is only provided by the PSHP and diesel generators. The improvements in the quality of frequency regulation, including the VSWT contribution, have been proven based on simulating different events related to wind speed, or variations in the power demand.

Coordinated frequency control from offshore wind power plants connected to multi terminal DC system considering wind speed variation

DEFF Research Database (Denmark)

Sakamuri, Jayachandra N.; Altin, Müfit; Hansen, Anca Daniela

2017-01-01

A coordinated fast primary frequency control scheme from offshore wind power plants (OWPPs) integrated to a three terminal high voltage DC (HVDC) system is proposed in this study. The impact of wind speed variation on the OWPP active power output and thus on the AC grid frequency and DC grid...... the active power support from OWPP with a ramp rate limiter and (iii) An alternative method for the wind turbine overloading considering rotor speed. The effectiveness of the proposed control scheme is demonstrated on a wind power plant integrated into a three terminal HVDC system developed in DIg......SILIENT PowerFactory. The results show that the proposed coordinated frequency control method performs effectively at different wind speeds and minimises the secondary effects on frequency and DC voltage....

High frequency plant regeneration from shoot tip explants of ...

African Journals Online (AJOL)

USER

2010-08-02

Aug 2, 2010 ... 16/8-h (light/dark) photoperiod provided by cool white fluorescent light. Multiple .... formation from shoot tip explant of C. colocynthis on MS-medium. S. No. .... micropropagation of Musa sapientum L. (Cavendish Dwarf). Afr. J.

Optimization for zeolite regeneration and nitrogen removal performance of a hypochlorite-chloride regenerant.

Science.gov (United States)

Zhang, Wei; Zhou, Zhen; An, Ying; Du, Silu; Ruan, Danian; Zhao, Chengyue; Ren, Ning; Tian, Xiaoce

2017-07-01

Simultaneous zeolites regeneration and nitrogen removal were investigated by using a mixed solution of NaClO and NaCl (NaClO-NaCl solution), and effects of the regenerant on ammonium removal performance and textural properties of zeolites were analyzed by long-term adsorption and regeneration operations. Mixed NaClO-NaCl solution removed more NH 4 + exchanged on zeolites and converted more of them to nitrogen than using NaClO or NaCl solution alone. Response surface methodological analysis indicated that molar ratio of hypochlorite and nitrogen (ClO - /N), NaCl concentration and pH value all had significant effects on zeolites regeneration and NH 4 + conversion to nitrogen, and the optimum condition was obtained at ClO - /N of 1.75, NaCl concentration of 20 g/L and pH of 10.0. Zeolites regenerated by mixed NaClO-NaCl solution showed higher ammonium adsorption rate and lower capacity than unused zeolites. Zeolites and the regeneration solution were both effective even after 20 cycles of use. Composition and morphological analysis revealed that the main mineral species and surface morphology of zeolites before and after NaClO-NaCl regeneration were unchanged. Textural analysis indicated that NaClO-NaCl regeneration leads to an increased surface area of zeolites, especially the microporosity. The results indicated that NaClO-NaCl regeneration is an attractive method to achieve sustainable removal of nitrogen from wastewater through zeolite. Copyright © 2017 Elsevier Ltd. All rights reserved.

A perfect storm: multiple stressors interact to drive postfire regeneration failure of lodgepole pine and Douglas-fir forests in Yellowstone

Science.gov (United States)

Hansen, W. D.; Braziunas, K. H.; Rammer, W.; Seidl, R.; Turner, M. G.

2017-12-01

Twenty-first century forests will experience increased stress as environmental conditions and disturbance regimes change. Whether forests retain their structure or transitions to alternate states, particularly when affected by multiple stressors, remains unresolved. Subalpine forests in Yellowstone National Park, WY experience large severe wildfires, and postfire-tree regeneration is necessary to assure resilience. Drying is projected, causing frequent larger wildfires that could reduce seed supply and drought that could constrain postfire-seedling establishment. We asked what combinations of warming-drying conditions, increased fire frequency, and increased burned-patch size cause postfire tree-regeneration failure in Yellowstone? We conducted a simulation experiment to identify combinations of fire frequency, fire size, postfire climate, substrate type, and elevation where lodgepole-pine and Douglas-fir regeneration failed. We expected postfire densities to be reduced if burned-patch sizes exceeded effective dispersal distance, sequential fires burned before trees reached reproductive maturity, or drought occurred after fire. We also expected regeneration failure only where multiple stressors occurred simultaneously at low elevation or on poor substrates.Douglas-fir stands were most vulnerable to regeneration failure. 98% of simulated Douglas-fir stands located in the middle of large burned patches failed to regenerate 30 years post fire. Lodgepole-pine stands in the middle of large burned patches failed to regenerate if they were also located at low elevations (93%) or at higher elevations on soils with poor water retention (73%). Stands of serotinous lodgepole (i.e., trees with closed cones that open when heated) also failed to regenerate if fire recurred before trees were reproductively mature (82%). Drought constrained postfire regeneration, yet, enhanced establishment due to release from cold-temperatures during mid-to-late 21st century often outweighed

Bone marrow adipocytes promote the regeneration of stem cells and hematopoiesis by secreting SCF

Science.gov (United States)

Zhou, Bo O.; Yu, Hua; Yue, Rui; Zhao, Zhiyu; Rios, Jonathan J.; Naveiras, Olaia; Morrison, Sean J.

2017-01-01

Endothelial cells and Leptin Receptor+ (LepR+) stromal cells are critical sources of haematopoietic stem cell (HSC) niche factors, including Stem Cell Factor (SCF), in bone marrow. After irradiation or chemotherapy, these cells are depleted while adipocytes become abundant. We discovered that bone marrow adipocytes synthesize SCF. They arise from Adipoq-Cre/ER+ progenitors, which represent ~5% of LepR+ cells, and proliferate after irradiation. Scf deletion using Adipoq-Cre/ER inhibited hematopoietic regeneration after irradiation or 5-fluorouracil treatment, depleting HSCs and reducing mouse survival. Scf from LepR+ cells, but not endothelial, hematopoietic, or osteoblastic cells, also promoted regeneration. In non-irradiated mice, Scf deletion using Adipoq-Cre/ER did not affect HSC frequency in long bones, which have few adipocytes, but depleted HSCs in tail vertebrae, which have abundant adipocytes. A-ZIP/F1 ‘fatless” mice exhibited delayed hematopoietic regeneration in long bones but not in tail vertebrae, where adipocytes inhibited vascularization. Adipocytes are a niche component that promotes hematopoietic regeneration. PMID:28714970

Heritability of regeneration in tissue cultures of sweet potato (Ipomoea batatas L.).

Science.gov (United States)

Templeton-Somers, K M; Collins, W W

1986-03-01

A population of open-pollinated progeny from 12 parents, and the 12 parents, was surveyed for in vitro growth and regeneration characteristics. Four different tissue culture procedures involving different media and the use of different explants to initiate the cultures were used. Petiole explants from young leaves were used as explants for initiation of callus cultures. These were evaluated for callus growth rate, friability, and callus color and texture, before transferring to each of three different regeneration media for evaluation of morphogenetic potential. Small shoot tips also were used to initiate callus cultures, which were evaluated for the same growth characteristics and transferred to growth-regulator free regeneration media. Regeneration occurred through root or shoot regeneration or through embryogenesis. Tissue culture treatment effects, as well as genotypic effects, were highly significant in determining: the types of callus produced, callus growth rates, color and texture on the two types of media used for the second and third subcultures. The family x treatment interaction was generally not statistically significant, affecting only callus color. Estimates of narrow sense heritability for callus growth rate in both the second and third subcultures were high enough (0.35 and 0.63, respectively) for the evaluation of parental lines for selection procedures. These characteristics were also the only early culture callus traits that were consistently correlated with later morphogenesis of the cultures. They were negatively correlated with root or shoot regeneration. The occurence of somatic embryogenesis was not correlated with early callus growth characteristics. Genetic and treatment effects were highly significant in the evaluation of morphogenetic potential, through root or shoot regeneration, or through embryogenesis. Regeneration of all types was of low frequency for all procedures, expressed in ≦ 11% of the cultures of the total population.

Development of efficient catharanthus roseus regeneration and transformation system using agrobacterium tumefaciens and hypocotyls as explants

Directory of Open Access Journals (Sweden)

Wang Quan

2012-06-01

showed that overexpression of DAT increased the yield of vindoline in transgenic plants. Conclusions In the present study, we report an efficient Agrobacterium-mediated transformation system for C. roseus plants with 11% of transformation frequency. To our knowledge, this is the first report on the establishment of A. tumefaciens mediated transformation and regeneration of C. roseus. More importantly, the C. roseus transformation system developed in this work was confirmed in the successful transformation of C. roseus using a key gene DAT involved in TIAs biosynthetic pathway resulting in the higher accumulation of vindoline in transgenic plants.

Plant regeneration from organ culture in white Guinea Yam

Energy Technology Data Exchange (ETDEWEB)

Nwachukwu, E C; Mbanaso, E N.A. [National Root Crops Research Inst., Umudike, Umuahia, Abia State (Nigeria); Sonnino, A [Centro Recerche Energia, ENEA, Rome (Italy)

1997-07-01

Explants from leaves, leaf segments, petioles and internodal stem of in vitro grown seedlings of white guinea yam, Dioscorea rotundata Poir, cv. `Obiaoturugo` were cultured on defined media. NAA at concentrations of 0.5-1.0 mg/1 induced shoot regeneration from petiolar and inter-nodal stem pieces, and rooting occurred with little or no callusing from whole leaves or leaf segments. With concentration of 3.0-10.0 m/1 NAA, explants from petioles, inter-nodal stem, whole leaves and leaf segments formed callus which produced roots. These explants developed plantlets when subcultured on MS medium supplemented with 2.0 mg/1 BAP and 0.1 mg/1 NAA. (author). 11 refs, 1 tab.

Plant regeneration from organ culture in white Guinea Yam

International Nuclear Information System (INIS)

Nwachukwu, E.C.; Mbanaso, E.N.A.; Sonnino, A.

1997-01-01

Explants from leaves, leaf segments, petioles and internodal stem of in vitro grown seedlings of white guinea yam, Dioscorea rotundata Poir, cv. 'Obiaoturugo' were cultured on defined media. NAA at concentrations of 0.5-1.0 mg/1 induced shoot regeneration from petiolar and inter-nodal stem pieces, and rooting occurred with little or no callusing from whole leaves or leaf segments. With concentration of 3.0-10.0 m/1 NAA, explants from petioles, inter-nodal stem, whole leaves and leaf segments formed callus which produced roots. These explants developed plantlets when subcultured on MS medium supplemented with 2.0 mg/1 BAP and 0.1 mg/1 NAA. (author). 11 refs, 1 tab

Proposal of a combined heat and power plant hybridized with regeneration organic Rankine cycle: Energy-Exergy evaluation

International Nuclear Information System (INIS)

Anvari, Simin; Jafarmadar, Samad; Khalilarya, Shahram

2016-01-01

Highlights: • A new thermodynamic cogeneration system is proposed. • Energy and exergy analysis of the considered cycle were performed. • An enhancement of 2.6% in exergy efficiency compared to that of baseline cycle. - Abstract: Among Rankine cycles (simple, reheat and regeneration), regeneration organic Rankine cycle demonstrates higher efficiencies compared to other cases. Consequently, in the present work a regeneration organic Rankine cycle has been utilized to recuperate gas turbine’s heat using heat recovery steam generator. At first, this cogeneration system was subjected to energy and exergy analysis and the obtained results were compared with that of investigated cogeneration found in literature (a cogeneration system in which a reheat organic Rankine cycle for heat recuperation of gas turbine cycle was used with the aid of heat recovery steam generator). Results indicated that the first and second thermodynamic efficiencies in present cycle utilizing regeneration cycle instead of reheat cycle has increased 2.62% and 2.6%, respectively. In addition, the effect of thermodynamic parameters such as combustion chamber’s inlet temperature, gas turbine inlet temperature, evaporator and condenser temperature on the energetic and exergetic efficiencies of gas turbine-heat recovery steam generator cycle and gas turbine-heat recovery steam generator cycle with regeneration organic Rankine cycle was surveyed. Besides, parametric analysis shows that as gas turbine and combustion chamber inlet temperatures increase, energetic and exergetic efficiencies tend to increase. Moreover, once condenser and evaporator temperature raise, a slight decrement in energetic and exergetic efficiency is expected.

Rice is the seed of the monocot plants Oryza sativa (Asian rice) or ...

African Journals Online (AJOL)

BIOTECH

2013-10-16

Oct 16, 2013 ... of culture. The regenerated plantlets were transferred to pots for acclimatization. About 80% of plants were survived in the greenhouse condition. Key words: Somatic embryogenesis, immature zygotic embryos, Indica rice, plant regeneration. INTRODUCTION. Rice (Oryza sativa L.) is one of the most ...

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

International Nuclear Information System (INIS)

Lehner, J.R.; Lin, C.C.; Pratt, W.T.; Su, T.; Danziger, L.

1996-01-01

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

Regeneration of roots from callus reveals stability of the developmental program for determinate root growth in Sonoran Desert Cactaceae.

Science.gov (United States)

Shishkova, Svetlana; García-Mendoza, Edith; Castillo-Díaz, Vicente; Moreno, Norma E; Arellano, Jesús; Dubrovsky, Joseph G

2007-05-01

In some Sonoran Desert Cactaceae the primary root has a determinate root growth: the cells of the root apical meristem undergo only a few cell division cycles and then differentiate. The determinate growth of primary roots in Cactaceae was found in plants cultivated under various growth conditions, and could not be reverted by any treatment tested. The mechanisms involved in root meristem maintenance and determinate root growth in plants remain poorly understood. In this study, we have shown that roots regenerated from the callus of two Cactaceae species, Stenocereus gummosus and Ferocactus peninsulae, have a determinate growth pattern, similar to that of the primary root. To demonstrate this, a protocol for root regeneration from callus was established. The determinate growth pattern of roots regenerated from callus suggests that the program of root development is very stable in these species. These findings will permit future analysis of the role of certain Cactaceae genes in the determinate pattern of root growth via the regeneration of transgenic roots from transformed calli.

Regeneration-associated macrophages: a novel approach to boost intrinsic regenerative capacity for axon regeneration

Directory of Open Access Journals (Sweden)

Min Jung Kwon

2016-01-01

Full Text Available Axons in central nervous system (CNS do not regenerate spontaneously after injuries such as stroke and traumatic spinal cord injury. Both intrinsic and extrinsic factors are responsible for the regeneration failure. Although intensive research efforts have been invested on extrinsic regeneration inhibitors, the extent to which glial inhibitors contribute to the regeneration failure in vivo still remains elusive. Recent experimental evidence has rekindled interests in intrinsic factors for the regulation of regeneration capacity in adult mammals. In this review, we propose that activating macrophages with pro-regenerative molecular signatures could be a novel approach for boosting intrinsic regenerative capacity of CNS neurons. Using a conditioning injury model in which regeneration of central branches of dorsal root ganglia sensory neurons is enhanced by a preceding injury to the peripheral branches, we have demonstrated that perineuronal macrophages surrounding dorsal root ganglia neurons are critically involved in the maintenance of enhanced regeneration capacity. Neuron-derived chemokine (C-C motif ligand 2 (CCL2 seems to mediate neuron-macrophage interactions conveying injury signals to perineuronal macrophages taking on a soley pro-regenerative phenotype, which we designate as regeneration-associated macrophages (RAMs. Manipulation of the CCL2 signaling could boost regeneration potential mimicking the conditioning injury, suggesting that the chemokine-mediated RAM activation could be utilized as a regenerative therapeutic strategy for CNS injuries.

Development of direct somatic embryogenesis and regeneration on citrus sinesis

International Nuclear Information System (INIS)

Chong Saw Peng; Alvina Lindsay Mijen; Rusli Ibrahim

2004-01-01

The plant regeneration processes in Citrus sinensis involves direct somatic embryogenesis. Culture medium used was MS basal supplemented with 50 mg/L sucrose, 0.27% agar and 0.1% vitamin at pH 5.8. Sucrose is the major carbon source for the induction of somatic embryo and also the maturation and germination of somatic embryo. (Author)

Regeneration of Salicaceae riparian forests in the Northern Hemisphere: A new framework and management tool.

Science.gov (United States)

González, Eduardo; Martínez-Fernández, Vanesa; Shafroth, Patrick B; Sher, Anna A; Henry, Annie L; Garófano-Gómez, Virginia; Corenblit, Dov

2018-04-25

Human activities on floodplains have severely disrupted the regeneration of foundation riparian shrub and tree species of the Salicaceae family (Populus and Salix spp.) throughout the Northern Hemisphere. Restoration ecologists initially tackled this problem from a terrestrial perspective that emphasized planting. More recently, floodplain restoration activities have embraced an aquatic perspective, inspired by the expanding practice of managing river flows to improve river health (environmental flows). However, riparian Salicaceae species occupy floodplain and riparian areas, which lie at the interface of both terrestrial and aquatic ecosystems along watercourses. Thus, their regeneration depends on a complex interaction of hydrologic and geomorphic processes that have shaped key life-cycle requirements for seedling establishment. Ultimately, restoration needs to integrate these concepts to succeed. However, while regeneration of Salicaceae is now reasonably well-understood, the literature reporting restoration actions on Salicaceae regeneration is sparse, and a specific theoretical framework is still missing. Here, we have reviewed 105 peer-reviewed published experiences in restoration of Salicaceae forests, including 91 projects in 10 world regions, to construct a decision tree to inform restoration planning through explicit links between the well-studied biophysical requirements of Salicaceae regeneration and 17 specific restoration actions, the most popular being planting (in 55% of the projects), land contouring (30%), removal of competing vegetation (30%), site selection (26%), and irrigation (24%). We also identified research gaps related to Salicaceae forest restoration and discuss alternative, innovative and feasible approaches that incorporate the human component. Copyright © 2018 Elsevier Ltd. All rights reserved.

Analytical one-dimensional frequency response and stability model for PWR nuclear power plants

International Nuclear Information System (INIS)

Hoeld, A.

1975-01-01

A dynamic model for PWR nuclear power plants is presented. The plant is assumed to consist of one-dimensional single-channel core, a counterflow once-through steam generator (represented by two nodes according to the nonboiling and boiling region) and the necessary connection coolant lines. The model describes analytically the frequency response behaviour of important parameters of such a plant with respect to perturbations in reactivity, subcooling or mass flow (both at the entrances to the reactor core and/or the secondary steam generator side), the perturbations in steam load or system pressure (on the secondary side of the steam generator). From corresponding 'open' loop considerations it can then be concluded - by applying the Nyquist criterion - upon the degree of the stability behaviour of the underlying system. Based on this theoretical model, a computer code named ADYPMO has been established. From the knowledge of the frequency response behaviour of such a system, the corresponding transient behaviour with respect to a stepwise or any other perturbation signal can also be calculated by applying an appropriate retransformation method, e.g. by using digital code FRETI. To demonstrate this procedure, a transient experimental curve measured during the pre-operational test period at the PWR nuclear power plant KKS Stade was recalculated using the combination ADYPMO-FRETI. Good agreement between theoretical calculations and experimental results give an insight into the validity and efficiency of the underlying theoretical model and the applied retransformation method. (Auth.)

Gamma-radiation effect on the parameters of the population recovery of plants

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N.I. Ivanishvili

2016-12-01

Full Text Available Investigation of the effects of different physic-chemical factors on the ecosystems is one of the important scientific tasks. From this perspective, it is to be mentioned an effect of such a strong damaging factor as ionizing radiation. Radiation damage is reflected differently in relation to the levels of organization of living organisms. On the relatively early stage of radiation damage determination of post-irradiation regeneration indicators on population level gives possibility to forecast the sustainability of ecosystems. In order to determine the indicators of post-irradiation regeneration of plant populations we have used as a model water plant – Lemna minor L. During the exposure of radiation on different levels of organization differences are identified not only according to qualitative features but also by the character of direction of the development of the processes of postradiation regeneration. A conclusion is made that if during the acute radiation it is possible to determine radioresistance of certain plants, which is based on the plant potential to post-radiation regeneration, the investigation carried out through chronic irradiation gives the possibility to determine the indicators of the ability of the plant to adapt to the radiation.

Suitable Method of Overloading for Fast Primary Frequency Control from Offshore Wind Power Plants in Multi-Terminal DC Grid

DEFF Research Database (Denmark)

Sakamuri, Jayachandra N.; Hansen, Anca Daniela; Altin, Müfit

2017-01-01

Increased penetration of offshore wind power plants (OWPPs) demands frequency control services from them. Overloading the wind turbine, for few seconds after the under frequency event, to utilize its kinetic energy seems promising option for fast primary frequency control. Two methods...

Regeneration in Jatropha curcas: Factors affecting the efficiency of in vitro regeneration

KAUST Repository

Sharma, Sweta K.; Kumar, Nitish Chandramohana; Reddy, Muppala P.

2011-01-01

Factors influencing in vitro regeneration through direct shoot bud induction from hypocotyl explants of Jatropha curcas were studied in the present investigation. Regeneration in J. curcas was found to be genotype dependent and out of four toxic and one non-toxic genotype studied, non-toxic was least responsive. The best results irrespective of genotype were obtained on the medium containing 0.5mgL-1 TDZ (Thidiazuron) and in vitro hypocotyl explants were observed to have higher regeneration efficiency as compared to ex vitro explant in both toxic and non-toxic genotypes. Adventitious shoot buds could be induced from the distal end of explants in all the genotypes. The number of shoot buds formed and not the number of explants responding to TDZ treatment were significantly affected by the position of the explant on the seedling axis. Explants from younger seedlings (≤15 days) were still juvenile and formed callus easily, whereas the regeneration response declined with increase in age of seedlings after 30 days. Transient reduction of Ca2+ concentrations to 0.22gL-1 in the germination medium increased the number of responding explants.Induced shoot buds, upon transfer to MS medium containing 2mgL-1 Kn (Kinetin) and 1mgL-1 BAP (6-benzylamino purine) elongated. These elongated shoots were further proliferated on MS medium supplemented with 1.5mgL-1 IAA (indole-3-acetic acid) and 0.5mgL-1 BAP and 3.01-3.91cm elongation was achieved after 6 weeks. No genotype specific variance in shoot elongation was observed among the toxic genotypes except the CSMCRI-JC2, which showed reduced response. And for proliferation among the toxic genotypes, CSMCRI-JC4 showed highest number of shoots formed. Among the rest, no significant differences were observed. The elongated shoot could be rooted by pulse treatment on half-strength MS medium supplemented with 2% sucrose, 3mgL-1 IBA (indole-3-butyric acid), 1mgL-1 IAA, 1mgL-1 NAA (α-naphthalene acetic acid) and subsequent transfer on 0

Regeneration in Jatropha curcas: Factors affecting the efficiency of in vitro regeneration

KAUST Repository

Sharma, Sweta K.

2011-07-01

Factors influencing in vitro regeneration through direct shoot bud induction from hypocotyl explants of Jatropha curcas were studied in the present investigation. Regeneration in J. curcas was found to be genotype dependent and out of four toxic and one non-toxic genotype studied, non-toxic was least responsive. The best results irrespective of genotype were obtained on the medium containing 0.5mgL-1 TDZ (Thidiazuron) and in vitro hypocotyl explants were observed to have higher regeneration efficiency as compared to ex vitro explant in both toxic and non-toxic genotypes. Adventitious shoot buds could be induced from the distal end of explants in all the genotypes. The number of shoot buds formed and not the number of explants responding to TDZ treatment were significantly affected by the position of the explant on the seedling axis. Explants from younger seedlings (≤15 days) were still juvenile and formed callus easily, whereas the regeneration response declined with increase in age of seedlings after 30 days. Transient reduction of Ca2+ concentrations to 0.22gL-1 in the germination medium increased the number of responding explants.Induced shoot buds, upon transfer to MS medium containing 2mgL-1 Kn (Kinetin) and 1mgL-1 BAP (6-benzylamino purine) elongated. These elongated shoots were further proliferated on MS medium supplemented with 1.5mgL-1 IAA (indole-3-acetic acid) and 0.5mgL-1 BAP and 3.01-3.91cm elongation was achieved after 6 weeks. No genotype specific variance in shoot elongation was observed among the toxic genotypes except the CSMCRI-JC2, which showed reduced response. And for proliferation among the toxic genotypes, CSMCRI-JC4 showed highest number of shoots formed. Among the rest, no significant differences were observed. The elongated shoot could be rooted by pulse treatment on half-strength MS medium supplemented with 2% sucrose, 3mgL-1 IBA (indole-3-butyric acid), 1mgL-1 IAA, 1mgL-1 NAA (α-naphthalene acetic acid) and subsequent transfer on 0

Cisplatin ototoxicity blocks sensory regeneration in the avian inner ear.

Science.gov (United States)

Slattery, Eric L; Warchol, Mark E

2010-03-03

Cisplatin is a chemotherapeutic agent that is widely used in the treatment of solid tumors. Ototoxicity is a common side effect of cisplatin therapy and often leads to permanent hearing loss. The sensory organs of the avian ear are able to regenerate hair cells after aminoglycoside ototoxicity. This regenerative response is mediated by supporting cells, which serve as precursors to replacement hair cells. Given the antimitotic properties of cisplatin, we examined whether the avian ear was also capable of regeneration after cisplatin ototoxicity. Using cell and organ cultures of the chick cochlea and utricle, we found that cisplatin treatment caused apoptosis of both auditory and vestibular hair cells. Hair cell death in the cochlea occurred in a unique pattern, progressing from the low-frequency (distal) region toward the high-frequency (proximal) region. We also found that cisplatin caused a dose-dependent reduction in the proliferation of cultured supporting cells as well as increased apoptosis in those cells. As a result, we observed no recovery of hair cells after ototoxic injury caused by cisplatin. Finally, we explored the potential for nonmitotic hair cell recovery via activation of Notch pathway signaling. Treatment with the gamma-secretase inhibitor N-[N-(3,5-difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester failed to promote the direct transdifferentiation of supporting cells into hair cells in cisplatin-treated utricles. Taken together, our data show that cisplatin treatment causes maintained changes to inner ear supporting cells and severely impairs the ability of the avian ear to regenerate either via proliferation or by direct transdifferentiation.

Vegetative regeneration

Science.gov (United States)

George A. Schier; John R. Jones; Robert P. Winokur

1985-01-01

Aspen is noted for its ability to regenerate vegetatively by adventitious shoots or suckers that arise on its long lateral roots. It also produces sprouts from stumps and root collars; but they are not common. In a survey of regeneration after clearcutting mature aspen in Utah. Baker (1918b) found that 92% of the shoots originated from roots, 7% from root collars, and...

POTENTIAL OF UAV BASED CONVERGENT PHOTOGRAMMETRY IN MONITORING REGENERATION STANDARDS

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U. Vepakomma

2015-08-01

Full Text Available Several thousand hectares of forest blocks are regenerating after harvest in Canada. Monitoring their performance over different stages of growth is critical in ensuring future productivity and ecological balance. Tools for rapid evaluation can support timely and reliable planning of interventions. Conventional ground surveys or visual image assessments are either time intensive or inaccurate, while alternate operational remote sensing tools are unavailable. In this study, we test the feasibility and strength of UAV-based photogrammetry with an EO camera on a UAV platform in assessing regeneration performance. Specifically we evaluated stocking, spatial density and height distribution of naturally growing (irregularly spaced stems or planted (regularly spaced stems conifer regeneration in different phases of growth. Standard photogrammetric workflow was applied on the 785 acquired images for 3D reconstruction of the study sites. The required parameters were derived based on automated single stem detection algorithm developed in-house. Comparing with field survey data, preliminary results hold promise. Future studies are planned to expand the scope to larger areas and different stand conditions.

Biological – chemical regeneration of desulphurization sorbents based on zinc ferrite

Directory of Open Access Journals (Sweden)

Šepelák Vladimír

2002-03-01

Full Text Available One of the main sources of air pollution is the combustion of fuels by various thermal and power plants, transport facilities, and metallurgical plants. Main components of industrial gases that pollute air are carbon oxides, nitrogen oxides, sulphur oxides and hydrogen sulphide. Sulphur has received a more attention than any other contaminant, because the sulphur released into the atmosphere in the form of sulphur dioxide or hydrogen sulphide is a precursor of the “acid rain” formation. To meet environmental emission regulations, sulphur and other contaminant species released during the gasification of coal must be removed from the fuel gas stream. The removal of contaminat at high temperatures is referred to as hot-gas cleanup in general and hot-gas desulphurization in particular when sulphur species are the primary contaminants to be remove. In recent years, zinc ferrite is the leading candidate for hot-gas desulphurization, capable of removing sulphur-containing species from coal gas at gasifier exit temperatures. It can also be of being regenerated for a continuous use. The conventional methods of the regeneration of sulphurized sorbents are based on oxidizing pyrolysis of sulphides or on the pressure leaching of sulphides in the water environment at high temperatures. The first results of the experiments using the biological-chemical leaching, as a new way of regeneration of sulphurized sorbent based on zinc ferrite, are presented in this paper. The results show that the biological-chemical leaching leads to the removal of sulphides layers (á-ZnS, â-ZnS from the surface of the sorbent at room temperature. The biological-chemical leaching process results in the increase of the active surface area of the regenerated sorbent.

Phase regeneration of DPSK signals in a silicon waveguide with reverse-biased p-i-n junction

DEFF Research Database (Denmark)

Da Ros, Francesco; Vukovic, Dragana; Gajda, Andrzej

2014-01-01

Phase regeneration of differential phase-shift keying (DPSK) signals is demonstrated using a silicon waveguide as nonlinear medium for the first time. A p-i-n junction across the waveguide enables decreasing the nonlinear losses introduced by free-carrier absorption (FCA), thus allowing phase......-sensitive extinction ratios as high as 20 dB to be reached under continuous-wave (CW) pumping operation. Furthermore the regeneration properties are investigated under dynamic operation for a 10-Gb/s DPSK signal degraded by phase noise, showing receiver sensitivity improvements above 14 dB. Different phase noise...... frequencies and amplitudes are examined, resulting in an improvement of the performance of the regenerated signal in all the considered cases....

Experience in connecting the power generating units of thermal power plants to automatic secondary frequency regulation within the united power system of Russia

International Nuclear Information System (INIS)

Zhukov, A. V.; Komarov, A. N.; Safronov, A. N.; Barsukov, I. V.

2009-01-01

The principles of central control of the power generating units of thermal power plants by automatic secondary frequency and active power overcurrent regulation systems, and the algorithms for interactions between automatic power control systems for the power production units in thermal power plants and centralized systems for automatic frequency and power regulation, are discussed. The order of switching the power generating units of thermal power plants over to control by a centralized system for automatic frequency and power regulation and by the Central Coordinating System for automatic frequency and power regulation is presented. The results of full-scale system tests of the control of power generating units of the Kirishskaya, Stavropol, and Perm GRES (State Regional Electric Power Plants) by the Central Coordinating System for automatic frequency and power regulation at the United Power System of Russia on September 23-25, 2008, are reported.

Supercritical fluid regeneration of adsorbents

Science.gov (United States)

Defilippi, R. P.; Robey, R. J.

1983-05-01

The results of a program to perform studies supercritical (fluid) carbon dioxide (SCF CO2) regeneration of adsorbents, using samples of industrial wastewaters from manufacturing pesticides and synthetic solution, and to estimate the economics of the specific wastewater treatment regenerations, based on test data are given. Processing costs for regenerating granular activated carbon GAC) for treating industrial wastewaters depend on stream properties and regeneration throughput.

Microwave Regenerable Air Purification Device

Science.gov (United States)

Atwater, James E.; Holtsnider, John T.; Wheeler, Richard R., Jr.

1996-01-01

The feasibility of using microwave power to thermally regenerate sorbents loaded with water vapor, CO2, and organic contaminants has been rigorously demonstrated. Sorbents challenged with air containing 0.5% CO2, 300 ppm acetone, 50 ppm trichloroethylene, and saturated with water vapor have been regenerated, singly and in combination. Microwave transmission, reflection, and phase shift has also been determined for a variety of sorbents over the frequency range between 1.3-2.7 GHz. This innovative technology offers the potential for significant energy savings in comparison to current resistive heating methods because energy is absorbed directly by the material to be heated. Conductive, convective and radiative losses are minimized. Extremely rapid heating is also possible, i.e., 1400 C in less than 60 seconds. Microwave powered thermal desorption is directly applicable to the needs of Advance Life Support in general, and of EVA in particular. Additionally, the applicability of two specific commercial applications arising from this technology have been demonstrated: the recovery for re-use of acetone (and similar solvents) from industrial waste streams using a carbon based molecular sieve; and the separation and destruction of trichloroethylene using ZSM-5 synthetic zeolite catalyst, a predominant halocarbon environmental contaminant. Based upon these results, Phase II development is strongly recommended.

Effect of high frequency content of uniform hazard response spectra on nuclear power plant structures, systems and components

Energy Technology Data Exchange (ETDEWEB)

Usmani, A. [Amec Foster Wheeler, Toronto, ON (Canada); Baughman, P.D. [Paul D. Baughman Consulting, Exeter, NH (United States)

2015-07-01

The Uniform Hazard Spectrum (UHS) is developed from a probabilistic seismic hazard assessment and represents a response spectrum for which the amplitude at each frequency has a specified and uniform (equal) probability of exceedance. The high spectral acceleration at high frequencies in the UHS can result mainly from small non-damaging low energy earthquakes. Historically Canadian and U.S. nuclear power plants have been designed using the standard shape spectrum given in CSA N289.3 or USNRC Regulatory Guide 1.60, which have maximum spectral accelerations in the lower (2-10 Hz.) frequency range. The impact of the high frequency content of UHS on the nuclear power plant SSCs is required to be assessed. This paper briefly describes the methodologies used for screening and evaluation of the effects of UHS high frequency content on the nuclear power SSCs that have been designed using the CSA N289.3 standard shape spectrum. (author)

ORC power plant for electricity production from forest and agriculture biomass

International Nuclear Information System (INIS)

Borsukiewicz-Gozdur, A.; Wiśniewski, S.; Mocarski, S.; Bańkowski, M.

2014-01-01

Highlights: • Results for three variants of CHP plant fuelled by sawmill biomass are presented. • Octamethyltrisiloxane, MDM, methanol and H 2 O working fluids was conducted in CHP. • CHP with internal regeneration and “dry” working fluid has the highest electric power. • Power output, drying heat and drying temperature depend on CHP variant and ORC fluid. - Abstract: The paper presents the calculation results for three variants of CHP plant fuelled by sawmill biomass. The plant shall produce electricity and heat for a drying chamber. An analysis of the system efficiency for four different working fluids was conducted: octamethyltrisiloxane, methylcyclohexane, methanol and water. The highest electric power was obtained for the system with internal regeneration and methylcyclohexane applied as the “dry” working fluid, the highest temperature to supply the drying chamber was obtained for the system with external regeneration and octamethyltrisiloxane applied as the working fluid. The results of the analysis indicate that, by proper choice of the working fluid and of the regeneration variant (internal or external), it is possible to “adjust” the work of the system to the needs and expectations of the plant investor (user)

Removal of mercury from coal-combustion flue gas using regenerable sorbents

Energy Technology Data Exchange (ETDEWEB)

Turchi, C S; Albiston, J; Broderick, T E; Stewart, R M

1999-07-01

The US EPA estimates that coal-fired power plants constitute the largest anthropogenic source of mercury emissions in the US. The Agency has contemplated emission regulations for power plants, but the large gas-flow rates and low mercury concentrations involved have made current treatment options prohibitively expensive. ADA Technologies, Inc. (Englewood, Colorado), in conjunction with the US DOE, is developing regenerable sorbents for the removal and recovery of mercury from flue gas. These sorbents are based on the ability of noble metals to amalgamate mercury at typical flue-gas temperatures and release mercury at higher temperatures. The process allows for recovery of mercury with minimal volumes of secondary wastes and no impact on fly ash quality. In 1997 and 1998, ADA tested a 20-cfm sorbent unit at CONSOL Inc.'s coal-combustion test facility in Library, PA. Results from the 1997 tests indicated that the sorbent can remove elemental and oxidized mercury and can be regenerated without loss of capacity. Design changes were implemented in 1998 to enhance the thermal efficiency of the process and to recover the mercury in a stable form. Testing during autumn, 1998 demonstrated 60% to 90% removal efficiency of mercury from a variety of different coals. However, contradictory removal results were obtained at the end of the test period. Subsequent laboratory analyses indicated that the sorbent had lost over half its capacity for mercury due to a decrease in available sites for mercury sorption. The presence of sulfur compounds on the sorbent suggests that thermal cycling may have condensed acid gases on the sorbent leading to deterioration of the active sorption sites. The regeneration time/temperature profile has been altered to minimize this potential in the upcoming power plant tests.

Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub

Science.gov (United States)

Delerue, Florian; Gonzalez, Maya; Michalet, Richard; Pellerin, Sylvain; Augusto, Laurent

2015-01-01

The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation) due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development) as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se) and the physical world where the seedlings appear and develop (the regeneration habitat). PMID:26098877

Weak Evidence of Regeneration Habitat but Strong Evidence of Regeneration Niche for a Leguminous Shrub.

Directory of Open Access Journals (Sweden)

Florian Delerue

Full Text Available The identification of an ecological niche specific to the regeneration phase has mobilised significant attention. However, the importance of the regeneration niche concept remains unclear. Our main objective was to study the existence of such a regeneration niche for a leguminous shrub, Ulex europaeus. This study was carried out in southwest France in the context of water and nutrient stresses (mainly phosphorus limitation due to the presence of nutrient-poor sandy soils. We analysed the regeneration of the species from the germination of seeds and emergence of new seedlings until the seedlings reached young shrub size. Our design included a P fertilisation treatment. We also investigated microsite characteristics (micro-topography and vegetation development as they can interact with meteorological conditions and determine water availability for seeds and seedlings. We found that P availability controlled seedling growth and the time necessary to reach young shrub size. Water availability appeared to impact the species germination and seedlings survival. We also found that P and water availability depended on the interactions between microsite characteristics and climatic variations. Finally we found evidence that P and water availability are important ecological factors shaping the regeneration niche of the species, but we found weak evidence that any microsite would be appropriate for the regeneration of the species in the long term. Future studies regarding regeneration niches need to distinguish more clearly the ecological factors important for regeneration (the regeneration niche per se and the physical world where the seedlings appear and develop (the regeneration habitat.

In vitro propagation and conservation of Satureja avromanica Maroofi-an indigenous threatened medicinal plant of Iran.

Science.gov (United States)

Mozafari, Ali Akbar; Vafaee, Yavar; Karami, Edris

2015-07-01

An efficient and rapid in vitro propagation system for Satureja avromanica, a rare and endangered folk medicinal plant of Iran was developed through the shoot tip and leaf disc explants. Nodal and leaf explants from wild plants were established on MS and WPM media supplemented with BA, BAP and TDZ (0, 0.1, 0.5, 1, 1.5, 2, 5 and 10 mgl(-1)) alone or by application of BA and TDZ (0, 2, 5 and 10 mgl(-1)) in combination with IBA and 2,4-D (0, 0.1, 0.5 and 1 mgl(-1)), respectively. Based on results, the highest mean shoot number (6.21) was obtained on MS medium supplemented with 2 mgl(-1) BA. Regarding the shoot elongation, MS supplemented with 2 mgl(-1) TDZ and MS containing 5 mgl(-1) BA showed the longest shoots (4.82 and 4.39 cm, respectively) after 6 weeks of culture. As a matter of fact, increasing all three tested cytokinins levels led to enhancement of explant response frequency and regenerated shoot number. On the other side, WPM medium supplemented with 0.1 mgl(-1) IBA was found suitable for rooting of regenerated shoots. RAPD molecular analysis revealed genetic stability of in vitro raised plants. In conclusion, individual application of BA, BAP and TDZ were in favor of S. avromanica direct shoot regeneration while treatment media with a combination of IBA and BA as well as 2,4-D and TDZ resulted in callogenesis in most explants. Finally, the in vitro raised plantlets were acclimatized and successfully established in the greenhouse conditions. Our developed protocol can be employed for the large-scale micropropagation and conservation of S. avromanica as a threatened medicinal plant.

Studying the effects of combining internal and external heat recovery on techno-economic performances of gas–steam power plants

International Nuclear Information System (INIS)

Carapellucci, Roberto; Giordano, Lorena

2016-01-01

Highlights: • Effects of gas-cycle regeneration on steam–gas power plants are investigated. • Power plant performances are evaluated varying gas turbine operative parameters. • The power plant operational flexibility is assessed through an off-design analysis. • Gas-cycle regeneration improves energy and economic performance parameters. • Power increase due to regenerator by-pass depends on steam section design. - Abstract: Thermodynamic regeneration is regarded as a conventional technique to enhance the efficiency of gas turbines, by means of an internal recovery of waste heat from exhaust gases. In combined cycle power plants (CCGTs), only external heat recovery is usually applied, in order to achieve the highest steam cycle power. Combining internal and external recovery, while decreasing the power plant rated capacity, has the potential to boost the efficiency of CCGTs. This paper aims to examine the effects of thermodynamic regeneration on steam–gas power plants from the energy and economic point of view. First, a dual pressure combined cycle based on a regenerative gas turbine is designed using GateCycle software and effects on energy and economic performances are evaluated varying gas turbine operating parameters. Then, an off-design simulation of different CCGT configurations is carried out, in order to evaluate the power increase achieved by-passing the regenerator and its effects on efficiency and cost of electricity. The study has shown that the improvement of energy and economic performances of regenerative CCGTs is more and more pronounced with the increase of turbine inlet temperature (TIT). Additionally, regeneration enhances the power plant operational flexibility, allowing to obtain a 30% power increase with respect to the design value, if the regenerator is fully by-passed and the bottoming steam cycle is designed to manage the increased flue gas temperature.

Understanding Urban Regeneration in Turkey

Science.gov (United States)

Candas, E.; Flacke, J.; Yomralioglu, T.

2016-06-01

In Turkey, rapid population growth, informal settlements, and buildings and infrastructures vulnerable to natural hazards are seen as the most important problems of cities. Particularly disaster risk cannot be disregarded, as large parts of various cities are facing risks from earthquakes, floods and landslides and have experienced loss of lives in the recent past. Urban regeneration is an important planning tool implemented by local and central governments in order to reduce to disaster risk and to design livable environments for the citizens. The Law on the Regeneration of Areas under Disaster Risk, commonly known as the Urban Regeneration Law, was enacted in 2012 (Law No.6306, May 2012). The regulation on Implementation of Law No. 6306 explains the fundamental steps of the urban regeneration process. The relevant institutions furnished with various authorities such as expropriation, confiscation and changing the type and place of your property which makes urban regeneration projects very important in terms of property rights. Therefore, urban regeneration projects have to be transparent, comprehensible and acceptable for all actors in the projects. In order to understand the urban regeneration process, the legislation and projects of different municipalities in Istanbul have been analyzed. While some steps of it are spatial data demanding, others relate to land values. In this paper an overview of the urban regeneration history and activities in Turkey is given. Fundamental steps of the urban regeneration process are defined, and particularly spatial-data demanding steps are identified.

In-vitro neoformation of woody plants (apple, pear, Weigela)

International Nuclear Information System (INIS)

Chevreau, E.; Dufour, M.; Duron, M.

1990-01-01

Full text: Adventitious bud neoformation may induce variability in two ways: somaclonal variation, if the explant has undergone undifferentiated growth (callus); induced mutations, if a physical or chemical mutagen has been applied to the explant prior to the regeneration. Three apple scion cultivars ('Gala', 'Granny Smith', 'Golden Delicious') and four apple rootstock cultivars ('Mark', 'Novole', 'Lancep', 'Cepiland') were grown on basal apple multiplication medium. Leaves, internodes and roots were used for callogenesis and/or regeneration experiments. Scion varieties were more responsive than rootstocks. 1000 'Gala' neoformations will be planted in the field to investigate somaclonal variation. In pear, shoot regeneration was obtained from in-vitro leaves of 3 varieties of Pyrus communis ('Seckel', 'Louise Bonne', 'Comice') and one variety of Pyrus bretschneideri ('Crystal Pear'). It was observed that regeneration is still possible from leaves irradiated with up to 40 Gy of γ rays, or treated with 5mM ENU for one hour. In Weigela, stem segments (0.5 cm) from rooted in vitro plants of 5 cultivars were used in experiments to induce adventitious buds. On the cultivar 'Eva Rathke' the adventitious buds were detected as early as 10 to 15 days after the beginning of the culture. A mutagenic treatment was carried out by immersing explants of 'Bristol Ruby' in a suspension of ethyl methane sulfonate (EMS). Among 400 plants regenerated from treated explants, 5 mutants were detected after 5 years of field observation. Two of them seem to be solid mutants. Apparently in Weigela both homogeneous mutants and chimeras are produced by adventitious regeneration from mutagenised explants. (author)

The regeneration test of the secondary loop condensate polishing mixed bed resin in Qinshan NPP

International Nuclear Information System (INIS)

Xu Meijing; Dong Liming

1995-12-01

There are four condensate polishing mixed beds in the water chemical treatment plant of Qinshan NPP. 2125 kg of D001-TR type cation exchange resin, 2000 kg of D201-TR type anion exchange resin, and 375 kg of S-TR type inert resin are filled into each mixed bed. The bed height of resin is 1.2 m and the volume is about 2.7 m 3 . In order to regenerate the exhausted resin out of the bed, the pre-designed condensate polishing mixed bed regeneration process was used to regenerate the first exhausted resin. After the resin was scrubbed and separated, cation resin and anion resin were respectively regenerated, rinsed to resume the exchange capability of the resin. The regenerated mixed bed is able to keep higher efficiency for condensate polishing. The outlet water quality and the resin service-life are able to meet the design requirements or more favorable than that. During the test, some main cations and anions in the blow-off water at each procedure were analyzed. The analyzed results were used to make pre-designed regeneration process better. The test results proved that pre-designed process is reasonable and effective. (6 refs., 6 figs., 7 tabs.)

Nerve Regeneration in the Peripheral Nervous System versus the Central Nervous System and the Relevance to Speech and Hearing after Nerve Injuries

Science.gov (United States)

Gordon, Tessa; Gordon, Karen

2010-01-01

Schwann cells normally form myelin sheaths around axons in the peripheral nervous system (PNS) and support nerve regeneration after nerve injury. In contrast, nerve regeneration in the central nervous system (CNS) is not supported by the myelinating cells known as oligodendrocytes. We have found that: 1) low frequency electrical stimulation can be…

Seedling stage strategies as a means of habitat specialization in herbaceous plants

DEFF Research Database (Denmark)

ten Brink, Dirk-Jan; Bruun, Hans Henrik

2011-01-01

The regeneration niche has been little investigated in studies of community assembly and plant distribution. We examined adaptive associations between seedling traits and habitat specialization. Two habitat contrasts were investigated across several evolutionary lineages of angiosperms: species...... specialized to forest vs. open habitats and to dry vs. wet habitats. We also tested whether effects of shade and drought vary independently or, alternatively, if shade may amplify effects on drought-stressed plants. Seedling response in terms of growth rate, height, slenderness, specific leaf area (SLA......) and degree of elongation (longest internode; petiole or leaf-sheath depending on species' morphology) to light and watering treatments was assessed. We used a factorial design involving three light regimes and two watering frequencies. The open-shaded habitat contrast and the dry-wet habitat contrast were...

Bone marrow adipocytes promote the regeneration of stem cells and haematopoiesis by secreting SCF.

Science.gov (United States)

Zhou, Bo O; Yu, Hua; Yue, Rui; Zhao, Zhiyu; Rios, Jonathan J; Naveiras, Olaia; Morrison, Sean J

2017-08-01

Endothelial cells and leptin receptor + (LepR + ) stromal cells are critical sources of haematopoietic stem cell (HSC) niche factors, including stem cell factor (SCF), in bone marrow. After irradiation or chemotherapy, these cells are depleted while adipocytes become abundant. We discovered that bone marrow adipocytes synthesize SCF. They arise from Adipoq-Cre/ER + progenitors, which represent ∼5% of LepR + cells, and proliferate after irradiation. Scf deletion using Adipoq-Cre/ER inhibited haematopoietic regeneration after irradiation or 5-fluorouracil treatment, depleting HSCs and reducing mouse survival. Scf from LepR + cells, but not endothelial, haematopoietic or osteoblastic cells, also promoted regeneration. In non-irradiated mice, Scf deletion using Adipoq-Cre/ER did not affect HSC frequency in long bones, which have few adipocytes, but depleted HSCs in tail vertebrae, which have abundant adipocytes. A-ZIP/F1 'fatless' mice exhibited delayed haematopoietic regeneration in long bones but not in tail vertebrae, where adipocytes inhibited vascularization. Adipocytes are a niche component that promotes haematopoietic regeneration.

Simulated big sagebrush regeneration supports predicted changes at the trailing and leading edges of distribution shifts

Science.gov (United States)

Schlaepfer, Daniel R.; Taylor, Kyle A.; Pennington, Victoria E.; Nelson, Kellen N.; Martin, Trace E.; Rottler, Caitlin M.; Lauenroth, William K.; Bradford, John B.

2015-01-01

Many semi-arid plant communities in western North America are dominated by big sagebrush. These ecosystems are being reduced in extent and quality due to economic development, invasive species, and climate change. These pervasive modifications have generated concern about the long-term viability of sagebrush habitat and sagebrush-obligate wildlife species (notably greater sage-grouse), highlighting the need for better understanding of the future big sagebrush distribution, particularly at the species' range margins. These leading and trailing edges of potential climate-driven sagebrush distribution shifts are likely to be areas most sensitive to climate change. We used a process-based regeneration model for big sagebrush, which simulates potential germination and seedling survival in response to climatic and edaphic conditions and tested expectations about current and future regeneration responses at trailing and leading edges that were previously identified using traditional species distribution models. Our results confirmed expectations of increased probability of regeneration at the leading edge and decreased probability of regeneration at the trailing edge below current levels. Our simulations indicated that soil water dynamics at the leading edge became more similar to the typical seasonal ecohydrological conditions observed within the current range of big sagebrush ecosystems. At the trailing edge, an increased winter and spring dryness represented a departure from conditions typically supportive of big sagebrush. Our results highlighted that minimum and maximum daily temperatures as well as soil water recharge and summer dry periods are important constraints for big sagebrush regeneration. Overall, our results confirmed previous predictions, i.e., we see consistent changes in areas identified as trailing and leading edges; however, we also identified potential local refugia within the trailing edge, mostly at sites at higher elevation. Decreasing

High frequency, high amplitude and low energy earthquake study of nuclear power plants

International Nuclear Information System (INIS)

Bernero, R.M.; Lee, A.J.H.; Sobel, P.A.

1988-01-01

Nuclear power plants are designed for a seismic input spectrum based on U.S. acceleration time histories. However, data recorded near several earthquakes, mostly in the Eastern U.S., are richer in high frequency energy. This paper focuses on the evaluation of one of these events, i.e., the 1986 Ohio earthquake approximately 10 miles from the Perry nuclear power plant. The Perry Seismic Category I structures were reanalyzed using the in-structure recorded earthquake motions. The calculated in-structure response spectra and recorded response spectra have the same general trends, which shows the buildings are capable of responding to high frequency earthquake motion. Dynamic stresses calculated using the Ohio earthquake recorded motions are substantially lower than the design stresses. The seismic qualification of a wide sample of equipment was reassessed using the Ohio earthquake recorded motions and the margins were found to be larger than one. The 1986 Ohio earthquake was also shown to possess much lower energy content and ductility demand than the design spectra. For the Perry case, the seismic design was shown to have adequate safety margins to accommodate the 1986 Ohio earthquake, even though the design spectra were exceeded at about 20 Hz. The NRC is evaluating the need to generically modify design spectra in light of the recent high frequency recordings. (orig.)

Contribution to the study of the degradation of the solvent used in a nuclear fuel reprocessing plant

International Nuclear Information System (INIS)

Goasmat, F.

1984-01-01

The degradation of a mixed solvent (tributylphosphate - hydrocarbons) in a fuel reprocessing plant (UP 2 at La Hague, France) is studied in this thesis. Laboratory studies on degradation mechanisms, decomposition products and regeneration processes are reviewed in a bibliographic synthesis. Solvent degradation is investigated on a real solvent from a reprocessing plant. Influence of degradation on solvent performance is shown and regeneration processes should be improved. Many regeneration processes are tested on solvent from the plant and results are discussed. Separation and analysis of degradation products show the polyfunctional structure of compounds formed [fr

An active magnetic regenerator device

DEFF Research Database (Denmark)

2015-01-01

A rotating active magnetic regenerator (AMR) device comprising two or more regenerator beds, a magnet arrangement and a valve arrangement. The valve arrangement comprises a plurality of valve elements arranged substantially immovably with respect to the regenerator beds along a rotational direction...

On marginal regeneration

NARCIS (Netherlands)

Stein, H.N.

1991-01-01

On applying the marginal regeneration concept to the drainage of free liquid films, problems are encountered: the films do not show a "neck" of minimum thickness at the film/border transition; and the causes of the direction dependence of the marginal regeneration are unclear. Both problems can be

The effect of uncertainties in nuclear reactor plant-specific failure data on core damage frequency

International Nuclear Information System (INIS)

Martz, H.F.

1995-05-01

It is sometimes the case in PRA applications that reported plant-specific failure data are, in fact, only estimates which are uncertain. Even for detailed plant-specific data, the reported exposure time or number of demands is often only an estimate of the actual exposure time or number of demands. Likewise the reported number of failure events or incidents is sometimes also uncertain because incident or malfunction reports may be ambiguous. In this report we determine the corresponding uncertainty in core damage frequency which can b attributed to such uncertainties in plant-specific data using a simple but typical nuclear power reactor example

An efficient somatic embryogenesis based plant regeneration from ...

African Journals Online (AJOL)

ajl yemi

2010-03-05

Mar 5, 2010 ... Fang Yuan, Quan Wang, Qifang Pan, Guofeng Wang, Jingya Zhao, Yuesheng Tian and. Kexuan Tang*. Plant Biotechnology Research Center, School of Agriculture and Biology, Fudan-SJTU-Nottingham Plant Biotechnology. R&D Center, Shanghai Jiao Tong University, Shanghai 200240, P. R. China.

Isozyme modifications and plant regeneration through somatic embryogenesis in sweet potato (Ipomoea batatas (L.) Lam.).

Science.gov (United States)

Cavalcante Alves, J M; Sihachakr, D; Allot, M; Tizroutine, S; Mussio, I; Servaes, A; Ducreux, G

1994-05-01

The potential of somatic embryogenesis was evaluated for 10 cultivars of sweet potato through extensive embryogenic response and isozyme analysis. Embryogenic callus was induced by incubating lateral buds on Murashige and Skoog medium containing 10 μM 2,4-dichlorophenoxyacetic acid for 6-8 weeks. The frequency of embryogenic response was low, and varied with genotypes, ranging from 0 to 17%. Embryo to plantlet formation could be enhanced by the use of the combination of 2,4-dichlorophenoxyacetic acid with kinetin, both used at 0.01 μM. Embryogenic callus with its potential of plantlet formation has constantly been maintained for over two years. However, after several subcultures, 0.5 to 12% of embryogenic callus reverted irreversibly into friable fast-growing non-embryogenic callus whose ability to regenerate shoots was then definitively lost. The isozymes of esterase, peroxidase, glutamate oxaloacetate transaminase and acid phosphatase investigated in this study were found appropriate to distinguish compact embryogenic from friable non-embryogenic callus in sweet potato. In fact, the callus reversion was associated with a loss of bands or a decline in isozyme activity. On the contrary, very small changes in isozyme activity or no specific changes at all were observed during the differentiation of embryogenic callus into globular embryos.

Perfluorodecalin and bone regeneration

Directory of Open Access Journals (Sweden)

F Tamimi

2013-01-01

Full Text Available Perfluorodecalin (PFD is a chemically and biologically inert biomaterial and, as many perfluorocarbons, is also hydrophobic, radiopaque and has a high solute capacity for gases such as oxygen. In this article we have demonstrated, both in vitro and in vivo, that PFD may significantly enhance bone regeneration. Firstly, the potential benefit of PFD was demonstrated by prolonging the survival of bone marrow cells cultured in anaerobic conditions. These findings translated in vivo, where PFD incorporated into bone-marrow-loaded 3D-printed scaffolds substantially improved their capacity to regenerate bone. Secondly, in addition to biological applications, we have also shown that PFD improves the radiopacity of bone regeneration biomaterials, a key feature required for the visualisation of biomaterials during and after surgical implantation. Finally, we have shown how the extreme hydrophobicity of PFD enables the fabrication of highly cohesive self-setting injectable biomaterials for bone regeneration. In conclusion, perfluorocarbons would appear to be highly beneficial additives to a number of regenerative biomaterials, especially those for bone regeneration.

Early regulation of axolotl limb regeneration.

Science.gov (United States)

Makanae, Aki; Satoh, Akira

2012-10-01

Amphibian limb regeneration has been studied for a long time. In amphibian limb regeneration, an undifferentiated blastema is formed around the region damaged by amputation. The induction process of blastema formation has remained largely unknown because it is difficult to study the induction of limb regeneration. The recently developed accessory limb model (ALM) allows the investigation of limb induction and reveals early events of amphibian limb regeneration. The interaction between nerves and wound epidermis/epithelium is an important aspect of limb regeneration. During early limb regeneration, neurotrophic factors act on wound epithelium, leading to development of a functional epidermis/epithelium called the apical epithelial cap (AEC). AEC and nerves create a specific environment that inhibits wound healing and induces regeneration through blastema formation. It is suggested that FGF-signaling and MMP activities participate in creating a regenerative environment. To understand why urodele amphibians can create such a regenerative environment and humans cannot, it is necessary to identify the similarities and differences between regenerative and nonregenerative animals. Here we focus on ALM to consider limb regeneration from a new perspective and we also reported that focal adhesion kinase (FAK)-Src signaling controlled fibroblasts migration in axolotl limb regeneration. Copyright © 2012 Wiley Periodicals, Inc.

Understory response to varying fire frequencies after 20 years of prescribed burning in an upland oak forest

Science.gov (United States)

Burton, J.A.; Hallgren, S.W.; Fuhlendorf, S.D.; Leslie, David M.

2011-01-01

Ecosystems in the eastern United States that were shaped by fire over thousands of years of anthropogenic burning recently have been subjected to fire suppression resulting in significant changes in vegetation composition and structure and encroachment by invasive species. Renewed interest in use of fire to manage such ecosystems will require knowledge of effects of fire regime on vegetation. We studied the effects of one aspect of the fire regime, fire frequency, on biomass, cover and diversity of understory vegetation in upland oak forests prescribe-burned for 20 years at different frequencies ranging from zero to five fires per decade. Overstory canopy closure ranged from 88 to 96% and was not affected by fire frequency indicating high tolerance of large trees for even the most frequent burning. Understory species richness and cover was dominated by woody reproduction followed in descending order by forbs, C3 graminoids, C4 grasses, and legumes. Woody plant understory cover did not change with fire frequency and increased 30% from one to three years after a burn. Both forbs and C3 graminoids showed a linear increase in species richness and cover as fire frequency increased. In contrast, C4 grasses and legumes did not show a response to fire frequency. The reduction of litter by fire may have encouraged regeneration of herbaceous plants and helped explain the positive response of forbs and C3 graminoids to increasing fire frequency. Our results showed that herbaceous biomass, cover, and diversity can be managed with long-term prescribed fire under the closed canopy of upland oak forests. ?? 2011 Springer Science+Business Media B.V.

Progressive erosion of genetic and epigenetic variation in callus-derived cocoa (Theobroma cacao) plants.

Science.gov (United States)

Rodríguez López, Carlos M; Wetten, Andrew C; Wilkinson, Michael J

2010-06-01

*Relatively little is known about the timing of genetic and epigenetic forms of somaclonal variation arising from callus growth. We surveyed for both types of change in cocoa (Theobroma cacao) plants regenerated from calli of various ages, and also between tissues from the source trees. *For genetic change, we used 15 single sequence repeat (SSR) markers from four source trees and from 233 regenerated plants. For epigenetic change, we used 386 methylation-sensitive amplified polymorphism (MSAP) markers on leaf and explant (staminode) DNA from two source trees and on leaf DNA from 114 regenerants. *Genetic variation within source trees was limited to one slippage mutation in one leaf. Regenerants were far more variable, with 35% exhibiting at least one mutation. Genetic variation initially accumulated with culture age but subsequently declined. MSAP (epigenetic) profiles diverged between leaf and staminode samples from source trees. Multivariate analysis revealed that leaves from regenerants occupied intermediate eigenspace between leaves and staminodes of source plants but became progressively more similar to source tree leaves with culture age. *Statistical analysis confirmed this rather counterintuitive finding that leaves of 'late regenerants' exhibited significantly less genetic and epigenetic divergence from source leaves than those exposed to short periods of callus growth.

Low intensity radiation in diapazone of high frequency as factor of the survival modification of differentiated plant cells

International Nuclear Information System (INIS)

Tordiya, N.V.

2005-01-01

The combined effect of low intensity electromagnetic emission in high frequency range (EMI HF) and ionizing radiation on survival of the differential cells of high plant water Elodea canadensis is investigated. It was established, that EMI HF is radioprotective modification of the radiation injury of plant cell

Assessment of Direct Regeneration in Germany (Matricaria chamomilla L. and Shirazi Chamomiles (Matricaria recutita L.

Directory of Open Access Journals (Sweden)

A. Masoumiasl

2016-07-01

Full Text Available Introduction: German (Matricaria chamomilla L. and Shirazi (Matricaria recutita L. chamomiles are the most important medicinal plants of the Astraceae family which are used in the pharmaceutical, health, food and cosmetics industries. Production of this plant has been undertaken in Iran mainly in Isfahan, Kohgiluyeh and Boyerahmad, Golestan and Hamedan provinces. In vitro propagation of plants have higher potential to produce qualified natural products, restoring and preserving of endangered plants, induction of somaclonal variation, industrial reproduction, valuable secondary metabolites and increased active ingredients. Researchers reported successful micropropagation system for five chamomile varieties on MS medium contained 0.01 mg/l NAA and 2.5 mg/l kinetin. The aim of this study was to investigate the effects of stem (with and without node, leaf and cotyledon explants and different plant growth regulators on direct regeneration of German and Shirazi chamomiles. Although the Shirazi chamomile is native to Iran, but German chamomile is Iran non-indigenous cultivar. By our knowledge, there have been no comparison reports about responses of these cultivars to tissue culture. Materials and Methods: This research was performed in the central laboratory of Agriculture Faculty in Yasouj University. Seeds were provided from Pakan-Bazr institute, Isfahan. Chamomile seeds were disinfected by ethanol (70% for 5-10 min and sodium hypocholorite 3% for 5-12 min and then washed for several times by distilled water. Then, seeds were sown on MS medium for germination. After 2-3 weeks, seedlings were grown and then planted in MS medium supplemented with hormonal combinations of NAA at two levels (0.1 and 0.5 mg/l, kinetin at three levels (2, 2.5 and 3 mg/l and Zeatin, BAP and 2ip at three levels (0.5, 1 and 1.5 mg/l. The experiment was performed in a completely randomized design with four replications. Factors included explants, cultivars and hormonal

Regenerating an Arsenic Removal Iron-Based Adsorptive ...

Science.gov (United States)

The replacement of exhausted, adsorptive media used to remove arsenic from drinking water accounts for approximately 80% of the total operational and maintenance (O/M) costs of this commonly used small system technology. The results of three, full scale system studies of an on-site media regeneration process (Part 1) showed it to be effective in stripping arsenic and other contaminants from the exhausted media. Part 2, of this two part paper, presents information on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement. The results of the studies indicate that regenerated media is very effective in removing arsenic and the regeneration cost is substantially less than the media replacement cost. On site regeneration, therefore, provides small systems with alternative to media replacement when removing arsenic from drinking water using adsorptive media technology. Part 2 of a two part paper on the performance of the regenerated media to remove arsenic through multiple regeneration cycles (3) and the approximate cost savings of regeneration over media replacement.

Clonal fidelity of chrysanthemum regenerated from long term cultures

Directory of Open Access Journals (Sweden)

Jevremović Slađana

2006-01-01

Full Text Available Morphological characteristics of flowers of long term regenerated chrysanthemum, cv. "White Spider", after ten years of micropropagation are investigated. Shoot cultures are established and maintained more than ten years by stem segment culture on MS medium supplemented with BAP and NAA (1.0, 0.1 mgL-1, respectively. Rooting of shoots (100 % has done on MS medium without hormones and it was very successful after ten years, as well as, after two or eight years of micropropagation. Acclimation of rooted chrysanthemum plantlets at greenhouse conditions was excellent and after appropriate photoperiod "in vitro" plants flowered 90.3 % and have the same flower color, shape and size as mother plants. Flower color changes of "in vitro" plants are observed during another flowering cycle one year after acclimatization. Observed variations of chrysanthemum flowers could be attributed to epigenetic factors.

In vitro micropropagation of Dracaena sanderiana Sander ex Mast: An important indoor ornamental plant.

Science.gov (United States)

Aslam, Junaid; Mujib, Abdul; Sharma, Maheshwar Prasad

2013-01-01

A protocol has been developed for in vitro plant regeneration from a nodal explant of Dracaena sanderiana Sander ex Mast. Nodal explant showed high callus induction potentiality on MS medium supplemented with 6.78 μM 2,4-dichlorophenoxyacetic acid (2,4-D) followed by 46.5 μM chlorophenoxy acetic acid (CPA). The highest frequency of shoot regeneration (85%) and number of shoots per explant (5.6) were obtained on medium supplemented with 7.84 μM N(6)-benzylaminopurine (BA). Rooting was high on MS solid compared to liquid medium when added with 7.38 μM indole-3-butyric acid (IBA). Fifty percent of the roots were also directly rooted as microcuttings on soil rite, sand and peat mixture (1:1:1). In vitro and ex vitro raised plantlets were used for acclimatization. More than 90% of the plantlets was successfully acclimatized and established in plastic pots. Ex vitro transferred plantlets were normal without any phenotypic aberrations.

Improvement of ISI techniques by multi-frequency eddy current testing method for steam generator tube in PWR plant

International Nuclear Information System (INIS)

Endo, Takashi; Kamimura, Takeo; Nishihara, Masatoshi; Araki, Yasuo; Fukui, Shigetaka.

1982-05-01

Eddy current flaw detection techniques are applied to the in-service inspection (ISI) of steam generator tubes in pressurized water reactors (PWR) plant. To improve the reliability and operating efficiency of the plants, efforts are being made to develop eddy current testing methods of various kinds. Multi-frequency eddy current testing method, one of new method, has recently been applied to actual heat exchanger tubes, contributing to the improvement of the detectability and signal evaluation of the ISI. The outline of multi-frequency eddy current testing method and its effects on the improvement of flaw detecting and signal evaluation accuracy are described. (author)

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

International Nuclear Information System (INIS)

Lehner, J.; Lin, C.C.; Pratt, W.T.; Su, T.; Danziger, L.

1995-01-01

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

[Regeneration of the ciliary beat of human ciliated cells].

Science.gov (United States)

Wolf, G; Koidl, B; Pelzmann, B

1991-10-01

The influence of an isotonic, alkaline saline solution (diluted "Emser Sole" or brine from the spa of Bad Ems) on the ciliary beat of isolated cultured human ciliated cells of the upper respiratory tract was investigated. The ciliary beat was observed via an inverted phase contrast microscope (Zeiss Axiomat IDPC) and measured microphotometrically under physiological conditions and after the damaging influence of 1% propanal solution. Under physiological conditions the saline solution had a positive, although statistically not significant influence on the frequency of the ciliary beat. After damage of the cultivated cells by 1% propanal solution, the saline solution had a significant better influence on the regeneration of the cultured cells than a physiological sodium chloride solution. It is concluded that diluted brine from Bad Ems has a positive effect on the ciliary beat of the respiratory epithelium and accelerates its regeneration after damage by viral and bacterial infections, surgery or inhaled noxae.

Skeletal muscle regeneration is modulated by inflammation

Directory of Open Access Journals (Sweden)

Wenjun Yang

2018-04-01

Full Text Available Skeletal muscle regeneration is a complex process orchestrated by multiple steps. Recent findings indicate that inflammatory responses could play central roles in bridging initial muscle injury responses and timely muscle injury reparation. The various types of immune cells and cytokines have crucial roles in muscle regeneration process. In this review, we briefly summarise the functions of acute inflammation in muscle regeneration. The translational potential of this article: Immune system is closely relevant to the muscle regeneration. Understanding the mechanisms of inflammation in muscle regeneration is therefore critical for the development of effective regenerative, and therapeutic strategies in muscular disorders. This review provides information for muscle regeneration research regarding the effects of inflammation on muscle regeneration. Keywords: Chronic muscle disorders, Cytokines, Immune cells, Inflammation, Muscle regeneration, Muscle stem cells

Divergent regeneration-competent cells adopt a common mechanism for callus initiation in angiosperms.

Science.gov (United States)

Hu, Bo; Zhang, Guifang; Liu, Wu; Shi, Jianmin; Wang, Hua; Qi, Meifang; Li, Jiqin; Qin, Peng; Ruan, Ying; Huang, Hai; Zhang, Yijing; Xu, Lin

2017-06-01

In tissue culture, the formation of callus from detached explants is a key step in plant regeneration; however, the regenerative abilities in different species are variable. While nearly all parts of organs of the dicot Arabidopsis thaliana are ready for callus formation, mature regions of organs in monocot rice ( Oryza sativa ) and other cereals are extremely unresponsive to tissue culture. Whether there is a common molecular mechanism beyond these different regenerative phenomena is unclear. Here we show that the Arabidopsis and rice use different regeneration-competent cells to initiate callus, whereas the cells all adopt WUSCHEL-RELATED HOMEOBOX 11 ( WOX11 ) and WOX5 during cell fate transition. Different from Arabidopsis which maintains regeneration-competent cells in mature organs, rice exhausts those cells during organ maturation, resulting in regenerative inability in mature organs. Our study not only explains this old perplexity in agricultural biotechnology, but also provides common molecular markers for tissue culture of different angiosperm species.

Pollutant emissions from vehicles with regenerating after-treatment systems in regulatory and real-world driving cycles.

Science.gov (United States)

Alvarez, Robert; Weilenmann, Martin; Novak, Philippe

2008-07-15

Regenerating exhaust after-treatment systems are increasingly employed in passenger cars in order to comply with regulatory emission standards. These systems include pollutant storage units that occasionally have to be regenerated. The regeneration strategy applied, the resultant emission levels and their share of the emission level during normal operation mode are key issues in determining realistic overall emission factors for these cars. In order to investigate these topics, test series with four cars featuring different types of such after-treatment systems were carried out. The emission performance in legislative and real-world cycles was monitored as well as at constant speeds. The extra emissions determined during regeneration stages are presented together with the methodology applied to calculate their impact on overall emissions. It can be concluded that exhaust after-treatment systems with storage units cause substantial overall extra emissions during regeneration mode and can appreciably affect the emission factors of cars equipped with such systems, depending on the frequency of regenerations. Considering that the fleet appearance of vehicles equipped with such after-treatment systems will increase due to the evolution of statutory pollutant emission levels, extra emissions originating from regenerations of pollutant storage units consequently need to be taken into account for fleet emission inventories. Accurately quantifying these extra emissions is achieved by either conducting sufficient repetitions of emission measurements with an individual car or by considerably increasing the size of the sample of cars with comparable after-treatment systems.

Electrical Stimulation to Enhance Axon Regeneration After Peripheral Nerve Injuries in Animal Models and Humans.

Science.gov (United States)

Gordon, Tessa

2016-04-01

Injured peripheral nerves regenerate their lost axons but functional recovery in humans is frequently disappointing. This is so particularly when injuries require regeneration over long distances and/or over long time periods. Fat replacement of chronically denervated muscles, a commonly accepted explanation, does not account for poor functional recovery. Rather, the basis for the poor nerve regeneration is the transient expression of growth-associated genes that accounts for declining regenerative capacity of neurons and the regenerative support of Schwann cells over time. Brief low-frequency electrical stimulation accelerates motor and sensory axon outgrowth across injury sites that, even after delayed surgical repair of injured nerves in animal models and patients, enhances nerve regeneration and target reinnervation. The stimulation elevates neuronal cyclic adenosine monophosphate and, in turn, the expression of neurotrophic factors and other growth-associated genes, including cytoskeletal proteins. Electrical stimulation of denervated muscles immediately after nerve transection and surgical repair also accelerates muscle reinnervation but, at this time, how the daily requirement of long-duration electrical pulses can be delivered to muscles remains a practical issue prior to translation to patients. Finally, the technique of inserting autologous nerve grafts that bridge between a donor nerve and an adjacent recipient denervated nerve stump significantly improves nerve regeneration after delayed nerve repair, the donor nerves sustaining the capacity of the denervated Schwann cells to support nerve regeneration. These reviewed methods to promote nerve regeneration and, in turn, to enhance functional recovery after nerve injury and surgical repair are sufficiently promising for early translation to the clinic.

Effect of plant growth regulators on callus induction and plant ...

African Journals Online (AJOL)

The present study was conducted to investigate the effects of different concentrations and combinations of growth regulators on callus induction and plant regeneration of potato (Solanum tuberosum L.) cultivar Diamant. The tuber segments were used as explants and cultured on Murashige and Skoog (MS) medium ...

Functional hepatocellular regeneration measured by hepatobiliary scintigraphy, functional regeneration or functional hepatocytes?

NARCIS (Netherlands)

Olthof, Pim B.; Cieslak, Kasia P.; Bennink, Roelof J.; van Gulik, Thomas M.

2016-01-01

In a recent issue of this journal, Fernandes et al(1) reported on functional hepatocellular regeneration in elderly patients undergoing hepatectomy. They used (99m) Tc-mebrofinin HBS to quantify liver function before and after surgery and concluded that functional regeneration is already present at

Micropropagation of Ficus religiosa L. via leaf explants and comparative evaluation of acetylcholinesterase inhibitory activity in the micropropagated and conventionally grown plants.

Science.gov (United States)

Siwach, Priyanka; Gill, Anita Rani

2014-10-01

A high-frequency, season-independent, in vitro regeneration of Ficusreligiosa was developed, followed by comparative acetylcholinesterase inhibitory (AChEI) activity assay of the in vitro raised and conventionally grown plants. The use of AChEI activity is the most accepted strategy for the treatment of Alzheimer disease. Fully expanded, mature leaves were cut into different segments to initiate the cultures. The middle section of the leaf in vertical orientation with cut portion inserted inside the medium was found most suitable for direct shoot regeneration. Leaf explants responded with nearly consistent frequency (60-66.67 %) throughout the year. To obtain high frequency response with enhanced shoot multiplication rate, 32 plant growth regulator regimes were screened amongst which benzylaminopurine at 5.0 mg/l was found most suitable, yielding 100 % response and maximum number of shoots per explant (7.93); same concentration was also most supportive for repeated multiplication (6.53 shoots). The quality of the shoots and multiplication rate could be significantly enhanced (24.35 shoots) when adenine sulphate, glutamine and phloroglucinol, in an optimised concentration, were additionally supplemented. The clonal nature of the micropropagated plants was confirmed by random amplified polymorphic DNA analysis. A comparative analysis of AChEI activity was carried out amongst the methanolic extracts of stem segments of the mother plant, randomly selected seedlings of different age (4 and 6 months old) of the same mother plant and randomly selected micropropagated plants of different age (3 and 6 months age). The mother plant sample showed effective AChEI activity, with IC 50 of 66.46 μg/ml while seedlings, of different age groups, performed poorly (6-month-old seedlings, Se-1 6M , yielded IC 50 of 20,538.46 μg/ml, while two randomly selected 4 months' aged seedlings, Se-2 4M and Se-3 4M exhibited IC 50 of 19,341.03 and 24,281.70 μg/ml). On the other hand

QPSK regeneration without active phase-locking

DEFF Research Database (Denmark)

Kjøller, Niels-Kristian; Da Ros, Francesco; Røge, Kasper Meldgaard

2016-01-01

QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal.......QPSK regeneration without active phase stabilization is investigated in numerical simulations. We propose an improved scheme for phase-locking free QPSK regeneration showing significant improvements in the error vector magnitude of the signal....

Biological regeneration of para-nitrophenol loaded activated carbon

International Nuclear Information System (INIS)

Durrani, M.A.Q.; Martin, R.J.

1997-01-01

Biological regeneration is one of several methods that may be used to restore the adsorptive capacity of exhausted granular activated carbon (GAC). This study deals with in-situ biological regeneration on a pilot scale. The principal objective of this research was to ascertain whether biological regeneration of GAC could occur under conditions typical of water treatment. The important parameters which may have the greatest impact on bio regeneration of a given adsorbate were studied. The research investigated the extent of bio regeneration for para-nitrophenol (PNP) of concentration 50 mg/L. Bio regeneration in the total exhaustion system was evaluated in terms of regeneration efficiency and the substrate removal. A three mode procedure was followed for each bio regeneration run. The prepared carbon was initially exhausted with an adsorbate; it was then bio regenerated for para-nitrophenol (PNP) of concentration 50 mg/L. Bio regeneration in he total exhaustion system was evaluated in terms of regeneration efficiency and the substrate removal. A three mode procedure was followed for each bio regeneration run. The prepared carbon was initially exhausted with an adsorbate; it was then bio regenerated with a mixed culture of bacteria, and lastly the carbon was re-saturated. In the totally exhausted GAC system, the bio regeneration was enhanced by increasing the during of regeneration for a fixed initial biomass content of the bioreactor. The bio regeneration efficiency of the totally exhausted (with PNP) GAC the empty bed contact time (EBCT) and the initial concentration of the substrate had a profound effect on the bio regeneration efficiency. Bacterial counts in the effluents of regenerated GAC columns were significantly more than those of fresh carbon effluents. (author)

In vitro shoot regeneration and microcorm development in crocus vernus (l.) hill

International Nuclear Information System (INIS)

Sivanesan, I.

2014-01-01

An efficient method has been developed for In vitro regeneration of shoot and microcorm from corm explants of Crocus vernus. Corms were cut into 0.5-1.0 cm long segments and cultured on the SH medium supplemented with 0.5, 1.0, 2.0, or 4.0 mg L-1 2-isopentyl adenine (2-iP), N6-benzyladenine (BA), and N6-furfuryladenine (kinetin, Kin) alone or combination with 0.5 or 1.0 mg L-1 alpha-naphthalene acetic acid (NAA) for shoot regeneration. Of the three cytokinins tested, BA was found to be the most effective cytokinin for shoot formation. The number of shoots induced per explant was more when BA was combined with 0.5 mg L-1 NAA than with 1.0 mg L-1 NAA. The greatest percentage of shoot induction (97.2) with the mean number of 11.8 shoots per explant was obtained when the SH medium was supplemented with 2.0 mg L-1 BA and 0.5 mg L-1 NAA. The frequency of microcorm induction was significantly affected by the concentrations of sucrose.The greatest number of 6.1 microcorms per explant was obtained when the SH medium was supplemented with 2.0 mg L-1 BA, 0.5 mg L-1 NAA and 6.0% sucrose. The microcorms formed In vitro developed daughter corms when they were cultured on this medium. Microcorms were separated from the culture and planted out in acclimatization boxes containing a commercial medium. About 85% of corms developed shoot and root after 30 days. This protocol could be utilized for genetic transformation and mass clonal propagation of C. (author)

On the reasons that natural regeneration is important for species coexistence in tropical forests

Directory of Open Access Journals (Sweden)

Natalia Norden

2014-12-01

Full Text Available Plant regeneration plays a critical role in the maintenance of species diversity in tropical rainforests. This is a multistage process, including seed production, dispersal, germination and subsequent seedling establishment. All these stages represent major bottlenecks in plant demography, as early stages in the plant cycle (seeds and seedlings are the most vulnerable to environmental hazards, and are therefore subject to high mortality risks. The outcome of these ecological filters will determine not only seedling spatial distribution, but also the potential area of tree distribution. Seed dispersal and subsequent seedling establishment therefore play a critical role in the structuring of tree communities. Here, I review the main four ecological processes driving seedling recruitment in tropical forests. First, dispersal limitation is the failure of seeds to reach suitable microsites for seedling establishment. Once this filter is overcome, environmental factors can considerably affect seedling spatial distribution. Temporal fluctuations in these processes result in an important variation in recruitment success over time, and add a stochastic component to seedling regeneration. Finally, negative-density dependence regulates species relative abundance in the seedling layer by limiting conspecific recruitment through the attack of pathogen, fungi and herbivores.

The blastema and epimorphic regeneration in mammals.

Science.gov (United States)

Seifert, Ashley W; Muneoka, Ken

2018-01-15

Studying regeneration in animals where and when it occurs is inherently interesting and a challenging research topic within developmental biology. Historically, vertebrate regeneration has been investigated in animals that display enhanced regenerative abilities and we have learned much from studying organ regeneration in amphibians and fish. From an applied perspective, while regeneration biologists will undoubtedly continue to study poikilothermic animals (i.e., amphibians and fish), studies focused on homeotherms (i.e., mammals and birds) are also necessary to advance regeneration biology. Emerging mammalian models of epimorphic regeneration are poised to help link regenerative biology and regenerative medicine. The regenerating rodent digit tip, which parallels human fingertip regeneration, and the regeneration of large circular defects through the ear pinna in spiny mice and rabbits, provide tractable, experimental systems where complex tissue structures are regrown through blastema formation and morphogenesis. Using these models as examples, we detail similarities and differences between the mammalian blastema and its classical counterpart to arrive at a broad working definition of a vertebrate regeneration blastema. This comparison leads us to conclude that regenerative failure is not related to the availability of regeneration-competent progenitor cells, but is most likely a function of the cellular response to the microenvironment that forms following traumatic injury. Recent studies demonstrating that targeted modification of this microenvironment can restrict or enhance regenerative capabilities in mammals helps provide a roadmap for eventually pushing the limits of human regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

DNA Methylation and Methylation Polymorphism in Genetically Stable In vitro Regenerates of Jatropha curcas L. Using Methylation-Sensitive AFLP Markers.