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 ...

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)

High efficiency indirect shoot regeneration and hypericin content in ...

African Journals Online (AJOL)

USER

2010-04-12

Apr 12, 2010 ... opium poppy. Support of hormone-free medium on shoot regeneration from callus has also been underlined for sugarbeet (Doley and Saunders, 1989). In our study, obtained regenerants acclimatized readily, alived (94%) and are still continuing to grow in the greenhouse of our department. Cell or callus ...

Cytokinin induced shoot regeneration and flowering of Scoparia dulcis L. (Scrophulariaceae)-an ethnomedicinal herb.

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Premkumar, G; Sankaranarayanan, R; Jeeva, S; Rajarathinam, K

2011-06-01

To develop an improved protocol for micropropagation of ethnomedicinally important Scoparia dulcis (S. dulcis) L. Explants were inoculated on MS basal medium supplemented with kinetin and 6-benzylaminopurine for shoot bud induction. To enhance the shoot induction, various auxins like 3-indoleacetic acid or 3-indolebutyric acid or α-naphthylacetic acid were tested along with 2.32 M KI and 4.44 µM BAP. The regenerated shoots were rooted in half strength MS medium supplemented with various concentrations of IAA, IBA or NAA. After roots were developed, the plantlets were transplanted to pots filled with vermiculate and sand and kept in growth chamber with 70%-80% humidity under 16 h photoperiod. After acclimatization, the plantlets were transferred to the garden and survival percentage was calculated. Data were statistically analyzed and means were compared using Duncan's multiple range test (Pdulcis. Shoot induction on young leaf explants was most successful in MS medium supplemented with combination of two cytokinins (2.32 µM KI and 4.44 µM BAP) 2.85 µM IAA, 10% CM and 1 483.79 µM adenine sulfate. A single young leaf explant was capable of producing 59 shoots after 13 days of culture. Flower was induced in medium supplemented with combination of KI and BAP. Cytokinins are the key factor to induce the direct shoot regeneration and flowering of S. dulcis.

Effects of gamma-rays irradiation in seed of mungbean (vigna radiata (L.) wilczek) composition of media on shoot regeneration of explants from node of cotyledon

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Hutabarat, Dameria; H, Soeranto

1998-01-01

Study the effects of gamma-rays irradiation and composition and media on shoot regeneration of explants from node of cotyledon of mungbean. Wallet variety have been conducted. The explants derived of irradiated seeds of 10-20 Gy of gamma rays were planted in the 0.7% agar solution. One day after planting in the agar media the embryo axis of germinate seed were removed and the node of cotyledon were cultured in the regeneration media as examples. The results shown that shoot regeneration was influenced by media composition and the doses of gamma rays irradiation in seed. In the MURASHIGE and SKOOG medium which contain of BAP or 2-iP or Kinetin with 3 ppm concentrate respectively the explants could produced 100% of shoots. However, the highest. number of produced shoot (3 shoots) was showed in the medium which contained of BAP. The medium with I ppm concentrate od BAP could produced 100% shoot regeneration and the maximum number of shoots (4 shoots) per explant was showed in with 5 ppm. concentrate of BAP. The effectivity off BAP for shoot regeneration by enrichment of 12 ppm Ag 2 SO 4 in the media. Irradiation of 10-20 Gy gamma rays on seeds of mungbean walet variety could improved shoot regeneration of explants from node cotyledon. (author)

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.

thidiazuron improves adventitious bud and shoot regeneration

African Journals Online (AJOL)

Prof. Adipala Ekwamu

Induction of adventitious buds and shoots from intact leaves and stem internode segments of two recalcitrant. Ugandan sweetpotato (Ipomoea batatas L.) cultivars was investigated in vitro on Murashige and Skoog (MS) medium, supplemented with 3 different levels (0.5, 2.0 and 4.0 µM) of Thidiazuron (TDZ). Shoots were.

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

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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 ...

Improved recovery of cryotherapy-treated shoot tips following thermotherapy of in vitro-grown stock shoots of raspberry (Rubus idaeus L.).

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Wang, Qiaochun; Valkonen, Jari P T

2009-01-01

Raspberry bushy dwarf virus (RBDV) can be efficiently eradicated from raspberry plants (Rubus idaeus) by a procedure combining thermotherapy and cryotherapy. However, the bottleneck of this procedure is that, following thermotherapy, cryopreserved shoot tips become chlorotic during regrowth and eventually die after several subcultures. In addition, survival of heat-treated stock shoots and recovery of cryopreserved shoot tips following thermotherapy are low. The present study focused towards improving regrowth of cryopreserved raspberry shoot tips following thermotherapy. Results showed that preconditioning stock shoots with salicylic acid (SA; 0.01-0.1 mM) markedly increased survival of stock shoots after 4 weeks of thermotherapy. Regrowth of cryopreserved shoot tips following thermotherapy was also significantly enhanced when SA (0.05-0.1 mM) was used for preconditioning stock shoots. Addition of either Fe-ethylenediaminetetracetic acid (Fe-EDTA, 50 mg per L) or Fe-ethylenediaminedi(o)hydroxyphenylacetic acid (Fe-EDDHA, 50 mg per L) to post-culture medium strongly promoted regrowth and totally prevented chlorosis of shoots regenerated from cryopreserved shoot tips following thermotherapy. Using the parameters optimized in the present study, about 80 percent survival of heat-treated stock shoots and about 33 percent regrowth of cryopreserved shoot tips following thermotherapy were obtained. Morphology of plants regenerated from cryopreserved shoot tips following thermotherapy was identical to that of control plants, based on observations of leaf shape and size, internode length and plant height. Optimization of the thermotherapy procedure followed by cryotherapy will facilitate the wider application of this technique to eliminate viruses which can invade meristems.

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

African Journals Online (AJOL)

The objective of this study was to develop an efficient protocol for adventitious shoot regeneration for Plectranthus barbatus Andrews using leaf explants. The explants were cultured on MS (Murashige and Skoog, 1962) medium containing various concentration of kinetin (KN), 6-benzylaminopurine (BAP) and thidiazuron ...

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 ...

The effect of tomato juices and bean sprout extracts on vitro shoot regeneration of Physalis angulata L.

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Mastuti, Retno; Munawarti, Aminatun; Rosyidah, Mufidatur

2017-11-01

Physalis angulata L. (Ciplukan) which belongs to Solanaceae is an important medicinal plant. In vitro culture medium contains carbon source, inorganic substance, vitamins, and plant growth regulators. However, organic growth supplements have frequently been added to improve regeneration capability of explants. This study was conducted to observe the effect of tomato juices and extract bean sprout on shoot regeneration and multiplication of in vitro nodal explants. The explants were cultured on MS basal medium + 6-benzyl amino purine (BAP) 2 mg/L + indole-3-acetic acid (IAA) 0.05 mg/L with and without organic supplements. Tomato juices (T) 5, 7.5 and 10% or bean sprout extract (B) 1.25, 2.5, and 3.75% were added as natural organic supplements. Almost all explants have produced shoots one week after culture. After six weeks of culture maximum shoot number (12.5±3.9) was produced in medium MS + T5 while maximum shoot length (10.7 ± 0.7 cm) was obtained in medium MS + T 7.5. Medium T tends to produce more shoots than the medium B and medium control. This result indicates the potential of natural organic supplements for supporting Ciplukan propagation through in vitro culture.

Detection of sodium azide-induced mutagenicity in the regenerated shoots of artemisia annual L., using internal transcribed spacer (its) sequences of nrDNA

International Nuclear Information System (INIS)

Al-Qurainy, F.; Al-Hemaidi, F.M.; Khan, S.; Ali, M.A.; Tarroum, M.; Ashraf, M.

2011-01-01

Sodium azide (NaN/sub 3/) is a well known chemical mutagen which can effectively cause point mutation in plant genome. The mutagenicity by this potential mutagen was assessed in the regenerated mutant shoots of Artemisia annua using internal transcribed spacer (ITS) sequences of n rDNA. Insertions and/or deletions were detected in n rDNA-ITS sequences of all mutant shoots and compared with control ones using the ClustalX program. The regenerated shoots TS1 and TS2 had deleted bases, whereas TS3, TS4 and TS5 had insertions, because NaN/sub 3/ replaced the cytosine (C) by thymine (T) (C - T) (shoots; TS1 and TS4) and thymine (T) replaced by guanine (G) (T - G) (shoot; TS5), respectively. Artemisinin content was also measured in the regenerated six-week-old shoots of A. annua. All regenerated shoots had enhanced level of this compound as compared to that in the controls, being highest in the regenerated shoot TS3. (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)

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

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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.

Regeneration of multiple shoots from transgenic potato events facilitates the recovery of phenotypically normal lines: assessing a cry9Aa2 gene conferring insect resistance

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Jacobs Jeanne ME

2011-10-01

Full Text Available Abstract Background The recovery of high performing transgenic lines in clonal crops is limited by the occurrence of somaclonal variation during the tissue culture phase of transformation. This is usually circumvented by developing large populations of transgenic lines, each derived from the first shoot to regenerate from each transformation event. This study investigates a new strategy of assessing multiple shoots independently regenerated from different transformed cell colonies of potato (Solanum tuberosum L.. Results A modified cry9Aa2 gene, under the transcriptional control of the CaMV 35S promoter, was transformed into four potato cultivars using Agrobacterium-mediated gene transfer using a nptII gene conferring kanamycin resistance as a selectable marker gene. Following gene transfer, 291 transgenic lines were grown in greenhouse experiments to assess somaclonal variation and resistance to potato tuber moth (PTM, Phthorimaea operculella (Zeller. Independently regenerated lines were recovered from many transformed cell colonies and Southern analysis confirmed whether they were derived from the same transformed cell. Multiple lines regenerated from the same transformed cell exhibited a similar response to PTM, but frequently exhibited a markedly different spectrum of somaclonal variation. Conclusions A new strategy for the genetic improvement of clonal crops involves the regeneration and evaluation of multiple shoots from each transformation event to facilitate the recovery of phenotypically normal transgenic lines. Most importantly, regenerated lines exhibiting the phenotypic appearance most similar to the parental cultivar are not necessarily derived from the first shoot regenerated from a transformed cell colony, but can frequently be a later regeneration event.

Improving adventitious shoot regeneration from cultured leaf ...

African Journals Online (AJOL)

The effect of various concentrations of thidiazuron (TDZ) with or without 2.7 μM of α-naphthalene acetic acid (NAA) on adventitious shoot formation of two Petunia hybrida cultivars was studied. Seeds from 'Daddy Blue' and 'Dreams White' cultivars were germinated in vitro. Expanded leaves from both seedlings and ...

The effect of sodium hypochlorite solutions on in vitro seedling growth and shoot regeneration of flax (Linum usitatissimum)

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Yildiz, Mustafa; Er, Celâl

2002-04-01

The aim of this study was to determine the effect of concentration (40, 60, and 80%) and temperature (0, 10, 20, and 30°C) of sodium hypochlorite (NaOCl) solutions on seed germination, in vitro viability and growth of flax seedlings and regeneration capacity of hypocotyl explants. Results showed that seed germination, seedling growth and shoot regeneration were negatively affected by increasing concentration and temperature of disinfectant. The best results in seedling growth and shoot regeneration were obtained when 40% disinfectant concentration at 10°C was used.

Transcriptomic and Hormonal Analyses Reveal that YUC-Mediated Auxin Biogenesis Is Involved in Shoot Regeneration from Rhizome in Cymbidium.

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Liu, Yang; Zhang, Hai-Liang; Guo, He-Rong; Xie, Li; Zeng, Rui-Zhen; Zhang, Xiang-Qian; Zhang, Zhi-Sheng

2017-01-01

Cymbidium , one of the most important orchid genera in horticulture, can be classified into epiphytic and terrestrial species. Generally, epiphytic Cymbidium seedlings can be easily propagated by tissue culture, but terrestrial seedlings are difficult to propagate. To date, the molecular mechanisms underlying the differences in the ease with which terrestrial and epiphytic cymbidiums can be propagated are largely unknown. Using RNA-sequencing, quantitative reverse transcription PCR and enzyme-linked immunosorbent assay, Cymbidium 'Xiaofeng' (CXF), which can be efficiently micropropagated, and terrestrial Cymbidium sinense 'Qijianbaimo' (CSQ), which has a low regeneration ability, were used to explore the molecular mechanisms underlying the micropropagation ability of Cymbidium species. To this end, 447 million clean short reads were generated, and 31,264 annotated unigenes were obtained from 10 cDNA libraries. A total of 1,290 differentially expressed genes (DEGs) were identified between CXF and CSQ during shoot induction. Gene ontology (GO) enrichment analysis indicated that the DEGs were significantly enriched in auxin pathway-related GO terms. Further analysis demonstrated that YUC and GH3 family genes, which play crucial roles in the regulation of auxin/IAA (indole-3-acetic acid) metabolism, acted quickly in response to shoot induction culture in vitro and were closely correlated with variation in shoot regeneration between CXF and CSQ. In addition, the study showed that IAA accumulated rapidly and significantly during shoot induction in CXF compared to that in CSQ; in contrast, no significant changes in other hormones were observed between CXF and CSQ. Furthermore, shoot regeneration in CXF was inhibited by a yucasin-auxin biosynthesis inhibitor, indicating that increased IAA level is required for high-frequency shoot regeneration in CXF. In conclusion, our study revealed that YUC-mediated auxin biogenesis is involved in shoot regeneration from rhizome in

Transcriptomic and Hormonal Analyses Reveal that YUC-Mediated Auxin Biogenesis Is Involved in Shoot Regeneration from Rhizome in Cymbidium

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Yang Liu

2017-10-01

Full Text Available Cymbidium, one of the most important orchid genera in horticulture, can be classified into epiphytic and terrestrial species. Generally, epiphytic Cymbidium seedlings can be easily propagated by tissue culture, but terrestrial seedlings are difficult to propagate. To date, the molecular mechanisms underlying the differences in the ease with which terrestrial and epiphytic cymbidiums can be propagated are largely unknown. Using RNA-sequencing, quantitative reverse transcription PCR and enzyme-linked immunosorbent assay, Cymbidium ‘Xiaofeng’ (CXF, which can be efficiently micropropagated, and terrestrial Cymbidium sinense ‘Qijianbaimo’ (CSQ, which has a low regeneration ability, were used to explore the molecular mechanisms underlying the micropropagation ability of Cymbidium species. To this end, 447 million clean short reads were generated, and 31,264 annotated unigenes were obtained from 10 cDNA libraries. A total of 1,290 differentially expressed genes (DEGs were identified between CXF and CSQ during shoot induction. Gene ontology (GO enrichment analysis indicated that the DEGs were significantly enriched in auxin pathway-related GO terms. Further analysis demonstrated that YUC and GH3 family genes, which play crucial roles in the regulation of auxin/IAA (indole-3-acetic acid metabolism, acted quickly in response to shoot induction culture in vitro and were closely correlated with variation in shoot regeneration between CXF and CSQ. In addition, the study showed that IAA accumulated rapidly and significantly during shoot induction in CXF compared to that in CSQ; in contrast, no significant changes in other hormones were observed between CXF and CSQ. Furthermore, shoot regeneration in CXF was inhibited by a yucasin-auxin biosynthesis inhibitor, indicating that increased IAA level is required for high-frequency shoot regeneration in CXF. In conclusion, our study revealed that YUC-mediated auxin biogenesis is involved in shoot

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)

Shoot regeneration of callus culture from irradiated sheed of piper nigrum L by gamma rays

International Nuclear Information System (INIS)

Ishak; Hutabarat, D.

1988-01-01

Shoot regeneration was obtained from callus that induced by irradiated seed with 25 and 50 Gy of gamma-rays and then on M.S. medium containing NAA 1 ppm and 2-ip 0.5 ppm. Irradiated seed with a dose of 25 Gy produced normal root and failed to produce shoot, but rice callus. Irradiated seed with a dose of 50 Gy pruduce callus only. Shoot differentiation occured after the callus were cultured on M.S., medium containing 2-ip 1 ppm and Kinetin 2.5 ppm. (authors). 9 refs, 3 figs

Effects of thidiazuron and paclobutrazol on regeneration potential of tulip flower stalk explants in vitro and subsequent shoot multiplication

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Małgorzata Podwyszyńska

2011-01-01

Full Text Available The effects of TDZ and paclobutrazol on the primary regeneration on tulip flower stalk explants of six cultivars and subsequent shoot multiplication were examined. Explants, flower stalk slices, were excised from cooled and subsequently forced bulbs. The explants were incubated for two months in darkness on medium containing NAA and cytokinins, 2iP and BAP, as control, or TDZ (0.5-4 mg l-1 and paclobutrazol (0.05-0.4 mg l-1. Then, the regenerating explants were subcultured on medium with TDZ and NAA applied at low concentrations. Different regeneration capabilities were found depending on cultivar and growth regulators. The percentage of explants forming leaf-like structures ranged, on the control medium, from 80% in 'Blue Parrot' and 'Prominence' to below 30% in 'Apeldoorn' and 'Mirjoran'. TDZ, applied at optimum for each cultivar concentration, greatly increased the regeneration potential up to 70-100%. Paclobutrazol, added to the TDZ-containing medium, significantly enhanced the response of explants, resulting in high numbers of leaf-like structures formed per explant (13.7-22.8. The structures developed gradually into characteristic forms: the growing up cotyledonary leaf, the probable root primordium formed at its base, the growing downwards stolon and the shoot meristem developed finely on its tip. It is suggested that such primary regeneration may have a nature of somatic embryogenesis. Then, the adventitious shoots developed and formed clusters, which were divided into 2-3 smaller ones every two months. The growth regulators, used at initial stage, markedly influenced subsequent shoot multiplication. Thus, the most intensive shoot formation was noted with TDZ at concentrations of 0.5-2 mg l-1 and paclobutrazol of 0.05-0.1 mg l-1.

Effects of GhWUS from upland cotton (Gossypium hirsutum L.) on somatic embryogenesis and shoot regeneration.

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Xiao, Yanqing; Chen, Yanli; Ding, Yanpeng; Wu, Jie; Wang, Peng; Yu, Ya; Wei, Xi; Wang, Ye; Zhang, Chaojun; Li, Fuguang; Ge, Xiaoyang

2018-05-01

The WUSCHEL (WUS) gene encodes a plant-specific homeodomain-containing transcriptional regulator, which plays important roles during embryogenesis, as well as in the formation of shoot and flower meristems. Here, we isolated two homologues of Arabidopsis thaliana WUS (AtWUS), GhWUS1a_At and GhWUS1b_At, from upland cotton (Gossypium hirsutum). Domain analysis suggested that the two putative GhWUS proteins contained a highly conserved DNA-binding HOX domain and a WUS-box. Expression profile analysis showed that GhWUSs were predominantly expressed during the embryoid stage. Ectopic expression of GhWUSs in Arabidopsis could induce somatic embryo and shoot formation from seedling root tips. Furthermore, in the absence of exogenous hormone, overexpression of GhWUSs in Arabidopsis could promote shoot regeneration from excised roots, and in the presence of exogenous auxin, excised roots expressing GhWUS could be induced to produce somatic embryo. In addition, expression of the chimeric GhWUS repressor in cotton callus inhibited embryogenic callus formation. Our results show that GhWUS is an important regulator of somatic embryogenesis and shoot regeneration. Copyright © 2018 Elsevier B.V. All rights reserved.

Improved regeneration and transformation protocols for three strawberry cultivars

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Zakaria, Hossam; Hussein, Gihan M; Abdel-Hadi, Abdel-Hadi A; Abdallah, Naglaa A

2014-01-01

Strawberry (Fragaria × ananassa) is an economically important soft fruit crop with polyploid genome which makes the breeding of new cultivars difficult. Simple and efficient method for transformation and regeneration is required for cultivars improvement in strawberry. In the present study, adventitious shoot regeneration has been investigated in three cultivated strawberry plants, i.e., Festival, Sweet Charly and Florida via direct organogenesis using the in vitro juvenile leaves as explants. Explants were collected after sub-culturing on a propagation medium composed of MS supplemented with 0.5 mg/l BA; 0.1 mg/l GA3 and 0.1 mg/l IBA. To select the suitable organogenesis, the explants of the three cultivars were cultured on MS medium supplemented with different concentrations of TDZ (1, 2, 3, and 4 mg/l), then incubated at a temperature of 22 °C ± 2. Medium containing 2 mg/l TDZ revealed the best regeneration efficiency with the three cultivars (72% for Festival, and 73% for Sweet Charly and Florida). After 4 weeks, the produced shoots were cultured on MS medium with different concentrations of BA and Kin to enhance shoot elongation. Results showed that the medium containing 1.5 mg/l BA and 0.5 mg/l Kin revealed highest elongation efficiency (88% and 94%) for Festival and Sweet Charly, respectively. On the other hand, medium containing 1.5 mg/l BA and 0.1 mg/l Kin showed highest elongation efficiency (90%) in Florida. Elongated shoots were successfully rooted on MS medium containing 1.5 mg/l NAA. Furthermore, transformation of the two cultivars, Festival and Sweet Charly, has been established via Agrobacterium strain LBA44404 containing the plasmid pISV2678 with gus-intron and bar genes. Three days post co-cultivation, GUS activity was screening using the histochemical assay. The results showed 16% and 18% of the tested plant materials has changed into blue color for Festival and Sweet Charly, respectively. Out of 120 explants only 13 shoots were developed on

In vtro adventitious shoot regeneration from cotyledon explant of brassica oleracea subsp. Italica and brassica oleracea subsp. capitata using tdz and naa

International Nuclear Information System (INIS)

Salim, S.; Rashid, A.

2014-01-01

Broccoli(Brassica oleracea subsp. italica) cv. Green Dragon King and cabbage (Brassica oleracea subsp. capitata) cv. Gianty are important vegetable crops grown in Cameron Highlands, Malaysia. The cotyledons of both cultivars were used as explant source for in vitro shoot regeneration. The objective of this research was to examine the influence of the growth regulators thidiazuron (TDZ) and naphthaleneacetic acid (NAA) on adventitious shoot formation in these cultivars. This system of adventitious shoot regeneration from cotyledon explants could be useful as a tool for genetic transformation of the subspecies. Cotyledon explants of both cultivars excised from 5-day-old in vitro germinated seedlings were placed on shoot induction medium containing basal salts of Murashige and Skoog (MS) and various concentrations of TDZ and NAA. The highest percentage of cotyledon explant of broccoli cv. Green Dragon King producing shoot (76.66%) and the highest mean number of shoots produced per explant (0.9) were obtained on 0.1 mg/l TDZ with 0.1 mg/l NAA. Meanwhile, the highest percentage of cotyledon explant of cabbage cv. Gianty producing shoots (86.67%) and highest number of shoots produced per explant (1.1) were recorded on 0.5 mg/l TDZ with 0.1 mg/l NAA. Therefore, 0.1 mg/l TDZ with 0.1 mg/l NAA and 0.5 mg/l TDZ with 0.1mg/l NAA are the recommended combinations for adventitious shoot regeneration from cotyledonary explants of broccoli cv. Dragon King and cabbage cv. Gianty respectively. (author)

Agrobacterium-mediated transformation of cotton (Gossypium hirsutum) shoot apex with a fungal phytase gene improves phosphorus acquisition.

Science.gov (United States)

Ma, Zhiying; Liu, Jianfeng; Wang, Xingfen

2013-01-01

Cotton is an important world economic crop plant. It is considered that cotton is recalcitrant to in vitro proliferation. Somatic embryogenesis and plant regeneration has been successful by using hypocotyl, whereas it is highly genotype dependent. Here, a genotype-independent cotton regeneration protocol from shoot apices is presented. Shoot apices from 3- to 5-day-old seedlings of cotton are infected with an Agrobacterium strain, EHA105, carrying the binary vector pC-KSA contained phytase gene (phyA) and the marker gene neomycin phosphotransferase (NPTII), and directly regenerated as shoots in vitro. Rooted shoots can be obtained within 6-8 weeks. Plants that survived by leaf painting kanamycin (kan) were -further analyzed by DNA and RNA blottings. The transgenic plants with increased the phosphorus (P) acquisition efficiency were obtained following the transformation method.

Effects of ion beam irradiation on adventitious shoot regeneration from in vitro leaf explants of Septennial ionahta

International Nuclear Information System (INIS)

Zhou, L.B.; Li, W.J.; Ma, S.; Dong, X.C.; Yu, L.X.; Li, Q.; Zhou, G.M.; Gao, Q.X.

2006-01-01

The effects of 960 MeV carbon ion beam and 8 MeV X-ray irradiation on adventitious shoots from in vitro leaf explants of two different Saintpaulia ionahta (Mauve and Indikon) cultivars were studied with regard to tissue increase, shoots differentiation and morphology changes in the shoots. The experimental results showed that the survival fraction of shoot formation for the Mauve and Indikon irradiated with the carbon ion beam at 20 Gy were 0.715 and 0.600, respectively, while those for both the cultivars exposed to the X-ray irradiation at the same dose were 1.000. Relative biological effectiveness (RBE) of Mauve with respect to X-ray was about two. Secondly, the percentage of regenerating explants with malformed shoots in all Mauve regenerating explants irradiated with carbon ion beam at 20 Gy accounted for 49.6%, while that irradiated with the same dose of X-ray irradiation was only 4.7%; as for Saintpaulia ionahta Indikon irradiated with 20 Gy carbon ion beam, the percentage was 43.3%, which was higher than that of X-ray irradiation. Last, many chlorophyll deficient and other varieties of mutants were obtained in this study. Based on the results above, it can be concluded that the effect of mutation induction by carbon ion beam irradiation on the leaf explants of Saintpaulia ionahta is better than that by X-ray irradiation; and the optimal mutagenic dose varies from 20 Gy to 25 Gy for carbon ion beam irradiation

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.

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

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

Directory of Open Access Journals (Sweden)

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

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.

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

In Vitro Regeneration of Shoots From Nodal Explants of Dendrobium Chrysotoxum Lindl

Directory of Open Access Journals (Sweden)

Kaur Saranjeet

2017-06-01

Full Text Available Transverse sections (2 mm thickness of stem-nodes from in vitro raised seedlings had morphogenic potential on semisolid and liquid Murashige and Skoog medium supplemented with cytokinins N6-benzyladenine (BA 4.44 μM, furfurylaminopurine (KIN 4.65 μM and auxin α-naphthalene acetic acid (NAA 5.37 μM individually and in combinations. The regeneration response was influenced by both the type of growth regulator and physical state of the medium. The explants produced either shoot buds on cytokinincontaining media or protocorm-like bodies (PLBs on NAA containing media both solid and liquid. More neo-formations were produced on liquid media, especially those containing only NAA. They were formed at nodal and inter-nodal regions. The secondary buds were produced on the surface of primary PLBs. The plantlets were developed on MS medium containing banana homogenate 50 g·dm-3. The current study is the first ever report on successful regeneration of Dendrobium chrysotoxum from stem-node segments.

Effect of lanthanum on rooting of in vitro regenerated shoots of Saussurea involucrata Kar. et Kir.

Science.gov (United States)

Guo, Bin; Xu, Ling-Ling; Guan, Zhen-Jun; Wei, Ya-Hui

2012-06-01

In present study, the effect of lanthanum (La) on the rooting of regenerated shoots of Saussurea involucrata Kar. et Kir was analyzed. Rooting occurred from regenerated shoots inoculated on a medium supplemented with La, the plant rooting hormone indole-3-acetic acid (IAA), or both La and IAA together. The highest rooting efficiency (96%), root number/shoot (8.5), and root length (63 mm) were recorded in shoots cultured on medium containing 2.5 μM IAA combined with 100 μM La(3+). In order to elucidate the mechanism of rooting enhancement by La, we examined dynamic changes in antioxidant enzyme activities in plant tissue over time in culture. We found that the activities of peroxidase (POX) and superoxide dismutase (SOD) were significantly higher in plant tissue cultured in IAA plus La than in La or IAA alone. At the same time, the highest H(2)O(2) content was detected in plant tissue in the presence of 2.5 μM IAA plus 100 μM La(3+). In light of these data and previous results, we speculate that La enhanced IAA-induced rooting by acting as a mild abiotic stress to stimulate POX and SOD activities in plant cells. Then, IAA reacted with oxygen and POX to form the ternary complex enzyme-IAA-O(2) that dissociated into IAA radicals and O(2)(-). Subsequently, IAA-induced O(2)(-) readily converted to hydroxyl radical (HO·) via SOD-catalyzed dismutation. Finally, cell wall loosening and cell elongation occurred as a consequence of HO-dependent scission of wall components, leading to root growth. The treatment of IAA combined with La resulted in the highest plantlet survival (80%) compared to single treatments with IAA or La alone. These data suggest that rare earth elements enhance root morphogenesis and the growth of S. involucrata.

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...

Multiple shoot regeneration of cotton (Gossypium hirsutum L.) via ...

African Journals Online (AJOL)

user

2011-03-14

Mar 14, 2011 ... Induction of multiple shoots of cotton (Gossypium hirsutum L.) plant in two commercial varieties (Sahel and Varamin) using shoot apex was done. Explants were isolated from 3 - 4 days old seedlings, then they were cultured on a shoot induction media, modified MS nutrient agar with combinations: 1- ...

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

Science.gov (United States)

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.

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)

Shoot and root morphogenesis from Eucalyptus grandis x urophylla ...

African Journals Online (AJOL)

Eucalyptus grandis x urophylla plantlets were regenerated via indirect organogenesis. Histological assessment of their development focused on identifying the calli, the differentiation of shoots from the calli and the shoot-root junction from the nascent shoots. Vascular tissue formation within the callus preceded that of ...

Shoot organogenesis in oleaster (Elaeagnus angustifolia L.)

African Journals Online (AJOL)

STORAGESEVER

2009-02-04

Feb 4, 2009 ... Regenerated plantlets were acclimatized and successfully transplanted to soil. Key words: shoot organogenesis, callus, ... saline and alkaline soils (Economou and Maloupa, 1995). Its fruits have been used as a .... cally inert compounds as reported by Kaminek (1992). Direct shoot organogenesis without ...

Plant regeneration of bananas Ambon kuning and Barangan mutant lines were carried out by using female organ and shoot-tip as explants source

International Nuclear Information System (INIS)

Dewi, Azri K; Ishak

1998-01-01

Plant regeneration of bananas Ambon Kuning and Barangan mutant lines were carried out by using female organ and shoot-tip as explants source. Female organ was taken from heart of banana stem, while shoot-tip taken from sucker in banana plantation at Pasar Jumat, Jakarta. Those explants were cultured on MS medium containing 3 mg/l BAP, 0.5 mg/l IAA and supplemented by 100 tyrosin and 80 mg/l adenin hemisulphate. Observation showed that 180 and 42 buds were obtained from JBR 02 mutant lines respectively, while 84 and 79 buds for JAK 01 and JAK 02 respectively. The highest shoot formation was 1.013 shoots were obtained from BRC variety and lowest one was JBR 01 mutant line. statistical data analysis indicated that shoot formation between BRC variety and another mutant lines were significant difference using LSD test at level 0.05. Plantlet formation derived from female organ as well as shoot-tip showed that BRC variety produced number of plantlets per bottle was higher that another one. (author)

In-vitro morphogenesis of corn (Zea mays L.) : I. Differentiation of multiple shoot clumps and somatic embryos from shoot tips.

Science.gov (United States)

Zhong, H; Srinivasan, C; Sticklen, M B

1992-07-01

In-vitro methods have been developed to regenerate clumps of multiple shoots and somatic embryos at high frequency from shoot tips of aseptically-grown seedlings as well as from shoot apices of precociously-germinated immature zygotic embryos of corn (Zea mays L.). About 500 shoots were produced from a shoot tip after eight weeks of culture (primary culture and one subculture of four weeks) in darkness on Murashige and Skoog basal medium (MS) supplemented with 500 mg/L casein hydrolysate (CH) and 9 μM N(6)-benzyladenine (BA). In this medium, shoots formed in shoot tips as tightly packed "multiple shoot clumps" (MSC), which were composed of some axillary shoots and many adventitious shoots. When the shoot tips were cultured on MS medium containing 500 mg/L CH, 9 μM BA and 2.25 μM 2,4-dichlorophenoxyacetic acid (2,4-D), most of the shoots in the clumps were adventitious in origin. Similar shoot tips cultured on MS medium containing 500 mg/L CH, 4.5 μM BA and 2.25 μM 2,4-D regenerated many somatic embryos within eight weeks of culture. Somatic embryos were produced either directly from the shoot apical meristems or from calli derived from the shoots apices. Both the MSC and the embryos produced normal shoots on MS medium containing 2.25 μM BA and 1.8 μM indole-3-butyric acid (IBA). These shoots were rooted on MS medium containing 3.6 μM IBA, and fertile corn plants were grown in the greenhouse. The sweet-corn genotype, Honey N Pearl, was used for the experiments described above, but shoot-tip cultures from all of 19 other corn genotypes tested also formed MSC on MS medium containing 500 mg/L CH and 9 μM BA.

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

Science.gov (United States)

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

2016-01-01

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

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

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)

Plant regeneration protocol of Andrographis paniculata (Burm. f ...

African Journals Online (AJOL)

Plant regeneration protocol of Andrographis paniculata (Burm. f.) - an important medicinal plant. ... Inclusion of 1.0 mg/l 1-naphthalene acetic acid (NAA) in the culture medium along with BA + Ads promoted a higher rate of shoot bud regeneration. Maximum mean number of shoot bud per explant (28.6) was achieved on the ...

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.

Direct adventitious shoot bud formation on hypocotyls explants in Millettia pinnata (L.) Panigrahi- a biodiesel producing medicinal tree species

OpenAIRE

Nagar, Durga Singh; Jha, Suman Kumar; Jani, Jigar

2015-01-01

A reproducible protocol developed for in vitro regeneration of Milletia pinnata using hypocotyl segments. Multiple shoots were induced from hypocotyl explants through direct adventitious shoot bud regeneration. The proximal end of hypocotyls was responsive for shoot bud induction. Silver nitrate and adenine sulphate had a positive effect on shoot bud induction and elongation. The maximum response and number of shoot bud produced in media supplemented with 8.88 μM BAP with 108.6 μM adenine sul...

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.

Optimization of in vitro regeneration and Agrobacterium tumefaciens-mediated transformation with heat-resistant cDNA in Brassica oleracea subsp. italica cv. Green Marvel.

Science.gov (United States)

Ravanfar, Seyed Ali; Aziz, Maheran Abdul; Saud, Halimi Mohd; Abdullah, Janna Ong

2015-11-01

An efficient system for shoot regeneration and Agrobacterium tumefaciens-mediated transformation of Brassica oleracea cv. Green Marvel cultivar is described. This study focuses on developing shoot regeneration from hypocotyl explants of broccoli cv. Green Marvel using thidiazuron (TDZ), zeatin, and kinetin, the optimization of factors affecting Agrobacterium-mediated transformation of the hypocotyl explants with heat-resistant cDNA, followed by the confirmation of transgenicity of the regenerants. High shoot regeneration was observed in 0.05-0.1 mg dm(-3) TDZ. TDZ at 0.1 mg dm(-3) produced among the highest percentage of shoot regeneration (96.67 %) and mean number of shoot formation (6.17). The highest percentage (13.33 %) and mean number (0.17) of putative transformant production were on hypocotyl explants subjected to preculture on shoot regeneration medium (SRM) with 200 µM acetosyringone. On optimization of bacterial density and inoculation time, the highest percentage and mean number of putative transformant production were on hypocotyl explants inoculated with a bacterial dilution of 1:5 for 30 min. Polymerase chain reaction (PCR) assay indicated a transformation efficiency of 8.33 %. The luciferase assay showed stable integration of the Arabidopsis thaliana HSP101 (AtHSP101) cDNA in the transgenic broccoli regenerants. Three out of five transgenic lines confirmed through PCR showed positive hybridization bands of the AtHSP101 cDNA through Southern blot analysis. The presence of AtHSP101 transcripts in the three transgenic broccoli lines indicated by reverse transcription-PCR (RT-PCR) confirmed the expression of the gene. In conclusion, an improved regeneration system has been established from hypocotyl explants of broccoli followed by successful transformation with AtHSP101 for resistance to high temperature.

Direct shoot organogenesis of Digitalis trojana Ivan., an endemic ...

African Journals Online (AJOL)

STORAGESEVER

2010-03-15

Mar 15, 2010 ... An efficient protocol for in vitro propagation of Digitalis trojana Ivan. was developed via adventitious shoot regeneration. Leaf explants were cultured on MS which were supplemented with different concentrations of NAA (0.1, 0.5, 1.0 mg/ml) and BAP (0.1, 0.5, 1.0, 3.0, 5.0 mg/ml) for shoot formation.

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)

In Vitro Regeneration of Foxtail Millet (Setaria italica (L. Beauv. cv. Buru Hotong

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Iriawati

2017-09-01

Full Text Available In vitro regeneration of foxtail millet (Setaria italica (L. Beauv. was done using basal shoot explants of 10-day old seedlings. Explants were cultured in MS basal medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D, kinetin, 6-benzylaminopurine (BAP and 1.5 ppm NiSO4. Shoot multiplication and root induction were done in Murashige and Skoog (MS basal media. Plantlets were then acclimatized in rice husk charcoal, cocopeat, or mixed media. Results showed that MS basal medium containing 0.5 ppm kinetin, 2 ppm BAP, and 0.1 ppm 2,4-D was the optimal medium for shoot induction, in which 60% of explants developed direct shoot organogenesis. In addition, callus was optimally formed in MS medium supplemented by 1 ppm kinetin, 1 ppm BAP, and 0.5 ppm 2,4-D. Regenerated shoots spontaneously developed roots after being transferred into MS basal media without growth regulator. During acclimatization, the highest survival rate of plantlets (47% was obtained in rice husk charcoal. The developed method could be useful towards improvement of this species using in vitro tissue culture techniques.

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.

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.

An evaluation of a new approach to the regeneration of Helichrysum italicum (Roth) G. Don, and the molecular characterization of the variation among sets of differently derived regenerants.

Science.gov (United States)

Perrini, Rosaria; Alba, Vittorio; Ruta, Claudia; Morone-Fortunato, Irene; Blanco, Antonio; Montemurro, Cinzia

2009-01-01

A protocol for the induction of regeneration from leaves of Helichrysum italicum was established. Calli were found to form on the basal medium only when it was supplemented with thidiazuron (TDZ) alone or in combination with naphthalene acetic acid (NAA), with a percentage ranking of at least 80%. The hormone-free medium showed the highest percentage of shoot regeneration (62%) even though no callus formed. AFLP markers were employed to verify tissue culture-induced variation in the regenerated plantlets obtained by direct shoot regeneration or the indirect shoot regeneration process (callus formation). Seven out of the eleven AFLP primer pairs yielded polymorphic patterns. The average number of fragments per primer pair was 64.1. Singletons were represented by 12 (2.7%) fragments. Student's T-test was performed both on the average number of shared fragments and on the nucleotide diversity, and no significant statistical difference was observed between the two regeneration treatments.

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...

Spine micromorphology of normal and hyperhydric Mammillaria gracilis Pfeiff. (Cactaceae) shoots.

Science.gov (United States)

Peharec, P; Posilović, H; Balen, B; Krsnik-Rasol, M

2010-07-01

Artificial conditions of tissue culture affect growth and physiology of crassulacean acid metabolism plants which often results in formation of hyperhydric shoots. In in vitro conditions Mammillaria gracilis Pfeiff. (Cactaceae) growth switches from organized to unorganized way, producing a habituated organogenic callus which simultaneously regenerates morphologically normal as well as altered hyperhydric shoots. In this study, influence of tissue culture conditions on morphology of cactus spines of normal and hyperhydric shoots was investigated. Spines of pot-grown Mammillaria plants and of in vitro regenerated shoots were examined with stereo microscope and scanning electron microscope. The pot-grown plants had 16-17 spines per areole. In vitro grown normal shoots, even though they kept typical shoot morphology, had lower number of spines (11-12) and altered spine morphology. This difference was even more pronounced in spine number (six to seven) and morphology of the hyperhydric shoots. Scanning electron microscopy analysis revealed remarkable differences in micromorphology of spine surface between pot-grown and in vitro grown shoots. Spines of in vitro grown normal shoots showed numerous long trichomes, which were more elongated on spines of the hyperhydric shoots; the corresponding structures on spine surface of pot-grown plants were noticed only as small protrusions. Scanning electron microscopy morphometric studies showed that the spines of pot-grown plants were significantly longer compared to the spines of shoots grown in tissue culture. Moreover, transverse section shape varies from elliptical in pot-grown plants to circular in normal and hyperhydric shoots grown in vitro. Cluster and correspondence analyses performed on the scanning electron microscope obtained results suggest great variability among spines of pot-grown plants. Spines of in vitro grown normal and hyperhydric shoots showed low level of morphological variation among themselves despite the

Regeneración de brotes adventicios en hojas de guayaba (Psidium guajava L. cultivadas in vitro Adventitious shoot regeneration from in vitro cultured leaves of guava (Psidium guava L.

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Trujillo Sánchez Reinaldo

2004-12-01

Full Text Available La regeneración de brotes adventicios es una etapa clave para la aplicación de las técnicas de ingeniería gené­tica. El presente trabajo tuvo como objetivo el desarrollo de un procedimiento para la regeneración de brotes por organogénesis a partir de hojas de microesquejes o brotes de guayaba (Psidium guajava L. cultivados in vi­tro. Para ello se estudiaron algunos de los principales factores que afectan la regeneración de brotes, tales como la concentración de reguladores del crecimiento (citoquinina, el estado fisiológico del explante y la he­rida. En todos los experimentos se utilizaron como explantes hojas de vitroplantas de guayaba de la variedad Enana Roja Cubana EEA18-40 de diferentes subcultivos. El mejor resultado se alcanzó con una concentración de 0,75 mg/L de 6-bencilaminopurina como suplemento hormonal del medio MS. Se comprobó que para las hojas provenientes de microesquejes con mayor número de subcultivo y tomadas de la parte inferior de los brotes, el potencial morfogenético disminuye significativamente (p60% y el mayor número de brotes por explante promedio (>3 se alcanzó al realizar varias heridas en forma de punteaduras en el nervio central de las hojas. Este protocolo de regeneración constituye una importante herramienta que puede ser empleada para futuros estudios de transformación genética en esta especie. Palabras clave: cultivo de tejidos, explantes de hoja, reguladores de crecimiento, organogénesis, guayaba.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

An improved protocol for efficient transformation and regeneration of diverse indica rice cultivars

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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

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

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H. Hadizadeh

2016-07-01

Full Text Available Introduction: Chicory (Cichorium intybus L. belongs to Asteraceae family is commonly known as witloof chicory. The leaves and the roots of this medicinal plant are edible and commonly used as salad. Some varieties are also cultivated as coffee substitute after roasting the roots. All parts of the plant contain these volatile oils, with the majority of the toxic components concentrated in the plant's root. In folk medicine, the plant is used for the treatment of diarrhea, spleen enlargement, fever, and vomiting. Antihepatotoxic activity on damaged rat’s liver sections and anti-bacterial activity of this crop has been recently reported. In vitro regeneration from leaf explants with various hormonal combinations has been reported previously. Moreover, in vitro regeneration of Chicory from cotyledon explants using different combinations of plant growth regulators has been studied. Also, a protocol for the regeneration of plantlets from leaf and petiole explants of witloof chicory has been developed. The aim of the present investigation was optimization of callus induction and shoot regeneration from leaf and petiole tissues of Chicory (Esfahan genotype. Materials and Methods: In this investigation, Esfahan genotype was used for callus induction and direct shoot regeneration. Seeds were first washed with running tap water for 30 min then seeds were surface sterilized by dipping in 70% ethanol for 90 s and rinsed with sterile distilled water, followed by immersing in 5% sodium hypochlorite solution for 25 min and thereafter rinsed for 30 min with sterile distilled water. The basal medium used in this investigation was MS. For shoot regeneration, leaf and petiole explants (5 mm segments were excised from 4-week-old sterile seedlings and cultured on MS medium containing different combinations of NAA / BA and KIN / BA in two separate experiments. Experiments were performed factorial based on completely randomized design. Cultures were incubated at 25�

High Frequency Multiple Shoot Induction of Curculigo orchioides Gaertn.: Shoot Tip V/S Rhizome Disc

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K. S. Nagesh

2008-09-01

Full Text Available Curculigo orchioides Gaertn. is an endangered medicinal plant with anticancer properties. The rhizome and tuberous roots of the plant have been used extensively in India in indigenous medicine. Due to its multiple uses, the demand for Curculigo orchioides is constantly on the rise; however, the supply is rather erratic and inadequate. Destructive harvesting, combined with habitat destruction in the form of deforestation has aggravated the problem. The plant is now considered ‘endangered’ in its natural habitat. Therefore, the need for conservation of this plant is crucial. Here, we describe a successful protocol for multiple shoot induction of C. orchioides using shoot tip and rhizome disc. We find that proximal rhizome discs are optimal for high frequency shoot bud formation than shoot tip and distal rhizome disc. We observed a synergistic effect between 6-benzylaminopurine (BAP and kinetin (KN (each at 1 mg/L on the regeneration of shoot buds from proximal rhizome disc than shoot tip explant. Optimum root induction was achieved on half-strength MS liquid medium supplemented with 1 mg/L of indole-3-butyric acid (IBA. The in vitro raised plantlets were acclimatized in green house and successfully transplanted to natural condition with 90% survival.

In vitro shoot multiplication and conservation of Caralluma ...

African Journals Online (AJOL)

Jane

2011-03-30

Burm. f.) Merrill. In Vitro Cell Deve. Biol. Plant. 41: 124-128. Thomas TD, Shankar S (2009). Multiple shoot induction and callus regeneration in Sarcostemma brevistigma Wight & Arnott, a rare medicinal plant. Plant Biotechnol.

Plant regeneration through organogenesis and shoot proliferation in ...

African Journals Online (AJOL)

STORAGESEVER

2008-10-20

Oct 20, 2008 ... Effect of 2,4-D, NAA and BA (in MS medium) on Trichodesma indicum callus induction and shoot .... Structure/activity relationships of the fenotoxic potentcies of sixteen pyrrolizidine ... In vitro propagation of Cordia verbe- ...

Shoot regeneration of limau purut (citrus hystrix) using shoot tip: assessment of calcium gluconate and silver nitrate in overcoming premature leaf senescence

International Nuclear Information System (INIS)

Eng, W.H.; Aziz, M.A.; Sinniah, U.R.

2014-01-01

This study was carried out to establish an optimum In vitro shoot multiplication system using shoot tip explants derived from 7 week-old seedlings of Citrus hystrix. In the first experiment, shoot tips were cultured on Murashige and Skoog (MS) medium supplemented with 0-13.33 mu M 6-benzylaminopurine (BAP) for 8 weeks. Shoot tips cultured on 2.22 mu M BAP produced the highest mean number of shoots (3.42 shoots) but the shoots had low number of leaves (1.14 leaves) due to the occurrence of premature leaf senescence and callus formation. Meanwhile, the medium devoid of BAP produced the lowest mean number of shoots (1.50 shoots) but highest mean number of leaves (5.41 leaves) indicating that BAP was likely responsible for the premature leaf senescence. In order to overcome the occurrence of premature leaf senescence on medium with BAP, a second experiment was carried out whereby shoot tips were cultured on medium containing 2.22 micro M BAP fortified with 2.00, 4.00 and 6.00 mM calcium gluconate (Ca-glu) and a control treatment with 2.22 mu M BAP. The shoot and leaf numbers were increased with the addition of 4.00 and 6.00 mM Ca-glu. The presence of Ca-glu reduced premature leaf senescence and callus formation to some extent. In the third experiment, the addition of silver nitrate (AgNO/sub 3/) at 10-80 micro M in media with 2.22 micro M BAP and 2.22 micro M BAP + 4 mM Ca-glu could totally overcome premature leaf senescence and callus formation. Media supplemented with 2.22 mirco M BAP + 4 mM Ca-glu + 20 micro M AgNOsub 3/ significantly induced among the highest mean number of shoots and highest mean number of leaves per shoot. (author)

An efficient protocol for regeneration and transformation of Symphyotrichum novi-belgii

DEFF Research Database (Denmark)

Mørk, Eline Kirk; Henriksen, Karin; Brinch-Pedersen, Henrik

2012-01-01

) fusion gene, and an enhanced green fluorescent protein gene. Pre-cultured hypocotyl explants were transformed in the presence of 100 μM acetosyringone using 90 s sonication plus 10 min vacuum-infiltration. Kanamycin at 20 mg l−1 was used for selecting transformed cells. Adventitious shoots regenerated......II genes in GUS-positive shoots were confirmed by PCR and copy number of the nptII gene in PCR-positive shoots was determined by Southern blotting. Three transgenic plantlets were acclimatized to the greenhouse. This transformation and regeneration system using hypocotyls provides a foundation...

Development of Sirococcus shoot blight following thinning in western hemlock regeneration.

Science.gov (United States)

Charles G. Shaw; Thomas H. Laurent; Spencer. Israelson

1981-01-01

Shoot mortality from Sirococcus strobilinus Preuss. and other causes was recorded by crown position from April 1978 through October 1979 in younggrowth western hemlock (Tsuga heterophylla (Raf.) Sarg.) crop trees released in a 1977 thinning at Thomas Bay, Alaska. All study trees contained some infected shoots, but no terminal...

Regeneration efficiency based on genotype, culture condition and growth regulators of eggplant (Solanum melongena L.

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Md Abdul Muktadir

2016-01-01

Full Text Available Several experiments were carried out to establish an efficient regenerating protocol for cultivated eggplant varieties. Among the five varieties cultured on Murashige and Skoog (MS medium with free plant growth regulator (PGR, Nayantara performed better considering the number of shoots/explant (2.48. Considering explant types and culture conditions, better performance was observed (3.68 shoots/explant when seed germination in the dark was proceeded by bottom hypocotyl segments cultured under dark conditions. A higher rate of shoot regeneration was observed in Nayantara when cultured in Zeatin Riboside (ZR and Thidizuron (TDZ supplemented MS medium. The highest number of shoots per explant was produced on MS medium supplemented with 2.0 mg/L ZR and 0.1 mg/L indole acetic acid (6.65 shoots/explant. Proliferation and elongation of the regenerated shoots were obtained in the MS medium with free PGR. The best rooting performance was observed in MS medium supplemented with 2.0 mg/L indole butyric acid. Plantlets with well developed roots and shoots were successfully transferred to soil.

Hyperinnervation improves Xenopus laevis limb regeneration.

Science.gov (United States)

Mitogawa, Kazumasa; Makanae, Aki; Satoh, Akira

2018-01-15

Xenopus laevis (an anuran amphibian) shows limb regeneration ability between that of urodele amphibians and that of amniotes. Xenopus frogs can initiate limb regeneration but fail to form patterned limbs. Regenerated limbs mainly consist of cone-shaped cartilage without any joints or branches. These pattern defects are thought to be caused by loss of proper expressions of patterning-related genes. This study shows that hyperinnervation surgery resulted in the induction of a branching regenerate. The hyperinnervated blastema allows the identification and functional analysis of the molecules controlling this patterning of limb regeneration. This paper focuses on the nerve affects to improve Xenopus limb patterning ability during regeneration. The nerve molecules, which regulate limb patterning, were also investigated. Blastemas grown in a hyperinnervated forelimb upregulate limb patterning-related genes (shh, lmx1b, and hoxa13). Nerves projecting their axons to limbs express some growth factors (bmp7, fgf2, fgf8, and shh). Inputs of these factors to a blastema upregulated some limb patterning-related genes and resulted in changes in the cartilage patterns in the regenerates. These results indicate that additional nerve factors enhance Xenopus limb patterning-related gene expressions and limb regeneration ability, and that bmp, fgf, and shh are candidate nerve substitute factors. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Direct adventitious shoot bud formation on hypocotyls explants in Millettia pinnata (L.) Panigrahi- a biodiesel producing medicinal tree species.

Science.gov (United States)

Nagar, Durga Singh; Jha, Suman Kumar; Jani, Jigar

2015-04-01

A reproducible protocol developed for in vitro regeneration of Milletia pinnata using hypocotyl segments. Multiple shoots were induced from hypocotyl explants through direct adventitious shoot bud regeneration. The proximal end of hypocotyls was responsive for shoot bud induction. Silver nitrate and adenine sulphate had a positive effect on shoot bud induction and elongation. The maximum response and number of shoot bud produced in media supplemented with 8.88 μM BAP with 108.6 μM adenine sulphate and 11.84 μM silver nitrate. Elongated shoots were harvested and successful rooting of microshoots achieved on MS media supplemented with 9.84 μM IBA, with 81.1 % rooting. Remaining shoot buds sub-cultured for further multiplication and elongation. Each subculture produced eight to nine elongated microshoots up to four subcultures. The rooted microshoots were successfully hardened and transferred to field.

Plant Regeneration Through Tissue Culture Of Pear Millet ...

African Journals Online (AJOL)

1. 1. 2,5), MS(5) and N6(1.100.25) culture media, calli embryogenic potential and fertile plants regeneration were conserved for more than 12 months. Characteristics of regenerated plants were similar to control. It appears that dissected shoot ...

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

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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.

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.

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)

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.

Efficient genetic transformation of Lotus corniculatus L. using a direct shoot regeneration protocol, stepwise hygromycin B selection, and a super-binary Agrobacterium tumefaciens vector

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Nikolić Radomirka

2007-01-01

Full Text Available Cotyledons from 6-day-old Lotus corniculatus cv. Bokor seedlings, transversally cut into two halves, were capa­ble of regenerating buds without intervening callus formation. The explants were co-cultivated with the Agrobacterium tumefaciens LBA4404/pTOK233 superbinary vector carrying the uidA-intron gene and the genes hpt and nptII. They were cultured for 14 days on a regeneration medium, then subjected to a stepwise hygromycin B selection procedure consisting of gradually increasing antibiotic concentrations (5-15 mg L-1 over 21 weeks. Transformed shoots were obtained within 5 months after co-cultivation. Out of 124 initially co-cultivated explants, 52 (42% plants survived hygromycin B selection. The presence of transgenes in regenerated plants was verified by β-glucuronidase histochemical assays and PCR analysis for the presence of uidA gene sequences. Hygromycin B-resistant and PCR-positive T0 plants were cultured in the greenhouse to produce flowers and seeds. The obtained data demonstrate that the reported transformation protocol could be useful for introducing agriculturally important genes into the new L. corniculatus cultivar Bokor.

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.

PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

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I Gusti Ngurah Agung Cahya Prananta

2015-01-01

Full Text Available The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on 20samples of people whowere selected randomly from the men's basketball club of the Faculty of Physical Educationand Health of Teacher Training Institute PGRI Bali. Samples were divided into two groups each  consisting of 10 people. Group I was given training step  jump shoot four sets of 10 reps  and Group II training still jump shoot four sets of 10 reps. The data before and after treatment were tested by SPSS computer program. The data were normally distributed and homogeneous so further tested using pairedt-test to compare the average values?? before and after training between each group, while the independent t-test was used to determine differences in mean values?? between the two groups. Paired t-test resulted the obtained data were significantly increased in both treatment groups p=0,001 in Group I and p=0,000 in Group II (p <0.05. Results of independent t-test found that both groups before training did not differ significantly p=0,926 (p>0.05 and after training both groups equally improve the accuracy of shooting because p=0,133 (p>0.05. It was concluded that botht raining improved the shooting accuracy and there was no difference between the effect of step jumps hoot and still jump shoot toward the shooting accuracy. It was suggested to improve the shooting accuracy in basketball used step jump shoot training and still jump shoot training four sets of 10 reps with a training frequency of 4 times a week for 6 weeks

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)

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

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

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)

Genetic stability among date palm plantlets regenerated from petiole ...

African Journals Online (AJOL)

The regeneration capacity between the shoot tip and petiole explants that excised from two date palm (Phoenix dactylifera L.) cutivar namely Unknown and Ferhi was compared. It was noted that the shoot tip explants started to swill after several subculture when placed on Murashige and Skoog (MS) medium supplemented ...

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.

A fasciclin-like arabinogalactan-protein (FLA mutant of Arabidopsis thaliana, fla1, shows defects in shoot regeneration.

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Kim L Johnson

Full Text Available BACKGROUND: The fasciclin-like arabinogalactan-proteins (FLAs are an enigmatic class of 21 members within the larger family of arabinogalactan-proteins (AGPs in Arabidopsis thaliana. Located at the cell surface, in the cell wall/plasma membrane, they are implicated in many developmental roles yet their function remains largely undefined. Fasciclin (FAS domains are putative cell-adhesion domains found in extracellular matrix proteins of organisms from all kingdoms, but the juxtaposition of FAS domains with highly glycosylated AGP domains is unique to plants. Recent studies have started to elucidate the role of FLAs in Arabidopsis development. FLAs containing a single FAS domain are important for the integrity and elasticity of the plant cell wall matrix (FLA11 and FLA12 and FLA3 is involved in microspore development. FLA4/SOS5 with two FAS domains and two AGP domains has a role in maintaining proper cell expansion under salt stressed conditions. The role of other FLAs remains to be uncovered. METHOD/PRINCIPAL FINDINGS: Here we describe the characterisation of a T-DNA insertion mutant in the FLA1 gene (At5g55730. Under standard growth conditions fla1-1 mutants have no obvious phenotype. Based on gene expression studies, a putative role for FLA1 in callus induction was investigated and revealed that fla1-1 has a reduced ability to regenerate shoots in an in vitro shoot-induction assay. Analysis of FLA1p:GUS reporter lines show that FLA1 is expressed in several tissues including stomata, trichomes, the vasculature of leaves, the primary root tip and in lateral roots near the junction of the primary root. CONCLUSION: The results of the developmental expression of FLA1 and characterisation of the fla1 mutant support a role for FLA1 in the early events of lateral root development and shoot development in tissue culture, prior to cell-type specification.

PERBANDINGAN JUMP SHOOT DENGAN AWALAN DAN TANPA AWALAN TERHADAP PENINGKATAN KETEPATAN SHOOTING DALAM PERMAINAN BOLABASKET

OpenAIRE

I Gusti Ngurah Agung Cahya Prananta; N. Adiputra; I P G Adiatmika

2015-01-01

The effectiveness of  jump-shoot technique step jump shoot and still jump shoot in a game is still questionable,  because many different assumptions arise. One opinion stated that step jump shoot was more effective and the other stated that and still jump shoot was more efective. Therefore it is necessary to do research on the analysis of the results of step jump shoot and and still jump shoot to improve the accuracy of shooting in a basketball. The experimental research had been conducted on...

Organ and plantlet regeneration of Menyanthes trifoliata through tissue culture

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Urszula Adamczyk-Rogozińska

2014-01-01

Full Text Available The conditions for the regeneration of plants through organogenesis from callus tissues of Menyanthes trifoliata are described. The shoot multiplication rate was affected by basal culture media, the type and concentration of cytokinin and subculture number. The best response was obtained when caulogenic calli were cultured on the modified Schenk and Hildebrandt medium (SH-M containing indole-3-acetic acid (IAA 0,5 mg/l and 6-benzyladenine (BA 1 mg/l or zeatin (2 mg/l. Under these conditions ca 7 shoots (mostly 1 cm or more in length per culture in the 5th and 6th passages could be developed. In older cultures (after 11-12 passages there was a trend for more numerous but shorter shoot formation. All regenerated shoots could be rooted on the SH-M medium supplemented with 0.5 mg/l IAA within 6 weeks; 80% of in vitro rooted plantlets survived their transfer to soil.

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 ...

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...

Improvement characteristics shown in holistic regeneration of Ballymun toward sustainable community

Energy Technology Data Exchange (ETDEWEB)

Lee, Yeunsook; Lim, Soohyun; Kim, Gunhyoung [Department of Housing and Interior Design, Yonsei University, Seoul (Korea)

2010-02-15

Substantial numbers of urban and residential environments constructed in the 20th century are experiencing degeneration and the importance of challenging to revitalize community holistically is getting more seriously recognized. There, however, has been limitation in grasping the holistic regeneration information as urban regeneration usually goes through a long-term and complicated procedure. Yet, the urban and housing regeneration's direction is required to be holistic in the 21st Century. Any precedent case that had tried the holistic regeneration needs to be checked thoroughly and thereby the result needs to be applied to the future attempts as a reference and knowledge base. The purpose of this study was to delineate improvement characteristics that appeared during the course of holistic regeneration in Ballymun of Ireland. This research is an archival research in nature which also used content analysis technique since it deals with reports and newsletters as archival records that were accumulated on a regular base throughout the whole process. The leading projects continued over ten years of improvement were scrutinized in the perspective of physical, social, economic, cultural, and environmental dimensions of regeneration. The main results were, first, a series of improvement activities and projects to regenerate each of five dimensions were delineated for comprehensive understanding. Second, connected patterns for synergistic improvement were identified and patterns were described to show the detailed contents as examples. This study would provide communities that face holistic regeneration, an insight, planning skills, creative and realistic ideas for implementation, thereby empowers planning capability toward holistic regeneration. (author)

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

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

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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

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 ...

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 ...

Cryopreservation of in vitro grown shoot tips and apical meristems of the forage legume Arachis pintoi.

Science.gov (United States)

Rey, Hebe Y; Faloci, Mirta; Medina, Ricardo; Dolce, Natalia; Mroginski, Luis; Engelmann, Florent

2009-01-01

A cryopreservation protocol using the encapsulation-dehydration procedure was established for shoot tips (2-3 mm in length) and meristems (0.3-0.5 mm) sampled from in vitro plantlets of diploid and triploid cytotypes of Arachis pintoi. The optimal protocol was the following: after dissection, explants were precultured for 24 h on establishment medium (EM), encapsulated in calcium alginate beads and pretreated in liquid EM medium with daily increasing sucrose concentration (0.5, 0.75, 1.0 M) and desiccated to 22-23 percent moisture content (fresh weight basis). Explants were frozen using slow cooling (1 C per min from 25C to -30C followed by direct immersion in liquid nitrogen), thawed rapidly and post-cultured in liquid EM medium enriched with daily decreasing sucrose concentrations (0.75, 0.50, 0.1 M). Explants were then transferred to solid EM medium in order to achieve shoot regeneration, then on Murashige and Skoog medium supplemented with 0.05 microM naphthalene acetic acid to induce rooting of shoots. With this procedure, 53 percent and 56 percent of cryopreserved shoot tips of the diploid and triploid cytotypes, respectively, survived and formed plants. However, only 16 percent of cryopreserved meristems of both cytotypes regenerated plants. Using ten isozyme systems and seven RAPD profiles, no modification induced by cryopreservation could be detected in plantlets regenerated from cryopreserved material.

Regeneration of Pelargonium in vitro

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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.

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

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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.

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

Full Text Available Introduction: Fenugreek (Trigonella foenum- graecum is a medicinal plant extensively distributed in most regions of the world. Fenugreek is an annual plant from the family of papilionaceae, leguminosae. Fenugreek leaves and seeds have been used extensively to prepare extracts and powders for medicinal uses. Its root, leaf and seed contain a number of important medicinal compounds such as polysaccharide, galactomannan, different saponins such as diosgenin, yamogenin, mucilage, volatile oil and alkaloids such as choline and trigonelline. Plant tissue culture is fundamental to most aspects of biotechnology of plants. Establishment of an efficient callus induction and direct regeneration protocol is an essential prerequisite in harnessing the advantage of cell and tissue culture for genetic improvement. For the successful application of the tissue culture technique in plant breeding, callus induction and plant regeneration potential of each plant must be determined. The present study was performed in order to determine the optimum concentration of plant growth regulators (IBA + TDZ for producing of in vitro plantlet using cotyledon and hypocotyl as an explant for two different Iranian genotypes (Ardestani and Neyshabouri. Materials and Methods: In this investigation, Ardestani and Neyshabouri genotypes were used for callus induction and direct shoot regeneration. The medium used in this investigation was MS (Murashige and Skoog basal medium. Then seeds were germinated on MS medium. For callus induction and direct shoot regeneration, cotyledon and hypocotyl explants were excised from 8-day-old sterile seedlings and cultured on MS medium containing various concentrations of IBA and TDZ. In this experiment, two combinations (TDZ + IBA were used. In the first composition, IBA had four levels (0, 0.1, 0.3, 0.5 mg l-1 and TDZ had five levels (0, 0.2, 0.4, 0.6, 0.8 mg l-1 and in the second composition, IBA had four levels (0, 0.05, 0.1, 0.15 mg l-1 and TDZ

Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants

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JAIME A. TEIXEIRA DA SILVA

2015-05-01

Full Text Available Abstract. Teixeira da Silva JA. 2015. Response of Syngonium podophyllum L. ‘White Butterfly’ shoot cultures to alternative media additives and gelling agents, and flow cytometric analysis of regenerants. Nusantara Bioscience 7: 26-32. Syngonium podophyllum L. (arrowhead vine is a popular leafy indoor pot plant whose tissue culture has been established, primarily through in vitro shoot culture, but several interesting aspects have not yet been explored. In this study, cv. ‘White Butterfly’ was used to investigate the response of shoot formation to alternative gelling agents and media additives. Gellan gum (Gelrite® at 2 g/L resulted in greater leaf production, plantlet fresh weight and higher chlorophyll content (SPAD value than all other gelling agents tested, including agar, Bacto agar, phytagel, oatmeal agar, potato dextrose agar, barley starch and corn starch, when on a basal Hyponex® (NPK = 6.5: 6: 19; 3 g/L medium. Several alternative liquid medium additives tested (low and full fat milk, Coca-Cola®, coffee, Japanese green, Oolong and Darjeeling teas negatively impacted plant growth, stunted roots and decreased chlorophyll content (SPAD value of leaves. Plant growth on medium with refined sucrose or table sugar responded similarly. Poor growth was observed when crude extract from a high rebaudioside-containing stevia (Stevia rebaudiana Bertoni line - an artificial sweetener - was used. Leaf tissue from the control did not show any endopolyploidy but low levels of endopolyploidy (8C were detected in some treatments.

Assessment of the potentiality of TDZ on multiple shoot induction in Bauhinia tomentosa L., a woody legume.

Science.gov (United States)

Naz, Ruphi; Anis, M; Aref, I M

2012-12-01

An efficient and reproducible protocol for in vitro multiplication of Bauhinia tomentosa L. was developed. Multiple shoots were regenerated from cotyledonary node and stem nodal segments excised from in vitro raised seedlings on Murashige and Skoog (MS) medium supplemented with different concentrations (0.1, 0.3, 0.5, 0.8 and 1.0 μM) of thidiazuron (TDZ). The maximum response (62.6%) was recorded on MS medium amended with 0.8 μM TDZ. A long exposure to TDZ for 8 weeks showed abnormalities such as fasciation and compact shoots formation. To avoid adverse effects of prolonged exposure to TDZ in long-term establishment, the culture were transferred to TDZ free MS medium for further multiplication and elongation. The highest number of shoots and shoot length were recorded at the end of fourth subculture passage. Ex vitro rooting was achieved when the basal cut end of regenerated shoots were dipped in 200 μM indole-3-butyric acid (IBA) for half an hour followed by their transplantation in plastic pots filled with sterile Soilrite™ where 60% plantlets grew well and all expressed normal development.

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

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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.

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

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Dikash Singh THINGBAIJAM

2014-03-01

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

Influence of calcium content of tissue on hyperhydricity and shoot-tip necrosis of in vitro regenerated shoots of Lavandula angustifolia Mill.

Directory of Open Access Journals (Sweden)

Marília Pereira Machado

2014-10-01

Full Text Available In the present study, the effects of two CaCl2.2H2O levels (440 and 1320 mg L-1 and two subcultures were evaluated on in vitro shoots of Lavandula angustifolia cv. Provence Blue. Ca2+ content of the apical, middle and basal portion of shoots was determined. Increasing CaCl2.2H2O level in the culture medium increased tissue Ca2+ content and decreased hyperhydricity. Shoot-tip necrosis also decreased with 1320 mg L-1 CaCl2.2H2O, but it did not occur in the second subculture. The middle and basal portion had higher Ca2+ content than apical portion. In non-hyperhydric tissues, there were smaller and more juxtaposed cells. Scanning electron microscopy of the leaves demonstrated that trichomes from in vitro leaf surface occurred in smaller quantities.

In vitro propagation of Cymbidium goeringii Reichenbach fil. through direct adventitious shoot regeneration.

Science.gov (United States)

Park, Han Yong; Kang, Kyung Won; Kim, Doo Hwan; Sivanesan, Iyyakkannu

2018-03-01

The influence of 2,4-dichlorophenoxyacetic acid (2,4-D), benzyladenine (BA), and thidiazuron (TDZ) on direct rhizome induction and shoot formation from rhizome explants of Cymbidium goeringii was explored. Rhizome segments obtained from in vitro seed cultures of C. goeringii were placed on Murashige and Skoog (MS) medium incorporated with 5, 10, 20, or 40 µM 2,4-D and 1, 2, 4, or 8 µM BA or TDZ alone or in combination with 20 µM 2,4-D. The explants developed only rhizomes on MS medium with or without 2,4-D. The highest percent of rhizome formation (100%) was obtained on MS medium incorporated with 20 μM of 2,4-D. The morphology and number of rhizomes varied with the level of 2,4-D in the medium. Direct adventitious shoot formation was achieved on medium incorporated with BA or TDZ. The adventitious shoots produced per explant significantly increased with the supplementation of 2,4-D to cytokinin-containing medium. The highest mean of 21.8 ± 1.8 shoot buds per rhizome segment was obtained in medium fortified with 20 μM 2,4-D and 2 μM TDZ. The greatest percent of root induction (100%) and the mean of 5.3 ± 1.1 roots per shoot were achieved on ½ MS medium incorporated with 2 μM of α-naphthaleneacetic acid. About 97% of the in vitro-produced plantlets acclimatized in the greenhouse. An efficient in vitro propagation protocol was thus developed for C. goeringii using rhizome explants.

Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution.

Science.gov (United States)

Kumar, Sunil; Rai, Manoj K; Singh, Narender; Mangal, Manisha

2010-12-01

Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.

In vitro shoot regeneration of fenugreek (Trigonella foenum-graecum ...

African Journals Online (AJOL)

Jane

2010-10-18

Oct 18, 2010 ... sprouts are good source of protein, mineral and vitamin C. (Khan et al. ... hypocotyl explants were isolated from 8 - 10 days old germinated seedlings and ..... TJV (1993). Transformation and regeneration of two cultivars of pea.

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.

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.

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

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K. V. Derkach

2013-11-01

Full Text Available In connection with the necessity of bringing elite maize inbreds of the Lancaster germplasm group, which have potential for cultivation in Ukraine, into the system of genetic tranformation, the aim of this investigation is to identify the ability of maize inbreds of this group to regenerate by direct organogenesis and to determine the optimal mineral basis for their nutritional environment using segments of the node area of shoots. As explantats we used sterile 4-day old seedlings of 4 maize inbreds of Lancaster germplasm and model inbred Chi31 exotic germplasm. The seedlings were obtained by germination of sterile seeds in Petri dishes between two layers of moist sterile filter paper at a temperature of 27 ºC in dark conditions. A single 1 cmlong segment was cut from each from each seedling, running from 0.5 cmbefore the node to 0.5 cmafter the node. A cut was made in each segment of the node in order to create a wounded surface. Explantats were planted in a nutrient environment with mineral bases of MS or N6, modified by the addition of 10 mg/l silver nitrate, 100 mg/l casein hydrolyzate, 690 mg/l L-proline, 30 g/l sucrose, 1.0 mg/l 2,4-dychlorphenoksiacetic acid and 0,1 mg/l abscisic acid. Cultivation was carried out at 25–27 ºC in the light. Direct hemogenesis in this environment on the 14th day of cultivation in vitro reached 100% for each line. This meant that all researched lines of Lancaster germplasm and the model line showed a high capacity for direct regeneration through direct hemogenesis, which does not depend on the composition of the mineral content of their nutritional environment. Callus formation was observed in all genotypes on the 14th day of cultivation in vitro and the extent of its formation increased during the following month of cultivation. The callus formation was observed only at the site of the wounded surface. The calluses were transparent. Although green areas appeared in these calluses, they were

PEMBELAJARAN LAY UP SHOOT MENGGUNAKAN MEDIA AUDIO VISUAL BASIC LAY UP SHOOT UNTUK MENINGKATKAN HASILBELAJAR LAY UP SHOOT PADA SISWA KELAS VIIIA SMP KANISIUS PATI TAHUN 2013/2014

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Frendy Nurochwan Febryanto

2015-01-01

Full Text Available The purpose of this study was to determine the learning lay up shoot using basic audiovisual media shoot lay ups can improve learning outcomes shoot lay ups in class VIIIA Starch Canisius junior year 2013/2014 . This study uses Classroom Action Research ( CAR. The technique of collecting data through observation and assessment of learning outcomes shoot basketball lay up. Data analysis techniques used in this research is descriptive . At the end of the first cycle activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 76.19%, whereas at the end of the first cycle of student activity during the learning process lay up shoot using audio-visualmediareaches78.57%. At the end of the second cycle of activity of teachers in teaching basic techniques lay up shoot using audio-visual media reaches 85.71%, whereas at the end of the second cycle of activity of students during the learning process lay up shoot using audio-visual media reaches 92.86%. Based on the results of the study it can be concluded that learning the lay-up shoot using basic audiovisual media shoot lay ups can improve student learning outcomes at Canisius junior class VIIIA Pati year 2013/2014.

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

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Dikash Singh THINGBAIJAM

2014-03-01

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

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

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)

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)

Improving Mental Health Through the Regeneration of Deprived Neighborhoods: A Natural Experiment.

Science.gov (United States)

White, James; Greene, Giles; Farewell, Daniel; Dunstan, Frank; Rodgers, Sarah; Lyons, Ronan A; Humphreys, Ioan; John, Ann; Webster, Chris; Phillips, Ceri J; Fone, David

2017-08-15

Neighborhood-level interventions provide an opportunity to better understand the impact of neighborhoods on health. In 2001, the Welsh Government, United Kingdom, funded Communities First, a program of neighborhood regeneration delivered to the 100 most deprived of the 881 electoral wards in Wales. In this study, we examined the association between neighborhood regeneration and mental health. Information on regeneration activities in 35 intervention areas (n = 4,197 subjects) and 75 control areas (n = 6,695 subjects) was linked to data on mental health from a cohort study with assessments made in 2001 (before regeneration) and 2008 (after regeneration). Propensity score matching was used to estimate the change in mental health in intervention neighborhoods versus control neighborhoods. Baseline differences between intervention and control areas were of similar magnitude as produced by paired randomization of neighborhoods. Regeneration was associated with an improvement in the mental health of residents in intervention areas compared with control neighborhoods (β = 1.54, 95% confidence interval: 0.50, 2.59), suggesting a reduction in socioeconomic inequalities in mental health. There was a dose-response relationship between length of residence in regeneration neighborhoods and improvements in mental health (P-trend = 0.05). These results show that targeted regeneration of deprived neighborhoods can improve mental health. © The Author(s) 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health.

Callus induction and plant regeneration of Ulex europaeus

OpenAIRE

Ramírez,Ingrid; Dorta,Fernando; Cuadros-Inostroza,Álvaro; Peña-Cortés,Hugo

2012-01-01

A callus induction and plant regeneration protocol was developed from leaf and thorn explants for the plant Ulex europaeus. Explants were incubated on 2% sucrose half-strength Murashige and Skoog Medium (MS) with various combinations of plant growth regulators and antioxidants. The best frequency of callus and shoot formation was obtained with 2,4-dichlorophenoxyacetic acid (2,4-D) 1 mg/l x kinetin (Kin) 0.2 mg/l (DK Medium; callus induction) and zeatin (Z) 1 mg/l (DK medium; shoot induction)...

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.

The influence of different hormone concentration and combination on callus induction and regeneration of Rauwolfia serpentina L. Benth.

Science.gov (United States)

Salma, U; Rahman, M S M; Islam, S; Haque, N; Jubair, T A; Haque, A K M F; Mukti, I J

2008-06-15

The influence of media composition on callus induction and subsequent regeneration of Rauwolfia serpentina L. Benth has been studied. High frequency (96.43%) callus induction was obtained when nodal segments from in vitro raised shoots were cultured on MS medium supplemented with 0.5 mg L(-1) BA and 2.0 mg L(-1) NAA. The callus differentiated into adventitious shoots when it was subcultured on MS medium supplemented with 2.0 mg L(-1) BA with 0.2 mg L(-1) NAA. Regenerated shoots were best rooted on half-strength MS medium with 1.0 mg L(-1) each of IBA and IAA.

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

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Gaurav Aggarwal

2012-11-01

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

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

Acetylcholine suppresses shoot formation and callusing in leaf explants of in vitro raised seedlings of tomato, Lycopersicon esculentum Miller var. Pusa Ruby.

Science.gov (United States)

Bamel, Kiran; Gupta, Rajendra; Gupta, Shirish C

2016-06-02

We present experimental evidence to show that acetylcholine (ACh) causes decrease in shoot formation in leaf explants of tomato (Lycopersicon esculentum Miller var Pusa Ruby) when cultured on shoot regeneration medium. The optimum response was obtained at 10(-4) M ACh-enriched medium. ACh also causes decrease in percentage of cultures forming callus and reduces the callus mass. Inhibitors of enzymatic hydrolysis of ACh, neostigmine and physostigmine, also suppresses callogenesis and caulogenesis. On the other hand, the breakdown products of Ach, choline and acetate, do not alter the morphogenic response induced on the shoot regeneration medium. Neostigmine showed optimal reduction in shoot formation at 10(-5) M. The explants cultured on neostigmine augmented medium showed decline in the activity of ACh hydrolyzing enzyme acetylcholinesterase. ACh and neostigmine added together showed marked reduction in callus mass. These results strongly support the role of ACh as a natural regulator of morphogenesis in tomato plants.

Acetylcholine suppresses shoot formation and callusing in leaf explants of in vitro raised seedlings of tomato, Lycopersicon esculentum Miller var. Pusa Ruby

Science.gov (United States)

Bamel, Kiran; Gupta, Rajendra; Gupta, Shirish C.

2016-01-01

ABSTRACT We present experimental evidence to show that acetylcholine (ACh) causes decrease in shoot formation in leaf explants of tomato (Lycopersicon esculentum Miller var Pusa Ruby) when cultured on shoot regeneration medium. The optimum response was obtained at 10−4 M ACh-enriched medium. ACh also causes decrease in percentage of cultures forming callus and reduces the callus mass. Inhibitors of enzymatic hydrolysis of ACh, neostigmine and physostigmine, also suppresses callogenesis and caulogenesis. On the other hand, the breakdown products of Ach, choline and acetate, do not alter the morphogenic response induced on the shoot regeneration medium. Neostigmine showed optimal reduction in shoot formation at 10−5 M. The explants cultured on neostigmine augmented medium showed decline in the activity of ACh hydrolyzing enzyme acetylcholinesterase. ACh and neostigmine added together showed marked reduction in callus mass. These results strongly support the role of ACh as a natural regulator of morphogenesis in tomato plants. PMID:27348536

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

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

Full Text Available Introduction: Plant tissue culture is a collection of techniques used to maintain or grow plant cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition and widely used to produce clones of a plant in a method known as micropropagation. Plant research often involves growing new plants in a controlled environment. These may be plants that we have genetically altered in some way or may be plants of which we need many copies all exactly alike. These things can be accomplished through tissue culture of small tissue pieces from the plant of interest. These small pieces may come from a single mother plant or they may be the result of genetic transformation of single plant cells which are then encouraged to grow and to ultimately develop into a whole plant. Tissue culture techniques are often used for commercial production of plants as well as for plant research. Tobacco (Nicotiana tabacum L. is one of the most important model plants used in the physiologic, genetic and tissue culture studies. The manipulation of tobacco genetic structure requires an efficient technique of gene transferring and regeneration. Whereas, the tobacco plant is a very effective bioreactor in the production of recombinant proteins, in this research we optimized the best tissue culture system and also, genetic transformation process of this plant. Materials and Methods: Our plant tissue culture protocols, Include helpful information for Murashige and Skoog media, plant growth regulators, plant growth hormones, plant transformation systems, and other products for plant tissue culture. For this purpose, different concentrations of sucrose and 4 combinations of growth regulators (BAP and NAA on callus induction, direct shoot regeneration and rooting were examined in a factorial experiment based on completely randomized design with 3 replications. The sensitivity of tobacco explants to kanamycin was examined through the cultivation of them

Improvement of two-stage GM refrigerator performance using a hybrid regenerator

International Nuclear Information System (INIS)

Ke, G.; Makuuchi, H.; Hashimoto, T.; Onishi, A.; Li, R.; Satoh, T.; Kanazawa, Y.

1994-01-01

To improve the performance of two-stage GM refrigerators, a hybrid regenerator with magnetic materials of Er 3 Ni and ErNi 0.9 Co 0.1 was used in the 2nd stage regenerator because of its large heat exchange capacity. The largest refrigeration capacity achieved with the hybrid regenerator was 0.95W at helium liquefied temperature of 4.2K. This capacity is 15.9% greater than the 0.82W refrigerator with only Er 3 Ni as the 2nd regenerator material. Use of the hybrid regenerator not only increases the refrigeration capacity at 4.2K, but also allows the 4K GM refrigerator to be used with large 1st stage refrigeration capacity, thus making it more practical

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 ...

Physical exercises to improve the stability of the target sight in sport shooting

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Mercedes Miló Dubé

2017-04-01

Full Text Available Sport shooting stands for a highly technical sport, and a competitive art. It is the target sight one of the more important technical elements because it favors the sport performance and it must be considered in the training sessions from the junior school categories. This research meets the goals of proposing a set of physical exercises to improve the stability of the target sight technique for the Shooting athletes, category 13-16, field Standard gun pistol in the Sport School “Ormani Arenado Llonch” in Pinar del Río, Cuba. To fulfill this objective it was applied scientific observation, surveys and interviews, theoretical methods were also used in this research adjusted to 11 athletes and 3 coaches as the sample of research belonging to this school under study. Based on the diagnosed weaknesses found along the training was selected a set of physical exercise to improve the target sight empowering the pedagogical implication and without breaking the planning process of the sport.

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.

In vitro regeneration of Turkish dwarf chickling (Lathyrus cicera L ...

African Journals Online (AJOL)

STORAGESEVER

2008-06-17

Jun 17, 2008 ... Key words: Immature zygotic embryos, dwarf chickling, Lathyrus cicera L., axillary shoot regeneration, ... are widely used as animal feed in green and dry form or ..... Hanbury CD, White CL, Mullan BP, Siddique KHM (2000).

Micropropagation of chokeberry by in vitro axillary shoot proliferation.

Science.gov (United States)

Litwińczuk, Wojciech

2013-01-01

The black chokeberry-aronia (Aronia melanocarpa Elliot) is a shrub native to North America although nowadays well known in Eastern Europe. The fruits are regarded as the richest source of antioxidant phytonutrients among fruit crops and vegetables. Chokeberries can be easily propagated by seeds but this method is not recommended. Micropropagation is far more efficient than other conventional cloning methods like layering or softwood cuttings. Aronia clones are propagated in vitro through four- or three-stage method based on subculturing of shoot explants. The double diluted MS or full strength MS medium with elevated 50% Ca(2+) and Mg(2+) content are used in the initiation and proliferation chokeberry in vitro cultures, respectively. They are supplemented with 0.5-1.0 mg LBA, and 0.05 mg LIBA. The double-phase medium is recommended in the last passage before shoot rooting. The regenerated shoots could be rooted both in vitro on double diluted MS with 0.05 mg L(-1) IBA or in vivo in peat and perlite substrate and subsequently grown in the greenhouse.

Use of protoplast, cell, and shoot tip culture in an elm germ plasm improvement program

Science.gov (United States)

R. Daniel Lineberger; M.B. Sticklen; P.M. Pijut; Mark A. Kroggel; C.V.M. Fink; S.C. Domir

1990-01-01

An elm germplasm improvement program was established using three distinct approaches: (1) development of protoplast regeneration protocols with the goal of attempting somatic hybridization between Ulmus americana and disease resistant hybrids; (2) evaluation of the extent of somaclonal variation in plants regenerated from protoplasts; and (3)...

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.

In-vitro regeneration of castor bean (ricinus communis, L) and physic nut (jatropha curcas, L.)

International Nuclear Information System (INIS)

Afful, N. T.

2008-06-01

Investigations were conducted on in vitro regeneration of physic nut (Jatropha curcas, 1.) and castor bean (Ricinus communis, 1.) using zygotic embryo culture, shoot tip and meristem culture as well as somatic embryogenesis. Zygotic embryos from different stages of fruit maturity cultured on Murashige and Skoog (MS) medium supplemented with benzylaminopurine (BAP), kinetin and 2-isopentyl (2iP) produced vigorous seedlings with roots. However the optimal concentration of cytokinin for seedling development depended on the type cytokinin as well as the maturity stage of the fruit. Embryos from yellow fruits of Jatropha had the highest germination (100%) on an MS medium supplemented with 0.5 mg/L kinetin or 1 mg/L BAP while in Ricinus embryos from black fruits had the highest percentage germination (97%) on an MS medium modified with I mg/L 2iP or 0.5 or I mg/L BAP. Decrease in embryo viability especially in Jatropha as the seed matured may be due to high oil content in matured (black) fruit. Oil content in both Jatropha and Ricinus increased as the fruit matured from green to black and this may have effect on germination of zygotic embryos. In vitro culture response of shoot tip or meristem was significantly influenced by the concentration of growth regulators in the culture medium as well as the plant species. In both plant species, 2iP resulted in highest percentage shoot regeneration. The optimal concentration of 2iP was 0.5 mg/L for Ricinus shoot tip and 1.5 or 2.0 mg/L for Jatropha, indicating genotypic difference between the species. However excessive callus formation and browning in Ricinus led to the loss of all the regenerants. Shoot regeneration from meristem explants was also influenced by growth regulators with 2iP again being the best. Cultures of cotyledon and leaf lobe explants on MS medium supplemented with 2, 4-D and picloram resulted in callus induction with the exception of cotyledons obtained from black fruits. However transfer of calli onto fresh

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 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.

Interactions of phytochromes A, B1 and B2 in light-induced competence for adventitious shoot formation in hypocotyl of tomato (Solanum lycopersicum L.).

Science.gov (United States)

Lercari, B; Bertram, L

2004-02-01

The interactions of phytochrome A (phyA), phytochrome B1 (phyB1) and phytochrome B2 (phyB2) in light-dependent shoot regeneration from the hypocotyl of tomato was analysed using all eight possible homozygous allelic combinations of the null mutants. The donor plants were pre-grown either in the dark or under red or far-red light for 8 days after sowing; thereafter hypocotyl segments (apical, middle and basal portions) were transferred onto hormone-free medium for culture under different light qualities. Etiolated apical segments cultured in vitro under white light showed a very high frequency of regeneration for all of the genotypes tested besides phyB1phyB2, phyAphyB1 and phyAphyB1phyB2 mutants. Evidence is provided of a specific interference of phyB2 with phyA-mediated HIR to far-red and blue light in etiolated explants. Pre-treatment of donor plants by growth under red light enhanced the competence of phyB1phyB2, phyAphyB1 and phyAphyB1phyB2 mutants for shoot regeneration, whereas pre-irradiation with far-red light enhanced the frequency of regeneration only in the phyAphyB1 mutant. Multiple phytochromes are involved in red light- and far-red light-dependent acquisition of competence for shoot regeneration. The position of the segments along the hypocotyl influenced the role of the various phytochromes and the interactions between them. The culture of competent hypocotyl segments under red, far-red or blue light reduced the frequency of explants forming shoots compared to those cultured under white light, with different genotypes having different response patterns.

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.

Tissue culture regeneration and radiation induced mutagenesis in banana

International Nuclear Information System (INIS)

Kulkarni, V.M.; Ganapathi, T.R.

2009-01-01

Radiation induced mutagenesis is an important tool for banana genetic improvement. At BARC, protocols for shoo-tip multiplication of commercial banana varieties have been developed and transferred to user agencies for commercial production. Excellent embryogenic cell suspensions were established in banana cvs. Rasthali and Rajeli, and were maintained at low temperatures for long-term storage. Normal plantlets were successfully regenerated from these cell suspensions. The cell suspensions and shoot-tip cultures were gamma-irradiated for mutagenesis. The mutagenized populations were field screened and a few interesting mutants have been isolated. The existence of genetic variation was confirmed using DNA markers. Further evaluation of these mutants is in progress. (author)

Monochromic radiation through light-emitting diode (LED positively augments in vitro shoot regeneration in Orchid (Dendrobium sonia

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Vandita Billore

2017-07-01

Full Text Available Monochromatic lights emitted by light-emitting diodes (LEDs have generated great interest for efficient and controlled growth in vitro, especially of plants which are endangered or require specific intensity and wavelength of light. In the present study, we have evaluated the effect of monochromatic LEDs on in vitro morphogenesis: growth, proliferation of shoot cultures, and rooting of Dendrobium sonia. Different light sources viz. white LEDs (W, blue LEDs (B, yellow LEDs (Y and red LEDs (R were tested under photoperiod of 16 h of exposure and 8 h of dark. The frequency of morphogenesis depended on the wavelength of the applied monochromatic light. Higher wavelength monochromatic light (yellow light was observed to induce higher shoot proliferation (98%, early PLB (protocorm-like bodies formation, differentiation into green buds and shoot initiation as compared to red, blue and white light treatments. Yellow light also yielded higher number of shoots per explants (29 shoots/explant than red, blue and white light treatments. The results suggest that the monochromatic light sources stimulate morphogenic effects on in vitro culture of Dendrobium sonia, and that yellow light treatment can be used to enhance the efficiency of micropropagation.

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)

[Experimental studies for the improvement of facial nerve regeneration].

Science.gov (United States)

Guntinas-Lichius, O; Angelov, D N

2008-02-01

Using a combination of the following, it is possible to investigate procedures to improve the morphological and functional regeneration of the facial nerve in animal models: 1) retrograde fluorescence tracing to analyse collateral axonal sprouting and the selectivity of reinnervation of the mimic musculature, 2) immunohistochemistry to analyse both the terminal axonal sprouting in the muscles and the axon reaction within the nucleus of the facial nerve, the peripheral nerve, and its environment, and 3) digital motion analysis of the muscles. To obtain good functional facial nerve regeneration, a reduction of terminal sprouting in the mimic musculature seems to be more important than a reduction of collateral sprouting at the lesion site. Promising strategies include acceleration of nerve regeneration, forced induced use of the paralysed face, mechanical stimulation of the face, and transplantation of nerve-growth-promoting olfactory epithelium at the lesion site.

Establishment of an Efficient and Reproducible Regeneration System for Potato Cultivars Grown in Pakistan

International Nuclear Information System (INIS)

Iqbal, A.; Rizwan, A.; Mukhtar, Z.; Mansoor, S.; Asad, S.; Khalid, Z. M.

2016-01-01

The present study was carried out to assess the effect of growth regulators in three different combinations on mass propagation of currently grown three potato cultivars cv. Desiree, Kuroda and Cardinal. Varietal response on In vitro regeneration under different hormonal combinations. For callus induction, internodes of potato cultivars were cultured on modified Murashige and Skoog (MS) medium, added with different growth hormonal combinations. Callusing frequency for all these treatments and cultivars were recorded and in callus induction medium (CIM1) explants showed significantly higher callus formation as compared to two other combinations. For shoot induction, calli were cultured on Murashige and Skoog (MS) modified medium, supplemented with different hormonal combinations. Shoot induction medium (SIM3) gave best shoot induction frequency as compared to other media combinations. On the same media, an average number of shoots per explant were obtained for cultivar Desiree which is significantly different from the other two media combinations. Overall, the In vitro regeneration and multiplication potential was highest in the variety Cardinal followed by Kuroda and Desiree. The interaction between different hormonal combinations and varietal response for all the parameters showed significant differences. (author)

Plant regeneration from petiole segments of some species in tissue culture

Directory of Open Access Journals (Sweden)

Krystyna Klimaszewska

2013-12-01

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

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

Directory of Open Access Journals (Sweden)

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

In vitro regeneration of five wheat genotypes from immature zygotic embryos

International Nuclear Information System (INIS)

Khokhar, M.I.; Iqbal, M.Z.

2016-01-01

This study examined the ability to induce callus from immature zygotic embryos of five wheat genotypes (Lu 26, WH 543, Zamindar 80, BT-002 and Seher-06) in response to 2, 4 and 6 mg/L of 2,4-dichlorophenoxy acetic acid (2,4-D). Callus induction was most effective (41% averaged across the 5 genotypes) in the presence of 2 mg/L 2,4-D. Callus induction was highest in Lu 26 (34%) followed by WH 543 (33%). Highest percentage shoot formation (33%) from callus was possible on Murashige and Skoog (1962) medium containing 300 mg casein hydrolysate. BT-002 responded best to shoot formation (26%) followed by WH 543 (24%). Under these optimal conditions, callus could form within 7.4 days and shoots within 20.87 days (fastest growth averaged across the 5 genotypes). Zamindar-80 responded best by taking fewest days to initiate callus formation (7.88 days) while Lu 26 took the least amount of time to form shoots (23.25 days). This study provides a rapid and efficient, as well as cultivar-independent protocol for the indirect formation of shoots from callus, the first such report for WH 543, Zamindar 80, BT-002 and Seher-06. This protocol may be a useful protocol for transgenic wheat plants that are derived from the genetic transformation of callus, either by particle bombardment or Agrobacterium-mediated transformation, to produce, for example, insect- or herbicide-resistant plants, since a rapid and effective regeneration protocol is an essential first step for the successful regeneration of transgenic plants. (author)

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.

Strategic plans for the Hardwood Tree Improvement and Regeneration Center

Science.gov (United States)

Charles H. Michler; Keith E. Woeste

2002-01-01

The mission of the Hardwood Tree Improvement and Regeneration Center (HTIRC) at Purdue University is to advance the science of hardwood tree improvement and genomics in the central hardwood region of the United States by: developing and disseminating knowledge on improving the genetic quality of hardwood tree species; conserving fine hardwood germplasm; developing...

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 ...

A filter paper-based liquid culture system for citrus shoot organogenesis - a mixture-amount experiment

Science.gov (United States)

The objective of this study was to determine the effects of a static liquid culture system on shoot regeneration from citrus epicotyl explants. Two citrus types were used, Carrizo citrange and Ridge Pineapple sweet orange. A liquid culture system comprised of a Petri dish, cellulose filter paper dis...

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 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, ...

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.

Arabidopsis brassinosteroid biosynthetic mutant dwarf7-1 exhibits slower rates of cell division and shoot induction

Directory of Open Access Journals (Sweden)

Schulz Burkhard

2010-12-01

Full Text Available Abstract Background Plant growth depends on both cell division and cell expansion. Plant hormones, including brassinosteroids (BRs, are central to the control of these two cellular processes. Despite clear evidence that BRs regulate cell elongation, their roles in cell division have remained elusive. Results Here, we report results emphasizing the importance of BRs in cell division. An Arabidopsis BR biosynthetic mutant, dwarf7-1, displayed various characteristics attributable to slower cell division rates. We found that the DWARF4 gene which encodes for an enzyme catalyzing a rate-determining step in the BR biosynthetic pathways, is highly expressed in the actively dividing callus, suggesting that BR biosynthesis is necessary for dividing cells. Furthermore, dwf7-1 showed noticeably slower rates of callus growth and shoot induction relative to wild-type control. Flow cytometric analyses of the nuclei derived from either calli or intact roots revealed that the cell division index, which was represented as the ratio of cells at the G2/M vs. G1 phases, was smaller in dwf7-1 plants. Finally, we found that the expression levels of the genes involved in cell division and shoot induction, such as PROLIFERATING CELL NUCLEAR ANTIGEN2 (PCNA2 and ENHANCER OF SHOOT REGENERATION2 (ESR2, were also lower in dwf7-1 as compared with wild type. Conclusions Taken together, results of callus induction, shoot regeneration, flow cytometry, and semi-quantitative RT-PCR analysis suggest that BRs play important roles in both cell division and cell differentiation in Arabidopsis.

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 ...

beta-Blockade used in precision sports: effect on pistol shooting performance.

Science.gov (United States)

Kruse, P; Ladefoged, J; Nielsen, U; Paulev, P E; Sørensen, J P

1986-08-01

In a double-blind cross-over study of 33 marksmen (standard pistol, 25 m) the adrenergic beta 1-receptor blocker, metoprolol, was compared to placebo. Metoprolol obviously improved the pistol shooting performance compared with placebo. Shooting improved by 13.4% of possible improvement (i.e., 600 points minus actual points obtained) as an average (SE = 4%, 2P less than 0.002). The most skilled athletes demonstrated the clearest metoprolol improvement. We found no correlation between the shooting improvement and changes in the cardiovascular variables (i.e., changes of heart rate and systolic blood pressure) and no correlation to the estimated maximum O2 uptake. The shooting improvement is an effect of metoprolol on hand tremor. Emotional increase of heart rate and systolic blood pressure seem to be a beta 1-receptor phenomenon.

The Hardwood Tree Improvement and Regeneration Center: its strategic plans for sustaining the hardwood resource

Science.gov (United States)

Charles H. Michler; Michael J. Bosela; Paula M. Pijut; Keith E. Woeste

2003-01-01

A regional center for hardwood tree improvement, genomics, and regeneration research, development and technology transfer will focus on black walnut, black cherry, northern red oak and, in the future, on other fine hardwoods as the effort is expanded. The Hardwood Tree Improvement and Regeneration Center (HTIRC) will use molecular genetics and genomics along with...

Germination and plantlet regeneration of encapsulated microshoots of aromatic rice (Oryza sativa L. Cv. MRQ 74).

Science.gov (United States)

Taha, Rosna Mat; Saleh, Azani; Mahmad, Noraini; Hasbullah, Nor Azlina; Mohajer, Sadegh

2012-01-01

Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. In the present study, 3-5 mm microshoots of Oryza sativa L. Cv. MRQ 74 were used as explant sources for obtaining synthetic seeds. Microshoots were induced from stem explants on Murashige and Skoog (MS) medium supplemented with 1.5 mg/L benzylaminopurine (BAP). They were encapsulated in 3% (w/v) sodium alginate, 3% sucrose, 0.1 mg/L BAP, and 0.1 mg/L α-Naphthalene acetic acid (NAA). Germination and plantlet regeneration of the encapsulated seeds were tested by culturing them on various germination media. The effect of storage period (15-30 days) was also investigated. The maximum germination and plantlet regeneration (100.0%) were recorded on MS media containing 3% sucrose and 0.8% agar with and without 0.1 mg/L BAP. However, a low germination rate (6.67%) was obtained using top soil as a sowing substrate. The germination rate of the encapsulated microshoots decreased from 93.33% to 3.33% after 30 days of storage at 4°C in the dark. Therefore, further research is being done to improve the germination rate of the synthetic seeds.

Reality-based practice under pressure improves handgun shooting performance of police officers.

NARCIS (Netherlands)

Oudejans, R.R.D.

2008-01-01

The current study examined whether reality-based practice under pressure may help in preventing degradation of handgun shooting performance under pressure for police officers. Using a pre-post-test design, one group of nine police officers practised handgun shooting under pressure evoked by an

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

Rac1 selective activation improves retina ganglion cell survival and regeneration.

Directory of Open Access Journals (Sweden)

Erika Lorenzetto

Full Text Available In adult mammals, after optic nerve injury, retinal ganglion cells (RGCs do not regenerate their axons and most of them die by apoptosis within a few days. Recently, several strategies that activate neuronal intracellular pathways were proposed to prevent such degenerative processes. The rho-related small GTPase Rac1 is part of a complex, still not fully understood, intracellular signaling network, mediating in neurons many effects, including axon growth and cell survival. However, its role in neuronal survival and regeneration in vivo has not yet been properly investigated. To address this point we intravitreally injected selective cell-penetrating Rac1 mutants after optic nerve crush and studied the effect on RGC survival and axonal regeneration. We injected two well-characterized L61 constitutively active Tat-Rac1 fusion protein mutants, in which a second F37A or Y40C mutation confers selectivity in downstream signaling pathways. Results showed that, 15 days after crush, both mutants were able to improve survival and to prevent dendrite degeneration, while the one harboring the F37A mutation also improved axonal regeneration. The treatment with F37A mutant for one month did not improve the axonal elongation respect to 15 days. Furthermore, we found an increase of Pak1 T212 phosphorylation and ERK1/2 expression in RGCs after F37A treatment, whereas ERK1/2 was more activated in glial cells after Y40C administration. Our data suggest that the selective activation of distinct Rac1-dependent pathways could represent a therapeutic strategy to counteract neuronal degenerative processes in the retina.

Methodology of shooting training using modern IT techniques

Science.gov (United States)

Gudzbeler, Grzegorz; Struniawski, Jarosław

2017-08-01

Mastering, improvement, shaping and preservation of skills of safe, efficient and effective use of the firearm requires the use of relevant methodology of conducting the shooting training. However reality of police trainings does not usually allow for intensive training shooting with the use of ammunition. An alternative solution is the use of modern training technologies. Example of this is the "Virtual system of improvement tactics of intervention services responsible for security and shooting training." Introduction of stimulator to police trainings will enable complete stuff preparation to achieve its tasks, creating potential of knowledge and experience in many areas, far exceeding the capabilities of conventional training.

Characterization of somatic embryogenesis initiated from the Arabidopsis shoot apex.

Science.gov (United States)

Kadokura, Satoshi; Sugimoto, Kaoru; Tarr, Paul; Suzuki, Takamasa; Matsunaga, Sachihiro

2018-04-28

Somatic embryogenesis is one of the best examples of the remarkable developmental plasticity of plants, in which committed somatic cells can dedifferentiate and acquire the ability to form an embryo and regenerate an entire plant. In Arabidopsis thaliana, the shoot apices of young seedlings have been reported as an alternative tissue source for somatic embryos (SEs) besides the widely studied zygotic embryos taken from siliques. Although SE induction from shoots demonstrates the plasticity of plants more clearly than the embryo-to-embryo induction system, the underlying developmental and molecular mechanisms involved are unknown. Here we characterized SE formation from shoot apex explants by establishing a system for time-lapse observation of explants during SE induction. We also established a method to distinguish SE-forming and non-SE-forming explants prior to anatomical SE formation, enabling us to identify distinct transcriptome profiles of these two explants at SE initiation. We show that embryonic fate commitment takes place at day 3 of SE induction and the SE arises directly, not through callus formation, from the base of leaf primordia just beside the shoot apical meristem (SAM), where auxin accumulates and shoot-root polarity is formed. The expression domain of a couple of key developmental genes for the SAM transiently expands at this stage. Our data demonstrate that SE-forming and non-SE-forming explants share mostly the same transcripts except for a limited number of embryonic genes and root genes that might trigger the SE-initiation program. Thus, SE-forming explants possess a mixed identity (SAM, root and embryo) at the time of SE specification. Copyright © 2018. Published by Elsevier Inc.

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

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.

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 nickel on regeneration in Jatropha curcas L. and assessment of genotoxicity using RAPD markers

KAUST Repository

Sarkar, Tanmoy

2010-07-08

The aim of the present study was to determine the effect of nickel on shoot regeneration in tissue culture as well as to identify polymorphisms induced in leaf explants exposed to nickel through random amplified polymorphic DNA (RAPD). In vitro leaf explants of Jatropha curcas were grown in nickel amended Murashige and Skoog (MS) medium at four different concentrations (0, 0.01, 0.1, 1 mM) for 3 weeks. Percent regeneration, number of shoots produced and genotoxic effects were evaluated by RAPD using leaf explants obtained from the first three treatments following 5 weeks of their subsequent subculture in metal free MS medium. Percent regeneration decreased with increase in addition of nickel to the medium up to 14 days from 42.31% in control to zero in 1.0 mM. The number of shoot buds scored after 5 weeks was higher in control as compared to all other treatments except in one of the metal free subculture medium wherein the shoot number was higher in 0.01 mM treatment (mean = 7.80) than control (mean = 7.60). RAPD analysis produced only 5 polymorphic bands (3.225%) out of a total of 155 bands from 18 selected primers. Only three primers OPK-19, OPP-2, OPN-08 produced polymorphic bands. The dendrogram showed three groups A, B, and C. Group A samples showed 100% genetic similarity within them. Samples between groups B and C were more genetically distant from each other as compared to samples between groups A and B as well as groups A and C. Cluster analysis based on RAPD data correlated with treatments. © 2010 Springer Science+Business Media, LLC.

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.

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).

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)

Germination and Plantlet Regeneration of Encapsulated Microshoots of Aromatic Rice (Oryza sativa L. Cv. MRQ 74

Directory of Open Access Journals (Sweden)

Rosna Mat Taha

2012-01-01

Full Text Available Plant tissues such as somatic embryos, apical shoot tips, axillary shoot buds, embryogenic calli, and protocom-like bodies are potential micropropagules that have been considered for creating synthetic seeds. In the present study, 3–5 mm microshoots of Oryza sativa L. Cv. MRQ 74 were used as explant sources for obtaining synthetic seeds. Microshoots were induced from stem explants on Murashige and Skoog (MS medium supplemented with 1.5 mg/L benzylaminopurine (BAP. They were encapsulated in 3% (w/v sodium alginate, 3% sucrose, 0.1 mg/L BAP, and 0.1 mg/L α-Naphthalene acetic acid (NAA. Germination and plantlet regeneration of the encapsulated seeds were tested by culturing them on various germination media. The effect of storage period (15–30 days was also investigated. The maximum germination and plantlet regeneration (100.0% were recorded on MS media containing 3% sucrose and 0.8% agar with and without 0.1 mg/L BAP. However, a low germination rate (6.67% was obtained using top soil as a sowing substrate. The germination rate of the encapsulated microshoots decreased from 93.33% to 3.33% after 30 days of storage at 4°C in the dark. Therefore, further research is being done to improve the germination rate of the synthetic seeds.

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....

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.

RAPD analysis of mutants obtained by ion beam irradiation to hinoki cypress shoot primordia

International Nuclear Information System (INIS)

Ishii, K.; Yamada, Y.; Hase, Y.; Shikazono, N.; Tanaka, A.

2003-01-01

Mutants were induced by irradiation of the shoot primordia of Hinoki cypress with 50 MeV 4 He 2+ heavy ion beam. Fresh shoot primordia on the CD medium in the plastic Petri dish (35 x 10 mm) were irradiated. Xanta mutants were induced from 38 to 266 Gy irradiation. Waxy mutants were induced from 76 to 266 Gy irradiation. Xanta, waxy and control type of regenerated Hinoki cypress in vitro were checked for their DNA level difference using RAPD analysis. Among 81 primers used, 23 primers produced the 68 bands. Among them stable 44 bands produced by 15 primers were compared between mutants and control plant. So far, there is no variation among the RAPD analysis band patterns of those mutants. Bigger test size may detect the gene variation specific for mutants

Regeneration of three sweet potato (Ipomea batatas (L.)) accessions via meristem, Nodal and callus induction

International Nuclear Information System (INIS)

Addae-Frimpomaah, F.

2012-11-01

In vitro regeneration of three sweet potato accessions UE007, UK-BNARI and SA-BNARI using meristem, nodal cuttings or callus induction was studied. Meristematic explants cultured on Murashige and Skoog (1962) basal medium supplemented with low concentration of benzylaminopurine (BAP) or kinetin resulted in callus with or without shoot development which delayed shoot emergence. The degree of callus development increased as the concentration of the cytokinin in the culture medium increased. Although, callus development was comparatively lower on kinetin amended medium than BAP amended medium, Murashige and Skoog medium supplemented with 0.25mg/1BAP had the highest shoot induction (80%). For further differentiation of callus or shoots into distinct stem and leaves, the culture were transferred into fresh MS medium supplemented with 0.25mg/1 BAP, 0.1 mg/1 NAA and 0.1 mg/1 Gibberellic acid (GA 3 . To overcome the delay in shoot initiation using meristem culture, nodal cuttings of sweet potato were used as explants and cultured on MS medium amended with 0.3 - 0.9mg/1 BAP. All explants cultured on 0.3 or 0.6mg/1 BAP developed shoots. Furthermore, liquid MS medium amended with 0.25mg/1 BAP, 0.1mg/I NAA, and 0.1mg/1 GA 3 also enhanced early shoot development from nodal cutting explants compared to solid culture. Post flask acclimatisation of meristem or nodal cutting-derived plantlets showed that meristem derived plantlets were better acclimatised than nodal cutting plants due to vigorous root development leading to higher percentage survival in pots and subsequent tuber production. Callusogenesis was achieved when leaf lobe explants were cultured on CLC/ Ipomoea medium supplemented with 1.0 - 4.0mg/1 2,4-D with 4.0mg/1 2,4-D being the optimal concentration. However, the calli were non-embryogenic and therefore could not produce embryos when transferred to 0.1mg/1 BAP amended medium but rather produced either single or multiple shoots. The highest percentage shoot (83

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.

Sirococcus Shoot Blight

Science.gov (United States)

Thomas H. Nicholls; Kathryn Robbins

1984-01-01

Sirococcus shoot blight, caused by the fungus Sirococcus strobilinus Preuss, affects conifers in the Northern United States and southern Canada. The fungus infects the new shoots; diseased seedlings and saplings are especially affected. In the United States, sirococcus shoot blight has become increasingly widespread since the early 1970's. When favorable...

In vitro regeneration from petiole explants of non-toxic Jatropha curcas

KAUST Repository

Kumar, Nitish

2011-01-01

Jatropha curcas, a multipurpose shrub has acquired significant economic potential as biodiesel plant. The seeds or pressed cake is toxic due to the presence of toxic substances and is not useful as food/fodder despite having the best protein composition. A simple, efficient, and reproducible method for plant regeneration through direct organogenesis from petiole explants of non-toxic J. curcas was developed using Murashige and Skoog (MS) medium supplemented with different concentrations of thidiazuron (TDZ). The best induction of shoot buds (57.61%), and number of shoot buds (4.98) per explant were obtained when in vitro petiole explants were placed horizontally on MS medium supplemented with 2.27 mu M TDZ. The Induced shoot buds were transferred to MS medium containing 10 mu M kinetin (Kn), 4.5 mu M 6-benzyl aminopurine (BA), and 5.5 mu M alpha-naphthaleneacetic acid (NAA) for shoot proliferation and subsequent elongation was achieved on MS medium supplemented with 2.25 mu M BA and 8.5 mu M IAA. The elongated shoots could be rooted on half-strength MS medium with 15 mu M IBA, 11.4 mu M IAA and 5.5 mu M NAA with more than 90% survival rate. (C) 2010 Elsevier B.V. All rights reserved.

Virus immobilization on biomaterial scaffolds through biotin-avidin interaction for improving bone regeneration.

Science.gov (United States)

Hu, Wei-Wen; Wang, Zhuo; Krebsbach, Paul H

2016-02-01

To spatially control therapeutic gene delivery for potential tissue engineering applications, a biotin-avidin interaction strategy was applied to immobilize viral vectors on biomaterial scaffolds. Both adenoviral vectors and gelatin sponges were biotinylated and avidin was applied to link them in a virus-biotin-avidin-biotin-material (VBABM) arrangement. The tethered viral particles were stably maintained within scaffolds and SEM images illustrated that viral particles were evenly distributed in three-dimensional (3D) gelatin sponges. An in vivo study demonstrated that transgene expression was restricted to the implant sites only and transduction efficiency was improved using this conjugation method. For an orthotopic bone regeneration model, adenovirus encoding BMP-2 (AdBMP2) was immobilized to gelatin sponges before implanting into critical-sized bone defects in rat calvaria. Compared to gelatin sponges with AdBMP2 loaded in a freely suspended form, the VBABM method enhanced gene transfer and bone regeneration was significantly improved. These results suggest that biotin-avidin immobilization of viral vectors to biomaterial scaffolds may be an effective strategy to facilitate tissue regeneration. Copyright © 2013 John Wiley & Sons, Ltd.

Improved modelling of a parallel plate active magnetic regenerator

International Nuclear Information System (INIS)

Engelbrecht, K; Nielsen, K K; Bahl, C R H; Tušek, J; Kitanovski, A; Poredoš, A

2013-01-01

Much of the active magnetic regenerator (AMR) modelling presented in the literature considers only the solid and fluid domains of the regenerator and ignores other physical effects that have been shown to be important, such as demagnetizing fields in the regenerator, parasitic heat losses and fluid flow maldistribution in the regenerator. This paper studies the effects of these loss mechanisms and compares theoretical results with experimental results obtained on an experimental AMR device. Three parallel plate regenerators were tested, each having different demagnetizing field characteristics and fluid flow maldistributions. It was shown that when these loss mechanisms are ignored, the model significantly over predicts experimental results. Including the loss mechanisms can significantly change the model predictions, depending on the operating conditions and construction of the regenerator. The model is compared with experimental results for a range of fluid flow rates and cooling loads. (paper)

Branch architecture in Ginkgo biloba: wood anatomy and long shoot-short shoot interactions.

Science.gov (United States)

Little, Stefan A; Jacobs, Brooke; McKechnie, Steven J; Cooper, Ranessa L; Christianson, Michael L; Jernstedt, Judith A

2013-10-01

Ginkgo, centrally placed in seed plant phylogeny, is considered important in many phylogenetic and evolutionary studies. Shoot dimorphism of Ginkgo has been long noted, but no work has yet been done to evaluate the relationships between overall branch architecture and wood ring characters, shoot growth, and environmental conditions. • Branches, sampled from similar canopy heights, were mapped with the age of each long shoot segment determined by counting annual leaf-scar series on its short shoots. Transverse sections were made for each long shoot segment and an adjacent short shoot; wood ring thickness, number of rings, and number of tracheids/ring were determined. Using branch maps, we identified wood rings for each long shoot segment to year and developmental context of each year (distal short shoot growth only vs. at least one distal long shoot). Climate data were also analyzed in conjunction with developmental context. • Significantly thicker wood rings occur in years with distal long shoot development. The likelihood that a branch produced long shoots in a given year was lower with higher maximum annual temperature. Annual maximum temperature was negatively correlated with ring thickness in microsporangiate trees only. Annual minimum temperatures were correlated differently with ring thickness of megasporangiate and microsporangiate trees, depending on the developmental context. There were no significant effects associated with precipitation. • Overall, developmental context alone predicts wood ring thickness about as well as models that include temperature. This suggests that although climatic factors may be strongly correlated with wood ring data among many gymnosperm taxa, at least for Ginkgo, correlations with climate data are primarily due to changes in proportions of shoot developmental types (LS vs. SS) across branches.

Effect of Plant Growth Regulators on a Shoot and Root Formation from the Leaf and Flower Culture of a Standard-type Chrysanthemum 'Jinba'

International Nuclear Information System (INIS)

Lee, J.S.; Lee, G.J.; Chung, S.J.; Kim, J.B.; Kim, D.S.; Kang, S.Y.

2008-01-01

In this study we investigated the conditions of a higher frequency for regenerated plants from different explants of a standard-type chrysanthemum 'Jinba'. In vitro culture was initiated on an MS medium containing 3% sucrose, 0.8% agar, and 5 μM benzyl adenine (BA) with naphthalene acetic acid (NAA) by using surface-sterilized leaf and flower tissues from greenhouse-grown plants. Direct shoot regeneration from the leaf and flower explants was obtained 21 to 28 days after the initial culture. Among the seven combinations of the growth regulators used for the culture, the most efficient condition for the shoot and root formation from the leaf tissue was obtained when the MS basic medium was supplemented with 0.5 mg L-¹ BA and 1.0 mg L-¹ NAA, and 0.1 mg L-¹ BA and 0.5 mg L-¹ NAA, while the culture using floret tissues was most efficient on the medium supplemented with 0.5 mg L-¹ BA and 0.5 mg L-¹ NAA, and 0.1 mg L-¹ BA and 1.0 mg L-¹ NAA. These results will provide valuable information to help set up an efficient system for a tissue culture of chrysanthemum cv. Jinba to improve one or some of its negative traits in combination with a radiation mutagenesis approach

In vitro mass propagation of Salvia canariensis by axillary shoots

Directory of Open Access Journals (Sweden)

Sebastiana Mederos Molina

2014-01-01

Full Text Available During the establishment of shoots of Salvia canariensis L., five environmental factor treatments were applied. For each axillary node two shoots grew well when explants were incubated at continued ligth for 15 days followed by 16 hrs photoperiod by 30 days. Shoots multiplication was improved on a modified Murashige and Skoog (MS (1962 medium - MS + 825 mg/l NH4NO3 - supplemented with 10-7 M BA and 10-7 M NAA. The shoots produced well developed root systems within three weeks after transfer to the same culture medium supplemented with 5x 10-7 M NAA.

Rosette growth of shoots in chrysanthemum (Dendranthema grandiflora Tzvelev) as a result of in vitro propagation of plants and gamma irradiation used for mutation induction

International Nuclear Information System (INIS)

Jerzy, M.; Zalewska, M.; Lema, J.

1999-01-01

Rosette growth of chrysanthemum shoots in 'Mrs. R.C. Puling' was observed after in vitro propagation with explants obtained from vernalised and non-vernalised stock plants. The phenomenon was also observed as a result of the exposure of leaf explants to gamma radiation used for in vitro regeneration of plants in mutation induction. The higher the irradiation dose, the more considerable the rosette growth. Following the 4th pinching of shoot tips, only elongating growth of plants was observed

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....

Which stem parts of Slender speedwell (Veronica filiformis) are the most successful in plant regeneration?

Czech Academy of Sciences Publication Activity Database

Šerá, Božena

2012-01-01

Roč. 67, č. 1 (2012), s. 110-115 ISSN 0006-3088 R&D Projects: GA MŠk OC10032 Institutional research plan: CEZ:AV0Z60870520 Keywords : clonal * invasive species * regeneration * shoot * stem * terminal * vegetative reproduciton Subject RIV: EF - Botanics Impact factor: 0.506, year: 2012

Q-factor improvement of degenerate four-wave-mixing regenerators for ASE degraded signals

Science.gov (United States)

Lu, Hang; Wu, Bao-jian; Geng, Yong; Zhou, Xing-yu; Sun, Fan

2017-11-01

All-optical regenerators can be used to suppress amplified spontaneous emission (ASE) noise introduced by cascaded erbium doped fiber amplifiers (EDFAs) in optical fiber communication systems and lead to the improvement of optical receiver sensitivity. By introducing the Q-factor transfer function (QTF), we evaluate the Q-factor performance of degenerate four-wave mixing (DFWM) regenerators with clock pump and reveal the differences between the optimal input powers determined from the static and dynamic power tranfer function (PTF) and the QTF curves. Our simulation shows that the clock-pump regnerator is capable of improving the Q-facor and receiver sensitivity for 40 Gbit/s ASE-degraded return-to-zero on-off keying (RZ-OOK) signal by 2.58 dB and 4.2 dB, respectively.

Local delivery of glial cell line-derived neurotrophic factor improves facial nerve regeneration after late repair.

Science.gov (United States)

Barras, Florian M; Kuntzer, Thierry; Zurn, Anne D; Pasche, Philippe

2009-05-01

Facial nerve regeneration is limited in some clinical situations: in long grafts, by aged patients, and when the delay between nerve lesion and repair is prolonged. This deficient regeneration is due to the limited number of regenerating nerve fibers, their immaturity and the unresponsiveness of Schwann cells after a long period of denervation. This study proposes to apply glial cell line-derived neurotrophic factor (GDNF) on facial nerve grafts via nerve guidance channels to improve the regeneration. Two situations were evaluated: immediate and delayed grafts (repair 7 months after the lesion). Each group contained three subgroups: a) graft without channel, b) graft with a channel without neurotrophic factor; and c) graft with a GDNF-releasing channel. A functional analysis was performed with clinical observation of facial nerve function, and nerve conduction study at 6 weeks. Histological analysis was performed with the count of number of myelinated fibers within the graft, and distally to the graft. Central evaluation was assessed with Fluoro-Ruby retrograde labeling and Nissl staining. This study showed that GDNF allowed an increase in the number and the maturation of nerve fibers, as well as the number of retrogradely labeled neurons in delayed anastomoses. On the contrary, after immediate repair, the regenerated nerves in the presence of GDNF showed inferior results compared to the other groups. GDNF is a potent neurotrophic factor to improve facial nerve regeneration in grafts performed several months after the nerve lesion. However, GDNF should not be used for immediate repair, as it possibly inhibits the nerve regeneration.

Rapid in vitro propagation system through shoot tip cultures of Vitex trifolia L.-an important multipurpose plant of the Pacific traditional Medicine.

Science.gov (United States)

Ahmed, Rafique; Anis, Mohammad

2014-07-01

A rapid and efficient plant propagation system through shoot tip explants was established in Vitex trifolia L., a medicinally important plant belonging to the family Verbenaceae. Multiple shoots were induced directly on Murashige and Skoog (MS) medium consisting of different cytokinins, 6-benzyladenine (BA), kinetin (Kin) and 2-isopentenyl adenine (2-iP), BA at an optimal concentration of 5.0 μM was most effective in inducing multiple shoots where 90 % explants responded with an average shoot number (4.4±0.1) and shoot length (2.0±0.1 cm) after 6 weeks of culture. Inclusion of NAA in the culture medium along with the optimum concentration of BA promoted a higher rate of shoot multiplication and length of the shoot, where 19.2±0.3 well-grown healthy shoots with an average shoot length of 4.4±0.1 cm were obtained on completion of 12 weeks culture period. Ex vitro rooting was achieved best directly in soilrite when basal portion of the shoots were treated with 500 μM indole-3-butyric acid for 15 min which was the most effective in inducing roots, as 95 % of the microshoots produced roots. Plantlets went through a hardening phase in a controlled plant growth chamber, prior to ex-vitro transfer. Micropropagated plants grew well, attained maturity and flowered with 92 % survival rate. The results of this study provide the first report on in vitro plant regeneration of Vitex trifolia L. using shoot tip explants.

Improvement of thermal regeneration of spent granular activated carbon using air agent : Application of sintering and deoxygenation

International Nuclear Information System (INIS)

Cho, Joon-Hyung; Jeon, Soo-Bin; Oh, Kwang-Joong; Kim, Yoon-Su; Seo, Jong-Beom; Jung, Jong-Hyeon

2014-01-01

Thermal regeneration of spent granular activated carbon (GAC) using sintering, air-activation, and deoxygenation was investigated to determine the potential of this method for overcoming the drawbacks of thermal regeneration. The conditions for each step were optimized. The physicochemical properties of four regenerated GACs were assessed using BET, SEM, and FT-IR analysis. The suitability of the regenerated GACs for liquid-phase applications was assessed by phenol adsorption, using adsorption isotherms, kinetics, and thermodynamics. Sintering increased the micropore area and volume of regenerated GAC by 19% and 16%, respectively, and controlled excessive burn-off, reducing it by 19%. Air-activation has economic advantages because the reaction time is 80% less than that for steam activation. Deoxygenation improved the maximum adsorption capacity by 7%, although the number of micropores was reduced. Regenerated GAC by sintering, air-activation, and deoxygenation was best for liquid-phase applications; the results show that these steps help to overcome the drawbacks of thermal regeneration

Improvement of thermal regeneration of spent granular activated carbon using air agent : Application of sintering and deoxygenation

Energy Technology Data Exchange (ETDEWEB)

Cho, Joon-Hyung; Jeon, Soo-Bin; Oh, Kwang-Joong [Pusan National University, Busan (Korea, Republic of); Kim, Yoon-Su [Kolon Global Corporation, Gwacheon (Korea, Republic of); Seo, Jong-Beom [HyunDai Steel Company, Dangjin (Korea, Republic of); Jung, Jong-Hyeon [Daegu Haany University, Gyeongsan (Korea, Republic of)

2014-09-15

Thermal regeneration of spent granular activated carbon (GAC) using sintering, air-activation, and deoxygenation was investigated to determine the potential of this method for overcoming the drawbacks of thermal regeneration. The conditions for each step were optimized. The physicochemical properties of four regenerated GACs were assessed using BET, SEM, and FT-IR analysis. The suitability of the regenerated GACs for liquid-phase applications was assessed by phenol adsorption, using adsorption isotherms, kinetics, and thermodynamics. Sintering increased the micropore area and volume of regenerated GAC by 19% and 16%, respectively, and controlled excessive burn-off, reducing it by 19%. Air-activation has economic advantages because the reaction time is 80% less than that for steam activation. Deoxygenation improved the maximum adsorption capacity by 7%, although the number of micropores was reduced. Regenerated GAC by sintering, air-activation, and deoxygenation was best for liquid-phase applications; the results show that these steps help to overcome the drawbacks of thermal regeneration.

Development of an efficient regeneration protocol for three genotypes of brassica juncea

International Nuclear Information System (INIS)

Bano, R.; Khan, M.H.; Rashid, H.

2010-01-01

Two phytohormones, auxins (Naphthalene acetic acid and Indole acetic acid) and cytokinins (Benzyl aminopurine and Kinetin) with concentrations were used to develop an efficient regeneration protocol for 3 genotypes of Brassica juncea (UCD-635, RL-18 and NIFA RAYE). The explants were cultured on MS-medium supplemented with BAP 1.0 mgL/sup -1//NAA 0.1 mgL-1, BAP 2.0 mg L/sup -1//NAA 0.2 mg L/sup -1/, BAP 3.0 mgL/sup -1/ NAA 0.3 mg L-1 and Kinetin 1.0 mg L/sup -1/ IAA 0.1 mg L/sup -1/, Kinetin 2.0 mg L/sup -1//IAA 0.2 mg L/sup -1/, Kinetin 3.0mg L-1/IAA 0.3 mg L/sup -1/. Maximum callus production (65.55) was observed on MS medium containing with BAP 2.0 mgL-1/NAA 0.2 mg L/sup -1/. Maximum shooting (22.31) was observed BAP 3.0 mg L/sup -1//NAA 0.3 mg L/sup -1/ and KIN 3.0 mg L-1/IAA 0.3 mg L/sup -1/. Regeneration efficiency was found maximum (7.13) with BAP 3.0 mg L/sup -1//NAA 0.3 mg L/sup -1/. The three genotypes were found significantly different at p greater or equal to 0.05 in shoots production and regeneration efficiency. (author)

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.

Successful micropropagation of the cadmium hyperaccumulator Viola baoshanensis (Violaceae).

Science.gov (United States)

Li, Jin-Tian; Deng, Dong-Mei; Peng, Guang-Tian; Deng, Jin-Chuan; Zhang, Jun; Liao, Bin

2010-01-01

Viola baoshanensis is one of the most rare cadmium (Cd) hyperaccumulators, however, it is hard to propagate. Micropropagation has been applied to solve the problems with propagation of a few heavy metal hyperaccumulators. Therefore there is a high likelihood that micropropagation may offer a suitable method for large-scale propagation of V. baoshanensis To test this hypothesis, three types of explants were used for shoot regeneration and various combinations of four plant growth regulators were used to improve shoot regeneration efficiency from leaflet of V. baoshanensis. Best shoot regeneration efficiency was obtained by incubating leaflet in a 1/2 MS medium supplemented with 2.5 oM BA + 2.5 microM IBA, therein shoot regeneration rate was 70.9% and the number of shoots formation per explant was 22.4. Rooting was achieved from almost all regenerated shoot growing on 1/2 MS medium without plant growth regulator. Micropropagated seedlings were acclimatized under greenhouse conditions and 95% of them survived and showed no visible morphological variation compared to their donor plant. Furthermore, there were no significant differences between regenerated and seed-germinated V. baoshanensis in Cd tolerance and accumulation. These results suggested that an efficient and rapid micropropogation system was successfully developed for V. baoshanensis.

Resposta à regeneração e crescimento de brotos in vitro de Kielmeyera coriacea quando influenciado por diferentes concentrações dos sais e de sacarose In vitro regeneration and growth response of Kielmeyera coriacea shoots when affected by salts and sucrose concentrations

Directory of Open Access Journals (Sweden)

José Eduardo Brasil Pereira Pinto

1996-04-01

Full Text Available Avaliaram-se diferentes concentrações de sacarose e sais do MS (MURASHIGE & SKOOG, J 962 na regeneração e crescimento de brotos de Kielmeyera coriacea in vitro. A redução e o aumento da quantidade de sacarose partindo de 30 e 45g/L, respectivamente, causou um decréscimo no número total de brotos. O uso integral ou da metade das concentrações dos sais do MS proporcionou maiores taxas de multiplicação. A maior porcentagem de brotos com mais de 1,0cm de comprimento pôde ser obtida empregando-se 30 g/l de sacarose associado a concentração 1/1 do MS. A porcentagem média de brotos decresceu linearmente com a diluição salina.Trials were carried out to test sucrose and salt concentrations added to growth medium on regeneration and growth response of Kielmeyera coriacea shoots. The reduction and increase of sucrose of 30 and 45g/l, rerspectively, caused a decrease in total number of shoots. A higher shoots percentage of with more than 1.0cm, occurred on media with 30g/L of sucrose. The use of total force (1/1 and half strength (1/2 of MS salt proportioned a higher shoot ratio and growth.

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.

Effect of gamma irradiation on Callus formation and regeneration of wheat immature embryos

International Nuclear Information System (INIS)

Saleh, O.M.

2007-01-01

Four Egyptian bread wheat cultivars; G164, G168, SK61 and Sids1, were tested for their response to six gamma irradiation treatments; 1, 2, 3 Gy (as low doses) and 10, 20, 30 Gy (as high doses) in addition to 0 Gy (as a control) in terms of callus formation and regeneration of immature embryos. Low doses of gamma irradiations ( 1, 2 and 3 Gy) showed favourable effects on both traits; number of regenerated calli and number of shoots per callus comparing with the control (0 Gy), while high doses; 10, 20 and 30 Gy, had the worst effect comparing with the control (0 Gy). G164 cultivar was shown to get the best response in terms of callus formation and regeneration when exposed to low doses of gamma irradiation. In conclusion, gamma irradiation can serve in increasing regeneration efficiency of Egyptian bread wheat cells when used in low doses

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)

Exposure to lead in South African shooting ranges

International Nuclear Information System (INIS)

Mathee, Angela; Jager, Pieter de; Naidoo, Shan; Naicker, Nisha

2017-01-01

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

Exposure to lead in South African shooting ranges

Energy Technology Data Exchange (ETDEWEB)

Mathee, Angela [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg (Environmental Health Department, Faculty of Health Sciences), PO Box 524, Auckland Park, Johannesburg 2006 (South Africa); Jager, Pieter de [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); National Health Laboratory Service (Epidemiology and Surveillance Unit, National Institute for Occupational Health), PO Box 4788, Johannesburg 2000 (South Africa); Naidoo, Shan [University of the Witwatersrand (School of Public Health), PO Box Wits, Johannesburg 2050 (South Africa); Naicker, Nisha [South African Medical Research Council, Environment & Health Research Unit, PO Box 87373, Houghton 2041 (South Africa); University of the Witwatersrand, School of Public Health, PO Box Wits, Johannesburg 2050 (South Africa); University of Johannesburg, Environmental Health Department, Faculty of Health Sciences, PO Box 524, Auckland Park, Johannesburg 2006 (South Africa)

2017-02-15

Introduction: Lead exposure in shooting ranges has been under scrutiny for decades, but no information in this regard is available in respect of African settings, and in South Africa specifically. The aim of this study was to determine the blood lead levels in the users of randomly selected private shooting ranges in South Africa's Gauteng province. Methods: An analytical cross sectional study was conducted, with participants recruited from four randomly selected shooting ranges and three archery ranges as a comparator group. Results: A total of 118 (87 shooters and 31 archers) were included in the analysis. Shooters had significantly higher blood lead levels (BLL) compared to archers with 36/85 (42.4%) of shooters versus 2/34 (5.9%) of archers found to have a BLL ≥10 μg/dl (p<0.001). Conclusion: Shooting ranges may constitute an import site of elevated exposure to lead. Improved ventilation, low levels of awareness of lead hazards, poor housekeeping, and inadequate personal hygiene facilities and practices at South African shooting ranges need urgent attention. - Highlights: • This is the first study, to our knowledge, of lead exposure in shooting ranges in an African setting. • This study indicates highly elevated lead exposure amongst the users of certain private shooting ranges in South Africa. • Lead exposure may be a serious, yet under-studied, source of adult lead exposure in South Africa, and possibly elsewhere on the African continent.

Brief electrical stimulation improves nerve regeneration after delayed repair in Sprague Dawley rats.

Science.gov (United States)

Elzinga, Kate; Tyreman, Neil; Ladak, Adil; Savaryn, Bohdan; Olson, Jaret; Gordon, Tessa

2015-07-01

Functional recovery after peripheral nerve injury and surgical repair declines with time and distance because the injured neurons without target contacts (chronic axotomy) progressively lose their regenerative capacity and chronically denervated Schwann cells (SCs) atrophy and fail to support axon regeneration. Findings that brief low frequency electrical stimulation (ES) accelerates axon outgrowth and muscle reinnervation after immediate nerve surgery in rats and human patients suggest that ES might improve regeneration after delayed nerve repair. To test this hypothesis, common peroneal (CP) neurons were chronically axotomized and/or tibial (TIB) SCs and ankle extensor muscles were chronically denervated by transection and ligation in rats. The CP and TIB nerves were cross-sutured after three months and subjected to either sham or one hour 20Hz ES. Using retrograde tracing, we found that ES significantly increased the numbers of both motor and sensory neurons that regenerated their axons after a three month period of chronic CP axotomy and/or chronic TIB SC denervation. Muscle and motor unit forces recorded to determine the numbers of neurons that reinnervated gastrocnemius muscle demonstrated that ES significantly increased the numbers of motoneurons that reinnervated chronically denervated muscles. We conclude that electrical stimulation of chronically axotomized motor and sensory neurons is effective in accelerating axon outgrowth into chronically denervated nerve stumps and improving target reinnervation after delayed nerve repair. Possible mechanisms for the efficacy of ES in promoting axon regeneration and target reinnervation after delayed nerve repair include the upregulation of neurotrophic factors. Copyright © 2015 Elsevier Inc. All rights reserved.

Photosynthesis of a scots pine shoot: the effect of shoot inclination on the photosynthetic response of a shoot subjected to direct radiation

International Nuclear Information System (INIS)

Oker-Blom, P.; Kellomaki, S.; Smolander, H.

1983-01-01

A set of photosynthetic responses of a Scots pine (Pinus sylvestris L.) shoot to light was derived from the shoot geometry and the photosynthetic response of a single needle. Computations showed that the shape of the photosynthesis light-curves varies substantially depending on the direction of radiation relative to the shoot position. Differences in the initial and maximum rates of photosynthesis were due to changes in the effective projection area and the irradiated fraction of the shoot, respectively

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.

Shoot differentiation from protocorm callus cultures of Vanilla planifolia (Orchidaceae): proteomic and metabolic responses at early stage.

Science.gov (United States)

Palama, Tony L; Menard, Patrice; Fock, Isabelle; Choi, Young H; Bourdon, Emmanuel; Govinden-Soulange, Joyce; Bahut, Muriel; Payet, Bertrand; Verpoorte, Robert; Kodja, Hippolyte

2010-05-05

Vanilla planifolia is an important Orchid commercially cultivated for the production of natural vanilla flavour. Vanilla plants are conventionally propagated by stem cuttings and thus causing injury to the mother plants. Regeneration and in vitro mass multiplication are proposed as an alternative to minimize damage to mother plants. Because mass production of V. planifolia through indirect shoot differentiation from callus culture is rare and may be a successful use of in vitro techniques for producing somaclonal variants, we have established a novel protocol for the regeneration of vanilla plants and investigated the initial biochemical and molecular mechanisms that trigger shoot organogenesis from embryogenic/organogenic callus. For embryogenic callus induction, seeds obtained from 7-month-old green pods of V. planifolia were inoculated on MS basal medium (BM) containing TDZ (0.5 mg l(-1)). Germination of unorganized mass callus such as protocorm -like structure (PLS) arising from each seed has been observed. The primary embryogenic calli have been formed after transferring on BM containing IAA (0.5 mg l(-1)) and TDZ (0.5 mg l(-1)). These calli were maintained by subculturing on BM containing IAA (0.5 mg l(-1)) and TDZ (0.3 mg l(-1)) during 6 months and formed embryogenic/organogenic calli. Histological analysis showed that shoot organogenesis was induced between 15 and 20 days after embryogenic/organogenic calli were transferred onto MS basal medium with NAA (0.5 mg l(-1)). By associating proteomics and metabolomics analyses, the biochemical and molecular markers responsible for shoot induction have been studied in 15-day-old calli at the stage where no differentiating part was visible on organogenic calli. Two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization time-of-flight-tandem mass spectrometry (MALDI-TOF-TOF-MS) analysis revealed that 15 protein spots are significantly expressed (P tissue culture, phenolic compounds such

School Shootings and Student Performance

OpenAIRE

Panu Poutvaara; Olli Ropponen

2010-01-01

In this paper, we study how high school students reacted to the shocking news of a school shooting. The shooting coincided with national high-school matriculation exams. As there were exams both before and after the shooting, we can use a difference-in-differences analysis to uncover how the school shooting affected the test scores compared to previous years. We find that the average performance of young men declined due to the school shooting, whereas we do not observe a similar pattern for ...

Introduction of ROL genes in Rosa Hybrida L. for improved rootstock performance

Energy Technology Data Exchange (ETDEWEB)

Van der Salm, T.P.M.

1996-06-04

We aim to improve the performance of combination plants of rose by genetic modification of its root stock, with special reference to their performance at low energy conditions. The first objective of this research was the introduction of the ROL genes from A. rhizogenes in the recalcitrant species rose. For this purpose the rose root stock `Money way` was used. The second objective was to determine the effects of these genes on the rooting characteristics of root stock plants and their influence on the growth performance of combination plants. Special attention had to be paid to methodological aspects such as micropropagation, transformation and regeneration. First, the medium composition was optimized for the in vitro culture of root stock `Money way`. The effect of ROL genes on the formation of adventitious roots was described. It was shown that the formation of kanamycin resistant roots was stimulated by ROL genes, especially by a combination of ROLA, B and C. A regeneration method was developed, in which shoots were regenerated from excised roots via somatic embryogenesis. This regeneration method was applied for the regeneration of transformed shoots from kanamycin resistant roots, especially from those with the ROLB gene or a combination of ROLA, B and C genes. As a result several transformed plants were obtained. Expression patterns of the ROL genes were correlated with the phenotypical characteristics of the transformed rose plants. In order to determine the effect of ROL genes on the growth and development of a scion, combination plants were made, consisting of the root system of a transgenic root stock and the aerial parts of the cultivar `Madelon`. For evaluation of the effects of ROL genes on root stock performance and energy efficiency, the combination plants were studied under climate room conditions at 15 and 20 deg C. Finally, an overview is given of the possible applications of ROL genes for crop improvement.

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

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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.

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.

GPU based numerical simulation of core shooting process

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Yi-zhong Zhang

2017-11-01

Full Text Available Core shooting process is the most widely used technique to make sand cores and it plays an important role in the quality of sand cores. Although numerical simulation can hopefully optimize the core shooting process, research on numerical simulation of the core shooting process is very limited. Based on a two-fluid model (TFM and a kinetic-friction constitutive correlation, a program for 3D numerical simulation of the core shooting process has been developed and achieved good agreements with in-situ experiments. To match the needs of engineering applications, a graphics processing unit (GPU has also been used to improve the calculation efficiency. The parallel algorithm based on the Compute Unified Device Architecture (CUDA platform can significantly decrease computing time by multi-threaded GPU. In this work, the program accelerated by CUDA parallelization method was developed and the accuracy of the calculations was ensured by comparing with in-situ experimental results photographed by a high-speed camera. The design and optimization of the parallel algorithm were discussed. The simulation result of a sand core test-piece indicated the improvement of the calculation efficiency by GPU. The developed program has also been validated by in-situ experiments with a transparent core-box, a high-speed camera, and a pressure measuring system. The computing time of the parallel program was reduced by nearly 95% while the simulation result was still quite consistent with experimental data. The GPU parallelization method can successfully solve the problem of low computational efficiency of the 3D sand shooting simulation program, and thus the developed GPU program is appropriate for engineering applications.

Shoot differentiation from protocorm callus cultures of Vanilla planifolia (Orchidaceae: proteomic and metabolic responses at early stage

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Payet Bertrand

2010-05-01

Full Text Available Abstract Background Vanilla planifolia is an important Orchid commercially cultivated for the production of natural vanilla flavour. Vanilla plants are conventionally propagated by stem cuttings and thus causing injury to the mother plants. Regeneration and in vitro mass multiplication are proposed as an alternative to minimize damage to mother plants. Because mass production of V. planifolia through indirect shoot differentiation from callus culture is rare and may be a successful use of in vitro techniques for producing somaclonal variants, we have established a novel protocol for the regeneration of vanilla plants and investigated the initial biochemical and molecular mechanisms that trigger shoot organogenesis from embryogenic/organogenic callus. Results For embryogenic callus induction, seeds obtained from 7-month-old green pods of V. planifolia were inoculated on MS basal medium (BM containing TDZ (0.5 mg l-1. Germination of unorganized mass callus such as protocorm -like structure (PLS arising from each seed has been observed. The primary embryogenic calli have been formed after transferring on BM containing IAA (0.5 mg l-1 and TDZ (0.5 mg l-1. These calli were maintained by subculturing on BM containing IAA (0.5 mg l-1 and TDZ (0.3 mg l-1 during 6 months and formed embryogenic/organogenic calli. Histological analysis showed that shoot organogenesis was induced between 15 and 20 days after embryogenic/organogenic calli were transferred onto MS basal medium with NAA (0.5 mg l-1. By associating proteomics and metabolomics analyses, the biochemical and molecular markers responsible for shoot induction have been studied in 15-day-old calli at the stage where no differentiating part was visible on organogenic calli. Two-dimensional electrophoresis followed by matrix-assisted laser desorption ionization time-of-flight-tandem mass spectrometry (MALDI-TOF-TOF-MS analysis revealed that 15 protein spots are significantly expressed (P Conclusion The

Mesenchymal Stem Cells Enhance Liver Regeneration via Improving Lipid Accumulation and Hippo Signaling

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Yang Liu

2018-01-01

Full Text Available The liver has the potential to regenerate after injury. It is a challenge to improve liver regeneration (LR after liver resection in clinical practice. Bone morrow-derived mesenchymal stem cells (MSCs have shown to have a role in various liver diseases. To explore the effects of MSCs on LR, we established a model of 70% partial hepatectomy (PHx. Results revealed that infusion of MSCs could improve LR through enhancing cell proliferation and cell growth during the first 2 days after PHx, and MSCs could also restore liver synthesis function. Infusion of MSCs also improved liver lipid accumulation partly via mechanistic target of rapamycin (mTOR signaling and enhanced lipid β-oxidation support energy for LR. Rapamycin-induced inhibition of mTOR decreased liver lipid accumulation at 24 h after PHx, leading to impaired LR. And after infusion of MSCs, a proinflammatory environment formed in the liver, evidenced by increased expression of IL-6 and IL-1β, and thus the STAT3 and Hippo-YAP pathways were activated to improve cell proliferation. Our results demonstrated the function of MSCs on LR after PHx and provided new evidence for stem cell therapy of liver diseases.

Strategies to Improve Regeneration of the Soft Palate Muscles After Cleft Palate Repair

Science.gov (United States)

Carvajal Monroy, Paola L.; Grefte, Sander; Kuijpers-Jagtman, Anne Marie; Wagener, Frank A.D.T.G.

2012-01-01

Children with a cleft in the soft palate have difficulties with speech, swallowing, and sucking. These patients are unable to separate the nasal from the oral cavity leading to air loss during speech. Although surgical repair ameliorates soft palate function by joining the clefted muscles of the soft palate, optimal function is often not achieved. The regeneration of muscles in the soft palate after surgery is hampered because of (1) their low intrinsic regenerative capacity, (2) the muscle properties related to clefting, and (3) the development of fibrosis. Adjuvant strategies based on tissue engineering may improve the outcome after surgery by approaching these specific issues. Therefore, this review will discuss myogenesis in the noncleft and cleft palate, the characteristics of soft palate muscles, and the process of muscle regeneration. Finally, novel therapeutic strategies based on tissue engineering to improve soft palate function after surgical repair are presented. PMID:22697475

Biolistic transformation of Carrizo citrange (Citrus sinensis Osb. × Poncirus trifoliata L. Raf.).

Science.gov (United States)

Wu, Hao; Acanda, Yosvanis; Jia, Hongge; Wang, Nian; Zale, Janice

2016-09-01

The development of transgenic citrus plants by the biolistic method. A protocol for the biolistic transformation of epicotyl explants and transgenic shoot regeneration of immature citrange rootstock, cv. Carrizo (Citrus sinensis Osb. × Poncirus trifoliata L. Raf.) and plant regeneration is described. Immature epicotyl explants were bombarded with a vector containing the nptII selectable marker and the gfp reporter. The number of independent, stably transformed tissues/total number of explants, recorded by monitoring GFP fluorescence 4 weeks after bombardment was substantial at 18.4 %, and some fluorescing tissues regenerated into shoots. Fluorescing GFP, putative transgenic shoots were micro-grafted onto immature Carrizo rootstocks in vitro, confirmed by PCR amplification of nptII and gfp coding regions, followed by secondary grafting onto older rootstocks grown in soil. Southern blot analysis indicated that all the fluorescing shoots were transgenic. Multiple and single copies of nptII integrations were confirmed in five regenerated transgenic lines. There is potential to develop a higher throughput biolistics transformation system by optimizing the tissue culture medium to improve shoot regeneration and narrowing the window for plant sampling. This system will be appropriate for transformation with minimal cassettes.

Biotechnology for Improving Food Security in Rwanda

African Journals Online (AJOL)

cntaganda

production of disease-free, high quality planting material and the rapid production of many ... new meristematic centers that are capable of regenerating fully normal plants ... The steps include sterilization and establishment of shoot tip cultures ...

Effect of arbuscular mycorrhizal fungi and multi-combination of bioinoculants on regenerated seedlings of cotton

International Nuclear Information System (INIS)

Pindi, P.K.; Sultana, T.

2014-01-01

Effect of arbuscular mycorrhizal fungi and multi-combination of bioinoculants on regenerated seedlings of cotton Cotton, referred as 'The white gold' is an important commercial crop in India and stands third in the world by means of area of cultivation. Cotton plant regeneration from callus by somatic embryogenesis and its efficiency has been improved significantly in recent times. Our primary investigation was on regenerative studies and multiple shoot induction system focusing mainly on meristematic tissues like seedling cotyledonary nodal explants in RAH-9750 cotton cultivar. An attempt has been made to improve the rate of surveillance and growth of regenerated cotton seedlings by bio-inoculant (mainly AMF) treatment under greenhouse conditions. Out of a total seven pure cultures of AMF fungi, R1-R2 have shown maximum mycorrhizal colonization with RAH-9750 (R) and was identified as Glomus mosseae. This variety was also tested with three different bioinoculants i.e., Rhizobium sp. RHPU-7, Azospirillum sp. PPK-27, Bacillus sp. PU-1, apart from AMF R1-R2 in different combinations. The cotton seedlings have shown the best results in single, dual, triple and multiple combinations i.e R+R1-R2, R+R1-R2+Rhizobium, R+R1-R2+Rhizobium+Azospirillum and R+R1-R2+Rhizobium+Azospirillum+Bacillus respectively. The growth of cotton plants (RAH-9750) generated from meristematic tissue culture was found to be increasing significantly when compared with the normal seeds. Similar results were noticed when the same experiment was subjected to the different soil types of Mahabubnagar district. The investigation clearly infers that better yield of cotton RAH-9750 (R) could be achieved by treating the regenerated cotton seedlings with bioinoculants in different combination in various soil types of Mahabubnagar district. (author)

Characterizing the Suitability of Selected Indigenous Soil Improving Legumes in a Humid Tropical Environment Using Shoot and Root Attributes

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Anikwe, MAN.

2003-01-01

Full Text Available We studied the biomass accumulation, root length, nodulation, and chemical composition of roots and shoot of ten indigenous soil improving legumes in a humid tropical ecosystem with the view to selecting species for soil improvement programmes. Two cultivars of Vigna unguiculata, and one each of Glycine max, Arachis hypogaea, Crotararia ochroleuca, Cajanus cajan, Pueraria phaseoloides, Lablab purpureus, Mucuna pruriens and Vigna subterranea as treatments were planted in 20 kg pots containing soil from an Oxic paleustalf in Nigeria. The pots were arranged in randomized complete block layout with three replications in a greenhouse at IITA Ibadan, Nigeria. Results from the work show that M. pruriens and C. cajan produced the highest quantity of biomass. Root elongation was highest in M. pruriens whereas A. hypogaea produced the most root nodules with native rhizobia. The highest quantity of nodule dry weight was produced by A. hypogaea and P. phaseoloides whereas most of the legumes except G. max and P. phaseoloides had high and statistically comparable N content of between 2.36 and 3.34 mg.kg-1 N. The results show that the legumes have different root and shoot characteristics, which should be taken into consideration when selecting species for soil improvement programmes.

Perfluorodecalin and bone regeneration

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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.

Violence and school shootings.

Science.gov (United States)

Flannery, Daniel J; Modzeleski, William; Kretschmar, Jeff M

2013-01-01

Multiple-homicide school shootings are rare events, but when they happen they significantly impact individuals, the school and the community. We focus on multiple-homicide incidents and identified mental health issues of shooters. To date, studies of school shootings have concluded that no reliable profile of a shooter exists, so risk should be assessed using comprehensive threat assessment protocols. Existing studies primarily utilize retrospective case histories or media accounts. The field requires more empirical and systematic research on all types of school shootings including single victim incidents, those that result in injury but not death and those that are successfully averted. We discuss current policies and practices related to school shootings and the role of mental health professionals in assessing risk and supporting surviving victims.

Adolescent mass shootings: developmental considerations in light of the Sandy Hook shooting.

Science.gov (United States)

Rice, Timothy R; Hoffman, Leon

2015-05-01

Adolescent mass shootings are a special subset of mass killings, which continue despite significant preventative public health efforts. It is often held that these individuals have few salient warning signs that could have been identified. This piece proposes that mass shootings committed by adolescent and post-adolescent young males must be understood from a developmental perspective. The hypothesis proposed in this paper is that such killings occur as the result of the adolescent's frustrated effort to progress along normative development. The goal of normative separation from maternal figures by the boy is presented as a potential risk factor when this goal is thwarted. Childhood case material from the perpetrator of a recent adolescent mass shooting, the Sandy Hook shooting, is discussed as an illustration of this hypothesis. Implications for public health measures and for individualized treatment are presented and developed.

Role of biotechnological interventions in the improvement of castor (Ricinus communis L.) and Jatropha curcas L.

Science.gov (United States)

Sujatha, M; Reddy, T P; Mahasi, M J

2008-01-01

Castor and Jatropha belong to the Euphorbiaceae family. This review highlights the role of biotechnological tools in the genetic improvement of castor and jatropha. Castor is monotypic and breeding programmes have mostly relied on the variability available in the primary gene pool. The major constraints limiting profitable cultivation are: vulnerability to insect pests and diseases, and the press cake is toxic which restrict its use as cattle feed. Conventional breeding techniques have limited scope in improvement of resistance to biotic stresses and in quality improvement owing to low genetic variability for these traits. Genetic diversity was assessed using protein based markers while use of molecular markers is at infancy. In vitro studies in castor have been successful in shoot proliferation from meristematic explants, but not callus-mediated regeneration. Genetic transformation experiments have been initiated for development of insect resistant and ricin-free transgenics with very low transformation frequency. In tropical and subtropical countries jatropha is viewed as a potential biofuel crop. The limitations in available germplasm include; lack of knowledge of the genetic base, poor yields, low genetic diversity and vulnerability to a wide array of insects and diseases. Great scope exists for genetic improvement through conventional methods, induced mutations, interspecific hybridization and genetic transformation. Reliable and highly efficient tissue culture protocols for direct and callus-mediated shoot regeneration and somatic embryogenesis are established for jatropha which indicates potential for widening the genetic base through biotechnological tools. Assessment of genetic diversity using molecular markers disclosed low interaccessional variability in local Jatropha curcas germplasm. The current status and future prospects of in vitro regeneration, genetic transformation and the role of molecular tools in the genetic enhancement of the two

Increased sphingosine-1-phosphate improves muscle regeneration in acutely injured mdx mice

Science.gov (United States)

2013-01-01

beneficial for muscle regeneration and functional gain in dystrophic mice, and that THI, or other pharmacological agents that raise S1P levels systemically, may be developed into an effective treatment for improving muscle function and reducing the pathology of DMD. PMID:23915702

Micropropagation and validation of genetic and biochemical fidelity amongst regenerants of Cassia angustifolia Vahl employing RAPD marker and HPLC.

Science.gov (United States)

Chetri, Siva K; Sardar, Pratima Rani; Agrawal, Veena

2014-10-01

In vitro protocol has been established for clonal propagation of Cassia angustifolia Vahl which is an important source of anticancerous bioactive compounds, sennoside A and B. Nodal explants excised from field raised elite plant (showing optimum level of sennoside A and B) of C. angustifolia when reared on Murashige and Skoog's medium augmented with different cytokinins, viz. N(6)-benzyladenine (BA), N(6)-(2-isopentenyl) adenine (2iP) and 6-furfuryl aminopurine (Kn) differentiated multiple shoots in their axils. Of the three cytokinins, BA at 5 μM proved optimum for differentiating multiple shoots in 95 % cultures with an average of 9.14 shoots per explant within 8 weeks of culture. Nearly, 95 % of the excised in vitro shoots rooted on half strength MS medium supplemented with 10 μM indole-3-butyric acid (IBA). The phenotypically similar micropropagated plants were evaluated for their genetic fidelity employing random amplified polymorphic DNA (RAPD) markers. Eleven individuals, randomly chosen amongst a population of 120 regenerants were compared with the donor plant. A total of 36 scorable bands, ranging in size from 100 to 1,000 bp were generated amongst them by the RAPD primers. All banding profiles from micropropagated plants were monomorphic and similar to those of mother plant proving their true to the type nature. Besides, high performance liquid chromatography evaluation of the sennoside A and B content amongst leaves of the mature regenerants and the elite mother plant too revealed consistency in their content.

In vitro regeneration of solanum aethiopicum L. (scarlet eggplant), an african vegetable crop with potential ornamental value

Science.gov (United States)

Successful in vitro regeneration of plantlets was obtained from shoot tips of five Solanum aethiopicum (African eggplants) accessions evaluated in two media, M1 and M2. The M1 medium consisted of Murashige and Skoog (MS) basal salt mixture supplemented with 20 g/L sucrose, 0.75 g/L MgCl2, and 2 g/L ...

Preculturing effect of thidiazuron on in vitro shoot multiplication and micropropagation round in Capparis decidua (Forsk.) an important multipurpose plant.

Science.gov (United States)

Bukhari, Najat A W; Siddique, Iram; Perveen, Kahkashan

2016-09-01

An efficient protocol was developed for clonal multiplication of an important shrub: Capparis decidua (Forsk.) Edgew, through in vitro shoot induction and multiplication from nodal explants. Pretreatment of nodal explants in a liquid Murashige and Skoog (MS) medium augmented with various thidiazuron (TDZ) concentrations at relatively high levels (5-100 μM) for different time duration (4, 8, 12 and 16 d), proved a significant approach for in vitro shoot production. After an initial exposure time to TDZ, nodal explants were inoculated onto a MS basal medium devoid of TDZ for further induction and proliferation. The highest regeneration rate (85%), average number of shoots/explant (8.7 ± 0.22) and maximum shoot length (3.9 ± 0.33 cm) were obtained from the nodal explants exposed to 50 μM TDZ for 8 d. The nodal explants excised from the proliferated cultures of TDZ (50 μM) for 8 d were used as explants and showed an enhancement rate after next three round of in vitro propagation. Best results for rooting was obtained by ex vitro treatment of shoots with 200 μM indole-3-butyric acid (IBA) for 20 min. as it produced an average of 5.7 ± 0.41 roots per microshoot with 4.4 ± 0.39 cm root length in 84% shoots. Different planting substrates was tested for maximum survival of hardening off micropropagated plantlets and soilrite proved most effective than others as 97.1 ± 7.21 plantlets survived. All micropropagated plants grew well in natural conditions and showed similar morphology to the mother plant.

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

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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.

Current perspectives on shoot branching regulation

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Cunquan YUAN,Lin XI,Yaping KOU,Yu ZHAO,Liangjun ZHAO

2015-03-01

Full Text Available Shoot branching is regulated by the complex interactions among hormones, development, and environmental factors. Recent studies into the regulatory mecha-nisms of shoot branching have focused on strigolactones, which is a new area of investigation in shoot branching regulation. Elucidation of the function of the D53 gene has allowed exploration of detailed mechanisms of action of strigolactones in regulating shoot branching. In addition, the recent discovery that sucrose is key for axillary bud release has challenged the established auxin theory, in which auxin is the principal agent in the control of apical dominance. These developments increase our understan-ding of branching control and indicate that regulation of shoot branching involves a complex network. Here, we first summarize advances in the systematic regulatory network of plant shoot branching based on current information. Then we describe recent developments in the synthesis and signal transduction of strigolactones. Based on these considerations, we further summarize the plant shoot branching regulatory network, including long distance systemic signals and local gene activity mediated by strigolactones following perception of external envi-ronmental signals, such as shading, in order to provide a comprehensive overview of plant shoot branching.

Improvement of Seed Germination and In Vitro Propagation of a Multipurpose Plateau Shrub Species Sophora Moorcroftiana

International Nuclear Information System (INIS)

Fu, Y.; Yao, W.; Li, S.; Li, H.

2016-01-01

Sophora moorcroftiana (Benth.) Baker (Fabaceae) with blue flowers is a shrub species in Qinghai-Tibet Plateau. This species is an important ornamental, ecological and economical species mainly distributed in the wide valleys of Yarlung Tsangpo and Lhasa River. It contains strong drought, solar radiation and sand burial resistance. However, it is on the verge of extinction because of over-exploitation in recent years, seedling production is a bottleneck in this plant's development, and information is lacking on an In vitro propagation system for S. moorcroftiana. Therefore, an effective propagation technique is urgently needed. In the present study, S. moorcroftiana seed germinations both In vitro and on an open moistened filter paper were significantly improved. The best germination percentage (88.67+-0.67) and percentage of cotyledons presented (69.67+-0.33) were obtained when the seeds were placed in moistened filter paper for 30 d after treatment with 98 percent concentration sulphuric acid for 70 min, and then treated with either Gibberellic acid (GA3) 100 mg L/sup-1/ or 500 mg L/sup -1/. Besides, an In vitro propagation system was developed for this species, the impacts of various media combined with different plant growth regulators (PGR) on multiple shoots proliferation were evaluated. The result showed Woody Plant Medium (WPM) supplemented with 1.0 mg L/sup -1/ N/sup 6/ -Benzyladenine (BA) and 0.2 mg L/sup -1/ alpha-Naphthalene acetic acid (NAA) was found to be optimum for production of multiple shoots (89.33 percent shoot regeneration frequency and 18.67 shoots per explant) using cotyledonary node. The best rooted medium for regenerated shoots (89.72 percent, 4.68 roots per shoot) was half-strength Murashige and Skoog (1/2 MS) supplemented with 0.5 mg L/sup -1/ indole-3-butyric acid (IBA) and 0.02 mg L/sup -1/ NAA. The rooted plantlets were successfully acclimated, and survival of plantlets was 75 percent after transfer to soil. These results could be

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

Study on Effect of Type of Explant and Hormone on Callus Induction and Regeneration in Saffron (Crocus sativus L.

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Mohsen Sajjadi

2015-10-01

Full Text Available Saffron (Crocus sativus L. is one of the medicinal plants that contain active components and medicinal materials. Tissue culture of saffron can improve the quality and quantity of the saffron product, increase its export and the farmers’ income. In this study, 36 different types of hormone combinations in the dark and 9 different treatments of hormone combinations in cold (4°C, using different saffron explants (bulb, leaf, scales around leaf and distal parts of the leaf were studied in tissue culture. To investigate the growth of corms, the callus formation and the regeneration rate, three replications for each treatment were used and the length of shoot (cm, the callus formation percentage and the regeneration percentage were measured and statistical analysis was performed. Among the types of explants, only explants from bulbs produced the callus on MS medium containing 2 mg.l-1 BAP and 1 mg.l-1 IBA in both the dark and cold conditions. The highest percentage of regeneration was obtained in MS medium with hormonal composition of 0.3 mg.l-1 TDZ, 1 mg.l-1 BAP, 2 mg.l-1 IBA and 0.01 mg.l-1 GA3 in the cold conditions.

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.

2013-11-22

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene (AVP1) improves the shoot biomass of transgenic barley and increases grain yield in a saline field

KAUST Repository

Schilling, Rhiannon K.; Marschner, Petra; Shavrukov, Yuri N.; Berger, Bettina; Tester, Mark A.; Roy, Stuart John; Plett, Darren Craig

2013-01-01

Cereal varieties with improved salinity tolerance are needed to achieve profitable grain yields in saline soils. The expression of AVP1, an Arabidopsis gene encoding a vacuolar proton pumping pyrophosphatase (H+-PPase), has been shown to improve the salinity tolerance of transgenic plants in greenhouse conditions. However, the potential for this gene to improve the grain yield of cereal crops in a saline field has yet to be evaluated. Recent advances in high-throughput nondestructive phenotyping technologies also offer an opportunity to quantitatively evaluate the growth of transgenic plants under abiotic stress through time. In this study, the growth of transgenic barley expressing AVP1 was evaluated under saline conditions in a pot experiment using nondestructive plant imaging and in a saline field trial. Greenhouse-grown transgenic barley expressing AVP1 produced a larger shoot biomass compared to segregants, as determined by an increase in projected shoot area, when grown in soil with 150 mm NaCl. This increase in shoot biomass of transgenic AVP1 barley occurred from an early growth stage and also in nonsaline conditions. In a saline field, the transgenic barley expressing AVP1 also showed an increase in shoot biomass and, importantly, produced a greater grain yield per plant compared to wild-type plants. Interestingly, the expression of AVP1 did not alter barley leaf sodium concentrations in either greenhouse- or field-grown plants. This study validates our greenhouse-based experiments and indicates that transgenic barley expressing AVP1 is a promising option for increasing cereal crop productivity in saline fields. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.

Silk fibroin enhances peripheral nerve regeneration by improving vascularization within nerve conduits.

Science.gov (United States)

Wang, Chunyang; Jia, Yachao; Yang, Weichao; Zhang, Cheng; Zhang, Kuihua; Chai, Yimin

2018-07-01

Silk fibroin (SF)-based nerve conduits have been widely used to bridge peripheral nerve defects. Our previous study showed that nerve regeneration in a SF-blended poly (l-lactide-co-ɛ-caprolactone) [P(LLA-CL)] nerve conduit is better than that in a P(LLA-CL) conduit. However, the involved mechanisms remain unclarified. Because angiogenesis within a nerve conduit plays an important role in nerve regeneration, vascularization of SF/P(LLA-CL) and P(LLA-CL) conduits was compared both in vitro and in vivo. In the present study, we observed that SF/P(LLA-CL) nanofibers significantly promoted fibroblast proliferation, and vascular endothelial growth factor secreted by fibroblasts seeded in SF/P(LLA-CL) nanofibers was more than seven-fold higher than that in P(LLA-CL) nanofibers. Conditioned medium of fibroblasts in the SF/P(LLA-CL) group stimulated more human umbilical vein endothelial cells (HUVEC) to form capillary-like networks and promoted faster HUVEC migration. The two kinds of nerve conduits were used to bridge 10-mm-length nerve defects in rats. At 3 weeks of reparation, the blood vessel area in the SF/P(LLA-CL) group was significantly larger than that in the P(LLA-CL) group. More regenerated axons and Schwann cells were also observed in the SF/P(LLA-CL) group, which was consistent with the results of blood vessels. Collectively, our data revealed that the SF/P(LLA-CL) nerve conduit enhances peripheral nerve regeneration by improving angiogenesis within the conduit. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2070-2077, 2018. © 2018 Wiley Periodicals, Inc.

Shooting performance is related to forearm temperature and hand tremor size.

Science.gov (United States)

Lakie, M; Villagra, F; Bowman, I; Wilby, R

1995-08-01

The changes in postural tremor of the hand and the subsequent effect on shooting performance produced by moderate cooling and heating of the forearm were studied in six subjects. Cooling produced a large decrease in tremor size of the ipsilateral hand, whereas warming the limb produced an increase in tremor size. Cooling or warming the forearm did not change the peak frequency of tremor significantly, which was quite stable for each subject. The improvement in shooting performance after cooling the forearm, as measured by grouping pattern of the shots, reached statistical significance and warming caused a significant worsening. This measure of performance was shown to correlate (r = 0.776) inversely with tremor size. The causes and implications of these changes are discussed. It is suggested that local cooling may be useful for people who wish temporarily to reduce tremor in order to improve dexterity for shooting and for other purposes.

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.

Shooting mechanisms in nature

NARCIS (Netherlands)

Sakes, Aimée; Wiel, van der Marleen; Henselmans, Paul W.J.; Leeuwen, van Johan L.; Dodou, Dimitra; Breedveld, Paul

2016-01-01

Background In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

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.

New insight into regenerated air heat pump cycle

International Nuclear Information System (INIS)

Zhang, Chun-Lu; Yuan, Han; Cao, Xiang

2015-01-01

Regenerated air (reverse Brayton) cycle has unique potentials in heat pump applications compared to conventional vapor-compression cycles. To better understand the regenerated air heat pump cycle characteristics, a thermodynamic model with new equivalent parameters was developed in this paper. Equivalent temperature ratio and equivalent isentropic efficiency of expander were introduced to represent the effect of regenerator, which made the regenerated air cycle in the same mathematical expressions as the basic air cycle and created an easy way to prove some important features that regenerated air cycle inherits from the basic one. Moreover, we proved in theory that the regenerator does not always improve the air cycle efficiency. Larger temperature ratio and lower effectiveness of regenerator could make the regenerated air cycle even worse than the basic air cycle. Lastly, we found that only under certain conditions the cycle could get remarkable benefits from a well-sized regenerator. These results would enable further study of the regenerated air cycle from a different perspective. - Highlights: • A thermodynamic model for regenerated air heat pump cycle was developed. • Equivalent temperature ratio and equivalent expander efficiency were introduced. • We proved regenerated air cycle can make heating capacity in line with heating load. • We proved the regenerator does not always improve the air cycle efficiency.

Mass shooting and mass media : does media coverage of mass shootings inspire copycat crimes?

OpenAIRE

Mesoudi, A.

2013-01-01

In December 2012, twenty elementary school children and six adult staff members were shot and killed by a single individual at a school in Connecticut. Although this horrific event was met with widespread shock, Americans are sadly all too familiar with such mass shootings. From Columbine in 1999, to Virginia Tech in 2007, to the Colorado cinema shootings earlier in 2012, mass shootings seem to occur with alarming regularity. And although they appear to afflict the United States more than mos...

Improved embryogenic callus induction and plant regeneration in ...

African Journals Online (AJOL)

Pramod Pantha

2016-09-28

Sep 28, 2016 ... solidified with 4.0 g l-1. Gelzan (Phyto Technology Laboratory). Pantha et al. 2167. Callus induction was performed under dark at 28°C (Isotemp. Incubator, Fisher Scientific, Hanover Park, IL, USA). Primary shoots from seed were removed 10 days after inoculation and subculture was done 3 weeks after ...

Effect of antioxidants and associate changes in antioxidant enzymes in controlling browning and necrosis of proliferating shoots of elite Jatropha curcas L

International Nuclear Information System (INIS)

Misra, Pratibha; Toppo, Dibya D.; Gupta, Neha; Chakrabarty, Debasis; Tuli, Rakesh

2010-01-01

A high yielding elite plant of Jatropha curcas was established under aseptic condition from field-grown nodal explants. Shoots were proliferated in MS medium supplemented with 0.5 mg dm -3 benzyladenine and 0.1 mg dm -3 indolebutyric acid along with 10 mg dm -3 adenine sulphate and a combination of 15 mg dm -3 each of L-glutamine and L-arginine. However, within 15-20 d of culture incubation, tissue browning/necrosis leading to poor plant regeneration in vitro was observed. A set of different antioxidants, namely, reduced glutathione, ascorbic acid, tocopherol and cysteine were used in the medium individually and in combination to solve the problem of tissue browning and necrosis. The addition of antioxidants proved beneficial for the growth of the shoots. The optimum medium comprised of 25 mg dm -3 reduced glutathione and 10 mg dm -3 ascorbic acid, where proliferating shoots having highest leaf canopy area, remained fresh, green and regenerative up to 40 d of culture incubation without any subculture. The activities of antioxidant enzymes, such as superoxide dismutase was higher in control shoots, indicating that tissue browning/necrosis was associated with oxidative stress which was further supported by higher contents of H 2 O 2 and phenolics in control shoots compared to the other treatments. Similarly glutathione reductase, ascorbate peroxidase and guiacol peroxidase was higher in treated shoots than control indicating that these shoots have developed antioxidant enzymatic protective system which determine the ability to survive in oxidative stress and up regulation of these enzymes would help to reduce the built up of reactive oxygen species.

Loss of niche-satellite cell interactions in syndecan-3 null mice alters muscle progenitor cell homeostasis improving muscle regeneration.

Science.gov (United States)

Pisconti, Addolorata; Banks, Glen B; Babaeijandaghi, Farshad; Betta, Nicole Dalla; Rossi, Fabio M V; Chamberlain, Jeffrey S; Olwin, Bradley B

2016-01-01

The skeletal muscle stem cell niche provides an environment that maintains quiescent satellite cells, required for skeletal muscle homeostasis and regeneration. Syndecan-3, a transmembrane proteoglycan expressed in satellite cells, supports communication with the niche, providing cell interactions and signals to maintain quiescent satellite cells. Syndecan-3 ablation unexpectedly improves regeneration in repeatedly injured muscle and in dystrophic mice, accompanied by the persistence of sublaminar and interstitial, proliferating myoblasts. Additionally, muscle aging is improved in syndecan-3 null mice. Since syndecan-3 null myofiber-associated satellite cells downregulate Pax7 and migrate away from the niche more readily than wild type cells, syxndecan-3 appears to regulate satellite cell homeostasis and satellite cell homing to the niche. Manipulating syndecan-3 provides a promising target for development of therapies to enhance muscle regeneration in muscular dystrophies and in aged muscle.

In vitro propagation, encapsulation, and genetic fidelity analysis of Terminalia arjuna: a cardioprotective medicinal tree.

Science.gov (United States)

Gupta, Amit K; Harish; Rai, Manoj K; Phulwaria, Mahendra; Agarwal, Tanvi; Shekhawat, N S

2014-07-01

The present study described an improved and reproducible in vitro regeneration system for Terminalia arjuna using nodal segment explants obtained from a mature plant. Shoot tips excised from in vitro proliferated shoots were encapsulated in 3 % sodium alginate and 100 mM CaCl2[Symbol: see text]2H2O for the development of synthetic seeds which may be applicable in short-term storage and germplasm exchange of elite genotype. Shoot multiplication was significantly influenced by a number of factors, namely types and concentrations of plant growth regulators, medium composition, repeated transfer of mother explants, subculturing of in vitro regenerated shoot clumps, agar concentrations, and temperature. Maximum numbers of shoots (16.50 ± 3.67) were observed on modified Murashige and Skoog (MMS) medium containing 0.5 mg l(-1) of benzylaminopurine (BAP) and 0.1 mg l(-1) of naphthalene acetic acid (NAA). To shortening the regeneration pathway, rooting of micropropagated shoots under in vitro condition was excluded and an experiment on ex vitro rooting was conducted and it was observed that the highest percentage of shoots rooted ex vitro when treated with indole-3-butyric acid (IBA, 250 mg l(-1)) + 2-naphthoxy acetic acid (NOA, 250 mg l(-1)) for 5 min. The well-developed ex vitro rooted shoots were acclimatized successfully in soilrite under greenhouse conditions with 80 % survival of plants. Randomly amplified polymorphic DNA (RAPD) analysis confirmed that all the regenerated plants were genetically identical to the mother plant, suggesting the absence of detectable genetic variation in the regenerated plantlets. To the best of our knowledge, this is the first report on synthetic seed production as well as ex vitro rooting and genetic fidelity assessment of micropropagated shoots of T. arjuna.

In vitro Embryogenesis Derived from Shoot Tips in Mass Propagation of Two Selected-Clones of Phalaenopsis

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Budi WINARTO

2016-09-01

Full Text Available Phalaenopsis is of high economic value and market demand in Indonesia; however, orchid products are mostly imported from other countries. ‘Kristina Dwi’ (KD 69.274 and ‘Dedeh’ (D 802.28 are two selected clones with high potential utilized and developed commercially. To support their commercialization, a reliable in vitro propagation protocol is essential.  In the current study, an in vitro mass propagation protocol for KD 69.274 and D 802.28 clones was successfully established using shoot tips as explant sources. A high number of embryos, up to 8.2 embryos per explant, with 58.5% explant regeneration, and 3.5 regenerated-explants in average were regenerated from shoot tips of KD 69.274 clone cultured on  half-strength Murashige and Skoog (MS medium, with full strength micro, Fe-chellate and vitamin containing 0.5 mg/L thidiazuruon (TDZ and 0.25 mg/L N6-benzyladenine (BA. The initial embryos were proliferated by culturing embryos individually on half-strength MS medium with 0.13 mg/L TDZ and 0.25 mg/L BA and resulted in high embryo regeneration up to 91.4%, with 10.2 embryos per explant and no embryo browning. The embryos were multiplied under periodical subcultures of 3 months each, resulting in gradual increasing number of embryos from the first subculture till the fifth subculture, with 23.6 embryos produced, then declined afterward. The embryos were easily germinated on half-strength MS medium with full strength of vitamin and hormone free, with 73.9% embryo germination and 14.9 germinated embryos. Healthy plantlets were stimulated on the same medium with 2 g/L activated charcoal (AC and successfully acclimatized on Cycas rumphii bulk, with 88.3% survival plantlets. Finally, it can be summarized that a new in vitro mass propagation protocol, as new alternative choice for Phalaenopsis propagation, was successfully established.

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.

Administration of multipotent mesenchymal stromal cells restores liver regeneration and improves liver function in obese mice with hepatic steatosis after partial hepatectomy.

Science.gov (United States)

Ezquer, Fernando; Bahamonde, Javiera; Huang, Ya-Lin; Ezquer, Marcelo

2017-01-28

The liver has the remarkable capacity to regenerate in order to compensate for lost or damaged hepatic tissue. However, pre-existing pathological abnormalities, such as hepatic steatosis (HS), inhibits the endogenous regenerative process, becoming an obstacle for liver surgery and living donor transplantation. Recent evidence indicates that multipotent mesenchymal stromal cells (MSCs) administration can improve hepatic function and increase the potential for liver regeneration in patients with liver damage. Since HS is the most common form of chronic hepatic illness, in this study we evaluated the role of MSCs in liver regeneration in an animal model of severe HS with impaired liver regeneration. C57BL/6 mice were fed with a regular diet (normal mice) or with a high-fat diet (obese mice) to induce HS. After 30 weeks of diet exposure, 70% hepatectomy (Hpx) was performed and normal and obese mice were divided into two groups that received 5 × 10 5 MSCs or vehicle via the tail vein immediately after Hpx. We confirmed a significant inhibition of hepatic regeneration when liver steatosis was present, while the hepatic regenerative response was promoted by infusion of MSCs. Specifically, MSC administration improved the hepatocyte proliferative response, PCNA-labeling index, DNA synthesis, liver function, and also reduced the number of apoptotic hepatocytes. These effects may be associated to the paracrine secretion of trophic factors by MSCs and the hepatic upregulation of key cytokines and growth factors relevant for cell proliferation, which ultimately improves the survival rate of the mice. MSCs represent a promising therapeutic strategy to improve liver regeneration in patients with HS as well as for increasing the number of donor organs available for transplantation.

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.

Enzyme-Linked Immunosorbent Assay Testing of Shoots Grown In Vitro and the Use of Immunocapture-Reverse Transcription-Polymerase Chain Reaction Improve the Detection of Prunus necrotic ringspot virus in Rose.

Science.gov (United States)

Moury, B; Cardin, L; Onesto, J P; Candresse, T; Poupet, A

2000-05-01

We developed and evaluated two different methods to improve the detection of the most prevalent virus of rose in Europe, Prunus necrotic ring-spot virus (PNRSV). Immunocapture-reverse transcription-polymerase chain reaction was estimated to be about 100 times more sensitive than double-antibody sandwich-enzyme-linked immunosorbent assay (DAS-ELISA) and showed an equivalent specificity. Based on the observation that PNRSV multiplies actively in young growing tissues (axillary shoots and cuttings), an in vitro culture method allowing rapid (about 15 days) and homogeneous development of dormant axillary buds with high virus titers was standardized. ELISA tests of these young shoots showed, in some cases, a 10(4) to 10(5) increase in sensitivity in comparison to adjacent leaf tissues from the rose mother plants. Between 21 and 98% (depending on the season) more samples were identified as positive by using ELISA on samples from shoot tips grown in vitro rather than on leaves collected directly from the PNRSV-infected mother plants. This simple method of growing shoot tips in vitro improved the confidence in the detection of PNRSV and eliminated problems in sampling appropriate tissues.

Enhanced micropropagation and tiller formation in sugarcane through pretreatment of explants with thidiazuron (TDZ).

Science.gov (United States)

Kumari, Kavita; Lal, Madan; Saxena, Sangeeta

2017-10-01

An efficient, simple and commercially applicable protocol for rapid micropropagation of sugarcane has been designed using variety Co 05011. Pretreatment of shoot tip explants with thidiazuron (TDZ) induced high frequency regeneration of shoot cultures with improved multiplication ratio. The highest frequency (80%) of shoot initiation in explants pretreated with 10 mg/l of TDZ was obtained during the study. Maximum 65% shoot cultures could be established from the explants pretreated with TDZ as compared to minimum 40% establishment in explants without pretreatment. The explants pretreated with 10 mg/l of TDZ required minimum 40 days for the establishment of shoot cultures as compared to untreated explants which required 60 days. The highest average number of shoots per culture (19.1) could be obtained from the explants pretreated with 10 mg/l of TDZ, indicating the highest multiplication ratio (1:6). Highest rooting (over 94%) was obtained in shoots regenerated from pretreated explants on ½ strength MS medium containing 5.0 mg/l of NAA and 50 g/l of sucrose within 15 days. Higher number of tillers/clump (15.3) could be counted in plants regenerated from pretreated explants than untreated ones (10.9 tillers/clump) in field condition, three months after transplantation. Molecular analysis using RAPD and DAMD markers suggested that the pretreatment of explants with TDZ did not adversely affect the genetic stability of regenerated plants and maintained high clonal purity.

The Binomial Distribution in Shooting

Science.gov (United States)

Chalikias, Miltiadis S.

2009-01-01

The binomial distribution is used to predict the winner of the 49th International Shooting Sport Federation World Championship in double trap shooting held in 2006 in Zagreb, Croatia. The outcome of the competition was definitely unexpected.

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

Science.gov (United States)

Rathore, Mangal S; Jha, Bhavanath

2016-03-01

The present investigation aimed to evaluate the degree and pattern of DNA methylation using methylation-sensitive AFLP (MS-AFLP) markers in genetically stable in vitro regenerates of Jatropha curcas L.. The genetically stable in vitro regenerates were raised through direct organogenesis via enhanced axillary shoot bud proliferation (Protocol-1) and in vitro-derived leaf regeneration (Protocol-2). Ten selective combinations of MS-AFLP primers produced 462 and 477 MS-AFLP bands in Protocol-1 (P-1) and Protocol-2 (P-2) regenerates, respectively. In P-1 regenerates, 15.8-31.17 % DNA was found methylated with an average of 25.24 %. In P-2 regenerates, 15.93-32.7 % DNA was found methylated with an average of 24.11 %. Using MS-AFLP in P-1 and P-2 regenerates, 11.52-25.53 % and 13.33-25.47 % polymorphism in methylated DNA was reported, respectively. Compared to the mother plant, P-1 regenerates showed hyper-methylation while P-2 showed hypo-methylation. The results clearly indicated alternation in degree and pattern of DNA methylation; hence, epigenetic instability in the genetically stable in vitro regenerates of J. curcas, developed so far using two different regeneration systems and explants of two different origins. The homologous nucleotide fragments in genomes of P-1 and P-2 regenerates showing methylation re-patterning might be involved in immediate adaptive responses and developmental processes through differential regulation of transcriptome under in vitro conditions.

Effects of NAA and BAP, double-layered media, and light distance on in vitro regeneration of Nelumbo nucifera Gaertn. (lotus), an aquatic edible plant.

Science.gov (United States)

Mahmad, Noraini; Taha, Rosna Mat; Othman, Rashidi; Saleh, Azani; Hasbullah, Nor Azlina; Elias, Hashimah

2014-01-01

In vitro direct regeneration of Nelumbo nucifera Gaertn. was successfully achieved from immature explants (yellow plumule) cultured on a solid MS media supplemented with combinations of 0.5 mg/L BAP and 1.5 mg/L NAA which resulted in 16.00 ± 0.30 number of shoots per explant and exhibited a new characteristic of layered multiple shoots, while normal roots formed on the solid MS basal media. The double-layered media gave the highest number of shoots per explant with a ratio of 2 : 1 (liquid to solid) with a mean number of 16.67 ± 0.23 shoots per explant with the formation of primary and secondary roots from immature explants. In the study involving light distance, the tallest shoot (16.67 ± 0.23 mm) obtained from the immature explants was at a light distance of 200 mm from the source of inflorescent light (1000 lux). The plantlets were successfully acclimatized in clay loam soil after 8 months being maintained under in vitro conditions.

In vitro plant propagation and crop improvement in Lisianthus (Lisianthus Russelianus Hook.

Directory of Open Access Journals (Sweden)

Rodica Pop

2016-11-01

Full Text Available Romania assists at the present time to an increase of production crops for ornamental plants and as a consequence an increased demand of planting material. Thus, improvements of the current multiplication methods are sought after. Lisianthus russelianus Hook. (Eustoma grandiflorum Grise. is a relatively new floral crop to the international market, known for beautiful flowers of various colors and for having a long vase life. This study focused on the development of an efficient protocol for rapid regeneration of this species following known basic and applied aspects of lisianthus biotechnology but exploring new potentials. In the course of experiments conducted, for in vitro multiplication there were used nodal segments (1.5 cm with axillary buds from three F1 hybrids ‘Echo Lavender’, ‘Flamenco White’, ‘Mirage Pastel Pink’ that were inoculated on MS basal medium supplemented with 0.50 mg 1-1 TDZ, 1.0 mg 1-1 BAP and 0.50 mg 1-1 AIA. The results show that the medium with BAP was most effective for obtaining the highest shoots number compared to medium containing TDZ. For rooting induction, two different concentrations of auxin IBA 0.5 mg 1-1 and 1.5 mg 1-1 were used simultaneously on MS basal medium. The highest roots number occurred when using 1.5 mg 1-1 IBA. Both the number of shoots and rooting regeneration were dependent on the cultivar. The highest shoots number was achieved for ’Mirage Pastel Pink’ hybrid (6.91 on the medium containing 1.0 mg 1-1 BAP and 0.50 mg 1-1 IAA.

Development of salt tolerant potato and sugarcane through in vitro techniques

International Nuclear Information System (INIS)

Asad, S.; Iqbal, M.J.; Saif-Ur-Rasheed, M.; Zafar, Y.; Malik, K.A.

1997-01-01

Improvement of sugarcane and potato in Pakistan is hampered by their intricate flowering behavior under natural day-length conditions. The improvement of these crops for their salt tolerance can be carried out by tissue culture mediated techniques. To induce variation in sugarcane, five-week old white yellow nodular embryogenic calli were irradiated with 5, 20, 40 and 60 Gy gamma rays. After one month, the calli were cultured on regeneration media, and plant hardening procedures were optimized. Irradiated and non-irradiated calli were subjected to various levels of salt stress and plant regeneration was investigated. Although growth of sugarcane calli was observed at 200 mM NaCl, regeneration was inhibited even at 50 mM NaCl in the medium. The regenerants from gamma irradiated material are under field evaluation. Variation was detected in both irradiated and salt treated calli by DNA fingerprinting using random amplified polymorphic DNA (RAPD) markers. In potato, 6-7 weeks old in vitro grown plants with single shoots having 8-10 buds were irradiated with 20 Gy gamma rays. Shoot formation was successful only from 50% of the axillary buds. The cultures were subjected to four levels of salinity (50, 100, 150 and 200 mM Nacl). Shoot-tip necrosis was observed along with significant reduction in shoot height. (author). 13 refs, 3 figs, 4 tabs

Development of salt tolerant potato and sugarcane through in vitro techniques

Energy Technology Data Exchange (ETDEWEB)

Asad, S; Iqbal, M J; Saif-Ur-Rasheed, M; Zafar, Y; Malik, K A [Plant Biotechnology Div., National Inst. of Biotechnology and Genetic Engineering, Faisalabad (Pakistan)

1997-07-01

Improvement of sugarcane and potato in Pakistan is hampered by their intricate flowering behavior under natural day-length conditions. The improvement of these crops for their salt tolerance can be carried out by tissue culture mediated techniques. To induce variation in sugarcane, five-week old white yellow nodular embryogenic calli were irradiated with 5, 20, 40 and 60 Gy gamma rays. After one month, the calli were cultured on regeneration media, and plant hardening procedures were optimized. Irradiated and non-irradiated calli were subjected to various levels of salt stress and plant regeneration was investigated. Although growth of sugarcane calli was observed at 200 mM NaCl, regeneration was inhibited even at 50 mM NaCl in the medium. The regenerants from gamma irradiated material are under field evaluation. Variation was detected in both irradiated and salt treated calli by DNA fingerprinting using random amplified polymorphic DNA (RAPD) markers. In potato, 6-7 weeks old in vitro grown plants with single shoots having 8-10 buds were irradiated with 20 Gy gamma rays. Shoot formation was successful only from 50% of the axillary buds. The cultures were subjected to four levels of salinity (50, 100, 150 and 200 mM Nacl). Shoot-tip necrosis was observed along with significant reduction in shoot height. (author). 13 refs, 3 figs, 4 tabs.

Date of shoot collection, genotype, and original shoot position affect early rooting of dormant hardwood cuttings of Populus

Science.gov (United States)

R. S., Jr. Zalesny; A.H. Wiese

2006-01-01

Identifying superior combinations among date of dormant- season shoot collection, genotype, and original shoot position can increase the rooting potential of Populus cuttings. Thus, the objectives of our study were to: 1) evaluate variation among clones in early rooting from hardwood cuttings processed every three weeks from shoots collected...

Optimization of culture conditions (sucrose, pH, and photoperiod) for in vitro regeneration and early detection of somaclonal variation in ginger lime (Citrus assamensis).

Science.gov (United States)

Yaacob, Jamilah Syafawati; Mahmad, Noraini; Mat Taha, Rosna; Mohamed, Normadiha; Mad Yussof, Anis Idayu; Saleh, Azani

2014-01-01

Various explants (stem, leaf, and root) of Citrus assamensis were cultured on MS media supplemented with various combinations and concentrations (0.5-2.0 mg L(-1)) of NAA and BAP. Optimum shoot and root regeneration were obtained from stem cultures supplemented with 1.5 mg L(-1) NAA and 2.0 mg L(-1) BAP, respectively. Explant type affects the success of tissue culture of this species, whereby stem explants were observed to be the most responsive. Addition of 30 gL(-1) sucrose and pH of 5.8 was most optimum for in vitro regeneration of this species. Photoperiod of 16 hours of light and 8 hours of darkness was most optimum for shoot regeneration, but photoperiod of 24 hours of darkness was beneficial for production of callus. The morphology (macro and micro) and anatomy of in vivo and in vitro/ex vitro Citrus assamensis were also observed to elucidate any irregularities (or somaclonal variation) that may arise due to tissue culture protocols. Several minor micromorphological and anatomical differences were observed, possibly due to stress of tissue culture, but in vitro plantlets are expected to revert back to normal phenotype following full adaptation to the natural environment.

ECM Decorated Electrospun Nanofiber for Improving Bone Tissue Regeneration

Directory of Open Access Journals (Sweden)

Yong Fu

2018-03-01

Full Text Available Optimization of nanofiber surface properties can lead to enhanced tissue regeneration outcomes in the context of bone tissue engineering. Herein, we developed a facile strategy to decorate elctrospun nanofibers using extracellular matrix (ECM in order to improve their performance for bone tissue engineering. Electrospun PLLA nanofibers (PLLA NF were seeded with MC3T3-E1 cells and allowed to grow for two weeks in order to harvest a layer of ECM on nanofiber surface. After decellularization, we found that ECM was successfully preserved on nanofiber surface while maintaining the nanostructure of electrospun fibers. ECM decorated on PLLA NF is biologically active, as evidenced by its ability to enhance mouse bone marrow stromal cells (mBMSCs adhesion, support cell proliferation and promote early stage osteogenic differentiation of mBMSCs. Compared to PLLA NF without ECM, mBMSCs grown on ECM/PLLA NF exhibited a healthier morphology, faster proliferation profile, and more robust osteogenic differentiation. Therefore, our study suggests that ECM decoration on electrospun nanofibers could serve as an efficient approach to improving their performance for bone tissue engineering.

The Incorporation of Strontium to Improve Bone-Regeneration Ability of Mesoporous Bioactive Glasses

Directory of Open Access Journals (Sweden)

Sonia Fiorilli

2018-04-01

Full Text Available Over the recent years, mesoporous bioactive glasses (MBGs gained interest as bone regeneration systems, due to their excellent bioactivity and ability to release therapeutic molecules. In order to improve the bone regeneration ability of MBGs, the incorporation of Sr2+ ions, due to its recognized pro-osteogenenic potential, represents a very promising strategy. In this study, MBGs based on the SiO2–CaO system and containing different percentages (2 and 4 mol % of strontium were prepared by two synthesis methods, in the form of microspheres and nanoparticles. Sr-containing MBGs were characterized by FE-SEM, XRD and N2 adsorption/desorption analysis. The in vitro bioactivity in SBF resulted excellent. The assessment of fibroblast cell (line L929 viability showed that Sr-containing MBGs were biocompatible both in form of micro- and nanoparticles. The osteogenic response of osteoblast-like SAOS-2 cells was investigated by analysing the expression of GAPDH, COL1a1, RANKL, SPARC, OPG and ALPL genes, as cell differentiation markers. The results indicate that the incorporation of Sr into MBG is beneficial for bone regeneration as promotes a pro-osteogenic effect, paving the way to the design of advanced devices enabled by these nanocarriers also in combination with drug release, for the treatment of bone pathologies, particularly in patients with osteoporosis.

From gene manipulation to forest establishment: shoot cultures of woody plants can be a central tool

Energy Technology Data Exchange (ETDEWEB)

McCown, B.H.

1985-05-01

Establishing germplasm of woody plants in microculture as shoot cultures has proved to be an effective method of overcoming many of the obstacles in working with these crops. Shoot cultures eliminate the changes associated with seasonal growth cycles and phase change and put large plants into a more manageable form. Well-established shoot cultures are central to successful clonal propagation systems for forest trees as well as to genetic improvement based on the use of cellular techniques such as protoplast manipulation. The physiological basis as to why tissues from shoot cultures are so readily manipulated is not well understood.

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

Improved methods in Agrobacterium-mediated transformation of almond using positive (mannose/pmi) or negative (kanamycin resistance) selection-based protocols.

Science.gov (United States)

Ramesh, Sunita A; Kaiser, Brent N; Franks, Tricia; Collins, Graham; Sedgley, Margaret

2006-08-01

A protocol for Agrobacterium-mediated transformation with either kanamycin or mannose selection was developed for leaf explants of the cultivar Prunus dulcis cv. Ne Plus Ultra. Regenerating shoots were selected on medium containing 15 muM kanamycin (negative selection), while in the positive selection strategy, shoots were selected on 2.5 g/l mannose supplemented with 15 g/l sucrose. Transformation efficiencies based on PCR analysis of individual putative transformed shoots from independent lines relative to the initial numbers of leaf explants tested were 5.6% for kanamycin/nptII and 6.8% for mannose/pmi selection, respectively. Southern blot analysis on six randomly chosen PCR-positive shoots confirmed the presence of the nptII transgene in each, and five randomly chosen lines identified to contain the pmi transgene by PCR showed positive hybridisation to a pmi DNA probe. The positive (mannose/pmi) and the negative (kanamycin) selection protocols used in this study have greatly improved transformation efficiency in almond, which were confirmed with PCR and Southern blot. This study also demonstrates that in almond the mannose/pmi selection protocol is appropriate and can result in higher transformation efficiencies over that of kanamycin/nptII selection protocols.

Training visual control in wheelchair basketball shooting

NARCIS (Netherlands)

Oudejans, R.R.D.; Heubers, S.; Ruitenbeek, J-R.J.A.C.; Janssen, T.W.J.

2012-01-01

We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use

Improved axonal regeneration of transected spinal cord mediated by multichannel collagen conduits functionalized with neurotrophin-3 gene.

Science.gov (United States)

Yao, L; Daly, W; Newland, B; Yao, S; Wang, W; Chen, B K K; Madigan, N; Windebank, A; Pandit, A

2013-12-01

Functionalized biomaterial scaffolds targeted at improving axonal regeneration by enhancing guided axonal growth provide a promising approach for the repair of spinal cord injury. Collagen neural conduits provide structural guidance for neural tissue regeneration, and in this study it is shown that these conduits can also act as a reservoir for sustained gene delivery. Either a G-luciferase marker gene or a neurotrophin-3-encoding gene, complexed to a non-viral, cyclized, PEGylated transfection vector, was loaded within a multichannel collagen conduit. The complexed genes were then released in a controlled fashion using a dual release system both in vitro and in vivo. For evaluation of their biological performance, the loaded conduits were implanted into the completely transected rat thoracic spinal cord (T8-T10). Aligned axon regeneration through the channels of conduits was observed one month post-surgery. The conduits delivering neurotrophin-3 polyplexes resulted in significantly increased neurotrophin-3 levels in the surrounding tissue and a statistically higher number of regenerated axons versus the control conduits (P<0.05). This study suggests that collagen neural conduits delivering a highly effective non-viral therapeutic gene may hold promise for repair of the injured spinal cord.

Exploring the efficiency potential for an active magnetic regenerator

DEFF Research Database (Denmark)

Eriksen, Dan; Engelbrecht, Kurt; Haffenden Bahl, Christian Robert

2016-01-01

A novel rotary state of the art active magnetic regenerator refrigeration prototype was used in an experimental investigation with special focus on efficiency. Based on an applied cooling load, measured shaft power, and pumping power applied to the active magnetic regenerator, a maximum second-la...... and replacing the packed spheres with a theoretical parallel plate regenerator. Furthermore, significant potential efficiency improvements through optimized regenerator geometries are estimated and discussed......., especially for the pressure drop, significant improvements can be made to the machine. However, a large part of the losses may be attributed to regenerator irreversibilities. Considering these unchanged, an estimated upper limit to the second-law efficiency of 30% is given by eliminating parasitic losses...

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

Rampage shootings: an historical, empirical, and theoretical overview.

Science.gov (United States)

Rocque, Michael; Duwe, Grant

2018-02-01

Rampage shootings is a relatively new term to describe a phenomenon that has a long history. Rampage shootings are mass shootings (generally defined as involving four or more victims), taking place in a public location, with victims chosen randomly or for symbolic purposes. These shootings are isolated events, meaning they are not connected to another criminal act (such as robbery or terrorism). Research suggests that rampage shootings are not a new phenomenon, but have occurred throughout the US since the early 1900s. There is some evidence of an increase in recent years, but definitional differences across studies and data sources make interpreting trends somewhat tenuous. Theories regarding the perpetration of rampage shootings center on masculinity, mental illness, and contagion effects. Policies aimed at preventing rampage shootings remain somewhat controversial and not well-tested in the literature. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modeling shoot-tip temperature in the greenhouse environment

International Nuclear Information System (INIS)

Faust, J.E.; Heins, R.D.

1998-01-01

An energy-balance model is described that predicts vinca (Catharanthus roseus L.) shoot-tip temperature using four environmental measurements: solar radiation and dry bulb, wet bulb, and glazing material temperature. The time and magnitude of the differences between shoot-tip and air temperature were determined in greenhouses maintained at air temperatures of 15, 20, 25, 30, or 35 °C. At night, shoot-tip temperature was always below air temperature. Shoot-tip temperature decreased from 0.5 to 5 °C below air temperature as greenhouse glass temperature decreased from 2 to 15 °C below air temperature. During the photoperiod under low vapor-pressure deficit (VPD) and low air temperature, shoot-tip temperature increased ≈4 °C as solar radiation increased from 0 to 600 W·m -2 . Under high VPD and high air temperature, shoot-tip temperature initially decreased 1 to 2 °C at sunrise, then increased later in the morning as solar radiation increased. The model predicted shoot-tip temperatures within ±1 °C of 81% of the observed 1-hour average shoot-tip temperatures. The model was used to simulate shoot-tip temperatures under different VPD, solar radiation, and air temperatures. Since the rate of leaf and flower development are influenced by the temperature of the meristematic tissues, a model of shoot-tip temperature will be a valuable tool to predict plant development in greenhouses and to control the greenhouse environment based on a plant temperature setpoint. (author)

The study of ascorbate peroxidase, catalase and peroxidase during in vitro regeneration of Argyrolobium roseum.

Science.gov (United States)

Habib, Darima; Chaudhary, Muhammad Fayyaz; Zia, Muhammad

2014-01-01

Here, we demonstrate the micropropagation protocol of Argyrolobium roseum (Camb.), an endangered herb exhibiting anti-diabetic and immune-suppressant properties, and antioxidant enzymes pattern is evaluated. Maximum callogenic response (60 %) was observed from leaf explant at 1.0 mg L(-1) 1-nephthalene acetic acid (NAA) and 0.5 mg L(-1) 6-benzyl aminopurine (BA) in Murashige and Skoog (MS) medium using hypocotyl and root explants (48 % each). Addition of AgNO3 and PVP in the culture medium led to an increase in callogenic response up to 86 % from leaf explant and 72 % from hypocotyl and root explants. The best shooting response was observed in the presence of NAA, while maximum shoot length and number of shoots were achieved based on BA-supplemented MS medium. The regenerated shoots were rooted and successfully acclimatized under greenhouse conditions. Catalase and peroxidase enzymes showed ascending pattern during in vitro plant development from seed while ascorbate peroxidase showed descending pattern. Totally reverse response of these enzymes was observed during callus induction from three different explants. During shoot induction, catalase and peroxidase increased at high rate while there was a mild reduction in ascorbate peroxidase activity. Catalase and peroxidase continuously increased; on the other hand, ascorbate peroxidase activity decreased during root development and acclimatization states. The protocol described here can be employed for the mass propagation and genetic transformation of this rare herb. This study also highlights the importance and role of ascorbate peroxidase, catalase, and peroxidase in the establishment of A. roseum in vitro culture through callogenesis and organogenesis.

Aberrant regeneration of the third cranial nerve.

Science.gov (United States)

Shrestha, U D; Adhikari, S

2012-01-01

Aberrant regeneration of the third cranial nerve is most commonly due to its damage by trauma. A ten-month old child presented with the history of a fall from a four-storey building. She developed traumatic third nerve palsy and eventually the clinical features of aberrant regeneration of the third cranial nerve. The adduction of the eye improved over time. She was advised for patching for the strabismic amblyopia as well. Traumatic third nerve palsy may result in aberrant regeneration of the third cranial nerve. In younger patients, motility of the eye in different gazes may improve over time. © NEPjOPH.

Simulating the partitioning of biomass and nitrogen between roots and shoot in crop and grass plants

NARCIS (Netherlands)

Yin, X.; Schapendonk, A.H.C.M.

2004-01-01

Quantification of the assimilate partitioning between roots and shoot has been one of the components that need improvement in crop growth models. In this study we derived two equations for root-shoot partitioning of biomass and nitrogen (N) that hold for crops grown under steady-state conditions.

Combination of the auxins NAA, IBA, and IAA with GA3 improves the commercial seed-tuber production of potato (Solanum tuberosum L.) under in vitro conditions.

Science.gov (United States)

Kumlay, Ahmet Metin

2014-01-01

The study compared the effects of 1.0 × MS medium containing various concentrations of α-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA), alone or in combination with gibberellic acid (GA3) in micropropagation of three potato (Solanum tuberosum L.) cultivars Pasinler, Granola, and Caspar using binodal stem cuttings. The results testified improved regeneration on 1.0 × MS medium containing variants of NAA, IAA, and IBA plus GA3 on all cultivars. The minimum days to shoot induction on three cultivars ranged 4.25-5 d on 1.0 × MS medium containing 0.25 mg L(-1) GA3 + 1 mg L(-1) NAA. The longest shoots (11.8 cm), maximum number of nodes (13.50), and maximum number of leaves (11.00) were recorded on cv. Caspar on 1.0 × MS medium containing 1 mg L(-1) NAA + 0.25 mg L(-1) GA3. The minimum time to root induction (12.25 d) was noted on cv. Pasinler on the same medium. All of the regenerated shoots could be easily rooted. The results showed that the combined effect of various concentrations of NAA, IAA, and IBA plus GA3 was more pronounced compared to the auxins used alone. The results of this research are of significant importance for potato breeders.

Training Visual Control in Wheelchair Basketball Shooting

Science.gov (United States)

Oudejans, Raoul R. D.; Heubers, Sjoerd; Ruitenbeek, Jean-Rene J. A. C.; Janssen, Thomas W. J.

2012-01-01

We examined the effects of visual control training on expert wheelchair basketball shooting, a skill more difficult than in regular basketball, as players shoot from a seated position to the same rim height. The training consisted of shooting with a visual constraint that forced participants to use target information as late as possible.…

Radiosensitivity of in vitro Cultured Banana Shoot-Tips

International Nuclear Information System (INIS)

Elagamawy, M.R.

2002-01-01

Longitudinally dissected shoot apices of Grand Nain, Williams and Maghrabi banana cultivars were exposed to gamma irradiation with Cobalt 60 source at the doses of 0, 20, 40 and 60 Gy and immediately placed into proliferation medium. A number of micropropagation cycles after irradiation were necessary up to M1 V2 to M1 V4 stage to let mutated sectors developing into non-chimeric shoots. Radiosensitivity was evaluated by the rate of shoot proliferation and by the shoot fresh weight increase. Increasing gamma doses caused reduction in survival rates and average number of shoots. Grand Nain exhibited the highest multiplication- rate (3.1). The lower dose (20 Gy) enhanced shoot multiplication ratio specially in Williams and Maghrabi, which however decreased with increased doses. The doses of 20-40 Gy yielded Ld50, with sensible degree of shoot multiplication, which occurred hardly ever beyond 40 Gy. The dose of 60 Gy resulted 80% lethal shoot growth. Linear decrease in fresh weight was observed in post-irradiation recovery, notably in the Maghrabi. In contradictory vulnerable damage was observed in Williams which showed the highest fresh weight value. Shoot proliferation appeared generally on the surface of the corm. Root formation was observed without additional hormone. The roots were dark colored and was decreased with the increased of dosage

Carbon dioxide exchange in Norway spruce at the shoot, tree and ecosystem scale.

Science.gov (United States)

Wallin, G; Linder, S; Lindroth, A; Räntfors, M; Flemberg, S; Grelle, A

2001-08-01

Net CO2 exchange in a 35-year-old boreal Norway spruce (Picea abies (L.) Karst.) forest in northern Sweden was measured at the shoot (NSE), tree (NTE) and ecosystem levels (NEE) by means of shoot cuvettes, whole-tree chambers and the eddy covariance technique, respectively. We compared the dynamics of gross primary production (GPP) at the three levels during the course of a single week. The diurnal dynamics of GPP at each level were estimated by subtracting half-hourly or hourly model-estimated values of total respiration (excluding light-dependent respiration) from net CO(2) exchange. The relationship between temperature and total respiration at each level was derived from nighttime measurements of NSE, NTE and NEE over the course of 1 month. There was a strong linear relationship (r2 = 0.93) between the hourly estimates of GPP at the shoot and tree levels, but the correlation between shoot- and ecosystem-level GPP was weaker (r2 = 0.69). However, the correlation between shoot- and ecosystem-level GPP was improved (r2 = 0.88) if eddy covariance measurements were restricted to periods when friction velocity was > or = 0.5 m s(-1). Daily means were less dependent on friction velocity, giving an r2 value of 0.94 between shoot- and ecosystem-level GPP. The correlation between shoot and tree levels also increased when daily means were compared (r2 = 0.98). Most of the measured variation in carbon exchange rate among the shoot, tree and ecosystem levels was the result of periodic low coupling between vegetation and the atmosphere at the ecosystem level. The results validate the use of measurements at the shoot and tree level for analyzing the contribution of different compartments to net ecosystem CO2 exchange.

De novo regeneration of Scrophularia yoshimurae Yamazaki (Scrophulariaceae) and quantitative analysis of harpagoside, an iridoid glucoside, formed in aerial and underground parts of in vitro propagated and wild plants by HPLC.

Science.gov (United States)

Sagare, A P; Kuo, C L; Chueh, F S; Tsay, H S

2001-11-01

A protocol for de novo regeneration and rapid micropropagation of Scrophularia yoshimurae (Scrophulariaceae) has been developed. Multiple shoot development was achieved by culturing the shoot-tip, leaf-base, stem-node and stem-internode explants on Murashige and Skoog (MS) medium supplemented with 4.44 microM N6-benzyladenine (BA) and 1.07 microM alpha-naphthaleneacetic acid (NAA). Stem-node and shoot-tip explants showed the highest response (100%) followed by stem-internode (74.4%) and leaf-base (7.7%) explants. The shoots were multiplied by subculturing on the same medium used for shoot induction. Shoots were rooted on growth regulator-free MS basal medium and the plantlets were transplanted to soil and acclimatized in the growth chamber. The content of harpagoside, a quantitatively predominant iridoid glycoside, in different plant material was determined by high performance liquid chromatography (HPLC). The analysis revealed that the content of harpagoside in the aerial and underground parts of S. yoshimurae was significantly higher than the marketed crude drug (underground parts of Scrophularia ningpoensis).

A School Shooting Plot Foiled

Science.gov (United States)

Swezey, James A.; Thorp, Kimberly A.

2010-01-01

Dinkes, Cataldi, and Lin-Kelly (2007) claims that 78% of public schools reported one or more violent incidents during the 2005/2006 school year. School shootings are a rare but real threat on school campuses. Shootings at private schools are even less frequent with only a few recorded examples in the United States. This case study examines how a…

Mass Shootings, Mental Illness, and Gun Control.

Science.gov (United States)

Philpott-Jones, Sean

2018-03-01

In the wake of the Stoneman Douglas School shooting, Republican and Democratic leaders-like the American electorate they represent-remain sharply divided in their responses to gun violence. They are united in their condemnation of these mass shootings, but they disagree about whether stricter or looser gun control laws are the answer. Those on the right side of the political aisle suggest that the issue is one of mental illness rather than gun control. Conversely, those who are more liberal or progressive in their political learnings are quick to condemn attempts to reframe the issue of mass shootings as a mental health problem. Both sides are wrong. Mass shootings are indeed partially a mental health problem, albeit one poorly addressed by our current laws and policies. But the solution to mass shootings also needs to consider strategies that may reduce gun violence in general. © 2018 The Hastings Center.

Enhancement of alkylation catalysts for improved supercritical fluid regeneration

Science.gov (United States)

Ginosar, Daniel M.; Petkovic, Lucia M.

2010-12-28

A method of modifying an alkylation catalyst to reduce the formation of condensed hydrocarbon species thereon. The method comprises providing an alkylation catalyst comprising a plurality of active sites. The plurality of active sites on the alkylation catalyst may include a plurality of weakly acidic active sites, intermediate acidity active sites, and strongly acidic active sites. A base is adsorbed to a portion of the plurality of active sites, such as the strongly acidic active sites, selectively poisoning the strongly acidic active sites. A method of modifying the alkylation catalyst by providing an alkylation catalyst comprising a pore size distribution that sterically constrains formation of the condensed hydrocarbon species on the alkylation catalyst or by synthesizing the alkylation catalyst to comprise a decreased number of strongly acidic active sites is also disclosed, as is a method of improving a regeneration efficiency of the alkylation catalyst.

SHOOT2.0: An indirect grid shooting package for optimal control problems, with switching handling and embedded continuation

OpenAIRE

Martinon , Pierre; Gergaud , Joseph

2010-01-01

The SHOOT2.0 package implements an indirect shooting method for optimal control problems. It is specifically designed to handle control discontinuities, with an automatic switching detection that requires no assumptions concerning the number of switchings. Special care is also devoted to the computation of the Jacobian matrix of the shooting function, using the variational system instead of classical finite differences. The package also features an embedded continuation method and an automati...

Morphogenesis and tissue culture of sweet orange (Citrus sinensis (L.) Osb.): effect of temperature and photosynthetic radiation

International Nuclear Information System (INIS)

Duran-Vila, N.; Gogorcena, Y.; Ortega, V.; Ortiz, J.; Navarro, L.

1992-01-01

Both incubation temperature and photosynthetic radiation affected morphogenesis, callus culture and plantlet culture of sweet orange (Citrus sinensis) cultured in vitro. Bud culture from nodal stem segments, regeneration of shoots and buds from internode stem segments and induction of primary callus were near optimal at incubation temperatures between 21–30°C. The optimal temperature for root formation was 27°C with temperatures above and below being clearly deleterious. Incubation in the dark or under low photosynthetic photon flux density (PPFD) was beneficial for callus induction and growth and also favored the production of rooted plantlets from bud cultures. Incubation in the dark improved considerably the regeneration of shoots and buds from internode segments and the recovery of whole plants. No off-types, as determined by protein and isoenzyme analysis, were observed among plantlets recovered from bud cultures or from regeneration of shoots from internode stem segments

Arabidopsis CDS blastp result: AK241762 [KOME

Lifescience Database Archive (English)

Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 9e-17 ...

Arabidopsis CDS blastp result: AK242393 [KOME

Lifescience Database Archive (English)

Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 3e-13 ...

Arabidopsis CDS blastp result: AK242986 [KOME

Lifescience Database Archive (English)

Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-13 ...

Arabidopsis CDS blastp result: AK241281 [KOME

Lifescience Database Archive (English)

Full Text Available ctor, putative / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum a...nd contains PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-12 ...

Shooting responses of potato ( Solanum tuberosum L.) varieties in ...

African Journals Online (AJOL)

A study was conducted in 2012 and 2013 at IRAD Bambui (Cameroon) to evaluate the rate of shooting in four improved IRAD potato varieties: Cipira, Tubira, Mafo and Bambui wonder. Liquid and solid media stocks prepared according to the International Potato Center (CIP)'s protocol were used. A randomized complete ...

In vitro regeneration of cocona (Solanum sessiliflorum, Solanaceae) cultivars for commercial production.

Science.gov (United States)

Schuelter, A R; Grunvald, A K; Amaral, A T; da Luz, C L; Luz, C L; Gonçalves, L M; Stefanello, S; Scapim, C A

2009-08-11

Cocona (Solanum sessiliflorum Dunal) is a solanaceous shrub native to the Amazon region that produces an edible fruit. This species has numerous advantages, particularly a high nutritional value and productivity. However, due to irregular germination and rapid loss of seed viability, there are few plantations for production on a large scale. Development of alternative propagation strategies is essential for the production of homogeneous seedlings of genotypes with superior agronomic performance. We developed techniques for in vitro regeneration of the cocona varieties Santa Luzia and Thaís for large-scale production of healthy plantlets. Twenty days after seeding, seedling segments germinated in vitro were used as explant sources. Three successive experiments were performed: one to test the effect of the explant source and combinations of two growth regulators, auxin (indole acetic acid, IAA) and kinetin (KIN), on the morphogenetic response; another to investigate the effect of the combination of growth regulators on the morphogenetic response of hypocotyl segments, and another to evaluate how sucrose concentration affects the development of adventitious shoots. The best shoot induction was obtained using hypocotyl segments and stem apices, while rhizogenesis was greatest in leaves with a petiole. The number of adventitious shoots per explant on hypocotyl segments increased with 10 and 20 mg/L KIN, combined with 0.02 mg/L IAA in the variety Santa Luzia. Sucrose combined with these growth regulator levels increased the average number of calli; these were optimally produced when 45 g/L sucrose and 0.01 mg/L IAA + 20 mg/L KIN were applied. Only sucrose concentration influenced shoot proliferation in the two S. sessiliflorum varieties, with a maximum at 17.5 g/L.

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

Science.gov (United States)

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

2014-11-01

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

[School shooting in statu nascendi].

Science.gov (United States)

Knecht, Thomas

2012-01-01

In the last few years, amok-like killings and especially so-called "school shootings" have received a great deal of public attention both in the Old and the New world. Meanwhile, criminal psychological research has gained a thorough insight into this dangerous development in young people. Thus, the possibility to assess the concrete threat of such a multiple killing before it is carried out has been considerably improved, as many prognostic criteria have been worked out in the meantime. The case report presented shows that it is possible to exercise a favourable influence on this critical negative trend.

School shootings: law enforcement and school district networking

OpenAIRE

Topadzhikyan, Tigran

2013-01-01

CHDS State/Local School shootings have happened in the past and will happen again. The history of school shootings prompts all stakeholders to look at ways to prevent them from happening, and if they do happen, to be resilient. Change is needed in the prevention of school shootings. The case studies of Virginia Tech, Sandy Hook, E. O. Green Junior High, and Beslan school shootings reveal that the lack of information sharing and lack of communication were flaws; and the incidents might have...

Phytosterols elevation in bamboo shoot residue through laboratorial scale solid-state fermentation using isolated Aspergillus niger CTBU.

Science.gov (United States)

Zheng, X X; Chen, R S; Shen, Y; Yin, Z Y

2014-04-01

Aspergillus niger CTBU isolated from local decayed bamboo shoot residue was employed to solid-state fermentation (SSF) of bamboo shoot residue to elevate the content of phytosterols. Strain acclimatization was carried out under the fermentation condition using bamboo shoot as substrate for fermentation performance improvement. The optimal fermentation temperature and nitrogen level were investigated using acclimatized strain, and SSF was carried out in a 500-ml Erlenmeyer flask feeding 300-mg bamboo shoot residue chips under the optimal condition (33 °C and feeding 4 % urea), and 1,186 mg (100 g)(-1) of total phytosterol was attained after 5-day fermentation, in comparison, only 523 mg (100 g)(-1) of phytosterol was assayed in fresh shoots residue. HPLC analysis of the main composition of total phytosterols displays that the types of phytosterols and composition ratio of main sterols keep steady. This laboratorial scale SSF unit could be scaled up for raw phytosterols production from discarded bamboo shoot residue and could reduce its cost.

Adenovirus-mediated transfer of hepatocyte growth factor gene to human dental pulp stem cells under good manufacturing practice improves their potential for periodontal regeneration in swine.

Science.gov (United States)

Cao, Yu; Liu, Zhenhai; Xie, Yilin; Hu, Jingchao; Wang, Hua; Fan, Zhipeng; Zhang, Chunmei; Wang, Jingsong; Wu, Chu-Tse; Wang, Songlin

2015-12-15

Periodontitis is one of the most widespread infectious diseases in humans. We previously promoted significant periodontal tissue regeneration in swine models with the transplantation of autologous periodontal ligament stem cells (PDLSCs) and PDLSC sheet. We also promoted periodontal tissue regeneration in a rat model with a local injection of allogeneic bone marrow mesenchymal stem cells. The purpose of the present study is to investigate the roles of the hepatocyte growth factor (HGF) and human dental pulp stem cells (DPSCs) in periodontal tissue regeneration in swine. In the present study, we transferred an adenovirus that carried HGF gene into human DPSCs (HGF-hDPSCs) under good manufacturing practice (GMP) conditions. These cells were then transplanted into a swine model for periodontal regeneration. Twenty miniature pigs were used to generate periodontitis with bone defect of 5 mm in width, 7 mm in length, and 3 mm in depth. After 12 weeks, clinical, radiological, quantitative and histological assessment of regenerated periodontal tissues was performed to compare periodontal regeneration in swine treated with cell implantation. Our study showed that injecting HGF-hDPSCs into this large animal model could significantly improve periodontal bone regeneration and soft tissue healing. A hDPSC or HGF-hDPSC sheet showed superior periodontal tissue regeneration compared to the injection of dissociated cells. However, the sheets required surgical placement; thus, they were suitable for surgically-managed periodontitis treatments. The adenovirus-mediated transfer of the HGF gene markedly decreased hDPSC apoptosis in a hypoxic environment or in serum-free medium, and it increased blood vessel regeneration. This study indicated that HGF-hDPSCs produced under GMP conditions significantly improved periodontal bone regeneration in swine; thus, this method represents a potential clinical application for periodontal regeneration.

Regeneration and health: a structured, rapid literature review.

Science.gov (United States)

McCartney, G; Hearty, W; Taulbut, M; Mitchell, R; Dryden, R; Collins, C

2017-07-01

To identify and synthesise what is known about the impacts of regeneration on health, health inequalities and their socio-economic determinants. Rapid, structured literature review. A rapid, structured approach was undertaken to identifying relevant studies involving a search of peer-reviewed literature databases, an Internet search to identify relevant grey literature, and a review of articles citing two key systematic reviews. The identified citations were screened, critically appraised according to the research design and narratively synthesised. Of the 1382 identified citations, 46 were screened as relevant to the review and included in the synthesis. Fifteen citations were reviews but most of the evidence identified or included within the reviews was of medium or low quality due to a lack of longitudinal follow-up, low response rates or attrition. The evidence base on the impacts of regeneration is generally not of high quality and is prone to bias. However, it is theorised as being an important means of addressing the socio-economic determinants of health. Housing refurbishment (generally, and for specific improvements) seems likely to lead to small improvements in health, whereas rehousing and mixed-tenure approaches have less clear impacts on health and carry risks of disruption to social networks and higher rents. Changes in the social composition of communities (gentrification) is a common outcome of regeneration and some 'partnership' approaches to regeneration have been shown to have caused difficulties within communities. The evidence base for regeneration activities is limited but they have substantial potential to contribute to improving population health. Better quality evidence is available for there being positive health impacts from housing-led regeneration programmes involving refurbishment and specific housing improvements. There is also some evidence of the potential harms of regeneration activities, including social stratification

Some factors affecting the in vitro culture of banana

International Nuclear Information System (INIS)

Zadi, T.A.N.; Khan, N.H.; Rehman, Z.U.

2006-01-01

Factors affecting in vitro regeneration of shoots in shoot tip explant cultures of banana cultivar 'Basrai', such as solid and liquid media, growth regulators, vitamins, and antioxidants were studied. Three-quarters strength of MS liquid medium supplemented with 17.75 micro m 6-benzyladenine (BA), 11.42 micro M indole-3-acetic acid (IAA) and 205 micro M adenine sulphate induced the formation of mean number of 12.3 shoots, with the mean length of 3.0 cm, after three weeks of culture. Maximum shoot multiplication (14.33) occurred in liquid medium containing 22.19 micro M BA. Addition of 2.0% activated charcoal (AC) to the liquid medium improved quality of the regenerated plants with expanded and glossy leaves, though the number of shoots was reduced (13.66). Profuse formation of roots was characteristically induced by AC. Addition of citric acid (CA) to the medium caused decline in morphogenetic expression of the cultures. (author)

Exogenous Catalase and Pyruvate Dehydrogenase Improve Survival and Regeneration and Affect Oxidative Stress in Cryopreserved Dendrobium nobile Protocorm-like Bodies.

Science.gov (United States)

Di, W; Jia, M X; Xu, J; Li, B L; Liu, Y

Reactive oxygen species (ROS)-induced oxidative damage is responsible for viability loss in plant tissues following cryopreservation. Antioxidants may improve viability by preventing or repairing the injury. This work aimed at studying the effect of catalase (CAT) and pyruvate dehydrogenase (PDH), which are involved in ROS metabolism and are differentially expressed during pollen cryopreservation, for cryopreservation of Dendrobium nobile Lindl. 'Hamana Lake Dream' protocorm-like bodies (PLBs). Different concentrations of exogenous CAT or PDH were added at the loading, PVS2 treatment, unloading steps during vitrification-cryopreservation of PLBs. Their survival and regeneration were evaluated and correlated with physiological oxidative indexes. PLB survival increased significantly when CAT and PDH were added separately to the unloading solution at a suitable concentration. CAT at 400 U·ml -1 increased PLB survival and regeneration by 33.5 and 14.6 percent respectively. It had no impact on the production of superoxide anion radical (·O2-) and on superoxide dismutase (SOD) activity, but it reduced the hydrogen peroxide (H 2 O 2 ) and malondialdehyde (MDA) contents and enhanced ascorbic acid (AsA) and endogenous CAT levels compared to PLBs cryopreserved using the standard vitrification protocol (CK1). PDH at 0.1 U·ml -1 significantly improved PLB survival (by 2.5 percent), but it had no marked effect on regeneration compared to the CK1 group. It induced the same variations in ·O2-, AsA and endogenous CAT levels that were observed following CAT addition. However, PDH did not affect the H 2 O 2 and MDA content but significantly increased SOD activity. These results indicate that the addition of 400 U·ml -1 CAT and 0.1 U·ml -1 PDH at the unloading step increased survival of cryopreserved PLBs and that this improvement was associated with scavenging of H 2 O 2 and the repair of oxidative damage. Exogenous CAT also significantly improved PLB regeneration after

Fruit production and branching density affect shoot and whole-tree wood to leaf biomass ratio in olive.

Science.gov (United States)

Rosati, Adolfo; Paoletti, Andrea; Al Hariri, Raeed; Famiani, Franco

2018-02-14

The amount of shoot stem (i.e., woody part of the shoot) dry matter per unit shoot leaf dry matter (i.e., the shoot wood to leaf biomass ratio) has been reported to be lower in short shoots than in long ones, and this is related to the greater and earlier ability of short shoots to export carbon. This is important in fruit trees, since the greater and earlier carbon export ability of shoots with a lower wood to leaf biomass ratio improves fruit production. This ratio may vary with cultivars, training systems or plant age, but no study has previously investigated the possible effect of fruit production. In this study on two olive cultivars (i.e., Arbequina, with low growth rate, and Frantoio, with high growth rate) subject to different fruit production treatments, we found that at increasing fruit production, shoot length and shoot wood to leaf biomass ratio were proportionally reduced in the new shoots growing at the same time as the fruit. Specifically, fruit production proportionally reduced total new-shoot biomass, length, leaf area and average shoot length. With decreasing shoot length, shoot diameter, stem mass, internode length, individual leaf area and shoot wood to leaf biomass ratio also decreased. This may be viewed as a plant strategy to better support fruit growth in the current year, given the greater and earlier ability of short shoots to export carbon. Moreover, at the whole-tree level, the percentage of total tree biomass production invested in leaves was closely correlated with branching density, which differed significantly across cultivars. By branching more, Arbequina concentrates more shoots (thus leaves) per unit of wood (trunk, branches and root) mass, decreasing wood to leaf biomass ratio at the whole-tree level. Therefore, while, at the shoot level, shoot length determines shoot wood to leaf biomass ratio, at the canopy level branching density is also an important determinant of whole-tree wood to leaf biomass ratio. Whole-tree wood to leaf

Pre-hospital management of mass casualty civilian shootings: a systematic literature review.

Science.gov (United States)

Turner, Conor D A; Lockey, David J; Rehn, Marius

2016-11-08

Mass casualty civilian shootings present an uncommon but recurring challenge to emergency services around the world and produce unique management demands. On the background of a rising threat of transnational terrorism worldwide, emergency response strategies are of critical importance. This study aims to systematically identify, describe and appraise the quality of indexed and non-indexed literature on the pre-hospital management of modern civilian mass shootings to guide future practice. Systematic literature searches of PubMed, Cochrane Database of Systematic Reviews and Scopus were conducted in conjunction with simple searches of non-indexed databases; Web of Science, OpenDOAR and Evidence Search. The searches were last carried out on 20 April 2016 and only identified those papers published after the 1 January 1980. Included documents had to contain descriptions, discussions or experiences of the pre-hospital management of civilian mass shootings. From the 494 identified manuscripts, 73 were selected on abstract and title and after full text reading 47 were selected for inclusion in analysis. The search yielded reports of 17 mass shooting events, the majority from the USA with additions from France, Norway, the UK and Kenya. Between 1994 and 2015 the shooting of 1649 people with 578 deaths at 17 separate events are described. Quality appraisal demonstrated considerable heterogeneity in reporting and revealed limited data on mass shootings globally. Key themes were identified to improve future practice: tactical emergency medical support may harmonise inner cordon interventions, a need for inter-service education on effective haemorrhage control, the value of senior triage operators and the need for regular mass casualty incident simulation.

Shooting Mechanisms in Nature: A Systematic Review.

Directory of Open Access Journals (Sweden)

Aimée Sakes

Full Text Available In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these mechanisms fulfill.We systematically searched the literature using Scopus and Web of Knowledge to retrieve articles about solid projectiles that either are produced in the body of the organism or belong to the body and undergo a ballistic phase. The shooting mechanisms were categorized based on the energy management prior to and during shooting.Shooting mechanisms were identified with projectile masses ranging from 1·10-9 mg in spores of the fungal phyla Ascomycota and Zygomycota to approximately 10,300 mg for the ballistic tongue of the toad Bufo alvarius. The energy for shooting is generated through osmosis in fungi, plants, and animals or muscle contraction in animals. Osmosis can be induced by water condensation on the system (in fungi, or water absorption in the system (reaching critical pressures up to 15.4 atmospheres; observed in fungi, plants, and animals, or water evaporation from the system (reaching up to -197 atmospheres; observed in plants and fungi. The generated energy is stored as elastic (potential energy in cell walls in fungi and plants and in elastic structures in animals, with two exceptions: (1 in the momentum catapult of Basidiomycota the energy is stored in a stalk (hilum by compression of the spore and droplets and (2 in Sphagnum energy is mainly stored in compressed air. Finally, the stored energy is transformed into kinetic energy of the projectile using a catapult mechanism delivering up to 4,137 J/kg in the osmotic shooting mechanism in cnidarians and 1,269 J/kg in the muscle-powered appendage strike of the mantis shrimp Odontodactylus scyllarus. The launch accelerations range from 6.6g in the frog Rana pipiens to 5,413,000g in

Sound propagation from a semi-open shooting range

NARCIS (Netherlands)

Eerden, F.J.M. van der; Berg, F. van den

2011-01-01

Semi-open shooting ranges, in contrast to a fully open shooting range, are often used in the densely populated area of the Netherlands. The Ministry of Defense operates a number of these ranges. In these shooting ranges above the line of fire a number of screens are situated for safety precautions

Water Status Related Root-to-Shoot Communication Regulates the Chilling Tolerance of Shoot in Cucumber (Cucumis sativus L.) Plants.

Science.gov (United States)

Zhang, Zi-Shan; Liu, Mei-Jun; Gao, Hui-Yuan; Jin, Li-Qiao; Li, Yu-Ting; Li, Qing-Ming; Ai, Xi-Zhen

2015-10-16

Although root-to-shoot communication has been intensively investigated in plants under drought, few studies have examined root-to-shoot communication under chilling. Here we explored whether root-to-shoot communication contributes to the chilling-light tolerance of cucumber shoots and clarified the key signal involves in this communication. After leaf discs chilling-light treatment, the photoinhibitions of Photosystem I (PSI) and Photosystem II (PSII) were similar in leaf discs of two cucumber varieties (JY-3 and JC-4). When the whole plants, including roots, were chilled under light, the photosynthetic performances in JC-4 leaves decreased more seriously than that in JY-3 leaves. However, when the water status of leaves was maintained by warming roots or floating the attached leaves on water, the PSII activity and amount of PSI in the leaves of the two varieties were similar after chilling-light treatment. In addition, the differences of PSII activities and amount of PSI between the two varieties under whole plant chilling-light treatment were independent of ABA pretreatment. Above results indicate that (1) the better water status in leaves under chilling contributes to the higher chilling tolerance of JY-3; (2) the water status, rather than an ABA signal, dominates root-to-shoot communication under chilling and the chilling tolerance of cucumber shoot.

Differentiation of shoot elements from the rachis of Secale cereale L.

Directory of Open Access Journals (Sweden)

Jan J. Rybczyński

2014-01-01

Full Text Available In vitro culture of young Secale cereale spikes is described with special attention given to changes in development of the rachis. 7 mm explants were cultivated on a modified M u r a s h i g e and S k o o g (1962 medium (MS supplemented with 2,4-D (dichlorophenoxyacetic acid, NAA (α-naph-thaleneacetic acid, IAA (β-indoleacetic acid, 2,4,5-T (trichlorophenoxyacetic acid, and ZEA (zeatin, KIN (kinetin, BAP (6-benzylaminopurine, IPA (izopentenyladenine or 2 iP in numerous combinations and concentrations. Rachises differentiated branches with node construction in the presence of synthetic auxin. Rhizogenesis of explants was stimulated by 2,4-D and 2,4,5-T. 2,4,5-T + IPA appeared to be the best combination for callus regeneration. Many meristematic centres were found previously and combinations of NAA + KIN stimulated direct, whereas 2,4-D + ZEA indirect, differentiation of shoot elements. Development was observed from plantlets to flowering plants.

Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies

Directory of Open Access Journals (Sweden)

Michiel W. Pot

2016-09-01

Full Text Available Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of mechanically inferior fibrocartilage. As a result, this technique offers only temporary clinical improvement. Tissue engineering and regenerative medicine may improve the outcome of microfracture surgery. Filling the subchondral defect with a biomaterial may provide a template for the formation of new hyaline cartilage tissue. In this study, a systematic review and meta-analysis were performed to assess the current evidence for the efficacy of cartilage regeneration in preclinical models using acellular biomaterials implanted after marrow stimulating techniques (microfracturing and subchondral drilling compared to the natural healing response of defects. The review aims to provide new insights into the most effective biomaterials, to provide an overview of currently existing knowledge, and to identify potential lacunae in current studies to direct future research. A comprehensive search was systematically performed in PubMed and EMBASE (via OvidSP using search terms related to tissue engineering, cartilage and animals. Primary studies in which acellular biomaterials were implanted in osteochondral defects in the knee or ankle joint in healthy animals were included and study characteristics tabulated (283 studies out of 6,688 studies found. For studies comparing non-treated empty defects to defects containing implanted biomaterials and using semi-quantitative histology as outcome measure, the risk of bias (135 studies was assessed and outcome data were collected for meta-analysis (151 studies. Random-effects meta-analyses were performed, using cartilage regeneration as outcome measure on an absolute 0–100% scale. Implantation of acellular

Improved cartilage regeneration by implantation of acellular biomaterials after bone marrow stimulation: a systematic review and meta-analysis of animal studies.

Science.gov (United States)

Pot, Michiel W; Gonzales, Veronica K; Buma, Pieter; IntHout, Joanna; van Kuppevelt, Toin H; de Vries, Rob B M; Daamen, Willeke F

2016-01-01

Microfracture surgery may be applied to treat cartilage defects. During the procedure the subchondral bone is penetrated, allowing bone marrow-derived mesenchymal stem cells to migrate towards the defect site and form new cartilage tissue. Microfracture surgery generally results in the formation of mechanically inferior fibrocartilage. As a result, this technique offers only temporary clinical improvement. Tissue engineering and regenerative medicine may improve the outcome of microfracture surgery. Filling the subchondral defect with a biomaterial may provide a template for the formation of new hyaline cartilage tissue. In this study, a systematic review and meta-analysis were performed to assess the current evidence for the efficacy of cartilage regeneration in preclinical models using acellular biomaterials implanted after marrow stimulating techniques (microfracturing and subchondral drilling) compared to the natural healing response of defects. The review aims to provide new insights into the most effective biomaterials, to provide an overview of currently existing knowledge, and to identify potential lacunae in current studies to direct future research. A comprehensive search was systematically performed in PubMed and EMBASE (via OvidSP) using search terms related to tissue engineering, cartilage and animals. Primary studies in which acellular biomaterials were implanted in osteochondral defects in the knee or ankle joint in healthy animals were included and study characteristics tabulated (283 studies out of 6,688 studies found). For studies comparing non-treated empty defects to defects containing implanted biomaterials and using semi-quantitative histology as outcome measure, the risk of bias (135 studies) was assessed and outcome data were collected for meta-analysis (151 studies). Random-effects meta-analyses were performed, using cartilage regeneration as outcome measure on an absolute 0-100% scale. Implantation of acellular biomaterials significantly

Characteristics of schools in which fatal shootings occur.

Science.gov (United States)

de Apodaca, Roberto Flores; Brighton, Lauren M; Perkins, Ashley N; Jackson, Kiana N; Steege, Jessica R

2012-04-01

School-based violence, and fatal school shootings in particular, have gained increased attention in the media and psychological literature. Most reports have focused on the characteristics of perpetrators, but there is a growing awareness that school-related factors may also influence the occurrence of fatal school shootings. The current study examined several key characteristics of all schools where random (38) and targeted (96) fatal shootings occurred in the United States between 1966 and 2009. These were compared with a group (138) of schools randomly selected to represent the population of all schools in the United States. The size of a school's enrollment, urban or suburban locale, public funding, and predominantly non-white enrollment were positively associated with fatal shootings. Universities and colleges were disproportionately associated with random shootings and high schools with targeted ones. It was proposed that characteristics of schools that allow feelings of anonymity or alienation among students may help create environmental conditions associated with fatal school shootings. Implications for future research and interventions are considered.

Using ground-based spectral reflectance sensors and photography to estimate shoot N concentration and dry matter of potato

DEFF Research Database (Denmark)

Zhenjiang, Zhou; Jabloun, Mohamed; Plauborg, Finn

2018-01-01

Two years experiments were set up to evaluate the performance of different vegetation indices (VI) to estimate shoot N concentration (Nc) and shoot dry matter (DM) for a potato crop grown under different nitrogen (N) treatments. Possibilities to improve the performance of VI using normalization b...

Combination of the Auxins NAA, IBA, and IAA with GA3 Improves the Commercial Seed-Tuber Production of Potato (Solanum tuberosum L.) under In Vitro Conditions

Science.gov (United States)

Kumlay, Ahmet Metin

2014-01-01

The study compared the effects of 1.0 × MS medium containing various concentrations of α-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA), alone or in combination with gibberellic acid (GA3) in micropropagation of three potato (Solanum tuberosum L.) cultivars Pasinler, Granola, and Caspar using binodal stem cuttings. The results testified improved regeneration on 1.0 × MS medium containing variants of NAA, IAA, and IBA plus GA3 on all cultivars. The minimum days to shoot induction on three cultivars ranged 4.25–5 d on 1.0 × MS medium containing 0.25 mg L−1  GA3 + 1 mg L−1 NAA. The longest shoots (11.8 cm), maximum number of nodes (13.50), and maximum number of leaves (11.00) were recorded on cv. Caspar on 1.0 × MS medium containing 1 mg L−1  NAA + 0.25 mg L−1 GA3. The minimum time to root induction (12.25 d) was noted on cv. Pasinler on the same medium. All of the regenerated shoots could be easily rooted. The results showed that the combined effect of various concentrations of NAA, IAA, and IBA plus GA3 was more pronounced compared to the auxins used alone. The results of this research are of significant importance for potato breeders. PMID:25028654

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment.

Science.gov (United States)

Allen, Peter M; Latham, Keziah; Mann, David L; Ravensbergen, Rianne H J C; Myint, Joy

2016-01-01

The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle, while standing, toward a regulation target placed at the end of a 10 m shooting range. Cambridge simulation glasses were used to simulate six different levels of VI. Visual acuity (VA) and contrast sensitivity (CS) were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual's average score in every level of simulated VI and normalizing this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving 'expected' or 'below expected' shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR) is conservative, maximizing the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not actually have an impairment that impacts performance in the sport. An

Chitosan Based Regenerated Cellulose Fibers Functionalized with Plasma and Ultrasound

Directory of Open Access Journals (Sweden)

Urška Vrabič Brodnjak

2018-04-01

Full Text Available The great potential of regenerated cellulose fibers, which offer excellent possibilities as a matrix for the design of bioactive materials, was the lead for our research. We focused on the surface modification of fibers to improve the sorption properties of regenerated cellulose and biocomposite regenerated cellulose/chitosan fibers, which are on the market. The purpose of our investigation was also the modification of regenerated cellulose fibers with the functionalization by chitosan as a means of obtaining similar properties to biocomposite regenerated cellulose/chitosan fibers on the market. Argon gas plasma was used for fiber surface activation and chitosan adsorption. Ultrasound was also used as a treatment procedure for the surface activation of regenerated cellulose fibers and treatment with chitosan. Analyses have shown that ultrasonic energy or plasma change the accessibility of free functional groups, structure and reactivity, especially in regenerated cellulose fibers. Changes that occurred in the morphology and in the structure of fibers were also reflected in their physical and chemical properties. Consequently, moisture content, sorption properties and water retention improved.

Increased needle nitrogen contents did not improve shoot photosynthetic performance of mature nitrogen-poor Scots pine trees

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Lasse Tarvainen

2016-07-01

Full Text Available Numerous studies have shown that temperate and boreal forests are limited by nitrogen (N availability. However, few studies have provided a detailed account of how carbon (C acquisition of such forests reacts to increasing N supply. We combined measurements of needle-scale biochemical photosynthetic capacities and continuous observations of shoot-scale photosynthetic performance from several canopy positions with simple mechanistic modelling to evaluate the photosynthetic responses of mature N-poor boreal Pinus sylvestris to N fertilization. The measurements were carried out in August 2013 on 90-year-old pine trees growing at Rosinedalsheden research site in northern Sweden. In spite of a nearly doubling of needle N content in response to the fertilization, no effect on the long-term shoot-scale C uptake was recorded. This lack of N-effect was due to strong light limitation of photosynthesis in all investigated canopy positions. The effect of greater N availability on needle photosynthetic capacities was also constrained by development of foliar P deficiency following N addition. Thus, P deficiency and accumulation of N in arginine appeared to contribute towards lower shoot-scale nitrogen-use efficiency in the fertilized trees, thereby additionally constraining tree-scale responses to increasing N availability. On the whole our study suggests that the C uptake response of the studied N-poor boreal P. sylvestris stand to enhanced N availability is constrained by the efficiency with which the additional N is utilized. This efficiency, in turn, depends on the ability of the trees to use the greater N availability for additional light capture. For stands that have not reached canopy closure, increase in leaf area following N fertilization would be the most effective way for improving light capture and C uptake while for mature stands an increased leaf area may have a rather limited effect on light capture owing to increased self-shading. This raises

Increased Needle Nitrogen Contents Did Not Improve Shoot Photosynthetic Performance of Mature Nitrogen-Poor Scots Pine Trees.

Science.gov (United States)

Tarvainen, Lasse; Lutz, Martina; Räntfors, Mats; Näsholm, Torgny; Wallin, Göran

2016-01-01

Numerous studies have shown that temperate and boreal forests are limited by nitrogen (N) availability. However, few studies have provided a detailed account of how carbon (C) acquisition of such forests reacts to increasing N supply. We combined measurements of needle-scale biochemical photosynthetic capacities and continuous observations of shoot-scale photosynthetic performance from several canopy positions with simple mechanistic modeling to evaluate the photosynthetic responses of mature N-poor boreal Pinus sylvestris to N fertilization. The measurements were carried out in August 2013 on 90-year-old pine trees growing at Rosinedalsheden research site in northern Sweden. In spite of a nearly doubling of needle N content in response to the fertilization, no effect on the long-term shoot-scale C uptake was recorded. This lack of N-effect was due to strong light limitation of photosynthesis in all investigated canopy positions. The effect of greater N availability on needle photosynthetic capacities was also constrained by development of foliar phosphorus (P) deficiency following N addition. Thus, P deficiency and accumulation of N in arginine appeared to contribute toward lower shoot-scale nitrogen-use efficiency in the fertilized trees, thereby additionally constraining tree-scale responses to increasing N availability. On the whole our study suggests that the C uptake response of the studied N-poor boreal P. sylvestris stand to enhanced N availability is constrained by the efficiency with which the additional N is utilized. This efficiency, in turn, depends on the ability of the trees to use the greater N availability for additional light capture. For stands that have not reached canopy closure, increase in leaf area following N fertilization would be the most effective way for improving light capture and C uptake while for mature stands an increased leaf area may have a rather limited effect on light capture owing to increased self-shading. This raises the

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.

In vitro propagation of olive (Olea europaea L.) by nodal segmentation of elongated shoots.

Science.gov (United States)

Lambardi, Maurizio; Ozudogru, Elif Aylin; Roncasaglia, Romano

2013-01-01

Olive (Olea europaea L.), long-living, ever-green fruit tree of the Old World, has been part of a traditional landscape in the Mediterranean area for centuries. Both the fruits consumed after processing and the oil extracted from the fruits are among the main components of the Mediterranean diet, widely used for salads and cooking, as well as for preserving other food. Documentations show that the ancient use of this beautiful tree also includes lamp fuel production, wool treatment, soap production, medicine, and cosmetics. However, unlike the majority of the fruit species, olive propagation is still a laborious practice. As regards traditional propagation, rooting of cuttings and grafting stem segments onto rootstocks are possible, former being achieved only when the cuttings are collected in specific periods (spring or beginning of autumn), and latter only when skilled grafters are available. In both the cases, performance of the cultivars varies considerably. The regeneration of whole plants from ovules, on the other hand, is used only occasionally. Micropropagation of olive is not easy mainly due to explant oxidation, difficulties in explant disinfection, and labor-oriented establishment of in vitro shoot cultures. However today, the progress in micropropagation technology has made available the complete protocols for several Mediterranean cultivars. This chapter describes a micropropagation protocol based on the segmentation of nodal segments obtained from elongated shoots.

Root~Shoot Growth Interactions of Sorghmn (Sorghwn Bicolor L ...

African Journals Online (AJOL)

growth. Studies on root-shoot intera'ctions in relation to mechanical impedance have only investigated the effect on shoots of ... growth regulators that may be responsible. Studies of root-shoot ... of germinating seeds to MI leaving roots in rela-.

Thermal and Structural Analysis of Micro-Fabricated Involute Regenerators

Science.gov (United States)

Qiu, Songgang; Augenblick, Jack E.

2005-02-01

Long-life, high-efficiency power generators based on free-piston Stirling engines are an energy conversion solution for future space power generation and commercial applications. As part of the efforts to further improve Stirling engine efficiency and reliability, a micro-fabricated, involute regenerator structure is proposed by a Cleveland State University-led regenerator research team. This paper reports on thermal and structural analyses of the involute regenerator to demonstrate the feasibility of the proposed regenerator. The results indicate that the involute regenerator has extremely high axial stiffness to sustain reasonable axial compression forces with negligible lateral deformation. The relatively low radial stiffness may impose some challenges to the appropriate installation of the in-volute regenerators.

Modelling and comparison studies of packed screen regenerators for active magnetocaloric refrigeration

DEFF Research Database (Denmark)

Lei, Tian; Engelbrecht, Kurt; Nielsen, K. K.

2011-01-01

In active magnetic regeneration (AMR) systems, not only the magnetocaloric properties of materials, but also the regenerator geometry plays an important role in the system performance. Packed sphere regenerators are often employed in existing prototypes, however, the characteristics such as relat...... is improved and applied to simulate the regenerators. The performance of the new regenerators is studied and compared with that of the packed sphere regenerators. Possible fabrication methods of the packed screen regenerators are also discussed....

Modelling and comparison studies of packed screen regenerators for active magnetocaloric refrigeration

DEFF Research Database (Denmark)

Lei, Tian; Engelbrecht, Kurt; Nielsen, Kaspar Kirstein

2014-01-01

In active magnetic regeneration (AMR) systems, not only the magnetocaloric properties of materials, but also the regenerator geometry plays an important role in the system performance. Packed sphere regenerators are often employed in existing prototypes, however, the characteristics such as relat...... is improved and applied to simulate the regenerators. The performance of the new regenerators is studied and compared with that of the packed sphere regenerators. Possible fabrication methods of the packed screen regenerators are also discussed....

Protocol optimization for in vitro shoot multiplication of Jackfruit ...

African Journals Online (AJOL)

Jemal

2017-01-11

Jan 11, 2017 ... Protocol optimization for in vitro shoot multiplication of ... shoot length and leaf number, whereby 2 mg/L BAP alone was found to be the best with a mean shoot .... Analysis of variance showed that the interaction between.

In vitro propagation of lnula royleana DC

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Anna Stojakowska

2011-01-01

Full Text Available A micropropagation method, through axillary shoot proliferation, was elaborated for Inula royleana DC. (Asteraceae, a medicinal plant native of Himalaya. Primary explants (cotyledonary node explants and secondary explants (node explants of in vitro regenerated shoots of the plant, inoculated on MS medium supplemented with 0.1 μM NAA and 5.0 μM kinetin, regenerated 3.4 ± 1.2 and 5.1 ± 1.9 axillary shoots per explant, respectively. The regenerated shoots were easily rooting and adapting to growth in soil.

Youth Responses to School Shootings: a Review.

Science.gov (United States)

Travers, Áine; McDonagh, Tracey; Elklit, Ask

2018-05-19

This paper aims to synthesize research relating to youth responses to school shootings between 2014 and 2017. The main questions it addresses are how such events impact young people psychologically, and what risk or protective factors may contribute to different trajectories of recovery? Recent research suggests that most young people exposed to school shootings demonstrate resilience, exhibiting no long-term dysfunction. However, a minority will experience severe and chronic symptoms. The likelihood of experiencing clinically significant reactions is influenced by pre-trauma functioning as well as peri-traumatic and post-traumatic factors. These include proximity to the trauma, peri-traumatic dissociation, post-traumatic emotional regulation difficulties, social support, and flexibility of coping styles. Research that separates the distinguishing features of young people with differing recovery styles is vital to tailor intervention. But methodological and design issues associated with such research necessitates caution in drawing conclusions. Variation in definitions and measures and the self-report nature of many of the studies are potential sources of bias. Greater uniformity across designs would enhance confidence and allow for improved evidence-based intervention.

Inheritance of Resistance to Sorghum Shoot Fly, Atherigona soccata in Sorghum, Sorghum bicolor (L. Moench

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Mohammed eRiyazaddin

2016-04-01

Full Text Available Host plant resistance is one of the major components to control sorghum shoot fly, Atherigona soccata. To understand the nature of gene action for inheritance of shoot fly resistance, we evaluated 10 parents, 45 F1’s and their reciprocals in replicated trials during the rainy and postrainy seasons. Genotypes ICSV 700, Phule Anuradha, ICSV 25019, PS 35805, IS 2123, IS 2146 and IS 18551 exhibited resistance to shoot fly damage across seasons. Crosses between susceptible parents were preferred for egg laying by the shoot fly females, resulting in a susceptible reaction. ICSV 700, ICSV 25019, PS 35805, IS 2123, IS 2146 and IS 18551 exhibited significant and negative general combining ability (gca effects for oviposition, deadheart incidence, and overall resistance score. The plant morphological traits associated with expression of resistance/ susceptibility to shoot fly damage such as leaf glossiness, plant vigor, and leafsheath pigmentation also showed significant gca effects by these genotypes, suggesting the potential for use as a selection criterion to breed for resistance to shoot fly, A. soccata. ICSV 700, Phule Anuradha, IS 2146 and IS 18551 with significant positive gca effects for trichome density can also be utilised in improving sorghums for shoot fly resistance. The parents involved in hybrids with negative specific combining ability (sca effects for shoot fly resistance traits can be used in developing sorghum hybrids with adaptation to postrainy season. The significant reciprocal effects of combining abilities for oviposition, leaf glossy score and trichome density suggested the influence of cytoplasmic factors in inheritance of shoot fly resistance. Higher values of variance due to sca (σ2s, dominance variance (σ2d, and lower predictability ratios than the variance due to gca (σ2g and additive variance (σ2a for shoot fly resistance traits indicated the predominance of dominance type of gene action, whereas trichome density, leaf

Micropropagation of Asparagus by in vitro shoot culture.

Science.gov (United States)

Stajner, Nataša

2013-01-01

Asparagus officinalis is most extensively studied species within the genus Asparagus, which is well known as garden asparagus. This species is dioecious with unisexual flowers, which means that generative propagation gives roughly equal number of male and female plants. Male plants are high yielders and preferred commercially over female plants. Tissue culture techniques could efficiently promote vegetative propagation of male plants and pave the way for efficient plant breeding.This chapter describes an efficient micropropagation protocol for developing rapid growing in vitro Asparagus shoot cultures. The source of explants, inoculation, and shoot proliferation, followed by shoot propagation, rooting, and acclimatization is described. The optimal medium for Asparagus micropropagation described in this chapter is composed of MS macro- and microelements and a combination of auxins and cytokinins. Plant growth regulators NAA, kinetin, and BA were used in various concentrations. Three different media representing the whole micropropagation protocol of Asparagus are described; medium for shoot initiation, medium for shoot multiplication, and medium for root formation. By in vitro propagation of Asparagus, root initiation is difficult, but can be promoted by adding growth retardant ancymidol which also greatly promotes shoot development and suppresses callus formation.

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

Transformation of Oats and Its Application to Improving Osmotic Stress Tolerance

Science.gov (United States)

Maqbool, Shahina B.; Zhong, Heng; Oraby, Hesham F.; Sticklen, Mariam B.

Oat (Avena sativa L.), a worldwide temperate cereal crop, is deficient in tolerance to osmotic stress due to drought and/or salinity. To genetically transform the available commercial oat cultivars, a genotype-independent and efficient regeneration system from shoot apical meristems was developed using four oat cultivars: Prairie, Porter, Ogle, and Pacer. All these oat cultivars generated a genotype-independent in vitro differentiated multiple shoots from shoot apical meristems at a high frequency. Using this system, three oat cultivars were genetically co-transformed with pBY520 (containing hva1 and bar) and pAct1-D (containing gus) using biolistic™ bombardment. Transgenic plants were selected and regenerated using herbicide resistance and GUS as a marker. Molecular and biochemical analyses of putative transgenic plants confirmed the co-integration of hva1 and bar genes with a frequency of 100%, and 61.6% of the transgenic plants carried all three genes (hva1, bar and gus). Further analyses of R0, R1, and R2 progenies confirmed stable integration, expression, and Mendalian inheritance for all transgenes. Histochemical analysis of GUS protein in transgenic plants showed a high level of GUS expression in vascular tissues and in the pollen grains of mature flowers. Immunochemical analysis of transgenic plants indicated a constitutive expression of hva1 at all developmental stages. However, the level of HVA1 was higher during the early seedling stages.

Mass propagation of shoots of Stevia rebaudiana using a large scale bioreactor.

Science.gov (United States)

Akita, M; Shigeoka, T; Koizumi, Y; Kawamura, M

1994-01-01

A procedure for the mass propagation of multiple shoots of Stevia rebaudiana is described. Isolated shoot primordia were used as the inoculum to obtain clusters of shoot primordia. Such clusters were grown in a 500 liter bioreactor to obtain shoots. A total of 64.6 Kg of shoots were propagated from 460 g of the inoculated shoot primordia. These shoots were easily acclimatized in soil.

Comparison of detectability in step-and-shoot mode and continuous mode digital tomosynthesis systems

Science.gov (United States)

Lee, Changwoo; Han, Minah; Baek, Jongduk

2017-03-01

Digital tomosynthesis system has been widely used in chest, dental, and breast imaging. Since the digital tomosynthesis system provides volumetric images from multiple projection data, structural noise inherent in X-ray radiograph can be reduced, and thus signal detection performance is improved. Currently, tomosynthesis system uses two data acquisition modes: step-and-shoot mode and continuous mode. Several studies have been conducted to compare the system performance of two acquisition modes with respect to spatial resolution and contrast. In this work, we focus on signal detectability in step-and-shoot mode and continuous mode. For evaluation, uniform background is considered, and eight spherical objects with diameters of 0.5, 0.8, 1, 2, 3, 5, 8, 10 mm are used as signals. Projection data with and without spherical objects are acquired in step-and-shoot mode and continuous mode, respectively, and quantum noise are added. Then, noisy projection data are reconstructed by FDK algorithm. To compare the detection performance of two acquisition modes, we calculate task signal-to-noise ratio (SNR) of channelized Hotelling observer with Laguerre-Gauss channels for each spherical object. While the task-SNR values of two acquisition modes are similar for spherical objects larger than 1 mm diameter, step-and-shoot mode yields higher detectability for small signal sizes. The main reason of this behavior is that small signal is more affected by X-ray tube motion blur than large signal. Our results indicate that it is beneficial to use step-and-shoot data acquisition mode to improve the detectability of small signals (i.e., less than 1 mm diameter) in digital tomosynthesis systems.

Accurate inference of shoot biomass from high-throughput images of cereal plants

Directory of Open Access Journals (Sweden)

Tester Mark

2011-02-01

Full Text Available Abstract With the establishment of advanced technology facilities for high throughput plant phenotyping, the problem of estimating plant biomass of individual plants from their two dimensional images is becoming increasingly important. The approach predominantly cited in literature is to estimate the biomass of a plant as a linear function of the projected shoot area of plants in the images. However, the estimation error from this model, which is solely a function of projected shoot area, is large, prohibiting accurate estimation of the biomass of plants, particularly for the salt-stressed plants. In this paper, we propose a method based on plant specific weight for improving the accuracy of the linear model and reducing the estimation bias (the difference between actual shoot dry weight and the value of the shoot dry weight estimated with a predictive model. For the proposed method in this study, we modeled the plant shoot dry weight as a function of plant area and plant age. The data used for developing our model and comparing the results with the linear model were collected from a completely randomized block design experiment. A total of 320 plants from two bread wheat varieties were grown in a supported hydroponics system in a greenhouse. The plants were exposed to two levels of hydroponic salt treatments (NaCl at 0 and 100 mM for 6 weeks. Five harvests were carried out. Each time 64 randomly selected plants were imaged and then harvested to measure the shoot fresh weight and shoot dry weight. The results of statistical analysis showed that with our proposed method, most of the observed variance can be explained, and moreover only a small difference between actual and estimated shoot dry weight was obtained. The low estimation bias indicates that our proposed method can be used to estimate biomass of individual plants regardless of what variety the plant is and what salt treatment has been applied. We validated this model on an independent

Enhanced in vitro multiple shoot induction in elite Pakistani guava ...

African Journals Online (AJOL)

Elite guava (Psidium guajava L.) strains of cv. Safeda were explored in vitro for multiple shoot induction. Shoot induction was enhanced up to 83% with 3.5 to 4.25 shoots per single node cutting and shoot tip explants, respectively, using higher levels of benzyl amino purine (BAP) in Murashige and Skoog (MS) medium.

Shoot growth of Merlot and Cabernet Sauvignon grapevine varieties

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Marcelo Borghezan

2012-02-01

Full Text Available The objective of this work was to evaluate shoot growth of the grapevine varieties Merlot and Cabernet Sauvignon, during 2006/2007, and Cabernet Sauvignon, during 2008/2009, in São Joaquim, SC, Brazil. The experiment was carried out in a commercial vineyard trained on a vertical trellis system. The shoots of the central part of the plants were selected, and the lengths from the base to the apex of 20 shoots per cultivar were evaluated. In 2006/2007, monitoring began at pruning, on 9/15/2006, and ended on 2/6/2007, totalizing 144 days of evaluation. During the 2008/2009 cycle, phenology and shoot growth for 'Cabernet Sauvignon' were assessed from grape development (1/13/2009 (pea-sized grapes until shoot vegetative growth had ceased. Budburst occurred in the second half of September, and shoot-growth cessation occurred during ripening. Higher growth rates (about 4 cm per day were observed in pre- and post-flowering, followed by reduction due to the competition for photosynthates for the formation of flowers and bunches. Temperature and photoperiod induce grapevine shoots to cease growth in the highland regions of Santa Catarina State, Brazil.

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting With Vision Impairment

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Peter M Allen

2016-11-01

Full Text Available The aim of this study was to investigate the level of vision impairment that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI shooting. Nineteen international-level shooters without vision impairment took part in the study. Participants shot an air rifle, while standing, towards a regulation target placed at the end of a 10m shooting range. Cambridge simulation glasses were used to simulate six different levels of vision impairment. Visual acuity (VA and contrast sensitivity (CS were assessed along with shooting performance in each of seven conditions of simulated impairment and compared to that with habitual vision. Shooting performance was evaluated by calculating each individual’s average score in every level of simulated vision impairment and normalising this score by expressing it as a percentage of the baseline performance achieved with habitual vision. Receiver Operating Characteristic (ROC curves were constructed to evaluate the ability of different VA and CS cut-off criteria to appropriately classify these athletes as achieving ‘expected’ or ‘below expected’ shooting results based on their performance with different levels of VA and CS. Shooting performance remained relatively unaffected by mild decreases in VA and CS, but quickly deteriorated with more moderate losses. The ability of visual function measurements to classify shooting performance was good, with 78% of performances appropriately classified using a cut-off of 0.53 logMAR and 74% appropriately classified using a cut-off of 0.83 logCS. The current inclusion criteria for VI shooting (1.0 logMAR is conservative, maximising the chance of including only those with an impairment that does impact performance, but potentially excluding some who do have a genuine impairment in the sport. A lower level of impairment would include more athletes who do have a genuine impairment but would potentially include those who do not

Arabidopsis CDS blastp result: AK119645 [KOME

Lifescience Database Archive (English)

Full Text Available PF|00847 AP2 domain; identical to cDNA enhancer of shoot regeneration ESR1 GI:18028939, enhancer of shoot regeneration ESR1 [Arabidopsis thaliana] GI:18028940 1e-10 ... ...ve / enhancer of shoot regeneration (ESR1) similar to gb|D38124 EREBP-3 from Nicotiana tabacum and contains ...AK119645 002-130-G05 At1g12980.1 AP2 domain-containing transcription factor, putati

IN VITRO REGENERATION OF THREE CHRYSANTHEMUM (Dendrathema grandiflora VARIETIES “VIA” ORGANOGENESIS AND SOMATIC EMBRYOGENESIS

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Elizabeth Hodson de Jaramillo

2008-09-01

Full Text Available Chrysanthemum (Dendrathema grandiflora has a high demand in the Colombian and international cut flower markets.Since commercial production of this ornamental species is strongly affected by fungal diseases such as chrysanthemumwhite rust (Puccinia horiana, high doses of fungicides are being used posing increased environmental and commercialcosts. Assessment of in vitro regeneration systems from leaf discs was a first step in developing a plant genetic transformationprotocol to obtain fungi-resistant plants. Leaf discs of White Albatross, Yellow Albatross, and Escapade varieties wereestablished in vitro on MS medium supplemented with NAA (0 - 4.83 μM and BAP (0 - 13.32 μM alone and incombination. Leaf discs were also cultured on MumB medium containing 2,4-D (0 - 4.52 μM for 7, 14, and 21 days priorto their transferral to a 2,4-D free MumB medium. Regenerated shoots were individualized, rooted, and hardened. Resultsshow that MS with 4.83 μM NAA + 4.44 μM BAP and 4.83 μM NAA + 13.32 μM BAP induce organogenesis, and MumBwith 2.26 μM 2,4-D induces somatic embryogenesis on all three varieties, with exposition periods to 2,4-D of 14 days forWhite Albatross and 21 days for Yellow Albatross and Escapade. Shoot development from somatic embryos was observedin the three varieties when cultured on a 2,4-D free MumB medium. Spontaneous rooting was recorded in 85% of the shootsthus facilitating hardening and successful transfer to soil.

Liquid shoot culture of Salvia officinalis L. for micropropagation and production of antioxidant compounds; effect of triacontanol

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Izabela Grzegorczyk

2011-01-01

Full Text Available Liquid shoot culture of Salvia officinalis L. in MS medium containing IAA (0.1 mg l-1 and BAP (0.45 mg l-1 was developed and evaluated in relation to shoot multiplication and antioxidant compound (carnosic acid, carnosol and rosmarinic acid accumulation. In the liquid medium, on average, 3 new shoots per explant (shoot tip were obtained within 3 weeks. The shoots produced 8.2±0.02 mg of diterpenoids and 31.2±0.29 mg of rosmarinic acid per gram of dry weight. Shoot proliferation and diterpenoid content increased when triacontanol (5, 10 or 20 pg l-1 was added to the liquid medium. In optimum conditions (at 20 pg l-1 TRIA almost 7 shoots were formed per explant after 3 weeks. An increase in diterpenoid production (expressed as the sum of carnosol and carnosic acid ranged from 30% to 50% and dependended on triacontanol concentration tested. The level of diterpenoids in triacontanol-treated shoots was similar to the content of compounds in commercial herbal product (dried leaves of S. officinalis (10-12 mg g-1 dry wt. Triacontanol did not increase rosmarinic acid production, but the content of the phenolic as compound in shoots grown in liquid culture (31 mg g-1 dry wt was even 24 times higher compared to samples of dried leaves of S. officinalis plants. We also demonstrated that the highest amounts of CA, Car and RA were accumulated in young, top parts of sage shoots. This observation could be useful for improving the selection of material for the extraction of natural antioxidants from S. officinalis.

Bone regeneration with biomaterials and active molecules delivery.

Science.gov (United States)

D' Este, Matteo; Eglin, David; Alini, Mauro; Kyllonen, Laura

2015-01-01

The combination of biomaterials and drug delivery strategies is a promising avenue towards improved synthetic bone substitutes. With the delivery of active species biomaterials can be provided with the bioactivity they still lack for improved bone regeneration. Recently, a lot of research efforts have been put towards this direction. Biomaterials for bone regeneration have been supplemented with small or biological molecules for improved osteoprogenitor cell recruitment, osteoinductivity, anabolic or angiogenic response, regulation of bone metabolism and others. The scope of this review is to summarize the most recent results in this field.

Structure–Function Relationships in Highly Modified Shoots of Cactaceae

Science.gov (United States)

MAUSETH, JAMES D.

2006-01-01

• Background and Aims Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. • Scope Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus ‘flower’ is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels. PMID:16820405

Structure-function relationships in highly modified shoots of cactaceae.

Science.gov (United States)

Mauseth, James D

2006-11-01

Cacti are extremely diverse structurally and ecologically, and so modified as to be intimidating to many biologists. Yet all have the same organization as most dicots, none differs fundamentally from Arabidopsis or other model plants. This review explains cactus shoot structure, discusses relationships between structure, ecology, development and evolution, and indicates areas where research on cacti is necessary to test general theories of morphogenesis. Cactus leaves are diverse; all cacti have foliage leaves; many intermediate stages in evolutionary reduction of leaves are still present; floral shoots often have large, complex leaves whereas vegetative shoots have microscopic leaves. Spines are modified bud scales, some secrete sugar as extra-floral nectaries. Many cacti have juvenile/adult phases in which the flowering adult phase (a cephalium) differs greatly from the juvenile; in some, one side of a shoot becomes adult, all other sides continue to grow as the juvenile phase. Flowers are inverted: the exterior of a cactus 'flower' is a hollow vegetative shoot with internodes, nodes, leaves and spines, whereas floral organs occur inside, with petals physically above stamens. Many cacti have cortical bundles vascularizing the cortex, however broad it evolves to be, thus keeping surface tissues alive. Great width results in great weight of weak parenchymatous shoots, correlated with reduced branching. Reduced numbers of shoot apices is compensated by great increases in number of meristematic cells within individual SAMs. Ribs and tubercles allow shoots to swell without tearing during wet seasons. Shoot epidermis and cortex cells live and function for decades then convert to cork cambium. Many modifications permit water storage within cactus wood itself, adjacent to vessels.

Millet's Shooting Stars

Science.gov (United States)

Beech, M.

1988-12-01

In this essay two paintings by the French artist Jean-Francois Millet are described. These paintings, Les Etoiles Filantes and Nuit Etoilée are particularly interesting since they demonstrate the rare artistic employment of the shooting-star image and metaphor.

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)

3D printing strategies for peripheral nerve regeneration.

Science.gov (United States)

Petcu, Eugen B; Midha, Rajiv; McColl, Erin; Popa-Wagner, Aurel; Chirila, Traian V; Dalton, Paul D

2018-03-23

After many decades of biomaterials research for peripheral nerve regeneration, a clinical product (the nerve guide), is emerging as a proven alternative for relatively short injury gaps. This review identifies aspects where 3D printing can assist in improving long-distance nerve guide regeneration strategies. These include (1) 3D printing of the customizable nerve guides, (2) fabrication of scaffolds that fill nerve guides, (3) 3D bioprinting of cells within a matrix/bioink into the nerve guide lumen and the (4) establishment of growth factor gradients along the length a nerve guide. The improving resolution of 3D printing technologies will be an important factor for peripheral nerve regeneration, as fascicular-like guiding structures provide one path to improved nerve guidance. The capability of 3D printing to manufacture complex structures from patient data based on existing medical imaging technologies is an exciting aspect that could eventually be applied to treating peripheral nerve injury. Ultimately, the goal of 3D printing in peripheral nerve regeneration is the automated fabrication, potentially customized for the patient, of structures within the nerve guide that significantly outperform the nerve autograft over large gap injuries.

Thermodynamic analysis of a Stirling engine including regenerator dead volume

Energy Technology Data Exchange (ETDEWEB)

Puech, Pascal; Tishkova, Victoria [Universite de Toulouse, UPS, CNRS, CEMES, 29 rue Jeanne Marvig, F-31055 Toulouse (France)

2011-02-15

This paper provides a theoretical investigation on the thermodynamic analysis of a Stirling engine with linear and sinusoidal variations of the volume. The regenerator in a Stirling engine is an internal heat exchanger allowing to reach high efficiency. We used an isothermal model to analyse the net work and the heat stored in the regenerator during a complete cycle. We show that the engine efficiency with perfect regeneration doesn't depend on the regenerator dead volume but this dead volume strongly amplifies the imperfect regeneration effect. An analytical expression to estimate the improvement due to the regenerator has been proposed including the combined effects of dead volume and imperfect regeneration. This could be used at the very preliminary stage of the engine design process. (author)

Production of polyploids from cultured shoot tips of Eucalyptus ...

African Journals Online (AJOL)

Polyploids from cultured shoot tips of Eucalyptus globulus were produced by treatment with colchicine. Results showed that the combination of 0.5% colchicine and treating multiple shoot clumps for 4 days was the most appropriate conditions for E. globulus polyploidy induction and the effect of the use of multiple shoot ...

Metabolic changes associated with shoot formation in tobacco callus cultures

Energy Technology Data Exchange (ETDEWEB)

Grady, K.L.

1982-08-01

Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in (U-/sup 14/C)sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with (U-/sup 14/C)sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references.

Metabolic changes associated with shoot formation in tobacco callus cultures

International Nuclear Information System (INIS)

Grady, K.L.

1982-08-01

Callus tissue derived from Nicotiana tabacum L. stem pith parenchyma cells was grown either on medium which maintains the callus in an undifferentiated state, or on medium which induces the formation of shoots. Two complementary types of studies were performed with the goal of establishing metabolic markers for the initiation of shoot formation: one designed to characterize the flow of radioactive sucrose into various metabolic pools, and one which allowed measurement of intermediary metabolite concentrations. In the former, callus tissue was incubated in [U- 14 C]sucrose for periods up to one hour, and patterns of metabolite labelling in tissue grown on shoot-forming and non-shoot-forming media were compared. In the latter studies, tissue was grown for an entire subculture period on non-shoot-forming medium labelled with [U- 14 C]sucrose, then subcultured to labelled non-shoot-forming or shoot-forming media, and sampled at intervals during the first week of growth. 189 references

Shooting mechanisms in Nature : A systematic review

NARCIS (Netherlands)

Sakes, A.; van der Wiel, M.; Henselmans, P.W.J.; van Leeuwen, J.L.; Dodou, D.; Breedveld, P.

2016-01-01

Background
In nature, shooting mechanisms are used for a variety of purposes, including prey capture, defense, and reproduction. This review offers insight into the working principles of shooting mechanisms in fungi, plants, and animals in the light of the specific functional demands that these

Cell fate regulation in the shoot meristem.

Science.gov (United States)

Laux, T; Mayer, K F

1998-04-01

The shoot meristem is a proliferative centre containing pluripotent stem cells that are the ultimate source of all cells and organs continuously added to the growing shoot. The progeny of the stem cells have two developmental options, either to renew the stem cell population or to leave the meristem and to differentiate, possibly according to signals from more mature tissue. The destiny of each cell depends on its position within the dynamic shoot meristem. Genetic data suggest a simple model in which graded positional information is provided by antagonistic gene functions and is interpreted by genes which regulate cell fate.

Development of an improved attractive lure for the pine shoot beetle, Tomicus piniperda (Coleoptera: Scolytidae)

Science.gov (United States)

Therese M. Poland; Peter de Groot; Stephen Burke; David Wakarchuk; Robert A. Haack; Reginald Nott; Taylor Scarr

2003-01-01

1) The pine shoot beetle, Tomicus piniperda (L.) (Coleoptera: Scolytidae), is an exotic pest of pine, Pinus spp., and was first discovered in North America in 1992. 2) Although primary attraction to host volatiles has been clearly demonstrated for T. piniperda, the existence and role of secondary attraction to...

Radiographing roots and shoots

International Nuclear Information System (INIS)

Shariffah Noor Khamseah Al Idid

1985-01-01

The effect of seed orientation on germination time and on shoot and root growth patterns is studied. Neutron radiography is used to observe the development of 4 types of plants, maize, greenpea, soya bean and padi. These plants were grown in varying orientations; sand sizes, sand thicknesses, and level of water content. Radiography of the seeds and plants were obtained for time exposure ranging from 3-12 hours and at reactor thermal power level, ranging from 500-750 kilowatts. Results obtained showed that seeds planted in varying orientations need different length of time for shoot emergence. Neutron radiography is now developed to other areas of non-industrial applications in Malaysia. (A.J.)

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.

Accuracy of Skill Performance in the Basketball Free Throw Shooting

Directory of Open Access Journals (Sweden)

Igawa Shoji

2011-12-01

Full Text Available The purpose of this study were to investigates how timing of shot of skilled player and assess performance accuracy of free throw shooting. Ten college students participated in this study (5 skilled players, and 5 naïve participants aged 18-23 years. They performed free throw shooting at 10 times. Shooting seen was recorded three cameras and analyzed shooting successful rate, off-target distance (the distance between the basketball through point and the center of the goal and shot timing. Shot timing was not significant difference. Shooting successful rate of skilled players was higher than unskilled players. Offtarget distance of skilled players was significant smaller than naive player. Consequently, skilled player is possible to aim at the center of the goal and shooting near the center of goal.

Journalism and School Shootings in Finland 2007 -2008

OpenAIRE

Raittila, Pentti; Koljonen, Kari; Väliverronen, Jari

2010-01-01

Two school shootings in Finland (Jokela in 2007 and Kauhajoki in 2008) resulted in the death of 20 people, and they shook not only the foundations of Finnish society but also of the profession that reported about the tragedies. This report is based on research conducted on school shootings at the University of Tampere Journalism Research and Development Centre between 2008 and 2009. The analysis concentrates on both the journalistic texts published on the shootings and journalists' actions...

Grazing management that regenerates ecosystem function and ...

African Journals Online (AJOL)

Grazing management that regenerates ecosystem function and grazingland ... in ecosystem improvement, productivity, soil carbon and fertility, water-holding ... for sufficient time to produce resource improvement, sound animal production, and ...

Defense.gov Special Report: Fort Hood Shooting

Science.gov (United States)

identify possible insider threats, Army Secretary John M. McHugh told lawmakers. Story Obama: Soldiers ," Army Secretary John M. McHugh told lawmakers. Story President Praises Swift Response to Fort Hood Remarks on Fort Hood Shooting at White House McHugh, Odierno Address Fort Hood Shooting Before Congress

Lead pollution of shooting range soils | Sehube | South African ...

African Journals Online (AJOL)

Atotal of eight military shooting ranges were used for this study. Soil samples were collected at each of the eight shooting ranges at the berm, target line, 50 and 100 m from berm. In all of the shooting ranges investigated the highest total lead (Pb) concentrations were found in the bermsoils. Elevated Pb concentrations of 38 ...

Theoretical study for solar air pretreatment collector/regenerator

Energy Technology Data Exchange (ETDEWEB)

Peng Donggen; Zhang Xiaosong; Yin Yonggao [School of Energy and Environment, Southeast Univ., Nanjing (China)

2008-07-01

A new liquid regeneration equipment - solar air pretreatment collector/regenerator for liquid desiccant cooling system is put forward in this paper, which is preferable to solution regeneration in hot and moist climate in South China. The equipment can achieve liquid regeneration in lower temperature. When the solution and the air are in ''match'' state in collector/ regenerator, a match air to salt mass ratio ASMR* is found by theoretical study in which there is the largest theoretical storage capacity SC{sub max}. After two new concepts of the effective solution proportion (EPS) and the effective storage capacity (ESC) are defined, it is found by theoretical calculation that when ESP drops from 100% to 67%, ESC raises lowly, not drops and liquid outlet concentration C{sub str} {sub sol} increases from 40% to 49% in which its increment totals to 90%. All these data explain fully that air pretreatment liquid regeneration equipment enables to improve the performance of liquid desiccant cooling system. (orig.)

Contagion in Mass Killings and School Shootings.

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Sherry Towers

Full Text Available Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts.Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed. We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event.We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015. We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001. All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

Contagion in Mass Killings and School Shootings.

Science.gov (United States)

Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos

2015-01-01

Several past studies have found that media reports of suicides and homicides appear to subsequently increase the incidence of similar events in the community, apparently due to the coverage planting the seeds of ideation in at-risk individuals to commit similar acts. Here we explore whether or not contagion is evident in more high-profile incidents, such as school shootings and mass killings (incidents with four or more people killed). We fit a contagion model to recent data sets related to such incidents in the US, with terms that take into account the fact that a school shooting or mass murder may temporarily increase the probability of a similar event in the immediate future, by assuming an exponential decay in contagiousness after an event. We find significant evidence that mass killings involving firearms are incented by similar events in the immediate past. On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days, and incites an average of at least 0.22 new incidents (p = 0.0001). All p-values are assessed based on a likelihood ratio test comparing the likelihood of a contagion model to that of a null model with no contagion. On average, mass killings involving firearms occur approximately every two weeks in the US, while school shootings occur on average monthly. We find that state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings.

The effect of triacontanol on shoot multiplication and production of antioxidant compounds in shoot cultures of Salvia officinalis L.

Directory of Open Access Journals (Sweden)

Izabela Grzegorczyk

2011-01-01

Full Text Available This report describes the effect of triacontanol on shoot multiplication and production of antioxidant compounds (carnosic acid, carnosol and rosmarinic acid in S. officinalis cultures grown on MS basal medium (agar solidified medium supplemented with 0.1 mg l-1 IAA, 0.45 mg l-1 BAP. It was found that shoot proliferation significantly increased when triacontanol at concentrations of 5, 10 or 20 µg l-1 was added to the medium. HPLC analysis of acetone and methanolic extracts of sage shoots showed that the production of diterpenoids, carnosic acid/carnosol ratio, as well as, contents of rosmarinic acid were also affected by the treatment with triacontanol. The highest stimulation effect of triacontanol was observed on the production of carnosol, where the treatment with 20 µg l l-1 increased the content of this diterpenoid 4.5-fold compared to that in the control (sage shoots growing on MS basal medium, only.

Australian Mass Shootings: An Analysis of Incidents and Offenders.

Science.gov (United States)

McPhedran, Samara

2017-06-01

Mass shooting events are relatively underresearched, and most study comes from the United States. Despite significant international interest, little is known about other countries' experiences of these events. The current study examines Australian mass shooting incidents and offenders, with emphasis on mental illness, life strains, and offenders' life histories. Australia had 14 mass shootings between 1964 and 2014. Most offenders experienced acute life stressors and/or chronic strains leading up to the event; however, diagnosed mental illness was less commonly documented. These observations provide new information about mass shooting incidents and offenders, and can help to inform international policy development.

Shooting stars

International Nuclear Information System (INIS)

Maurette, M.; Hammer, C.

1985-01-01

A shooting star passage -even a star shower- can be sometimes easily seen during moonless black night. They represent the partial volatilization in earth atmosphere of meteorites or micrometeorites reduced in cosmic dusts. Everywhere on earth, these star dusts are searched to be gathered. This research made one year ago on the Greenland ice-cap is this article object; orbit gathering projects are also presented [fr

School shootings during 2013-2015 in the USA.

Science.gov (United States)

Kalesan, Bindu; Lagast, Kinan; Villarreal, Marcos; Pino, Elizabeth; Fagan, Jeffrey; Galea, Sandro

2017-10-01

Data on the factors associated with school shootings in the USA are limited. The public conversation has often suggested several factors that may be linked to these events, however with little empirical support. Aiming to fill this gap, we describe the characteristics of school shooting incidents in the USA between 2013 and 2015 and explore whether four factors that represent domains of firearm policy, educational policy and epidemiological risk factors for intentional firearm injuries-background check (BC) policies, per capita mental health expenditures (MHE), K-12 education expenditure (KEE) and urbanicity-were associated with school shootings during this period. We searched LexisNexis, a newspaper and broadcast media databases for school shooting incidents from 1 January 2013 to 31 December 2015. Presence of BC laws was extracted from legal information in LexisNexis. State-level covariates of per capita MHE (2013), KEE (2013) and urbanicity (2010) rates were obtained from publicly available data sources. We used negative binomial regression models accounting for clustering by state to explore unadjusted associations between the BC laws, state-level covariates and school shootings to report IRR and 95% CI. We documented 154 school shootings (35, 55 and 64 each year). In unadjusted models, BC for firearm purchase (IRR=0.55, 95% CI 0.39 to 0.76), ammunition purchase (IRR=0.11, 95% CI 0.05 to 0.27), log per capita MHE (IRR=0.58, 95% CI 0.37 to 0.90), log per-capita KEE (IRR=0.09, 9% CI 0.02 to 0.29) and urbanicity (IRR=0.97, 95% CI 0.96 to 0.99) were associated with school shooting. School shootings are less likely in states with BC laws, higher MHE and KEE, and with greater per cent urban population. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Evaluación y selección de un protocolo para la regeneración in vitro de la variedad de tomate Unapal-Arreboles Evaluation and selection of a protocol for in vitro regeneration of tomato variety Unapal-Arreboles

Directory of Open Access Journals (Sweden)

Hernando Ramírez

2009-01-01

Full Text Available Se compararon tres medios de cultivo para seleccionar el apropiado para la regeneración in vitro de la variedad de tomate UNAPAL-Arreboles. Se evaluó la producción de callos/explante, brotes/explante y plántulas /explante. El análisis de varianza y la prueba de Duncan permitieron concluir que el medio M3 presentó los mejores promedios para las variables evaluadas.The main objective of this research was to carried out the comparison of three culture medium of major use for in vitro regeneration of tomato, to select the more appropriate medium for in vitro regeneration of tomato, variety UNAPAL-Arreboles. The analysis of variance and media comparison was made based on the callus, shoots and plantlets production. The highest efficiency of callus, shoots and plantlets production was obtained with the M3 media.

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

High frequency organogenesis in hypocotyl, cotyledon, leaf and petiole explants of broccoli (Brassica oleracea L. var. italica), an important vegetable crop.

Science.gov (United States)

Kumar, Pankaj; Srivastava, D K

2015-04-01

Broccoli (Brassica oleracea L. var. italica) is an important, nutritionally rich vegetable crop, but severely affected by environmental stresses, pests and diseases which cause massive yield and quality losses. Genetic manipulation is becoming an important method for broccoli improvement. In the present study, a reproducible and highly efficient protocol for obtaining organogenesis from hypocotyl, cotyledon, leaf and petiole explants of broccoli (Brassica oleracea L. var. italica cv. Solan green head) has been developed. Hypocotyl and cotyledon explants were used from 10 to 12 days old aseptically grown seedlings whereas leaf and petiole explants were excised from 18 to 20 days old green house grown seedlings and surface sterilized. These explants were cultured on shoot induction medium containing different concentration and combination of BAP and NAA. High efficiency shoot regeneration has been achieved in hypocotyl (83.33 %), cotyledon (90.11 %), leaf (62.96 %) and petiole (91.10 %) explants on MS medium supplemented with 3.5 mg/l BAP + 0.019 mg/l NAA 2.5 mg/l BAP + 0.5 mg/l NAA, 4.0 mg/l BAP + 0.5 mg/l NAA and 4.5 mg/l BAP + 0.019 mg/l NAA respectively. Petiole explants showed maximum shoot regeneration response as compared to other explants. MS medium supplemented with 0.10 mg/l NAA was found best for root regeneration (100 %) from in vitro developed shoots. The regenerated complete plantlets were transferred to the pots containing cocopeat and successfully acclimatized. This optimized regeneration protocol can be efficiently used for genetic transformation in broccoli. This is the first comparative report on multiple shoot induction using four different types of explants viz. hypocotyl, cotyledon, leaf and petiole.

Nanoparticles for tendon healing and regeneration: literature review.

Directory of Open Access Journals (Sweden)

Paolo Domenico Parchi

2016-08-01

Full Text Available Tendon injuries are commonly met in the emergency department. Unfortunately, tendon tissue has limited regeneration potential and usually the consequent formation of scar tissue causes inferior mechanical properties Nanoparticles could be used in different way to improve tendon healing and regeneration, ranging from scaffolds manufacturing (increasing the strength and endurance or anti-adhesions, anti-microbial and anti-inflammatory properties to gene therapy. This paper aims to summarize the most relevant studies showing the potential application of nanoparticles for tendon tissue regeneration

The Mental Health Consequences of Mass Shootings.

Science.gov (United States)

Lowe, Sarah R; Galea, Sandro

2017-01-01

Mass shooting episodes have increased over recent decades and received substantial media coverage. Despite the potentially widespread and increasing mental health impact of mass shootings, no efforts to our knowledge have been made to review the empirical literature on this topic. We identified 49 peer-reviewed articles, comprised of 27 independent samples in the aftermath of 15 mass shooting incidents. Based on our review, we concluded that mass shootings are associated with a variety of adverse psychological outcomes in survivors and members of affected communities. Less is known about the psychological effects of mass shootings on indirectly exposed populations; however, there is evidence that such events lead to at least short-term increases in fears and declines in perceived safety. A variety of risk factors for adverse psychological outcomes have been identified, including demographic and pre-incident characteristics (e.g., female gender and pre-incident psychological symptoms), event exposure (e.g., greater proximity to the attack and acquaintance with the deceased), and fewer psychosocial resources (e.g., emotion regulation difficulties and lower social support). Further research that draws on pre-incident and longitudinal data will yield important insights into the processes that exacerbate or sustain post-incident psychological symptoms over time and provide important information for crisis preparedness and post-incident mental health interventions. © The Author(s) 2015.

Supercritical Regeneration of an Activated Carbon Fiber Exhausted with Phenol

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M. Jesus Sanchez-Montero

2018-01-01

Full Text Available The properties of supercritical CO2 (SCCO2 and supercritical water (SCW turn them into fluids with a great ability to remove organic adsorbates retained on solids. These properties were used herein to regenerate an activated carbon fiber (ACF saturated with a pollutant usually contained in wastewater and drinking water, phenol. Severe regeneration conditions, up to 225 bar and 400 °C, had to be employed in SCCO2 regeneration to break the strong interaction established between phenol and the ACF. Under suitable conditions (regeneration temperature, time, and pressure, and flow of SCCO2 the adsorption capacity of the exhausted ACF was completely recovered, and even slightly increased. Most of the retained phenol was removed by thermal desorption, but the extra percentage removed by extraction allowed SCCO2 regeneration to be significantly more efficient than the classical thermal regeneration methods. SCCO2 regeneration and SCW regeneration were also compared for the first time. The use of SCW slightly improved regeneration, although SCW pressure was thrice SCCO2 pressure. The pathways that controlled SCW regeneration were also investigated.

The influence of pressure ratio on the regenerator performance

Science.gov (United States)

Lin, Y.; Zhu, S.

2017-12-01

For a multi-stage pulse tube refrigerator with displacer, improving the regenerator efficiency is important. A displacer can get higher operating pressure ratio compared with inertance tube. The pressure ratio and porosity influence on the regenerator performance with is discussed, and CFD simulation is done on a two-stage pulse tube refrigerator with displacer to show that mass flow rate and pressure wave relation in the regenerator can be realized by a step-displacer.

Chapter 24: Electrical stimulation for improving nerve regeneration: where do we stand?

Science.gov (United States)

Gordon, Tessa; Sulaiman, Olewale A R; Ladak, Adil

2009-01-01

While injured neurons regenerate their axons in the peripheral nervous system, it is well recognized that functional recovery is frequently poor. Animal experiments in which injured motoneurons remain without peripheral targets (chronic axotomy) and Schwann cells in distal nerve stumps remain without innervation (chronic denervation) revealed that it is the duration of chronic axotomy and Schwann cell denervation that accounts for this poor functional recovery and not irreversible muscle atrophy that has been so commonly thought to be the reason. More recently, we demonstrated that axon outgrowth across lesion sites is a major contributing factor to the long delays incurred between the injury and the reinnervation of denervated targets. In the rat, a period of 1 month transpires before all motoneurons regenerate their axons across a lesion site. We have developed a technique of 1 h low-frequency electrical stimulation (ES) of the proximal nerve stump just after surgical repair of a transected peripheral nerve that greatly accelerates axon outgrowth. This technique has been applied in patients after carpal tunnel release surgery where the ES promoted the regeneration of all median nerves to reinnervate thenar muscles within 6-8 months, which contrasted with failure of any injured nerves to reinnervate muscles in the same time frame without ES. These findings are very promising such that the ES method could become a clinically viable tool for accelerating axon regeneration and muscle reinnervation.

Low intensity exercise training improves skeletal muscle regeneration potential

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Tiziana ePietrangelo

2015-12-01

Full Text Available Purpose: The aim of this study was to determine whether 12 days of low-to-moderate exercise training at low altitude (598 m a.s.l. improves skeletal muscle regeneration in sedentary adult women.Methods: Satellite cells were obtained from the vastus lateralis skeletal muscle of seven women before and after this exercise training at low altitude. They were investigated for differentiation aspects, superoxide anion production, antioxidant enzymes, mitochondrial potential variation after a depolarizing insult, intracellular Ca2+ concentrations, and micro (miRNA expression (miR-1, miR-133, miR-206.Results: In these myogenic populations of adult stem cells, those obtained after exercise training, showed increased Fusion Index and intracellular Ca2+ concentrations. This exercise training also generally reduced superoxide anion production in cells (by 12% to 67%, although not in two women, where there was an increase of ~15% along with a reduced superoxide dismutase activity. miRNA expression showed an exercise-induced epigenetic transcription profile that was specific according to the reduced or increased superoxide anion production of the cells. Conclusions: The present study shows that low-to-moderate exercise training at low altitude improves the regenerative capacity of skeletal muscle in adult women. The differentiation of cells was favored by increased intracellular calcium concentration and increased the fusion index. This low-to-moderate training at low altitude also depicted the epigenetic signature of cells.

Mass Shootings: The Role of the Media in Promoting Generalized Imitation.

Science.gov (United States)

Meindl, James N; Ivy, Jonathan W

2017-03-01

Mass shootings are a particular problem in the United States, with one mass shooting occurring approximately every 12.5 days. Recently a "contagion" effect has been suggested wherein the occurrence of one mass shooting increases the likelihood of another mass shooting occurring in the near future. Although contagion is a convenient metaphor used to describe the temporal spread of a behavior, it does not explain how the behavior spreads. Generalized imitation is proposed as a better model to explain how one person's behavior can influence another person to engage in similar behavior. Here we provide an overview of generalized imitation and discuss how the way in which the media report a mass shooting can increase the likelihood of another shooting event. Also, we propose media reporting guidelines to minimize imitation and further decrease the likelihood of a mass shooting.

Micromanaging cardiac regeneration : Targeted delivery of microRNAs for cardiac repair and regeneration

NARCIS (Netherlands)

Kamps, Jan A.A.M.; Krenning, Guido

2016-01-01

The loss of cardiomyocytes during injury and disease can result in heart failure and sudden death, while the adult heart has a limited capacity for endogenous regeneration and repair. Current stem cell-based regenerative medicine approaches modestly improve cardiomyocyte survival, but offer

Performance analysis and experimental study of heat-source tower solution regeneration

International Nuclear Information System (INIS)

Liang, Caihua; Wen, Xiantai; Liu, Chengxing; Zhang, Xiaosong

2014-01-01

Highlights: • Theoretical analysis is performed on the characteristics of heat-source tower. • Experimental study is performed on various rules of the solution regeneration rate. • The characteristics of solution regeneration vary widely with different demands. • Results are useful for optimizing the process of solution regeneration. - Abstract: By analyzing similarities and difference between the solution regeneration of a heat-source tower and desiccant solution regeneration, this paper points out that solution regeneration of a heat-source tower has the characteristics of small demands and that a regeneration rate is susceptible to outdoor ambient environments. A theoretical analysis is performed on the characteristics of a heat-source tower solution in different outdoor environments and different regeneration modes, and an experimental study is performed on variation rules of the solution regeneration rate of a cross-flow heat-source tower under different inlet parameters and operating parameters. The experimental results show that: in the operating regeneration mode, as the air volume was increased from 123 m 3 h −1 to 550 m 3 h −1 , the system heat transfer amount increased from 0.42 kW to 0.78 kW, and the regeneration rate increased from 0.03 g s −1 to 0.19 g s −1 . Increasing the solution flow may increase the system heat transfer amount; however, the regeneration rate decreased to a certain extent. In the regeneration mode when the system is idle, as the air volume was increased from 136 m 3 h −1 to 541 m 3 h −1 , the regeneration rate increased from 0.03 g s −1 to 0.1 g s −1 . The regeneration rate almost remained unchanged around 0.07 g s −1 as the solution flow is increased. In the regeneration mode with auxiliary heat when the system is idle, increasing the air volume and increasing the solution flow required more auxiliary heat, thereby improving the solution regeneration rate. As the auxiliary heat was increased from 0.33 k

Effect of different intervals of x-ray split doses on shoot production of in vitro derived explants of Gerbera jamesonii Bolus

Energy Technology Data Exchange (ETDEWEB)

Walther, F; Sauer, A [Federal Research Centre for Horticultural Plant Breeding, Ahrensburg (Germany)

1990-01-01

Full text: Linearity between rising x-ray doses and mutation rate is limited by the simultaneously increasing radiation damage; induced chromosome aberrations eliminate valuable factor mutations. The application of fractionated doses provides the opportunity for repair of a distinct portion of damage. The dose of 30 Gy was fractionated into two identical parts. The periods for repair were 0.5 to 48 hs. The absolute and cumulative number of post-irradiation regenerated axillary shoots on 4 subsequent dates of cutoff were used as parameters to estimate radiosensitivity. From an economical point of view the interval of 4 hs between two dose fractions may be recommended for practice. (author)

Improved bioactivity of selective laser melting titanium: Surface modification with micro-/nano-textured hierarchical topography and bone regeneration performance evaluation

Energy Technology Data Exchange (ETDEWEB)

Xu, Jia-yun [Department of Oral Implantology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055 (China); Chen, Xian-shuai; Zhang, Chun-yu [Guangzhou Institute of Advanced Technology, Chinese Academy of Science, Guangzhou 511458 (China); Liu, Yun; Wang, Jing [Department of Oral Implantology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055 (China); Deng, Fei-long, E-mail: drdfl@163.com [Department of Oral Implantology, Guanghua School of Stomatology, Hospital of Stomatology, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Stomatology, Guangzhou 510055 (China)

2016-11-01

Selective laser melting (SLM) titanium requires surface modification to improve its bioactivity. The microrough surface of it can be utilized as the micro primary substrate to create a micro-/nano-textured topography for improved bone regeneration. In this study, the microrough SLM titanium substrate was optimized by sandblasting, and nano-porous features of orderly arranged nanotubes and disorderly arranged nanonet were produced by anodization (SAN) and alkali-heat treatment (SAH), respectively. The results were compared with the control group of an untreated surface (native-SLM) and a microtopography only surface treated by acid etching (SLA). The effects of the different topographies on cell functions and bone formation performance were evaluated in vitro and in vivo. It was found that micro-/nano-textured topographies of SAN and SAH showed enhanced cell behaviour relative to the microtopography of SLA with significantly higher proliferation on the 1st, 3rd, 5th and 7th day (P < 0.05) and higher total protein contents on the 14th day (P < 0.05). In vivo, SAN and SAH formed more successively regenerated bone, which resulted in higher bone-implant contact (BIC%) and bone-bonding force than native-SLM and SLA. In addition, the three-dimensional nanonet of SAH was expected to be more similar to native extracellular matrix (ECM) and thus led to better bone formation. The alkaline phosphatase activity of SAH was significantly higher than the other three groups at an earlier stage of the 7th day (P < 0.05) and the BIC% was nearly double that of native-SLM and SLA in the 8th week. In conclusion, the addition of nano-porous features on the microrough SLM titanium surface is effective in improving the bioactivity and bone regeneration performance, in which the ECM-like nanonet with a disorderly arranged biomimetic feature is suggested to be more efficient than nanotubes. - Highlights: • SLM titanium is modified by adding nano-porous features to the microrough substrate

Improved bioactivity of selective laser melting titanium: Surface modification with micro-/nano-textured hierarchical topography and bone regeneration performance evaluation

International Nuclear Information System (INIS)

Xu, Jia-yun; Chen, Xian-shuai; Zhang, Chun-yu; Liu, Yun; Wang, Jing; Deng, Fei-long

2016-01-01

Selective laser melting (SLM) titanium requires surface modification to improve its bioactivity. The microrough surface of it can be utilized as the micro primary substrate to create a micro-/nano-textured topography for improved bone regeneration. In this study, the microrough SLM titanium substrate was optimized by sandblasting, and nano-porous features of orderly arranged nanotubes and disorderly arranged nanonet were produced by anodization (SAN) and alkali-heat treatment (SAH), respectively. The results were compared with the control group of an untreated surface (native-SLM) and a microtopography only surface treated by acid etching (SLA). The effects of the different topographies on cell functions and bone formation performance were evaluated in vitro and in vivo. It was found that micro-/nano-textured topographies of SAN and SAH showed enhanced cell behaviour relative to the microtopography of SLA with significantly higher proliferation on the 1st, 3rd, 5th and 7th day (P < 0.05) and higher total protein contents on the 14th day (P < 0.05). In vivo, SAN and SAH formed more successively regenerated bone, which resulted in higher bone-implant contact (BIC%) and bone-bonding force than native-SLM and SLA. In addition, the three-dimensional nanonet of SAH was expected to be more similar to native extracellular matrix (ECM) and thus led to better bone formation. The alkaline phosphatase activity of SAH was significantly higher than the other three groups at an earlier stage of the 7th day (P < 0.05) and the BIC% was nearly double that of native-SLM and SLA in the 8th week. In conclusion, the addition of nano-porous features on the microrough SLM titanium surface is effective in improving the bioactivity and bone regeneration performance, in which the ECM-like nanonet with a disorderly arranged biomimetic feature is suggested to be more efficient than nanotubes. - Highlights: • SLM titanium is modified by adding nano-porous features to the microrough substrate

Effects of calcium gluconate and ascorbic acid on controlling shoot ...

African Journals Online (AJOL)

In vitro shoot necrosis is a quite widespread disorder affecting raspberry micropropagation. This study was conducted to investigate effects of calcium gluconate and ascorbic acid on shoot necrosis and dieback of raspberry shoots during micropropagation. Nodal segments of primocane-fruiting raspberry cultivars 'Allgold', ...

Tragedy and the Meaning of School Shootings

Science.gov (United States)

Warnick, Bryan R.; Johnson, Benjamin A.; Rocha, Samuel

2010-01-01

School shootings are traumatic events that cause a community to question itself, its values, and its educational systems. In this article Bryan Warnick, Benjamin Johnson, and Samuel Rocha explore the meanings of school shootings by examining three recent books on school violence. Topics that grow out of these books include (1) how school shootings…

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)

Distributed trouble-shooting

NARCIS (Netherlands)

Post, W.M.; Bogaard, S.A.A. van den; Rasker, P.C.

2004-01-01

When knowledge, required for trouble-shooting at sea, can be supplied real-time but from a distance, problems, such as with the limited availability of specialists, and the high costs of maintenance, may be tackled. Unclear is, however, how this redistribution of knowledge will work in practice. We

Firearm Legislation and Fatal Police Shootings in the United States.

Science.gov (United States)

Kivisto, Aaron J; Ray, Bradley; Phalen, Peter L

2017-07-01

To examine whether stricter firearm legislation is associated with rates of fatal police shootings. We used a cross-sectional, state-level design to evaluate the effect of state-level firearm legislation on rates of fatal police shootings from January 1, 2015, through October 31, 2016. We measured state-level variation in firearm laws with legislative scorecards from the Brady Center, and for fatal police shootings we used The Counted, an online database maintained by The Guardian. State-level firearm legislation was significantly associated with lower rates of fatal police shootings (incidence rate ratio = 0.961; 95% confidence interval = 0.939, 0.984). When we controlled for sociodemographic factors, states in the top quartile of legislative strength had a 51% lower incidence rate than did states in the lowest quartile. Laws aimed at strengthening background checks, promoting safe storage, and reducing gun trafficking were associated with fewer fatal police shootings. Legislative restrictions on firearms are associated with reductions in fatal police shootings. Public Health Implications. Although further research is necessary to determine causality and potential mechanisms, firearm legislation is a potential policy solution for reducing fatal police shootings in the United States.

The correlation of the radiocaesium concentration of new shoots harvested in 2012 and old leaves, and new shoots harvested in 2011 grown in Kanagawa prefecture

International Nuclear Information System (INIS)

Shiraki, Yoshiya; Takeda, Hajime; Okamoto, Tamotsu; Kita, Nobuhiro

2013-01-01

We conducted this study to analyze the correlation between 137 Cs concentration of new shoots harvested in the first crop of tea in 2012, and new shoots harvested in the shuto-bancha in 2011 and old leaves harvested at the same time respectively. In the first crop of tea in 2012, the 137 Cs concentration of new shoots was related to that of old leaves, and the correlation of the coefficient was 0.663(p 137 Cs concentration(new shoots/old leaves) was related to the days until harvest of the first crop of tea in 2012, and the correlation coefficient was -0.771(p 137 Cs concentration was derived from the dilution effect due to growth and development of tea plants. Regression analysis was performed to forecast the 137 Cs concentration of the new shoots in the first crop of tea. The 137 Cs concentration of new shoots in the harvested first crop of tea(Y) was related to the 137 Cs concentration of old leaves harvested the previous winter(X). The correlation of the coefficient was 0.783(p 137 Cs concentration of new shoots of the first crop of tea in 2012 decreased about 1/6 to 1/25 compared with that of new shoots of the first crop of tea in 2011. (author)

Exogenous Supplementation of Silicon Improved the Recovery of Hyperhydric Shoots in Dianthus caryophyllus L. by Stabilizing the Physiology and Protein Expression

Science.gov (United States)

Soundararajan, Prabhakaran; Manivannan, Abinaya; Cho, Yoon S.; Jeong, Byoung R.

2017-01-01

Hyperhydricity is one of the major problems hindering in vitro propagation of Dianthus caryophyllus L. Silicon (Si) is a well-known beneficial element renowned for its stress amelioration properties in plants. This study has demonstrated the physiological and molecular mechanism behind the Si-mediated recovery from hyperhydricity in D. caryophyllus L. ‘Green Beauty’. Four weeks old hyperhydric shoots obtained from temporary immersion system were cultured on the Murashige and Skoog medium supplemented with 0 (control), 1.8 mM, or 3.6 mM of potassium silicate (K2SiO3). After 2 weeks of culture, we observed only 20% of hyperhydric shoots were recovered in control. On the other hand hyperhydricity, shoot recovery percentage in 1.8 mM and 3.6 mM of Si were 44% and 36%, respectively. Shoots in control possessed higher lipid peroxidation rate compared to the Si treatments. Similarly, damaged stomata were detected in the control, while Si treatments restored the normal stomatal development. Expressions of superoxide dismutase, guaiacol peroxidase, and catalase varied between the control and Si treatments. Furthermore, a proteomic analysis showed that as compared with the control Si up-regulated 17 and 10 protein spots in abundance at 1.8 and 3.6 mM of Si, respectively. In comparison to the 3.6 mM, 1.8 mM of Si treatment up-regulated 19 proteins and down-regulated 7 proteins. Identified proteins were categorized into six groups according to their biological roles such as ribosomal binding, oxido-reduction, hormone/cell signaling, metal/ion binding, defense, and photosynthesis. The proteomic results revealed that Si actively involved in the various metabolisms to accelerate the recovery of the shoots from hyperhydricity. Thus, the outcomes of this study can be utilized for addressing the molecular insight of hyperhydricity and its recovery mechanism by the supplementation of Si. Therefore, we conclude that active involvement of Si in the regulation and signaling process

In vitro propagation of peanut (Arachis hypogaea L.) by shoot tip culture.

Science.gov (United States)

Ozudogru, Elif Aylin; Kaya, Ergun; Lambardi, Maurizio

2013-01-01

Peanut (Arachis hypogaea L.), also known as groundnut, is the most important species of Arachis genus, originating from Brazil and Peru. Peanut seeds contain high seed oil, proteins, amino acids, and vitamin E, and are consumed worldwide as edible nut, peanut butter, or candy, and peanut oil extracted from the seeds. The meal remaining after oil extraction is also used for animal feed. However, its narrow germplasm base, together with susceptibility to diseases, pathogens, and weeds, decreases yield and seed quality and causes great economic losses annually. Hence, the optimization of efficient in vitro propagation procedures would be highly effective for peanut propagation, as it would raise yield and improve seed quality and flavor. Earlier reports on traditional micropropagation methods, based on axillary bud proliferation which guarantees the multiplication of true-to-type plants, are still limited. This chapter describes a micropropagation protocol to improve multiple shoot formation from shoot-tip explants by using AgNO(3) in combination with plant growth regulators.

The Level of Vision Necessary for Competitive Performance in Rifle Shooting: Setting the Standards for Paralympic Shooting with Vision Impairment

NARCIS (Netherlands)

Allen, P.M.; Latham, K.; Mann, D.L.; Ravensbergen, H.J.C.; Myint, J.

2016-01-01

The aim of this study was to investigate the level of vision impairment (VI) that would reduce performance in shooting; to guide development of entry criteria to visually impaired (VI) shooting. Nineteen international-level shooters without VI took part in the study. Participants shot an air rifle,

An improved micropropagation of Arnebia hispidissima (Lehm.) DC. and assessment of genetic fidelity of micropropagated plants using DNA-based molecular markers.

Science.gov (United States)

Phulwaria, Mahendra; Rai, Manoj K; Shekhawat, N S

2013-07-01

An efficient and improved in vitro propagation method has been developed for Arnebia hispidissima, a medicinally and pharmaceutically important plant species of arid and semiarid regions. Nodal segments (3-4 cm) with two to three nodes obtained from field grown plants were used as explants for shoot proliferation. Murashige and Skoog's (MS) medium supplemented with cytokinins with or without indole-3-acetic acid (IAA) or naphthalene acetic acid was used for shoot multiplication. Out of different PGRs combinations, MS medium containing 0.5 mg l(-1) 6-benzylaminopurine and 0.1 mg l(-1) IAA was optimal for shoot multiplication. On this medium, explants produced the highest number of shoots (47.50 ± 0.38). About 90 % of shoots rooted ex vitro on sterile soilrite under the greenhouse condition when the base (2-4 mm) of shoots was treated with 300 mg l(-1) of indole-3-butyric acid for 5 min. The plantlets were hardened successfully in the greenhouse with 85-90 % survival rate. Random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers were employed to assess the genetic stability of in vitro-regenerated plants of A. hispidissima. Out of 40 (25 RAPD and 15 ISSR) primers screened, 15 RAPD and 7 ISSR primers produced a total number of 111 (77 RAPD and 34 ISSR) reproducible amplicons. The amplified products were monomorphic across all the micropropagated plants and were similar to the mother plant. To the best of our knowledge, it is the first report on the assessment of the genetic fidelity in micropropagated plants of A. hispidissima.

Carnation (Dianthus caryophylus L.).

Science.gov (United States)

Nontaswatsri, Chalermsri; Fukai, Seiichi

2006-01-01

Carnation is a valuable crop for the cut flower industry and demand for new and improved varieties is growing. However, genetic transformation of carnations is currently limited because of a lack of efficient routine technique. In this chapter, we present an easy and effective protocol for gene transfer to carnation node explants and subsequent adventitious shoot regeneration. For high-adventitious shoot regeneration, node explants from first to third node of 5- to 8-cm long shoots were cultured on Murashige and Skoog (MS) medium, containing 1.0 mg/Lthidiazuron (TDZ), 0.1 mg/L alpha-napthalenoacetic acid (NAA), 20 g/L sucrose, and 2 g/L Gellan gum for 10 d. Then the explants were cut into 8 radial segments and subcultured onto MS medium, containing 1.0 mg/L BA, 0.1 mg/L NAA, 20 g/L sucrose and 2 g/L Gellan Gum. For effective genetic transformation, 3- to 5-d precultured node explants were submerged in an Agrobacerium suspension for 10 min, then cocultivated on filter paper soaked with water and 50 microM acetosyringone (AS). After cocultivation, the explants were cut into eight radial segments and subcultured onto selection medium until transformed shoots regenerated from the explants.

Enhanced plant regeneration in lemna minor by amino acids

International Nuclear Information System (INIS)

Yang, L.; Han, H.; Zhou, K.; Ren, C.; Zhu, Y.

2014-01-01

In present study we investigated the effects of different L-amino acids on the plant regeneration from callus of Lemna minor, and established an efficient protocol. Among the 20 L-amino acids, only L-Ser and L-Gly showed significant improving effect, with the optimal concentration being 1 mM and 1.5 mM, respectively. A regeneration frequency of 46% was observed when the callus transferred to the regeneration medium with addition of 1 mM L-Ser for 11 days. After 26 days of cultivation, the frond regeneration achieved 100% and 94% for 1 mM L-Ser and 1.5 mM L-Gly treatment, respectively. (author)

Optimisation of tomato Micro-tom regeneration and selection on glufosinate/Basta and dependency of gene silencing on transgene copy number.

Science.gov (United States)

Khuong, Thi Thu Huong; Crété, Patrice; Robaglia, Christophe; Caffarri, Stefano

2013-09-01

An efficient protocol of transformation and selection of transgenic lines of Micro-tom, a widespread model cultivar for tomato, is reported. RNA interference silencing efficiency and stability have been investigated and correlated with the number of insertions. Given its small size and ease of cultivation, the tomato (Solanum lycopersicon) cultivar Micro-tom is of widespread use as a model tomato plant. To create and screen transgenic plants, different selectable markers are commonly used. The bar marker carrying the resistance to the herbicide glufosinate/Basta, has many advantages, but it has been little utilised and with low efficiency for identification of tomato transgenic plants. Here we describe a procedure for accurate selection of transgenic Micro-tom both in vitro and in soil. Immunoblot, Southern blot and phenotypic analyses showed that 100 % of herbicide-resistant plants were transgenic. In addition, regeneration improvement has been obtained by using 2 mg/l Gibberellic acid in the shoot elongation medium; rooting optimisation on medium containing 1 mg/l IAA allowed up to 97 % of shoots developing strong and very healthy roots after only 10 days. Stable transformation frequency by infection of leaf explants with Agrobacterium reached 12 %. Shoots have been induced by combination of 1 mg/l zeatin-trans and 0.1 mg/l IAA. Somatic embryogenesis of cotyledon on medium containing 1 mg/l zeatin + 2 mg/l IAA is described in Micro-tom. The photosynthetic psbS gene has been used as reporter gene for RNA silencing studies. The efficiency of gene silencing has been found equivalent using three different target gene fragments of 519, 398 and 328 bp. Interestingly, silencing efficiency decreased from T0 to the T3 generation in plants containing multiple copies of the inserted T-DNA, while it was stable in plants containing a single insertion.

Ferns: the missing link in shoot evolution and development

Directory of Open Access Journals (Sweden)

Andrew Robert George Plackett

2015-11-01

Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

Static and dynamic biomechanical properties of the regenerating rabbit Achilles tendon.

Science.gov (United States)

Nagasawa, Koji; Noguchi, Masahiko; Ikoma, Kazuya; Kubo, Toshikazu

2008-07-01

Since tendons show viscoelastic behavior, dynamic viscoelastic properties should be assessed in addition to static biomechanical properties. We evaluated differences between static and dynamic biomechanical properties of the regenerating rabbit Achilles tendon following tenotomy. At 3, 6, or 12 weeks after right Achilles tenotomy, the right (regenerating) and left (control) tendons were collected with the calcaneus from 49 rabbits. A unidirectional failure test and a dynamic viscoelastic test were conducted. Tensile strength and Young's modulus (static biomechanical properties) in the regenerating group at Week 6 were significantly greater than at Week 3, while at Week 12, these were significantly greater than at Week 6. However, even at Week 12, both parameters were less than in the control group. The value of tan delta represents dynamic viscoelasticity, a smaller tan delta indicates greater elasticity. tan delta for the regenerating group was significantly greater than for the control group at Week 3, but regenerating and control groups did not significantly differ at Week 6. No marked change was seen from Weeks 6 to 12 in the regenerating group, and no significant difference in tan delta was evident between the regenerating and control groups at Week 12. Dynamic biomechanical properties of regenerating rabbit Achilles tendons may improve more rapidly than static biomechanical properties. Ability to tolerate dynamic movement in the healing Achilles tendon may improve more rapidly than ability to withstand static stresses.

Resynthesized Brassica juncea lines with novel organellar genome ...

Indian Academy of Sciences (India)

To obtain shoot cultures, shoot apices were ... and culture, plant regeneration and hardening etc. are as described ... Hence two other media were tested for plant regeneration. .... genomes exert a strong influence on reorganization of nuclear.

Mental illness, mass shootings, and the politics of American firearms.

Science.gov (United States)

Metzl, Jonathan M; MacLeish, Kenneth T

2015-02-01

Four assumptions frequently arise in the aftermath of mass shootings in the United States: (1) that mental illness causes gun violence, (2) that psychiatric diagnosis can predict gun crime, (3) that shootings represent the deranged acts of mentally ill loners, and (4) that gun control "won't prevent" another Newtown (Connecticut school mass shooting). Each of these statements is certainly true in particular instances. Yet, as we show, notions of mental illness that emerge in relation to mass shootings frequently reflect larger cultural stereotypes and anxieties about matters such as race/ethnicity, social class, and politics. These issues become obscured when mass shootings come to stand in for all gun crime, and when "mentally ill" ceases to be a medical designation and becomes a sign of violent threat.

Genetic improvement of the shoot architecture and yield in soya bean plants via the manipulation of GmmiR156b.

Science.gov (United States)

Sun, Zhengxi; Su, Chao; Yun, Jinxia; Jiang, Qiong; Wang, Lixiang; Wang, Youning; Cao, Dong; Zhao, Fang; Zhao, Qingsong; Zhang, Mengchen; Zhou, Bin; Zhang, Lei; Kong, Fanjiang; Liu, Baohui; Tong, Yiping; Li, Xia

2018-05-05

The optimization of plant architecture in order to breed high-yielding soya bean cultivars is a goal of researchers. Tall plants bearing many long branches are desired, but only modest success in reaching these goals has been achieved. MicroRNA156 (miR156)-SQUAMOSA PROMOTER BINDING PROTEIN-LIKE (SPL) gene modules play pivotal roles in controlling shoot architecture and other traits in crops like rice and wheat. However, the effects of miR156-SPL modules on soya bean architecture and yield, and the molecular mechanisms underlying these effects, remain largely unknown. In this study, we achieved substantial improvements in soya bean architecture and yield by overexpressing GmmiR156b. Transgenic plants produced significantly increased numbers of long branches, nodes and pods, and they exhibited an increased 100-seed weight, resulting in a 46%-63% increase in yield per plant. Intriguingly, GmmiR156b overexpression had no significant impact on plant height in a growth room or under field conditions; however, it increased stem thickness significantly. Our data indicate that GmmiR156b modulates these traits mainly via the direct cleavage of SPL transcripts. Moreover, we found that GmSPL9d is expressed in the shoot apical meristem and axillary meristems (AMs) of soya bean, and that GmSPL9d may regulate axillary bud formation and branching by physically interacting with the homeobox gene WUSCHEL (WUS), a central regulator of AM formation. Together, our results identify GmmiR156b as a promising target for the improvement of soya bean plant architecture and yields, and they reveal a new and conserved regulatory cascade involving miR156-SPL-WUS that will help researchers decipher the genetic basis of plant architecture. © 2018 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.

Rapid multiplication of Dalbergia sissoo Roxb.: a timber yielding tree legume through axillary shoot proliferation and ex vitro rooting.

Science.gov (United States)

Vibha, J B; Shekhawat, N S; Mehandru, Pooja; Dinesh, Rachana

2014-01-01

An efficient and improved method for in vitro propagation of mature tree of Dalbergia sissoo, an ecologically and commercially important timber yielding species, has been developed through axillary shoot proliferation. Bud breaking occurred from nodal shoot segments derived from rejuvenated shoots produced during early spring from a 20-25-year-old lopped tree, on MS medium containing 8.88 μM benzylaminopurine (BAP). Multiple shoots differentiated (20-21shoots/node) on re-culture of explants on half-strength agar gelled amended MS medium with a combination of 2.22 μM of BAP and 0.002 μM of thidiazuron (TDZ) with 1.0 mM each of Ca(NO3)2, K2SO4, KCl, and NH4(SO4)2. The maximum shoot multiplication (29-30 shoots/node) was achieved on subculturing in the above mentioned but liquid medium. Furthermore, the problem of shoot tip necrosis and defoliation observed on solid medium were overcome by the use of liquid medium. Ex vitro rooting was achieved on soilrite after basal treatment of microshoots with 984 μM of indole-3-butyric acid (IBA) for 2 min. About 90 % microshoots were rooted on soilrite within 2-3 weeks under the greenhouse conditions. From 20 nodal shoot segments, about 435 hardened plants were acclimatized and transplanted. This is the first report for rapid in vitro propagation of mature trees of D. sissoo on liquid medium followed by ex vitro rooting.

G-CSF prevents caspase 3 activation in Schwann cells after sciatic nerve transection, but does not improve nerve regeneration.

Science.gov (United States)

Frost, Hanna K; Kodama, Akira; Ekström, Per; Dahlin, Lars B

2016-10-15

Exogenous granulocyte-colony stimulating factor (G-CSF) has emerged as a drug candidate for improving the outcome after peripheral nerve injuries. We raised the question if exogenous G-CSF can improve nerve regeneration following a clinically relevant model - nerve transection and repair - in healthy and diabetic rats. In short-term experiments, distance of axonal regeneration and extent of injury-induced Schwann cell death was quantified by staining for neurofilaments and cleaved caspase 3, respectively, seven days after repair. There was no difference in axonal outgrowth between G-CSF-treated and non-treated rats, regardless if healthy Wistar or diabetic Goto-Kakizaki (GK) rats were examined. However, G-CSF treatment caused a significant 13% decrease of cleaved caspase 3-positive Schwann cells at the lesion site in healthy rats, but only a trend in diabetic rats. In the distal nerve segments of healthy rats a similar trend was observed. In long-term experiments of healthy rats, regeneration outcome was evaluated at 90days after repair by presence of neurofilaments, wet weight of gastrocnemius muscle, and perception of touch (von Frey monofilament testing weekly). The presence of neurofilaments distal to the suture line was similar in G-CSF-treated and non-treated rats. The weight ratio of ipsi-over contralateral gastrocnemius muscles, and perception of touch at any time point, were likewise not affected by G-CSF treatment. In addition, the inflammatory response in short- and long-term experiments was studied by analyzing ED1 stainable macrophages in healthy rats, but in neither case was any attenuation seen at the injury site or distal to it. G-CSF can prevent caspase 3 activation in Schwann cells in the short-term, but does not detectably affect the inflammatory response, nor improve early or late axonal outgrowth or functional recovery. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Multiple vantage points on the mental health effects of mass shootings.

Science.gov (United States)

Shultz, James M; Thoresen, Siri; Flynn, Brian W; Muschert, Glenn W; Shaw, Jon A; Espinel, Zelde; Walter, Frank G; Gaither, Joshua B; Garcia-Barcena, Yanira; O'Keefe, Kaitlin; Cohen, Alyssa M

2014-09-01

The phenomenon of mass shootings has emerged over the past 50 years. A high proportion of rampage shootings have occurred in the United States, and secondarily, in European nations with otherwise low firearm homicide rates; yet, paradoxically, shooting massacres are not prominent in the Latin American nations with the highest firearm homicide rates in the world. A review of the scientific literature from 2010 to early 2014 reveals that, at the individual level, mental health effects include psychological distress and clinically significant elevations in posttraumatic stress, depression, and anxiety symptoms in relation to the degree of physical exposure and social proximity to the shooting incident. Psychological repercussions extend to the surrounding affected community. In the aftermath of the deadliest mass shooting on record, Norway has been in the vanguard of intervention research focusing on rapid delivery of psychological support and services to survivors of the "Oslo Terror." Grounded on a detailed review of the clinical literature on the mental health effects of mass shootings, this paper also incorporates wide-ranging co-author expertise to delineate: 1) the patterning of mass shootings within the international context of firearm homicides, 2) the effects of shooting rampages on children and adolescents, 3) the psychological effects for wounded victims and the emergency healthcare personnel who care for them, 4) the disaster behavioral health considerations for preparedness and response, and 5) the media "framing" of mass shooting incidents in relation to the portrayal of mental health themes.

CO2 regeneration performance enhancement by nanoabsorbents for energy conversion application

International Nuclear Information System (INIS)

Lee, Jung Hun; Lee, Jae Won; Kang, Yong Tae

2016-01-01

Graphical abstract: (a) Optical profiling image of the surface of copper after regeneration process in nanoabsorbents, Al 2 O 3 (45 nm, 0.01 vol%). (b) The number of regeneration sites by the nanoabsorbents. - Highlights: • CO 2 regeneration performance is enhanced by using Al 2 O 3 nanoabsorbents. • CO 2 regeneration process on the heating surface is visualized in nanoabsorbents. • Surface modification by nanoabsorbents has a greater effect than the nanoparticle size. • The mechanism of surface effect is the most plausible to explain the regeneration performance enhancement. - Abstract: Due to the recent increase in the consumption of energy and the use of fossil fuels, global warming has become a serious issue. To address this problem, CO 2 gas, which is the major element of the greenhouse gases, should be captured, regenerated and converted to useful fuels. The Integrated Gasification Combined Cycle (IGCC) and cement process generate large amount of CO 2 , which are controlled through pre-combustion capture. However, this method has a disadvantage because the system temperature should be decreased to −20 °C or lower. Therefore, the development of new absorbent is required to reduce the energy consumed for refrigeration. There is a study that improved the CO 2 absorption performance by adding Al 2 O 3 nanoparticles to methanol. However, studies on the regeneration of CO 2 in nanofluid absorbents (nanoabsorbents) are insufficient. Therefore, in this study, the CO 2 regeneration performance in Al 2 O 3 nanoabsorbents is evaluated. It is found that the regeneration performance of CO 2 is improved by 16% by using nanoabsorbents compared to methanol. Furthermore, the CO 2 regeneration characteristics of nanoabsorbents are analyzed by considering the detachment time of CO 2 bubbles from the surface, the cross-sectional area of CO 2 bubble, and the number of regeneration sites through the CO 2 regeneration and bubble visualization experiments. It is concluded

An Improved Micropropagation Protocol by Ex Vitro Rooting of Passiflora edulis Sims. f. flavicarpa Deg. through Nodal Segment Culture.

Science.gov (United States)

Shekhawat, Mahipal S; Manokari, M; Ravindran, C P

2015-01-01

A procedure for rapid clonal propagation of Passiflora edulis Sims. f. flavicarpa Deg. (Passifloraceae) has been developed in this study. Nodal explants were sterilized with 0.1% HgCl2 and inoculated on Murashige and Skoog (MS) basal medium. The addition of 2.0 mgL(-1) 6-benzylaminopurine (BAP) to MS medium caused an extensive proliferation of multiple shoots (8.21 ± 1.13) primordial from the nodal meristems. Subculturing of these multiple shoots on the MS medium augmented with 1.0 mgL(-1) of each BAP and Kinetin (Kin) was successful for the multiplication of the shoots in vitro with maximum numbers of shoots (25.73 ± 0.06) within four weeks of incubation. Shoots were rooted best (7.13 ± 0.56 roots/shoots) on half strength MS medium supplemented with 2.0 mgL(-1) indole-3 butyric acid (IBA). All in vitro regenerated shoots were rooted by ex vitro method, and this has achieved 6-7 roots per shoot by pulsing of cut ends of the shoots using 200 as well as 300 mgL(-1) IBA. The plantlets were hardened in the greenhouse for 4-5 weeks. The hardened plantlets were shifted to manure containing nursery polybags after five weeks and then transferred to a sand bed for another four weeks for acclimatization before field planting with 88% survival rate.

Human amniotic mesenchymal stromal cell transplantation improves endometrial regeneration in rodent models of intrauterine adhesions.

Science.gov (United States)

Gan, Lu; Duan, Hua; Xu, Qian; Tang, Yi-Qun; Li, Jin-Jiao; Sun, Fu-Qing; Wang, Sha

2017-05-01

Intrauterine adhesion (IUA) is a common uterine cavity disease characterized by the unsatisfactory regeneration of damaged endometria. Recently, stem cell transplantation has been proposed to promote the recovery process. Here we investigated whether human amniotic mesenchymal stromal cells (hAMSCs), a valuable resource for transplantation therapy, could improve endometrial regeneration in rodent IUA models. Forty female Sprague-Dawley rats were randomly assigned to five groups: normal, sham-operated, mechanical injury, hAMSC transplantation, and negative control group. One week after intervention and transplantation, histological analyses were performed, and immunofluorescent and immunohistochemical expression of cell-specific markers and messenger RNA expression of cytokines were measured. Thicker endometria, increased gland numbers and fewer fibrotic areas were found in the hAMSC transplantation group compared with the mechanical injury group. Engraftment of hAMSCs was detected by the presence of anti-human nuclear antigen-positive cells in the endometrial glands of the transplantation uteri. Transplantation of hAMSCs significantly decreased messenger RNA levels of pro-inflammatory cytokines (tumor necrosis factor-α and interleukin-1β), and increased those of anti-inflammatory cytokines (basic fibroblast growth factor, and interleukin-6) compared with the injured uterine horns. Immunohistochemical expression of endometrial epithelial cells was revealed in specimens after hAMSC transplantation, whereas it was absent in the mechanically injured uteri. hAMSC transplantation promotes endometrial regeneration after injury in IUA rat models, possibly due to immunomodulatory properties. These cells provide a more easily accessible source of stem cells for future research into the impact of cell transplantation on damaged endometria. Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

A novel energy regeneration system for emulsion pump tests

Energy Technology Data Exchange (ETDEWEB)

Yilei, Li; Zhencai, Zhu; Guohua, Cao [China University of Mining and Technology, Xuzhou (China); Guoan, Chen [Command Academy of the Corps of Engineers, Xuzhou (China)

2013-04-15

A novel energy regeneration system based on cylinders and a rectifier valve for emulsion pump tests is presented and studied. The overall structure and working principles of this system are introduced. Both simulation and experiments are carried out to investigate the energy regeneration feasibility and capability of this novel system. The simulation and experimental results validate that this system is able to save energy and satisfy the test requirement. The energy recovery coefficient and overall energy regeneration coefficient of the test bench are 0.785 and 0.214, respectively. Measures to improve these two coefficients are also given accordingly after analysis of power loss. This novel system brings a new method of energy regeneration for emulsion pump tests.

Shoot Differentiation in Callus Cultures of Datura Innoxia

DEFF Research Database (Denmark)

Engvild, Kjeld Christensen

1973-01-01

promoted shoot differentiation. Gibberellic acid inhibited shoot formation weakly, but inhibited proper leaf blade formation. Root differentiation was rare. The callus cultures of Datura innoxia grew rapidly (100-fold in 4 weeks) on a slightly modified Murashige and Skoog medium (0.5 mg/l thiamin · HCl, p...

Handgun Acquisitions in California After Two Mass Shootings.