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Öğe Applications of carbon nanomaterials in the plant system: A perspective view on the pros and cons(Elsevier, 2019) Verma, Sandeep Kumar; Das, Ashok Kumar; Gantait, Saikat; Kumar, Vinay; Gürel, EkremWith the remarkable development in the field of nanotechnology, carbon-based nanomaterials (CNMs) have been widely used for numerous applications in different areas of the plant system. The current understanding about the CNMs' accumulation, translocation, plant growth responses, and stress modulations in the plant system is far from complete. There have been relentless efforts by the researchers worldwide in order to acquire newer insights into the plant-CNMs interactions and the consequences. The present review intends to update the reader with the status of the impacts of the different CNMs on plant growth. Research reports from the plant biotechnologists have documented mixed effects (which are dependent on CNMs' concentration) of the CNMs' exposure on plants ranging from enhanced crop yield to acute cytotoxicity. The growth and yield pattern vary from species to species and are dependent on the dosage of the CNMs applied. Studies found an increase in vegetative growth and yield of fruit/seed at lower concentration of CNMs, but a decrease in these observables were also noted when higher concentrations of CNMs were used. In general, at lower concentrations, CNMs were found to be effective in enhancing (water uptake, water transport, seed germination, nitrogenase, photosystemand antioxidant activities), activating (water channels proteins) and promoting (nutrition absorption); all these change when concentrations are raised. All these aspects have been reviewed thoroughly in this article, with a focus on the recent updates on the role of the CNMs in augmenting or retarding plant growth. Sections have been devoted to the various features of the CNMs and their roles in inducing plant growth, phytotoxic responses of the plants and overall crop improvement. Concluding remarks have been added to propose future directions of research on the CNMs-plant interactions and also to sound a warning on the use of CNMs in agriculture. (C) 2019 Elsevier B.V. All rights reserved.Öğe Calcium and magnesium elimination enhances accumulation of cardenolides in callus cultures of endemic Digitalis species of Turkey(Elsevier France-Editions Scientifiques Medicales Elsevier, 2013) Şahin, Günce; Verma, Sandeep Kumar; Gürel, EkremElimination of calcium (Ca), magnesium (Mg) or both from the medium of callus cultures of Digitalis davisiana Heywood, Digitalis lamarckii Ivanina, Digitalis trojana Ivanina and Digitalis cariensis Boiss. ex Jaub. et Spach increased cardenolides production. Callus was induced from hypocotyl segments from one-month old seedlings were cultured on MS medium containing 0.5 mu g ml(-1) thidiazuron (TDZ) and 0.25 mu g ml(-1) indole acetic acid (IAA). After 30 days of culture, callus was transferred in hormone-free MS medium (MSO) as well as Ca or Mg or both were completely eliminated from same medium. The amount of five cardenolides from D. davisiana Heywood, D. lamarckii Ivanina, D. trojana Ivanina and D. cariensis Boiss. ex Jaub. et Spach were compared. Higher amounts of five cardenolides and total cardenolides were obtained when callus of four Digitalis species were incubated on MS medium lacking both Ca and Mg. The mean contents of total cardenolides obtained were in the order of D. lamarckii (2017.97 mu g g(-1)) > D. trojana (1385.75 mu g g(-1)) > D. cariensis (1038.65 mu g g(-1)) > D. davisiana (899.86 mu g g(-1)) when both Ca and Mg were eliminated from the medium, respectively. This protocol is useful for development of new strategies for the large-scale production of cardenolides. 2013 Elsevier Masson SAS. All rights reserved.Öğe Direct shoot regeneration from leaf explants of Digitalis Lamarckii, an endemic medicinal species(2011) Verma, Sandeep Kumar; Yücesan, Bahtiyar Buhara; Şahin, Günce; Gürel, Songül; Gürel, EkremThis study reports, for the first time, an efficient in vitro plant regeneration protocol for Digitalis lamarckii Ivan. (dwarf foxglove) via direct shoot organogenesis. Two sets of experiments were carried out; the first compared diff erent concentrations of 6-benzylaminopurine (BAP), kinetin, thidiazuron (TDZ), and zeatin alone using leaf explants excised from in vitro germinated seedlings, while the second set tested the combinations of indole-3-butyric acid (IBA) with BAP, kinetin, TDZ, and zeatin for shoot multiplication from the leaf explants, which were already cultured and developed numerous shoots during the first set of experiments. For shoot regeneration (the first set of experiments), TDZ was the most eff ective at 1.0 mg L-1 concentration, producing a mean of 10.3 shoots per explant and was signifi cantly more eff ective than BAP. For shoot multiplication (the second set of experiments), a combination of 0.2 mg L-1 IBA with 0.2 mg L-1 TDZ produced signifi cantly more shoots per explant (16.5 shoots) than with BAP (11.0 shoots), zeatin (5.5 shoots), or kinetin (4.0 shoots). The regenerated shoots were readily rooted on medium containing 0.5 mg L-1 indole- 3-acetic acid (IAA). Rooted regenerants were then transferred to the pots, where they grew well and attained maturity. The described protocol provides a simple way to regenerate plants through direct shoot organogenesis, which would be useful for a large-scale production of cardenolides, germplasm conservation, and genetic transformation studies in this medicinally important endemic species.Öğe Direct somatic embryogenesis from hypocotyl segments of Digitalis trojana Ivan and subsequent plant regeneration(Elsevier, 2012) Verma, Sandeep Kumar; Şahin, Günce; Yücesan, Buhara; Eker, İsmail; Şahbaz, Nevin; Gürel, Songül; Gürel, EkremThis study describes, for the first time, an in vitro protocol for the direct development of somatic embryos and subsequent plant regeneration from hypocotyl segments excised from 21-days-old in vitro-germinated seedlings of Digitalis trojana Ivan (Helen of troy foxglove). Two sets of experiments were carried out, the first compared different concentrations of four cytokinins: N6-benzyladenine [BAP], 6-furfurylaminopurine [kinetin], 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea [TDZ], and 6-(4-hydroxy-3-methylbut-2-enylamino) purine [zeatin] I alone, while the second set tested TDZ or BAP combinations with IAA (indole-3-acetic acid), IBA (indole-3-butyric acid) or NAA (alpha-naphthalene acetic acid). In the first set of experiments, TDZ was found the most effective at 1.0 mg/l concentration, producing a mean of 10.7 somatic embryos per explant. In the second set, a combination of 1.0 mg/l TDZ with 0.5 mg/l IAA produced significantly more somatic embryos per explant (13.8 embryos) than with BAP (8.8 embryos). During subculture on growth regulator-free half-strength MS medium, somatic embryos gradually developed into plantlets. Regenerated plantlets were successfully transplanted and grown in a greenhouse environment. The efficient regeneration protocol reported here provides an important method of micropropagation of this plant. Furthermore, this protocol may be used for a large-scale production of cardenolides and genetic transformation of this valuable medicinal plant for its further improvement. (C) 2012 Elsevier B.V. All rights reserved.Öğe Düzeltme:Zn phthalocyanine conjugation to H2-ul aptamer for HER2-targeted breast cancer photodynamic therapy: Design, optimization and properties (vol 21, pg 887, 2017)(World Sci Publ Co Inc, 2019) Alpugan, Serkan; Topkaya, Derya; Verma, Sandeep Kumar; Atilla, Devrim; Ahsen, Vefa; Niazi, Javed H.; Dumoulin, FabienneTetrasulfonated Zn phthalocyanine was conjugated to a ssDNA aptamer moiety to produce a HER2 targeted photosensitizer. The tetraconjugate obtained was subjected to purification and the monoconjugate was successfully isolated, purified and characterized. This monoconjugate retained the ability to bind to HER2 as well as the potency to generate singlet oxygen.Öğe Embryogenesis, plant regeneration and cardiac glycoside determination in Digitalis ferruginea subsp ferruginea L(Springer, 2014) Verma, Sandeep Kumar; Yücesan, Buhara; Şahin, Günce; Gürel, EkremThe present study reports, for the first time, an efficient in vitro plant regeneration protocol for Digitalis ferruginea subsp. ferruginea L. (rusty foxglove). We have used different concentrations of gibberellic acid (GA(3)) on Murashige and Skoog (MS) medium to assess the germination frequency of seeds. High frequency of germination was achieved on MS medium with 1.0 mg l(-1) GA(3). 6-Benzylaminopurine (BAP) combined with alpha-naphtaleneacetic acid (NAA) or 2, 4-dichlorophenoxy acetic acid (2, 4-D) in the induction MS medium induced both somatic embryogensis and shoot organogenesis. The highest percentage of callus growth (85 %) was obtained when hypocotyl explants were cultured on MS medium containing 0.5 mg l(-1) 2, 4-D plus 1.0 mg l(-1) BAP. The maximum mean number of somatic embryos (7.3 +/- A 1.3 embryos) or shoots (12.0 +/- A 1.1 shoots) per callus was obtained when medium contained 0.25 mg l(-1) NAA plus 1.0 mg l(-1) BAP or 0.5 mg l(-1) NAA plus 2.0 mg l(-1) BAP. The regenerated shoots easily rooted on MS medium. Higher amounts of lanatoside C [13.2 +/- A 0.5 mg 100 g(-1) dry weight (dw)] and digoxin (2.93 +/- A 0.31 mg 100 g(-1) dw) accumulation were obtained when shoots were obtained by indirect regeneration. We also investigated derivatives of cardenolides, i.e., digitoxigenin (730 +/- A 180 mg 100 g(-1) dw), gitoxigenin (50 +/- A 20 mg 100 g(-1) dw) and digoxigenin (490 +/- A 170 mg 100 g(-1) dw) from natural samples.Öğe Engineered nanomaterials for plant growth and development: a perspective analysis(Elsevier, 2018) Verma, Sandeep Kumar; Das, Ashok Kumar; Patel, Manoj Kumar; Shah, Ashish; Kumar, VinayWith the overwhelmingly rapid advancement in the field of nanotechnology, the engineered nanomaterials (ENMs) have been extensively used in various areas of the plant system including quality improvement, growth and nutritional value enhancement, gene preservation etc. There are several recent reports on the ENMs influence on growth enhancements, growth inhibition as well as certain toxic impacts on plant. However, translocation, growth responses and stress modulation mechanisms of ENMs in the plant systems call for better and indepth understanding. Herein, we are presenting a comprehensive and critical account of different types of ENMs, their applications and their positive, negative and null impacts on physiological and molecular aspects of plant growth, development and stress responses. Recent reports revealed mixed effects on plants, ranging from enhanced crop yield, epiigenetic alterations, and phytotoxicity, resulting from the ENMs' exposure, Creditable research in recent years has revealed that the effects of ENMs on plants are species specific and are variable among plant species. ENM exposures are reported to trigger free radical formation, responsive scavenging, and antioxidant armories in the exposed plants. The ENMs are also reported to induce aberrant expressions of microRNAs, the key post-transcriptional regulators of plant growth, development and stress-responses of plants. However, these modulations, if judiciously done, may lead to improved plant growth and yield. A better understanding of the interactions between ENMs and plant responses, including their uptake transport, internalization, and activity, could revolutionize crop production through increased disease resistance, nutrient utilization, and crop yield. Therefore, in this review, we are presenting actitical account of the different selected ENMs, their uptake by the plants, their positive/negative impacts on plant growth and development, along with the resultant ENM-responsive post-transcriptional modifications, especially, aberrant m1RNA expressions. In addition, underlying mechanisms of various ENM-plant cell interactions have been discussed. (C) 2018 Published by Elsevier B.V.Öğe Enhanced growth and cardenolides production in Digitalis purpurea under the influence of different LED exposures in the plant factory(Nature Publishing Group, 2018) Verma, Sandeep Kumar; Gantait, Saikat; Jeong, Byoung Ryong; Hwang, Seung JaeIn this report, we have investigated the influence of different light qualities on Digitalis purpurea under a controlled environment. For this purpose, red (R), blue (B), fluorescent lamp (FL, control), along with combined red and blue (R: B) LEDs were used. Interestingly, the plant growth parameters such as number of leaf, longest root, width of leaf, width of stomata, width of trichome, leaf area, leaf or root fresh weight (FW), weight (DW) as well as length of trichome were maximum under R:B (8:2), and significantly larger than control plants. The stomatal conductance or anthocyanin was maximum under B LED than those under FL, however the photosynthesis rate was greater under FL. RuBisCO activity was maximum under R:B (1:1) LEDs while the quantity of the UV absorbing substances was highest under R LED than under FL. The maximum amount of cardenolides were obtained from leaf tissue under R:B (2:8) LED than those under FL. The R:B LEDs light was suitable for Digitalis plant growth, development, micro- and macro-elements, as well as cardenolides accumulation in the plant factory system. The adaptation of the growth strategy developed in this study would be useful for the production of optimized secondary metabolites in Digitalis spp.Öğe Enhanced somatic embryogenesis, plant regeneration and total phenolic content estimation in Lycium barbarum L.: a highly nutritive and medicinal plant(Springer, 2022) Verma, Sandeep Kumar; Gantait, Saikat; Mukherjee, Epsita; Gurel, EkremLycium barbarum (Solanaceae), commonly known as Goji (or wolfberry), is popular for its nutritive and medicinal properties and is called a “super fruit” or “super food”. Considering the importance of the economic utility, the potential of different explants (hypocotyl, leaf and root) of L. barbarum for plant regeneration and somatic embryogenesis has been evaluated in the present study. Two sets of experiments were carried out; the first compared Murashige and Skoog (MS) medium supplemented with different concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D), N6-benzylaminopurine, thidiazuron (TDZ), kinetin, and zeatin alone, while the second set tested the combinations of TDZ with 2,4-D to induce callus and subsequent shoot or embryo formation, respectively. For callus and subsequent shoot induction (for the first set of the experiment), 2,4-D was the most effective for callus induction (100%), while TDZ at 1 mg/L produced a mean of 5 shoots per callus. For the second set of experiment spontaneous induction of somatic embryos as well as subsequent maximum shoot regeneration was recorded in 0.25 mg/L 2,4-D+ 1 mg/L TDZ supplemented MS medium. Hypocotyl explant proved to be the most responsive organ that induced as many as 6 somatic embryos and subsequent 9 regenerated shoots per callus. Later, the plantlets were successfully acclimatized (100%) and finally transferred to the greenhouse. Total phenolic content was measured from shoot, brown callus and white callus of L. barbarum L. grown in MS medium supplemented with auxin alone (for callus) and auxin-cytokinin (for shoots). The highest amount of total phenolic content (640 mg GAE/g DW) was obtained in the shoot. The described protocol provides a simple way to regenerate plants through direct and indirect organogenesis as well as somatic embryogenesis, which would be useful for mass propagation, large-scale production of secondary metabolites, germplasm conservation, and genetic transformation studies in this medicinally important species. © 2022, The Author(s), under exclusive licence to Korean Society of Crop Science (KSCS).Öğe Exploring miRNAs for developing climate-resilient crops: A perspective review(Elsevier, 2019) Xu, Jin; Hou, Qin-Min; Khare, Tushar; Verma, Sandeep Kumar; Kumar, VinayClimate changes and environmental stresses have significant implications on global crop production and necessitate developing crops that can withstand an array of climate changes and environmental perturbations such as irregular water-supplies leading to drought or water-logging, hyper soil-salinity, extreme and variable temperatures, ultraviolet radiations and metal stress. Plants have intricate molecular mechanisms to cope with these dynamic environmental changes, one of the most common and effective being the reprogramming of expression of stress-responsive genes. Plant microRNAs (miRNAs) have emerged as key post-transcriptional and translational regulators of gene-expression for modulation of stress implications. Recent reports are establishing their key roles in epigenetic regulations of stress/adaptive responses as well as in providing plants genome-stability. Several stress responsive miRNAs are being identified from different crop plants and miRNA-driven RNA interference (RNAi) is turning into a technology of choice for improving crop traits and providing phenotypic plasticity in challenging environments. Here we presents a perspective review on exploration of miRNAs as potent targets for engineering crops that can withstand multi-stress environments via loss-/gain-of-function approaches. This review also shed a light on potential roles plant miRNAs play in genome-stability and their emergence as potent target for genome-editing. Current knowledge on plant miRNAs, their biogenesis, function, their targets, and latest developments in bioinformatics approaches for plant miRNAs are discussed. Though there are recent reviews discussing primarily the individual miRNAs responsive to single stress factors, however, considering practical limitation of this approach, special emphasis is given in this review on miRNAs involved in responses and adaptation of plants to multi-stress environments including at epigenetic and/or epigenomic levels. (c) 2018 Elsevier B.V. All rights reserved.Öğe How effective are stress-associated proteins in augmenting thermotolerance?(wiley, 2020) Karmous, Inès; Verma, Sandeep KumarAs the global temperature gradually increases, thermotolerance is vital to the growth and survival for plants. However, thermotolerance would be conferred through the expression of specific genes encoding proteins such as heat shock proteins (HSPs), proline, and dehydrins (DHNs). This chapter deals with the different types of stress-related proteins in response to heat-stress, and discusses their roles in augmenting potential for adaptation in repose to thermal stress. © 2020 John Wiley & Sons Ltd. All rights reserved.Öğe Hydrogen peroxide-induced antioxidant activities and cardiotonic glycoside accumulation in callus cultures of endemic digitalis species(Elsevier France-Editions Scientifiques Medicales Elsevier, 2014) Cingöz, Günce Şahin; Verma, Sandeep Kumar; Gürel, EkremThe effect of hydrogen peroxide (H2O2) on callus cultures of four Digitalis species (Digitalis lamarckii, Digitalis trojana, Digitalis davisiana and Digitalis cariensis) increased catalase (CAT), superoxide dismutase (SOD), total phenolic, proline activity and cardiotonic glycoside production. Callus derived from hypocotyl explants was cultured on Murashige and Skoog medium supplemented with 0.25 mg L-1 indole-3-acetic acid (IAA) and 0.5 mg L-1 thidiazuron (TDZ). After a month of culture, callus was transferred to MS medium containing 10 mM H2O2 and then incubated for 6 h. The amount of five cardenolides (Lanatoside C, Digitoxin, Digoxigenin, Gitoxigenin and Digoxin) as well as CAT, SOD, total phenolic, proline activity from Digitalis species were compared. No digoxin was detected in all treatments and control groups. The total cardenolides estimated were in the order of D. lamarckii (586.65 mu g g(-1) dw), D. davisiana (506.79 mu g g(-1) dw), D. cariensis (376.60 mu g g(-1) dw) and D. trojana (282.39 mu g g(-1) dw). It was clear that H2O2 pre-treatment resulted in an increase in enzymatic and nonenzymatic antioxidants. However, a significant negative relationship between cardenolides production and overall activities of CAT, SOD, total phenolic and proline was evident. The described protocol here will be useful for the development of new strategies for a large-scale production of cardenolides. (C) 2014 Elsevier Masson SAS. All rights reserved.Öğe Impacts of heavy metal, high temperature, and UV radiation exposures on bellis perennis l. (common daisy): Comparison of phenolic constituents and antioxidant potential (enzymatic and non-enzymatic)(Elsevier, 2022) Karakaş, Fatma Pehlivan; Şahin, Günce; Türker, Arzu Uçar; Verma, Sandeep KumarBellis perennis L., common daisy, is a beneficial medicinal plant used in folk medicine to treat skin diseases, wounds, sore throats, common colds, inflammation, and rheumatism. The objective of this study was to determine the effect of 4 different abiotic stress applications [mercury chloride (HgCl2), copper sulfate (CuSO4), high temperature (45 degrees C) and ultraviolet radiation (UV)] on individual phenolic constituents, nonenzymatic antioxidant activities (free radical scavenging activity, total phenol-flavonoid content, and proline level), and enzymatic antioxidant activities [superoxide dismutase (SOD) and catalases (CAT)] in common daisy callus cultures. Quantification of the 21 phenolic substances was performed using LC-ESI-MS/MS analysis and all applied stress applications increased specific phenolic constituents comparing with control (no exposure to any stress). Heavy metal stresses (HgCl2 and CuSO4) and high temperature application enhanced the quantity of the selected phenolic substances more than UV-radiation stress. The most noticeable increased quantities were observed with high temperature stress in p-coumaric acid (51.74-fold), and with CuSO4 stress in luteolin (17.76-fold) and apigenin (15.62-fold). Chlorogenic acid was the most prevalent phenolic compound in all tested callus extract including control. Although the first highest total phenol content was obtained with HgCl2 exposure and then followed by high temperature stress, the first highest total flavonoid content was obtained with high temperature stress and then UV radiation. The antioxidant capacity was significantly enhanced (2.11 fold increase) with CuSO4 stress application. Stress-related enzymatic antioxidant activity (SOD and CAT) was elevated the most with HgCl2 stress. Similarly, the highest proline content was obtained with HgCl2 treatment. These findings showed the ability of the phenolic compounds to protect common daisy against harmful heavy metals, high temperature and UV-radiation stresses. The adaptation of the callus under abiotic stress conditions developed here may be useful for the production of optimized phenolic compounds of common daisy and the exploitation of other medicinal species of interest. (C) 2022 SAAB. Published by Elsevier B.V. All rights reserved.Öğe In vitro culture of Digitalis L. (Foxglove) and the production of cardenolides: An up-to-date review(Elsevier Science Bv, 2016) Verma, Sandeep Kumar; Das, Ashok Kumar; Cingöz, Günce Şahin; Gürel, EkremDigitalis L. (Foxglove, Plantaginaceae) genus is a representative of several medicinal ornamental plants that are widely used in the production of herbal medicines. Since the eighteenth century, human civilizations have been using the extracts from several Digitalis species for treating heart-related ailments. The active ingredient in the medicine is cardiac glycosides. Cardenolides, which are constituents of cardiac glycosides, have an important role in tumor therapy. Certain pharmacologically active compounds including cardenolides are isolated from plants, as the structural complexity of cardenolides impede an easy chemical synthesis. In modern plant biotechnology research, production of cardenolides in large-scale using in vitro techniques has become the need of the hour. The reasons are twofold: first, to reduce the excessive use of natural Digitalis population and second, to improve the plant quality vis-a-vis genetic preservation of the superior seeds for future use. The production of useful secondary metabolites depends on the overall wellness of the plant from which extraction is to be made. The subject matter of this review includes concurrent development and propagation of several Digitalis species based on direct and indirect regeneration methods. Herein, a compilation of up-to-date published research reports on in vitro culture of Digitalis L has been presented, including the authors' latest and yet-to-be-published work on Digitalis davisiana Heywood. The important steps to be followed for the implementation of any plant improvement/preservation program must include topic-wise requirements at various stages of micro propagation (viz., culture establishment, shoot multiplication, root induction and acclimatization) and also the requirements for plant regeneration (viz., somatic embryogenesis and organogenesis). These have been reviewed thoroughly and different methods for the in vitro production of cardenolides have been discussed. Critical comments on the prospects of highly scalable cultures and their importance to meet the ever-growing demand for Digitalis-derived products in pharmaceutical industries, have also been included. (C) 2016 Elsevier B.V. All rights reserved.Öğe In vitro mature embryo culture protocol of einkorn (Triticum monococcum ssp. monococcum) and bread (Triticum aestivum L.) wheat under boron stress(Springer, 2022) Ağıl, Ferdi; Örgeç, Mehmet; Karakaş, Fatma Pehlivan; Verma, Sandeep Kumar; Zencirci, NusretMature embryos of einkorn (Triticum monococcum ssp. monococcum) and bread (Triticum aestivum L.) wheat were used for callus induction on media containing four diferent doses (0, 1, 2 and 4 mg L−1) of 2,4-D and dicamba supplemented with fve diferent boron concentrations (0, 6.2, 12.4, 24.8, and 37.2 mg L−1). The obtained callus was transferred to culture media with three (0, 0.5, and 2 mg L−1) diferent BAP doses with fve boron concentrations for further regeneration. The maximum callus weight in einkorn wheat was in culture media with 1 mg L−1 dicamba and 6.2 mg L−1 (3.71±0.13 g). Bread wheat had the maximum callus weight on culture media with 4 mg L−1 dicamba and 12.4 mg L−1 (3.46±0.40 g). The highest plantlet numbers were in only 2 mg L−1 BAP (2.92±0.88) for einkorn wheat and 0.5 mg L−1 BAP supplemented with 6.2 mg L−1 boron (3.71±1.12) for bread wheat. This indirect regeneration protocol using mature embryos of einkorn and bread wheat under boron stresses expected to be useful for future wheat breeding studies.Öğe In vitro plant regeneration of Ocimum basilicum L. is accelerated by zinc sulfate(Springer, 2016) Verma, Sandeep Kumar; Şahin, Günce; Das, Ashok Kumar; Gürel, EkremThis article describes a fast, simple, and efficient plant regeneration protocol for Ocimum basilicum L. Two sets of experiments were performed. The first set was performed on Murashige and Skoog (MS) medium lacking zinc sulfate heptahydrate (ZnSO4 center dot 7H(2)O) and containing varying concentrations of indole-3-acetic acid (IAA). The second set used three different concentrations (8.6, 12.9, and 17.2 mg L-1) of ZnSO4 center dot 7H(2)O along with varying concentrations of IAA. In the first set, without zinc sulfate, an IAA concentration of 1.0 mg L-1 (MS4) was found to be most effective, producing a mean of 12.6 roots per hypocotyl explant, while shoots were not produced. In the second set, with zinc sulfate, a combination of 12.9 mg L-1 ZnSO4 center dot 7H(2)O + 1.0 mg L-1 IAA (MS11) produced significantly more shoots per explant (15 shoots) than a combination of 12.9 mg L-1 ZnSO4 center dot 7H(2)O + 0.5 mg L-1 IAA (MS10), which produced only six shoots. Later, the plantlets were successfully acclimatized (100%) and finally transferred to the greenhouse (ex vitro). In the O. basilicum plants grown using MS11 medium, total phenolic content and rosmarinic acid content were estimated from stem, shoot tip, and old leaf tissue of in vitro plantlets, ex vitro plantlets, and flowering plants. The highest amounts of total phenolic content (131.8 mg gallic acid equivalent g(-1) DW) and rosmarinic acid (13.0 mg g(-1) DW) were obtained in the old leaf tissue at flowering time. This rapid regeneration protocol for O. basilicum L. represents a major improvement over the conventional protocols for plant regeneration and propagation of this species.Öğe In vitrotissue culture protocol of ancient einkorn (Triticum monococcumssp.monococum) wheat via indirect shoot regeneration(Springer, 2021) Örgeç, Mehmet; Verma, Sandeep Kumar; Şahin, Günce; Zencirci, Nusret; Gürel, EkremEinkorn indirect shoot regeneration was obtained from leaf, coleoptile, and root explants cultured on full, 1/2, and 1/4 strength Murashige and Skoog (MS) medium containing 0.5 to 10 mg L(-1)2,4-dichlorophenoxyacetic acid (2,4-D). Calluses derived from coleoptile and root explants were cultured on full-strength MS medium supplemented with 0.5 to 5 mg L(-1)thidiazuron (TDZ) for 6 wk to induce plant regeneration. Only callus cultures derived from coleoptile explants regenerated shoots. For root induction, 1.0 to 10 mg L(-1)indole-3-acetic acid (IAA) was used for 4 wk. The highest rate of callus formation (93%) was from root explants cultured on full-strength MS medium with 4 mg L(-1 )2,4-D. Coleoptile explants had the highest callus formation (100%) after culture on full-strength MS medium with 3 to 6 mg L(-1)of 2,4-D. The highest indirect shoot regeneration (7.0 +/- 1.1 shoots produced per callus with a 67% shoot formation frequency) was from calluses derived from coleoptile explant cultured on full MS medium supplemented with 5 mg L(-1)of TDZ. Of the different IAA concentrations investigated for rooting, the greatest number of roots per explant (7.7 +/- 0.088 roots produced per regenerated shoot with a 100% root formation frequency) was observed on MS medium supplemented with 6 mg L(-1)IAA. This indirect shoot regeneration protocol for coleoptile-derived einkorn wheat callus will be useful for future wheat genetic and improvement studies.Öğe Indirect somatic embryogenesis and shoot organogenesis from cotyledonary leaf segments of Digitalis Lamarckii Ivan., an endemic medicinal species(2011) Verma, Sandeep Kumar; Yücesan, Bahtiyar Buhara; Gürel, Songül; Gürel, EkremThis study describes, for the first time, an in vitro protocol for the development of somatic embryos and shoots from a callus derived from cotyledonary leaf segments excised from 3-week-old in vitro-germinated seedlings of Digitalis lamarckii Ivan. (dwarf foxglove), an endemic medicinal species of Turkey. The embryogenic callus was induced on Murashige and Skoog (MS) medium containing 0.54 μM α-naphthalene acetic acid (NAA) and 2.22 μM 6-benzylaminopurine (BAP). Somatic embryos developed readily when the embryogenic callus was transferred to MS medium containing BAP (4.44 or 8.87 μM) alone or BAP combined with NAA (1.34, 2.69, or 5.37 μM). The most effective hormonal combination for somatic embryogenesis was 1.34 μM NAA and 8.87 μM BAP, which produced a mean of 37.0 embryos per cotyledonary leaf explant. An organogenic callus was induced on MS medium containing 2.69 μM NAA and 2.22 μM BAP. Shoot development was observed when the organogenic callus was transferred to MS medium containing different concentrations of BAP alone (2.22, 4.44, or 8.87 μM) or BAP combined with NAA (1.34 or 2.69 μM). The highest mean number of shoots (5.67 shoots per explant) was obtained when the medium contained 8.87 μM BAP and 2.69 μM NAA. The regenerated shoots were readily rooted on MS medium containing 1.0, 2.5, or 5 μM indole-3-acetic acid (IAA) or indole-3-butyric acid (IBA). Rooted regenerants were then transferred to the pots, where they grew well and attained maturity. Over 90% of the regenerants survived the hardening process. The protocol described could be useful for germplasm conservation, commercial cultivation, genetic improvement, and cardenolide production studies in D. lamarckii.Öğe Influence of auxin and its polar transport inhibitor on the development of somatic embryos in Digitalis trojana(Springer Heidelberg, 2018) Verma, Sandeep Kumar; Das, Ashok Kumar; Gantait, Saikat; Gürel, Songül; Gürel, EkremThe present study reports the role of auxin and its transport inhibitor during the establishment of an efficient and optimized protocol for the somatic embryogenesis in Digitalis trojana Ivan. Hypocotyl segments (5 mm long) were placed vertically in the Murashige and Skoog medium supplemented with three sets [indole-3-acetic acid (IAA) alone or 2,3,5-triiodobenzoic acid (TIBA) alone or IAA-TIBA combination] of formulations of plant growth regulators, to assess their differential influence on induction and proliferation of somatic embryos (SEs). IAA alone was found to be the most effective, at a concentration of 0.5 mg/l, inducing similar to 10 SEs per explant with 52% induction frequency. On the other hand, the combination of 0.5 mg/l of IAA and 1 mg/l of TIBA produced significantly fewer (similar to 3.6 SEs) and abnormal (enlarged, oblong, jar and cup-shaped) SEs per explant with 24% induction frequency in comparison to that in the IAA alone. The explants treated with IAA-TIBA exhibited a delayed response along with the formation of abnormal SEs. Our study revealed that IAA induces high-frequency SE formation when used singly, but the frequency gradually declines when IAA was coupled with increasing levels of TIBA. Eventually, our findings bring new insights into the roles of auxin and its polar transport in somatic embryogenesis of D. trojana.Öğe Influence of nutrient media on callus induction, somatic embryogenesis and plant regeneration in selected Turkish crocus species(Elsevier B.V., 2016) Verma, Sandeep Kumar; Das, Ashok Kumar; Cingöz, Günce Şahin; Uslu, Emel; Gürel, EkremCallus induction, somatic embryogenesis and plant regeneration were initiated in selected five species of Turkish crocus using three diffrent explants (leaf, stem and corm) cultured on four different media (MS, GB5, LS and CHE). The highest frequencies of callus induction (100%) and shoot regeneration (70%, with 7.2 shoots/callus) were found in the crocus species Crocus oliveri ssp. Oliveri, using the MS medium containing 5% (w/v) sucrose supplemented with (4 mg/L NAA + 4 mg/L TDZ) and (2 mg/L IAA + 2 mg/L TDZ + 2 mg/L BAP). When the embryogenic calli were transferred into the four nutrient media containing (2 mg/L IAA + 2 mg/L TDZ) and 100 mg/L ABA, these further developed into cotyledonary embryos. Maximum number of somatic embryos (2.9 embryos per leaf explant, with a frequency 46.6%) was obtained in C. oliveri ssp. Oliveri. During subculture using the half strength media, cotyledonary embryos gradually developed into plantlets. © 2016 Published by Elsevier B.V.
