Showing papers on "Kinetin published in 1997"
TL;DR: A natural free radical scavenger, ascorbic acid (AsA) shows both counteractive and enhancing effects on JA‐inducible phytoalexin production, depending on its concentration, which suggests that active oxygen species (AOS) may play important roles in phy toalex in production by JA in rice leaves.
94 citations
TL;DR: Germination of Zygophyllum simplex seeds under various salinity, proline, betaine, GA and kinetin treatments was determined, and GA completely alleviated the effect of salinity at all concentrations used.
93 citations
TL;DR: Plant regeneration by somatic embryogenesis was attempted with diploid and triploid bananas and showed that the embryogenic process involves a sequence of similar events for both species.
Abstract: Plant regeneration by somatic embryogenesis was attempted with diploid (Musa acuminata ssp. malaccensis) and triploid ('Grand Nain') bananas. Explants inoculated in vitro were, respectively, immature zygotic embryos and male flower bud primordia. An histological study showed that the embryogenic process involves a sequence of similar events for both species. A yellow-green compact callus was initiated, which consisted of an actively dividing meristematic zone surrounded by several layers of starchy cells. A white and friable callus, characterized by the presence of proembryonic cells, bicellular proembryos and proembryonal masses in its periphery gradually appeared, which finally gave rise to somatic embryos from which plants were recovered. Induction media contained 2,4-D (and also NAA and IAA for the triploid); zeatin and kinetin were necessary for embryo maturation and 6-BA and IAA were used for germination.
84 citations
TL;DR: The process of callus induction, organogenesis and plantlets regeneration of Camptotheca acuminata Decne is reported, and the presence of 10-hydroxycamptothecin in shoots and callus is reported for the first time.
Abstract: The process of callus induction, organogenesis and plantlets regeneration of Camptotheca acuminata Decne is reported. The highest growth rate of callus was observed on MS medium with 1 mg l−1 NAA, 1 mg l−1 kinetin and 60 g l−1 sucrose. All tissues and organs developed in vitro contain camptothecin and 10-hydroxycamptothecin. The presence of 10-hydroxycamptothecin in shoots and callus of Camptotheca acuminata Decne is reported for the first time. The alkaloids were detected and identified using HPLC methods.
79 citations
TL;DR: Histological analyses indicated that in the absence of bialaphos morphogenesis was primarily via embryogenesis while organogenesis was more predominant in callus maintained with herbicide selection, and 5 herbicide resistant plants derived from two independent transformation events.
Abstract: Transgenic sorghum plants (Sorghum bicolor L. Moench, cv. SRN39) were obtained by microprojectile-mediated DNA delivery (Bio-Rad PDS 1000/He Biolistic Delivery System) to explants derived from immature inflorescences. Explants were precultured on medium supplemented with 2.5 mg/l (11.31 µM) 2,4-D, 0.5 mg/l (2.32 µM) kinetin, and 60 g/l sucrose for 1 to 2 wk prior to bombardment. Bialaphos selectron pressure was imposed 2 wk after bombardment and maintained throughout all the culture stages leading to plant regeneration. More than 2500 explants from 1.5 to 3.0 cm inflorescences were bombarded and subjected to bialaphos selection. Out of more than 190 regenerated plants, 5 were determined to be Ignite resistant. Southern analyses confirmed the likelihood that the 5 herbicide resistant plants derived from two independent transformation events. The phosphinothricin acetyltransferase gene (bar) was inherited by and functionally expressed in T1 progeny. However, no β-glucuronidase (GUS) activity could be detected in T1 plants that contained uidA restriction fragments. Histological analyses indicated that in the absence of bialaphos morphogenesis was primarily via embryogenesis while organogenesis was more predominant in callus maintained with herbicide selection.
78 citations
TL;DR: Hardening and survival of tissue culture plantlets was 95% under greenhouse conditions and in vitro shoots were rooted on half-strength agar-solidified MS basal medium or with 0.1 mg/1 naphthaleneacetic acid.
Abstract: Induction of multiple shoots in cotton (Gossypium hirsutum L. cv. Anjali-LRK 516) has been achieved with cotyledonary nodes devoid of cotyledons and apical meristems. Explants from 35-day-old seedlings yielded the maximum number of shoots (4.7 shoots/explant) using Murashige and Skoog (MS) basal medium supplemented with 6-benzylaminopurine and kinetin (2.5 mg/1 each). Explants from 35-day-old seedlings raised in glass bottles produced a higher number of multiple shoots (8.3 shoots/explant) than those grown in glass tubes and cultured on the same shoot induction medium. Elongation of multiple shoots was obtained on liquid or agar MS basal medium without phytohormones. In vitro shoots were rooted on half-strength agar-solidified MS basal medium or with 0.05 or 0.1 mg/1 naphthaleneacetic acid. Hardening and survival of tissue culture plantlets was 95% under greenhouse conditions.
78 citations
TL;DR: High-frequency bud break and multiple shoots were induced in apical shoot buds and nodal explants oforus cathayana, M. lhou and M. serrata on Murashige and Skoog medium containing 0.5–1.0 mg/l 6-benzylaminopurine along with gibberellic acid, which enhanced the frequency of bud break in all three species.
Abstract: High-frequency bud break and multiple shoots were induced in apical shoot buds and nodal explants ofMorus cathayana, M. lhou andM. serrata on Murashige and Skoog (MS) medium containing 0.5-1.0 mg/l 6-benzylaminopurine (BAP). Addition of gibberellic acid (0.4 mg/l) along with BAP induced faster bud break both in apical shoot buds and nodal explants and also enhanced the frequency of bud break in all three species. Shoot culture initiation was greatly influenced by explant type, explant age and explanting season. The shoots were successfully rooted on half-strength MS medium containing a combination of indole-3-acetic acid, indole-3-butyric acid and indole-3-propionic acid, each at 1.0 mg/l. The plantlets were successfully acclimated and eventually established in soil.
78 citations
TL;DR: Propagules of Dendrocalamus giganteus were produced by a process of in vitro axillary shoot proliferation followed by rooting, and the presence of culture contaminants in single-node segments of secondary branches were strongly influenced by the seasonal rainfall pattern.
74 citations
TL;DR: Kinetin is the first stable secondary DNA damage product known to date with very well defined cytokinin and anti‐aging properties, linked to oxidative processes in the cell, and is an important component of a new salvage pathway of hydroxy radicals constituting a ‘free radical sink’.
68 citations
TL;DR: The frequency of shoot regeneration was greatly influenced by the developmental stage and orientation of the leaf, and NAA at lower concentrations had no beneficial effects on shoot regeneration, whether added to the medium along with BA, Kn or TDZ, however, it promoted shoot elongation and leaf expansion.
Abstract: An efficient and reproducible procedure is described for the large-scale propagation of an epiphytic orchid,Acampe praemorsa (Roxb.) B latter and McCann using foliar explants. Shoot buds were induced in basal parts of foliar explants on Murashige and Skoog medium supplemented with N6-benzyladenine (BA), kinetin (Kn) or thidiazuron (TDZ), the latter being most effective at 1.0 mg/1. Shoots formed to a TDZ-containing medium elongated following transfer to a substrate supplemented with 2.0 mg/l 1-naphthaleneacetic acid (NAA) and 0.5 mg/1 BA. NAA at lower concentrations had no beneficial effects on shoot regeneration, whether added to the medium along with BA, Kn or TDZ. However, it promoted shoot elongation and leaf expansion. Higher concentrations of NAA suppressed shoot regeneration. The frequency of shoot regeneration was greatly influenced by the developmental stage and orientation of the leaf. Shoots regenerated from the foliar explants were rooted successfully on MS medium containing 1.0 mg/l indole-3-butyric acid. The plantlets were acclimated and eventually transferred to a garden.
65 citations
TL;DR: Results support the view that improved maintenance of the soma and prolongation of its life is achieved at the cost of decreased reproductive activity in Kn‐fed Zaprionus fruitflies.
Abstract: Kinetin, a cytokinin plant growth hormone, retards senescence in plants, delays aging in human cells in culture, slows down development of insects and prolongs their lifespan. We have now observed that the increased longevity of Kn-fed Zaprionus fruitflies was accompanied by an increase in the specific activity of catalase during developmental stages and in adult insects. In addition, the egg laying capacity of Kn-fed fruitflies was reduced drastically as compared with those kept on a normal diet. These results support the view that improved maintenance of the soma and prolongation of its life is achieved at the cost of decreased reproductive activity.
TL;DR: Several types of explants, growth regulators, sugars and gelling agents were tested to induce somatic embryogenesis in Anthurium scherzerianum Schott and converted to entire plants on a medium with 0.46 μM kinetin.
Abstract: Several types of explants, growth regulators, sugars and gelling agents were tested to induce somatic embryogenesis in Anthurium scherzerianum Schott For induction, leaf pieces from micropropagated plants were found to be the best explant on a medium with 18 μM 2,4-dichlorophenoxyacetic acid and a high sucrose concentration (6), solidified with Gelrite Somatic embryos converted to entire plants on a medium with 046 μM kinetin Plantlets were transferred to greenhouse conditions for evaluation of plant uniformity
TL;DR: Pre-sowing seed soaking treatments with kinetin, gibberellic acid and to a lesser extent indole-3-acetic acid alleviated salt stress effects as apparent from seedling dry mass and evolved more ethylene both under saline and non-saline conditions.
Abstract: Seedlings of the salt sensitive wheat cultivar C-306 evolved more ethylene than the salt tolerant cultivar Kharchia-65 under different levels of both chloride- and sulphate-dominated types of salinity. Pre-sowing seed soaking treatments with kinetin, gibberellic acid and to a lesser extent indole-3-acetic acid alleviated salt stress effects as apparent from seedling dry mass. Treated seedlings also evolved more ethylene both under saline and non-saline conditions. Ethrel did not affect seedling growth as well as ethylene production. Abscisic acid inhibited seedling growth and ethylene production under both types of salinity.
TL;DR: A protocol for plantlet formation at high frequency from somatic embryos is described, and substitution of BA and KN with 22.7 µm TDZ increased plant recovery from 86% to 92%.
Abstract: Peanuts (Arachis hypogaea L.) are widely cultivated as a rich source of protein and oil. Although protocols for the regeneration of peanut via somatic embryogenesis and organogenesis have been developed, most of them have resulted in low frequencies of plant recovery. In this report, we describe a protocol for plantlet formation at high frequency from somatic embryos. Morphologically abnormal somatic embryos germinated and produced roots only in medium devoid of growth regulators. Shoots emerged from the undeveloped plumule of these rooted embryos in medium containing both 6-benzyladenine (BA) and kinetin (KN), or in medium with thidiazuron (TDZ) alone. In Murashige and Skoog basal medium supplemented with 8.9 µm BA and 14 µm KN, 86% of the embryos developed shoots. Substitution of BA and KN with 22.7 µm TDZ increased plant recovery from 86% to 92%. Plants grown on TDZ had multiple shoots. Eighty-four percent of these plants survived in sandy soil and were grown to maturity.
TL;DR: Stem cuttings were the most suitable explants for multiple-shoot proliferation, and when cultured on a woody plant medium containing 2.5 μM BA produced axillary shoots which branched repeatedly, yielding an average of 27 shoots per explant after 6 weeks in culture.
Abstract: Various factors that affect culture establishment, shoot growth, proliferation and rooting ofIxora coccinea L., a woody shrub, were studied. Stem cuttings (decapitated shoot, three nodes) were the most suitable explants for multiple-shoot proliferation, and when cultured on a woody plant medium (WPM) containing 2.5 μM BA produced axillary shoots which branched repeatedly, yielding an average of 27 shoots per explant after 6 weeks in culture. Kinetin, 2-iP, zeatin and thidiazuron all induced multiple-shoot formation, but were less effective than BA. While the presence of IAA in the multiplication medium was detrimental to shoot proliferation, shoot growth was not affected by IAA. The production of large amounts of basal callus and vitrification of shoots were the major problems to be avoided in proliferating shoot cultures. Addition of TIBA to the multiplication medium markedly reduced basal callusing, while sealing the culture vessels with a fluorocarbon polymer (tetrafluoroethyleneperfluoroalkyl vinyl ether) film (Neoflon PFA film) almost completely eliminated vitrification. A reduction in the number of vitrified shoots was also achieved with AVG treatment. Following this protocol of using BA-supplemented WPM and Neoflon film, it would be possible to produce more than 100,000 plants from a single stem cutting in 1 year.
TL;DR: Of the four cytokinins tested (6-benzylaminopurine (BAP), thidiazuron (TDZ), zeatin, and kinetin), BAP induced shoot development most efficiently and was observed after preculture on medium with 5 mg/l BAP followed by transfer to 10 mg/L BAP.
Abstract: Nodes from 3- to 5-week-old in vitro plants of different cassava cultivars were cultured for 2-3 days on solid Murashige and Skoog basal medium supplemented with cytokinin to induce the enlargement of axillary buds. Subculture of these buds on the same medium resulted in multiple shoot formation within 4-6 weeks. Of the four cytokinins tested (6-benzylaminopurine (BAP), thidiazuron (TDZ), zeatin, and kinetin), BAP induced shoot development most efficiently. The best results were obtained with cultivar TMS 30555, in which 63% of the explants each produced at least 25 shoots on medium with 10 mg/l BAP. In cultivars that did not produce shoots, the addition of the surfactant Pluronic F-68 (2% wt/vol) raised the percentage of explants forming at least 5 shoots from 0 to 20-60%. Axillary buds were also used to dissect meristems and test their ability to regenerate into shoots. Shoot formation from meristems of six different cultivars was observed after preculture on medium with 5 mg/l BAP followed by transfer to 10 mg/l BAP.
TL;DR: The DNA extracted from hairy roots and from the roots of transgenic plants hybridized with the appropriate genomic probes in Southern blotting is taken as evidence of the stable genetic transformation in the 4 Gentiana species.
Abstract: Shoots of micropropagated Gentiana acaulis, G cruciata, G lutea, and G purpurea were inoculated with suspensions of Agrobacterium rhizogenes cells, strains ATCC 15834 or A4M70GUS Adventitious roots appeared at the sites of inoculation in all 4 species Root tips were excised and cultured on growth regulator-free media for 2-6 years They exhibited very high branching and plagiotropism Spontaneous bud initiation occurred in roots of G cruciata Roots of G lutea, G acaulis and G purpurea were cultured on media with high kinetin concentration, which induced the formation of friable callus tissues Only in G purpurea were these calluses organogenic Regenerated shoots of G cruciata and G purpurea gave rise to plants, that displayed the typical phenotypes of A rhizogenes-transformed plants: short internodes and rolled leaves In the roots of G acaulis and G cruciata, transformed with A rhizogenes A4M70GUS, a positive reaction with X-gluc indicated the activity of β-glucuronidase The DNA extracted from hairy roots and from the roots of transgenic plants hybridized with the appropriate genomic probes in Southern blotting This is taken as evidence of the stable genetic transformation in the 4 Gentiana species
TL;DR: A complete protocol was developed from meristem tip culture to field transfer and replaces the existing protocols for meristen tip culture of cotton.
Abstract: In order to develop transgenic plants via the biolistic gun method regenerable embryogenic tissues are required Meristem shoot tips of 19 cultivars of cotton were cultured on several media formulations and assessed for shoot and root development The best shoot development was observed on media containing 046 mM kinetin while rooting was observed on media containing 268 mM NAA and 046 mM kinetin No intervarietal variability was observed A complete protocol was developed from meristem tip culture to field transfer This methodology is simple and replaces the existing protocols for meristem tip culture of cotton
TL;DR: Protocols for in vitro plant regeneration via axillary and adventitious shoot regeneration were established in an important medicinal plant and direct de novo development of shoots from leaf segments was achieved using 13.31 µM BA along with 50 mg l-1 activated charcoal.
Abstract: Protocols for in vitro plant regeneration via axillary and adventitious shoot regeneration were established in an important medicinal plant, Aristolochia indica L. (Aristolochiaceae). Basal Murashige and Skoog's (MS) medium supplemented with 0.54 µM α-naphthaleneacetic acid (NAA) and 13.31 µM benzyladenine (BA) induced the maximum number of shoots (45-50) from shoot tip and nodal segment cultures. Phenolic accumulation in leaf and internodal stem derived callus cultured in MS medium containing NAA or 2,4-dichlorophenoxyacetic acid and BA or kinetin was controlled by the addition of 1.0 mg l-1 phloroglucinol (PG) to the callus induction medium. Basal medium supplemented with 2.69 µM NAA, 13.31 µM BA and 1.0 mg l-1 PG induced the best results in terms of shoot bud regeneration from leaf derived callus. Direct de novo development of shoots from leaf segments was achieved using 13.31 µM BA along with 50 mg l-1 activated charcoal. The microshoots were rooted in White's medium supplemented with 2.46 µM indolebutyric acid. More than 85% of rooted plants survived in the soil.
TL;DR: In Iris germanica L., 'G1', 'Adorn' and 'Rococo', induction and proliferation of embryogenic calli were achieved by culture of leaf-base explants on Murashige and Skoog medium supplemented with 1 mg l−1 2,4-D, 1 mgL−1 kinetin, 200 mg l −1 casein hydrolysate, 250 mg l–1 proline and 30 g l− 1 sucrose.
Abstract: In Iris germanica L., 'G1', 'Adorn' and 'Rococo', induction and proliferation of embryogenic calli were achieved by culture of leaf-base explants on Murashige and Skoog (MS) medium supplemented with 1 mg l−1 2,4-D, 1 mg l−1 kinetin, 200 mg l−1 casein hydrolysate, 250 mg l−1 proline, 30 g l−1 sucrose and 2.5 g l−1 gellan gum. Among these cultivars, however, only in 'G1' could a suspension culture be established using a liquid N6 medium with 1 mg l−1 2,4-D, 1 mg l−1 kinetin, 200 mg l−1 casein hydrolysate, 250 mg l−1 proline and 30 g l−1 sucrose. Murashige and Skoog medium with 1 mg l−1 gibberellic acid (GA3), 30 g l−1 sucrose and 2.5 g l−1 gellan gum was suitable for somatic embryo formation from suspension cells. When the somatic embryos were transferred to solid, growth regulator-free MS medium and subcultured monthly, 36 shoots were obtained from 20 mg suspension cells.
01 Jan 1997
TL;DR: In this paper, the authors obtained a fibrillar network on the surface of the somatic proembryos from floret explants of Stevia rebaudiana cultured on MS medium supplemented with 2,4-D and kinetin (0 to 9.29 μM).
Abstract: Somatic embryogenesis was obtained from floret explants of Stevia rebaudiana cultured on MS medium supplemented with 2,4-D (9.05 and 18.10 μM) and kinetin (0 to 9.29 μM). On 9.05μM 2,4-D supplemented medium maximum embryogenic callus formation occurred in medium without kinetin. On 18.10 μM 2,4-D supplemented medium the best treatment was 2.32 μM kinetin. Embryogenic callus started at the base of the corolla and ovary. Histological sections showed a fibrillar network on the surface of somatic proembryos. An unicellular origin of the somatic embryos is proposed. Additional
TL;DR: Somatic embryogenesis was achieved in callus cultures dervied from 40-day-old semimature zygotic embryos of Dalbergia sissoo on semi-solid Murashige and Skoog (MS) salts and vitamins supplemented with 0.46–1.46-1.16 μM kinetin and 6.78–9.04 μM 2,4-D with 2% (w/v) sucrose.
Abstract: Somatic embryogenesis was achieved in callus cultures dervied from 40-day-old semimature zygotic embryos ofDalbergia sissoo on semi-solid Murashige and Skoog (MS) salts and vitamins supplemented with 0.46–1.16 μM kinetin, 6.78–9.04 μM 2,4-dichlorophenoxy acetic acid (2,4-D) and 30 g/1 sucrose. Somatic embryos proliferated rapidly by secondary somatic embryogenesis after transfer to half-strength basal MS medium supplemented with 0.46-1.16 μM kinetin and 6.78–9.04 μM 2,4-D with 2% (w/v) sucrose. The light-green somatic embryos germinated on half-strength MS salts and vitamins supplemented with 0.5 mg/1 abscisic acid and 2% (w/v) sucrose. The developmental stages of somatic embryogenesis were studied by light and scanning electron microscopy.
TL;DR: The rate of survival and endogenous free proline content of the plants regenerated from the NaCl adapted callus was significantly higher than for those obtained from unadapted callus in liquid maintenance media supplemented with NaCl.
Abstract: NaCl adapted callus of a salt sensitive scented indica variety of rice (Oryza sativa var Basmati 370) showed 55% regeneration in culture medium supplemented with IAA and kinetin Regeneration was low in 85 mM NaCl but a concentration of 128 mM was inhibitory to regeneration SEM study revealed organogenesis and somatic embryogenesis from the same callus The rate of survival and endogenous free proline content of the plants regenerated from the NaCl adapted callus was significantly higher than for those obtained from unadapted callus in liquid maintenance media supplemented with NaCl
TL;DR: This plant regeneration procedure has been exploited in preliminary studies of Agrobacterium-mediated transformation and is described as a reliable plant regeneration system for the production of adventitious shoots from root explants of spinach.
Abstract: A reliable plant regeneration system is described for the production of adventitious shoots from root explants of spinach. Explants from roots of axenic shoots and roots induced on cultured hypocotyl explants were used for adventitious shoot induction. Explants from apical, middle and basal root regions were incubated on Nitsch and Nitsch medium supplemented with α-naphthaleneacetic acid, gibberellic acid and kinetin. Optimum shoot regeneration was from explants of apical and middle root regions on medium with 20 µm
α-naphthaleneacetic acid and 5.0 µm gibberellic acid. Shoots originated directly from root tissues without an intervening callus phase. Adventitious shoots were rooted and were grown to maturity in the glasshouse. This plant regeneration procedure has been exploited in preliminary studies of Agrobacterium-mediated transformation.
TL;DR: Treatment with kinetin appears to be useful for breaking the considerable dormancy commonly observed in the dehusked seeds of indica rice under aerobic and anaerobic conditions.
TL;DR: Nodal cuttings of in vitro grown potato plants (Solanum tuberosum, cv Miranda) were transformed by a vector plasmid carrying ipt gene of Agrobacterium tumefaciens, which displayed in varying degree shortening of the internodes, decreases of the leaf size, decrease of apical dominance and poor rooting.
Abstract: Nodal cuttings of in vitro grown potato plants (Solanum tuberosum, cv. Miranda) were transformed by a vector plasmid carrying ipt gene of Agrobacterium tumefaciens. From the initial teratoma stage 5 clones of transgenic plants (1, 2, 11, 13 and 15) were obtained, which displayed in varying degree shortening of the internodes, decrease of the leaf size, decrease of apical dominance and poor rooting. In addition, two of the clones (11 and 13) showed increased stolon and tuber formation. In all these clones the endogenous level of free cytokinins (CKs) was increased: from 40% in clone 11 to almost 300% in clone 1. Also free indole-3-acetic acid (IAA) level was increased, but to a lower degree; the maximal increase was 160% (clone 13). Applied kinetin or IAA (1 mg·l-1) strongly suppressed root and tuber formation in clones 11 and 13, although they did not affect or even stimulated these processes in control plants. For control plants the minimal medium sucrose concentration necessary for tuber initiation was 6% whereas in clone 11 plants 2% was sufficient. Different distribution of endogenous CKs and IAA was observed in clone 11 and control plants. The highest CK content was found in transgenic plants in stems and in controls in leaves. In clone 11 plants abscisic acid (ABA) level was significantly increased in comparison to the control throughout the cultivation period. Ethylene formation was strongly increased the first week after the subcultivation and later on the difference between transgenic and control plants rapidly diminished. Reactions of clone 11 plants to red (RL) and blue light (BL) were similar to reactions of control plants. In RL clone 11 plants were tall and thin with stunted leaves; in BL they had a teratoma-like appearance and formed a very high number of tubers. The role of hormones in these changes in growth and tuber formation is discussed.
TL;DR: The influence of different auxins and cytokinins on somatic embryogenesis was investigated and 2,4-dichlorophenoxy acetic acid was the most effective and resulted in the highest frequency of responding cultures and highest average number of somatic embryo per responding cultures.
Abstract: Somatic embryos were induced from hypocotyl-derived callus of sesame (Sesamum indicum Var TMV 6) The influence of different auxins and cytokinins on somatic embryogenesis was investigated Among the different auxins tested, 2,4-dichlorophenoxy acetic acid was the most effective and resulted in the highest frequency of responding cultures and highest average number of somatic embryo per responding cultures napthaleneacetic acid, indoleacetic acid, indolebutyric acid and 2,4,5-trichlorophenoxypropionic acid were also effective for embryogenesis, but 2,4,5-trichorophenoxyacetic acid and napthoxyacetic acid were not beneficial The combined effect of cytokinins with 2,4-d was also studied Among the four cytokinins tested, 22 chμM benzyladenine with 136 chμM 2,4-d slightly enhanced embryogenic efficiency; while kinetin, zeatin, 6-γ-γ-dimethylallylaminopurine enhanced the frequency of responding cultures There was a decrease in the number of somatic embryos per culture in the presence of all cytokinins
TL;DR: Callus cultures of Agave sisalana were initiated from rhizome, and stem explants on MS, SH, Gamborg and White's medium supplemented with different concentrations of BA, kinetin, NAA, IAA and 2,4-D either in combination or singly.
Abstract: Callus cultures of Agave sisalana were initiated from rhizome, and stem explants on MS, SH, Gamborg and White's medium supplemented with different concentrations of BA, kinetin, NAA, IAA and 2,4-D either in combination or singly. Optimum numbers of shoots were obtained from stem and rhizome explants either directly or from callus. The capacity for the shoot regeneration remained constant in the callus for more than 32 months. Regenerated shoots rooted readily within 21-35 days on fine sand with half the strength of inorganic salts of MS medium. 100% of the rooted plants successfully adapted to field conditions and grown in the soil. Regenerated plants were morphologically similar to the field grown mother plants.
TL;DR: High-frequency somatic embryogenesis was achieved from an embryogenic cell suspension culture of Acanthopanax koreanum Nakai and Cytokinin treatment suppressed the normal growth of embryos, but stimulated secondary somatic embryos from the surfaces of primary embryos.
Abstract: High-frequency somatic embryogenesis was achieved from an embryogenic cell suspension culture of Acanthopanax koreanum Nakai. Stem segments were cultured on Murashige and Skoog (MS) medium containing auxins and cytokinins. Opaque and friable embryogenic callus formed on MS medium with 4.5 µm 2,4-dichlorophenoxyacetic acid (2,4-D) and 2.0 µm kinetin or zeatin, but was highest on medium containing 4.5 µm 2,4-D alone. Embryogenic calli were transferred to MS liquid medium containing 4.5 µm 2,4-D and maintained by subculture at 2-week intervals. Initiation of somatic embryogenesis and development up to the globular stage from embryogenic cell clumps occurred in medium containing 0.45 µm 2,4-D, whereas maturation and germination of somatic embryos occurred in MS medium lacking 2,4-D. Cytokinin treatment suppressed the normal growth of embryos, but stimulated secondary somatic embryogenesis from the surfaces of primary embryos. Plants from somatic embryos were acclimatized in a greenhouse.
TL;DR: The adventitious origin of shoots regenerated from stem explants was confirmed by scanning electron microscopy, and the regeneration procedure was found to be applicable to five other gypsophila cultivars (Perfecta, Golan, Gilboa, Flamingo and Tavor).
Abstract: An efficient adventitious shoot regeneration procedure was developed for Gypsophila paniculata L. Using cultivar Arbel, shoot regeneration from the three upper internodes of the stem was monitored on MS media supplemented with different cytokinins (thidiazuron, benzyladenine, kinetin or zeatin) and an auxin (naphthaleneacetic acid). Thidiazuron was found to be the most efficient cytokinin, with up to 100% of the explants forming shoots, at an average of up to 19 shoots per explant being regenerated. The highest percentage of shoot formation was observed in the stem explants originating from the first internode, with all cytokinins tested. The adventitious origin of shoots regenerated from stem explants was confirmed by scanning electron microscopy. The regeneration procedure was found to be applicable to five other gypsophila cultivars (Perfecta, Golan, Gilboa, Flamingo and Tavor). Regenerating plants were successfully transferred to soil, and did not differ in flower color, size or shape from standard vegetatively propagated plants derived from cuttings.