Showing papers on "Murashige and Skoog medium published in 1994"
TL;DR: In vitro clonal multiplication of safed musli (Chlorophytum borivilianum Sant. Fernand.), a rare Indian medicinal herb, has been achieved on Murashige and Skoog's MS medium supplemented with 22.2 μM benzyladenine using young shoot bases as explants.
Abstract: In vitro clonal multiplication of safed musli (Chlorophytum borivilianum Sant. et. Fernand.), a rare Indian medicinal herb, has been achieved on Murashige and Skoog's (MS) medium supplemented with 22.2 μM benzyladenine using young shoot bases as explants. Shoots multiplied at a rate of four-fold every 3 weeks. All shoots rooted when transferred to MS medium with 3/4-strength inorganic and organic constituents and 9.8 μM indolebutyric acid and 67% of the micropropagated plants were successfully established in pots. Such plants produced normal fasciculated storage roots as in wild plants.
124 citations
TL;DR: Plant regeneration, which is the major limiting factor for transformation of Cajanus cajan, has been obtained via multiple shoot formation from the cotyledonary node region of seedlings germinated on MS medium containing 2 mgl−1 6-benzylaminopurine.
Abstract: Plant regeneration, which is the major limiting factor for transformation of Cajanus cajan, has been obtained via multiple shoot formation from the cotyledonary node region of seedlings germinated on MS medium containing 2 mgl−1 6-benzylaminopurine. A mass of multiple shoot-initials formed at the axillary bud region of the cotyledonary node of the seedlings within two weeks. The cotyledonary node along with the mass of shoot-initials excised from the seedling, continued to form new shoot-initials on MS medium containing 6-benzylaminopurine (2 mgl−1) and supplemented topically with indole-3-acetic acid. The formation of new shoot-initials was also observed from the cotyledonary nodal explant, after cutting off its surface layers to completely remove the pre-existing shoot-initials and culturing it on 6-benzylaminopurine (2 mgl−1) containing medium. The shoots elongated rapidly on basal MS medium and rooted efficiently in MS medium supplemented with indole-3-butyric acid (0.5 mgl−1). The procedure described is efficient, and highly reproducible and a common response was observed for all the six varieties tested.
115 citations
TL;DR: An embryogenic tissue characterized by compact consistency and pearly white color was observed in tissues derived from very young inflorescences in oil palm inflorescence expiants.
Abstract: Immature inflorescences of oil palm (Elaeis guineensis) var. Pisifera were inoculated onto modified MS medium containing 0.3% (w/v) activated charcoal and 475 μM 2,4-D. After 2—3 months of culture, a hard yellow callus proliferated at the base of the shoot-like structures. The high incidence of phenolic oxidation required the use of increased levels of activated charcoal (0.5% w/v) and 2,4-D (500 μM). Development of floral structures from inflorescence expiants was frequently observed during the culture period. After 81 weeks of culture, an embryogenic tissue characterized by compact consistency and pearly white color was observed in tissues derived from very young inflorescences. This compact embryogenic tissue differentiated into normal somatic embryos when transferred onto regeneration medium containing NAA (15 μM) and ABA (2 μM). Normal plantlets were recovered from these somatic embryos after 8 weeks on regeneration medium.
111 citations
TL;DR: Sexually-mature mungbean (Vigna radiata (L.) Wilczek) plants were efficiently regenerated from cotyledonary node explants capable of directly developing multiple shoots on basal media devoid of any growth regulators.
Abstract: Sexually-mature mungbean (Vigna radiata (L.) Wilczek) plants were efficiently regenerated from cotyledonary node explants. The explants were capable of directly developing multiple shoots on basal media devoid of any growth regulators. The shoot multiplication was influenced by media composition, growth regulators, age of donor seedling and explant type. The explants with both the cotyledons attached to the embryonic axis excised from 4-d-old seedlings, produced the highest number of shoots (5 or 6) in 100% of the cultures within 2 weeks on B5 basal medium (BBM) containing BAP or 2-iP, respectively, (at 5x10−7M) and 3% sucrose. Shoots elongated and developed better using BAP. Increasing micronutrients, carbohydrate and nitrogen levels in the medium above the original formulation of B5 basal medium appeared to be of no benefit for increasing the number of shoots. The shoots were rooted on basal MS medium or MS containing 10−6 of NAA, IAA or IBA. This protocol was found applicable to six other cultivars of mungbean. One hundred rooted shoots were successfully established in soil in the glasshouse, where 90% of them survived. The regenerated plants flowered precociously, but produced normal pods and viable seeds.
93 citations
TL;DR: To obtain transformed plants, cotyledonary explants of ‘Sweet Gem’ were cocultured with Agrobacterium tumefaciens LBA4404, a disarmed strain harboring a binary vector pBI121 carrying the CaMV 35S promoter-β-glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker.
Abstract: Adventitious shoots formed on the proximal cut edges of different cotyledonary explants of watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai; cvs. Sweet Gem and Gold Medal] cultured on Murashige and Skoog's (MS) medium with 1 mgl-1 6-benzyladenine (BA). Light (16-h photoperiod, about 7 Wm-2 cool-white fluorescent lamps) was essential for shoot formation. To obtain transformed plants, cotyledonary explants of ‘Sweet Gem’ were cocultured with Agrobacterium tumefaciens LBA4404, a disarmed strain harboring a binary vector pBI121 carrying the CaMV 35S promoter-β-glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker, for 48 h on MS medium with 1 mgl-1 BA and 200 μM β-hydroxyacetosyringone. After 48 h of culture, explants were transferred to medium with 1 mgl-1 BA 250 mgl-1 carbenicillin, and 100 mgl-1 kanamycin and cultured in the light. Adventitious shoots formed on the explants after 4 weeks of culture. When subjected to GUS histochemical assay, young leaves obtained from the shoots showed a positive response at a frequency of up to 16%. Preculturing cotyledonary explants on MS medium with 1 mgl-1 BA for 5 d enhanced the competence of the cells to be transformed by Agrobacterium. Southern blot analysis confirmed that the GUS gene was incorporated into the genomic DNA of the GUS-positive regenerants. The transformed plants were grown to maturity.
90 citations
TL;DR: Flow cytometry analysis of leaf tissue revealed that a significant number of transgenic plants were tetraploid or mixoploid, whereas the commercial nontransformed cultivars were diploid, while in a study of young, germinated cotyledons, a mixture of diploids, tetraPloid, and octoploid cells were found at the shoot regeneration sites.
Abstract: A single regeneration procedure using cotyledon explants effectively regenerated five commercially grown muskmelon cultivars. This regeneration scheme was used to facilitate gene transfers using either Agrobacterium tumefaciens (using 'Burpee Hybrid' and 'Hales Best Jumbo') or microprojectile bombardment (using 'Topmark') methods. In both cases, the transferred genes were from the T-DNA region of the binary vector plasmid pGA482GG/cp cucumber mosaic virus-white leaf strain (CMV-WL), which contains genes that encode neomycin phosphotransferase II (NPT II), β-glucuronidase (GUS), and the CMV-WL coat protein (CP). Explants treated with pGA482GG/cpCMV-WL regenerated shoots on Murashige and Skoog medium containing 4.4 μM 6-benzylaminopurine (BA), kanamycin (Km) at 150 mg·liter -1 and carbenicillin (Cb) at 500 mg·liter -1 . Our comparison of A. tumefaciens- and microprojectile-mediated gene transfer procedures shows that both methods effectively produce nearly the same percentage of transgenic plants. R 0 plants were first tested for GUS or NPT II expression, then the polymerase chain reaction (PCR) and other tests were used to verify the transfer of the NPT II, GUS, and CMV-WL CP genes. This analysis showed that plants transformed by A. tumefaciens contained all three genes, although co- transferring the genes into bombarded plants was not always successful. R 1 plants were challenge inoculated with CMV-FNY, a destructive strain of CMV found in New York. Resistance levels varied according to the different transformed genotypes. Somaclonal variation was observed in a significant number of R 0 transgenic plants. Flow cytometry analysis of leaf tissue revealed that a significant number of transgenic plants were tetraploid or mixoploid, whereas the commercial nontransformed cultivars were diploid. In a study of young, germinated cotyledons, however, a mixture of diploid, tetraploid, and octoploid cells were found at the shoot regeneration sites.
79 citations
TL;DR: Efficient plant regeneration via somatic embryogenesis has been developed in chickpea cultivar C235 through somatic embryos with high efficiency during dark incubation and hardened plantlets produced normal, fertile plants upon transfer to soil.
Abstract: Efficient plant regeneration via somatic embryogenesis has been developed in chickpea cultivar C235. Leaf explants, on MS medium supplemented with 1.25 mg/l 2,4-D and 0.25 mg/l kinetin, yielded somatic embryos with high efficiency during dark incubation. MS medium supplemented with B5 vitamins, 0.125 mg/l IBA and 2 mg/l BAP was found suitable for embryo maturation. The well formed embryos germinated into plantlets on basal B5 medium supplemented with 0.25 mg/l BAP. Further development into healthy plantlets was obtained on basal B5 medium. Hardened plantlets produced normal, fertile plants upon transfer to soil.
73 citations
TL;DR: In this paper, the production of anthocyanins was investigated, controlling sugar concentration and ratio of ammonium: nitrate in culture medium of strawberry, Fragaria ananassa cv Shikinari.
Abstract: Production of anthocyanins was investigated, controlling sugar concentration and ratio of ammonium: nitrate in culture medium of strawberry, Fragaria ananassa cv Shikinari. Anthocyanins were produced under 8000 lux for 2 wk using calli derived from suspension cultures of leaf tissues. Yield was greatest in modified LS medium containing 5% sucrose (W/V), a ratio of NH+3 (2 mM):NO−3 (28mM), 2,4-dichlorophenoxyacetic acid and benzyladenine. Total anthocyanin was about 15 mg/100 mL of culture medium, almost six times greater than that in MS medium. Effects of sugars were also studied using eight sugars. Cell growth and anthocyanin accumulation were enhanced by glucose, sucrose, and fructose, but anthocyanin compositions were not affected. Major anthocyanins were peonindin-3-glucoside and cyanidin-3-glucoside. Peonidin-3-glucoside increased with an increase in the NH+4 NO−3 ratio at nitrogen concentration 30 mM, while that of cyanidin-3-glucoside changed vice versa.
70 citations
TL;DR: An efficient, high-frequency transformation protocol was developed for the commercial chrysanthemum cultivar ‘Iridon’ and Regeneration protocols were also developed for two other commercial cultivars, ‘Hekla” and ‘Polaris’.
70 citations
TL;DR: Regenerants from TIBA plus BA or kinetin media were successfully established in the soil (86% survival rate), where they flowered and showed normal meiotic behaviour with 100% pollen viability and plantlets obtained were normal diploids while those from BA or Kinetin alone revealed distinct chromosomal aberrations in their root tip squashes.
Abstract: The effect of various concentrations of benzyladenine (BA 4.4–177.5 μM) or kinetin (4.7–185.9 μM) on shoot proliferation from shoot-tip explants was investigated in C. praetermissum Heiser & Smith and C. annuum L. Maximum number of shoots were obtained on Murashige & Skoog's medium with 66.6 μM BA or 92.9 μM kinetin in C. praetermissum, and 88.8 μM BA or 116.2 μM kinetin in C. annuum after 4 weeks of culture. Combining 1 μM 2, 3, 5-triiodobenzoic acid (TIBA) with low levels of BA or kinetin significantly increased shoot number as compared to using either cytokinin alone. Rooting of regenerated shoots was achieved on MS medium containing 5.7 μM indoleacetic acid. Best rooting (80–100%) was observed in shoots from TIBA plus BA or kinetin media while only 40–50% of shoots from the BA or kinetin treatments were rootable. Plantlets obtained from TIBA plus BA or kinetin were normal diploids while those from BA or kinetin alone revealed distinct chromosomal aberrations in their root tip squashes. Regenerants from TIBA plus BA or kinetin media were successfully established in the soil (86% survival rate), where they flowered and showed normal meiotic behaviour with 100% pollen viability.
67 citations
TL;DR: Regarding artemisinin content, while the values obtained were 1.13 and 0.78 mg gDW-1 in primary callus, art Artemisinin was not detected in cell suspension and only traces of it were found in multiple shoot cultures.
Abstract: Dedifferentiated and differentiated tissue cultures ofArtemisia annua L. for artemisinin production were carried out. The calluses were initiated on MS medium supplemented with sucrose (30 g l-1), myoinositol (100 mg l-1) and RT vitamins. The auxins used were naphtaleneacetic acid (NAA), indoleacetic acid (IAA), indolebutyric acid (IBA) and 2,4-dichlorophenoxyacetic acid (2,4-d). These were added to the basal medium either singly or in combination. The best results were obtained with 2.4-d (4.5 μM : μ0.02 d-1) and NAA (5.4 μM : μ 0.06 d-1). Cell suspensions were established on the same media without agar. Suspension cultures showed different morphological characteristics according to the plant growth regulator supplied. Organized cultures were initiated from callus obtained on 2,4-d (4.5 μM) and from bud cultures. Medium containing 6-benzylaminepurine (BA) (8.9 μM)+NAA (0.54 μM); Zeatin (45.62 μM)+NAA (5.37 μM) or BA (8.9 μM) stimulated both organogenesis in callus (frequency of induction =50%) and semi-organized tissue in shoot buds. BA (13.32 μM)+NAA (1.08 μM) or BA (13.32 μM) only stimulated multiple shoot cultures (frequency of induction =80%). Regarding artemisinin content, while the values obtained were 1.13 and 0.78 mg gDW-1 in primary callus, artemisinin was not detected in cell suspension and only traces of it were found in multiple shoot cultures.
TL;DR: Clonal micropropagation was established by shoot tip culture and was maintained on Murashige and Skoog medium supplemented with kinetin and gibberellic acid A 3 and callus that was induced and maintained on supplements of 2,4-dichlorophenoxyacetic acid and 6-benzylaminoputine in the absence of light.
Abstract: Callus tissue from petioles of Salvia miltiorrhiza was obtained on Murashige and Skoog medium supplemented with indole-3-butyric acid and 6-benzylaminopurine. When the calli were subcultured, adventitious shoots formed. These shoots developed into normal plantlets with roots when transferred to hormone-free Murashige and Skoog medium. Clonal micropropagation was established by shoot tip culture and was maintained on Murashige and Skoog medium supplemented with kinetin and gibberellic acid A 3 . Callus that was induced and maintained on supplements of 2,4-dichlorophenoxyacetic acid and 6-benzylaminoputine in the absence of light produced rosmarnic acid (1.24% dry wt) and lithospermic acid B (0.10% dry wt)
TL;DR: Stem cuttings of potato plants were cultured in vitro on MS medium with sucrose either without or with addition of indole-3-acetic acid (IAA) or kinetin (K) under red light (R) or blue light (B).
Abstract: Stem cuttings of potato plants (Solanum tuberosum L., cv. Miranda) were cultured in vitro on MS medium with sucrose either without or with addition of indole-3-acetic acid (IAA) or kinetin (K) under red light (R) or blue light (B). Plants on medium without hormones under R were thin, long, with very small leaves, and produced no or only a few microtubers (after longer-lasting cultivations). In B, plants remained short, thick, with large, wellde-veloped leaves and produced a significant amount of microtubers. Darkening of both roots and shoots strongly promoted tuber formation; the tubers were formed on the darkened part of the plant. IAA had no pronounced effect on plant development in B except for slight lengthening of the stem, and, in longer cultivations, slightly enhanced tuber formation as well. In R, IAA brought about several significant effects: stem reduction and induction of tuber formation being the most significant. Kinetin in R increased tuber formation slightly. In B, kinetin not only strongly stimulated tuber formation, but also increased the total fresh weight and root (+ stolons)/shoot ratio. Results are discussed with regard to the possible role of auxins and/or cytokinins in mediating the morphogenetic effects of light.
TL;DR: Developing protocols in which plants could be regenerated with ease and in high numbers from tissue cultures of switchgrass to produce high frequency plantlet regeneration by both organogenesis and somatic embryogenesis.
Abstract: Regeneration from cells or tissues cultured in vitro is a fundamental requirement for most applications of plant biotechnology. The objective of this study was to develop protocols in which plants could be regenerated with ease and in high numbers from tissue cultures of switchgrass (Panicum virgatum L.). Mature caryopses and young leaf segments of the cultivar Alamo were explanted onto agar solidified Murashige and Skoog medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzylaminopurine (BAP). BAP at 45 μM for mature caryopses and at 5 μM for leaf explants in combination with 22.5 μM 2,4-D produced high frequency plantlet regeneration by both organogenesis and somatic embryogenesis. The mode of regeneration was documented by light and scanning electron microscopy [...]
TL;DR: Experimental evidence was obtained to support previous reports that STN is a calcium related physiological disorder aggravated by low vapour pressure deficits inside in vitro culture vessels.
Abstract: SummaryEfforts were made to reduce the incidence of shoot-tip necrosis (STN), a frequent and persistent problem in shoot cultures of Pistacia, by supplementation of a standard Murashige and Skoog (1962) medium with raised levels of either boron or calcium. Experimental evidence was obtained to support previous reports that STN is a calcium related physiological disorder aggravated by low vapour pressure deficits inside in vitro culture vessels. Supplementation of liquid culture media with either 100–1000 µM boron or raised levels of calcium as calcium gluconate (0.3−30 mM) significantly reduced the development of STN symptoms supported on filter paper bridges but did not prevent STN. A practical solution to preventing STN in Pistacia vera cv. Mateur shoot cultures, derived from four year old mother trees, was developed subsequently whereby periodic inversion of culture tubes (once every 7 d) containing a liquid modified MS medium (Murashige and Skoog, 1962) supplemented with 15 mM calcium gluconate comple...
TL;DR: A procedure to regenerate shoots and bulbs in vitro with high frequency from shoot tips of garlic and shallot plants using benzyladenine or thidiazuron could be useful to produce low-cost bulbs, which are easy to handle and store until needed.
Abstract: A procedure is described to regenerate shoots and bulbs in vitro with high frequency from shoot tips of garlic and shallot plants using benzyladenine or thidiazuron. Regenerated shoots were induced to form bulbs in Murashige and Skoog medium (1962) containing 5 g l-1 activated charcoal and 120 g l-1 sucrose under a long-day photoperiod. Bulbs formed in vitro were transferred to soil without acclimatization and produced viable plants. This method could be useful to produce low-cost bulbs, which are easy to handle and store until needed.
TL;DR: Plant regeneration from protoplasts of Lilium × formolongi cv was achieved by utilizing suspension cultures of meristematic nodular cell clumps with a high plant regeneration ability and produced flowers with normal fertile pollen 8 months after successful transfer into soil.
TL;DR: A protocol for whole plant regeneration of Cicer arietinum L. cv.
Abstract: A protocol for whole plant regeneration of Cicer arietinum L. cv. C-235 via organogenesis from callus has been developed. Callus initiation was best when immature leaflets were cultured on MS medium containing 5 or 25 μM 2,4-D or NAA in combination with 10 μM BA, or 25 μM 2,4-D alone. The callus grew most vigorously on MS medum supplemented with 10 μM NAA and 5 μMBA. Best shoot differentiation was obtained from calli derived from the basal portion of shoot tips on MS medium supplemented with 10 μM BA and 0.1 μM IBA. The shoot forming ability of calli was enhanced by adding 5 mM potassium phosphate to the medium. Shoots were rooted on a MS medium containing l μM IBA. The regenerated plants were grown to maturity and produced viable seed.
TL;DR: An efficient protocol has been developed for inducing direct somatic embryogenesis from mature embryo axes in chickpea and Histological sections confirmed the direct origin of embryos from the explant.
TL;DR: The result showed that OT of Cymbidium PLB has ability to produce PLB directly from explants through organogenesis and suggests that exogenous hormones have no fundamental effects on PLB formation.
Abstract: Outer tissue (OT) excised from protocorm-like bodies (PLB) of Cymbidium×Thanksgiving, cultivar 'Nativity' produced PLB on hormone-free Murashige and Skoog (MS) medium and MS media supplemented with hormones. The PLB initiation from OT was earlier on hormone supplemented media compared to hormone-free MS medium. Explants showed the highest PLB formation abilitiy on the medium supplemented with 0.1 mg • liter-1 α- naphthaleneacetic acid (NAA) and 0.5 mg • liter-1 benzyl adenine (BA). On the medium of this combination, rate of cell division was high and the cell division occurred from surface to deeper tissue in the protuberance (an initial structure of PLB formed on OT explants) after 14 days of culture. OT explants turned light brown after 7 days of culture and a gray transparent protuberance was observed on the outer surface of the ex- plant after 14 days of culture. The protuberance gradually increased in size and turned into a green globular PLB after 21 days of culture. This pattern of PLB formation was similar in both hormone supplemented MS media and hormone-free MS medium. Thus it suggests that exogenous hormones have no fundamental effects on PLB formation. OT-de- rived PLB formed 100% shoot on the medium supplemented with 0.1 mg • liter-1 NAA and 1.0 mg • liter-1 BA within 8 weeks, but shoot formation was markedly suppressed on the media supplemented with NAA alone.Histological study showed that OT segments consisted of epidermal and sub-epidermal cells, which were parenchymatous, large and vacuolated. After one week culture, all the cells of epidermis were ruptured. A small group of cells with dense cytoplasm and deeply stained nuclei was observed just below the ruptured epidermis. These cells developed into a PLB. This result showed that OT of Cymbidium PLB has ability to produce PLB directly from explants through organogenesis.
TL;DR: Multiple shoots were obtained from shoot tips derived from mature plants (5 to 6 years old) of Citrus reticulata Blanco CV.f.
Abstract: Multiple shoots were obtained from shoot tips (2 to 3 mm) derived from mature plants (5 to 6 years old) of Citrus reticulata Blanco CV. Khasi mandarin and C. limon Burm.f. CV. Assam lemon when cultured on Murashige and Skoog (MS) medium, supplemented with (mg·liter -1 ) 1.0 BAP, 0.5 kinetin, and 0.5 NAA. Root induction was observed when 7-week-old single shoots (≈ 2 cm long) of both Citrus species were cultured on MS medium supplemented with (mg·liter -1 ) 0.25 BAP, 0.5 NAA, and 0.5 IBA. These plantlets were successfully established in the soil. Chemical names used: naphthalene acetic acid (NAA), indole 3-butyric acid (IBA), and benzylamino purine (BAP). plants from the orchard of the Assam Agricul- tural Univ., Jorhat. The expanded leaves were removed and washed thoroughly with a 1% solution of the detergent Teepol (Sigma, St. Louis) and then washed thoroughly with dis- tilled water. Explants were surface-sterilized with 2% (w/v) calcium hypochlorite solution
TL;DR: Latent infections of tissue-cultured Anthurium andraeanum Lind.
Abstract: Latent infections of tissue-cultured Anthurium andraeanum Lind. caused by the blight pathogen, Xanthomonas campestris pv. dieffenbachiae (McCulloch & Pirone) Dye, were examined. The pathogen survived in or on callus for over 4 months without producing symptoms in callus or turbidity in the medium. The pathogen survived for more than 1 year on or within stage II shoots without producing symptoms and was successively transferred three times as latently infected shoots were multiplied. The pathogen did not grow or survive for more than 2 weeks in Murashige and Skoog medium lacking plant material. The addition of coconut water enhanced bacterial growth and produced turbidity in culture media. Latently infected in vitro anthuriums may be inoculum sources for subsequent outbreaks of the disease.
TL;DR: A complete protocol for micropropagation of an adult tree Wrightia tomentosa is described, where multiple shoots were induced in vitro from nodal shoot segments through forced axillary branching to initiate a new culture cycle.
TL;DR: Explants from productive donor plants should be placed on DKW medium supplemented with TDZ to improve shoot regeneration efficiency from American elm leaves.
Abstract: Cytokinins, donor plants and their time in vitro as well as basal media were investigated for their influence on shoot regenerative capacity of American elm (Ulmus americana L.) leaves. Leaves excised from six 2-year-old seedlings formed adventitious shoots when placed on Driver and Kuniyuki Walnut (DKW) medium supplemented with 7.5, 15 or 22.5 μM of benzyladenine (BA) or thidiazuron (TDZ). Thidiazuron induced significantly higher regeneration percentages on elm leaves than BA, regardless of concentration used. Donor plant also affected the efficiency of shoot regeneration, with certain seedlings having 1.5 to 7 times more explants forming shoots as compared to other seedlings tested. By subculture 15, the average number of shoots per regenerating explant increased at least 3-fold for leaves on media with BA or TDZ for the one donor plant that survived continued subculturing. Leaf explants from donor plants with the highest regenerative capacity had a higher percentage of shoot formation on DKW than MS medium. Explants from productive donor plants should be placed on DKW medium supplemented with TDZ to improve shoot regeneration efficiency from American elm leaves.
TL;DR: Explants from the apical meristem of the same seeds produced fewer or no tetraploid plants, and sections from immature cotyledons of three genotypes produced higher frequencies of tetraPLoids than whole mature cotYledons or whole immature cOTyledon sections.
Abstract: pollen Abstract. Adventitious and axillary shoots of melon (Cucumis melo L.) were cultured from explants on a modified Murashige and Skoog medium containing 10 µM BA. Explants were diversified with regard to genetic source (breeding lines Miniloup, L-14, and B-line), seed parts (apical and cotyledon tissue), seed maturity (10-40 days after pollination; DAP), and cotyledon sections with respect to apical-radicle axis (distal and proximal). Plants were screened for ploidy level by pollen morphometry. Immature cotyledons produced more tetraploid regenerants than mature cotyledons from seed of breeding line Miniloup; the highest frequency of tetraploid regenerant plants was from cotyledons of embryos harvested 18 and 22 DAP. Explants from the apical meristem of the same seeds produced fewer or no tetraploid plants. Proximal sections from immature cotyledons of three genotypes (Miniloup, L-14, B-line) produced higher frequencies of tetraploids than whole mature cotyledons or whole immature cotyledons.
TL;DR: Static liquid half-strength Murashige and Skoog medium allows either somatic embryogenesis or shoot organogenesis along the borders of leaf incisions of a Cichorium hybrid to promote the development of callus and shoots at 20 °C and 25 °C instead of direct somatic embryos at 35 °C.
Abstract: Static liquid half-strength Murashige and Skoog medium, containing 10.1 mM KCl instead of KNO 3 , 1.7 mM glutamine, microelements, vitamins, 60 mM sucrose, 0.1 μM α-naphthaleneacetic acid and 2.5 μM 2-isopentenyladenine allows either somatic embryogenesis or shoot organogenesis along the borders of leaf incisions of a Cichorium hybrid (Cichorium intybus L. x Cichorium endivia L.). These phenomena are temperature-dependent and the latter promotes the development of callus and shoots at 20 °C and 25 °C instead of direct somatic embryogenesis at 35 °C. At 30 °C all types of morphogenesis are observed. After 5 d of culture, cells grown at each temperature exhibit enlarged nuclei with prominent nucleoli, fragmented vacuoles and dense cytoplasm. However, at 25 °C, callose is restricted to wounded cells whereas at 35 °C some nearby mesophyll cells show a more or less complete callose sheath. On the 7th day, proembryos at 35 °C show a superficial network which is absent at 25 °C on shoot primordia which are covered with a smooth precocious protoderm. Why do activated cells undergo segmentation and somatic embryogenesis at 35 °C instead of ordinary mitosis with callus and shoot formation at 20 °C and 25 °C?
TL;DR: The isozymes of esterase, peroxidase, glutamate oxaloacetate transaminase and acid phosphatase investigated in this study were found appropriate to distinguish compact embryogenic from friable non-embryogenic callus in sweet potato.
Abstract: The potential of somatic embryogenesis was evaluated for 10 cultivars of sweet potato through extensive embryogenic response and isozyme analysis. Embryogenic callus was induced by incubating lateral buds on Murashige and Skoog medium containing 10 μM 2,4-dichlorophenoxyacetic acid for 6–8 weeks. The frequency of embryogenic response was low, and varied with genotypes, ranging from 0 to 17%. Embryo to plantlet formation could be enhanced by the use of the combination of 2,4-dichlorophenoxyacetic acid with kinetin, both used at 0.01 μM. Embryogenic callus with its potential of plantlet formation has constantly been maintained for over two years. However, after several subcultures, 0.5 to 12% of embryogenic callus reverted irreversibly into friable fast-growing non-embryogenic callus whose ability to regenerate shoots was then definitively lost. The isozymes of esterase, peroxidase, glutamate oxaloacetate transaminase and acid phosphatase investigated in this study were found appropriate to distinguish compact embryogenic from friable non-embryogenic callus in sweet potato. In fact, the callus reversion was associated with a loss of bands or a decline in isozyme activity. On the contrary, very small changes in isozyme activity or no specific changes at all were observed during the differentiation of embryogenic callus into globular embryos.
TL;DR: It was found that phosphate was a key nutrient involved in pigment accumulation in the hairy roots, and that higher pigment contents in the roots were obtained at lower phosphate concentrations (range of 0–2.5 mol/m3).
Journal Article•
TL;DR: A study on the effect of genotype and culture medium on callus induced in seed explants of ten rice cultivars indicated significant variances due to genotypes, media and genotype x medium interactions (except callus induction frequency) for eight characters related to callusing and plant regeneration.
Abstract: A study on the effect of genotype and culture medium on callus induced in seed explants of ten rice cultivars indicated significant variances due to genotypes, media and genotype x medium interactions (except callus induction frequency) for eight characters related to callusing and plant regeneration. Among the genotypes, Pusa Basmati 1 gave the best overall callusing response. For plantlet regeneration, variety Pant Dhan 4 recorded the highest number of green spots and shoots while Sarju 52 had the highest potential for the length of longest shoot and rooting. Likewise the MS medium supplemented with 2.0 mgl−1, 2,4-D for callusing and 2.0 mgl−1 IAA plus 3.0 mgl−1 KN (MS (3)) for shooting while 3.0 mgl−1 IAA plus 4.0 mgr 1 KN (MS (4)) for rooting gave the best results. Some of the selected combinations like Pant Ohan 4 on MS medium supplemented with 2.0 mgl−1 2,4-D plus 1.0 mgl−1 KN displayed excellent callusing capacity while Pant Ohan 4 on MS (3) and MS (4), Sarju 52 on MS (4) and Pusa Basmati 14.0 mgl−1 lAA plus 4.0 mgl−1 KN (MS (5)) exhibited best regeneration capacity, and therefore, of fer good scope for high totipotency using appropriate genotype and media with propercombination of hormones.
TL;DR: In this article, the growth and pigment formation of madder hairy roots were significantly enhanced by using modified Murashige-Skoog (MS) medium containing fructose and nitrate as the sole carbon and nitrogen sources, respectively.