Search results for "Callu"
showing 10 items of 70 documents
Stimulation of root and somatic embryo production in Euconymus europaeus L. by an inhibitor of polyamine biosynthesis
1995
In vitro formation of roots and somatic embryos is obtained from cotyledon explants of a Spindle tree (Euonymus europaeus L.) cultured on two different media: a medium inducing callus formation and the production of roots, and a medium inducing callus formation, root and somatic embryo production. We studied the effects of α-difluoromethylornithine (DFMO), a specific, irreversible inhibitor of ornithine decarboxylase (ODC) on root and somatic embryo production, growth and titers of putrescine in Euonymus explants and explant-derived calli. Early changes in putrescine levels were detected in both cultures before the visible emergence of roots or somatic embryos. DFMO rapidly inhibited putres…
In vitro biotechnology approaches now available for ‘beautiful’ vavilovia (Vavilovia formosa)
2014
BAP Pôle GEAPSI; Efficient in vitro propagation of Vavilovia formosa, plant regeneration from callus, protoplast isolation and culture to differentiated callus of V.formosa were developed and its relative nuclear DNA content by flow cytometry was established. The summation of biotechnology tools now available should foster evolutionary studies on the tribe Fabeae and, intime, V.formosa could be come a potential source of novel agronomic adaptive traits.
Somatic embryogenesis from hypocotyl callus cultures of Digitalis obscura L.
1986
Hypocotyl-derived calli obtained in agar solidified medium with several growth regulator combinations gave rise to proembryonal masses and globular embryos when transferred to liquid media with lower growth regulator and higher NH4HO3 levels. By transferring cultures from liquid media to different solidified media, new embryo formation took place, but further development of these embryos or those previously induced depended on the characteristics of these media. Normal development was only achieved on 8 g/l agar solidified medium without growth regulators. Typical cotyledonary embryos developed into whole plants when transferred to this same medium.
The ambiguous role of 2,4-dichlorophenoxyacetic acid in wheat tissue culture
1986
The very basal, highly immature regions of dissected young leaves of Triticum aestivum L. cv. Kite formed adventitious roots on a nutrient medium supplemented with comparatively low concentrations (0.16 to 0.63 μM) of 2,4-dichlorophenoxyacetic acid (2,4-D). Higher concentrations (up to 640 μM) had to be applied to stimulate growth from more mature regions higher up the leaf. Yet, already at 2.5 μM roots were less distinct and more callus-like, and eventually (at 10 to 640 μM) only a subculturable callus of apparently suppressed, slowly proliferating root primordia developed. Furthermore, at the most basal, highly immature regions growth was significantly retarded when the auxin concentratio…
Eliciting callus culture for production of hepatoprotective flavonoids and phenolics from Sequoia sempervirens (D. Don Endl)
2020
The aim of our study is to estimate the hepatoprotective effects of the ethanolic extract of the leaves of Sequoia sempervirens by determination of liver biomarkers (ALT, AST, total bilirubin and albumin in serum) and by histopathological examinations using thioacetamide-induced (TAA) liver injury model. Concurrent administration of ethanolic extracts of S. sempervirens leaves improved the alterations in liver morphology where it was a potent protector of the liver. The potential of L-phenylalanine and silver nitrate as chemical elicitors as well as UV radiation as a physical elicitor on flavonoid production in callus culture of S. sempervirens were emphasized. Murashige and Skoog’s medium …
Secretion of Protein-bound Hydroxyproline from Moss Callus Cells
1988
Abstract A glycoprotein rich in hydroxyproline was found in wall preparations of callus cells of the moss Physcomitrium pyriforme Brid. It is apparently attached to the non-cellulosic polysaccharides of the wall, and the majority is extractable by boiling the wall fraction or by using a chaotropic salt at room temperature. A pulse-chase technique was used to study the transport of this protein to the wall. Cytochalasin B seems to inhibit its secretion from the callus cells. Some of this wall-associated protein is probably secreted from the cells into the medium. Electron microscopic evidence shows vesicular activity in the cytoplasm and secretion and incorporation into the wall layers (not …
Spermidine and morphogenesis in single cell cultures of Sideritis angustifolia lag.
1990
Abstract Single cells from hypocotyl-derived callus of Sideritis angustifolia were evaluated for morphogenesis when cultured in either solidifier or liquid Murashige and Skoog medium supplemented with various concentrations of spermidine, naphthaeneacetic acid (NAA), benzyladenine (BA) and dicyclohexylamine (DCHA). Spermidine (Spd) did not replace the hormonal requirements for cell division and callus formation, but affected growth induced by NAA or BA. This polyamine increased the plating efficiency of cells cultured in the presence of NAA (0.05, 0.54 and 5.40 μM) or BA (0.40, 4.40 and 8.80 μM). In contrast, Spd reduced growth induced by 10.80 μM NAA, optimal auxin concentration for callus…
Adventitious shoot regeneration from hypocotyl cultures of service tree(Sorbus domesticaL.)
1992
Effects of growth regulators and N03:NH4 ratio were investigated to determine the mor- phogenic capacity of hypocotyl explants of service tree (Sorbus domestica L.) Organogenic responses were preceded by an initial callus phase and depended mainly on the auxin type used. NAA induced root differentiation whereas IAA added to media containing BA promoted adventitious shoot regeneration. Best results were obtained with 2.5 μM each of BA and IAA (19% of caulogenic explants). This reponse was increased (up to 44%) by varying nitrate to ammonium ratio from 2:1 to 4:1.
Somatic embryogenesis and plant regeneration in a woody species: the European Spindle Tree (Euonymus europaeus L.).
1993
Somatic embryogenesis and subsequent plant regeneration of Euonymus europaeus L (European Spindle Tree) were obtained from square pieces of mature zygotic embryos with an intervening callus phase. Callus and somatic embryos were induced using a Murashige and Skoog's semi-solid basal medium supplemented with several combinations of auxins and cytokinins. The greatest number of somatic embryos was obtained with a continuous exposure to 22.8 μM indoleacetic acid and 0.046 μM kinetin. The frequency of somatic embryogenesis from zygotic embryos depends on the cold conservation time of seeds. The embryos frequently germinated on the same medium. Further development of somatic embryos into plantle…
Untersuchungen zur Biosynthese eines Cytokinins in Calluszellen von Laubmoossporophyten
1973
When callus cells derived from the sporogon of the hybrid Funaria hygrometrica x Physcomitrium piriforme are supplied with adenine-8-14C, they produce a labelled cytokinin which has the same chromatographic behavior as N6-γγ-(dimethylallyl)aminopurine. The cytokinin is the first radioactive product that can be detected in the culture medium. It is formed as long as labelled adenine is available. When callus cells are grown in an optimum culture medium containing amino acids, about 10% of the radioactivity supplied as adenine is found in the cytokinin. When the cells are grown in a medium without amino acids, the RNA-content of the cells and the total yield of cytokinin decrease, but about 1…