0000000000046686
AUTHOR
J. B. Amo-marco
In vitro propagation ofSalix tarraconensis Pau ex Font Quer, an endemic and threatened plant
Salix tarraconensis Pau ex Font Quer, an endemic willow species from northeast Spain, was micropropagated with nodal segments. Shoot multiplication was obtained with different cytokinins, either on Murashige and Skoog medium or woody plant medium. Best results for shoot formation were obtained on Murashige and Skoog medium containing 4.9 μM of 6-γ-γ-dimethylallylaminopurine. Shoots showed strong apical dominance, and some cultures displayed apical necrosis. Benzyladenine gave the worst results; shoots displayed very slow growth, deformed leaves, and hyperhydrity. Good rooting of shoots was obtained with different auxins or without plant growth regulators on woody plant medium. The best resu…
EFFECT OF PLANT GROWTH REGULATORS AND ORANGE JUICE ON GROWTH OF CALLUS FROM FRUIT TISSUES OF WASHINGTON NAVEL ORANGE
The effect of the plant growth regulators kinetin, gibberellic acid (GA3), and 2,4- dichlorophenoxyacetic acid (2,4-D), either alone or in combination with orange juice, on the in vitro growth of mesocarp and endocarp explants from 90–120 day-old Washington Navel Citrus sinensis orange fruits has been determined. Both fruit tissues formed callus. From endocarp 100% callus was formed in all cultures, even without growth regulators in the culture medium, while callus growth was lower from mesocarp. The addition of orange juice at a final concentration of 15% (v/v) to the basal medium without growth regulators increased the callus growth, specially that derived from endocarp. However, the high…
Effect of plant growth regulators and basal media onin vitro shoot proliferation and rooting ofMyrtus communis L.
The influence of macronutrients and growth regulators on in vitro shoot proliferation and rooting of an East Spanish population ofMyrtus communis L. were studied. Preincubation of field material on a medium without mineral salts prevented the browning from phenolic exudates. For multiplication, nodal segments of 5 mm fromin vitro produced shoots were cultured on Murashige and Skoog (MS), Schenk and Hildebrandt (SH) and Heller (H) media (full strength or diluted to 1/2 or 1/4), with 6-benzylaminopurine (BAP) at concentrations 4.4, 13.3 and 22.2 ΜM or kinetin (K) at concentrations 4.7, 14.0 and 23.2 ΜM. The optimum shoot proliferation was on quarter-strength MS medium with 4.4 ΜM BAP, whereas…
Factors affectingin vitro shoot proliferation ofMyrtus communis L.: A comparison of adult and seedling material
Two stocks of shoots growingin vitro, obtained from either seedlings or adult plants, were used to study the effects of material origin, the number of previous subcultures on the establishment medium, the explant type, and the macronutrients on shoot multiplication and elongation inMyrtus communis L., always in the presence of 4.4. μM benzyladenine (BA). Shoot proliferation was influenced mainly by stock origin, with higher responses from the adult material than from the seedling material, and by the number of subcultures, with the largest rates of multiplication and elongation in the first subculture. In the first subculture, the adult material was characterized by high rates of shoot mult…
Secondary somatic embryogenesis and plant regeneration in myrtle (Myrtus communis L.).
Immature seeds, as well as hypocotyls and cotyledons excised from seedlings of Myrtus communis L., were cultured on media containing half-strength Murashige and Skoog macronutrients (MS/2) with combinations of auxins and cytokinins, in order to study their morphogenetic competence. Somatic embryogenesis was obtained from cotyledons, hypocotyls and 2-month-old immature seeds with 0.1 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D). The percentage of explants showing this primary somatic embryogenesis ranged from 4% for hypocotyls to 12% for 2-month-old immature seeds. In the latter, somatic embryogenesis was also obtained in media containing 2,4-D plus a cytokinin, and with only a cytokinin. Som…
THE ROLE OF CYTOKININS AND ETHYLENE INHIBITORS ON LENTICEL HYPERTROPHY GENERATION AND ETHYLENE PRODUCTION IN IN VITRO CULTURES OF POPULUS EUPHRATICA OLIVIER
Populus euphratica Olivier is native to the Irano—Turanian areas (Middle East). Elche (Alicante province, SE Spain) is known to be its only European location. Nodal segments from root shoots were established in vitro in a Murashige and Skoog medium supplemented with several cytokinins. Ethylene inhibitors AgNO3 and CoCl2 were used in combination with kinetin. Hormone-free media supplemented with sucrose (20–60 mg 1−1) was also tested. Ethylene was measured by gas chromatography, and both the percentage of sprouting shoots and lenticel hypertrophy in cultures were recorded. Ethylene production was higher in cultures supplemented with cytokinins (especially with meta-topolin), with high sprou…
In vitro multiplication ofVella lucentina M. B. crespo (Brassicaceae), a threatened Spanish endemic species
Vella lucentina M. B. Crespo is a threatened Spanish species that is endemic to a small area in eastern Alicante Province (SE Spain). Micropropagation techniques were applied forex situ conservation of this plant. Aseptic epicotyls bearing the apical bud were grown in Murashige and Skoog medium supplemented with 6-furfurylaminopurine (Kin), N6-benzyladenine (BA) or 6-(γ,γ,-dimethilalylamino) purine (2iP). High multiplication rates were obtained with 0.5, 1, or 2 mg·liter−1 BA, or 1 or 2 mg·liter−1 2iP. Indole-3-acetic acid and indole-3-butyric acid were utilized for rooting in half-strength Murashige and Skoog medium. Regenerated plants were transferred to a potting mix and gradually acclim…
Foreed flushing of branch segments as a method for obtaining reactive explants of mature Quercus robur trees for micropropagation
The aim of this study was to micropropagate mature Quercus robur L. trees when material retaining physiologically juvenile characteristics (stump sprouts, epicormic shoots) is not available. Branch segments from 70–300 year-old trees were force-flushed and the flushed, partially rejuvenated or reinvigorated shoots were used as a source of explants for establishment of cultures. In vitro establishment and multiplication was achieved with seven of the eight selected trees. The proliferation capacity of cultures of vertically placed explants declined after several subcultures, but efficient shoot multiplication was achieved by culturing decapitated shoots placed horizontally on GD medium suppl…
Micropropagation from inflorescence stems of the Spanish endemic plant Centaurea paui Loscos ex Willk. (Compositae)
Tissue culture techniques have been established as a useful approach for ex situ conservation of rare, endemic or threatened plant species. This report describes the micropropagation of Centaurea paui Loscos ex Willk (Compositae), an extremely endangered plant species endemic to the Valencia Community (eastern Spain), as a conservation measure which does not cause damage to the wild plants used as explant source. Inflorescence nodal segments of C. paui were selected as explants for in vitro establishment. The best rate of shoot proliferation was obtained on Murashige and Skoog (MS) mineral medium supplemented with 0.5 mg/l 6-benzyladenine or with 2 mg/l kinetin. Maximum shoot elongation was…
Polypeptide Markers Differentiating Juvenile and Adult Tissues in Chestnut
Differences were observed between the polypeptide contents of in vitro shoot cultures derived from upper branches (adult material) and basal shoots (juvenile material) of the same chestnut tree. Cultures derived from mature crown growth yielded two polypeptide bands that were not afforded by cultures derived from juvenile basal shoots. Since all cultures were derived from the same tree the polypeptide differences appear to reflect the ontogenetic age of the starting material.