Search results for "Shoot"
showing 10 items of 298 documents
Morphogenic responsein vitroof epicotyl segments ofCitrus macrophylla
2008
Abstract The influence of explant orientation, contact of the cut surface with the medium, type of growth regulators and distance of epicotyl cuttings from the cotyledonary node (the part of the seedling where the cotyledons are attached) on in vitro morphogenesis of Citrus macrophylla (alemow) was evaluated. Maximum number of shoots was induced from epicotyl segments placed horizontally.
Micropropagation of Genista aetnensis [(Raf. ex Biv.)DC]
2015
Genista aetnensis [(Raf. ex Biv.)DC] is a large deciduous shrub or small tree native to the Italian islands of Sardinia and Sicily. Being winter hardy and characterized by high plasticity in altitude and ecology, the species is grown in gardens and landscaping, both for flower and for its attractive shape. Genista species are generally propagate by seed or semi hardwood cuttings. In this report an efficient in vitro technique for propagation of G. aetnensis was investigated. Multiple shoots were induced on nodal segments of a mature plant of Genista aetnensis . The Murashige and Skoog medium, augmented with different concentrations of benzyladenine either singly or in combination with indol…
Measurement of Photosynthesis and Transpiration in Spruce Trees with Various Degrees of Damage
1987
Summary In the context of a project on physiological and biochemical characterization of spruce with different degrees of damage, the C02 and H2O gas exchange of 22-year-old spruce from a location in the Hunsru.ck (West Germany) were measured in summer 1985. The measurements were carried out on shoots from 1984 and were set up as a pair comparison, i.e. the measurement data of a tree with symptoms of damage were always compared with a tree in the immediate vicinity which phenotypically showed less damage. Diurnal course measurements in the open air revealed a marked reduction of photosynthesis depending on the degree of damage of the trees. If one plots photosynthetic rate against light int…
Plant hormones and Agrobacterium tumefaciens strain 82.139 induce efficient plant regeneration in the cardenolide-producing plant Digitalis minor
2002
Summary Shoot formation in explants of Digitalis minor was achieved, through axillary bud proliferation and adventitious bud differentiation, by varying the amount and source of plant hormones. Shoot regeneration was also obtained after infection of D. minor with the wild-type Agrobacterium tumefaciens strain 82.139, which induced shooty tumours. These shoots were not transgenic, as revealed by nopaline assays and the use of a C58pMP90/T139GUS-INT strain harbouring the intron inactivated gusA gene. Plants were easily rooted and transplanted into the greenhouse. Shoot cultures of D. minor accumulated up to 226 μg cardenolides per g dry mass when cultured on agar-solidified medium. Cardenolid…
Plant regeneration from juvenile and adult Anthyllis cytisoides, a multipurpose leguminous shrub
1997
Summary Anthyllis cytisoides , a legume shrub used for afforestation and reclamation of degraded Mediterranean areas, was successfully micropropagated from expiants of juvenile (cotyledonary nodes and apical buds) and adult origin (axillary buds). Multiple shoot formation was dependent on the presence of benzyladenine in the induction medium. Of the salt formulation and expiants examined, the higher proliferation rates were obtained when axillary buds from adult plants were cultured on a modified Schenk and Hildebrandt medium. Following the preferred protocol, shoot yield reached values greater than 100 shoots per expiant. Plants were easily rooted and transplanted into greenhouse.
Effect of rootstock on trunk growth and foliar mineral content in cv. Bianca pistachio (Pistacia vera L.) trees
1998
Trunk cross-sectional area (TCSA) and mineral content were recorded for 4 years in the major Sicilian pistachio cultivar, Bianca, budded in 1991 onto eight in v/fro-propagated clonal rootstocks (Pistacia atlantica and P. integerrima) and one seedling rootstock (P. terebinthus). The trees were grown using standard cultural practices for Sicilian dry-land farming in a fine sandy soil, located inland in Sicily (20 km SW of Palermo, 350 m a.s.l.). From nine trees per rootstock, samples of 10 leaflets from the mid-section of current year shoots were taken yearly in August and analyzed for the main plant mineral elements (N, P, K, Ca, Mg, Fe, Mn, Zn, Cu and B). The TCSA was measured at the end of…
Stipa klimesii (Poaceae), a new species from Western Himalayas (India)
2014
Stipa klimesii sp. nov. from the Western Himalayas (India: Ladakh) and its variety S. klimesii var. pubescens var. nov. are described. The new species is similar to S. roborowskyi but differs by its longer anthecium, longer ligules of vegetative shoots, longer hairs on seta and shorter awns. Stipa klimesii is also similar to S. purpurea, but differs by longer ligules of vegetative shoots, shorter awns, slightly shorter hairs on seta and by the character of the panicle, which is compressed and with straight branches in S. klimesii vs. lax and with flexuous branches in S. purpurea. Epidermal patterns of the lemma in S. klimesii and both above-mentioned species, were examined by scanning elect…
Changes of morphogenic competence in mature Pinus sylvestris L. buds in vitro.
2002
The effects of season and cold storage on morphogenic competence in mature Pinus sylvestris buds were investigated. Peroxidase and polyphenol oxidase activity were measured as markers of oxidative metabolism. No growth in vitro was observed on explants detached from the end of January until the beginning of March. Brachioblasts, each with a couple of needles, formed on 11 % of the buds without macrostrobili that were detached in early April and introduced immediately into culture. Of the explants detached in late July, 15 % formed shoots with brachioblasts and needles. The lowest activity of peroxidase and polyphenol oxidase in pine buds was observed from the end of April until the beginnin…
Micropropagation of juvenile and adultDigitalis obscura and cardenolide content of clonally propagated plants
1991
Cultures ofDigitalis obscura L. were established from axillary buds of mature plants or leaves of seedlings obtained under aseptic conditions. Explants were cultured on Murashige and Skoog medium containing benzyladenine and/or naphthaleneacetic acid. Shoot proliferation from axillary buds was not affected by seasonal fluctuations in the stock plants and increased relative to the cytokinin concentration, but auxin reduced the multiplication rate. Differentiation of somatic embryos and adventitious buds from cultured leaves required naphthaleneacetic acid alone or combined with benzyladenine, respectively. Cardenolide pattern and content of the regenerated plants were determined by high perf…
Effect of CCC and pH on shoot elongation in Sedum rubrotinctum R.T. Clausen
2002
Sedum rubrotinctum plants grown during winter in a glasshouse had decreased leaf density and increased internode length as well as loss of red coloring, leading to diminished ornamental value. Treatment with growth retardant (2-chloroethyl)trimethyl ammonium chloride (CCC) reduced internode length as well as the number of internodes. Concomitant changes of ethylene production and peroxidase activity were found in CCC-treated plants. Substrate pH had a significant effect on the growth of S. rubrotinctum. This leads to the conclusion that increase of shoot growth during winter period could be reversed by means of growth retardant CCC and acidification of substrate.