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The concept of using sunlight for micropropagation systems is proposed as a way of reducing tissue culture costs. Shoot tips
of Musa acuminata cultivar ‘Grande Naine’ were cultured in a non-controlled natural light environment at the IAEA Laboratories,
Austria during summertime. Significantly more shoots were produced by plantlets cultivated in a sunlit room with photosynthetic
photon flux densities (PPFD) fluctuating up to 570 μmol m-2 s-1, temperatures between 23 and 30 °C and photoperiods of 12
to 16-h, than by plantlets under artificial light in a growth chamber providing controlled conditions of a constant PPFD of
65 μmol m-2 s-1, temperatures ranging from 23 to 29 °C and a 16-h photoperiod. Highest multiplication rates were achieved
in a greenhouse with PPFD reaching 860 μmol m-2 s-1 and temperatures of 18 – 43 °C, but browning of leaves and loss of turgor
occurred. Nevertheless, rooted plantlets showed 100% survival during acclimatisation and normal development. Photoperiods
of 12 – 16 h did not affect the multiplication rates.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
2.
F. J. Zapata-Arias L. B. Torrizo A. Ando 《World journal of microbiology & biotechnology》1995,11(4):393-399
As the World's population is expanding rapidly, all possible techniques for crop improvement must be utilized to meet the food demands of the next century. Although conventional breeding techniques have considerably increased the productivity of modern crops, the application of advanced molecular technologies could speed up further crop improvement. Use of biotechnology, such as the various tissue-culture methods and gene-transfer techniques now available, could significantly shorten the breeding process, and overcome some of the substantial agronomic and environmental problems that have not been solved using conventional methods. The present review discusses biotechnological developments in the genetic improvement of rice, the principal food for more than a third of the World's population.F.J. Zapata-Arias is with the Plant Breeding Unit, FAO/IAEA Agriculture and Biotechnology Laboratory, A-2444 Seibersdorf, Austria; L. B. Torrizo is with the Plant Breeding, Genetics and Biochemistry Division. The International Rice Research Institute. P.O. Box 933, 1099 Manila, Philippines. A. Ando is with the Universidade de Sao Paulo, Campus Luiz de Queiroz, Departamento de Genetica, C.P. 83, 13400 Piracicaba, Sao Paulo, Brazil. 相似文献
3.
Histology of somatic embryo initiation and organogenesis from rhizome explants of Musa spp. 总被引:1,自引:0,他引:1
The origin of somatic embryos derived from rhizome explants of triploid Musa cv. Grand Nain was the subject of histological
studies during different phases of ontogenetic development. The investigation revealed that the majority of somatic embryos
showed normal root formation and consisted of highly vacuolated cells in the poorly structured shoot apex. The embryogenic
mass and somatic embryos were mostly derived from several morphologically competent cells. Single cell origin depended on
the presence of organogenetically functional vascular cells of rhizome explants and occurred infrequently. The implications
of these findings for genetic improvement of banana and plantain by in vitro mutation breeding and gene technology are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
4.
Flow cytometric analysis of nuclear genome of the Ethiopian cereal tef [Eragrostis tef (Zucc.) Trotter] 总被引:1,自引:0,他引:1
Flow cytometric analysis of nuclear DNA content was performed by using nuclei isolated from young leaf tissue of tef (Eragrostis tef). The method was very useful for rapid screening of ploidy levels in cultivars and lines of tef representing the phenotypic variability of this species in Ethiopia. The results of the analysis showed that all cultivars were tetraploid. Flow cytometry was also used to determine nuclear DNA content in absolute units (genome size) in four tef cultivars. Nuclei isolated from tomato (Lycopersicon esculentum, 2C=1.96 pg) were used as an internal reference standard. The 2C DNA content of individual tef cultivars ranged from 1.48 to 1.52 pg (1C genome size: 714 Mbp-733 Mbp), the differences among them being statistically nonsignificant. The fact that the nuclear genome of tef is only about 50% larger than that of rice should make it amenable for analysis and mapping at the molecular level. 相似文献
5.
Rapid detection of aneuploidy in <Emphasis Type="Italic">Musa</Emphasis> using flow cytometry 总被引:3,自引:0,他引:3
We report a procedure for the rapid and convenient detection of aneuploidy in triploid Musa using DNA flow cytometry. From a population of plants derived from gamma-irradiated shoot tips, plants were selected based on aberrant morphology and their chromosome numbers were counted. Aneuploids plants with chromosome numbers 2n=31 or 32 were found as well as the expected triploid plants (2n=3x=33). At the same time, the nuclear DNA content of all plants was measured using flow cytometry. The flow cytometric assay involved the use of nuclei isolated from chicken red blood cells (CRBC), which served as an internal reference standard. The relative DNA content of individual plants was expressed as a ratio of DNA content of CRBC and Musa (DNA index). In order to estimate the chromosome number using flow cytometry, the relative DNA content of plants with unknown ploidy was expressed as a percentage of the DNA content of triploid plants. The classification based on flow cytometry fully agreed with the results obtained by chromosome counting. The results indicated that flow cytometry is a convenient and rapid method for the detection of aneuploidy in Musa. 相似文献
6.
Andrea Kodym Stefan Hollenthoner Francisco Javier Zapata-Arias 《In vitro cellular & developmental biology. Plant》2001,37(2):237-242
Summary Daylight instead of artificial light was exploited for the in vitro culture of banana. Tubular skylights rediverted natural light into an interior enelosed room whereby each skylight, available
for ca. US$600, could sufficiently illuminate an area of 3–5 m2. The maintenance-free system allowed only a minimum of heat transfer and no cooling was necessary. The culture room required
no electricity supply and under our conditions savings on costs for electricity of US$6 m−2 wk−1 were achieved, as compared to a standard growth room equipped with artificial lighting and controlled photoperiod and temperature
regimes. Under natural light conditions, micropropagated plantlets were well developed at mean photosynthetic photon flux
densities (PPFD) of 5–13 μmol m−2 s−1 and photoperiods of 9–14 h. Micropropagation rates were either the same or significantly higher than under artificial lighting.
Single shoots on rooting medium showed some symptoms of etiolation, yet acclimatization rates averaged 95%. A step-like culture
rack. rather than a vertical one, permitted uniform plant growth on all levels. This paper describes an established micropropagation
system of low cost and simplicity. 相似文献
7.
Low-cost alternatives for the micropropagation of banana 总被引:3,自引:0,他引:3
A 90% resource cost reduction in tissue culture of banana was achieved by replacing tissue culture grade sucrose and Gelrite
in the medium with locally available commercial sugar and a starch/Gelrite mixture and by using sun light instead of artificial
light. The micropropagation of Musa `Grande Naine' by shoot tip culture was used as model. Thirteen commercial sugars from different countries were tested. Best
results were achieved using white and light brown sugars with low electrical conductivity. Sugars of cane or sugar beet origin
were suitable. Starches of corn or potato could partially substitute for Gelrite and agar. In all experiments, micropropagation
rates under natural light conditions were equal to or higher than under the controlled conditions of a growth room with PPFD
of 65 μmol m−2 s−1 and a 16-h photoperiod. Plants were exposed to average PPFD levels of 58–96 μmol m−2 s−1 and photoperiods ranged from 8–16 hours.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
8.
Roux Nicolas Dolezel Jaroslav Swennen Rony Zapata-Arias Fransisco J. 《Plant Cell, Tissue and Organ Culture》2001,66(3):189-197
In vitro mutagenesis of multicellular meristems of Musa spp. leads to a high degree of chimerism. Repeated vegetative propagation must be carried out to dissociate chimeras but
the minimum number of cycles required is unknown. In general, mutated cells are difficult to monitor but mutations which result
in a change in genome number are an exception. We simulated this case by colchicine treatment, followed by flow cytometric
analysis. Colchicine treatment induced ploidy chimerism (mixoploidy), and chimera dissociation was assessed using three different
propagation systems (shoot-tip culture technique - ST, multi-apexing culture technique - MA and corm slice culture technique
- CS). The average percentage of cytochimeras was reduced from 100% to 36% after three subcultures using shoot-tip culture,
from 100% to 24% when propagating by the corm slice culture technique and from 100% to 8% after the same number of subcultures
using the multi-apexing technique. All propagation systems failed to eliminate chimerism completely. Factors that may influence
chimera dissociation in vitro are discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
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