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Protoplasts were isolated from mesophyll of axenic cultures of grape, Vitis rotundifolia cv. Summit and V. vinifera cv. Cabernet Sauvignon. Enzymes effective for protoplast isolation were Macerozyme R-10 (0.5% and 0.1%) and Cellulase Onozuka R-10 (1.0% and 0.5%) for V. rotundifolia and V. vinifera, respectively. Polyvinylpyrrolidone and 2-(N-morpholino)ethanesulfonic acid were essential in the isolation media. Protoplasts were purified using flotation/centrifugation. The protoplasts of V. rotundifolia cultured in Gamborg's B5 basal medium with 2.2 M 6-benzyladenine, 4.5 M 2,4-dichlorophenoxyacetic acid and 0.4% agarose gave the best plating efficiency of conditions tried in this study. Cell division occurred within 5 to 6 days and visible microcalli developed within one month. After 6 weeks in culture, microcalli transferred to liquid medium exhibited active callus growth. Protoplasts of V. vinifera cultured under these conditions had similar results.Abbreviations MES
2-(N-morpholino)ethanesulfonic acid monohydrate
- PVP
polyvinylpyrrolidone
- PDS
potassium dextran sulfate
- BA
6-benzyladenine
- 2,4-D
2,4-dichlorophenoxyacetic acid
- FDA
fluorescein diacetate 相似文献
5.
Jeffrey R. Hazel Rochelle Carpenter 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1985,155(5):597-602
Summary The phospholipid composition of gill tissue was determined in rainbow trout (Salmo gairdneri) undergoing thermal acclimation between 5°C and 20°C for a period of up to 28 days. Proportions of phosphatidylethanolamine
(PE) and cardiolipin (CL) increased during cold acclimation and decreased during warm acclimation; proportions of phosphatidylcholine
(PC) changed in the opposite direction (i.e., decreased during cold acclimation). In contrast, levels of phosphatidylserine,-inositol,
and sphingomyelin did not vary significantly. Thermal modulation of headgroup composition occurred rapidly as reflected by
changes in the ratio of PC-to-PE, which rose significantly from 2.40±0.09 to 2.92±0.09 within 72 h of transfer from 5 to 20°C;
adaptation to 5°C was equally rapid. Proportions of PE changed more rapidly than those of PC during cold adaptation, whereas
the opposite was true during warm acclimation. Both the time course and the direction of the observed changes in phospholipid
composition suggest that such adjustments may contribute to the homeoviscous regulation of membrane properties, particularly
during the initial stages of thermal adaptation. 相似文献
6.
Structure and transcription of eukaryotic tRNA genes 总被引:45,自引:0,他引:45
7.
Calculations are reported of the time-dependent Nernst-Planck equations for a thin permeable membrane between electrolytic solutions. Charge neutrality is assumed for the time-dependent case. The response of such a membrane system to step current input is measured in terms of the time and space changes in concentration, electrical potential, and effective conductance. The report also includes discussion of boundary effects that occur when charge neutrality does not hold in the steady-state case. 相似文献
8.
A mass in the neck, facial pain and cranial nerve palsies are the most common presenting symptoms of malignant tumours of the nasopharynx. Surgery is limited to biopsy for histological diagnosis. External irradiation is the treatment of choice, both for the primary lesion and the regional and distant metastases. Illustrative case histories are presented in detail. Experience over a 20-year period demonstrates that a 20% five-year survival rate has been obtained. 相似文献
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J. Austin Burns Hazel Y. Wetzstein 《In vitro cellular & developmental biology. Plant》1995,31(2):72-78
Aggregates of globular and pre-globular stage somatic embryos from suspension cultures of pecan (Carya illinoensis Koch) were cultured on solidified media for embryo development. Embryo aggregates and pre-globular stage embryo masses were
given various treatments to further ontologic development. A 2- to 4-wk mild dehydration of the embryo aggregates suppressed
recurrent embryogenesis, promoted development of globular embryos into cotyledonary stage embryos, and enhanced plant development
beyond germination. Fine embryogenic tissue masses filtered from suspension formed cotyledonary-staged embryos when the collection
filters were plated on solified medium. The embryogenic capacity of preglobular stage embryo masses was compared between media
supplemented with varying concentrations of polyethylene glycol (molecular weight 8 000) vs. filter overlays. The filter paper
overlays were not necessary for embryo development. An inverse relationship was found between the number of embryos that developed
and the concentration of polyethylene glycol in the medium. However, this relationship was reversed for ability of embryos
to germinate and develop into a plant. 相似文献