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61.
The effect of triazine and carbamate type of anticytokinins on in vitro response of embryogenic and nonembryogenic genotypes of orchardgrass (Dactylis glomerata L.) was studied. Both compounds stimulated callus production. Anticytokinins influenced both the efficiency of somatic embryogenesis and frequency of embryoid formation. 相似文献
62.
KCN和NaN3预处理对烟草愈伤组织抗氰呼吸的影响 总被引:3,自引:0,他引:3
用0.5 m m ol/L KCN 或0.01 m m ol/L NaN3 预处理继代培养25 d 的“甘肃黄花烟草”(Nicotiana rustica L. cv. Gansu yellow flow er)愈伤组织对其呼吸作用有明显的影响。KCN 和NaN3 预处理12 h 可分别使愈伤组织的总呼吸速率下降12% 和17% ,细胞色素途径的实际运行量分别下降22% 和28% ;抗氰交替途径在最大容量(Valt)基本不变的情况下,实际运行量(ρ·Valt)不但未随总呼吸速率和细胞色素途径运行量的下降而降低,反而还略有上升。结果导致细胞色素途径对总呼吸的贡献下降而抗氰交替途径对总呼吸的贡献上升。KCN 预处理24 h,细胞色素途径的实际运行量虽略有回升,但仍低于对照;NaN3 预处理24 h 则使细胞色素途径运行继续下降而交替途径运行持续上升。上述结果表明,在继代培养的烟草愈伤组织中,当细胞色素主路途径被部分抑制后交替途径的电子流量明显加强,从而起着一种补偿作用 相似文献
63.
几种细胞分裂素诱导石竹外植体直接再分化成花芽的机理 总被引:4,自引:0,他引:4
用MS+2,4-D0.1mg/L为基本培养基,分别附加不同浓度的ZT、BA和KT,对石竹的叶片、茎和花等外植体直接再分化成花芽的试验表明:叶片的外植体在有BA时可再分化出只有红色花瓣的不正常花芽;在含ZT的培养基中再分化出具有1~2片叶或无叶的花芽,其花有两性花,雌花和仅单个雌蕊的不正常花,两性花可发育成结籽的果实;KT未能诱导花芽分化。茎外植体,3种CTK都不能诱导出花芽。花等外植体仅在KT3mg/L的培养中再分化出无叶的不正常花芽,ZT和BA的处理均不能诱导出花芽。 相似文献
64.
普通小麦×东方旱麦草属间杂种的产生及无性系的建立 总被引:3,自引:0,他引:3
本研究以普通小麦(TriticumaestivumL.;2n=6x=42,AABBDD)为母本,以东方旱麦草(Eremopyrumorientale(L.)Jaub.etSpach;2n=4x=28)为父本,首次成功地获得了属间远缘杂种F1,其平均结实率为0.08%。利用植物细胞工程技术,对杂种幼胚愈伤组织的诱导、胚性无性系的建立、植株再生、壮苗培养等,最终获得了生长正常的杂种F1植株。同时,通过对杂种幼胚愈伤组织、根尖细胞的细胞学观察,结果表明该杂种为真杂种,即2n=5x=35(预期染色体数)的杂种细胞占主体;另外,因组培过程中发生了染色体数目的变异,故也有少量2n=28-34染色体数的细胞。以上杂种的获得为将旱麦草优异基因向小麦的转移奠定了基础。 相似文献
65.
ABA和NAA联合使用能有效地诱导水稻原生质体再生的愈伤组织向胚性发展。通过液体浅层培养由原生质体得到的愈伤组织,在含ABA和NAA的N_6培养基上培养一段时间,可以诱导原来呈非胚性状态的愈伤组织形成胚性愈伤组织,并在含ZT的N_6分化陪养基上产生绿点。通过对这两种愈伤组织的生化分析,表明二者在游离氨基酸、DNA、RNA、核酸及蛋白质含量等方面,特别是SDS-PAGE谱带存在明显的差异,其细胞的形态与结构也有显著差别,其中经ABA NAA诱导后的愈伤组织其细胞形态与结构特征与来源于种胚的胚性愈伤组织基本类似,所分析的生化指标也大多数相近。结果表明,ABA和NAA联合使用得当,能促进形成胚性愈伤组织。 相似文献
66.
Enhanced production and accumulation of free and conjugated polyamines as well as increased activities of their biosynthetic enzymes in plants have been associated with heat stress. Perchloric acid-soluble free, as well as conjugated polyamines, and their metabolic enzymes were studied under 45°C heat stress in callus raised from heat-tolerant and -sensitive rice cultivars. The levels of free and conjugated polyamines, as well as arginine decarboxylase (EC 4.1.1.19) and polyamine oxidase (EC 1.4.34) activities were higher in tolerant than in sensitive callus under non-stressed conditions. Heat stress caused greater accumulation of free and conjugated polyamines in callus of the heat-tolerant cultivar N22 than in that of the heat-sensitive cultivar IR8. In particular, the uncommon polyamines norspermidine and norspermine were detected in cv. N22, which increased appreciably during stress, but they were not detected in callus of cv. IR8. Arginine decarboxylase and polyamine oxidase activities increased to a larger extent in N22 than in IR8 callus during stress, activities that were well correlated with the increased levels of common and uncommon polyamines. Increased levels of transglutaminase activity indicated the high titre of conjugated polyamines. 相似文献
67.
In vitro cultures of O. reclinata accumulate red anthocyanin pigments. Two callus lines were established from O. reclinata, one red and the other non-pigmented. The red callus accumulated cyanidin-3-glucoside as a major pigment. Light irradiation induced anthocyanin synthesis in white callus, resulting in a heterogenous red callus line being formed. The incubation of red and white callus cultures in the dark or at low-light resulted in the repression of red pigment accumulation. The application of 2,4-D (1.0 mg l-1) inhibited pigment production in the white callus and decreased anthocyanin accumulation in the red callus. The polypeptide composition of the red and white callus lines from O. reclinata were compared using two-dimensional electrophoresis. The red callus had a larger subset of neutral and acidic polypeptides. 相似文献
68.
69.
Midrib sections of Mussaenda 'Queen Sirikit', 'Do?a Luz', and 'Do?a Hilaria' were cultured on Murashige and Skoog medium (MS) supplemented with 87.7 mM
sucrose, 5 g agar l−1, 0, 5, 10 or 20 μM indole-3-acetic acid (IAA) and 0, 0.5, 1, 2.5, 5, 10, 25 or 50 μM 6-benzyladenine (BA). In addition, aseptic
5 mm shoot tips from 'Do?a Luz' cultures were excised and cultured on MS basal salts, 0.6 mM myo-inositol, 1.2 μM thiamine-HCl,
87.7 mM sucrose, 7 g agar l−1, 0, 2.5, 5, 10, 20, or 40 μM BA, 0 or 1 μM α-naphthaleneacetic acid (NAA) and 0 or 217 μM adenine sulfate at pH 5.8. Calluses
began to develop after two weeks at the cut ends of midribs when cultured on a medium containing IAA. Somatic embryos first
appeared at eight weeks but only on 'Queen Sirikit' callus. After 15 weeks, the average number of somatic embryos produced
per tube decreased as the IAA concentration increased from 0 to 20 μM. BA concentrations between 5.0 and 10.0 μM resulted
in the largest number of somatic embryos per tube. After six weeks, the total, axillary and adventitious number of 'Do?a Luz'
shoots increased as the BA concentration in the culture medium increased from 0 to 20 μM. Average shoot length and fresh weight
decreased from 0 to 40 μM BA. The addition of NAA to the culture medium reduced shoot number. Adenine sulfate in the presence
of BA reduced the total number of shoots. An ideal medium for proliferating the largest number of 'Do?a Luz' shoots would
be a MS medium supplemented with 10–20 μM BA.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
70.
Hamidah Musa Karim Abdul Ghani Abdul Debergh Pierre 《Plant Cell, Tissue and Organ Culture》1997,48(3):189-193
The effects of xylooligosaccharides isolated from the cell walls of Betula platyphylla var. japonica on cells and protoplasts
of Pinus radiata were examined. The addition of a semi-purified mixture of xylooligosaccharides at a concentration of 5μg.ml−1 promoted elongation of cultured cells, whereas the neutral fraction of this mixture had no effect; a similar effect was seen
in the presence of conditioned medium. The unfractionated mixture of xylooligosaccharides was also found to enhance the viability
of protoplasts prepared from cell cultures of Pinus radiata in a concentration dependent manner, highly similar to the effect
provided by addition of medium conditioned by pine cells. Such effects are considered to be due to the addition of components
that play a structural role in the cell wall of pines. It is inferred that the acidic components of the xylooligosaccharide
mixture derived from t Betula are responsible for this effect in the distant pine species. It is speculated that acidic xylooligosaccharides
operate either by replacing, or mimicking, the natural cell wall components required for growth and development of pine cultured
cells.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献