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排序方式: 共有169条查询结果,搜索用时 15 毫秒
1.
An efficient in vitro regeneration system by direct organogenesis from mature nodal and internodal stem segments of Newhall navel orange (Citrus sinensis L. Osbeck) was developed. Illuminating conditions together with plant growth regulators affected the adventitious bud regeneration frequency and efficiency. The initial 15 d darkness inoculation is beneficial for the adventitious bud regeneration. The highest regeneration frequency (85.2%) and bud formation efficiency (3.7 per responsive internodal stem segment) were obtained in the media supplemented with 1.0 mg L-1 BAP and 0.5 mg L-1 NAA. ABA at 0.2 mg L-1 positively affected the bud formation efficiency, which amounted to 8.5 buds per internodal segment in the presence of BAP at 1.0 mg L-1. The adventitious shoots successfully rooted and were transferred to the soil. 相似文献
2.
红花山玉兰组织培养外植体的选择及其消毒方法 总被引:2,自引:0,他引:2
为筛选出红花山玉兰组织培养适宜的外植体类型及其消毒方法,为红花山玉兰的无性繁殖提供技术支持,对灭菌时间、外植体类型和取材时间等进行研究。结果表明:茎段和顶芽的存活率分别为40.0%和33.33%,较叶片和叶柄的存活率高,且茎段和顶芽的存活率较叶片的存在显著差异,二者的死亡率均与叶柄和叶片的存在显著差异;茎段和顶芽为适宜的外植体。茎段在6月取材优于12月,且采用0.1%的升汞消毒10 min,其存活率为40.0%;顶芽在6月和12月取材均可,消毒后去除托叶能够有效地降低顶芽的污染率,提高其存活率。最佳消毒组合:先用75%的酒精表面喷洒预处理,再用0.1%的升汞消毒10 min,之后去除顶芽的托叶。该方法污染率和死亡率低,存活率最高,依次分别为6.67%、7.78%和85.55%,且芽启动率高。 相似文献
3.
苹果砧木M26离体叶片愈伤组织发生及分类研究 总被引:1,自引:0,他引:1
对苹果砧木M26 离体叶片愈伤组织的发生研究表明,取继代后30 ~35 d 的试管苗顶部1~4 叶位的叶片,沿与主脉垂直方向横切后,以叶背面朝上方式置于愈伤组织诱导培养基上,经观察在叶片近柄端切口处愈伤组织发生较早,产生量较多。最适的愈伤组织诱导培养基为:MS+2 ,4 - D0 .2 ~2 .0 mg·l- 1 +IAA0 .2 ~2.0 mg·l- 1 + BA0 .5 ~1.0 mg·l- 1 + 蔗糖3 % + 琼脂0.6% 。将诱导产生的愈伤组织按外部形态、细胞特点及生理生化指标等分为三类,其中表面干燥致密、细胞内含物丰富、淀粉、蛋白质及干物质含量均较高的Ⅲ类愈伤组织的芽再生频率最高,可达83 .33 % ,是能利用的愈伤组织类型。 相似文献
4.
黄花矶松组织培养技术 总被引:2,自引:0,他引:2
以黄花矶松的种子为材料,经过消毒后接种在不同激素水平的MS培养基上诱导小苗。结果表明:(1)MS 6BA0.3 NAA0.05培养基诱导率最高;(2)在不同配方的增殖培养基中MS 6-BA0.3 NAA0.6培养基的分化系数最高,苗长势最强;(3)在不同浓度的生根剂中MS/2 IBA0.6 NAA0.2培养基生根率最高,生根时间最短,且生根较一致,根系较发达,苗叶色正常,褐化程度较弱。 相似文献
5.
Tissue culture micropropagation of Douglas-fir 总被引:1,自引:0,他引:1
A procedure was developed for plantlet production from embryos of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco]. The Medium for Conifer Morphogenesis, used at full strength, and supplemented with 10 M benzyladenine for 17 days produced an average of 6.8 shoots on more than 90% of the embryos. The percentage of shoot-forming embryos as well as the average number of shoots per embryo varied significantly among eight seedlots. For secondary multiplication, 89% of the adventitious shoots produced axillary buds on MCM with 5 M benzyladenine. However, 0.5 M BA was more suitable for the elongation of axillaries. Rooting ranged from 0–87% depending upon the treatment. The highest percentage was obtained with a 7-week incubation in peat:perlite containing 1/5-strength medium, 1% sucrose and 2.7 M naphthaleneacetic acid, followed by 5 weeks on peat:perlite with 1/5-strength major and minor salts, full iron and organics, 1% sucrose and 0.1% charcoal. 相似文献
6.
A single-step method for the induction and development of somatic embryoids from hypocotyls explains of Brassica juncea is reported. On modified MS medium containing 2 % sucrose, 0.25 mgl 1 2,4-D, 0.5 mgl 1 each of NAA and BaP-R, each explant calluses at both of and at its best, 31% of explants produce embryoids. In the variety RLM-198, the number of embryoids ranges from 8–21 per culture. Each embryoid, upon proliferation, developed up to the 25 shoots. The method is rapid; the time La ken from inoculation to the development of intact plantlets is 8–10 weeks. Regenerated plants have flowered normally and have set seed. The system can profitably be used for in vitro mutant selection and early bulking in mustard. 相似文献
7.
Summary During experiments, which are being carried out to study the factors which control the process of adventitious bud formation in vivo on detached leaves of Chrysanthemum morifolium
Ram, adventitious shoots were produced from leaves, irradiated with 500 rad of X-rays. The most important but disadvantageous result was that the majority of the adventitious shoots proved to be of a chimeral nature and obviously developed from more than one cell.An in vitro adventitious bud technique was developed using different types of explants. Pedicel segments regenerated the highest number of adventitious shoots and, moreover, they developed faster as compared to explants of young flower heads or leaves. The mutants produced by irradiating the various explants were almost exclusively of a solid (non-chimeral) nature. In addition, histological observations suggest that single epidermal cells are involved in the initiation of the adventitious shoot apices.The optimum dose for mutant production is approximately 800 rad X-rays. Rather often, more than one phenotypically identical mutant was found, which was always derived from the same explant. They could for instance originate from a multi-apical meristem formed by a single mutated cell. 相似文献
8.
[目的]筛选出适合木薯组织培养的灭菌体系,为加快木薯组织快繁提供科学依据。[方法]以木薯品种GR891的腋芽为外植体,研究经甲基托布津杀菌剂处理和无处理外植体分别采用不同组合、不同处理时间对其表面灭菌的效果,同时研究6-BA和6-BA与NAA组合对丛芽诱导培养效果的影响。[结果]经甲基托布津杀菌剂处理后用体积分数75%乙醇消毒10 s+质量分数0.1%升汞处理8 min效果最好,外植体存活率为61.3%;以MS+6-BA 1.5 mg/L+糖30 g/L+琼脂6.5 g/L培养基诱导培养芽效果最好,有的丛芽能达到7~9株,丛芽生长速度快,健壮。[结论]建立了木薯GR891组织培养外植体灭菌与增殖培养体系。 相似文献
9.
水曲柳体胚发生过程中不同状态类型外植体的生理生化状态 总被引:2,自引:1,他引:1
以水曲柳Fraxinus mandshurica幼嫩合子胚子叶为外植体诱导水曲柳体胚发生,对该过程中外植体的不同状态类型分别取样,检测这些不同状态类型外植体的多糖含量、可溶性蛋白质含量及超氧化物歧化酶(SOD)、过氧化物酶(POD)、过氧化氢酶(CAT)、多酚氧化酶(PPO)活性等生理生化指标,分析不同状态类型外植体生理生化与体胚发生、愈伤组织发生、外植体褐化、外植体生长等方面的关系,以便为分析水曲柳体胚发生机理和改善其体胚发生技术提供依据.研究结果表明,不同状态类型外植体的生理生化状态与体胚发生、愈伤组织发生、外植体褐化和生长发育存在非常有趣的相关关系,值得进一步深入解析. 相似文献
10.
紫花苜蓿品种'德宝'不同外植体愈伤组织诱导研究 总被引:2,自引:2,他引:0
以紫花苜蓿'德宝'的下胚轴、叶片、子叶和叶柄为外植体,研究了不同浓度(1.5、2.0、2.5 mg/L)2,4-D对各外植体愈伤组织诱导的影响.结果表明:4种不同外植体的愈伤组织发生能力存在显著差异,下胚轴的愈伤组织诱导率最高,达98.5%,显著高于叶片(P<0.05),其他各外植体之间差异不显著.不同浓度2,4-D下各外植体愈伤组织发生也存在显著差异,浓度1.5 mg/L和2.0 mg/L的2,4-D MS培养基对愈伤组织的诱导效果优于浓度2.5 mg/L的2,4-D MS培养基(P<0.05),且有利于愈伤组织的胚性化.另外,2,4-D浓度在1.5~2.5 mg/L范围内,低浓度利于叶片和子叶愈伤组织发生,二者在1.5mg/L浓度下的愈伤率可达100%,显著高于2.5 mg/L浓度处理,而叶柄和下胚轴的愈伤率在各浓度下差异不显著. 相似文献