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排序方式: 共有73条查询结果,搜索用时 171 毫秒
1.
大白菜游离小孢子培养胚胎发生中的加倍机制   总被引:6,自引:0,他引:6  
 利用Leica体视显微镜, DAPI荧光染色观察比较大白菜小孢子正常发育为成熟花粉粒与游离小孢子培养胚胎发生细胞核的分裂方式, 探讨大白菜游离小孢子培养胚胎发生及其自然加倍的机理。观察结果显示以B途径为主要发育途径的大白菜小孢子, 胚胎发生的启动机制是热激诱导下单倍体小孢子体积膨大, 染色体发生自然加倍, 从而激发小孢子进入孢子体发育途径; 大白菜小孢子胚再生植株具有较高的自然加倍率, 这与小孢子培养热激诱导激发小孢子单核自然加倍为二倍体密切相关。  相似文献   
2.
芥蓝游离小孢子培养及植株再生研究   总被引:1,自引:2,他引:1  
对12个基因型的芥蓝进行了游离小孢子培养及植株再生研究.结果表明:供体基因型对诱导胚胎发生至关重要;最佳热激温度为32℃,24h;单核靠边期到双核期的小孢子最适合进行胚胎诱导;NLN培养基中的最佳蔗糖浓度为130 g·L-1;添加活性炭可以提高成胚速度和质量;15~25 ℃的供体植株生长的环境温度决定着游离小孢子培养的成败,将子叶型胚胎转移到MS固体培养基上可直接发育成植株.  相似文献   
3.
Purple flowering stalk (Brassica campestris ssp. chinensis var.purpurea Hort.) was generally regarded as a recalcitrant species for microspore culture in Brassica crops. Conditions for reliable induction of microspore embryogenesis were studied in 12 genotypes of purple flowering stalk. A treatment of short heat shock to microspore by incubating at 32 °C for 18 h was suitable for the survival of microspores, sustained cell divisions, and further induced embryogenesis. Subsequently, the reduced concentration of macro salts (1/2 NLN) provided an optimal condition for the development of embryoids. Under the optimized conditions for microspore embryoid development, 10 genotypes responded to microspore culture with the frequencies ranging from 2.7 to 70.5 embryoids per dish. However, regenerated plants were obtained from 9 genotypes, and more than 75% these regenerated plants were double haploid. This report establishes an efficient protocol for microspore culture and offers great potential for DH breeding in purple flowering stalk.  相似文献   
4.
The present study compared the carbohydrate metabolism of pelagic eggs of three marine species, Serranus cabrilla (Serranidae), Mullus barbatus (Mullidae) and Sparus aurata (Sparidae). In particular, in Serranus cabrilla and Mullus barbatus the changes in carbohydrate metabolism from the vitellogenic follicle stage to the ovulated egg stage (final maturation of the egg) were investigated, and in Sparus aurata the changes from the unfertilized egg stage to the late-embryo stage just before hatching were observed. In mature, unfertilized eggs of these three species the qualitative and quantitative composition of carbohydrates, enzymes and metabolites were similar, indicating no differences in carbohydrate metabolism. Glycolysis, gluconeogenesis and the pentose phosphate pathway occurred in the follicles and eggs. From the vitellogenic follicle stage to the mature egg stage glycolytic activity was constant in S. cabrilla and M. barbatus, while the activity of the pentose phosphate pathway and of gluconeogenesis decreased. Quantitative carbohydrate composition changed as the levels of hexose, ketose, 6-deoxyhexose, uronic acid and fructose-6-phosphate increased from the vitellogenic follicle stage to the mature egg stage, while the levels of D-glycerate-2-phosphate and phosphoenolpyruvate decreased. In S. aurata, the investigated parameters of carbohydrate metabolism were similar between unfertilized eggs and eggs in the first cleavage stage. From the first cleavage stage to the late embryo stage the levels of hexose, 2-deoxyhexose, ketose, ribose, uronic acid and phosphoenolpyruvate increased, while the levels of D-glycerate-2-phosphate decreased.  相似文献   
5.
17个用于大白菜常规育种的基因型在NLN-13液体培养基中进行游离小孢子培养,结果有16个基因型经由小孢子胚胎发生途径获得小孢子胚。这些基因型包括从早熟晚熟的各种类型。各基因之间在小孢子胚胎发生频率方面存在很大差异,产量最高的两个基因型T11和CC11,平均每百花蕾分别达35928和34132个胚。供体植株生长环境对小孢子胚胎发生具有明显影响;在10/20℃(液/昼)的部分控温温室生长的供体植株,  相似文献   
6.
珍稀药用植物延龄草的体细胞胚诱导研究   总被引:1,自引:0,他引:1  
[目的]探索延龄草的有效繁殖途径。[方法]以延龄草的未成熟种子为外植体,在MS培养基上添加不同的激素配比,在黑暗和光照条件下进行组织培养。[结果]光照条件下,MS+2.0 mg/L6-BA+1.0 mg/L NAA启动延龄草未成熟种子的频率最高,达100.0%;黑暗条件下,MS+2.0 mg/L6-BA+2.0 mg/LIAA启动延龄草的频率最高,达100.0%。光照有利于延龄草未成熟种子启动程度的增加。MS+1.0mg/L6-BA+0.5 mg/LNAA适合诱导延龄草未成熟种子胚性愈伤组织分化和胚状体的发生。显微观察发现诱导出来的延龄草胚状体多处于球形胚和球心胚阶段。[结论]适合延龄草未成熟种子启动的培养基是MS+2.0mg/L6-BA+1.0mg/LIAA。  相似文献   
7.
选择我国棉花优良品种泗棉3号进行组织培养,获得了具有高频胚胎发生的愈伤组织、胚状体和小植株。在附加ZT的MS培养基上,泗棉3号的下胚轴、子叶、根均诱导获得了愈伤组织,但其形成率和形成量不同,其中下胚较易诱导获得愈伤组织,根和子叶较差。ZT对愈伤组织形成和生长影响较大,其在愈伤组织诱导中较适的使用浓度为3.0或5.0mg/L。  相似文献   
8.
生长素诱导大豆未成熟子叶胚胎发生效应的研究   总被引:5,自引:0,他引:5  
用 2 ,4_D与萘乙酸两种生长素的各 4种浓度诱导大豆未成熟子叶胚胎发生。结果表明 ,两种生长素均可诱导胚胎发生 ,并且胚胎发生率和平均胚数在两种生长素间无显著差异 ;品种在平均胚数上存在差异。高浓度的 2 ,4_D诱导胚胎发生效果好于低浓度 ,诱导率达 4 1 2 3%。同时 ,观察到诱导大豆未成熟子叶胚胎发生时 ,开始第一周高浓度的 2 ,4_D对胚胎发生有更重要的作用  相似文献   
9.
王萍  王罡  季静 《大豆科学》2005,24(4):314-316
以8个菜用大豆品种的未成熟子叶为外植体,在MS(附加高浓度2,4-D)培养基诱导愈伤组织形成、体细胞胚胎发生与再生植株.结果表明:八个菜用大豆品种的未成熟子叶均可诱导产生愈伤组织与体细胞胚胎发生,出愈率为14.71%~100%.体细胞胚胎发生率变化在0~36.76%之间,绿子叶菜用大豆没有形成体细胞胚.体细胞胚可正常萌发产生小植株,移栽成活结实.菜用大豆的出愈率和体细胞胚胎发生率与基因型有关.  相似文献   
10.
‘Success’ or ‘Red Splendor’ plants propagated by shoot tip culture or embryogenesis had higher pollen germination than those propagated by cutting. All clones of ‘Pepride’, ‘Peter Star’ and ‘Nobel Star’ propagated by cutting or by embryogenesis or shoot tip culture did not have viable pollen. ‘Peter Star’ mutants through mutagenesis could recover pollen viability. When both parents were propagated by tissue culture, fruit set increased compared to when one or both parents were propagated by cuttings. Furthermore, the number of the harvested seeds doubled per pollination set, when the tissue culture parents were used instead of cutting-propagation plants.  相似文献   
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