苗龄、基因型和外植体类型对黄瓜离体器官发生的影响

研究了苗龄、基因型和外植体类型对黄瓜离体器官发生的影响。结果表明 ,在水琼脂培养基上萌发的 4个黄瓜材料的种子 ,在萌芽后 1～ 4天时接种的子叶外植体出芽率及每外植体出芽数均较高 ,5天时明显降低 ,以 3～ 4天时最为合适。试验的1 2个不同基因型黄瓜材料愈伤诱导率均较高 ,且均能出芽。出芽率可大致分为高 (≥70 % )、中 (40 %～ 70 % )、低 (≤ 40 % ) 3类 ,以 T5 5 ,M9,P1 7出芽率最高 ,分别为76 % ,71 %和 73% ;以 K5 5 ,S8,S9×Q2 2出芽率最低 ,分别为 2 5 % ,39% ,40 %。各材料中 T5 5 ,P1 7,P1 7×Q2 2每外植体出芽数最多 ,分别为 3.40 ,3.43,3.82个。长春密刺和 K6 6子叶、下胚轴、胚根和真叶等外植体的愈伤诱导率均较高 ,但只有子叶出芽率和每外植体出芽数较高 ,下胚轴明显降低 。

植物离体器官发生控制机理研究进展

植物离体器官发生不仅是获得大量无性繁殖植物和进行基因转化的重要途径,而且亦是研究植物发育问题的主要实验系统之一。迄今为止,包括营养器官和生殖器官在内的几乎所有的器官都可以在离体条件下得到再生,为深入研究植物离体器官发生的分子机理奠定了基础。本文着重介绍了营养器官发生过程基因表达的调节及重要功能基因的作用,并对器官特征决定基因在生殖器官发生过程中的作用进行了分析,提出了揭示离体器官发生分子机理的主要途径。

茉莉离体器官发生及建立植株再生系统的研究

研究了离体条件下茉莉(Jasminum sambac)带腋芽茎段的器官发生和植株再生技术.离体培养以 MS 为基本培养基,结果表明:TDZ 诱导丛生芽的效果明显好于 ZT、6-BA 和 KT.其中以4.0mg·L^(-1)TDZ 和0.04mgL^(-1)NAA 的组合诱导效率最高,诱导频率达91.3%.诱导生根培养基以附加4.0mg.L^(-1)IBA 为最佳,生根率达100%.

Control of In Vitro Regeneration of Individual Reproductive and Vegetative Organs in Dracaena fragrans cv. massangeana Hort. Regularities of the Direct Regenerationof Individual Organs In Vitro

Various individual organs (tepal, flower bud, inflorescence branch, inflorescence, adult vegetative bud and juvenile vegetative bud) were directly regenerated respectively by callus in Dracaena fragrans cv. massangeana Hort. During the regeneration of these individual organs some regularity phenomena were observed. Firstly, the kind range of the individual organs, which are directly regenerated in vitro, is in close relationship to the differentiated stages of the organs used for explant excision during plant ontogeny. The explants excised from the epigeous organ that is differentiated at some stage (stage A) during plant ontogeny must be able to separately regenerate all of those individual epigeous organs: ones differentiated slightly later than the stage A, ones differentiated at the stage A and all ones differentiated earlier than the stage A. Secondly, within this range which kind of organ is regenerated depends on the exogenous auxin concentrations in medium. With the gradual increase of 2,4-D concentration from 0.005 mg/L to 0.5 mg/L, the kinds of regenerated organs will change by the order as follows: vegetative bud, inflorescence, inflorescence branch, flower bud, tepal. These regularities will be able to be used for inducing the direct regeneration of a given epigeous organ in angiosperms.

拟南芥不定芽发生早期的数字基因表达谱分析

目前,有关不定芽发生的研究主要集中在单基因的调控方面,缺乏转录组方面的系统研究。利用RNA-seq高通量测序技术在全基因组范围内检测了不定芽发生早期的基因表达谱,共检测到2 457个差异表达基因。这些基因参与了激素代谢和信号转导、愈伤组织和侧根的形成、茎顶端分生组织的发育和光合作用等过程。进一步的途径富集分析表明,不定芽发生早期苯丙氨酸代谢和苯丙胺素合成等途径相关的基因显著富集。并且苯丙氨酸可以显著抑制不定芽的发生,暗示了苯丙氨酸代谢和苯丙胺素的合成可能在不定芽发生过程起着重要的作用。