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以棉花等基因系超短纤维突变体(Ligon Li1)及其野生型(Ligon li1)为材料, 观察在田间生长和离体培养条件下纤维的超微结构, 分析纤维伸长的细胞学特点. 结果发现, 在田间条件下, 与正常纤维相比,突变体纤维在伸长趋向停止时, 细胞质稀薄, 小液泡增多, 线粒体、高尔基体和内质网减少, 细胞壁附近有较多游离或包含在质体中的淀粉粒, 推测功能性细胞器的缺乏和淀粉的糖转化受阻是突变体纤维细胞过早退化和停止伸长的主要原因. 在离体条件下, 突变体胚珠在含 GA3 的培养基中产生一种因生长快而形成的巨大愈伤组织, 它的表面覆盖一层白色、疏松、半透明、脆而易脱离胚珠的拟纤维细胞. 这种拟纤维细胞常被细胞壁分截, 形成不同于单细胞正常纤维的多细胞纤维, 且有黑色斑点分布, 如同田间棉花茎和叶上的色素腺体. 多细胞纤维质膜处有大量的微管, 初步具备次生壁沉积的条件, 推测赤霉素(GA3)可诱导在田间自然条件下沉默的与纤维细胞分裂相关基因的表达, 从而刺激表皮细胞己分化完成的原始纤维细胞再次迅速分裂.
The ultrastructure of the fiber under field and in vitro culture conditions was observed using the cotton Ligon Li1 and its wild type Ligon li1. The cytological characteristics of the fiber elongation were analyzed. The results showed that under the field conditions, compared with the normal fiber, the mutant fiber had thin cytoplasm, small vacuoles, reduced mitochondria, Golgi and endoplasmic reticulum, more free or contained in the vicinity of the cell wall Starch grains in the plastids, speculated that the lack of functional organelles and the blockade of starch glycoconjugation were the main causes of premature degeneration and elongation of the mutant fibroblasts.In vitro, the mutant ovules were cultured in medium containing GA3 Produces a huge growth due to rapid growth of callus, its surface covered with a layer of white, loose, translucent, brittle and easily detached from the ovule of fibroblasts. This fibroblasts often cut off the cell wall to form Different from the single-cell normal fiber multicellular fibers, and there are black spots distribution, like cotton stems and leaves in the field of pigmented glands .Multi-cell fibrous membrane at a large number of microtubules, preliminary Preparation of secondary wall deposition conditions, presumably gibberellin (of GA3) can be induced under natural field conditions related to expression of gene silencing of the fiber cell division, thereby stimulating fibroblast original has complete differentiation of epidermal cells divide rapidly again.