Analysis of Biosynthesis and Physiological Activity of Lepidimoide-like Substance in Arabidopsis thaliana

以拟南芥为原料，研究了新型植物生长调节剂幻二醇酯的合成及其生理活性。利用高效液相色谱和薄层色谱对拟南芥（A.thaliana）生长植物的大部分器官（种子、莲座叶、茎、根、花序和未成熟果实）以及荠菜（Capsella Bursa-pastris）种子中均含有拟南芥（lepidimooid -样物质，LM.2）。结果表明，LM对拟南芥具有促进下胚轴伸长、子叶生长和子叶叶柄伸长的双重活性，但对根伸长有抑制作用。LM降低了莲座叶的生长、株高、植株鲜重、荚果数和种子产量。然而，在不减少莲座叶数量的情况下，LM加速了开花，说明LM在较短的时间内加速了叶片的发育。LM的这种作用加快了植物的生命周期。3 .我们从“仙台拟南芥种子储备中心”的大量生态型中寻找拟南芥敏感株系，筛选出Aa-0、Bur-0 2个株系，它们的下胚轴伸长和子叶生长都得到了明显的促进。十字花科植物种皮细胞具有中心凸起的差动结构，LM似乎就是从这里分泌出来的。因此，我们研究了新亲缘种芸苔属中心高地的形态。我们发现所有观察到的植物（10种）都有分泌粘液的中心海拔。然而，缺乏中心抬高的突变体种子分泌的LM也只有野生型的一半左右。我们将LM用于多种草本植物的幼苗，并根据植物种类和生长条件识别出不同的相反效果。

We studied on the synthesis and the physiological activities of the novel plant growth regulating substance, lepidimoide, using Arabidopsis thaliana.1. We analyzed lepidimoide-like substance (LM) by means of HPLC and TLC, and clarified that almost organs (seeds, rosette leaves, stems, roots, inflorescences and immature fruits) of growing plants of A.thaliana, and the seeds of Capsella Bursa-pastris included LM.2. We made clear that LM showed the two-faced activity in A.thaliana, i. e. promotion of hypocotyl elongation, cotyledon growth and cotyledon-petiole elongation, but inhibition of root elongation. LM reduced the growth of rosette leaves, plant heights, fresh weights of plants, pod number, yield of seeds. However, LM hastened flowering without decreasing number of rosette leaves suggesting LM accelerates the development of leaves within a shorter period. This effect of LM hastens the life cycle of plants.3. We made a search for sensitive lines of A.thallana from a large number of ecotypes in "The Sendai Arabidopsis Seed Stock Center", and selected 2 lines (Aa-0, Bur-0), hypocotyl elongation and cotyledon growth of which were markedlypromoted.4. The cells of seed coat of Brassicaceae have a differential structure, central elevation, from which LM seemed to be secreted. Therefore, we investigated the morphosis of the central elevations of newly related Brassica species. We recognized that all the plants (10 species) observed have the central elevation which secreted mucilage. However, the seeds of a mutant lacking the central elevation also secreted LM at about half amount of that in wild types.5. We treated LM to the seedlings of various herbaceous plants, and recognized various opposite effects according to plant species and growth conditions.