【作者】 王硕；

【导师】 慕小倩；

【作者基本信息】 西北农林科技大学 ， 植物学， 2006， 硕士

【摘要】 菊科(Compositae)植物是被子植物中较进化的、最大的一个科,其所含成分几乎包括了所有天然化合物类型。因此菊科植物是进行化感作用研究的理想材料。本课题组在研究10种北方常见的菊科野生杂草对小麦的化感作用时发现,黄花蒿(Artemisia annua L.)对小麦幼苗生长有显著的抑制作用。为了深入掌握黄花蒿的化感作用,本试验进一步对黄花蒿的化感效应及其机理进行了研究,旨在为其野生植物资源的合理利用以及新型天然无公害除草剂的开发提供理论依据。试验研究结果如下:1.应用室内培养皿法研究了黄花蒿水浸提液对小麦,白菜,油菜和黑麦草种子萌发的化感作用,结果表明,黄花蒿水浸提液延迟了受体种子的萌发;低质量浓度的黄花蒿水浸提液促进小麦和白菜种子的萌发,而高质量浓度的浸提液抑制了它们的萌发;试验范围内的质量浓度浸提液对油菜和黑麦草种子均表现为抑制作用。2.化感效应的研究结果表明,不同质量浓度的黄花蒿水浸提液对小麦、白菜、油菜和黑麦草的生长主要表现为抑制作用,质量浓度越高抑制作用越强。低质量浓度水浸提液对油菜和黑麦草处理后期苗的生长有微弱的促进作用。受体材料不同部位对黄花蒿水浸提液的敏感程度不同,根比苗敏感;同一受体材料不同的生长期对黄花蒿水浸提液的敏感程度也不同,苗期比发芽期敏感。3.黄花蒿化感作用形态学机制研究表明,黄花蒿水浸提液抑制了小麦根尖细胞的分裂和伸长,高质量浓度浸提液甚至造成了小麦根的结构发生改变。小麦根毛的生长和新根的发生也受到了抑制。这些导致了小麦幼苗的生长发育受到限制。4.对受试小麦根和苗的一些生理生化指标的测试结果表明,随着黄花蒿浸提液质量浓度的增加,小麦体内超氧化物歧化酶(SOD)、过氧化物酶(POD)和过氧化氢酶(CAT)活性均呈先升高后降低的趋势,根比苗的下降趋势显著。黄花蒿浸提液使小麦体内MDA含量升高,根系活力、叶绿素含量、核酸含量、可溶性糖和可溶性蛋白含量,以及淀粉酶活性下降。更多还原

【Abstract】 Compositae is the biggest and the most evolutional family of angiosperme. It contents most natural components and offers ideal donor plants for the studies on allelopathy. We have studied allelopathy of 10 species of Compositae plants worked on wheat, and found Artemisia annua L. strongly retarded wheat seedling growth. For further studies, we discussed allelopathy actions and its mechanisms of Artemisia annua L. The main results were as follows.1. Indoor Petri dish bioassay was adopted for studying the allelopathy of Artemisia annua L. worked on seed germination of wheat, cabbage, rape and ryegrass. The results showed that aqueous extracts of Artemisia annua L. could delay seed germination, reduce germination rate of rape and ryegrass. The aqueous extracts promoted seed germination rate of wheat and cabbage at low concentration but inhibited it at high.2. Study on allelopathy of Artemisia annua L. showed that its aqueous extracts restrained the growth of the test plants, and this inhibition became stronger when the concentration of the extract solution was higher. However, during the latter period of treatment, action of lower concentration on rape and ryegrass seedling turned to promotion. The root was more sensitive to aqueous extracts of Artemisia annua L. than seedling, and seedling stage was more sensitive than germination stage.3. Micro-observation on wheat roots showed that aqueous extracts of Artemisia annua L. restrained mitosis and cell enlongation. And the structure of root altered at high concentration. The outgrowth of root hair and new roots were inhibited.4. We mensurated some physiological and biochemical indexes of treated wheats. The results showed that with the concentration of the extraction solution rose, the activity of SOD, POD and CAT in vivo first increased and then decreased. The extract solution of Artemisia annua L. increased the content of MDA, but decreased the content of chlorophyll, nucleic acid, soluble protein and soluble sugar. It also reduced the activity of root and amylase.更多还原