抗小麦白粉病的真菌寡糖激发子结构鉴定与诱导机制

Oligosaccharide elicitor is a kind of inducer with highly inducing plant resistance reaction, which has a important using prospect in plant disease biological control.Target pathogen of the test was Blumeria graminis f.sp.tritici: 1) Oligosaccharide elicitors from fungi strains were isolated with Using enzymatic extraction、acid hydrolysis and pyrolysis, and tested for their biological activities to trigger the defense reactions on soybean cotyledons.Detached-leaf-segment and greenhouse potted for testing the control effect of wheat powdery mildew with oligosaccharide elicitors, we obtained oligosaccharide elicitors with high activity and control effect.2) High purity oligosaccharide elicitors were obtained by column chromatography and HPLC, which structure were identified by mass spectrometry and nuclear magnetic resonance, and the ralation between their biological activities components with structure was analysed. 3) The study about oligosaccharide elicitors purity inducing the disease resistance mechanism to wheat were carried out, testing the dynamic state of PAL 、other defense-related enzymes 、lignin and so on such as resistance substances,We studied wheat gene differentially expressed using suppression subtraction hybridization, analying gene express profile, identifying disease resistance related gene, and showed the molecule mechanism of induced resistance with oligosaccharide elicitors. The research had important significance to expound the molecule mechanism of induced resistance on wheat powdery mildew with oligosaccharide elicitors from fungi strains.

寡糖激发子是一类高效引发植物抗性反应的诱抗剂，在植物病害生物防治中具有重要应用前景。本研究以小麦白粉菌为靶标菌：1）拟采用酶解法、酸解法、热解法分离来自真菌的寡糖激发子，大豆子叶法鉴定寡糖激发子的活性，离体叶段法及温室盆栽测定寡糖激发子对小麦白粉病的防效，从中获取高活性防效好的寡糖激发子；2）柱层析和HPLC纯化获得高纯度的寡糖激发子，利用质谱和核磁共振进行结构鉴定，分析寡糖的活性组分与结构的关系；3）研究寡糖激发子纯品诱导小麦的抗病机制，测定诱导后苯丙氨酸解氨酶等防御酶系及木质素等抗性物质的动态变化，应用抑制差减杂交技术研究寡糖激发子诱导后小麦基因差异表达情况，分析基因表达谱，鉴定抗病相关基因，从而揭示寡糖激发子的诱导抗性分子机制。该研究对揭示真菌源寡糖激发子对小麦白粉病的诱抗机制具有重要意义。