KMS XINJIANG INSTITUTE OF ECOLOGY AND GEOGRAPHY，CAS
| 几种病原真菌毒素作为生物农药的开发利用 | |
| Alternative Title | Development and Utilization of Mycotoxins Produced by Several Pathogenic Fungi as Biopesticides |
| 魏彩霞 | |
| Subtype | 硕士 |
| Thesis Advisor | 邵华 |
| 2019-06-30 | |
| Degree Grantor | 中国科学院大学 |
| Place of Conferral | 北京 |
| Degree Discipline | 理学硕士 |
| Keyword | 生物入侵 意大利苍耳 植物毒活性 真菌毒素 生物除草剂 Biological invasion Xanthium italicum Phytotoxic activity Mytotoxins Bioherbicide |
| Abstract | 意大利苍耳(Xanthium italicum Moretti)为一年生菊科苍耳属植物, 原产地为北美, 现主要分布在东、西半球的中纬度地区, 是我国重要的外来入侵植物之一。意大利苍耳于 1991 年 9 月在北京市昌平区首次发现, 目前已蔓延至深圳、广西、河北、新疆、辽宁、山东等地。 生态模型预测显示, 意大利苍耳有可能进一步传播到中国的大多数地区。由于防控困难, 2007 年度意大利苍耳被列入《中华人民共和国省进口植物检疫有害生物名录》。意大利苍耳适应性强, 在多种生境中都能生长。该植物通过与当地物种竞争生态位及光照、养分等资源, 极易在新的地域中成为优势物种, 建立单优群落。 目前对于意大利苍耳的研究报道主要集中在其生物学特性及危害性等方面, 对意大利苍耳的防控研究较少。 本研究拟在实验室长期从事外来入侵植物研究的基础上, 从入侵植物意大利苍耳病叶中分离具有强致病性的病原菌, 并以病原菌为主要筛选对象, 从其次生代谢产物中发掘可用于防控意大利苍耳的活性化合物, 进而开发为生物除草剂。 研究结果如下:1. 意大利苍耳病原真菌的分离、纯化与筛选本研究通过常规组织分离法分离意大利苍耳病叶中的病原菌, 并通过经典的形态学方法和分子生物学方法对菌种进行鉴定。在入侵植物意大利苍耳病叶中分别分离出 4 个具有强致病活性的病原菌, 它们分别为链格孢 PFXI1(Alternariatenuissima)、弯孢霉 PFXI3(Curvularia sp.)、链格孢 PFXI4(Alternaria alternate)、链格孢 PFXI11(Alternaria tenuissima)；本文对其中的病原菌 PFXI3 及 PFXI11 进行了深入研究；2. 病原真菌 PFXI11 菌丝悬浮液及粗毒素的植物毒活性制备病原真菌 PFXI11 的菌丝悬浮液和粗毒素, 并测试其除草活性。研究结果表明:将制备的菌丝悬浮液喷洒在杂草意大利苍耳叶面上, 接种后 48 h 后植株叶片出现明显病斑点； 3 d 后植株患病率达 100%, 整个植株叶片已经开始失水黄化； 10 d 后整个植株萎蔫死亡；将制备的真菌粗毒素配制为 5 mg/mL 的溶液并均匀喷洒在野外杂草意大利苍耳植株上, 喷雾处理 5 d 后, 意大利苍耳植株死亡。3.病原真菌 PFXI3 中病原毒素的分离纯化、植物毒活性；以活性跟踪方法对病原真菌 PFXI3 毒素进行分离纯化, 从中鉴定出 3 个具有强植物毒活性的化合物, 其中包括一个全新炔类真菌毒素, 将其命名为Curvularioxide, 以及两个已知化合物脱氢根素 Radicinin 和脱氢根生素Dehydroradicinin, 并对这 3 种化合物进行了植物毒活性测定和叶片针刺试验, 结果表明:(1) 在化合物的植物毒活性试验中, 3种化合物整体呈现出“低促高抑”的现象,在 1 µg/mL浓度下, 所有的化合物几乎呈现出不同程度的促进作用, 在 20 µg/mL-500 µg/mL 浓度下, 3 种化合物整体呈现出了剂量效应, 即随着化合物浓度的增高, 植物毒的作用呈现出增长趋势；(2) 在化合物的叶片侵染实验试验中, 化合物 Curvularioxide 和Dehydroradicinin 对意大利苍耳叶片的损害程度显著, 具有开发为除草剂的价值。 |
| Other Abstract | Xanthium italicum Moretti (family Asteraceae, Compositae), an annual invasiveweed, is native to America and has spread into many undisturbed natural areas. Itcurrently mainly distributes in the middle latitudes of the eastern and westernhemispheres. where it has negative influence through compete with native plants forspace, nutrients, and water, which causing significant ecological damage. X. italicumwas first discovered in September 1991 in Changping District, Beijing. It has spread toShenzhen, Guangxi, Hebei, Xinjiang, Liaoning and Shandong. Ecological modelingpredicted that X. italicum may spread further to most parts of China. In 2007, X. italicumwas listed on the quanrantine list of imported pests in the People's Republic of China.X. italicum has strong adaptability and can grow in various habitats; it can easilyestablish dominance and form monocultrue in the invaded regions by competing againstnative species for niche, sunlight and nutrition.Published studies on X. italicum mainly focus on its biological characteristics anddamage, however there is not many reports on its control. Our research objective isscreen pathogenic fungi and their secondary metabolites so that they can be utilized asenvironment friendly bioherbicides. The results are as follows:1. Isolation, purification and screening of pathogenic fungi from X. italicumPathogenic fungi in X. italicum leaves were isolated by conventional tissueisolation method, and identified by classical morphological and molecular biologicalmethods. Four pathogenic bacteria with strong pathogenic activity were isolated frominvasive plant X. italicum. They were Alternaria tenuissima PFXI1, Curvularia sp.PFXI3, Alternaria alternate PFXI4 and Alternaria tenuissima PFXI11. The pathogenicbacteria PFXI3 and PFXI11 were studied in depth.2. Phytotoxic activity of mycelial suspension and crude toxin of pathogenic fungusPFXI11Phytotoxic activity of mycelial suspension and crude toxin of pathogenic fungusPFXI11 was tested. The results showed that the mycelial suspension of pathogenic fungi was sprayed on the leaves of X. italicum, and the disease spots appeared 48 hoursafter inoculation; after 3 days, the disease rate reached 100%, and the leaves of thewhole plant began to wither and became yellowish. And 10 days later, the whole plantwithered and died. The crude toxin was prepared into 5 mg/mL solution and evenlysprayed on the wild weed X. italicum. After spraying 5 days on plants, the plants of X.italicum died.3. Isolation, purification and phytotoxicity of pathogenic toxins from pathogenicfungi PFXI3Three compounds with strong phytotoxic activity were identified from crude toxinof pathogenic fungus PFXI3, including a new alkyne mycotoxin named curvularioxide,and two known compounds, dehydrogenin and dehydroradicin. The phytotoxicity andleaf puncture tests of the compounds were carried out. The results showed that:(1) By testing the phytotoxicity of the 3 compounds, they exhibited promotiveactivity at low concentrations and inhibitory activity at high concentration. At theconcentration of 1 µg/mL, almost all the compounds showed different degrees ofpromotion. When the concentration reached 20 µg/mL to 500 µg/mL, three compoundsshowed strong suppressive activity in a dose dependent manner.(2) By testing the leaf infection of the 3 compounds, curvularioxide anddehydroradicinin caused more severe damage to the leaves of X. italicum, indicatingtheir potential to be utilized as bioherbicides. |
| Subject Area | 植物学 |
| Language | 中文 |
| Document Type | 学位论文 |
| Identifier | http://ir.xjlas.org/handle/365004/15379 |
| Collection | 中国科学院新疆生态与地理研究所 研究系统 |
| Affiliation | 中国科学院新疆生态与地理研究所 |
| First Author Affilication | 中国科学院新疆生态与地理研究所 |
| Recommended Citation GB/T 7714 | 魏彩霞. 几种病原真菌毒素作为生物农药的开发利用[D]. 北京. 中国科学院大学,2019. |
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