马铃薯糖苷生物碱对五种经济林病原真菌的抑菌活性及其机理研究

发布时间：2018-03-27 14:34

  本文选题：马铃薯糖苷生物碱　切入点：经济林病原真菌　出处：《甘肃农业大学》2017年硕士论文

【摘要】：随着经济林在林业经济可持续发展中的作用和地位的不断提高,其病虫害问题成为资源保护的焦点。当前,包括经济林在内的植物病虫害防治过于依赖化学药剂,造成林木及周围环境农残超标,严重影响经济林的生态效能、果实品质、林中天敌及人类健康。因此,研制开发高效、低毒、环保和低成本的新型无公害农药便成为了亟待解决的问题。马铃薯糖苷生物碱作为一种新型天然提取物质,在抑制植物病原真菌方面具有一定潜力,但其抑菌机理还未见系统研究。因此,本文通过马铃薯糖苷生物碱对五种主要经济林病原真菌的抑菌活性测定,寻找供试敏感菌株,研究马铃薯糖苷生物碱对其菌体结构、细胞形态以及物质代谢等的影响,初步探明其抑制机理。主要研究结果如下:1.离体条件下,马铃薯糖苷生物碱对五种经济林主要病原真菌:腐皮镰刀菌(Fusarium solani)、核桃盘二孢菌(Marssonina juglands)、煤炱菌(Capnodiume leaophilum)、链格孢菌(Alternaria alternata)、胶孢炭疽菌(Colletotrichum gloeosporioides)均表现一定的抑菌活性,且其抑制效果随浓度增加而增强。其中,对腐皮镰刀菌的抑菌活性最强,其EC50值为0.3036 g·m L-1。2.通过马铃薯糖苷生物碱的稳定性研究发现:在25℃、全光照、pH偏碱性条件下,马铃薯糖苷生物碱对供试敏感菌株——腐皮镰刀菌的抑菌效果最好;而马铃薯糖苷生物碱具有良好的热稳定性。3.透射电镜观察显示,经马铃薯糖苷生物碱处理后,菌丝细胞壁呈泡状起伏,外层结构不完整,细胞膜不连续,线粒体等细胞器结构紊乱,细胞外有可见内含物外渗,表现出对菌体形态结构的显著影响作用。4.物质代谢研究表明,马铃薯糖苷生物碱破坏菌体细胞膜的选择透性,引起内部脂质、蛋白质和糖类等物质的大量外渗,阻碍了菌体对还原性糖的水解,影响菌体营养物质的吸收利用,菌体的分解代谢受到了抑制。
[Abstract]:With the continuous improvement of the role and status of economic forest in the sustainable development of forestry economy, the problem of plant diseases and insect pests becomes the focus of resource protection. At present, the control of plant diseases and insect pests, including economic forests, is too dependent on chemical chemicals. It causes the forest and its surrounding environment to exceed the standard, seriously affects the ecological efficiency, the fruit quality, the natural enemy and the human health of the economic forest. Therefore, the research and development of high efficiency and low toxicity, Environmental protection and low cost of new pollution-free pesticides have become a problem to be solved. As a new natural extract, potato glycoside alkaloids have a certain potential in inhibiting plant pathogenic fungi. However, the bacteriostatic mechanism of potato glycoside alkaloids has not been systematically studied. Therefore, the antimicrobial activity of potato glycoside alkaloids against five main economic forest pathogenic fungi was determined to find the sensitive strains and to study the structure of potato glycoside alkaloids on their mycelia. The effects of cell morphology and substance metabolism on the inhibition mechanism were preliminarily investigated. The main results are as follows: 1. In vitro, Potato glycoside alkaloids showed certain antimicrobial activity against five main pathogenic fungi in economic forest: Fusarium solanii, Marssonina juglandsof walnut, Capnodiume leaophilumophilus, Alternaria alternata, Colletotrichum gloeosporioides. The inhibitory effect was enhanced with the increase of concentration, among which, the inhibitory activity against Fusarium vulgaris was the strongest, its EC50 value was 0.3036 g mL ~ (-1). The stability of potato glycoside alkaloids was studied at 25 鈩，

本文编号：1671929