中国农业科学2012，Vol.45Issue(18)：3764-3772,9.DOI:10.3864/j.issn.0578-1752.2012.18.009
利迪链霉菌A01活性代谢产物对甘蓝枯萎病菌的抑制作用及其机理
The Antifungal Activity and Action Mechanism of Metabolite Produced by Streptomyces lydicus Strain A01 Against Fusarium oxysporum f.sp.conglutinans
摘要
Abstract
[Objective] The objective of this study is to understand the antifungai activity and action mechanism of natamycin produced by Streptomyces lydicus strain A01 against Fusarium oxysporum f. sp. Conglutinans, and to provide a scientific basis for product development and application of strain A01. [Method] Mycelial radial growth assay and microscope concave slide method were used to test suppression of mycelia growth and inhibition of spore germination. Electrical conductivity method and methylene blue stain were used to test permeability of pathogen plasma membrane and cell viability of this pathogen. SEM and TEM observations were used to observe morphology and ultrastructure of mycelia. [Result] The MICs of natamycin against the mycelia growth and the conidial germination of F. oxysporum f. sp. Conglutinans were less than or equal to 31.92 and 41.04 μg·tnL-1, respectively, and the IC5O and EC50 were 8.69 and 3.06 μg·mL-1, respectively. After being treated by natamycin at concentration above 30 μg·mL-1 for more than 90 min, the electrical conductivity of the mycelial suspension was significantly increased. The action intensity was correlated positively with natamycin concentration and the action time. The changes in morphology and cell ultrastructure of the treated mycelia were observed under SEM and TEM, such as abnormal growth or malformation, disintegration of organelles, cell vacuolization and so on. The mycelia treated with natamycin over 10 μg·mL-1 for 120 min could be stained with methylene blue. [Conclusion] The active metabolite of strain A01, natamycin, has obvious inhibitory activities against F. oxysporum f. sp. Conglutinans. The bioactivity was based on that natamycin could increase the permeability of plasma membrane, destroy the mycelial morphology and cell ultrastructure, thus resulted in the disappearance of cell viability of the pathogen mycelium.关键词
利迪链霉菌/纳他霉素/甘蓝枯萎病菌/抑菌活性/作用机制Key words
Streptomyces lydicus/ natamycin/ Fusarium oxysporum f. sp. Conglutinans/ inhibitory activity/ action mechanism引用本文复制引用
卢彩鸽,刘伟成,刘霆,董丹,张涛涛,刘德文..利迪链霉菌A01活性代谢产物对甘蓝枯萎病菌的抑制作用及其机理[J].中国农业科学,2012,45(18):3764-3772,9.基金项目
北京市自然科学基金(6101001)、北京市农林科学院项目(2010A006)、北京市农林科学院青年基金 （6101001）
