虫草及相关真菌发酵产物对烟草黑胫病的抑制效果

摘要

In order to explore the fungal secondary metabolites antifungal activity on P.nicotianae,in this study,fermentation broth of 75 strains of C.sinensis and related fungi from all over the world were used in antifungal activity experiment on P.nicotianae by mycelium growth velocity.Bionectria ochroleuca,Paecilomyces tenuipes,Bionectria ochroleuca and Fusarium oxysporum and cordycepin were selected for in vitro cytotoxic test.The results indicated that 30 samples (40.00％) had a strong inhibitory effect on P.nicotianae,and improved the effect with dosage increase.The cordycepin extracted from liquid fermentation broth of C.militaris had significant antifungal activity on P.nicotianae,and also improved the effect with dosage increase with the EC50value of 77.98 g/mL.%为了探索真菌次生代谢产物对烟草黑胫病的抑茵活性,采用生长速率法,对来自全球的75株虫草及相关真菌菌株发酵液进行活性筛选,并对活性较强的白色生赤壳[Bionectria ochroleuca (Schwein.)Schroers&Samuels](四川)、细脚拟青霉[Paecilomyces tenuipes (Peck) Samson]、白色生赤壳[Bionectria ochroleuca (Schwein.)Schroers&Samuels](韩国)和尖孢镰刀菌(Fusarium oxysporum Schltd)4种发酵虫草液及虫草菌素进行不同浓度的室内毒力测定.结果表明:对烟草黑胫病菌菌丝生长具有抑制作用的有30株发酵液,占总筛选菌株的40.00％；4种真菌发酵液对烟草黑胫病菌具有较强的抑制作用,且随使用剂量的增大而增强；从蛹虫草液体发酵液中提取的虫草素对烟草黑胫病菌也具有明显的抑制作用,且随使用剂量的增大而增强,其有效抑制中浓度EC50=77.98 μg/mL.