药用植物二色补血草内生真菌分离及其抑菌活性初步研究

Isolation of Endophytic Fungi from Limonium bicolor(Bge.) Kuntze and Their Microbial Inhibition Activities

对药用植物二色补血草内生真菌进行分离,以番茄灰霉病菌、黄瓜枯萎病菌、枸杞黑果病菌、黄瓜立枯病菌、小麦全蚀病菌、枯草芽孢杆菌、大肠杆菌、金黄色葡萄球菌和铜绿假单胞菌为靶标菌,采用对峙法和改进的菌块法进行抗菌活性初步筛选。结果表明:(1)从二色补血草根、茎、叶组织器官中分离出18株内生真菌,其中以叶部最多,根部和茎部次之;经形态学初步鉴定归于2目,2科,4属。(2)有10株内生真菌对2种或多种植物病原真菌有不同程度的抑制作用,占分离菌株总数的55.6%;8株内生真菌对1种或多种供试细菌具有不同程度的抑制作用,占分离菌株总数的44.4%;菌株LBEFL001和LBEFL006分别对5种供试真菌具有明显抑制作用,属于曲霉属和青霉属;菌株LBEFR006、LBEFS002分别对金黄色葡萄球菌和铜绿假单胞菌2种供试细菌具有明显抑制作用,属于梭孢霉属;菌株LBEFL004对枯草芽胞杆菌和金黄色葡萄球菌2种供试细菌具有明显抑制作用,属于曲霉属。研究发现,二色补血草具有较为丰富的内生真菌资源,对植物病原真菌具有明显的抑菌活性,且抑菌范围较宽;对病原细菌抑制作用具有一定的选择性,总体上对金黄色葡萄球菌抑制作用明显。

The endophytic fungi were isolated from root,stem and leaf ot the host by nssue inoculation cul- ture and five pathogenic fungi and four bacteria strains used as targeting microbes to test microbial inhibi- tion activity by agar plate antagonistic action and modified agar gel diffusion methods. The results indicated that-（1）Eighteen fungal endophytic strains were isolated from the host. Most of them came from leaf,then root and stem, and the isolated strains attribute to four genera,two families,and two orders based on mor- phological characteristics. （2）For the isolated strains,ten of them were found to have some microbial inhi- bition activities against two or more pathogenic fungi, making up 55.6 % of the total isolates,and eight iso- lated fungi strains showed inhibition activities against one or more bacteria, respectively, reaching up to 44.4% of the total isolates in number. The strain LBEFL001 and LBEFL006 had evident antifungal activi- ties against 5 pathogenic fungal strains. They ascribed to Aspergillus sp. and Penicilium sp. individually. The strain LBEFR006 and LBEFS002 showed evident antibacterial activities to Staphylococcus aureus andPseudomonas aeruginosa, respectively. They both ascribed to Fusidium sp..The strain LBEFL004 ex- pressed evident antibacterial activities to Bacillus subtilis and S. aureus,belonging to Aspergillus sp.. It was found that the medicinal plant Limoniurn bicolor had relatively abundant fungal endophytic resource, and the isolatded endophytic fungi had evident inhibition activities against plant pathogens and showed rel- atively broad spectrum, and meanwhile the isolates as a whole had a certain of selectivity for bacterial inhi- bition,and inclined to be more antagonistic to S. aureus in general.