中文摘要：

采用平板对峙法,从分离自土壤的436株细菌菌株中筛选对草莓根腐病菌——尖孢镰刀菌（Fusarium oxysporum）具有拮抗作用的细菌,得到了3株稳定性好,具有较高拮抗活性的菌株w-25、w-79和w-181。拮抗菌w-25对尖孢镰刀菌的抑菌带达到11.0mm,w-79和w-181的抑菌带分别达到5.4和6.4mm。此外,3株拮抗菌对草莓灰霉病菌（Botrytis cinerea）、草莓红中柱致病菌（Fragria ananassa）和草莓胶孢炭疽病菌（Colletotrichum gloeosporioides）等具有很强的拮抗作用。经过对3株菌株形态观察、理化分析和分子鉴定,认为w-25可能为荧光假单孢菌（Pseudomonas fluorescens）,w-181和w-79可能为枯草芽孢杆菌（Bacillus subtilis）。研究表明3株拮抗菌对致病菌生长有较好的抑制作用,显微观察发现拮抗菌代谢产物会破坏致病菌菌丝形态,电镜观察发现致病菌细胞器溶解,细胞内液泡变大。

英文摘要：

In order to screen antagonistic bacteria against Fusarium root rot of strawberry,totally 436 bacterial strains were isolated from strawberry rhizosphere soils.Three strains（w-25,w-79,w-181）were found to have high antifungi activities to Fusarium root rot of strawberry using five-point confrontation method,with inhibition zone of 11.0,5.4 and 6.4 mm,respectively.In addition,the three antagonistic bacteria on strawberry botrytis（Botrytis cinerea）,strawberry red column pathogens（Fragria ananassa） and strawberry gum spore anthrax（Colletotrichum gloeosporioides）have high antagonistic effect.According to their physiological and biochemical characters as well as 16S rDNA sequences,w-25 was probablely identified as Pseudomonas fluorescens,and w-181 and w-79 were probablely identified as Bacillus subtilis.Antagonistic bacteria（w-25,w-79 and w-181）can inhibit the mycelium growth.Their metabolic products treatment can lead fungi mycelium abnormality,bioplasm condensed and cellularvacuole increased,which was observed using light microscope and transmission electron microscopy.