拮抗细菌B8对烟草黑胫病菌的抑制作用及其菌株鉴定

Inhibition of an Antagonistic Rhizobacteria B8 to Phytophthora parasitica var. nicotianae and Its Identification

从烟草根际土壤中分离到对烟草黑胫病菌及其它植物病原菌具有抑制作用的菌株B8,平板对峙培养抑菌带内菌丝畸形、原生质凝集或外渗。其发酵原液和发酵液的无菌滤液均能抑制烟草黑胫病菌和蜡状芽孢杆菌;离体叶片接种法测定其发酵液对烟草黑胫病的防效,结果表明预防作用达100%。室内盆栽试验表明B8菌株发酵液对烟草黑胫病的预防作用可达78.1%,优于治疗作用。该菌菌体杆状,芽孢侧生、椭圆形,经形态学、生理生化性状和16S rDNA序列测定,将其鉴定为侧孢短芽孢杆菌。

Bacterial strain B8 was isolated from the rhizosphere soil It showed significant inhibition against Phytophthora parasitica var. in petri-dishes. The mycelia of P. parasitica var. nicotianae was d of tobacco plants in Fujian province. nicotianae and other plant pathogens amaged in inhibition zone, expressing malformation, protoplasm agglomerated or exosmotic. Both the fermentation liquid and its filtration could inhibit P. parasitica var. nicotianae and Bacillus cereus effectively. Control effects were about 100% and 78.1% in vitro and in greenhouse tests, respectively, when tobacco seedlings were treated with B8 fermentation liquid, indicating its prevention to the disease. Strain B8 was identified as Brevibacillus lateroporus by its morphology, physio-biochemical tests and 16S rDNA sequence analysis.