苹果病原真菌拮抗菌HMQAU140045的分离与鉴定

Isolation and Identification of an Antagonistic Bacteria Strain HMQAU140045 against Three Apple Pathogenic Fungi

为开发苹果病原真菌生防菌剂,采用稀释分离法、生长速率法、平板对峙法等从土壤中筛选出对苹果腐烂病(Cytospora mandshurica)、轮纹病(Botryosphaeria dothidea)、斑点落叶病(Alternaria mali)具有明显拮抗作用的菌株,并根据其形态、生理生化特征、16S rDNA序列分析等进行鉴定。结果表明,菌株HMQAU140045抑菌效果显著,对3种苹果病原真菌菌丝生长和孢子萌发均有显著抑制作用,经其无菌发酵滤液处理后,病原菌菌丝畸形,分支增多,局部膨大,分生孢子不萌发或萌发产生的芽管畸形肿大成球状泡。鉴定结果表明该菌株为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。

An antagonistic bacterium strain HMQAU140045 with strong inhibitory activity against three fungal pathogens from apple trees( e. g. Cytospora mandshurica,Botryosphaeria dothidea,and Alternaria mali) was isolated from soil by using dilution plate method,plate growth rate and flat confrontation culture method. The strain was identified as Bacillus amyloliquefaciens based on the 16 S rDNA sequence homology,the physiological and biochemical characteristics and morphological observation. The strain had significant inhibitory effect on mycelial growth and spore germination of the three apple pathogenic fungi. After treated by HMQAU140045 fermentation filtrate,the mycelia were malformed,spores did not germinate or generated germ tubes swollen to form spherical bubbles.