烟草赤星病拮抗菌Q96的筛选鉴定及其防病效果研究

为分离筛选对烟草赤星病有良好防效的拮抗菌，以烟草赤星病链格孢菌为靶菌，从蚯蚓粪中经初筛和复筛获得拮抗菌，通过形态、生理生化特征和16S rDNA分析鉴定拮抗菌种类，并对烟草赤星病的防治效果进行了研究。结果表明，筛选出一株拮抗菌Q96，初筛和复筛的抑菌率均超过60%，经鉴定为副地衣芽孢杆菌（Bacillus paralicheniformis），其活菌液（稀释10倍）对孢子萌发和菌丝生长的抑制率分别为73.33%和79.68%，粗发酵液离体防效可达60.04%。Q96菌株可作为抗烟草赤星病生防菌剂的菌种资源。

Screening,Identification and Fermentation Condition Optimization of Antagonistic Bacterium Q96 Against Alternaria Alternata

In order to isolate and screen antagonistic bacteria with good control effect against A. Alternata. In this study, antagonistic bacteria were screened from vermicompost with A. alternata as the target fungus through initial screening and rescreening, and then the antagonistic bacteria were identified by morphological, physiological and biochemical characteristics and 16S rDNA analysis. The biocontrol effect of antagonistic fermentation broth was studied, and the fermentation conditions were optimized by the optimum design method. The results showed that antagonistic bacteria Q96 was screened out, and the inhibitory rate of the Q96 strain against A. Alternata was more than 60% after initial screening and rescreening. It was identified as Bacillus paralicheniformis. The inhibitory rates of spores germination and mycelial growth of the Q96 strain were 73.33% and 79.68%. The control effect of crude fermentation liquid was 60.04% in vitro. The Q96 strain can be used as a strain resource for biocontrol of tobacco brown spot.