人参灰霉病菌拮抗细菌菌株筛选及鉴定

Screening and Identification of Antagonistic Bacterial Strains Against Botrytis cinerea on Ginseng

从林下参叶片中分离内生细菌,以人参灰霉病菌为指示菌,筛选拮抗菌株,基于形态学特征和16S rRNA基因序列分析,对拮抗菌株进行鉴定。结果表明,从林下参叶片中共分离得到56株内生细菌,其中菌株FS-1对人参灰霉病菌具有很好的抑制作用。采用生长速率法测定菌株FS-1的发酵液对8种植物病原真菌均有抑制作用。该菌株具有很好的固氮作用,且能够分泌吲哚-3-乙酸(IAA)和产生胞外蛋白酶,IAA产量为4.25 mg/L。通过形态特征观察、生理生化测定和16S rRNA序列分析结果,将菌株FS-1鉴定为蜡样芽孢杆菌(Bacillus cereus)。本研究表明菌株FS-1具有一定的生防潜力,可用于人参灰霉病的生物防治。

The endophytic bacteria strains were isolated from healthy mountain-cultivated ginseng leaves, and Botrytis cinerea was used asindicator fungus. Antagonistic strain was identified based on morphological characteristic and 16S rRNA sequence analysis. The results showed that 56 endophytic bacteria were isolated from healthy mountain-cultivated ginseng leaves, and strain FS-1 has good inhibitory effect to Botrytis cinerea. The antifungal effects of fermentation broth of strain FS-1 on eight plant pathogenic fungi were obvious. The strain FS-1 had the very good nitrogen fixation, it can secrete IAA, with an IAA yield of 4.25 mg/L, and produce extracellular protease. The strain FS-1 was identified as Bacillus cereus according to the morphological, physiological and biochemical characteristics, and 16S rRNA sequence analysis. This study suggests that strain FS-1 has certain potential biocontrol, and could be useful to effectively control Botrytis cinerea causing ginseng gray mold.