番茄细菌性斑点病生防菌的鉴定、防病及定殖力

Identification of biocontrol bacterial strain and its antagonistic activity to tomato bacterial speck and colonizing ability in tomato

从4种茄科植株中分离得到28株对番茄细菌性斑点病菌有拮抗作用的内生细菌.其中,从番茄中分离的Fq7菌株抑菌效果最好,抑菌圈半径为8 mm;室内盆栽条件下,处理7 d后对番茄细菌性斑点病的防治效果达62.71%.通过形态特征观察、生理生化特性测定和16S rDNA序列分析,Fq7菌株被鉴定为解淀粉芽孢杆菌.Fq7菌株在番茄体内的定殖结果表明:采用涂抹叶片和浇灌土壤的方法接种于番茄,均可在番茄根、茎、叶中分离回收到细菌菌株,表明Fq7菌株可以在植株体内繁殖和传导,具有沿维管束转运的能力.

Twenty-eight endophytic bacterial strains were isolated from four species of solanaceae plants, which showed antagonistic effect against Pseudomonas syringae pv. tomato. Among them strain Fq7 showed the best bacteriostatic effect, the diameter of its in- hibition zone was 8 ram. The results from pot experiment indicated that strain Fq7 had control efficiency of 62.71% to tomato bacte- rial speck. The strain was identified as Bacillus amyloliquefaciens according to its morphological, physiological and biochemical characteristics, and 16S rDNA sequence analysis. Strain Fq7 could colonize inside of tomato plant by inoculation of daubing leaves or pouring roots, and also could be recovered from leaves and stems, which meant the bacteria could move along the vascular bun- dles of the plant.