解淀粉芽孢杆菌BaA-007鉴定及其对苹果腐烂病的抑制作用

从苹果韧皮组织分离获得1株潜在的生防菌菌株。基于形态和16S rDNA、gyrA鉴定其为解淀粉芽孢杆菌（Bacillus amyloliquefaciens），命名为BaA-007（中国农业微生物菌种保存中心，菌种编号：ACCC60382）。该菌株及其次生代谢物对苹果腐烂病菌（黑腐皮壳菌，Valsa mali）生长具有抑制作用，离体条件下可显著降低腐烂病病斑的扩散速度。以BG培养基为基础培养基，筛选其最佳培养条件为蔗糖0.5%、细菌学蛋白胨1%、硫酸二氢钾0.1%、温度36 ℃、pH 7.0。BaA-007处理后，苹果水杨酸（SA）响应性基因PR1、PR2和NPR1，茉莉酸（JA）响应性基因PDF1.2、CORONATINE INSENSITIVE 1（COI1）和AOS，乙烯（ET）响应性基因ETR1、ERF1和HEL以及几丁质合成酶B基因（Chitnase B，ChiB）在接种处理后的不同时间点均上调。综上所述，菌株BaA-007对苹果腐烂病有显著的拮抗效果，有望作为防治苹果腐烂病制剂开发的生防菌株。

Identification of Bacillus amyloliquefaciens BaA-007 and its Inhibitory Effect on Apple Canker

In order to search for new microbial resources to antagonize Valsa canker of apple，a potential biocontrol strain was isolated and purified from the phloem tissue by a flat-panel test in this study. The strain was identified based on its colony，strain morphology，16S rDNA and gyrA gene sequence. The strain was identified as a Bacillus amyloliquefaciens，named as BaA-007（Agricultural Culture Collection of China，preservation number：ACCC60382）. We further confirmed the strong antifungal activity of the strain and its secondary metabolism to Valsa mali. Results showed the strain and its secondary metabolites could inhibit the growth of Valsa mali，and significantly reduced the spread rate of the rot spots. Based on BG medium，the best cultural condition was 0.5% sucrose，1% bacteriological peptone，0.1% potassium dihydrogen sulfate，pH 7.0 and temperature 36 ℃. After inoculation of BaA-007，the salicylic acid（SA）- responsive genes PR1，PR2 and NPR1，the jasmonic acid（JA）-responsive genes PDF1.2，CORONATINE INSENSITIVE 1（COI1）and AOS，the ethylene（ET）-responsive genes ETR1，ERF1 and HEL，as well as Chitin synthetase B genes were all upregulated at different points. Above all，the strain BaA-007 had a good antagonistic effect on Valsa canker，and it was expected to be used as a biocontrol strain to prevent apple Valsa canker.