大白菜软腐病颉颃菌筛选及其发酵条件研究

Screen for Erwinia Carotovora Antagonistic Bacteria and Study on Its Fermentation Conditions

从大白菜软腐病的原位土壤中分离得到24株细菌,通过平板对峙法筛选得到2株具有明显抑制作用的菌株,分别命名为BRJ1和BRJ2。通过发酵条件试验表明:两种颉颃菌均为好氧菌;其中菌株BRJ1对数生长期为0～8h,在中性偏酸的环境下生长良好,适宜生长温度为30～35℃;菌株BRJ2对数生长期为4～13h,在pH值为4.5～9.5的条件下生长良好,最适生长温度为32℃。共同发酵时,应在中性环境,温度控制在32℃左右,定期翻堆以提供充足的氧气。

After isolation and purification,24 bacterial strains were obtained from insitu field.We found that 2 bacterial strains,named as BRJ1 and BRJ2,displayed apparent antagonistic effect to Erwinia carotovora through pairing culture.According to the fermentative condition experiment,BRJ1 and BRJ2 were regarded as aerobic bacterias.As for BRJ1,exponential growth phase ranged from 0~8h,the suitable pH was acid or neutral,and cultural temperture was 15~35℃.The exponential growth phase of BRJ2 were 4~13h,pH was from 4.5 to 9.5,and the optimum growth temperture was 32℃.When dealing with both two bacterial strains in common fermentation conditions,the neutral cultural environment such as pH=7.0 and temperture（32℃）were required.In additon,The manipulation of turning at regular intervals could provide sufficient oxygen for the course of fermentation.