番茄叶霉病拮抗菌AYM-18抗菌物质的初步研究

目的]探讨对番茄叶霉病具有较强抑制作用的拮抗菌AYM-18的抗菌物质,为利用该菌开发环境友好型的生物农药应用于番茄生产奠定基础.方法]采用滤纸片法测定拮抗菌AYM-18的全细胞培养液、无菌滤液和菌体悬浮液对番茄叶霉病病原菌的抑菌活性,确定其抗菌物质的主要来源,并采用单因子试验测定其抗菌物质的稳定性及产生条件.结果]拮抗菌AYM-18的全细胞培养液、无菌滤液对番茄叶霉病菌的抑菌效果明显,产生的抑菌带较早、较大;AYM-18菌株无菌滤液在pH 5～9、-20～80℃时均表现出很强的抑菌活性.AYM-18菌株抗菌物质产生的最佳培养条件为：培养基初始pH 6、接种量5％、28℃条件下培养36h.结论]拮抗菌AYM-18对番茄叶霉病菌的拮抗作用源于其代谢物质,其抗菌物质具有一定的酸碱稳定性和热稳定性,产生条件温和,具有开发成生防制剂的潜力.

Primary report on the antibacterial material of strain AYM-18 against tomato leaf mould

Objective]The antibacterial material of strain AYM-18 against tomato leaf mould was explored in order to provide references for developing an environmental-friendly microbial pesticide to be used in tomato production.Method]The inhibitory effects of the component of antagonistic strain AYM-18 were tested using fermented liquid,bacteria suspension and its aseptic filtrate to identify the main source of the antibacterial material.Meanwhile a single factor experiment was conducted to test its stability and fermentation condition.Result]The results showed that the fermented liquid and aseptic filtrate had high inhibitory activity,and their inhibition zones were wider and earlier than other treatments.The inhibitory activity of the aseptic filtrate was very strong in 5-9 pH values and-20 to 80 ℃ temperatures.The optimized conditions of the antagonistic substance were the initial pH of 6,the inoculation amount of 5％,and duration of 36 h at 28 ℃.Conclusion]The antibacterial material of strain AYM-18 against tomato leaf mold was the metabolic substances.It has high stability against heat and acid,and its produce condition is very mild.So it is expected to be a new biological fungicide.