一株桑树内生细菌的鉴定和对桑椹核地杖菌的拮抗作用  

Identification of a Mulberry Endophytic Bacterium and Its Antagonistic Activity on Scleromitula shiraiana

作　　者：谢洁[1] 任慧爽 唐翠明[2] 左伟东[1] 陈洁[1] 黄传书 王振江[2] 戴凡炜[2] 周泽扬[1,4] 

机构地区：[1]西南大学生物技术学院,家蚕基因组生物学国家重点实验室,重庆400715 [2]广东省农业科学院蚕业与农产品加工研究所,广州510610 [3]重庆市蚕业科学技术研究院,重庆400700 [4]重庆师范大学生命科学学院,重庆400047

出　　处：《蚕业科学》2015年第5期815-824,共10页ACTA SERICOLOGICA SINICA

基　　金：教育部留学回国人员科研启动基金项目(No.教外司留2015-311);西南大学基本科研业务经费专项(No.XDJK2-014C155);家蚕基因组生物学国家重点实验室开放课题(No.SKLSGB2013025);广州市民生科技专项(No.2014Y2-0051)

摘　　要：桑椹菌核病是由桑椹核地杖菌（Scleromitrula shiraiana）等病原真菌引起的果桑毁灭性病害。寻获对桑椹菌核病病原菌有拮抗作用的桑树内生菌,可以达到通过安全、长效的生物防治方法控制病害的目的。以生产上对桑椹菌核病抵抗力较强的桑树品种川7637为材料,采用组织分离法从其健康植株的茎中分离获得一株对桑椹核地杖菌具有显著拮抗作用,且对桑树组培苗有促生作用的内生细菌7PJ-16菌株。基于7PJ-16菌株的形态、生理生化特性及16S rDNA系统发育分析结果,将其鉴定为特基拉芽孢杆菌（Bacillus tequilensis）,命名为Bacillus tequilensis 7PJ-16。抑菌谱测试结果表明B.tequilensis 7PJ-16菌株96 h发酵滤液对10种植物病原真菌具有不同程度的抑制作用,其中对桑椹核地杖菌的抑菌率高达100%,且发酵滤液的热稳定性强。对B.tequilensis 7PJ-16菌株培养特性的初步研究表明,该菌株的最适生长温度为25℃,培养96~120 h的发酵滤液对桑椹核地杖菌的抑菌率可达100%。田间防效试验的初步结果显示,在桑树花期喷施5次B.tequilensis 7PJ-16菌株的发酵上清液,其病果率仅为1.83%,较清水对照处理组降低18.66个百分点。综上研究表明,筛选获得的桑树内生细菌B.tequilensis7PJ-16菌株对桑椹核地杖菌有较强的拮抗作用,是开发桑椹菌核病生防制剂较为理想的候选菌株。Sclerote disease of mulberry fruit,which is caused by several fungal pathogens including Scleromitrula shiraiana,is a destructive disease in mulberry fruit production. Safe and long-term effective biological control of the diseasecan be realized through finding out the mulberry endophytes which have antagonistic activity on the pathogens of mulberry fruit sclerote disease. Using tissue isolation method,one mulberry endophytic bacterial strain7PJ-16 was obtained from the healthy stems of mulberry variety Chuan 7637 with high resistance to mulberry fruit sclerote disease. It has obvious antagonism on S. shiraiana and can promote the growth of cultured seedlings of mulberry. Based on morphological features,physiological and biochemical characteristics and 16 S rDNAphylogenetic analysis result,7PJ-16 strain was identified to be Bacillus tequilensis and named as Bacillus tequilensis 7PJ-16. The test results of antimicrobial spectrum showed that 96 h fermentation broth of 7PJ-16 strain had various degrees of antagonistic effect on 10 plant pathogens and had excellent thermal stability. Among them,the inhibitory rate of the fermentation broth of B. tequilensis 7PJ-16 on S. shiraiana was up to 100%. Furthermore,preliminary study on cultural characters of B. tequilensis 7PJ-16 showed that the optimal growth temperature of B. tequilensis 7PJ-16 was 25 ℃,and S.shiraiana can be completely inhibited by the fermentation filtrate of 7PJ-16 after being cultured for 96 to 120 h. The preliminary field control experiment results showed that after spraying the fermentation supernatant of B. tequilensis 7PJ-16 on mulberry for 5 times at the flowering time,the diseased fruit rate was 1. 83%,being reduced by 18. 66 percentaee points compared with the clean water control group. The above results indicated that mulberry endophytic bacterium B. tequilensis7PJ-16 has strong antagonistic activity on S. shiraiana,being an ideal candidate strain for developing the biological control agent against sclerote disease of mulberry fruit.

关 键 词：桑树内生菌 特基拉芽孢杆菌 桑椹核地杖菌 拮抗活性 

分 类 号：S888.7[农业科学—特种经济动物饲养]