银耳杨梅霜病发病机理及其病原菌抗菌谱的测定

Pathogenicity Mechanism of Yang Mei Shuang Disease on Tremella fuciformis and Inhibition Spectrum of the Pathogenic Bacterium

以银耳杨梅霜病发病菌筒为试材,采用平板培养及分子生物学方法,研究了杨梅霜病病原菌的生物学特性及抗菌谱。结果表明:分离到3株病原菌Js-1T、Js-2、Js-3的形态特征和培养特性相同,16SrDNA酶切带型完全一致,三者为重复菌株;回接试验证实Js-1T菌株为杨梅霜病的病原菌;对峙培养试验表明,Js-1T菌株产生的抗菌物质抑制香灰菌和银耳菌丝的生长;16SrDNA序列分析表明,Js-1T菌株与链霉菌属菌株Streptomyces hebeiensis strain NBRC 101006T的同源性最高为97.62%。结合形态特征和分子生物学分析,证明Js-1T菌株属于链霉菌属。同时测定了Js-1T菌株的抗菌谱,其对大肠杆菌的抑菌圈直径为2.76cm,对枯草芽孢杆菌的抑菌圈直径为1.26cm;对真菌核盘菌、有害疣孢霉菌、稻瘟菌、木霉、根霉的抑菌圈直径分别为4.29、4.07、3.85、3.37、2.90cm。此外,对镰刀菌和香蕉枯萎病菌天蓝一号也具有一定的抑制作用。

Taking Tremella fuciformis artificial bed-log which was infected with Yang mei shuang disease as materials,plate cultivation and molecular biology methods were used to study the biological characteristics and antibacterial spectrum of pathogenic bacterium.The results showed that the colonies characteristics and cultural characteristics of the three pathogen strains Js-1T,Js-2and Js-3were the same as PDA culture.And the 16 SrDNA of three strains had the same bands after digestion.,so these strains were repeated strains.Strain Js-1T was confirmed to be the pathogen of this disease through Koch＇s rules.Strain Js-1Thad strong inhibition on xiang hui and tremella gemma,which could be the cause of the disease.16 SrDNA squence analysis showed that strain Js-1Thad the highest similarity with Streptomyces hebeiensis strain NBRC 101006 T,reaching 97.62%.The results of cultural characteristics and molecular biological analysis showed that strain Js-1Tbelonged to Streptomyces.What＇s more,the antibacterial activity of strain Js-1T was determined.The results showed that strain Js-1T had strong inhibition against these tested strains.The diameters of Escherichia coli and Bacillus subtilis were 2.76 cm and 1.26 cm,respectively.The diameters of Sclerotinia sclerotiorum,Mycogone perniciosa,Pyricularia grisea,Trichoderma viride,Rhizopus stolonir were 4.29,4.07,3.85,3.37 and 2.90 cm,respectively.In addition,strain Js-1T had antibacterial activity to Fusariumspp and Banana vasicular wilt.