The Effect on Fungal Diseases of Antagonistic Streptomyces sp.182-2 and Primary Identification of the Antibiotic Substance

A study was carried out on the inhibition effects of fermented broth of Streptomyces 182-2.The results showed that fermented broth of the strain 182-2 was of superior and stable inhibition effect on Alternaria alternata and of wide inhibition spectrum against various pathogens.The inhibition rate of fermented broth to tobacco brown spot in detached leaves was 65.79%.The protective and therapeutic inhibition rates to tobacco brown spot in greenhouse were 60.01% and 47.37%,respectively.The crude extracts of antibiotic substance of strain 182-2 expressed obvious inhibition effect to mycelia growth and the inhibition rate was 64.6% on the 7th day(with the concentration of crude extracts being 1000μg/ml).When the pathogen spore was treated by the crude extracts,spore germination rate reduced in earlier stage,tube and hypha grew in abnormal shape as shorten,twist and big sac in later stage.By means of antibiotic special identification technique including the paper chromatography of eight kings of solvent system,pH chromatography and paper electrophoresis,strain 182-2 was indicated to produce basic water-soluble substances.