【摘要】 为筛选生防用放线菌，应用平板涂布法、划线分离法、琼脂块法和改良牛津杯法，从成县多个地区核桃根际土壤中分离和筛选出一株高抑菌活性的菌株KS7.结果表明菌株KS7对供试菌株大肠杆菌、金黄色葡萄球菌和枯草芽孢杆菌均具有较强的抑菌作用，其琼脂块对三株供试菌株的平均抑菌圈直径分别为31.25 mm、29.72 mm和35.10 mm;其无菌发酵液对三株供试菌株的平均抑菌圈直径分别为17.00 mm、19.17 mm和15.43 mm.根据该菌株的形态学观察、生理生化特性及16S rRNA序列分析，将菌株KS7鉴定为链霉菌属.更多还原

【Abstract】 In order to screen actinomycetes that can produce agricultural antibiotics, a strain KS7 with high antibacterial activity was isolated and screened from walnut rhizosphere soil in many areas of Chengxian county by spread plate method, plat streaking method, agar block method and improvement oxford cup method.The results showed that the strain KS7 had strong antibacterial effect on Escherichia coli,Staphylococcus aureus and Bacillus subtilis.The average antibacterial circle diameters of its agar block on the three strains were 31.25 mm, 29.72 mm and 35.10 mm, and the average inhibition zone diameter of the sterile fermentation broth against the three tested strains were 17.00 mm, 19.17 mm and 15.43 mm, respectively.According to the morphological observation, physiological and biochemical characteristics and 16 S rRNA sequence analysis, the strain KS7 was identified as Streptomyces.更多还原