南京地区蔬菜枯萎病菌拮抗细菌的筛选与评价

采集南京市郊常见蔬菜的根、根际和土壤样本97份,分离纯化后得到600个分离物,对其进行蔬菜枯萎病菌生长的抑制试验,获得拮抗作用明显的菌株237个,所占比例为39 50%。复筛后获得1 2 10、8 8、8 11等12个拮抗能力强且性能稳定的菌株,对枯萎病菌的抑菌圈直径为12～20mm。其中菌株8 8和菌株8 11能利用几丁质作为碳源。盆栽试验结果表明:12个菌株中有4个对番茄枯萎病有较强的抑制作用,防效为53 85%～73 08%,其中菌株8 8不仅能有效防治番茄枯萎病,而且对番茄苗有明显的促生作用。

Screening and Evaluation of Antagonistic Bacteria against Pathogen of Vegetable Fusarium Wilt in Nanjing District

Six hundred strains were isolated and purified from the roots and rhizospherium of common vegetables and the soil collected from the suburban districts of Nanjing.Antagonistic examination against Fusarium oxysporum revealed that 237 strains,ca. 39.5% of all tested strains showed antagonism.Twelve strains,whose radius of suppression cycles was between 12 mm and 20 mm,showed strong and steady antagonsim.Strain 8-8 and strain 8-11 grew well and produced clearing zone on colloidal chitin agar.In pot experiments four strains showed 53.85%-73.08% of control effect on tomato fusarium wilt and the strain 8-8 could also promote the growth of tomato seedling significantly.