【摘要】 BC98 Ⅰ是一株分离自沤肥浸渍液的拮抗菌株 (Bacilluscereus) ,它的发酵液对黄瓜枯萎病具良好防治效果。它分泌产生的抗真菌物质的粗提物对黄瓜枯萎病菌有很强的拮抗作用。该物质对高温高压、紫外线和蛋白酶均不敏感 ,同时 ,在中性偏碱的条件下活性较高。抑菌机制试验表明 :它可造成孢子萌发率降低、菌丝生长形态异常。粗提物经丙酮沉淀后得到的沉淀也对黄瓜枯萎菌有较好拮抗作用 ,且对高温高压和紫外线不敏感 ,可认为是粗提物的进一步纯化物。更多还原

【Abstract】 Antagonist strain BC98-I ( Bacillus cereus )shows strong inhibition to cucumber wilt disease.The crude extraction of antifungal substance produced by the bacterium has obvious inhibition effect on Fusarium oxysporum (Schl.) f.sp. cucumerinum Owen.The crude extraction is stable to autoclave,ultraviolet,trypsin and proteinases K.At pH 7.0～8.0,it has the strongest antifungal activities.The inhibition mechanism experiment indicates that it cause the decrease of spore germination rate and the abnormal hyphal growth.The crude extraction precipitated by Acetone also has obvious inhibition effect on pathogen and is stable to autoclave and ultraviolet.更多还原