香蕉枯萎病拮抗细菌对4种土传植物病原真菌的抑制作用

Effect of Antagonistic Bacteria Inhibiting Fusarium oxysporum on Four Soil-born Plant Pathogens

测定了从果园土壤中分离的4株香蕉枯萎病拮抗细菌对粉蕉根腐病菌（Pythium.sp）、辣椒白绢病菌（Sclerotium rolfsli）、节瓜枯萎病菌（Fusarium oxysporumf．sp．binincasae）的抑菌效果以及对香蕉枯萎病的防治效果。结果表明，3种拮抗细菌bio-B3、bio-d4和bio-P对4种病菌的生长具有显著的抑制作用，产生明显的抑菌带，拮抗细菌bio-d5对辣椒白绢病菌不产生抑菌带，但对其他3种病菌均产生明显的抑菌带；4种拮抗菌株对节瓜枯萎病菌和香蕉枯萎病菌孢子萌发具有显著的抑制作用，其发酵原液对病菌孢子萌发的抑制率较高，抑制率为76．4％-100％，随着稀释倍数的增加，其抑制效果逐渐降低；拮抗细菌bio-B3、bio-d4、bio-d5发酵液100、200和300倍稀释液对香蕉枯萎病的防治效果为53．3％-80．2％，它们之间无显著性差异，但显著大于bio-P和恶霉灵的防治效果。

Four antagonistic strains isolated from the soil of orchards were tested in their inhibitive activity and controlling efficacy on Pythhun sp., Sclerothtm rolfiii., Fusarium oxysporum f. sp. Binincasae and Fusarium oxysponan f. sp. cubense. The results showed that three antagonistic bacterial strains （bio-d4,bio-B3 and bio-p） were of significant inhibition against four plant pathogenic fungi,forming apparent inhibitive zones,and the antagonistic strain bio-d5 was not of inhibition against Sclerotium rolfsii, but was of inhibition against other plant pathogens. And four antagonistic strains were of significant inhibition against spores germination of Fusarium.m oxysporum f.sp. binincasae and Fusarium oxysporum f.sp. cubense ,and the inhibitive effect was gradually reduced with the increasing of diluted fold of fermentation solution of antagonistic bacteria.The control efficacy of 100,200 and 300-fold diluted fermentation solution of antagonistic strains bio-d4,bio-d5 and bio-B3 were between 53.3% and 80.2% ,being significantly stronger than the efficacies of antagonistic strain bio-p and chemical hymexazol.