一株对新月弯孢霉等香蕉病原真菌具有良好拮抗作用的菊欧氏杆菌

研究了香蕉内生菊欧氏杆菌(Erwinia chrysanthemi Burkholder,McFadden et Dimock)E353菌株对香蕉弯孢霉叶斑病菌新月弯孢霉Curvularia lunata(Wakker)Boedijn]等4钟香蕉病原真菌的抑制效果。对峙培养法和孢子萌发悬滴法检测结果表明，E353菌株对新月弯孢霉具有良好抑制效果。E353培养液滤液明显抑制靶标菌菌丝扩展，形成的抑菌带宽0.6cm；E353滤液使病原真菌芽管的生长点致畸膨大成串珠状，其半致死浓度EC50为4.48%(E353滤液的体积分数)。E353滤液对香蕉枯萎病菌香蕉镰刀菌、香蕉炭疽病菌芭蕉炭疽菌、香蕉链格孢叶斑病菌番茄链格孢亦有良好的拮抗活性，其EC50分别为6.14%、4.57%、7.59%。

An Strain of Erwinia chrysanthemi with Good Antagonisticity against CurvulariaLeafSpotPathogenofBanana

An endophytic strain of ErwiniachrysanthemiBurkholder,McFaddenetDimock,E353, was isolated from the pseudostem of banana, and its antagonistic action against Curvularialeaf spot (Curvularia lunata(Wakker) Boedijn) was tested by pairing culture and conidial germination of plant pathogens. The StrainE353culture broth evidently inhibited the spread of hyphas of the target pathogenic fungi, and inhibitive zones 0.6 cm wide were observed. The fermentation broth of the strainE353significantly inhibited conidial germination of C.lunata, and Colletotrichummusae(BerkeleyetMA.Curtis) vonArx, FusariumoxysporumSchlechtendahlf.sp.cubense(EF.Smith) SnyderetHansen, and Alternariaalternata (Fries) vonKeissler. Their EC50 were 4.48%, 6.14%, 4.57%, 7.59% respectively. The acting mechanism of this antagonistic strainE353showed that some cells of hyphas and spores became strings of beads.