甘蔗赤腐病菌拮抗细菌TWC2的分离鉴定及其防效研究

Isolation and Identification of Antagonistic Bacteria TWC2 and Its Control Effect Against Sugarcane Red Rot

由镰孢炭疽菌(Colletotrichum falcatum Went)引起的赤腐病是甘蔗生产上的主要病害之一,发病时可导致甘蔗产量严重损失。为探求赤腐病有效的生防措施,从热带牧草台湾草叶片上分离到一株生防菌TWC2。经形态观察、16S r DNA序列分析和生理生化鉴定,确定为解淀粉芽孢杆菌(Bacillus amyloliquefaciens)。平板对峙试验结果发现,TWC2菌株对甘蔗赤腐病菌(Colletotrichum falcatum)、香蕉黑星病菌(Macrophoma musae)、橡胶树炭疽病菌(Colletotrichum gloeosporioides)、柱花草炭疽病菌(Colletotrichum gloeosporioides)、芒果炭疽病菌(Colletotrichum gloeosporioides)、甘蔗环斑病菌(Leptosphaeria sacchari)、王草茎点霉叶斑病菌(Phoma herbarum)、西瓜枯萎病菌(Fusarium oxysporum)等病原菌均具有一定的抑制作用。离体叶片接种试验发现,TWC2菌株对甘蔗赤腐病菌的抑制率达72.01%,盆栽试验与离体叶片接种结果一致,表明TWC2菌株对甘蔗赤腐病具有较好的防治效果。该结论为开发甘蔗赤腐病生防方法打下了基础。

Sugarcane red rot is caused by Colletotrichum falcatum Went, and is one of the most devastating diseases of sugarcane, causing serious yield loss. An antagonistic bacterial strain TWC2 was isolated from the leaves of Taiwan grass （Zoysia tenuifolia Willd. ex Trin.）, a tropical grass, and used to control the red rot disease. The strain TWC2 was identified as Bacillus amyloliquefacieus through morphological observation, 16S rDNA sequence analysis, and physiological and biochemical identification. The plate confrontation test showed that the TWC2 had a strong antagonistic activity against the growth of some pathogenic fungi such as Colletotrichum falcatum, Macrophoma muscle, Colletotrichum gloeosporioides infecting Hevea brasilliensis, stylosanthes and mango, Leptosphaeria sacchari, Phoma herbarum and Fusarium oxysporum. In vitro leaf inoculation test showed that the TWC2 had an inhibition rate of 72.01% against C. falcatum, which was the same as the pot experiment. This conclusion indicated that TWC2 had a better control effect against the sugarcane red rot. The study laid a foundation for developing an effective biocontrol method to control the sugarcane red rot.