棉花黄萎病菌拮抗细菌TUBP1的分离鉴定及其防病作用

为研制和开发新疆棉花黄萎病优良生防菌剂,采用琼脂平板扩散法,通过初筛和复筛,分离得到一株对棉花黄萎病菌(Verticillium dahliae)具有较强抑菌活性的拮抗菌株TUBP1。通过对形态观察、生理生化实验、16S rDNA和gyrB的基因序列分析,确定该菌株为Bacillus axarquiensis;利用生长速率法和牛津杯法分别测定了发酵液对棉花黄萎病菌抑菌活性,对棉花黄萎病菌菌丝生长抑制率为78.62%±3.48%,抑菌圈直径为21.00±3.86 mm。温室盆栽试验中,TUBP1最大生防效果为43.67%,小区试验中,TUBP1最大生防效果为43.07%。

Isolation,Identification, and Antifungal Activity of the Antagonistic Bacterial Strain TUBP1 against Verticillium dahliae Kleb.

The bacterial strain TUBP1, capable of strongly inhibiting Verticillium dahliae ATCC 36211, was obtained by preliminary and secondary screening using the agar plate diffusion method. It was characterized by morphological and cultural feature observation, physiological and biochemical experiments, and 16S rDNA and gyrB sequence analysis, and was identified as Bacillus axarquiensis. The in vitro antifungal activity of strain TUBP1 fermentation broth against V. dahliae was analyzed by growth rate and the Oxford cup method, revealing an inhibition ratio of (78.62 ± 3.48)% and inhabiting V. dahliae growth diameter of (21 ± 3.8) mm. In a greenhouse study, the biocontrol efficacy of strain TUBP1 against cotton Verticillium wilt was 43.67%, and this was also similar in a field experiment, at 43.07%. This is the first known report of the role of B. axarquiensis in preventing and curing cotton Verticillium wilt.