芽胞杆菌ZKY01防控花生果腐病研究

Study on the Bio-Control Efficiency of Peanut Pod Rot by Bacillus ZKY01

【目的】镰刀菌复合感染引起的花生果腐病是广东花生重大土传病害,严重影响花生的产量和品质。针对花生果腐病筛选出生防菌并对其开展鉴定、生理生化测试和田间防控效果评估,以期为花生果腐病绿色防控提供理论依据。【方法】采用平板拮抗法从实验室保存的生防芽胞杆菌中筛选对花生果腐病病原菌具有广谱拮抗活性的菌株,然后结合16S rDNA、gyrA和gyrB序列扩增结果和系统发育分析开展菌株鉴定,并测定菌株的生理生化指标和Biolog-GN板碳源利用能力,利用MSgg、BGM1、BGDM培养基测定菌株的生物被膜形成能力,并通过大田小区试验测定菌株的田间防病效果。【结果】生防菌株ZKY01对花生果腐病病原菌Fusarium sp.G15、F.oxysporum R5和F.solani R4.2具有较好的广谱拮抗活性,平板抑菌率分别为72.23(±3.36)%、54.14(±10.33)%和69.37(±2.17)%;系统发育分析结果显示,菌株ZKY01为贝莱斯芽胞杆菌(Bacillus velezensis),该菌能在3%~10%NaCl溶液中正常生长,生长温度范围为10~50℃,能利用50种碳源;能在MSgg、BGM1和BGDM液体培养基上形成稳定的薄皮。田间防效测试结果显示,ZKY01可湿性粉剂苗期淋施,对镰刀菌引起的花生果腐病防治效果达到95.14%。【结论】贝莱斯芽胞杆菌ZKY01在镰刀菌引起的花生果腐病生物防治中具有较大的应用潜力。

【Objective】Pod rot caused by Fusarium spp.is a major soil-borne peanut disease in Guangdong,which affects the yield and quality of peanut seriously.In order to provide a theoretical basis for green prevention and control of pod rot,a biocontrol bacterium was screened and its identification,physiological biochemistry characteristics and control efficiency in fields were evaluated.【Method】Strains with wide amitbacterial spectrum activity the pathogens of peanut pod rot were screened from biocontrol Bacillus strains preserved in laboratory by plate antagoinsm method,and identified by sequence amplification and phylogenetic analysis of 16S rDNA,gyrA,and gyrB sequences.Then,their physiological and biochemical characteristics,carbon source utilization capacity of Biolog-GN plate,biofilm formation in MSgg,BGM1,and BGDM media were determined.Meanwhile,the control effects of these strains on peanut pod rot were conducted by field plot tests.【Result】A Bacillus strain ZKY01 with wide antibacterial spectrum activity was selected,and its plate inhibition rates on Fusarium sp.G15,F.oxysporum R5 and F.solani R4.2 were 72.23(±3.36)%,54.14(±10.33)%and 69.37(±2.17)%,respectively.According to the phylogenetic analysis,the strain ZKY01 was identified as Bacillus velezensis.ZKY01 could grow normally in 3%to 10%NaCl solution,and temperature suitable for its growth ranged from 10℃to 50℃.It could use 50 kinds of carbon sources and form robust pellicles on MSgg,BGM1 and BGDM liquid media.Field control test results showed that ZKY01 wettable powder drenching at seedling stage had a control effect of 95.14%against Fusarium-caused peanut pod rot.【Conclusion】Bacillus velezensis ZKY01 has great application potential in the biological control of peanut pod rot caused by Fusarium spp.