人参锈腐病拮抗菌的筛选鉴定及其生防效果

Screening and Identification of Antagonistic Strain and Its Biological Efficiency against Cylindrocarpon destructans

为了筛选出拮抗人参锈腐病菌(Cylindrocarpon destructans)的高效菌株,并研究其对人参锈腐病的防控效果,研究采用平板稀释法从人参根际土壤中分离获得菌株,以人参锈腐病菌为靶标菌采用平板对峙法筛选出拮抗活性较强的菌株;通过形态学特征、生理生化特征及16SrDNA序列分析对其进行鉴定;并测定其培养特性;通过田间试验测定拮抗菌对人参锈腐病的防治效果。结果发现菌株xf-11对人参锈腐病菌拮抗作用最强,抑菌率达到75.56%;经鉴定菌株xf-11为枯草芽孢杆菌(Bacillus subtilis);xf-11在12h进入生长稳定期,最适生长温度为37℃,最适生长pH为6~7;田间试验结果显示,xf-11处理的人参成活率达到90.5%,对人参锈腐病的防控率达到67.15%,明显高于对照组(CK)和多菌灵处理组(T2)(P<0.05)。以上结果表明,枯草芽孢杆菌xf-11对人参锈腐病菌具有较强的拮抗活性,能够有效防治人参锈腐病,具有潜在的应用价值。

This experiment was designed to obtain the efficient strains against Cylindrocarpon destructans,and explore their control effects on ginseng rust rot.The strains were separated from the rhizosphere soil of ginseng by the plate dilution method,and those with antagonistic activity were selected with the plate confrontation method.The pathogenic fungus Cylindrocarpon destructans was the target strain.The strains were identified based on morphological,physiological,biochemical characteristics and 16 S rDNA phylogenetic analysis,and the cultured characteristics of the antagonistic strain were measured.The control effects of antagonistic strain on ginseng rust rot were studied by field experiment.The results showed that strain xf-11 exhibited the strongest antagonistic ability to Cylindrocarpon destructans with inhibition rate of 75.56%,and strain xf-11 was identified as Bacillus subtilis.Strain xf-11 reached stable growth stage in12 hours,the optimal temperature was 37 ℃,and the optimal pH was 6-7.The results of field experimentshowed that the survival rate reached 90.5% in groups supplied with strain xf-11,and control rate of ginseng rust rot was 67.15%,which was significantly higher than that of CK and carbendazim treatments(P <0.05).In conclusion,the strain xf-11 showed high antagonistic activity against Cylindrocarpon destructans,and could effectively control the ginseng rust rot,and thus has potential application value.