丹参根腐病菌拮抗菌株贝莱斯芽胞杆菌Bv1-4的筛选及盆栽防效

Screening of Antagonistic Isolate Bacillus velezensis Bv1-4 and Its Control Effect against Root Rot Disease on Salvia miltiorrhiza

为筛选防治丹参根腐病的高效生防菌,本研究通过平板对峙法,从健康丹参根际土壤中分离获得一株对丹参根腐病菌具有显著拮抗作用的生防细菌Bv1-4。结合细菌形态学、生理生化特征及序列分析,将菌株Bv1-4鉴定为贝莱斯芽胞杆菌Bacillus velezensis。该菌株对丹参根腐病菌层出、腐皮和尖孢镰刀菌的抑菌率分别为65.54%、68.28%和66.87%;进一步的抑菌谱测试表明Bv1-4对菜豆壳球孢、齐整小核菌、细极链格孢等多种植物病原菌均具有较好抑制作用。盆栽试验结果表明,接种Bv1-4后,丹参茎叶和根系鲜重较无菌水对照组均有显著提升,提升率分别为70.97%和70.37%;Bv1-4分别与丹参根腐病三种病原菌先后混合接种后,调查发病等级计算防效均可达80.00%以上。综上,Bv1-4生防性状优良,在植物病害生物防治中有较好应用潜力。

Root rot of Salvia miltiorrhiza is a common root disease caused by Fusarium spp.,which has become one of the primary diseases affecting the production of S.miltiorrhiza.In order to screen effective biocontrol bacteria against root rot disease of S.miltiorrhiza,a biocontrol bacteria Bv1-4 with significant antagonism was isolated from the rhizosphere soil of healthy S.miltiorrhiza by the plate confrontation test.Based on morphological,physiological and biochemical characteristics,and sequence analysis,isolate Bv1-4 was identified as Bacillus velezensis.The inhibition rates of Bv1-4 against root rot of S.miltiorrhiza were 65.54%,68.28%,and 66.87%for F.proliferatum,F.solani,and F.oxysporium,respectively.Further inhibition spectrum tests showed that Bv1-4 had a broad range of antifungal activity against various plant pathogenic fungi,such as Macrophomina phaseoli,Sclerotium rolfsii,Altrnaria tenuissima,and others.The results of the potted experiment proved that the fresh weight of above-and below-ground parts of S.miltiorrhiza after inoculation with Bv1-4 was significantly increased compared with the control group,and the increase rate was 70.97%and 70.37%,respectively;the control effect could reach more than 80%after mixed inoculation with Bv1-4 and three pathogens of S.miltiorrhiza root rot.In conclusion,Bv1-4 has good biocontrol characteristics and has good application potential in the biocontrol of plant diseases.