贝莱斯芽孢杆菌HYN-9的分离、鉴定及其对花生白绢病的生防作用OA北大核心CSTPCD

This study aimed to obtain bacterial strains with high antagonistic effects against Scle-rotium rolfsii.In total,18 bacterial strains were isolated from Scutellaria baicalensis residue by plate coating method.Among these strains,HYN-9 exhibited the most robust antagonistic activity against S.rolfsii,with an inhibition zone width of 10.92 mm.The strain HYN-9 was identified as Bacillus velezensis based on morphological,physiological and biochemical characteristics,and 16 S rDNA se-quencing.The culture filtrate of HYN-9 potently inhibited the hyphal growth of S.rolfsii with an inhibition rate of 70.01%,and also had a strong inhibitory effect on the formation and germination of sclerotia.In addi-tion,the volatile compounds produced by strain HYN-9 inhibited the growth of S.rolfsii with an antibacteri-al rate of 88.79% .Pot experiment showed that HYN-9 significantly reduced the incidence rate and index of infection to peanut southern blight with the efficacy of 73.23%,which was significantly higher compared with carbendazim medicament(47.62%,P<0.05).Meanwhile,HYN-9 improved the activity of plant defense enzymes such as phenylalaninase(PAL),polyphenol oxidase(PPO),and peroxidase(POD),and so that enhanced the systemic resistance of the peanut plant against diseases.This study demonstrated that the strain HYN-9 possesses strong antagonistic effect against S.rolfsii,and has potential to be developed as biocontrol agents for peanut southern blight.