Identification of Antagonistic Bacterium W-7 Strain and Its Inhibition on Phytophthora infestans
WAN Anqi
JIANG Jizhi
SHA Haitian
LI Ying
WANG Beibei
JIN Xin
ZHANG Yahui
Abstract：The bacterium W-7 strain was isolated from diseased leaf of potato late blight, and showed obvious suppression on mycelia growth of Phytophthora infestans in lab. The purpose of this paper was to clear its classification status,inhibitory characteristics on P. infestans and the potential in control potato late blight. The traditional method combined with 16S rDNA sequence analysis were used for identification of W-7 strain,and dual culture method and punch method were applied for testing the inhibition effect of living strain,bacterial fluid and free-cell fermentation liquid of W-7 strain on P. infestans. And potato tuber slices method was employed for evaluating the prevention effect of bacterial fluid against late blight in vitro. The W-7 strain was identified as Bacillus pumilus based on colony feature,partial physiology and biochemistry characteristics,and 16S rDNA sequence analysis. Its fluid had the strongest inhibition effect (94. 44%) on pathogen mycelia growth compared with living strain and fermentation liquid. Especially, the inhibition rate and prevention effect on disease still reached 87. 65%and 73. 40%,respectively,after the bacterial fluid was diluted to 25% of initial concentration. It was observed that the bacterial fluid could cause deformation of P. infestans hyphae. W-7 strain,which belongs to Bacillus pumilus,has a great potential in controlling potato late blight in future.
Keywords：Phytophthora infestansantagonistic bacteriaBacillus pumilusidentificationinhibition effect
Publication Date：2017-01-01
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：6( 55-59,82 )