Screening,Identification and Synergistic Effects of Biocontrol Bacillus for Cucumber Root Rot
Wu Guoping
Yang Lijuan
Zhang Chunxiang
Gao Wei
Jiang Yongcheng
Wei Yong
Liu Huiqin
Wang Yong
Abstract：Root rot caused by Fusarium fungi is very serious in cucumber growing areas in Tianjin.In this study,the healthy soil samples were collected from cucumber planting fields in 4 districts of Tianjin,and biocontrol strains for this disease were isolated by plate face-off method.Their antibacterial activity and syner-gistic effect were evaluated through mixing sterile filtrate and pot tests,and they were identified by morphologi-cal,physicochemical and molecular biological analyses.The results showed that 8 strains were isolated with good inhibition effect on Fusariumoxy sporum and F.solani,among them,the strains BL-29 and BL-40 showed more than 50％inhibition rate on the two pathogens.After compatibility tests,it was found that the strains BL-01,BL-09 and BL-21 had better compatibility,and their composite sterile filtrate had the inhibition rate on the two pathogens more than 68.5％and 71.6％respectively,which were significantly higher than those of the sterile filtrate from individual strain.The results of pot experiments showed that the composite suspension of the 3 strains had 67.6％of prevention effect on cucumber root rot disease,which was significantly higher than the suspension of individual strain(P＜0.05).The strains BL-09 and BL-21 were identified as Bacillus velezensis,and the strain BL-21 was as B.halotolerans through identification.The multi-component combina-tion of biocontrol bacteria had the potential of effective disease control.
Keywords：Cucumber root rotFusarium spp.BacillusSynergistic effectIdentification
Publication Date：2025-02-28
Online Publishing Date：2026-05-22(First online date of this platform, not the publication date of the document)
Pages：7( 134-140 )