凤凰木重伞灵芝菌根腐病生防菌株的筛选及其发酵优化OA

[Objective]Bacteria antagonistic to Ganoderma multipileum that causes root rot on Delonix regia were identified,and their culture conditions optimized for biocontrol of the increasingly spread disease on the landscape ornamental trees.[Method]Using dual culture method,anti-G.multipileum microbes were isolated with taxonomic identities determined by morphological and molecular means.Conditions for culturing the isolates were optimized.In vitro control efficacy on the pathogen was examined by a pot experiment.[Result]The consortium of Strains FH-3 and FH-7,which were identified as Pseudomonas aeruginosa and Bacillus licheniformis,respectively,exhibited an inhibition rate of 72.80%against G.multipileum.In single-factor and orthogonal experiments,the culture of the mixed consortium was optimized to have a medium containing 3%of sucrose,0.5%of ammonium sulfate,1%of beef extract,and 2%of potassium chloride with 3%of inoculum to propagate under 32℃,pH 7,and constant stirring at 220 r·min-1 for 24 h.As a result,the inhibition rate on G.multipileum was raised to 88.70%.[Conclusion]The mixed FH-3 and FH-7 significantly inhibited the growth of G.multipileum,indicating a potential of developing the strains for controlling the root rot disease on D.regia.