Studies On Screening, Identification And Fermention Liquor Activity Of Antagonistic Bacterium Against Fulvia Fulva In Tomato

This experiment had studied four aspects, which include separation and selection of the antagonistic strains, Identification of the antagonistic strain, ferment condition optimization and physical and chemical properties of active material in Fermented liquid. The test results as follows:1. This experiment had been isolated58strains from soil bacteria with the method of dilution separation. We filtered out6antagonist role strains through the test of living bacterium body antagonism resistance. Then we determined the resistance of six strains’fermentation liquid, and numbered S46as the best antagonist role strain. And the strain antimicrobial spectrum determination, the results showed that the strains antibacterial wide spectrum, including the tomato leaf mold pathogen antagonism is best, the zone of inhibition up to27mm.2. The identification of morphological, physiological and biochemical reactions and molecular had been identified S46strain as Burkholderia gladioli.3. This experiment had improved fermentation optimization medium fordium and fermentation conditions of S46strain, and improved its production rate. Finally the culture medium was determined as Soybean meal15g/L, corn flour5g/L, sucrose15g/L, K2HPO410g/L, the fermentation condition6%, the bottle of30mL/250mL, initial pH7.5, speed180rpm, temperature35℃, fermentation time72h.4. The test result on the active material of S46fermention liquor:The thermal stability of S46fermention liquor is high.,except that,theUV and sunlight stable still better. It is Sensitive to strong acid and strong base, and the active interval of ph is6-10. the activity is lost in organic solvents,and array of inhibition zone is:Acetone>methanol>ethanol>benzene>n-butyl alcohol>chloroform.