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Single factor test and orthogonal test students with a broad spectrum of antagonism within Bacillus amyloliquefaciens TB2 strain fermentation medium and fermentation conditions were studied. The results showed that the optimal medium component: corn starch 1.0%, soybean meal 1.0%, (NH4) 2SO4 0.5%, MgSO4 · 7H2O 0.1%, FeSO4 7H2O 0.03% K2HPO4 · 3H2O 0.02%, KH2PO4 0.01%; culture conditions: pH value of 7.5 (pre-consumer), temperature 35 ° C, 3% of the inoculum size, loading volume of 50 mL / 250 mL flask, shaking speed 200 r · min-1, fermentation period 22 to 26 h. Optimum conditions, the level of fermentation reached 8.52 × 1010 cfu · mL-1. TB2 as the starting strain, fermentation parameters according to the optimization of the fermentation medium and conditions, changes in the strain 180 L and 270 L fermentation tank fermentation process of exploration. Ultimately determine the the strain TB2 optimum fermentation conditions: initial pH value of 7.5 to 3% inoculum was inoculated into the fermenter, 45% of the liquid volume V, the oxygen was 30%, temperature 30 to 33 ° C. The fermentation process by measuring the change of the pH value, the cell concentration, reducing sugars, amino nitrogen and sporulation rate, the optimum discharge tank for about 32 h. Optimized conditions fermentation level of 3.0 ~ 6.5 × 1010 cfu · mL-1, sporulation rate of 90%. The fermentation broth Fusarium banana anthracnose fungus, Botrytis cinerea, Fulvia fulva antagonistic test results show that the fermentation broth of four plant pathogens have a certain inhibitory rate of 29.5% to 45.2%. Process after the fermentation broth directly spray drying method TB2 original powder. Measured indicators of the quality of the original powder. The results show that the number of viable cells 20 billion / g contamination rate ≤ 3% Loss on drying 4.5% to 7%, the pH value of 6.0 ~ 7.5,80% to 90% by 75 microns Test sieve, at room temperature and six months storage at 4 ℃ viable rate of more than 90%. TB2 sinensis were prepared 1:500,1:1 000,1:1 500,1:2 000-fold dilution banana storage diseases, pepper mining the consequences and pepper seedling blight pot control test. The test results show that the original powder TB2 strains banana storage period axis rot, anthracnose, Phytophthora capsici has a preventive effect. 1:500 effect of treatment group, banana-axis rot and anthracnose control effect of 34.32% to 66.32% and 62.42% to 73.90%, 61.51% to 76.39, pepper the postharvest and pepper seedling blight as % and 63.30% to 86.60%. The TB2 strains Processing disease can inhibit the rate of expansion, delayed onset. In addition, TB2 agents on pepper seedlings better promoting effect. Pharmacodynamic evaluation and safety of the strains in this study provide a basis for the rational use of technology.
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