Co-fermentated with Beauveria bassiana and Verticillium lecanii

Abstract:

[Objective] Both Beauveria bassiana and Verticillium lecanii are insecticide fungus for biological pest control in the using of study at home and abroad. In order to extend the scope and strengthen the effect of prevention and reduce the cost of biological pest control. co-fermentation have been applied in this investigation. [Methods] The feasibility of co-fermentation have been studied through comparing sporulation capacity, indoor antibiotic activities of two mixed strains. [Results] Results showed that the best ratio at 1:1 of Verticil-lium lecanii L-31 and Beauveria bassiana Q-55 by co-fermentation. Taked 10% from every inocu-lated in fermentation medium (Fermentation medium were prepared by yeast extract 5.0 g/L, glu-cose 20.0 g/L, malt extract 5.0 g/L, KH2PO4 3.0 g/L, millet 200.0 g/L, pH 6.5), 23.0 °C±0.1 °C fermentation temperature 12 d standed the total of spore-containing fermentation broth could reached 1 × 109 CFU/mL or more and have the stronger insecticide toxicity. It had inhibited effect on both Trialeurodes vaporariorum and Pieris rapae L. 9 d after treatment of the lethal concentration LC50 were 2.09×104±0.12 CFU/mL and 3.17×105±0.11 CFU/mL, broth con-centration 1×108 CFU/mL at the time of death in the LT50 was 2.11±0.14 d and 4.27±0.43 d, correct anti-greenhouse effect in the plot experiment more than 80%, having significant dif-ference with the single strain fermentation control effect. [Conclusion] It provides a scientific basis for further application of the two insecticidal funguses and a reference efficiency way for Spread-spectrum anti-fungal for spread spectrum efficiency of fungal biocontrol agents.