布氏白僵菌微菌核的诱导培养及条件优化

Induction and culture condition optimization of Beauveria brongniartii for microsclerotial production

菌核是一些丝状菌的休眠结构,具有很强的抗逆性和稳定性。近年来发现有些虫生真菌在特定的营养条件下能形成微菌核(MS)。以适合用于地下害虫防治的布氏白僵菌为对象,研究观察了该菌摇瓶培养微菌核形成的过程,通过单因子实验和部分因子实验确定培养液的碳源A、碳氮比B和接种量C为影响MS产量的显著因子,而装液量和转速是不显著因子;通过最陡爬坡实验和中心组合实验得出MS摇瓶培养参数的最优二次多项式回归模型,确定在A=30.66g/L,B=7.59:1,C=1.03%时,MS产量理论最大值为最高(8.24×103MS/mL),MS实验产量在8.00–8.25×103MS/mL,优化的结果产量比初始试验时的最大值提高21%–25%。研究结果为探索使用布氏白僵菌菌核防治地下害虫奠定了基础。

Sclerotium is a dormant structure of some hyphomycetes with high resistance ability and stability in soil. In recent years, it was found that microsclerotia （MS） of some entomopathogenic fungi formed under special culture condi- tions. Beauveria brongniartii is an important entomopathogenic fungus mainly for soil pest control. In the present study, formation of MS by B. brongniartii in shake culture was observed, and the indices of carbon source （A）, carbon-nitrogen rario （B） and inocula amount （C） were determined to be significantly important factors, while the initial inoculation vol- ume and rotation speed were not important. By a steepest ascent design and a central composite design, an optimal culture model was determined, which resulted in a maximum MS production of 8.24×10^3MS/mL, while A=30.66g/L, B=7.59：1 and C=1.03%. A optimization test resulted in a MS production of 8.00-8.25×10^3MS/mL, 21%-25% higher than the maximum yield produced in the initial test. The data of this study will benefit the potential application of B. brongniartii MS for soil pest control in the future.