Liquid-solid Dual-phase Fermentation of Metarhizium anisopliae

Metarhizium anisopliae is an important pest-pathogenic fungus.This experiment carried out liquid-solid dual-phase fermentation of M.anisopliae MA4-37,and researched the effects of liquid medium,solid medium,shallow tray solid fermentation,bagged solid fermentation and solid medium thickness on fungus growth and sporulation,to optimize and control of fermentation process.The screening result showed that liquid culture medium B(soybean 1%,sugar 1%,NaCl 0.5%,and MnSO4 0.5%,with KH2PO4-K2HPO4 buffer adjusting the pH value to 6.0-7.0) was more suitable for liquid fermentation,with which conidia production and mycelial growth amount both reached the highest,4.3×109 conidia/L and 5.99 g/L,respectively.At the stage of solid fermentation,the effect of shallow tray fermentation was better than bagged fermentation.Under shallow tray fermentation,when solid culture medium F(rice 300 g,broken rice 600 g,H2O 50%,KH2PO4-K2HPO4 buffer 0.05%,sucrose 0.5%) with thickness of 1.3 cm was employed,the sporulation capacity(dry spore powder) was up to 16.1 mg/g after 7-day culture.