Study Of Clonostachys Rosea S920 Solid Fermentation Conditions And Preparation

Clonostachys rosea S920 is an ideal biofungicide with high disinfection efficiency, strong specificity and long-term biological control activity. But many problems exist in production and application which have not been resolved, so it can not be made good use in agriculture and its further development is restricted. Our goal is to optimize the solid-fermentation conditions and prepare Clonostachys rosea spores wettable powders which is a novel and important fungal microbial pesticide. To provide theoretical basis for future industrial production, we studied the quality about the Clonostachys rosea spores wettable powders.Firstly, we studied and optimized the solid fermentation conditions of Clonostachys rosea, including fermentation temperature, thickness of medium, hole density and initial pH. We used the response surface method to optimize the formulation. Results showed that the best fermentation conditions:fermentation temperature is 24℃, thickness of medium is 3cm, hole density is 2cm and initial pH is 7, which not only shorten the fermentation time but also improve the yield of Clonostachys rosea sporulation. Then we studied how to prepare the wettable powders, and optimized the formulation of the wettable powder, including the ratio of the carrier, various additives and spore powder in the wettable powers. We used the response surface method and got the best formulation which consists of 20% of spores,65% of diatomite,2% of sodium dodecyl benzene sulfonate,12.5% of ligninsulfonate and 0.5% of sodium carboxymethyl cellulose. Lastly, we prepared wettable powders according to the formulation and investigated its quality, including the wettability, suspension rate, fineness, moisture content and other indicators. The results showed that the wetting time of the wettable powder is less than lmin, suspension rate is more than 75%, the sieving rate through 325 mesh sieve is greater than 90% and the moisture content is less than 2%. All the indicators of the wettable powders are up to the national standards. And we also preliminarily studied its storage stability.