Study Of Fermentation Condationsand Preparation For Clonostachys Rosea QST-98

Clonostachys rosea QST-98is a strain obtained through mutagenesis, which is a type of high-performance biological control agents and also possesses many good features. It had better effects to prevent such as wheat scorch disease, soya bean sclerotium disease and tomato gray mold desease. In this paper, we filter out the Gliocladium roseum optimum fermentation medium, research the preparation process and prescription, try to develop the quality standards of the WP to reduce production costs and provide academic and application value for the industry.The study is based on the pre-screened fermentation medium and self-maded fermentation reactor, we want to optimize the solid-state fermentation condations. Single-factor research found that temperature, material thickness and hole density were the main factors. Then the solid-state fermentation condations were optimized by response surface experimentation and Box-Benhnken model. Results showed that the best fermentation conditions were:cultivation temperature24℃, initial pH7, material thickness3cm, hole density on fermentation reactor surface is0.74%, applying illumination and strain generation using the1-3generation. Finally, the yield of Clonostachys rosea sporulation was9.93×109spores/g medium and the fermentation time was10days, which highly reduce production costs.In this study, we also research the preparation process and prescription of Clonostachys rosea sporus wettable powder(WP). By researched the spore recovery methods, and break time, drying temperature and other process conditions, we derive the most suitable process conditions for bulk drugs spore powder. Through biocompatibility tests and single-factor test, we determine the optional agent types and general proportion. With the help of orthogonal test design of various additives, we obatain the final optimal formula:diatomaceous earth:spores=5:1, lignin sodium6%; sodium fluoresceinl%, spores broken tine20s, drying temperature35℃.At last, the performance indicators of Clonostachys rosea sporus wettable powder(WP) was studied. By studied the wetting time, the suspension rate, sifted rate, we find are all in line with the requirements of National Institute of Standards. The storage conditions are also studied, there is little effect on the performance indicators. Result showed that wetting time53.94s, suspension rate82.34%, sifting rate94.52%, moisture1.68%, the germination rate after45days storage is91.3%, which are all in line with the Chinese sandards.