[Objective] To optimize solid-state fermentation and sporulation conditions for Beauvena bassiana.[Method] The orthogonal experiment was adopted to optimize the fermentation conditions including substrate water content,medium thickness and the inoculation.The optimal sporulation conditions include illumination,temperature and air relative humidity.[Result] It is demonstrated that temperature is an important factor influencing accumulation of biomass of B.bassiana during solid state fermentation.The result suggested that optimized temperature combination of lag phase,exponential phase and stationary phase is at 24-26 ℃,27-28 ℃ and 28-29 ℃,respectively,and under this condition,the maximum biomass reached 279.32 mg mycelium per gram of dry weight of substrate 120hr after fermentation.Furthermore,the effects of water content and thickness of solid substrate,and proportion of liquid inoculum and solid substrate on solid-phase fermentation was investigated using the method of orthogonal design (L9 (34)),and result suggested that all three factors remarkably influenced the growth of B.bassiana in solid-phase fermentation,the order of factors according to influenced extent is substrate thickness ＞ water content ＞ proportion of liquid inoculum and solid substrate.However,there was no remarkable difference among three factors each other.Statistical analysis suggested that the optimized parameter of solid-phase fermentation is 8cm of culture thickness,0.4 L/kg of proportion of liquid inoculum and solid substrate and 55％-60％ water content of substrate.In addition,the conditions of sporulation for solid culture substrate was studied,and the result indicated that under the condition of continuous daylight lamp irradiation,25 ℃ of the temperature and 63％ of relative humidity,the highest yield of conidia reached 1.57 × 1010 conidia per gram dry weight substrate,which increased by 35.34％ comparing with that of other solid state fermentor used in our country.[Conclusion] The study will provide theoretical basis for industrialization of solid fermentation of Beauveria bassiana.%[目的]优化球孢白僵菌固态发酵及产孢的最佳条件.[方法]采用正交试验优化固态发酵时的发酵基质含水量、培养基厚度和接种量,并研究了产孢时的光照条件、温度及空气相对湿度.[结果]温度是影响固体发酵生物量积累的重要因素,优化的发酵温度组合为延滞期24～26℃、对数生长期27 ～28℃和稳定期温度28 ～29℃,发酵120h可达到最大生物量(279.32 mg菌体/g干重基物).发酵基质含水量、培养基厚度、接种量3个因子对球孢白僵菌菌体生长的影响都达到极显著水平,各因子的主次关系大小为培养基厚度、发酵基质含水量、接种量,但各因子之间差异不显著.优化的发酵条件参数为:培养基厚度8 cm,接种量0.4 L/kg,发酵基质含水量55％～60％.对发酵基物的产孢条件研究表明,在连续光照、温度为25℃、相对湿度为63％时产孢量达最高(1.570×1010个孢子/g干发酵产物),比国内同类研究的产孢量提高了35.34％.[结论]为球孢白僵菌固态发酵的产业化提供了理论依据.
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