假单胞茵YT3和枯草芽孢杆菌DZl的发酵罐生长条件优化

假单胞菌（Pseudomonas sp．）YT3和枯草芽孢杆菌（Bacillus subtilis）DZl是从植物根际土壤筛选出的具有应用潜力的植物根际促生细菌。研究发酵罐中接种量、转速、通气量等因素对YT3菌量以及对DZl芽孢率、菌量的影响。结果表明：不同的接种量、转速和通气量对Pseudomonas sp．YT3的活菌数、Bacillussubtilis DZl的活菌数及芽孢率均有显著影响。10％的接种量、2m3／ll的通气量对YT3和DZl菌株的作用效果与15％的接种量、3m3／h相当，但显著高于5％的接种量和1m3／h。当转速为200r／min时，YT3具有最高的活菌数，DZl具有最高的活菌数和芽孢率。综合分析认为，YT3和DZl发酵罐的最佳条件为接种量10％、转速200r／min和通气量2矗m。

On the Optimization of Growth Conditions of Pseudomonas sp. YT3 and Bacillus subtilis DZ1 in Fermentation Cylinders

Pseudomonas sp. YT3 and Bacillus subtilis DZ1, isolated and screened from the plant rhizo-sphere soil, were plant growth-promoting rhizo-bacteria exhibiting broad application prospects in the bio-fertilizer production. Taking YT3 and DZ1 bacterial strains as research objects, the experiment were conducted to study the influence of inoculation quantity, rotating speed and minute ventilation on the bacteria population and spore rates of YT3 and DZ1 in the fermentation cylinders. The results indicated that different inoculation quantity, rotating speed and minute ventilation could have significantly effects on the bacteria population and spore rates of YT3 and DZ1. Effects of the 10% inoculation quantity and 2 m3/h ventilation were similar on the bacteria population and spore rates of YT3 and DZ1 with that of the 15% inoculation quantity and 3 m3/h ventilation, however, their effects were higher than that of the 5% inoculation quantity and 2 m3/h ventilation. The numbers of YT3, as wellas the numbers and the spore rates of DZ1 reached the highest under 200r/min rotating speed. As a result, the optimum fermentation cylinder conditions of YT3 and DZ1 were 10% inoculation quantity, 200 r/min rotating speed and 2 m3/h ventilation.