【目的】 筛选出对草地贪夜蛾Spodoptera frugiperda高致病性的球孢白僵菌Bb378，并进一步研究菌株对玉米生长的影响及对草地贪夜蛾的驱避效果，为应用球孢白僵菌防治草地贪夜蛾奠定基础。【方法】 分别用0.05% Tween-80水溶液和1 × 10⁴、1 × 10⁵、1 × 10⁶、1 × 10⁷和1× 10⁸ 孢子/mL的球孢白僵菌孢子悬浮液接种草地贪夜蛾3龄幼虫，第3、7及14天后观察记录感染情况及死亡虫数；分别用浸种法、灌根法、叶面喷施法研究球孢白僵菌Bb378菌株对玉米的促生性及对草地贪夜蛾取食行为的影响。【结果】 筛选出的高致病性菌株Bb378处理草地贪夜蛾3龄幼虫14 d后累计校正死亡率为48.61%，LC₅₀为1.11×10⁸孢子/mL。使用叶面喷施法接种，球孢白僵菌Bb378对玉米叶面积和鲜重的影响最大；使用灌根法和浸种法接种，Bb378菌株对株高的影响较为明显；当Bb378浓度为1×10⁷ 和1×10⁸孢子/mL时对玉米的促生长效果较为显著。浓度为1×10⁷ 和1×10⁸孢子/mL悬浮液浸种对初孵和3龄幼虫均具有显著的驱避效果；1×10⁷ 和1×10⁸孢子/mL悬浮液灌根对初孵幼虫驱避效果明显，但对3龄幼虫仅在1 ×10⁸孢子/mL浓度下有明显作用；叶面喷施法与对照差异不显著。【结论】 球孢白僵菌Bb378对草地贪夜蛾具有较高致病性，接种后促进了玉米生长，形成的球孢白僵菌Bb378-玉米共生体可抑制草地贪夜蛾的取食行为，具有进一步研究和开发的价值。

[Objectives]  To investigate the potential of using the fungus Beauveria bassiana to protect maize crops from Spodoptera  frugiperda, a polyphagous, important, invasive, insect pest, that poses a major threat to agriculture in China. [Methods]  The Beauveria bassiana Bb378 strain, which is highly pathogenic to S. frugiperda, was isolated and 3rd instar S. frugiperda larvae were inoculated with a 0.05% Tween-80 aqueous solution containing either 1 × 10⁴, 1 × 10⁵, 1 × 10⁶, 1 × 10⁷, or 1 × 10⁸ conidia/mL of B. bassiana spore suspension. The infection rate and number of dead larvae were observed and recorded after 3, 7 and 14 days. Effects of the Bb378 strain on the feeding of S. frugiperda on maize were studied by using the seed soaking, root irrigation and foliar spraying methods. [Results]  After 14 days the cumulative corrected mortality and LC₅₀ of the highly pathogenic Bb378strain were 48.61% and 1.11 × 10⁸ conidia/mL, respectively. Spraying the Bb378 strain onto maize foliage increased the leaf area and fresh weight of corn, whereas root irrigation and seed soaking had an obvious  effect on plant height. The growth promoting effect of the Bb378 strain was obvious at concentrations of 1×10⁷ and 1×10⁸ conidia/mL. Soaking seeds in suspensions of 1×10⁷ and 1×10⁸ conidia/mL significantly repelled newly hatched and 3rd instar larvae. Irrigating roots with suspensions of 1×10⁷ and 1×10⁸ conidia/mL also had an obvious repellent effect on newly hatched larvae, but only a concentration of 1×10⁸ conidia/mL significantly repelled 3rd instar larvae. There was, however, no significant difference between leaf spraying and the control. [Conclusion]  The Bb378 strain is highly pathogenic to S. frugiperda. Applying B. bassiana to maize not only promoted plant growth, but also inhibited the feeding behavior of S. frugiperda, findings that justify further research and development.