【摘要】 昆虫病原真菌白僵菌Beauveria spp.是害虫生防产品研发的主要真菌之一，其生长及产酶特性是高毒力菌株筛选的重要依据。本研究对15株分离自麻天牛僵虫的白僵菌进行了鉴定，并对其生长、产孢以及胞外水解酶活性进行了测定分析。rDNA-ITS序列进化关系分析结果显示，15株白僵菌中11株为球孢白僵菌B.bassiana,4株为硫酸白僵菌B.sulfurescens。不同温度及培养基条件下菌株生长与产孢分析结果表明，25℃,PPDA培养基适合大部分白僵菌的生长，温度下降至20℃时各菌株产孢量更高；CN004、CN011、CN012及CN055菌株为产孢优势候选菌株，其中CN055菌株产孢量可达到(1.99±0.57)×10~6个/mm~2。胞外水解酶活性测定结果表明，CN006、CN012、CN040及CN055的几丁质酶活性较强，且几丁质酶活性呈现先上升后下降趋势，培养至第5天酶活性最高。CN009、CN019、CN040及CN055菌株的蛋白酶活性较强，蛋白酶活性呈现先急剧上升、再平缓上升的趋势，CN055菌株第9天的酶活性为(472.5±0.39) U/mL,显著高于其他菌株(P<0.05)。CN040和CN055菌株在产孢、产几丁质酶和蛋白酶能力上兼具优势，可作为后续研发的重点菌株。更多还原

【Abstract】 The entomopathogenic fungus Beauveria spp. is one of the most important fungal genera for the development of biocontrol agents. Growth and enzyme production traits are key indicators for selecting high-virulence strains. In this study, 15 Beauveria strains were isolated from naturally infected Thyestilla gebleri and identified via rDNA-ITS sequence analysis. Among them, 11 strains were identified as B. bassiana, and four as B.sulfurescens. The effects of temperature and media on fungal growth and sporulation were evaluated. Most strains exhibited optimal growth at 25℃ on PPDA medium, while sporulation peaked at 20℃. Strains CN004, CN011, CN012 and CN055 exhibited superior sporulation, with CN055 producing up to(1.99±0.57)×10~6 conidia/mm~2. Extracellular enzyme activity assays showed that CN006, CN012, CN040 and CN055 had strong chitinase activity, which peaked on the 5th day after inoculation before declining. CN009, CN019, CN040 and CN055 showed high protease activity, with a sharp initial increase followed by a slower rise. On the 9th day, CN055 displayed the highest protease activity(472.5±0.39 U/mL), significantly higher than other strains(P<0.05). In summary, CN040 and CN055 demonstrated superior traits in terms of sporulation and hydrolytic enzyme production, making them promising candidates for future development of fungal biopesticides.更多还原