中文摘要：

采用稀释分离法和组织分离法，获得白僵菌105株，初步筛选出20株有效菌株，测定其发酵液对4种靶标线虫的生物活性。结果表明：20株被测菌株中有9株对不同种类线虫表现出较高的生物活性。其中菌株B703147发酵液处理南方根结线虫和大豆胞囊线虫二龄幼虫24h校正死亡率均为92％以上，具有较高应用价值；其次菌株B23对南方根结线虫和大豆胞囊线虫致死率也均为85％以上；供试菌株中B703148对水稻干尖线虫活性最高，处理48h致死率为66．15％，而大部分菌株对小杆线虫致死率均达到80％以上。研究表明不同白僵菌菌株的发酵液对同一种类线虫生物活性存在差异，对不同种类线虫存在选择性毒力差异。

英文摘要：

By means of dilute-separate technique and tissue-separate technique, 105 isolates of Beauveria were seperated from insects and soil samples. 20 isolates with strong bio-activity to Heterodera glycines were screened firstly, then their bio-activity were mensurated against to Meloidog＇yne incognita, Heterodera glycines, Aphelenchoides besseyi and Caenarhabditis sp.. The results showed that 9 strains that were screened from 20 isolates had strong effects on different nematode species. Be treated with fermentation filtrate of strain B703147 for 24h, the corrected mortality rate of Meloidog＇yne incognita and Heterodera glycines were higher than 92.00%, After 48h, the lethal rate of strain B23 against to Meloidogyne incognita and Heterodera glycines reached to higher than 85%. The activity of strain B703148, which lethal rate reached to 66.15% after 48h, was the highest than other strains against to Aphelenchoides besseyi, Then lethal rates of most strains against to Caenarhabditis sp. reached to higher than 80%, There were significant differences among different Beauveria strains bio-activity against the same nematode species, and the selective toxicity of different nematode species differed from each other too.