温度和 pH 对捕食性线虫真菌分离株少孢节丛孢菌生长的影响及生物学特性观察

摘要

The influence of pH value and temperature on the growth of a nematode-trapping fungus, Arthrobotrys oligospora ,was studied.The hyphae of this isolated strain,A.oligospora,were inoculated in 0.4 g/L corn meal agar medium (CMA),cultured under the temperature of 15,20,25,30 and 35 ℃,respec-tively.Meanwhile,the hyphae were also cultured in 0.4 g/L corn meal agar medium with pH value of 5.5, 6.0,6.5,7.0,respectively.The growth status of the strain and the length of its mycelia were observed ev-ery day.The results showed that the fungus could grow with the pH value of 5.5~7.0 and temperature of 15~35 ℃ ,and that its hyphal growth rate was the highest when cultured with pH value of 6.0 and tem-perature of 25 ℃.In addition,the biological characteristics of A.oligospora was described.Its conidiophores was unbranched,erect,hyaline and separate,the conidium was fasciculate,pyriform to obovate,single sepa-rate and hyaline conidia.This organism traps nematodes by triaxial adhesive nets formed on lateral stalks. The findings above provides an important foundation for further study on the biological characteristics and the mass cultivation of A.oligospora.%为了观察捕食性线虫真菌少孢节丛孢菌(Arthrobotrys oligospora )的生长及 pH 值和温度对该菌生长的影响，试验将分离株少孢节丛孢菌丝接种于0.4 g/L 玉米粉琼脂培养基(CMA)中，分别置15、20、25、30、35℃恒温箱中培养，又将菌种分别接种到 pH 值为5.5、6.0、6.5、7.0的0.4 g/L 玉米粉琼脂培养基，每天定时观察菌株的发育情况，测量菌丝生长长度.结果表明：A.oligospora 在 pH 值为5.5~7.0的环境下均能生长，其中以 pH 为6.0时生长速度最快；在温度为15~35℃时均能生长，其中以25℃时菌丝生长速度最快.此外，对真菌分离株生物学特性进行了描述和图片说明，特征为：分生孢子梗无色、直立、不分枝、分隔，分生孢子丛状着生、无色、具1个隔、梨形至倒卵形，捕食线虫的器官为三维粘性网.上述结果为进一步研究 A.oligospora 的生物学特性及批量化培养奠定了重要基础.