鞭式达丁屯氏菌对捻转血矛线虫感染性幼虫及秀丽隐杆线虫作用的动态观察

Observation on dynamics of Duddingtonia flagrans against infective larvae of Haemonchus contortus and free-living nematode Caenorhabditis elegans

用光学显微镜和扫描电镜研究鞭式达丁屯氏菌对捻转血矛线虫感染性幼虫(L3)和秀丽隐杆线虫的动态作用。将鞭式达丁屯氏菌接种在0.2g/L玉米粉培养基中,培养7d后,加入试验线虫,在虫体刚被捕捉时即开始记为0h,此后分别于第1、2、3、4、6、8、12、16、20、24、36和48小时取样观察。结果显示,该菌培养后可自发形成捕食结构;加虫30min后即有虫体被捕捉;捕捉后第4小时,菌丝侵入秀丽隐杆线虫导致死亡,而捻转血矛线虫L3被菌丝侵入致死亡则需要20~24h;捕捉后第24小时,整个秀丽隐杆线虫被菌丝侵占并完全消化;而捻转血矛线虫L3则需要36h被菌丝完全侵占,48h被完全消化。以上结果为进一步探讨捕食线虫性真菌的杀虫机理提供科学依据。

Reaction dynamics of nematode-trapping fungus Duddingtonia flagrans against infective larvae(L3)of Haemonchus contortus and free-living nematode Caenorhabditis elegans was investigated using optical and scanning electron microscopy.D.flagrans was inoculated onto 0.2g/L corn-meal-agar Petri dishes.After 7days,L3 and C.elegans were added into the Petri dishes,and the samples consisting of L3-fungi and C.elegans-fungi were collected at 0,1,2,3,4,6,8,12,16,20,24,36 and 48h,where 0hwas the time when a bait nematode was initially captured by the fungus.In result,D.flagrans predation structures were spontaneously formed;L3or C.elegans was captured by the fungus after 30 min.After 4h,C.elegans was penetrated by the fungus leading to rapid death.20~24hwas needed for the fungus to invade the L3.After 24 h,the whole body of C.elegans was occupied and digested entirely by the hyphaes.The complete occupation of the body of L3 occurred at 36 hand the nematode was completely destroyed within48 h.The results above provided a scientific basis for further exploring the mechanism of interactions of nematode-trapping fungi with nematodes.