松材线虫捕食真菌——少孢节丛孢HNQ11菌株初步研究

Preliminary Study of Strain HNQ11, a Pinewood Nematode Trapping Fungus

从海南岛香蕉根围土壤分离得到松材线虫(Bursaphelenchusxylophilus,PWN)捕食真菌HNQ11菌株,鉴定为少孢节丛孢(Arthrobotrysoligospora)。研究了HNQ11菌株的捕食作用及影响HNQ11捕食率的因素,结果表明,HNQ11菌株对松线虫表现出较好的捕食作用。HNQ11在含20g/L玉米粉的CMA培养基上捕食率最高;20￣28℃,pH6.5￣7.5条件下均能捕食松材线虫,25℃,pH6.5条件下捕食率最高,为87%;在不加入诱饵松材线虫或仅加入线虫洗液时不能产生捕食器官,在加入诱饵松材线虫和线虫磨碎液时能产生捕食器官,但线虫磨碎液诱导的菌环数比PWN诱导的菌环数少78%。

HNQ11, a fungus strain, was isolated from the soil around banana rhizosphere in Hainan Island, and found to trap pinewood nematode （PWN）. It was identified as A rthrobotrys oligospora based on its cultural phenoype, morphology characteristics and trapping device. After 3 days of incubation of HNQll on CMA, ＂baiting＂ PWNs were added to the plate. Sticky mycelia were observed 5 h later; mycelium loops emerged 15 h later; trapping network formed 24 h later. Once being attached by trapping facilities, the attach end of all the PWNs could not move while other parts of its body moved quickly for around 40 min. After that its activity slowed down gradually and 3 h later it lost its activity totally. The trapping efficiency amounted to the highest 48h after PWNs were added, and 144 h later the preyed PWNs were decomposed. Culture medium selection experiment revealed that HNQ11 showed the highest preying rate on 20 g/L CMA with a suitable temperature ranging from 20℃ to 28℃ and suitable pH value from 6.5 to 7.5. No trapping device was produced when only fresh water or rinsing water from PWN was added to the plate. Although trapping device was also induced by grinded PWN, the number of mycelium loops was 78 % less than that induced by live PWN.