松材线虫与其携带细菌之间的相互影响

Mutual Influences Between Bursaphelenchus xylophilus and Bacteria Carries

笔者研究了从松材线虫体上分离的2 株强致病菌和1 株弱致病菌与松材线虫的相互影响。结果表明:强致病菌荧光假单胞菌(Pseudomonas fluorescens) GcM5 1A菌株、恶臭假单胞菌(Pseudomonas putida)ZpB1 2A菌株能够明显地促进无菌松材线虫的产卵量增加、繁殖速度加快和成虫虫体生长;同时,松材线虫也能促进强致病菌荧光假单胞菌GcM5 1A菌株、恶臭假单胞菌ZpB1 2A菌株的繁殖。而泛菌(Pantoea sp.)ZM2C菌株完全抑制了无菌松材线虫的繁殖,无菌松材线虫对泛菌ZM2C菌株的繁殖亦具有显著抑制作用。由此说明松材线虫与其携带的某些致病菌之间存在互惠共生现象,松材线虫携带的致病菌并不是偶然的污染,它们之间的互惠共生现象是在长期共生进化中形成的。笔者还讨论了互惠共生现象在松材线虫致病过程中的作用。

The interactions were studied between pine wood nematode (Bursaphelenchus xylophilus)and three bacterium strains isolated from the nematode,which are two strong-pathogenic bacterium strains(Pseudomonas fluorescens) GcM5-1A and (P. putida) ZpB1-2A,and a weak-pathogenic bacterium strains,(Pantoea sp.)ZM2C.The result showed that the strong-pathogenic (P. fluorescens) GcM5-1A strain and (P. putida) ZpB1-2A strain significantly increased fecundities,reproduction rate and the adults’body volume of pine wood nematode.Meanwhile,pine wood nematode significantly promoted reproduction of the two strong-pathogenic bacterium strains.However,weak-pathogenic bacterium strains,(Pantoea sp).ZM2C,completely inhibited reproduction of pine wood nematode.Aseptic pine wood nematode significantly inhibited reproduction of the strain ZM2C (Pantoea sp.).The results indicated that mutualistic symbiosis existed between pine wood nematode and some pathogenic bacteria carried.The phenomena showed that the pathogenic bacteria carried by the nematode were not accidentally contaminated,rather than symbionts with pine wood nematode coevoluted for a along time.The part of mutulistic symbiosis playing in the process of pine wilt disease was discussed.