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.

• 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。