不同致病力松材线虫的繁殖能力和移动能力比较

Comparison on Fecundity and Migration Ability of Bursaphelenchus xylophilus with Different Virulence

通过黑松和马尾松接种明确不同松材线虫虫株的致病力,进而对不同致病力虫株的繁殖力、移动能力等生物学特性进行了比较。研究结果表明,虫株AMA3C28和USA的致病力显著强于C14-5和OKD-1,AMA3C28和USA接种35 d后,黑松枯萎率均达100%,而马尾松枯萎率分别为75%和20%;C14-5和OKD-1对黑松和马尾松无致病作用或有极弱的致病作用。接种35 d后,AMA3C28和USA在黑松苗内的增殖能力显著强于C14-5和OKD-1。在灰葡萄孢培养条件下,AMA3C28和USA的繁殖力、雌雄性别比例显著高于OKD-1;强致病力虫株AMA3C28和USA雌成虫尾部均为指状钝圆,而弱致病力虫株OKD-1和C14-5雌成虫中分别28%和2%尾部具有尾尖突。AMA3C28和USA在黑松茎段内迁移能力显著强于C14-5和OKD-1。因此,松材线虫在树体内的繁殖力及移动能力可能与其致病力有关。

The virulence of different strains of Bursaphelenchus xylophilus was determined by challenging with Pinus thunbergii and P. massoniana. The strains with different virulence were screened and their biological characteristics were compared.Strains AMA3 C28 and USA were more virulent than C14-5 and OKD-1. The wilting ratio on P. thunbergii was 100% for35 d after inoculation with AMA3 C28 and USA,while on P. massoniana were 75% and 20%,respectively. C14-5 and OKD-1 had no or very weak pathogenicity on both P. thunbergii and P. massoniana. AMA3 C28 and USA proliferated rapidly in P. thunbergii seedlings 35 d after inoculation,which was significantly higher than that of C14-5 and OKD-1. The fecundity of AMA3 C28 and USA was significantly higher than that of OKD-1 and C14-5 when feeding on B. cinerea. The sex ratio of male and female in AMA3 C28 and USA was significantly higher than that in C14-5 and OKD-1. Difference was also observed in tail morphology of adult female between virulent and avirulent strains when feeding on Botrytis cinerea.For strong virulent strains( AMA3 C28 and USA),100% adult females had no terminal mucro. However,about 28% of adult females of OKD-1 had terminal mucro and 2% of adult females of C14-5 had terminal mucro. The migration ability of AMA3 C28 and USA in the stem segment of P. thunbergii was higher than that of C14-5 and OKD-1.