Abstract:

Bursaphelenchus xylophilus is different from B. xylophilus in pathogenicity and distribution. Whether the two species can be crossed and what is different in pathogenicity between the likely offspring and the parents are important information for taxonomy, epidemic, and control of the disease. The hybridization was conducted between 5 isolates of B. xylophilus from different countries and one isolate of B.mucronatus from China. The results showed that all nematode isolates of B. xylophilus were successfully crossed with the isolate of B. mucronatus and the rate of hybridization was relfative high, but parts of the hybrid offspring were not able to survive. The hybrid offspring and their parents were inoculated in pines of two-year-old Pinus massoniana. The results also showed that the pathogenicity of hybrid offspring was weaker than their parent nematodes, and the numbers of offspring nematodes reisolated from pines were significantly less than their parents.

Key words: Bursaphelenchus xylophilus, Bursaphelenchus mucronatus, hybridization, pathogenicity