Evaluation of disease resistance of clones of Pinus massoniana to Bursaphelenchus xylophilus
The study was to evaluate the resistance of clones of Pinus massoniana to Bursaphelenchus xylo-philus through inoculation of Bursaphelenchus xylophilus.The results showed that the pine wilt was seriously accelerated in the greenhouse,while the response was not the same when inoculated of Bursaphelenchus xylophi-lus at high temperature and dry conditions,so pine species inoculated in greenhouse did not truly reflect the dis-ease resistance,and the best inoculation condition was in the field.The disease resistance of Pinus taeda was higher compared with other tree species,so it was chosen as the control species to identify resistance clones.The disease infection rates of all pine trees reached maximum after inoculated for 9 weeks in different inoculation con-ditions,so it was the best time to investigate and analyze the disease resistance of the trees.The disease resistance between candidate clones of P.massoniana was significant different.The average survival rate of candidate resis-tance families was 78.2%;the average survival rate of clones was 76%;the average survival rate of P.massoniana and P.taeda was 29.7% and 52.4%,respectively.The date showed that the resistance level of the clones of P.massoniana was 0.45 times higher than that of P.taeda,and 1.63 times than that of the common P.massoniana.