Determination of pathogenicity of some Bursaphelenchus species on different pine species in Duzce Forest District

The pinewood nematode, Bursaphelenchus xylophilus (Steiner and Buhrer) Nickle, (Nematoda: Parasitaphelenchidae) is a pest of conifer forest trees. This pest is characterized by the sudden death of infected pine trees. In this study, pathogenicty tests of six native Bursaphelenchus species (B. mucronatus, B. sexdentati, B. anamurius, B. vallesianus, B. andrassyi and B. hellenicus) on three pine species (Pinus slvestris, P. nigra and P. pinaster) under natural conditions were conducted. For each nematode species 8 trees were inoculated. In total for each tree species 96 trees (6 nematode speciesx8 treesx2 doses) were inoculated with nematodes. Also 8 trees for each tree species were used as control groups. Nematode inoculated trees were monitored for a year after inoculation. Monthyl oleoresin flow of each tree and other external symptoms (foliage coloration and Monochamus species activitity) were followed. At the end of the study, wood chip samples were taken from trees for extraction of the nematode and nematodes were counted in the laboratory. The results of pathogenicity tests were analyzed statistically. Nematode inoculated trees did not die a year after the date of inoculation. In addition no signs of insect infestations (especially species belonging to the family Cerambycidae and subfamily Scolytinae) were noticed on trees. The amount of oleoresin flow differed significantly among tree species. There was a significant difference on the oleoresin flow between B. sexdentati and B. anamurius inoculated tree species. However nematode doses did not affect the oleoresin flow significantly. According to the results of this study, inoculated Bursaphelenchus species into tree species under natural ecosystem conditions did not cause pathogenic effects.