Primary data from phytotests on seedlings: specificity of nematodes of the genus Bursaphelenchus to different host plants

   The specificity of three species of nematodes of the genus Bursaphelenchus: B. willibaldi (Fungivorus), B. ulmophilus (Hoffmanni), B. michalskii (Eggersi) to three species of woody plants: Picea abies, Acer platanoides, Fraxinus excelsior was tested in laboratory conditions. The test was aimed at identifying the vector-independent specificity of nematodes to host plants. The experiment was conducted on indoor seedlings under laboratory conditions. Nematode isolates were stored in the live culture bank of the Zoological Institute of the Russian Academy of Sciences. The worms were cultured in a sterile culture of the fungus Botrytis cinerea before the test was set up. As an inoculum for infecting the seedlings, 200 individuals of the same species of nematodes at different developmental stages were used per plant. The experiment was conducted at 21–23 °C for 45 days. The parameter for successful reproduction is the excess of the final nematode population over the inoculum. The species B. willibaldi demonstrated survival on all three experimental plant species, but no excess of nematodes compared to the inoculum was recorded. B. ulmophilus survived on P. abies and A. platanoides. B. ulmophilus was not detected on F. excelsior. B. michalskii was not detected in any of the infested plants 45 days after inoculation. This indicates that this nematode species is not able to survive on the plant species represented. The probability of vector-independent specificity of the three submitted nematode species to the tested range of plants is low.

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