Epidemiological role of spontaneous weeds in the spreading of "bois noir" phytoplasma

urvival of Hyalesthes obsoletus on some weeds was investigated to verify their possible role in “bois noir” epidemiology. Data evidenced that H. obsoletus survived after 14 days of forced feeding on Urtica dioica, Convolvolus arvensis, Artemisia vulgaris, Plantago lanceolata and Taraxacum officinale. This evidence reinforced the hypothesis of a possible involvement of such weeds, carrying the same “bois noir” phytoplasma tuf-type identified in grapevines and insects, in “bois noir” spread in north-eastern Italy.