Transmission of the pine wood nematode <i>Bursaphelenchus xylophilus</i> through oviposition activity of <i>Monochamus galloprovincialis</i> (Coleoptera: Cerambycidae)

Transmission of Bursaphelenchus xylophilus (PWN) by the oviposition of Monochamus galloprovincialis was studied in Portugal. Female insects laid eggs on 77% of pine bolts on the laboratory, of which 37% became infected with PWN, with a mean of 290 nematodes. Inside the PWN affected zone 50 P. pinaster trap-trees were created between May and September 2001 and 2002, of which 29 were colonised by M. galloprovincialis and only four became infected by the nematode. The low transmission efficiency detected both on laboratory and field suggests that nematode transmission through the vector’s oviposition activity may be a secondary component of the pine wilt disease epidemiology in Portugal.