AN EFFECT OF PINE VOLATILES ON DEPARTURE OF BURSAPHELENCHUS-XYLOPHILUS (NEMATODA, APHELENCHOIDIDAE) FROM MONOCHAMUS-ALTERNATUS (COLEOPTERA,CERAMBYCIDAE)

To clarify the effect of the volatiles of Pinus densiflora on the temp oral pattern of departure of Bursaphelenchus xylophilus from Monochamu s alternatus adults (nematode departure curve), autoclaved or normal p ine twigs were provided to the beetles. Monoterpenoids were not detect ed from the air of rearing containers with autoclaved pine twigs. A Ko lmogorov-Smirnov test showed that there were significant differences i n the averaged nematode departure curve between the 2 beetle groups su pplied with different foods. The time of 50% nematode departure was sh orter in the beetles supplied with autoclaved twigs. The proportion of nematodes which remained in the bodies of 51-day-old M. alternatus wa s significantly smaller in the beetles supplied with autoclaved pine t wigs. Consequently, it is suggested that B. xylophilus had a trait of spontaneous departure from M. alternatus and that the volatiles from e xcised normal P. densiflora twigs repressed B. xylophilus departure fr om M. alternatus.