Aggregation of Bursaphelenchus lignicolus (Nematoda : Aphelenchoididae) to Several Compounds Containing Oleyl Group

Abstract

Aggregation of Bursaphelenchus lignicolus to several compounds containing oleyl group was investigated. Pads of absorbent cotton were placed in the center of petri dishes containing agar. The nematodes reared on the colonies of Botrytis cinerea were released on the pads. Round, polyethylene pieces, one left untreated and the other two or three treated with different test chemicals, were evenly laid around the center, with the treated faces against the agar. After incubation in darkness at 25°C for 5 days, the nematodes under the pieces were counted. The differences among the treatments were statistically analysed using 10 or 20 replicates. 1-Monoolein exhibited a significant attracting effect, but hydrogenation, epoxidation and trans isomerization of the cis double bond caused the effect to disappear. Ethylene glycol monooleate, which has one hydroxyl group instead of two, exhibited an activity some-what lower than that of 1-monoolein. Oleic acid and oleyl alcohol were also active, but definitely inferior to 1-monoolein. Oleoyl amide was not active. Under the pieces treated with oleylamines, a large number of dead nematodes accumulated, probably due to their toxic effect.