Abstract:

The wood of artificially infected 3-year-old black pine,naturally infected over 15-year-old black pine and masson pine were extracted and purified elementarily by high pressure boiling and CHCL3/base Procedures.The results of bioassay by application of extracts to seedlings of black pine and masson pine indicated that wilting toxic compounds existed not in healthy pines and naturally infected pines which had died for 1 year,but in naturally and artificially infected pines which were still alive.After each of primary purified compounds was analyzed qualitatively by GC/MS System,benzeneacetic acid and 2-methoxycinnamic acid were found only in wilting toxic compounds and benzaldehyde was found in all compounds including toxic and non-toxic ones.Both benzeneacetic acid and 2-methoxycinnamic acid are phenolic compounds and important secondary metabolites in plants.It follows that wilting toxic substances related to benzeneacetic acid and 2-methoxycinnammic acid were abnormal metabolites synthesized in Bursaphelenchus xylophilus infected pines,and benzaldehyde was a normal metabolite of pines.

Key words: Pine wilt disease caused by pine wood nematodes, wilting toxic substance, extraction, analysis with GC/MS System