松材线虫病感病松树中致萎毒性物质的研究

本研究用我国自然感染松材线虫病的15年生以上黑松和马尾松以及人工感染松材线虫病的3年生黑松的木质组织进行萃以和粗提纯，方法为高压蒸煮法和氯仿碱法。生物测定结果显示，有致萎活性的毒性物质仅存在于自然感病未死的黑松和马尾松以及人工感病未死的黑松木质组织中。自然感病死后1年的黑松和马尾松以及健康松树不中含有这些毒性物质。通过气相色谱－质谱联用仪（GC／MS System）对上述木质组织萃取物作定性分析发现，自然感病未死的黑松、马尾松和人工感病未死的黑松有致萎活性的萃取物中均含苯乙酸和2－甲氧基肉桂酸，自然感病死后1年的松树和健康松树中则无。而在健康松树和感病松树中都发现有苯甲醛存在。表明毒性物质与苯乙酸和2－甲氧基肉桂酸有关，苯甲醛则是松树正常的代谢产物。苯乙酸和2－甲氧基肉桂酸均为酚类化合物，是植物体内重要的次生物质。说明感病松树中的毒性物质是松树组织由于松材线虫侵染而产生的异常代谢产物，应称之为致萎毒性物质。

STUDIES ON WILTING TOXIC SUBSTANCES PRODUCED IN PINES INFECTED BY PINE WOOD NEMATODES

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.