甲醇介导昆虫与植物的防卫反应

The defence and antidefence between plant and herbivore mediated by methanol

综述甲醇介导的昆虫与植物的互作关系。害虫为害使寄主植物释放大量甲醇。这是由于害虫唾液的碱性性质提高了果胶甲基酯酶的活性,上调了果胶甲基酯酶基因的转录,水解果胶而即时释放出大量甲醇。果胶甲基酯酶则可能通过改变细胞壁结构特性而间接激发茉莉酸和水杨酸信号途径,从而启动植物防卫物质如胰蛋白酶抑制剂的合成。此外,甲醇还可能作为信号物质,影响害虫定向。外施甲醇于健康植物则可能通过负反馈机制抑制植物防卫反应,从而影响植食者。

The defence and antidefence between plants and herbivores mediated by methanol were reviewed. Plants produced and released large quantities of methanol when attacked by herbivores. During feeding on leaves, the oral secretions from herbivore resulted in a pH shift at the wound site, and subsequently increased the transcript accumulation and activity of leaf pectin methylesterases （PMEs）. PMEs subsequently hydrolyzed pectin to release methanol. PMEs also contributed, probably indirectly by affecting cell wall properties, to the induction of jasmonic acid and salicylic acid, and triggered synthesis of anti- herbivore substances such as trypsin proteinase inhibitor. In addition, as a volatile, methanol may influence host orientation by herbivore. Moreover, methanol application to health plant decreased anti- herbivore substances, probably through negative feedback, and consequently affected herbivore performance.