Department of Biochemistry, Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Str.8, 07745 Jena, Germany.
Biodiversity project group, Department of Molecular Ecology, Max-Planck-Institute for Chemical Ecology, Hans-Knöll-Str.8, 07745 Jena, Germany.
Mol Ecol. 2014 Mar;23(5):1188-1203. doi: 10.1111/mec.12610. Epub 2014 Jan 22.
Although slugs and snails play important roles in terrestrial ecosystems and cause considerable damage on a variety of crop plants, knowledge about the mechanisms of plant immunity to molluscs is limited. We found slugs to be natural herbivores of Arabidopsis thaliana and therefore investigated possible resistance mechanisms of this species against several molluscan herbivores. Treating wounded leaves with the mucus residue ('slime trail') of the Spanish slug Arion lusitanicus increased wound-induced jasmonate levels, suggesting the presence of defence elicitors in the mucus. Plants deficient in jasmonate biosynthesis and signalling suffered more damage by molluscan herbivores in the laboratory and in the field, demonstrating that JA-mediated defences protect A. thaliana against slugs and snails. Furthermore, experiments using A. thaliana mutants with altered levels of specific glucosinolate classes revealed the importance of aliphatic glucosinolates in defending leaves and reproductive structures against molluscs. The presence in mollusc faeces of known and novel metabolites arising from glutathione conjugation with glucosinolate hydrolysis products suggests that molluscan herbivores actively detoxify glucosinolates. Higher levels of aliphatic glucosinolates were found in plants during the night compared to the day, which correlated well with the nocturnal activity rhythms of slugs and snails. Our data highlight the function of well-known antiherbivore defence pathways in resistance against slugs and snails and suggest an important role for the diurnal regulation of defence metabolites against nocturnal molluscan herbivores.
虽然鼻涕虫和蜗牛在陆地生态系统中起着重要作用，并对各种作物造成相当大的损害，但对植物抵御软体动物的机制知之甚少。我们发现鼻涕虫是拟南芥的天然食草动物，因此研究了该物种对几种软体动物食草动物可能的抵抗机制。用西班牙鼻涕虫 Arion lusitanicus 的粘液残留物（“粘液痕迹”）处理受伤的叶子会增加伤口诱导的茉莉酸水平，这表明粘液中存在防御激发子。在实验室和野外，茉莉酸生物合成和信号转导缺陷的植物受到更多的软体动物食草动物的损害，这表明 JA 介导的防御可以保护拟南芥免受鼻涕虫和蜗牛的侵害。此外，使用具有特定硫代葡萄糖苷类改变水平的拟南芥突变体进行的实验表明，脂肪族硫代葡萄糖苷在防御叶片和生殖结构免受软体动物侵害方面很重要。在软体动物粪便中发现了来自与硫代葡萄糖苷水解产物结合的谷胱甘肽的已知和新代谢物，这表明软体动物食草动物积极地解毒硫代葡萄糖苷。与蜗牛和鼻涕虫的夜间活动节律很好地相关，与白天相比，植物在夜间的脂肪族硫代葡萄糖苷水平更高。我们的数据突出了众所周知的抗食草动物防御途径在抵抗鼻涕虫和蜗牛方面的功能，并表明防御代谢物的昼夜调节在抵抗夜间软体动物食草动物方面起着重要作用。
