Leiss Kirsten A, Choi Young H, Abdel-Farid Ibrahim B, Verpoorte Robert, Klinkhamer Peter G L
Institute of Biology, Leiden University, The Netherlands.
J Chem Ecol. 2009 Feb;35(2):219-29. doi: 10.1007/s10886-008-9586-0. Epub 2009 Jan 24.
Western flower thrips (Frankliniella occidentalis) has become a key insect pest of agricultural and horticultural crops worldwide. Little is known about host plant resistance to thrips. In this study, we investigated thrips resistance in F (2) hybrids of Senecio jacobaea and Senecio aquaticus. We identified thrips-resistant hybrids applying three different bioassays. Subsequently, we compared the metabolomic profiles of these hybrids applying nuclear magnetic resonance spectroscopy (NMR). The new developments of NMR facilitate a wide range coverage of the metabolome. This makes NMR especially suitable if there is no a priori knowledge of the compounds related to herbivore resistance and allows a holistic approach analyzing different chemical compounds simultaneously. We show that the metabolomes of thrips-resistant and -susceptible hybrids differed considerably. Thrips-resistant hybrids contained higher amounts of the pyrrolizidine alkaloids (PA), jacobine, and jaconine, especially in younger leaves. Also, a flavanoid, kaempferol glucoside, accumulated in the resistant plants. Both PAs and kaempferol are known for their inhibitory effect on herbivores. In resistant and susceptible F (2) hybrids, young leaves showed less thrips damage than old leaves. Consistent with the optimal plant defense theory, young leaves contained increased levels of primary metabolites such as sucrose, raffinose, and stachyose, but also accumulated jacaranone as a secondary plant defense compound. Our results prove NMR as a promising tool to identify different metabolites involved in herbivore resistance. It constitutes a significant advance in the study of plant-insect relationships, providing key information on the implementation of herbivore resistance breeding strategies in plants.
西花蓟马（Frankliniella occidentalis）已成为全球农业和园艺作物的主要害虫。关于寄主植物对蓟马的抗性知之甚少。在本研究中，我们调查了千里光（Senecio jacobaea）和水飞蓟（Senecio aquaticus）的F（2）杂交种对蓟马的抗性。我们通过三种不同的生物测定法鉴定出抗蓟马的杂交种。随后，我们应用核磁共振光谱（NMR）比较了这些杂交种的代谢组学图谱。NMR的新进展有助于广泛覆盖代谢组。如果对与食草动物抗性相关的化合物没有先验知识，这使得NMR特别适用，并允许采用整体方法同时分析不同的化合物。我们表明，抗蓟马和感蓟马杂交种的代谢组有很大差异。抗蓟马杂交种含有较高含量的吡咯里西啶生物碱（PA）、雅各宾碱和夹可尼宁，尤其是在较嫩的叶片中。此外，一种类黄酮山奈酚糖苷在抗性植物中积累。PA和山奈酚都以其对食草动物的抑制作用而闻名。在抗性和感病的F（2）杂交种中，嫩叶比老叶受到的蓟马损害更少。与最佳植物防御理论一致，嫩叶中初级代谢产物如蔗糖、棉子糖和水苏糖的含量增加，同时还积累了作为植物次生防御化合物的雅各酮。我们的结果证明NMR是鉴定参与食草动物抗性不同代谢物的有前途的工具。它在植物与昆虫关系的研究中取得了重大进展，为植物中食草动物抗性育种策略的实施提供了关键信息。
