Institute for Ecological Chemistry, Plant Analysis and Stored Product Protection, Federal Research Centre for Cultivated Plants, Julius Kühn-Institute, Berlin, Germany.
Applied Zoology/Animal Ecology, Dahlem Centre of Plant Sciences, Freie Universität Berlin, Berlin, Germany.
Plant Cell Environ. 2021 Feb;44(2):519-534. doi: 10.1111/pce.13949. Epub 2020 Nov 24.
Divergence of chemical plant defence mechanisms within the Brassicaceae can be utilized to identify means against specialized pest insects. Using a bioassay-driven approach, we (a) screened 24 different Brassica napus cultivars, B. napus resyntheses and related brassicaceous species for natural plant resistance against feeding adults of the pollen beetle (Brassicogethes aeneus), (b) tested for gender-specific feeding resistance, (c) analysed the flower bud metabolomes by a non-targeted approach and (d) tested single candidate compounds for their antifeedant activity. (a) In no-choice assays, beetles were allowed to feed on intact plants. Reduced feeding activity was mainly observed on Sinapis alba and Barbarea vulgaris but not on B. napus cultivars. (b) Males fed less and discriminated more in feeding than females. (c) Correlation of the metabolite abundances with the beetles' feeding activity revealed several glucosinolates, phenylpropanoids, flavonoids and saponins as potential antifeedants. (d) These were tested in dual-bud-choice assays developed for medium-throughput compound screening. Application of standard compounds on single oilseed rape flower buds revealed highly deterrent effects of glucobarbarin, oleanolic acid and hederagenin. These results help to understand chemical plant defence in the Brassicaceae and are of key importance for further breeding strategies for insect-resistant oilseed rape cultivars.
在十字花科植物中，化学防御机制的差异可以被利用来识别针对专门害虫的防治方法。我们采用生物测定驱动的方法：（a）筛选了 24 种不同的油菜品种、油菜合成品和相关的芸薹属物种，以研究其对花粉甲虫（Brassicogethes aeneus）成虫的天然植物抗性；（b）测试了性别特异性的取食抗性；（c）通过非靶向方法分析花蕾代谢组；（d）测试了单一候选化合物的抗食活性。（a）在非选择试验中，让甲虫在完整的植物上取食。在白花芥蓝和普通葶苈中，甲虫的取食活性明显降低，但油菜品种则不然。（b）雄性的取食量和取食选择性均低于雌性。（c）代谢物丰度与甲虫取食活性的相关性表明，几种硫代葡萄糖苷、苯丙素、类黄酮和皂苷可能是潜在的抗食剂。（d）这些化合物在为中高通量化合物筛选开发的双花蕾选择试验中进行了测试。将标准化合物应用于单个油菜花蕾上，发现了葡萄糖苷、齐墩果酸和栀子苷具有高度的驱避作用。这些结果有助于理解十字花科植物的化学防御机制，对进一步培育抗虫油菜品种的策略具有重要意义。
