Plasticity of host finding behaviour of herbivorous insects in dependence of environmental factors

欧洲的大多数植食性昆虫都是食草动物专家。它们必须找到适合取食和产卵的特定寄主植物。从远处看，使用挥发性和视觉线索，而接触后，化学触觉线索也在宿主发现和接受行为中发挥作用。不同的植物物种都有其特有的化学代谢物谱，即使在一个物种内，由于年龄的不同，其组成也可能有很大的差异。此外，紫外线辐射和氮素有效性等环境因素会导致植物代谢物的质量和数量以及植物的外观发生变化。因此，食草性昆虫必须具有明显的行为可塑性，才能对这种变化做出反应，并能够识别合适的宿主。此外，它可能更喜欢能提高它的适合度的植物。该项目的主要目的是评估少食性芥菜叶甲虫Phaedon cochleariae(鞘翅目：叶甲科)如何检测植物之间在嗅觉、化学触觉和/或视觉线索方面的化学差异，甲虫的寄主寻找行为如何受到环境影响的植物质量变化的影响，以及寄主寻找行为是否会因个体的经验而改变。

Most phytophagous insects within Europe are feeding specialists. They necessarily need to find their specific host plants which are acceptable for feeding and oviposition. From the distance, volatile and visual cues are used, whereas after contact also chemotactile cues play a role in the host finding and acceptance behaviour. Different plant species contain each their characteristic chemical metabolite profile, which can vary highly in its composition even within a species from organ to organ and due to age. Furthermore, environmental factors such as ultraviolet radiation and nitrogen availability can induce changes in the quality and quantity of plant metabolites as well as the visual appearance of the plant. Thus, an herbivorous insect must possess a pronounced behavioural plasticity to respond to such variation and to be able to recognise a suitable host. Also, it might prefer plants that increase its fitness. The main aims of the project are to evaluate, how the oligophagous mustard leaf beetle, Phaedon cochleariae (Coleoptera: Chrysomelidae), can detect chemical differences between plants with regard to olfactory, chemotactile and/or visual cues, how the host finding behaviour of the beetles is affected by environmentally influenced changes of plant quality, and whether the host finding behaviour is modified by the experience of the individual.