The plant surface - a vast stage for interactions… How do plants create flexible, long-lasting, water-proof skins that grow with their organs? How do plants seal their vast surface against adverse climatic conditions? How do insects assess host suitability when they first land on a plant? How can plants select for mutualistic partner insects while excluding their parasitic competitors? How do pitcher plants catch their prey?
All primary aboveground plant organs, e. g. leaves, stems, flowers and fruits, are covered by waxy extracellular membranes. The surface of this 'cuticle' forms the interface between plants and their environment, and is therefore of special physiological and ecological relevance. The wax constituents of the cuticle, on one hand, restrict water loss to the atmosphere and therefore perform a central physiological role. On the other hand, the cuticle likely acts as a first chemical and mechanical barrier against pathogenic micro-organisms and herbivorous insects. Characteristic cuticular compounds might act as deterrents against generalistic herbivores, while specialized insects could use them as clues for host-plant recognition.
Finally, microscopic structures on the plant surface can reduce the adhesion of insect feet, thereby creating slippery grounds for the animals. Although all these general properties of plant cuticles have been studied for decades, the individual functions of species-specific surfaces remain unclear. To gain a deeper understanding of this important plant tissue, we are integrating molecular biological, chemical, micro-morphological, eco-physiological and biomechanical methods.
My research focuses on: 1) the biosynthesis of selected surface compounds, especially its spatial and temporal regulation, 2) the accumulation of surface compounds in the course of organ development, 3) the structure elucidation of novel surface compounds, applying GC-MS and HPLC, microscale derivatization and synthesis of authentic standards 4) the contribution of individual wax layers to the physiological function as a transport barrier for water and volatiles, 5) the role of characteristic surface compounds in creating slippery surfaces and as infochemicals moderating insect behaviour.