Inaugural talk of our new professors

We’re thrilled to invite you to the inaugural lecture of Professors Jean-Claude Caissard and Patrick Grof-Tisza!

🗓️ Date: June 12 2026
🕒 Time: 14:00 to 16:45
📍 Location: Faculté des Sciences et Techniques, Amphitheater J108, 23 rue du Docteur Paul Michelon, 42000 Saint-Etienne
🥂 Reception: from 16:45

 

🌹Jean-Claude Caissard will address the following question: Why do plants have a smell?

Aromatic and fragrant plants are distinguished by their ability to produce a wide variety of volatile compounds. These specialised metabolites fulfil major ecological functions, particularly in interactions with other living organisms. They contribute to chemical communication by playing a role in attracting pollinators, repelling herbivores or pests, recruiting parasitoids, or in signal exchange between plants.

The biosynthesis of these compounds relies on complex metabolic pathways. Some are widely conserved within the plant kingdom, whilst others exhibit a high degree of specialisation, or even a biochemical uniqueness specific to a given species. This biosynthetic diversity reflects the adaptive evolution of plants to specific ecological niches.

Furthermore, aromatic plants display a remarkable variety of anatomical structures involved in the secretion and storage of essential oils.

These structures, ranging from glandular hairs to secretory channels, reflect the morphological and functional richness associated with the production of volatile compounds.

Through a selection of examples drawn from my research, I will illustrate these various aspects of the biology and biochemistry of aromatic plants, highlighting the complexity and specificity of their chemical strategies.

 

🐝Patrick Grof-Tisza will present his past and future research regarding Plant Volatiles in Ecological Interactions.

Plants have evolved sophisticated ways to detect and respond to their environment, allowing them to interact with herbivores, the predators of those herbivores (natural enemies), and even neighboring plants. These interactions involve a range of processes, from detecting chemical cues associated with insect attack to producing defensive traits, including volatile organic compounds that move through the air and influence the behavior of surrounding organisms. For example, sagebrush, a highly aromatic shrub that dominates much of the American West, can influence the defensive responses of neighboring plants, with the strength of this effect depending in part on genetic relatedness. In maize–bean–squash polycultures, volatile cues can be shared among crops, enhancing their defenses and reducing herbivore damage.

As the impacts of human activities on natural systems become increasingly apparent, there is a growing need for more sustainable approaches. A more complete understanding of plant volatiles, from their biosynthesis to their ecological function, is essential for both advancing fundamental knowledge and informing practical solutions.