From land plants to marine diatoms: the scientific journey of a plant eco-physiologist

Abstract

During my career, mainly I have studied the interaction between environmental factors and the physiology of plants and algae. To cite only the most important, a plant of agronomic interest: Zea mays, then a halophyte: Halopeplis amplexicaulis (Vahl) Ung, brown macroalgae of the genera Fucus and Cystoseira and finally microalgae as Pavlova lutheri, but mostly diatom as Haslea ostrearia and Odontella aurita that have occupied my last 20 years of research at Le Mans University (France). Most of the time, numerous and varied physiological parameters such as growth, photosynthesis by oximetry and modulated fluorometry, metabolic pathways using 14C, enzymatic activities of the major enzymes of carbon fixation and of the antioxidant enzyme system, poly-insaturated fatty acids composition and metabolism in microalgae have been studied in conditions of stress. Currently approaching retirement, I finally conduct experiments with diatoms rich in polyunsaturated fatty acids, supplied as a food supplement to high-fat fed rats having a metabolic syndrome

Keywords:

• diatom
• macroalga
• microalga
• stress
• photosynthesis
• fatty acid

Acknowledgements

I thank the Editor of Diatom Research and particularly my colleague, Prof. B. Schoefs, for giving me the opportunity to present my scientific activities. This work would not have been possible without the participation of many students that I co-directed during their PhDs and of numerous colleagues. I thank my colleagues who tolerated my humor (not always politically correct) through the years. Special thanks go to Prof. A. Manceau who understood it best, and was my closest colleague for almost 30 years. I also thank my colleagues at Nantes University, especially Prof. J.M. Robert who, more than 20 years ago, gave me the opportunity to study the physiology of his favorite model diatom: Haslea ostrearia. I also thank the managers of the Centre de Resources Biologiques (MMS, Nantes University, France) who have always kindly and quickly provided diatoms needed for these various studies. I especially thank all the technicians of the biology laboratory of the University of Maine (Le Mans), and other laboratories who participated directly or indirectly in my work over the last 30 years: I. Queguiner, C. Vachoux, P. Rosa, P. Gaudin, P. Roussel, B. Jacquette, B. Moreau and S. Hiard. More particularly, I thank E. Pradier who always helped me enthusiastically throughout my career, even when I was far away from the University of Maine.