title: The dawn of photosynthesis.
abstract: Photosynthesis may be hold the most important process of plant nutrition, whose essential principles, viz. water, earth, and air, were stated by E. Mariotte and S. Hales between the second half of the seventeenth and the first half of the eighteenth centuries. Subsequently, the pneumatic chemistry demonstrated that the atmospheric air was composed of different kinds of gases. In this context, J. Priestley discovered, in 1772, that the unbreathable air containing high amount of "fixed air" (carbon dioxide) could be made breathable by plants. This English chemist perhaps sensed the importance of this discovery as for the physiology of plant, whilst such importance was clearly perceived by the Dutch physician Jan Ingenhouse. He collected, between 1779 and 1796, a series of experimental results into a reliable hypothesis whose protagonists were air, water and light. Ingenhousz's work was substantiated by the results of the Swiss physiologists Jean Senebier and, in particular, by those of Théodore de Saussure. This latter, in 1804, transformed the hypothesis into a true theory that defined the elaboration of carbon dioxide as nutritional process, and the release of oxygen as a by-product. This theory constituted the ground of photosynthesis for the two successive centuries, distinguished by exciting and splendid research which transformed photosynthesis research into a classic work of scientific genius.
authors.forename: Sergio
authors.initials: S
authors.lastname: Pennazio
mesh_terms: D001901:Botany / Q000266:history*; D049671:History, 18th Century; D049672:History, 19th Century; D010788:Photosynthesis; D018521:Plant Physiological Phenomena