(b. Castelfranc, France, 15 january 1883; d. Paris, Franc, 27 February 1964),
plant physiology, history of science.
Combes was drawn toward biochemistry and plant physiology very early in life. In 1900 he began his studies in pharmacy under P. Vadam; they were completed in 1910 by a doctorate in science, with the remarkable dissertation” “Détermination des intensités lumineuses optima pour les végétaux aux divers stades du développement.” In 1905 Combes had published his first work on the quinones found in living cells.
Combes’s most important teachers at the Sorbonne were Gaston Bonnier, whose daughter he married in 1910, and Marin Molliard, whom he succeeded at that university.
In 1912 Combes was appointed professor of applied botany at the Institut National Aronomique and at the École nationale d’Horticulture. He became chef de travaux in plant physiology at the Sorbonne in 1921, lecturer in 1931, and full professor of plant physiology in 1937. As president of the Société botanique de France (1933) he quided the development of the Fontainebleau laboratory, whose director he later became (1937). In 1943 he founded the laboratory of applied biology of the “Station du Froid” at Bellevue and directed the Office de la Recherche Scientifique Coloniale from 1943 to 1956. It was under his direction that the Adiopodoumé and Bondy research institutes were established.
Comes was a member of the Institut de France, the Academie des Sciences d’ Outre mer, and the Academie d’Agriculture. He was the first president of the Societe Francaise de Physiologie Vegetale.
At the beginning of his career Combes was interested in the metabolism of anthocyanic tissues; then he began a systematic study of the biochemistry of senescent leaves (transformation of sugars, movement of nitrogen compounds). He generalized his observations to the entire plant and provided the first diagram of the nitrogen metabolism of ligneous plants. Next Combes studied the effects of environment on the form and physiology of plants. The original conclusions of his experiments and those of his students under water, plant cells accumulate nitrates, and at high altitudes carbohydrates are stored.
Combes was also interested in the physiology of flowering and showed from the first time the concentration of carbohydrates and nitrogen in young flowers and the massive movement of nitrogen reserves when hay is cut. His work in histochemistry led him to an analysis of lignin and to the study of the localization of cellular heterosides. Mention should be made of an interesting study, L’immunité des végétaux vis-à vis des prinicipes immédiats qu’ils élaborent (1919), the conclusions of which were not properly appreciated until much later.
Throughout his career Combes was also interested in problems of a praactical nature, including the preservation of fruits in a controlled environment and the biochemistry of forcing. He was an excellent micro-biologis; one of his studies in this field was of the dissemination of germs in the atmosphere. From 1917 to 1919 he undertook a series of noteworthy research projects on the typhoid- like afflictions of the horse. Around 1931 Combes became interested in the history and philosophy of science and published Biologie végétale et vitalisme (Paris, 1933) and Histoire de la biologie végétale en France (Paris, 1933).
I. Original Works. Combes’s writings include La vie de la cellule végétale, 3 vols. (Paris, 1933–1946); La forme des vegetaux et le milieu(Paris, 1946); and La physiologie vegetale (Paris, 1948).
II. Secondary Literature. On Combes of his work, see Titres et travaux scientifiques de R. Combes, 3 vols(Paris, 1932–1943); and R. Ulrich, “Raoul Combes,” in Compte rendu hebdomadaire des séances de l’Académie d’agriculture de France (11 Mar. 1964), 430–433.
P. E. Pilet