French pharmacist and botanist (1852–1928)
Jean Louis Léon Guignard (13 April 1852 in Mont-sous-Vaudrey – 7 March 1928 in Paris) was a French pharmacist and botanist.
In 1882 he received his doctorate of sciences in Paris, and afterwards served as a professor of botany at the Faculty of Sciences of Lyon. In 1887, he succeeded Gaspard Adolphe Chatin as chair of botany at the Ecole Supérieure de Pharmacie in Paris. From 1900 to 1910 he was dean to the faculty of pharmacy.
In 1899 he was named president of the Académie des sciences. He was also a member of the Société de biologie (from 1888), the Académie de Médecine (from 1897) and the Académie d'Agriculture (from 1915). In 1920 he was chosen a commander in the Legion d'Honneur.
Along with biologist from Kyiv Sergei Navashin, he is credited as the co-discoverer of double fertilization in flowering plants. The two men made their discoveries independent of each other, Navashin in 1898 and Guignard in 1899. He also introduced a new method for detecting the presence of hydrocyanic acid in plants. In addition, he conducted significant research on the origin and structure of integuments for a large number of seeds.
In 1892, botanists Pierre Viala and Louis Etienne Ravaz published "Guignardia',which is a genus of fungi in the family Botryosphaeriaceae and named in Guignard's honour.
Selected works.
 ;templatestyles src="Botanist/styles.css"/ ;The standard author abbreviation Guignard is used to indicate this person as the author when citing a botanical name.
References.
 ;templatestyles src="Reflist/styles.css" / ;