Jean Louis Léon Guignard (13 April 1852 in

Mont-sous-Vaudrey Mont-sous-Vaudrey () is a commune in the Jura department in Bourgogne-Franche-Comté in eastern France. Population Personalities Mont-sous-Vaudrey was the birthplace of Jules Grévy (1813-1891), President of the French Third Republic. ...

– 7 March 1928 in Paris) was a French

pharmacist A pharmacist, also known as a chemist (Commonwealth English) or a druggist (North American and, archaically, Commonwealth English), is a healthcare professional who prepares, controls and distributes medicines and provides advice and instructi ...

and

botanist Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek wo ...

. 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 Gaspard Adolphe Chatin (30 November 1813 – 13 January 1901) was a French physician, mycologist and botanist who was born in Isère, and died in Les Essarts-le-Roi. He was the first to prove that goiter was related of iodine deficiencies. He stud ...

as chair of botany at the Ecole Supérieure de Pharmacie in Paris. From 1900 to 1910 he was dean to the faculty of pharmacy.Guignard, Léon
Société d'Histoire de la Pharmacie In 1899 he was named president of the Académie des sciences. He was also a member of the

Société de biologie The Société de biologie is a learned society founded in Paris in 1848. The society was conceived during the French Revolution of 1848. The members of the society held regular meetings and published the proceedings in a new scientific journal. The ...

(from 1888), the

Académie de Médecine An academy ( Attic Greek: Ἀκαδήμεια; Koine Greek Ἀκαδημία) is an institution of secondary or tertiary higher learning (and generally also research or honorary membership). The name traces back to Plato's school of philosophy ...

(from 1897) and the

Académie d'Agriculture The Académie d'agriculture de France is a voluntary association aiming to contribute to the evolution of agriculture and rural life in the scientific, technical, economic, judicial, legal, social and cultural fields. It is the successor to the s ...

(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 Louis may refer to: * Louis (coin) * Louis (given name), origin and several individuals with this name * Louis (surname) * Louis (singer), Serbian singer * HMS ''Louis'', two ships of the Royal Navy See also Derived or associated terms * Lewis ( ...

published ''

Guignardia ''Guignardia'' is a genus of fungi in the family Botryosphaeriaceae. The genus name of ''Guignardia'' is in honour of Jean Louis Léon Guignard (1852–1928), who was a French pharmacist and botanist. The genus was circumscription (taxonomy), c ...

',which is a genus of fungi in the family Botryosphaeriaceae and named in Guignard's honour.

Selected works

* ''Recherches anatomiques et physiologiques sur l'embryogénie des légumineuses'', 1881 – Anatomical and physiological research on the embryology of legumes. * ''Recherches sur le sac embryonnaire des phanérogames angiospermes'', 1882 – Research on the embryonic sac of

angiosperm Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (), commonly called angiosperms. The term "angiosperm" is derived from the Greek words ('container, vessel') and ('seed'), and refers to those plants th ...

s. * ''Sur la division du noyau cellulaire chez les végétaux'', 1883 – On the

cell nucleus The cell nucleus (pl. nuclei; from Latin or , meaning ''kernel'' or ''seed'') is a membrane-bound organelle found in eukaryotic cells. Eukaryotic cells usually have a single nucleus, but a few cell types, such as mammalian red blood cells, h ...

division in plants. * ''Nouvelles observations sur la structure et la division du noyau cellulaire'', 1884 – New observations on the structure and the division of the cell nucleus. * ''Sur les organes reproducteurs des hybrides végétaux'', 1886 – On the reproductive organs of plant hybrids. * ''Sur les effets de la pollinisation chez les orchidées'', 1886 – The effects of pollination in orchids. * ''Observations sur l'appareil mucifère des Laminariacées'', 1892 – On the muciferous apparatus in Laminariaceae. * ''Recherches sur le développement de la graine et en particulier du tégument séminal'', 1893 – Research on the development of seeds, in particular the seed coat. * ''L'origine des sphères directrices'', 1894 – The origin of director spheres. * ''Les découvertes récentes sur la fécondation chez les végétaux angiospermes'', 1899 – Recent discoveries on fertilization in angiosperms. * ''Sur les anthérozoides et la double copulation sexuelle chez les végétaux angiospermes'', 1899 – On

antherozoid An antheridium is a haploid structure or organ producing and containing male gametes (called ''antherozoids'' or sperm). The plural form is antheridia, and a structure containing one or more antheridia is called an androecium. Androecium is also ...

s and double copulation in angiosperms. * ''La double fécondation chez les renonculacées'', 1901 – Double fertilization in buttercups. * ''Sur la double fécondation chez les solanées et les gentiancées'', 1901 – Double fertilization in

Solanaceae The Solanaceae , or nightshades, are a family of flowering plants that ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of agricultural crops, medicinal plants, spices, weeds, and orn ...

and Gentianaceae. * ''Le haricot a acide cyanhydrique (Phaseolus lunatus)'', 1906 – A bean containing hydrocyanic acid ('' Phaseolus lunatus''). * ''L'ovule chez les Apocynacées et Asclépiadacées'', 1910 – The ovule in Apocynaceae and Asclepiadoideae.HathiTrust Digital Library
published works

References

{{DEFAULTSORT:Guignard, Leon 1852 births 1928 deaths People from Jura (department) Academic staff of the University of Lyon 19th-century French botanists French pharmacists Plant physiologists 20th-century French botanists