Other Free Encyclopedias » Online Encyclopedia » Encyclopedia - Featured Articles » Contributed Topics from U-Z

Vries, Hugo de

plant dutch changes primrose

[duh vrees] (1848–1935) Dutch plant physiologist and geneticist: early investigator of plant genetics.

De Vries, son of a Dutch prime minister of 1872, studied medicine in Holland and Germany and taught botany in both countries, mainly in Amsterdam. As a pupil of at Würzburg he worked on turgor in plant cells, and used the term plasmolysis to describe shrinkage of protoplast from the plant cell wall, with loss of turgidity. He used these studies on water relations in plants both to advance knowledge of plant physiology and to confirm views on osmotic pressure. In the 1880s he became interested in heredity, although he did not then know of work of the 1860s, and he began breeding plants in 1892. He got clear examples of the ‘3:1 ratio’ and then came across Mendel’s work in 1900, and did much to make the work widely known. His breeding experiments included some on the evening primrose, and the striking results led him to propose a bold general ‘theory of mutation’; but we now use the word in a different sense and de Vries’s mutations resulted from changes in chromosome number (to which the evening primrose is prone; its genetic make-up is complex) and not to changes in genes. However, despite being wrongly based, de Vries’s ideas on a rapid alternative to Darwinian evolution led to valuable debate and experimentation, which ultimately did much to establish the Darwinian view.

Vuitton, Louis [next] [back] Von Neumann, John (János)

User Comments

Your email address will be altered so spam harvesting bots can't read it easily.
Hide my email completely instead?

Cancel or