1851-1931

Swiss botanist who discovered a new form of life even smaller than bacteria (now known to be viruses) while studying a contagious disease that affects tobacco plants (the tobacco mosaic virus). He described what remains the most distinctive feature of viruses: to reproduce, a virus must incorporate itself into the living cellular machinery of its host. Beijerinck also made many significant contributions to agriculture through his research in the field of soil microbiology.