Dutch #botanist who was one of the first #microbiologists to recognize the importance of #lactic…

Dutch #botanist who was one of the first #microbiologists to recognize the importance of #lactic #acid #bacteria for #food production. He contributed to #agriculture, #botany, #microbiology, #chemistry and #genetics. In research on #gall #wasps and the formation of galls (1882) he laid groundwork for the theory of ontogeny in higher #plants and #animals whereby growth #enzymes act in series in a fixed order (1917). Since his father was a tobacco dealer who went bankrupt, he researched the tobacco mosaic virus, which causes a disease of tobacco plants with serious economic impact. He discovered that even after filtering the sap of an infected plant to remove bacteria, the liquid was still able to carry infection to another plant. Thus he knew the disease was not due to bacteria, but by something else in the the liquid, which he called a filterable #virus (from Latin word for poison) but which later researchers demonstrated in fact had a particle form.