Vavilov, N. I

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Vavilov, N. I.

Russian Geneticist 1887-1943

Nikolay Ivanovich Vavilov was a geneticist and phytogeographer in Russia. He is best known for his attempts to apply the new science of genetics to improve agriculture in Russia, for his novel theory to determine the centers of origin of cultivated plants, and for his tireless efforts to organize science in Russia. Vavilov is also known as one of the outstanding victims of Soviet oppression during the regime of Josef Stalin. He openly opposed the teachings of the antigeneticist Trofim Lysenko. As a result Vavilov was unjustly imprisoned for supporting the very same work in genetics that had made him famous.

Early Life and Career

Vavilov was born in Moscow on November 25, 1887. He was the oldest of four children born to a wealthy Moscow merchant family. His younger brother, Sergey, shared some of his scientific interests and became a well-known physicist and president of the Soviet Academy of Sciences.

From an early age, Vavilov had an interest in applied botany and agriculture. In 1906 he graduated from a commercial high school and entered the Moscow Agricultural Institute. Following graduation in 1911, Vavilov remained with the head of the department of special agriculture to prepare for an academic career. In 1912 he moved to St. Petersburg, where he worked at the Bureau of Applied Botany of the Ministry of Agriculture and at the Bureau of Mycology and Phytopathology. The pivotal moment in his early career came when he was sent to study genetics in England. He left for England in 1913 to study with the eminent geneticist William Bateson. He also worked with the geneticist R. C. Punnett and cereal breeder R. D. Biffen. He returned to Russia just after the outbreak of World War I to complete the thesis for his master's degree titled "Plant Immunity to Infectious Diseases." In 1917 he became professor of agriculture, botany, and genetics at the University of Saratov.

Vavilov rose to prominence shortly following the Russian Revolution. He drew the favorable attention of Lenin and was placed in charge of the Bureau of Applied Botany in St. Petersburg. Under his direction, it became one of the world's most active research institutions. By 1934 it had a staff of approximately twenty thousand persons and was known as Lenin's All-Union Academy of Agricultural Sciences. His success was recognized both at home and abroad. Though he was never a Communist, he was made a member of the Soviet Central Executive Committee. He occupied many important international positions including being named President of the International Congress of Genetics in 1939.

Vavilov's Scientific Work

Vavilov's actual contributions to science were unusual. He did not make any new discoveries or formulate new scientific principles but was instead actively concerned with the application of the new genetics to problems of systematics and agriculture. His work fell into three distinct areas, which had in common a concern with cultivated plants.

His earliest work was concerned with the manner in which plants developed immunity to disease. He developed the concept of degree of specialization. This was based on his observation that the wider the range of hosts of a parasitic fungus, the less likely it is that there will be resistant varieties in any of the host species. In other words, the more hosts that were available, the less likely resistance could develop in any one species. In understanding the mechanism by which this happens, Vavilov sought out new varieties of wheat to test for disease resistance. In the process he discovered an important new disease-resistant wheat species, Triticum timopheevi, which is still used in breeding for disease resistant stocks. The techniques that Vavilov developed for testing disease-resistance are still important tools for plant disease specialists, or plant pathologists.

His second area of research led to the formulation of the law of homologous series in variation. This law held that genetic and morphological regularities existed in the differentiation of species, genera , and families. Such parallel variations, he argued, could be found in all categories of classification. Vavilov recognized that the study of similarities in related species and genera could lead to a valuable analytical tool because it could determine if and where any gaps in series of forms existed. Once this was determined, it was then possible to search for the organism that would fit into such a gap. Vavilov closely studied the parallel variation in many forms, especially the cereals, and in the process amassed an enormous amount of data on this economically important group. He was also able to locate many "missing" forms that were expected if his law held true.

Vavilov was best known for his third area of research into the origin and distribution of cultivated plants. He built on the earlier work of the French geographer Augustin de Candolle, which had used a novel combination of archaeological, historical, linguistic, and botanical evidence to trace the location of origin of cultivated plants. Vavilov additionally applied the insights and methods from two new sciences, cytology and genetics, and traveled extensively to examine and collect close relatives of important cultivated plants. From this work, he derived his own theory of the origin of cultivated plants, which postulated that there were eight principal "centers of origin." According to Vavilov these regions had a broad range of environmental conditions that gave rise to diverse natural floras. Cultivated plants in these regions also had many diverse varieties. Vavilov's novel insight here was to determine that cultivated plants in his centers of origin showed a marked increase in the frequencies of dominant genes compared to plants outside these centers. This, in fact, became his principal criterion for fixing centers of origin. In contrast, cultivated plants outside the centers of origin tended to have much less genetic variability.

Vavilov's centers of origin was a provocative and influential theory for its day. Although the specifics of the theory and the actual centers of origin have been called into question, it opened the way for subsequent research. In the process much was understood about the genetics of cultivated plants and many new varieties were collected and introduced.

Much of Vavilov's research over his life was based on close study of geographic distribution and variation. He traveled widely all over the world, but especially in Asia both to examine and collect usually wild relatives of cultivated plants. His expeditions were organized on a grand scale and led to the collection of an enormous range and number of plant specimens . Many of his collections of cultivated plants were without counterpart and still remain unsurpassed in quality and number. For his research into the origin of wheat alone, he amassed over twenty-five thousand specimens of different varieties of wheat and its wild relatives. With good reason, Vavilov had been called the most widely traveled biologist of his day.

Vavilov and Stalinist Science

Vavilov rose to such prominence that he was the most visible promoter of science in the Soviet Union. He was an advocate of international collaboration and sought to bring the methods and insights of the new science of genetics from Britain and the United States to improve agriculture in the new Soviet system. Unfortunately, this made him an easy target of anti-Western ideology that gained strength under Stalin's regime. Vavilov's support of Western science generally, and genetics in particular, were openly challenged by Trofim Lysenko, one of the most destructive influences in Soviet science. Although he had no training in the field, Lysenko pretended to be an authority in agricultural genetics. He was opposed to Mendelian genetics and Darwinism but instead was an advocate on Lamarckian inheritance , which was more compatible with Soviet ideology. Beginning in the late 1920s, Lysenko and his supporters began to systematically purge the Soviet Union of geneticists who they viewed as slaves to foreign science, as well as anyone who opposed Soviet ideology. Many of the leading geneticists in the Soviet Union were exiled, imprisoned, dispersed, or executed. By the late 1930s Vavilov had been relieved of his administrative duties and was openly targeted by Lysenko.

On August 6, 1940, while he was on a collecting trip in the western Ukraine, Vavilov was arrested by Soviet agents. He was subsequently found guilty of trumped-up charges, including conducting sabotage on Soviet agriculture on behalf of Western powers. He was sentenced to death, but through the efforts of his brother, Sergey, he was instead imprisoned for ten years. He died while in prison on January 16, 1943, as a result of malnutrition.

Vavilov's case was examined closely after Stalin's death. He was subsequently rehabilitated, his scientific work was republished, and his contributions fully noted. He remains one of the most tragic figures in the history of science and his plight serves as a grim lesson against the ideological control of science.

see also Agriculture, History of; Biogeography; Breeding; Candolle, Augustin de; Evolution of Plants, History of; Fabaceae.

Vassiliki Betty Smocovitis