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The Lysenko Controversy

Many Students have heard of Lysenko and the controversy in the science of genetics but few of them are aware of the scientific facts and theories behind Lysenko's claims. The reason for this is, that the average person only hears the topic mentioned in connection with political propaganda. The following account may therefore be of interest to the serious student who wishes for a greater insight into the problem but lacks the literature.

Trofim Denisovich Lysenko was born in 1898 of peasant parents. The extent of his training is not mentioned in any of the articles I have discovered but most state that he is a plant physiologist by training although Eric Ashby (Scientist in Russia; Penguin) says he was trained as a plant breeder. I have found no mention of any academic qualifications such as are required for scientific person but, considering his position today, it would be very unlikely that he did not hold some form of degree.

Lysenko attributes the phenomen of heredity to the metabolic processes of plants or animals, that is, all organisms assume their particular characteristics as a direct reaction to the nutriment they absorb and, since the food supply, particularly in the case of plants, is intimately associated with the general environment, the heredity of any particular organism must be effected if the environment is altered.

Lysenko therefore claims that if a plant or animal is removed to a new place with a different environment to that from which it came, the metabolism of that organism will be effected to the extent that succeeding generations will inherit those changes effected within the parent plant. This then is what is meant by the term "inheritance of acquired characteristics."

But no theory can be acceptable unless some form of proof is offered. Lysenko cites several examples 'from his own work, that of I. V. Michurin and others to substantiate his theory. Much of it rests on data gained as a result of vegetative hybridisation, i.e.. the grafting of a branch of one individual on to another individual. The 'former, the grafted branch is known as the scion while the host plant is known as the stock. All nutriment in the form of water and inorganic salts which the scion requires for its existence must be absorbed from the sap stream of the stock, which consequently involves an intermingling of the two vascular systems. Now if the material of heredity were carried in the "respiration stream" of a plant it would be expected that hereditary materials in-the stock would be transmitted to the scion and any offspring obtained from the scion would therefore show relationship to the stock. This, Lysenko asserts, is what happens. To prove his case he cites an experiment based on these ideas. Two tomato varieties were used, one with round yellow fruit which was the scion and the other with red pear-shaped fruit which was the stock. Lysenko claims that the hereditary material is carried into the seed of the scion which, when grown produce plants giving a variety of fruit characteristics, in addition to the usual round yellow fruit, such as "red fruit, pink fruit, mottled, fruit, fruit with a 'beak' at the tip and so on." Eric Ashby, a prominent Australian professor of botany (now in England) spent some time in Russia at the conclusion of the war and was able to examine some of Lysenko's work at first hand. I quote here his observations on the above experiment which he published in his book "Scientist in Russia" (Pelican Books).

"One would expect, therefore, Lysenko's claim to be supported by exhaustive and convincing experiments, carried out with pedigree plants free from disease. In actual fact the experiments were carried out with plants of no certain pedigree, some of which carried the virus disease spotted wilt, which produces a red-yellow mottling of the fruit. Furthermore, the numbers of plants used were far too small to establish any such striking claim."