VILMORIN, PIERRE LOUIS FRANçOIS LEVEQUE DE

(b. Paris, France, 18 April 1816; d. Paris, 21 March 1860), botany.

Valmorin’s father, Philippe André Leveque de Vilmorin, was president of the distinguished Paris seed firm Vilmorin-Andrieux et Cie; and he brought up Louis, his eldest son, to succeed him when he retired (1843). Louis was physically handicapped and appears to have been educated privately; and although he learned the business thoroughly and was capable of heading the company, he always took more interest in research. His wife, Elisa Bailly, helped him in the business and also conducted research on strawberries. Henri, the eldest of their three sons, succeeded to the business.

The firm of Vilmorin-Andrieux had already established a reputation for breeding improved stock; since 1771 it had regularly published catalogs listing available varieties with instructions for their cultivation. Under Louis de Vilmorin the firm extended and organized the work on breeding and set up an experimental farm at Verrières-le-Buisson.

Vilmorin’s first important work was on the breeding of wheat. The Société d’ Agriculture had asked his father to investigate the classification of cultivated wheats; but most of the work was done by Louis, who in 1850 published a classified catalog of seven species and fifty-three distinct varieties of wheat, indicating not only their characters but also their relationships. In it he showed awareness that the horticulturist’s classification was not the same as the botanist’s in dealing with distinct species.

From 1850 until his death Vilmorin published a series of papers on the breeding of cereal grains, potatoes, sugarbeets, and flowers. He was not isolated in the world of commerce, but was a friend of J. B. Boussingault and collaborated with Édouard Duchesne. He also edited the periodical Bon jardiniere from 1844 until hius death.

Vilmorin’s work of greatest economic importance was breeding a new variety of sugarbeet with a straight taproot and a sugar content of around 20 percent, nearly double the previous maximum. In this work, published in 1856, he already showed his appreciation of the importance of finding a reliable method of assaying for the sugar content and of conducting the breeding under controlled conditions. The main part of his paper in 1856 was a record of his assay method, but he outlines his breeding techniques, and discusses his results with the frank admission that he does not understand the transmission of the “qualité sucrée,” . He selected plants with a high percentage of sugar and gathered and sowed the seed separately by a method originated by his father, but he does not record methods of preventing cross-fertilization. He found in the first generation three distinct groups: one of plants that were consistent high yielders, one with variable yield but including those of exceptionally high yield, and another of consistent low yielders. He then showed that the consistently high-yielding group bred true, forming a race that was high in sugar in the second generation and even more in the third. These variations were independent of culture and he believed that his rich race was permanently fixed, though of course yield would then be affected by culture.

Vilmorin’s most significant work in breeding was reported by his son Henri in 1877. From 1856 to 1860 he bred plants of Lupinus hirsutus with pink or blue flowers, counted the progeny of each color, and tabulated the results. This was the first experimental work since Sageret to show numerical relations of the segregation of characters and was contemporary with Mendel’s experiments. The lupines were generally self-fertilized, commonly blue but sometimes pink, and had no intermediate colors. From twenty-seven blue-flowered plants he obtained twenty-five blue that bred true and two pink that in later generations produced plants in ratios approximating three pink to one blue. Since Vilmorin’s numbers were small, however, and since it seems likely that some cross-fertilization occurred, he concluded that there was no mathematical relationship and the segregation was due to conflict of vital forces. His theory of centripetal forces (the hereditary influence of parents) and centrifugal ones (the totality of ancestral influence), propounded in 1851, was refined to include the force of individual variation, and he considered that the proportion of pink and blue flowers measured the strength of these forces. The greatest tendency was to resemble parents, and the forces of atavism weakened with distance.

BIBLIOGRAPHY

I. Original Works. Vilmorin’s works include Essai d’un catalogue méthodique et synomique des froments qui composent la collection de L. Vilmorin (Paris, 1850); “Note sur la création d’une nouvelle race de betteraves à sucre. Considérations sur l’hèrèditè dans les végétaux,” in Comptes rendus…de l’Acadèmie des sciences, 43 (1856), 871–874; Notices sur l’amèlioration des plantes par le semis et considèrations sur l’hèrèditè dans les végétaux (Paris, 1869); “Note sur une expérience relative à l’ètude de l’hèrèditè dans les végétaux.” in Mémories de la Société nationale d’agriculture de France for 1877 (1879), 233–231, written by his son Henri; and “Tableau des effets de la rouille sur une série de variétés de froments,” ibid., 126 (1881), 219–226.

II. Secondary Literature. There is a short unsigned obituary in Gardener’s Chronicle (1860), 366; and an appreciative notice by J. A. Barral in Revue horticole (1860), 172–174; there is also a memorial in Genetics. 19 (1934), comprising a frontispiece protrait, 3 unnumbered pp. of explanatory text by John H. Parker, and text on the back cover; the note refers to, but does not locate, a bibliography of the publications of the Vilmorins by J. H. Parker, in typescript. Most information and comment on Vilmorin’s work is found in surveys of the family. The most critical scientific assessment is in H. F. Roberts, Plant Hybridization Before Mendel (New York -London, (1965), 143–151. Also see Gustave Heuzé “Les Vilmorin,” in Revue horticole, 71 (1899), 453–459; and “La maison Vilmorin-Andrieux et Cie,” in Revue de l’horticulture belge et étrangère, 36 (1910), 249–257.

There is a general history of sugarbeet genetics by J. L. de Vilmorin, L’hérédité chez la betterave cultivée (Paris, 1923), pp. 69–73 of which relate to the work of Louis de Vilmorin.

Diana M. Simpkins