Pierre-Marie-Alexis Millardet
Pierre-Marie-Alexis Millardet (13.12.1838 – 15.12.1902) was an eminent French botanist, mycologist, and ampelographer, and a Professor of Botany at the University of Bordeaux. His fundamental research played a decisive role in rescuing European viticulture from the ecological and economic catastrophe caused by the invasion of North American pests and diseases in the second half of the 19th century.
Scientific Activity and the Fight Against Phylloxera
Alexis Millardet studied at the universities of Heidelberg and Freiburg, later holding professorial chairs in Strasbourg and Nancy, before being appointed Chair of Botany at the University of Bordeaux in 1876. From 1874, he was actively involved in the work of the Commission for the Control of Phylloxera (Phylloxera vastatrix).
Millardet was among the first scientists to establish the physiological reasons behind the resistance of American Vitis species to the root form of phylloxera. Together with Jules Émile Planchon, he developed and scientifically justified the method of reconstructing European vineyards by grafting indigenous Vitis vinifera varieties onto phylloxera-resistant American rootstocks, which laid the foundation for modern intensive viticulture.
Contribution to Rootstock Breeding
Recognizing that pure American species (Vitis riparia, Vitis rupestris, Vitis berlandieri) were not always adapted to specific European soil conditions, particularly calcareous soils, Millardet, in collaboration with Charles de Grasset, launched a large-scale breeding program based on hybridization. Their long-term partnership resulted in the creation of a series of rootstocks widely known under the breeders' acronym "Millardet et de Grasset" (Mgt / MGt):
- 41 B Millardet et de Grasset (Chasselas × Vitis berlandieri) — a historical rootstock that demonstrated exceptional tolerance to active lime in the soil, becoming indispensable for the Champagne and Cognac regions.
- 420 A Millardet et de Grasset (Vitis berlandieri × Vitis riparia) — a rootstock with a deep root system, moderate vigor, and excellent resistance to lime-induced chlorosis.
- 101-14 Millardet et de Grasset (Vitis riparia × Vitis rupestris) — a widely used rootstock for damp, clayey soils, promoting early ripening of the scion.
Invention of the Bordeaux Mixture
In addition to rootstock breeding, Millardet secured his place in history as the creator of the first effective chemical plant protection product. In 1882, while researching the downy mildew (Plasmopara viticola) problem introduced from the USA, he noticed that vines in Médoc treated with a mixture of copper sulfate and lime to deter pilferage remained unaffected by the disease. In 1885, following a series of experiments, the scientist published the exact formula for the fungicide, which gained worldwide recognition as the "Bordeaux mixture" (Bouillie bordelaise).