Sixteenth-century tomatoes in Europe: who saw them, what did they look like, and where did they come from?

Soon after the Spanish conquest of the Americas, the first tomatoes were presented as curiosities to the European royals and drew the attention of sixteenth-century Italian naturalists. Despite of their scientific interest in this New World crop, most Renaissance botanists did not specify where these ‘golden apples’ or ‘pomi d’oro’ came from. The debate on the first European tomatoes and their origin is often hindered by erroneous dating, botanical misidentifications and inaccessible historical sources. The discovery of a tomato specimen in the sixteenth-century ‘En Tibi herbarium’ kept at Leiden, the Netherlands led to claims that its DNA would reveal the ‘original’ taste and pest resistance of early tomatoes.MethodsRecent digitization efforts greatly facilitate research on historic botanical sources. Here we provide an overview of the ten remaining sixteenth-century tomato specimens, early descriptions and 13 illustrations. Several were never published before, revealing what these tomatoes looked like, who saw them, and where they came from.ResultsOur survey shows that the earliest tomatoes in Europe came in a much wider variety of colors, shapes and sizes than previously thought, with both simple and fasciated flowers, round and segmented fruits. Pietro Andrea Matthioli gave the first description of a tomato in 1544, and the oldest specimens were collected by Ulisse Aldrovandi and Francesco Petrollini in c. 1551 from plants grown in the Pisa botanical garden by their teacher Luca Ghini. The oldest illustrations were made in Germany in the early 1550s, but the Flemish Rembert Dodoens published the first image in 1553. The names of early tomatoes in contemporary manuscripts suggest both a Mexican and a Peruvian origin. The ‘En Tibi’ specimen was collected by Petrollini around Bologna in 1558 and thus is not the oldest extant tomato. Although only 1.2% of its DNA was readable, recent molecular research shows that the En Tibi tomato was a fully domesticated, but quite heterozygous individual and genetically close to three Mexican and two Peruvian tomato landraces. Molecular research on the other sixteenth-century tomato specimens may reveal other patterns of genetic similarity and geographic origin. Clues on the ‘historic’ taste and pest resistance of the sixteenth-century tomatoes should not be searched in their degraded DNA, but rather in those landraces in Central and South America that are genetically close to them. The indigenous farmers growing these traditional varieties should be supported to conserve these heirloom varieties in-situ.