Submitted to: Kurtziana Argentina
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/20/1999
Publication Date: N/A
Citation: Interpretive Summary: This is a review article about the current state of wild tomato taxonomy that will be published with papers by other authors on other genera in this family. The paper explains the variable appearance of the nine species of tomatoes and how these features are used to define tomato species. The paper also reviews the history of describing tomato species, explaining how the early botanist Linnaeus, in 1753, classified tomatoes in the genus Solanum, and then how other botanists classified tomatoes in the genus Lycopersicon, and how we are now changing back to the genus name Solanum. The paper then describes how different tomato classifications are based on either the form of the plant or more recently on how tomato species can interbreed with each other, and how these different criteria affect the taxonomy. The paper ends by summarizing new investigations of tomato species based on DNA or molecular data, and how these results compare to the classifications based on form or on crossability. This paper is part of a series of review papers on the taxonomy of the tomato family and is useful to taxonomists interested in revising the generic boundaries of this family.
Technical Abstract: This is a review article about the current state of wild tomato taxonomy that will be published with papers by other authors on other genera in this family. Wild tomatoes are native to western South America. These species show great morphological variation in leaf, inflorescence, flower, fruit, and seed characters that are taxonomically useful. The generic relationships of wild tomatoes within the Solanaceae have been controversial since the eighteen century. Linnaeus in 1753 placed tomatoes in Solanum while Miller, a contemporary of Linnaeus, classified them in a new genus Lycopersicon. The majority of botanists have subsequently followed Miller. Different numbers of species and conflicting infrageneric classifications have been recognized based on morphology or intercrossability. Two major crossability groups have been identified, one that includes mainly self-compatible species, that can be easily crossed with the cultivated tomato, and a second comprises self-incompatible species that can not be easily crossed with this species. Forty races have been identified in the most widespread and polymorphic species, Solanum peruvianum, with the northern races somewhat reproductively isolated from the southern races. Molecular investigations have analyzed genetic differences and phylogenetic relationships among wild tomatoes. Those using appropriate outgroups have shown that tomatoes and potatoes are closely related. This paper is part of a series of review papers on the taxonomy of the tomato family and is useful to taxonomists interested in revising the generic boundaries of this family.