Solanum section Lycopersicon (Tomatoes) and allied species: Phylogenetic relationships of wild tomatoes

KNAPP S.; SPOONER D. M.; PERALTA I. E.

Wealth of wild species: Genetic, Genomic and Breeding Resources, Vol. 5 Vegetables

Springer Verlag

Lugar: Berlin Heidelberg; Año: 2009;

The tomatoes and their wild relatives (sects. Lycopersicoides, Juglandifolia and Lycopersicon) are clearly monophyletic and sister to the potatoes (set. Petota), with sect. Etuberosum clearly monophyletic and sister to potatoes + tomatoes s.l. Sect. Lycopersicoides (formerly recognized as a subsection of sect. Lycopersicon) is clearly monophyletic and sister to sect. Juglandifolia + sect. Lycopersicon, and sect. Juglandifolia is clearly monophyletic and sister to sect. Lycopersicon. Within sect. Lycopersicon, S. pennellii in most cases appears at the base of the trees as a polytomy with S. habrochaites, or sometimes forms a clade with this species. This relationship was considered unresolved by Peralta et al. (2008), although morphological data suggest that S. pennellii is sister to the rest of the tomatoes s.str. (sect. Lycopersicon); it is the only species in that group lacking the sterile anther appendage, while the presence of this appendageis a morphological synapomorphy of S. habrochaites and the rest of the clade. Solanum pennellii was placed by Peralta et al. (2008) in its own “group”. Relationships within sect. Lycopersicon have been presented by Peralta et al (2008) as informal species groups as shown in Table 2. Such informal group systems of classification have been widely applied to Solanum by Whalen (1984), Bohs (1994, 2005), Knapp (1991, 2000, 2002), and Spooner et al. (2004). They are not intended to represent formal classification and are provisional names representing most highly supported ideas of relationships that are still unresolved. Solanum huaylasense (a “northern” segregate of S. peruvianum s.l.) is grouped with S. chilense, S. habrochaites, S. corneliomulleri (a segregate of “southern” S. peruvianum s.l.), and S. peruvianum s.str. in the “Eriopersicon” species group (see Peralta et al. 2008). The self-compatible green-fruited species S. chmielewskii and S. neorickii are related to S. arcanum (another northern segregate of S. peruvianum s.l.) as supported in almost all datasets and are recognized by Peralta et al. (2008) as the “Arcanum” species group. The four species with brightly-colored fruits (S. cheesmaniae, S. galapagense, S. lycopersicum, S. pimpinellifolium) unambiguously form a closely related monophyletic group and are the closest relatives of the cultivated crop. These species with red to orange fruits could be recognized as a formal taxonomic group (as a series for example), but this formal classification has not been taken up at present because of ambiguity in the other species groups in sect. Lycopersicon.