Morphological Characterization and Relationships of Wild Tomatoes (solanum L. Sect. Lycopersicon)

Wild tomatoes (Solanum L. sect. Lycopersicon (Mill.) Wettst.) are native to western South America. Different classifications have been based on morphological or biological species concepts. Molecular data from mitochondrial DNA restriction sites, nuclear and chloroplast DNA restriction length fragment polymorphisms, and most recently gene sequences of the single-copy nuclear GBSSI or waxy gene, also have been used to examine species relationships. This study is a companion to the GBSSI gene sequence study of the same accessions. It provides the first explicit use of morphological data to examine distinctness and relationships of all 10 wild tomato species (including the newly described S. galapagense), with a concentration on accessions of the most widespread and variable species, S. peruvianum. Phenetic and cladistic analyses largely support the nine species outlined by the latest treatment by C. Rick, but demonstrate the distinct nature of the northern and southern Peruvian populations of S. peruvianum, and suggest that they may represent distinct species.