Solanumis one of the world's largest and economically most important plant genera, including 1245 currently accepted species and several major and minor crops (e.g., tomato, potato, brinjal eggplant, scarlet eggplant, Gboma eggplant, lulo, and pepino). Here we provide an overview of the evolution of 25 key morphological traits for the major and minor clades of this giant genus based on stochastic mapping using a well‐sampled recently published phylogeny ofSolanum. The most evolutionarily labile traits (showing >100 transitions across the genus) relate to plant structure (growth form and sympodial unit structure), herbivore defence (glandular trichomes), pollination (corolla shape and colour), and dispersal (fruit colour). Ten further traits show evolutionary lability with 50–100 transitions across the genus (e.g., specialised underground organs, trichome structure, leaf type, inflorescence position and branching, stamen heteromorphism). Our results reveal a number of highly convergent traits inSolanum, including tubers, rhizomes, simple leaves, yellow corollas, heteromorphic anthers, dioecy, and dry fruits, and some unexpected pathways of trait evolution that could be explored in future studies. We show that informally named clades ofSolanumcan be morphologically defined by trait combinations providing a tool for identification and enabling predictive phylogenetic placement of unsampled species.

Conservation and sustainable use of species diversity require a description of the environment where they develop. The objectives were to determine ecological descriptors and climatic diversity of areas along the distribution range of 12 species of wild tomatoes (Solanum sect. Lycopersicon) and four wild species of phylogenetically related groups (Solanum sect. Juglandifolia and sect. Lycopersicoides), as well as their ecological similarity in Latin America. With 4228 selected tomato accessions and an environmental information system (EIS) composed of 21 climatic variables, diversity patterns of the distribution areas were identified for each species, as well as ecological descriptors through the use of geographic information systems (GIS). The contribution of climatic variables to the species geographical distribution was identified by principal component analysis (PCA), and similarity in species distribution as a function of the variables identified with cluster analysis (CA). Climatic characteristics and the environmental amplitude of wild tomatoes and related species along their distributional range were satisfactorily determined by ecological descriptors. Eleven climate types were identified, predominantly BSk (arid, steppe, cold), BWh (arid, desert, hot), and Cfb (temperate, no dry season, warm summer). PCA determined 10 most important variables were the most important for the geographical distribution. Six groups of species were identified according to CA and climatic distribution similarity. This approach has shown promissory applications for biodiversity conservation of valuable genetic resources for tomato crop breeding.

Tomato (Solanum lycopersicum L.) is a vegetable with worldwide importance. Its wild or close related species are reservoirs of genes with potential use for the generation of varieties tolerant or resistant to specific biotic and abiotic factors. The objective was to determine the geographic distribution, ecological descriptors, and patterns of diversity and adaptation of 1296 accessions of native tomato from Mexico. An environmental information system was created with 21 climatic variables with a 1 km² spatial resolution. Using multivariate techniques (Principal Component Analysis, PCA; Cluster Analysis, CA) and Geographic Information Systems (GIS), the most relevant variables for accession distribution were identified, as well as the groups formed according to the environmental similarity among these. PCA determined that with the first three PCs (Principal Components), it is possible to explain 84.1% of the total variation. The most relevant information corresponded to seasonal variables of temperature and precipitation. CA revealed five statistically significant clusters. Ecological descriptors were determined and described by classifying accessions in Physiographic Provinces. Temperate climates were the most frequent among tomato accessions. Finally, the potential distribution was determined with the Maxent model with 10 replicates by cross-validation, identifying areas with a high probability of tomato presence. These results constitute a reliable source of useful information for planning accession sites collection and identifying accessions that are vulnerable or susceptible to conservation programs.

Background and Aims: Navigating morphological diversity in large plant genera with hundreds of species remains a challenge, making identification in these groups daunting. Traditional text-based identification tools either are lacking or, if published, they are behind paywalls; they can also be difficult to use due to length and technical language and are often heavily reliant on reproductive characters. Methods: In this paper, we present lessons learnt from building accessible multi-access keys to the large and economically important genus Solanum that currently includes 1 239 accepted species. We use a set of characters selected from monographs and expert assessment and the online key generation platform Xper3 to create two multi-access keys for Solanum. Results: The process we used for Solanum involves first identification of the correct infrageneric group, followed by a second key that enables species-level identification. This two-step identification process is faster to produce and enables the publication of keys in a stepwise manner. Breaking down a large genus into more bite-sized chunks by using a small set of vegetative characters is key to success, helping users to confidently narrow down their options. Conclusions: In Solanum most clades and even species are defined by multiple rather than single putative apomorphies, which means multi-access keys are optimal for fast and accurate identification. Traditional dichotomous keys are not ideal for large groups because they become extremely lengthy and difficult with limited material. Multi-access, online keys can be constructed before a taxonomic treatment is complete, allowing for improved character understanding. The identification strategy used for Solanum can be generalized to other large genera to enable easier user access to a significant proportion of plant diversity.

Calibrachoa Cerv., Fabiana Ruiz & Pav., and Petunia Juss. form a clade within tribe Petunieae (Solanaceae). Phylogenetic studies of Petunieae, either as part of a family-wide analysis or focusing on the genera Calibrachoa and Petunia, have either left Fabiana unsampled or included only a single species. These studies have found conflicting relationships among the three genera with all three possible topologies obtained. Petunia patagonica (Speg.) Millán, originally described in the genus Nierembergia Ruiz & Pav., is morphologically distinct within Petunia and geographically disjunct from other members of the genus. For the first time, in this study we include multiple species of Fabiana, Calibrachoa, and Petunia, including P. patagonica. Using three chloroplast DNA regions and the nuclear gene GBSSI, or “waxy,” our results provide strong support for a sister group relationship between Calibrachoa and Fabiana and for the placement of P. patagonica within Fabiana. Since there is already a species Fabiana patagonica Speg., we provide the new name Fabiana australis Alaria nom. nov. to replace Petunia patagonica.