Edited by Ho Dinh Hai Long An - Vietnam Updated: 25/10/2015
1- Introduction to the Family Solanaceae - Nightshade family
1.1- Overview The Solanaceae, or nightshades, are an economically important family of flowering plants. The family ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs, and trees, and includes a number of important agricultural crops, medicinal plants, spices, weeds, and ornamentals. Many members of the family contain potent alkaloids, and some are highly toxic, but many cultures eat nightshades, in some cases as staple foods. The family belongs to the order Solanales, in the asterid group dicotyledons (Magnoliopsida). The Solanaceae consists of about 98 genera and some 2,700 species, with a great diversity of habitats, morphology and ecology. The family has a worldwide distribution, being present on all continents except Antarctica. The greatest diversity in species is found in South America and Central America. The Solanaceae include a number of commonly collected or cultivated species. The most economically important genus of the family is Solanum, which contains the potato (Solanum tuberosum, in fact, another common name of the family is the "potato family"), the tomato (Solanum lycopersicum), and the eggplant or aubergine (Solanum melongena). Another important genus, Capsicum, produces both chili peppers and bell peppers.
2- Taxonomy of the Family Solanaceae - Nightshade family
2.1- Subfamily Cestroideae (Synonym = Browallioideae) + Overview This subfamily is characterised by the presence of pericyclic fibres, an androecium with four or five stamens, frequently didynamous. The basic chromosome numbers are highly variable, from x=7 to x=13. The subfamily consists of eight genera (divided into three tribes) and about 195 species distributed throughout the Americas. The Cestrum genus is the most important, as it contains 175 of the 195 species in the subfamily. The Cestreae tribe is unusual because it includes taxa with long chromosomes (from 7.21 to 11.511 µm in length), when the rest of the family generally possesses short chromosomes (for example between 1.5 and 3.52 µm in the Nicotianoideae)
+ Tribes and Genera of theSubfamily Cestroideae 1- Tribe Browallieae Hunz. [2 genera, 7 species] + Genera: 1- Genus BrowalliaL., genus with six species distributed throughout the neotropic ecozone to Arizona in the United States 2- Genus StreptosolenMiers, monotypic genus native to the Andes 2- Tribe Cestreae Don. [3 genera, 192 species] This tribe has three genera of woody plants, generally shrubs. + Genera: 1- Genus Cestrum L., some 175 species distributed throughout the neotropic ecozone 2- Genus SesseaRuiz & Pav., 16 species from the Andes 3- Genus VestiaWilld., monotypic genus from Chile 3- Tribe Salpiglossideae (Benth.) Hunz. [2 genera, 6 species] + Genera: 1- Genus Reyesia Gay, four species, distributed throughout Argentina and Chile 2- Genus Salpiglossis Ruiz & Pav., two species originating from southern South America
2.2- Subfamily Goetzeoideae + Overview This subfamily is characterized by the presence of drupes as fruit and seeds with curved embryos and large fleshy cotyledons. The basic chromosome number is x=13. It includes four genera and five species distributed throughout the Greater Antilles. Some authors suggest their molecular data indicate the monotypic genera TsoalaBosser & D'Arcy should be included in this subfamily, endemic to Madagascar, and Metternichia to the southeast of Brazil. Goetzeaceae Airy Shaw is considered as a synonym of this subfamily. + Genera 1- Genus CoeloneurumRadlk., monotypic genus endemic to Hispaniola 2- Genus EspadaeaRchb., monotypic, from Cuba 3- Genus GoetzeaWydler, includes two species from the Antilles 4- Genus HenooniaGriseb., monotypic, originating in Cuba
2.3- Subfamily Nicotianoideae + Overview Subfamily Nicotianoideae has 2 tribes, 8 genera, 107 species. 1- Tribe Anthocercideae G. Don. [7 genera, 31 species] This tribe, endemic to Australia, contains 31 species in seven genera. Molecular phylogenetic studies of the tribe indicate it is the sister of Nicotiana, and the genera Anthocercis, Anthotroche, Grammosolen, and Symonanthus are monophyletic. Some characteristics are also thought to be derived from within the tribe, such as the unilocular stamens with semicircular opercula, bracteolate flowers, and berries as fruit. Genera: 1- Genus AnthocercisLabill., 10 species, in Australia 2- Genus AnthotrocheEndl., four species, in Australia 3- Genus Crenidium Haegi, monotypic genus, in Australia 4- Genus CyphantheraMiers, 9 species, in Australia 5- Genus DuboisiaR.Br., four species, in Australia 6- Genus Gramnosolen Haegi, two species, in Australia 7- Genus Symonanthus Haegi, two species, in Australia 2- Tribe Nicotianeae tribe Dum. [1 Genus, 76 species] 1- Genus Nicotiana L., genus widely distributed, with 52 American species, 23 Australian, and one African.
2.4- Subfamily Petunioideae + Overview Molecular phylogenetics indicates that Petunioideae is the sister clade of the subfamilies with chromosome number x=12 (Solanoideae and Nicotianoideae). They contain calistegins, alkaloids similar to the tropanes. The androecium is formed of four stamens (rarely five), usually with two different lengths. The basic chromosome number of this subfamily can be x=7, 8, 9 or 11. It consists of 13 genera and some 160 species distributed throughout Central and South America. Molecular data suggest the genera originated in Patagonia. Benthamiella, Combera, and Pantacanthaform a clade that can be categorized as a tribe (Benthamielleae) that should be in the subfamily Goetzeoideae. + Genera: 1- Genus BenthamiellaSpeg., 12 species native to Patagonia 2- Genus BouchetiaDunal, three neotropical species 3- Genus BrunfelsiaL., around 45 species from the neotropics 4- Genus Combera Sandw., two species from Patagonia 5- Genus FabianaRuiz & Pav., 15 species native to the Andes 6- Genus Hunzikeria D'Arcy, three species from the southwest United States and Mexico 7- Genus LatuaPhil., one species from the south of Chile 8- Genus LeptoglossisBenth., seven species from western South America 9- Genus Nierembergia Ruiz & Pav., 21 species from South America 10- Genus Pantacantha Speg., monospecific genus from Patagonia 11- Genus CalibrachoaCerv. ex La Llave & Lex. consists of 32 species from the neotropics. The morphological data suggest this genus should be included within the Petunia. However, the molecular and cytogenetic data indicate both should be kept separate. In fact, Calibrachoahas a basic chromosome number x=9, while that of Petunia is x=7. 12- Genus Petunia (Juss.) Wijsman, 18 species from South America 13- Genus PlowmaniaHunz. & Subils, monotypic genus from Mexico and Guatemala
2.5- Subfamily Schizanthoideae + Overview The Schizanthoideae include annual and biennial plants with tropane alkaloids, without pericyclic fibres, with characteristic hair and pollen grains. The flowers are zygomorphic. The androecium has two stamens and three stamenodes, anther dehiscence is explosive. The embryo is curved. The basic chromosome number is x=10. Schizanthus is a somewhat atypical genus among the Solanaceae due to its strongly zygomorphic flowers and basic chromosome number. Morphological and molecular data suggest Schizanthus is a sister genus to the other Solanaceae and diverged early from the rest, probably in the late Cretaceous or in the early Cenozoic, 50 million years ago. The great diversity of flower types within Schizanthus has been the product of the species’ adaptation to the different types of pollinators that existed in the Mediterranean, high alpine, and desert ecosystems then present in Chile and adjacent areas of Argentina. + Genus 1- Genus Schizanthus Ruiz & Pav., 12 species originating from Chile.
2.6- Subfamily Schwenckioideae + Overview Subfamily Schwenckioideae has 4 genera, 30 species. Annual plants with pericyclic fibres, their flowers are zygomorphic, the androecium has four didynamous stamens or three stamenodes; the embryo is straight and short. The basic chromosome number is x=12. It includes four genera and some 30 species distributed throughout South America. + Genera: 1- Genus HeteranthiaNees & Mart., one species from Brazil 2- Genus MelananthusWalp., five species from Brazil, Cuba, and Guatemala 3- Genus Protoschwenckia Soler , monotypic genus from Bolivia and Brazil, some molecular phylogenetic studies have suggested this genus has an uncertain taxonomic position within the subfamily 4- Genus Schwenckia L., 22 species distributed throughout the neotropical regions of America.
3- The most important genera of the Family Solanaceae
The Solanaceae contain 98 genera and some 2,700 species. Despite this immense richness of species, they are not uniformly distributed between the genera. The eight most important genera contain more than 60% of the species, as shown in the table below. Solanum - the genus that typifies the family - includes nearly 50% of the total species of the solanaceas.