The petunia, scientifically also called Petunia, is a genus of plants within the Solanaceae, the nightshade family. The petunia unites in about 16 different species, with the garden petunia being one of the most important ornamental plants. The genus of petunia was established by Antoine-Laurent de Jussieu in 1803. The genus name of petunia is derived from the word petun, which comes from the Brazilian word of the indigenous people of Brazil for tobacco.
Petunia species are subordinated to herbaceous plants. Thus, the above-ground part of the plant is characterized by simple, often sticky hairy trichomes. the leaves of petunias are arranged in pairs or alternate and can be stalked or stalkless. Also typical of the named plant genus are the simple and entire margined leaf blades.
The flower of petunia is characterized by a solitary, single-branched and cymose inflorescence. It is accompanied by a pair of almost congruent bracts. The hermaphrodite, five-petaled flowers are equipped with a double perianth, which are almost radially symmetrical. The petunia flower emits a more or intense fragrance, depending on the species. The knob cover of petunia is roof tile-like, also called imbricate. In addition, they five sepals, which are only short fused. The petunia’s corolla is often strikingly colored and is characterized by a funnel or cup shape.
The capsule fruits of the petunia spring open septum-cleft and have a large number of seeds. These themselves are usually round or angled. The testa, that is, the seed coat is of reticulate shape, which is due to the vertical position of the corrugated walls of the seed surface.
Most Petunia species are found in temperate or subtropical climates of South America. However, they are particularly widespread in Brazil, Uruguay, Argentina, Paraguay or even Bolivia. Petunia axillaris is most commonly found in these regions.
Due to the fact that petunias are distinguished by their large, open flowers, it is considered a particularly popular ornamental plant and is therefore often found as a decoration.
The first cultivated plant is said to have been Petunia axillaris, which was recognized from an article published in 1825 in Curtis’s Botanical Magazine. The garden petunia available today is a hybrid of two different petunia species.
In 2007, the Finnish Food Safety Authority detected a genetic modification in an orange-flowered petunia variety. Cultivation of this variety is banned in Europe and the USA. The evidence from the Finnish investigation was also confirmed by the German Federal Office of Consumer Protection and Food Safety. The genetic modification is said to originate from a transgene of a genetically modified petunia, to which a gene from a corn plant was inserted in 1986 to produce an orange flower coloration. The ban on cultivation in the USA and Europe is intended to prevent unintentional spread, as the genetic modification of the plant is not always recognizable from the orange flower.