The Suaedoideae are a subfamily of plants in the family

Amaranthaceae Amaranthaceae is a family of flowering plants commonly known as the amaranth family, in reference to its type genus ''Amaranthus''. It includes the former goosefoot family Chenopodiaceae and contains about 165 genera and 2,040 species, making it ...

(now including the former family Chenopodiaceae).

Description

The Suaedoideae have well-developed leaves. Except for genus '' Bienertia'', the leaves show a central and many lateral vascular bundles. The leaves are neither decurrent nor amplexicaul. The inflorescences are axillary cymes. The flowers are sitting free in the axils of bracts, with lateral bracteoles. The perianth consists of 5 tepals, which are more or less fused basally. 5 stamens are present. The seed encloses a spiral embryo, mostly without any perisperm.

Distribution

The Suaedoideae have a nearly worldwide distribution. They are important members of the vegetation of shores and salty inland habitats. They are especially common in dry (arid) regions.

Photosynthesis pathway

Among the species of Suaedoideae, there are nearly equal numbers of C₃-plants and C₄-plants. During the evolution of the subfamily, the C₄-photosynthesis pathway seems to have been derived from four independent origins: two times with Kranz C₄ anatomy in ''Suaeda'' section ''Salsina'' and ''Suaeda'' section ''Schoberia''. Two independent origins of non-Kranz C₄ systems are found in ''Bienertia'' and ''Suaeda'' section ''Borszczowia''. In these plants, the photosynthesis pathways are located without spatial separation in a "single cell C₄" type.

Systematics

According to phylogenetic research by Kapralov et al. (2006), the Suaedoideae are grouped in 2 tribes: * Tribus Bienertieae Ulbr., with only one genus: ** '' Bienertia'' Bunge ex Boiss., with 3 species: *** '' Bienertia cycloptera'' Bunge ex Boiss. *** ''

Bienertia sinuspersici ''Bienertia sinuspersici'' is a flowering plant that currently is classified in the family ''Amaranthaceae'', although it was previously considered to belong to the family Chenopodiaceae. ''Bienertia sinuspersici'' conducts C4 photosynthesis, b ...

'' Akhani *** '' Bienertia kavirense'' Akhani * Tribus Suaedeae, with only one genus: ** ''

Suaeda __NOTOC__ ''Suaeda'' is a genus of plants also known as seepweeds and sea-blites. Most species are confined to saline or alkaline soil habitats, such as coastal salt-flats and tidal wetlands. Many species have thick, succulent leaves, a character ...

'' Forssk. ex J.F.Gmel. (inclusive ''Alexandra'' Bunge and ''Borszczowia'' Bunge). With about 82 species, nearly worldwide. The genus can be further divided: *** subgenus ''Brezia'' (Moq.) Freitag & Schütze **** section ''Brezia'' (Moq.) Volk *** subgenus ''Suaeda'' **** section ''Alexandra'' (Bunge) Kapralow et al. **** section ''Borszczowia'' (Bunge) Freitag & Schütze **** section ''Physophora'' Iljin **** section ''Salsina'' Moq. s.l. (sensu Schütze et al.) **** section ''Schanginia'' (C.A.Meyer) Volk **** section ''Schoberia'' (C.A.Meyer) Volk **** section ''Suaeda''

References

External links