The Pooideae are the largest subfamily of the grass family Poaceae, with about 4,000 species in 15 tribes and roughly 200 genera. They include some major cereals such as wheat, barley, oat, rye and many lawn and pasture grasses. They are often referred to as cool-season grasses, because they are distributed in temperate climates. All of them use the C3 photosynthetic pathway.
The Pooideae are the sister group of the bamboos within the BOP clade, and are themselves subdivided into 15 tribes.
Paniceae is a large tribe of the subfamily Panicoideae in the grasses (Poaceae), the only in the monotypic supertribe Panicodae. It includes roughly 1,500 species in 84 genera, primarily found in tropical and subtropical regions of the world. Paniceae includes species using either of the C4 and C3 photosynthetic pathways, as well as presumably intermediate species. Most of the millets are members of tribe Paniceae.
The tribe is subdivided into seven subtribes, but some genera are as yet unplaced (incertae sedis). Species in the Paniceae have an ancestral chromosome number (monoploid number) of x = 9, while species with x = 10 formerly included are now recognised as separate tribe, Paspaleae.