Poales
Poales is a taxonomic order of flowering plants in the monocotyledons. The order includes families of plants such as the grasses, bromeliads, and sedges.
| Poales Temporal range:
| |
|---|---|
| |
| Scientific classification | |
| Kingdom: | |
| Division: | |
| Class: | |
| Order: | Poales
|
| Families | |
|
See text | |
Most Poales are wind-pollinated, and so lack the colour and scents of most flowering plants. The bromeliads, however, produce large fruits which are eaten by animals and so act as seed-spreaders.
The earliest fossils of Poales date to the late Cretaceous period, about 66 million years ago. Some suggest the origin of the group may be 115 million years ago in South America.[1] The earliest known fossils include pollen and fruits.
The flowers are typically small, enclosed by bracts, and arranged in inflorescences (except in the genus Mayaca, with solitary terminal flowers). The flowers of most species are wind pollinated. The seeds usually contain starch.
Among monocots, the Poales come second to the orchids in number of species. But in economic terms, they are far more important. In fact, the true grasses (Poaceae) produce by far the most important grains eaten by humans and other animals.
One recent classification lists these families: [2]
- order Poales
- family Anarthriaceae
- family Bromeliaceae
- family Centrolepidaceae
- family Cyperaceae
- family Ecdeiocoleaceae
- family Eriocaulaceae
- family Flagellariaceae
- family Joinvilleaceae
- family Juncaceae
- family Mayacaceae
- family Poaceae
- family Rapateaceae
- family Restionaceae
- family Thurniaceae
- family Typhaceae
- family Xyridaceae
Diversity and uses
changeThe Poales are the most economically important order of monocots and possibly the most important order of plants in general. Within the order, by far the most important family economically is the family of grasses (Poaceae, syn. Gramineae), which includes barley, maize, millet, rice, and wheat. It is also the largest family in the order, far outnumbering the other families:
- Poaceae: 12,070 species
- Cyperaceae: 5,500 species
- Bromeliaceae: 3,170 species
- Eriocaulaceae: 1,150 species
References
change
- ↑ Bremer K. 2002. Gondwanan evolution of the grass alliance of families (Poales). Evolution 56: 1374–1387. Abstract
- ↑ Angiosperm Phylogeny Group 2009. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG III. Botanical Journal of the Linnean Society 161 (2): 105–121.