Rosaceae

From Wikipedia, the free encyclopedia

This article or section is in the middle of an expansion or major revamping. You are welcome to assist in its construction by editing it as well. If this article has not been edited in several days, please remove this template. Please consider not tagging with a deletion tag unless the page has not been edited in several days or the page has no content at all. This article or section was last edited by Lavateraguy (Contribs • Log) 2 seconds ago.

Rosaceae Fossil range: 110 Ma PreЄ Є O S D C P T J K Pg N ↓ Cretaceous - Recent
Flower of Crataegus oxycantha
Scientific classification
Kingdom: Plantae Division: Magnoliophyta Class: Magnoliopsida Order: Rosales Family: Rosaceae Juss.
Global distribution of Rosaceae

The Rosaceae or rose family is a large family of plants, with about 2,500 species in 90 genera (according to the Kew Royal Botanical Gardens). The name is derived from the genus Rosa. The largest genera are Sorbus, Crataegus and Cotoneaster (more or less 260 species each).

Contents 1 Distribution 2 Taxonomy 3 Description 4 Genera 5 Economic importance 6 External links

[edit] Distribution

The Rosaceae have a worldwide range, but are most diverse in the northern hemisphere.

[edit] Taxonomy

The family was traditionally divided into four subfamilies: Rosoideae, Spiraeoideae, Maloideae, and Amygdaloideae, primarily diagnosed by the structure of the fruits. More recent work has identified that not all of these groups were monophyletic. A more modern view comprises three subfamilies, one of which (Rosoideae) is has largely remained the same. A cladogram of the family according to APG II is shown below

	Rosoideae  Filipendula  Rosodae  Sanguisorbeae Potentilleae Colurieae Dryadoideae  Spiraeoideae  Lynothamnus Amygdaleae Sorbarieae Spiraeeae  Kerriodae  Kerrieae Osmarioneae  Pyrodae Gillenia Pyreae

[edit] Description

The Rosaceae can herbs, shrubs, or trees.

The flowers are generally showy.

The fruits of the Rosaceae come in varieties. The most common is a drupe but there are many others. Apples, pears, quinces, and most other members of the Maloideae are pomes, but some are capsules such as in Lindleya. The fruit of a strawberry is an achene held by a red ripe peg. Pomes and the strawberry are false fruits, while drupes are true fruits. Most fruits of the family are edible and are very important in flavoring such as strawberries, cherries and apples. Almonds are raised for their stones which are used as smoked or salted nuts.^{[dubious – discuss]} Apples and strawberries are hybrids of different species in the same genus.

[edit] Genera

See List of Rosaceae genera.

Identified clades include:

• Subfamily Rosoideae: Traditionally composed of those genera bearing small fruits, each of which is an achene or drupelet, and often the fleshy part of the fruit (e.g. Strawberry) is the hypanthium or the stalk bearing the carpels. The circumscription is now narrowed (excluding, for example, the tribe Dryadeae), but it still remains a diverse group containing 5 or 6 tribes and 20 or more genera. Rose, blackberry, raspberry, strawberry, Potentilla, Geum.
• Subfamily Spiraeoideae: Traditionally those genera which bear non-fleshy fruits consisting of five capsules. Now perhaps to be restricted to Spiraea and Sorbaria and their respective allies.
• Subfamily Maloideae (or Pomoideae): Traditionally this includes those genera (apple, cotoneaster, hawthorn, pear, quince, rowan, whitebeam, loquat, etc), whose fruits consist of five capsules (called "cores") in a fleshy endocarp, surrounded by the ripened stem tissue. This fruit is called a pome. To these are added the woody genera Lindleya and Vauquelinia, which share a haploid chromosome count of 17 (x=17) with the pomiferous genera, Kageneckia, in which x=15, and the herbaceous genus Gillenia (x=9), which is the sibling to the remaining maloids.
• Subfamily Amygdaloideae (or Prunoideae): Traditionally those genera whose fruits consist of a single drupe with a seam, two veins next to the seam, and one vein opposite the seam. Now extended to include the four genera Maddenia, Oemleria, Prinsepia and Prunus (plum, peach, almond, cherry, apricot).
• Tribe Dryadeae: Fruits are achene with hairy styles. Includes five genera (Dryas, Cercocarpus, Chamaebatia, Cowania and Purshia), most species of which form root nodules which host the nitrogen-fixing bacterium Frankia.
• Tribe Neillieae: Neillia (including Stephanandra) and Physocarpus.

Amongst these groups, Neillieae appears to be the sister group to Maloideae, and Dryadeae may be a sibling group to Rosoideae. Other genera, for example Kerria, appear not to belong to any of these groups.

[edit] Economic importance

The rose family is probably the third most economically important^{[citation needed]} crop plant family (after the grass family and the pea family), including apples, pears, quinces, medlars, loquats, almonds, peaches, apricots, plums, cherries, strawberries, raspberries, blackberries and cut roses among the crop plants belonging to the family.

[edit] External links

• Genome Database for Rosaceae at Washington State University
• Rosaceae at the University of Illinois.
• Rosaceae full family list at Plants For A Future - Species Database.
• Family Rosaceae Flowers in Israel
• Rosaceae of Chile, by Chileflora
• Family Rosaceae Diagnostic photos of many different species at the Morton Arboretum