Maloideae
Cultivated apple (Malus domestica)
The pome fruit crops ( Pyrinae ) are a group of plants in the rose family ( Rosaceae ). It includes many types of fruit such as apples and pears with the characteristic apple fruits. Long they have been managed as a separate subfamily Maloideae.
Description
The representatives of the Pyrinae are deciduous, winter or evergreen shrubs or small to medium-sized trees. They are unarmed or carry sprout spikes. The leaves are alternate, usually simple, rarely lobed or pinnate. The stipules are free and mostly obsolete ( soon falling).
The flowers are fünfzählig, usually hermaphrodite and have a pitcher -shaped flower cups. The discus is dry or nectar making. The five sepals remain on the fruit stand or fall off. The five petals are white, pink or red. The stamens are numerous ( 20 to 30, rarely 10 to 60 ). There are usually five carpels, often they are four to two or even reduced one. At maturity the carpels are fused at different heights to parchment- like stone and with the thickened fleshy flower axis, and thus form an apple fruit. Each carpel containing one to many seeds.
Most genera cyanogenic glycosides form, especially amygdalin ( in the seeds ) and Prunasin ( in other plant parts ). Sorbitol is an important storage and transport of carbohydrates.
The Pyrinae are characterized by the basic chromosome number x = 17.
Hybridization
The Pyrinae often occurs intergeneric hybridizations. This is documented for 16 species. Also for the evolution of Pyrinae may have played a significant role hybridization.
System
The pome fruit crops were long out as one of the four subfamilies of Rosaceae. Molecular genetic studies have shown that they form a group within the Spiraeoideae. Potter et al. the group have therefore defined as subtribe Pyrinae. Together with the genera Kageneckia, Vauquelinia and Lindleya they form the tribe Pyreae.
- Juneberries ( Amelanchier )
- Aria
- Chokeberry (Aronia )
- Ornamental quince ( Chaenomeles )
- Chamaemeles
- Chamaemespilus
- Cormus
- Zwergmispeln ( Cotoneaster )
- Hawthorn (Crataegus )
- Quince ( Cydonia )
- Dichotomanthes
- Docynia
- Docyniopsis
- Loquats ( Eriobotrya )
- Eriolobus
- Hesperomeles
- Heteromeles
- Apples (Malus )
- Melacomenes
- Loquat ( Mespilus )
- Osteomeles
- Peraphyllum
- Photinia ( Photinia )
- Pseudocydonia
- Firethorn ( Pyracantha )
- Pears (Pyrus )
- Rhaphiolepis
- Flour berries ( Sorbus )
- Stranvaesia ( usually be counted to the Photinia )
- Torminalis
Evolution
The taxa of Pyrinae likely to be caused by a rapid, long ago Radiation. Fossil are the first representatives, Amelanchier, Crataegus and Photinia from the early Middle Eocene, around 48 to 50 million years before present, known. This rapid radiation is attributed to the formation of the fleshy apple fruit and the associated propagation by animals. Hybridization has also played a role in evolution.
Documents
- Siegmund Seybold (ed.): Schmeil Fitschen - interactive ( CD -Rom ), Quelle & Meyer, Wiebelsheim 2001/2002, ISBN 3-494-01327-6