Nierembergia
Nierembergia repens
The white mug ( Nierembergia ) are a genus of flowering plants of the nightshade family (Solanaceae ). Most of the 20 species growing in western and southern areas of South America, one species grows exclusively in Mexico.
- 5.1 Literature
- 5.2 Notes and references
Description
Vegetative characteristics
The species of the genus Nierembergia are usually upright, bent down or prostrate -growing, herbaceous plants with a height of usually 20-40 (rarely 5-60 ) cm. Occasionally they form rhizomes, which in some species bulbous nodes. Only rarely are Nierembergia also shrubs with a height of 0.2 to 2 m. The endodermis has Casparian strip, a starchy vagina does not exist.
The leaves are sessile or with 2 to 4 mm long petioles. The leaf blades are 8-65 (rarely only three ) mm long and 0.6 to 4 ( rarely 0.3 to 19 ) mm wide. They are linear, elliptic, ovate, obovate or round shaped.
Inflorescences and flowers
The flowers appear singly or in loose, zymösen inflorescences. The pedicels are 1-12 mm (rarely 0.2 to 21 mm) long or lacking. The calyx is usually 11 to 18 mm, rarely 8-34 mm long, the corolla tube is funnel-shaped or bell-shaped and crossed by ten longitudinal ribs. The calyx tube is filled with calyx lobes, which can be shorter or longer than the tube, elongated, triangular, oval or linear are and have three to five veins. The zygomorphe crown is dish-shaped, usually 12 to 30 mm, rarely 8 to 70 mm long. The filiform corolla tube widens abruptly into a bell-shaped, funnel - or cup-shaped coronary band, the (rarely up to 33 mm and 6 ) reaches a diameter of 14 to 20 mm. The hem is decorated with five short and broad lobes, the lower third is occupied in most species with short glandular trichomes. These oils but from that are of particular importance for pollination by different bees.
All five stamens are fertile, the stamens are occasionally the same length, but usually three short and two longer stamens are formed, the latter carry larger dust bag. The stamens are hairy and glandular easily put on at the mouth of the corolla tube. The outline of the dust bag is circular (in this case a diameter of 0.6 to 1.45 mm ), or reniform (and then from 0.65 to 0.8 × 0.8 to 1.2 mm in size). The counters of the anthers are free in their lower half. The pollen grains are 45 to 70 microns relatively large, its shape has a large variation on. They are secreted glued individually or tetrads or pollen bales. Nectaries are absent. The scars are little head - shaped depressed, lobed or crescent -shaped. In the latter case, they often enclose the anthers with long, tapered ends.
Fruit and seeds
The fruits are capsules that are barely above the calyx tube out. They contain from 20 to 100 small polyhedral seeds are from 0.9 to 1.9 x 0.7 to 1 × 0.7 to 0.9 mm. The cotyledons are slightly longer than the rest of the embryo.
Other features
The chromosome number has been studied only four species, the base number was x = 8 or x = 9 In Nierembergia linariifolia the first time the substance Pyrrole -3- Carbamidin has been demonstrated by which the plant among other things, cattle, sheep, goats, horses and rabbits is toxic. Three other glycosides were detected in Nierembergia rigida.
Occurrence
Most species of the genus are widespread in western and southern areas of South America, only Nierembergia angustifolia grows exclusively in a disjunct distribution area from the rest area in Mexico. The distribution area with 15 species located in Argentina, with Nierembergia linariifolia reached a kind of northern Patagonia.
System
Within the genus about 20 species can be distinguished. Select by:
- Nierembergia angustifolia Kunth
- Nierembergia aristata D. Don
- Nierembergia browallioides Griseb.
- Nierembergia calycina Hook.
- Nierembergia ericoides Miers
- Nierembergia graveolens A. St. - Hil.
- Narrow- white mug ( Nierembergia linariifolia Grah. )
- Nierembergia micrantha Cabrera
- Nierembergia pinifolia Miers
- Nierembergia pulchella Miers
- Crawling white mug ( Ruiz et Pav Nierembergia repens )
- Nierembergia rigida Miers
- Nierembergia rivularis
- Shrub White cup ( Nierembergia scoparia Sendtn. )
- Nierembergia tandilensis ( Kuntze ) Cabrera
- Nierembergia tucumanensis Millan
- Nierembergia veitchii Hook.
The type species is Nierembergia repens.
Use
The types Nierembergia linariifolia, Niermebergia repens and Niermebergia scoparia and possibly one or two other types are drawn as ornamental plants.