Solanum rostratum

Sting - nightshade (Solanum rostratum )

The sting - nightshade (Solanum rostratum ) is a species in the genus of the nightshade (Solanum ). The original range of the species is in Mexico and the United States, in many other areas, the species is introduced, where they can be found as a weed in disturbed habitats.

Description

Habitus and sheets

Sting - nightshade are highly branched annuals, herbaceous plants, which are covered with trichomes with star-shaped heads. The shoot axis is thick up to 1 cm and is equipped with highly tapered or with a wide base, yellow spines that are up to 38 mm long. The trichomes on the stem axis are stalked up to 1 mm long, usually, however, directly -mounted. Solanum rostratum form from taproots.

A sympodial unit consists of two sheets that are almost in pairs mostly. The leaves are ovate to broadly ovate with rounded or blunt lobes. The leaf blade is 7 to 16 cm long, busy along the main veins with spines and hairs on both leaf surfaces. The petiole is 1/3 to 2/3 as long as the blade and is also covered with spikes.

Inflorescences and flowers

The inflorescences are internodal, are 4-11 cm long and consist of seven to twelve flowers. The calyx is fused together during the flowering period only at the base and divided into linealische cloth with a length of 6 to 10 mm, the calyx tube is bell-shaped, 1.5 to 2.5 mm long, densely hairy, bristly or sometimes with thorns occupied. The yellow corolla is pentagonal shaped between the petals a comprehensive, wrinkled tissue is formed. It has a diameter of 2.3 to 3.5 cm, the outside is hairy fluffy. Exist in two different forms of a flower stamens. The long stamens are 1.0 to 1.4 cm long, arcuately curved and often colored red or purple. The shorter stamens are 6-8 mm long and yellow. The hairless ovary is closely embedded in the developing calyx tube, the pen is 1.0 to 1.4 cm long, slender and often dyed purple. The stamp is not enlarged. In the distribution area, the plants bloom throughout the summer until well into the autumn.

Fruit and seeds

The fruits are spherical berries with a diameter of 9 to 12 mm, which are addressed to slightly erect, 8-13 mm long pedicels are. The during the fruit ripening slightly enlarging calyx has several constrictions and is studded with spines, which are usually slightly longer than the spines on the stem axis. At maturity, the berry dries up and jumps on to release the 40 to 80 seeds. These are flat ovoid, 2.0 to 2.6 mm long, the surface is feingrubig, the sides are flat or corrugated.

Distribution and habitat

The original range of the species probably ranges from the area north of Mexico City beyond Mexico to the Great Plains of the United States. In many other areas, such as Australia or Russia, the plant was introduced and can be found there also. Most Solanum rostratum grows in open, often disturbed habitats, can adapt to many different soil types and is a weed on roadsides and überweidetem grasslands.

System

Solanum rostratum is classified nightshade (Solanum ) in the series Androceras the section Androceras within the Leptostemonum clade of the genus.

Swell

• Solanaceae Source: species profile of Solanum rostratum. National History Museum, London. Online. Retrieved on September 15, 2007