Nicotiana acuminata
Nicotiana acuminata var multiflora
Nicotiana acuminata is a species of the genus tobacco (Nicotiana ). Within the genus it is placed in the section Petunioides.
Description
Vegetative characteristics
Nicotiana acuminata is an annual plant, which quickly reached heights of growth of 0.5 to 2 meters. The stem is sticky golden or brownish hairs, the coat consists of inconspicuous, closely spaced, short trichomes. At the bottom of many long, ascending branches are often formed. Next up less branches are formed which are also shorter.
The plants are only a few hearty leaves formed, which also fade soon. The leaf blade reached lengths of 6 to 12 inches, mostly they are ovate to round - ovate shaped. The base is variable shaped, often both halves are unequal in shape. Forward the leaves are pointed. Both leaf surfaces are finely hairy, the upper surface is usually roughened significantly. The petioles are nearly as long as or shorter than the leaf blade.
The standing of the stems leaves have 10 to 25 centimeters long leaf blades that are shaped ovate to lanceolate or triangular. Petioles usually reach one third to one sixth of the length of the leaf blade. The uppermost leaves are becoming elongated lanceolate shaped, almost resting bracts.
Inflorescences and flowers
The inflorescences are Seems screws or elongated, flat panicles, the flowers open at night. The flower stems are 5 to 10 ( rarely 3-20 ) mm long, later extended to 10 to 20 (sometimes up to 25 ) mm.
The cup is 15 to 20 ( rarely 12 ) mm long, cylindrical, bell-shaped, sticky hairy. By blackish - green veins and long colorless membranous areas it acts striped. The edge of the cup is filled with non- designed, sleek, blunt teeth, of which the longest can be as long as the calyx tube. The crown is white on the outside slightly greenish tinge oily- metallic and fitted with purple stripes. It is solely the Kronsaums 25 to 90 millimeters long. Of a narrower area at the base is 8 to 35 mm long and 2-3 mm wide, the adjoining Kronschlund is nearly cylindrical, about as long as or longer than 1.5 times the area at the base. The coronary band measures 10 to 18 mm in diameter, is abducted and colored white on the inside. He is weak lobed, the Corolla lobe are margin entire to slightly sinuate.
The five stamens have either three different lengths on or just a single is slightly shorter than the other, they are not beyond the coronary band. All set at the base of the Kronschlunds and there are sometimes bent. In the lower part they are usually covered with fine hair to a length of several millimeters.
Fruit and seeds
The fruits are wide ovoid capsule having a length of 10 to 15 millimeters. You are surrounded by the expanded calyx. The seeds are bent kidney-shaped, or triangular, and are 0.9 to 1.0 millimeters long. They are gray - brown in color, have a ribbed mesh-like surface and contain a curved embryo.
Dissemination and locations
The distribution area of Nicotiana acuminata is in the middle altitudes in Chile and the Argentine Andes, except for the northernmost and southernmost areas. In the western United States, one of the varieties is naturalized. The sites have stony, gravelly or sandy soils. The plants are found on dry slopes, erosion, roadsides and in other disturbed sites in full sunlight or partial shade. In Chile, the species is found at altitudes of 100-3450 meters, in Argentina only to 1800 meters.
System
Within the genus Nicotiana Nicotiana acuminata is classified in the section Petunioides. All species of the section are annual herbs with a chromosome number of n = 12 and diploid set of chromosomes, most species are widespread in the south-west of the Andes. Most closely related Nicotiana acuminata Nicotiana attenuata with.
The genus is divided into three varieties:
- Nicotiana acuminata var acuminata
- Nicotiana acuminata var multiflora ( Philippi ) Rich
- Nicotiana acuminata var compacta Goodspeed