Digitalis lanata Ehrh.
Digitalis lanata Ehrh.
2807 (5). D. lanata Ehrh., Beitr. Naturk. VII (1792) 152; Boiss., Fl. Or. IV (1879) 430; Vel., Fl. Bulg. (1891) 422; Hayek, Prodr. Fl. Penins. Balc. II (1929) 175; Heywood, Fl. Eur. Ill (1972) 241 — Вълнест напръстиик Fam: Scrophulariaceae Juss.
Genus: Digitalis L.
Species: Digitalis lanata Ehrh.
English Name: Wooly foxglove or Grecian foxgloveDescription:
Perennial or annual plants. Rhizome brown, woodened, horizontal, branched with numerous additional roots. Stems 30 - 80 (-100) cm tall, single or several, erect or more rarely rose slightly to, cylindrical, smooth, often reddish violet colored, unbranched, leaved evenly with dry and declining at the beginning of flowering leaves at the base of the stem; at the bottom and in the middle usually naked, naked to the inflorescence or rare cloth; inflorescence axis densely covered with long hairs. Basal and lower stem leaves 6 - 12 (-20) cm long and 1.5 - 3 (-3.5) cm wide, elongated lanceolate to lance linear obtuse or tapered, at the base narrowed and gradually passing in long stems, mostly entire, rarely slightly wavy edge or with several small teeth, absently covered with multicellular and glandular hairs, with clearly noticeable main vein and 3 - 4 lateral veins leaving from the base of the main vein and curved at the tip; middle and upper lanceolate or linear lanceolate, 4 - 10 cm long and 1 - 2 cm wide, sharp, squatting at the base, on the edge of the lamina ciliates. The inflorescence 15 - 25 (-30) cm long, with many blossoms, cylindrical pyramidal cluster; inflorescence axis glandular hairy; bracts, blossom stems and the shares of the calyx densely covered with long, whitish hairs. Blossoms bent down or spread out horizontally; blossom stems 2 - 3 mm long. Bracts oblong lanceolate or linear lanceolate, sharp. The calyx shares 6 - 10 mm long, lanceolate, sharp, without membranous edge. Corolla 20 - 30 mm long, white or whitish with a network of reddish-brown, curved up shares; bottom with very small triangular side shares and significantly larger, 8 - 13 mm long, white, elongated triangular to ovoid average share, almost equal in length gum tube. The box 8 - 12 mm long, cone, covered with glandular hairs. Seeds 1.1 - 1.3 mm long and 0.6 mm wide, yellow-brown, irregularly tetrahedral prism.
„Флора на Република България”, том Х, БАН, София, (1995)* * *
Digitalis lanata (often called the Woolly Foxglove or Grecian Foxglove) is a species of foxglove. It gets its name due to the texture of the leaves. Digitalis lanata, like some other foxglove species, is highly toxic in all parts of the plant. Even the ingestion of small amounts by humans can be fatal particularly for children[clarification needed][1] . Symptoms of digitalis poisoning include nausea, vomiting, severe headache, dilated pupils, problems with eyesight, and convulsions at the worst level of toxicity. The plant is also harmful to other animals. In some cases it is considered invasive or a noxious weed. Minnesota is one of the few places that consider it invasive as noted by the Western Weed Society. It is in leaf all year, in flower in June and July, and the seeds ripen in early-mid September. The flowers are hermaphroditic (having both male and female organs). Bees pollinate the flowers.[citation needed]
Description
The plant commonly grows from 0.3 to 0.6 meters in height, or about 13 to 26 inches. The plant prefers part shade and humus rich soil. The plant also prefers sandy, loamy, and clay soils. It can grow under dry or moist conditions. Seeds develop in pods that have small hooks, enabling the pods to be transported by animal fur or clothing. The elongated leaves are mid–green, wooly, veined, and covered with white hairs on the underside. They also have a very bitter taste. There is a tidy rosette before the spike goes up, and it is neatly arranged around the purple-tinged stems. The flowers are tubular and bell shaped with a creamy-white color and purplish-brown netting as well as a long broad lip. The flowers usually bloom in the second year. Both flowers and stems are also woolly or hairy as well as pretty.
Distribution
It is found mostly in Eastern Europe. One of the biggest populations can be found near Bácsalmás in Hungary. Even though it is native to Europe, the plant can now be found throughout the world, growing in woodland areas, on roadsides, and in mountainous regions. In North America, it can be found mostly in the Northeast and Southwest regions. It is cultivated mainly in New York, Washington, Utah, and Colorado.
Physiology
The species is adapted to sunny and warm sites on dry, mostly on sandy and stony loamy soil. During the first vegetation period, only the leaf rosette is developed, flowering follows during the second vegetation period. Therefore, especially during the first year, a high resistance against water stress (drought stress) has to be expected. Indeed, the leaves remain turgescent even under very low leaf water potential, due to osmotic adaptation by synthesis of non ionic substances in the leaves. The drought induced diminishing of photosynthesis is reversible after a few hours following watering of the plants.[2] Drought stress also reduces the quantum yield of photosystem 2.[3] More than 70 bitter glycosides with cardiac activity, with 5 different aglyconees Digitoxigenin, Gitoxigenin, Digoxigenin, Diginatigenin and Gitaloxigenin in the leaves act as a protection against herbivores.[4] Yield and concentration of these cardiac glycosides can be enhanced by greenhouse cultivation by enhanced temperature and enhanced carbon dioxide concentration.[5]
Medical uses
Digitalis lanata contains a powerful cardiac glycoside that may be used by patients with heart conditions. Digoxin (Digitalin) is a drug that is extracted from Digitalis lanata. It is used to treat some heart conditions such as atrial fibrillation. It slows atrioventricular conduction so that the heartbeat slows down and very slightly increases contraction power (positive inotropic effect). Because of the improved circulation in congestive heart failure caused by fast atrial fibrillation, the kidneys can function better, which stimulates the flow of urine, which lowers the volume of the blood and lessens the load on the heart. This is the effect that was first described when the plant was discovered as a medicine (Withering 1785). Digitalin was not discovered until the mid-19th century by two French scientists Homolle Ouevenne and Theodore Ouevenne. It wasn’t until 1875 that Oscar Schmiedberg identified digoxin in the plant.[6] It was first isolated in the 1930s in Britain by Dr. Sydney Smith.[7][8] Back then it was used to treat ulcers in the lower abdomen, boils, headaches, abscesses, and paralysis, and externally healing wounds. Today it is still extracted from the plant because synthetis is quite expensive and difficult. However, it is becoming less frequently used due to the narrow therapeutic margin and high potential for severe side effects. Digoxin is being replaced by newer drugs including beta blockers, angiotensin-converting enzyme inhibitors, and the calcium channel blocking agents. As new pharmacotherapeutic agents arise, the use of digitalis preparations will continue to decline. There are also other commercial uses for Digitalis lanata other than heart conditions. For example, in South America the powdered leaves are used to relieve asthma, as sedatives, and as diuretics. In India it is used as an ointment that contains digitalis glycosides used to treat wounds and burns.
From Wikipedia, the free encyclopedia* * *
Flowering Time: Blooms: V - VI, fruitful: VII - VIII.
References: „Флора на Република България”, том Х, БАН, София, (1995)., Wikipedia, the free encyclopedia
Distribution in Bulgaria: In grassy and rocky places in the shrubs and sparse forests in lowlands and mountains from sea level up to about 1500 m altitude. (Conspectus of the Bulgarian Vascular Flora) = conspectus&gs_l= Zlc.
Distribution: Southeastern Europe (Balkan peninsula), southern Hungary, western and southern Romania.
Conservation status and threats: not protected species in Bulgaria by the Biodiversity Law. Законодателство на Република България: Закон за биологичното разнообразие
Medical plant: yes, it is - http://lex.bg/laws/ldoc/2134916096
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