Dear friends I sincerely would like to appeal to those who want to upgrade their health must go for herbals and use herbal preparations as far as possible. By doing so our body's toxicity will be reduced. Our health will be maintained and improved. Our life span too will be lengthened.
Herbs are Almighty's wonder gifts. We must be prepared to use them along during our lives.
English Common Names (Yellow) evening primrose. Archaic names: tree primrose, scurvish, scabbish (scabish), king's cureall, nightwillow herb, sundrops, tree primrose, fever plant.
The name evening-primrose is optionally hyphenated. Evening primrose isn't a "primrose," a name best applied to the genus Primula. The "evening" in the name relates to the fact that the flowers of many of the 125 species of Oenothera open in the evening and release a scent that attracts moths for pollination.
French Common Names
Onagre bisannuelle (commune).
This species is a perennial with a fairly short bloom period. Its flowers may be seen in May and June, with the peak being mid-May in Kansas. The individual flowers are only around for a day or so, which is common for most members of the evening primrose family. They first open in the evening and wither the following day.Pollination of this species is done by large hawkmoths and possibly also by hummingbirds. The flowers of the evening primrose family typically have a large X-shaped pistil (red arrow), which projects beyond the stamens. This distinctive feature is very easily seen with a close look at any blossom. The leaves of this plant are narrow and lance-shaped. They are up to 6 inches long. Most varieties have a silvery sheen due to the many short hairs on the surface of the leaf. Evening Primrose grows in a low sprawling manner, unlike some of its cousins which may get 5 feet tall.
The seed pod of this species is very distinctive. It has four papery "wings" on it that allow the pod to be blown about by the wind, helping to scatter the seeds. This is the seed pod of Missouri Evening Primrose.
Missouri evening primrose is a sprawling, Missouri native plant which occurs on limestone glades and bluffs and rocky prairies in the Ozark region south of the Missouri River. Typically grows 6-12" tall and features very large (3-5" across), solitary, 4-petaled, mildly fragrant, bright yellow flowers which open for only one day (usually open late afternoon and remain open until the following morning). Flowers arise from leaf axils and are generally upward-facing, but sometimes rest on or touch the ground. Long spring to summer bloom period. Flowers are followed by somewhat unique, winged seed pods (2-3" long). Narrow, lance-shaped leaves. This species was formerly called (and is still often listed for sale as) Oenothera missouriensis.
Morphology
Oenothera biennis is a biennial (as the name suggests) or short-lived perennial herb producing strong fleshy roots and a basal rosette of lanceolate leaves in the first year. In the second year the stem grows to 1-2 m tall and develops a spicate inflorescence of 4-parted, yellow, tubular flowers.
The fruit is a capsule containing many seeds which mature in the fall. The seeds are very small (ca. 0.5 g/1000), but a single plant can easily produce 150,000. The pollen of many, if not all species of Oenothera, is unusual in having protruding apertures and viscin threads.
Classification and Geography
Evening primrose, a native of North America, is found in all provinces of Canada, but is more frequent in the east than the west. The species extends south to Florida and Mexico.
Many texts recognize var. canescens T. & G., with dense grayish pubescence, as the predominant plant of western North America, while the eastern plants are referable to var.biennis. The classification of the transcontinental O. biennis and related species of both North America and Eurasia is, however, very complex. Cytogenetic races of evening primrose are sometimes segregated as distinct species, although these are usually difficult to distinguish morphologically. Oenothera biennis is a complete translocation complex-heterozygote, with two sets (the"complexes") of seven chromosomes maintained by a system of balanced lethal genes. This type of inheritance is known in a few other genera, but was first described in O.biennis, and is the classical example of the phenomenon discussed in evolution and genetics courses. At meiosis, translocations Note[note 1] link the chromosomes into a ring of 14, but zig-zag (alternate) separation of the chromosomes generates the original parental sets.
Lethal factors kill the pollen carrying one of the sets (so that there is 50% pollen fertility), and ovule lethal factors limit survival to the set of chromosomes complementary to that in the pollen. Self-pollination generates offspring with the two chromosome complements found originally in the maternal plant. The permanent hybrid vigour resulting from the combination of two quite different genomes is thought to explain the success of evening primrose as a colonizing species.
While it is clear that O. biennis is the chief Oenothera species that has been grown as a medicinal oilseed, related species have also been cultivated, often unknowingly. Other species from which cultivars have been derived include O. glazioviana Micheli ("O.lamarckiana" of many authors) and O. parviflora Micheli.
Evening primrose is a frequent weed of roadsides, waste places, and abandoned land, often found in light sandy and gravelly soils. It commonly occurs in association with early successional, biennial and perennial weeds.
Medicinal Uses
Evening primrose extracts were used medicinally by both Indians and early settlers. In Europe during the early 1600s it was called "King's Cure-all." An infusion of the whole plant was thought to counter asthmatic cough, gastro-intestinal disorders, and whooping cough, and to reduce pain. Poultices were used to treat bruises and wounds
Evening primrose has attracted great interest for its seed oil, used medicinally as a nutritional supplement. The health value of the seed oil resides in an unusual polyunsaturated fatty acid, g-linolenic acid (gamma-linolenic acid) or simply GLA. The seeds contain 17-25% oil, of which only 7-10% is GLA, although climate and maturity affect oil content and qualitative composition, as well as overall yield.
GLA is one of the so-called essential fatty acids needed by humans for maintenance of cell functions. It is a precursor in the biosynthesis of prostaglandins, especially prostaglandin E1, a hormone-like substance that has been clinically shown to regulate metabolic functions in mammals; it affects cholesterol levels, dilates blood vessels, reduces inflammation, and has additional effects.
GLA is thought to be important for development of brain tissue and other tissue growth, and nature seems to provide for human infants with high levels of GLA in human milk. GLAis a normal conversion product of linoleic acid, a major constituent of most vegetable oils, so that it would appear that humans should not experience a shortage.
Nevertheless, some people, perhaps 10-20% of the population, evidently do not have adequate levels, even when receiving large amount of linoleic acid. The deficiency seems due to lack of an enzyme that metabolizes GLA from linoleic acid, so that there is a deficiency of GLA in the blood.
Useful for treating atopic eczema, GLA has therapeutic promise for premenstrual syndrome, diabetes, multiple sclerosis, alcoholism, inflammation, heart disease and stroke. Rubbing GLA into the skin is thought to be an alternative route of assimilation, and so cosmetic preparations sometimes incorporate GLA.
Pharmaceutical and food companies are developing GLA-containing supplements and specialty foods for infants, the elderly, and people with health problems.
Toxicity
Side effects of consumption of GLA-fortified foods and supplements have been documented, so that use should be guided by doctors and pharmacists.
Chemistry
Gamma-linolenic acid, the constituent of chief medicinal interest, is discussed above.
Non-medicinal Uses
There are ornamental forms of Oenothera biennis with attractive habit and flowers. There are also forms with fleshy edible roots, used as a vegetable, which were more commonly grown in the nineteenth century than today. Evening primrose leaves, shoots, roots, and seed pods were consumed by American Indians as food.
Agricultural and Commercial Aspects
The most significant current economic value of the species lies in its use as a diversification crop. Although GLA has been obtained by fermentation of some yeasts and other fungi, and from currants (Ribes species), the chief commercial sources are evening primrose and borage (Borago officinalis L.).
Companies have engaged in a boastful debate about the comparative efficacy of GLA in their preparations made from evening primrose on the one hand, and from borage on the other. Whether borage or evening primrose is more competitive for GLA production depends on climatic and edaphic factors at a particular location.
In Canada, both species are grown. Borage has a higher GLA content, but non-shattering cultivars are not grown in Canada, so that harvest is difficult. Borage is much more suitable for the Canadian prairies, where available cultivars of evening primrose do not overwinter reliably.
However it isn't essential to grow evening primrose as a biennial: in Eastern Canada it is often started in greenhouses in mid-winter and transplanted to the field where it is grown as an annual.
As a cultivated plant, evening primrose is tolerant of a variety of soil types and a range of pH, but soils that are prone to crusting after rains and waterlogged soils should be avoided. If planted at too high a density (150 plants m2) the plants may not bolt.
Evening primrose crops are raised in temperate areas of northern and eastern Europe, North America, and Australasia. US production is centered in North and South Carolina, Texas, and Oregon.
Canadian production is centered in Nova Scotia and Ontario. Experimental production in Manitoba has been disappointing. Annual world production of seed has increased at least 20 fold in the last 20 years, and is currently about 4,000 tonnes.
Combined US, and Canadian annual production is less than 200 tonnes. In good market years, several hundred ha of evening primrose may be grown in Canada.
Oenothera biennis (evening primrose)
Wild evening primrose plants shed their seeds when a pod matures, and since the pods don't mature simultaneously, harvest of seeds is difficult. Nevertheless, seed is gathered from wild plants in northeast China.
Most modern evening primrose cultivars have non-shedding pods, which has simplified harvest and reduced seed loss. Crop yields of over 2 tonnes/ha have been recorded in Nova Scotia, although much lower yields are frequent. In Ontario, depending on the rather volatile market and variable production, a hectare may result in a gross financial return of $1,000-2,000.
The future of evening primrose as a pharmacological crop in Canada is uncertain because of competition from other countries and the unreliability of the present market. Hemp (Cannabis sativa L.) is attracting considerable interest as a new crop in Canada, to be grown not only for fibre but also for its high-GLA seed oil.
Still another potential source of competition is the possibility that genetic engineers will splice the capacity to produce GLA into crops such as canola (Brassica species). Certainly the demand for GLA will continue to grow, and at least from time to time it may be anticipated that evening primrose crops will be grown in Canada on a contracted basis. With respect to climate and native germplasm, Canada is in a good position to develop its share of the evening primrose market.
Myths, Legends, Tales, Folklore, and Interesting Facts
Some evening primrose seeds have been shown to live to 80 years in the soil.
Hugo de Vries (1848-1935) was a world-famous student of evolution who, at the beginning of the 20th century, theorized that new species arise by spontaneous changes in individuals called mutations (Charles Darwin had earlier learned that such changes (called "sports" at the time) occur, but did not appreciate their importance for the mechanism of evolution). Unfortunately for de Vries, he chose evening primrose to demonstrate his theory. Later, scientists learned that the odd genetic system of evening primrose was responsible for the generation of altered individuals that de Vries was labelling as mutations and that this system did not occur in many other plants. As a result, his theory was discredited, although de Vries did contribute substantially to evolutionary theory.
Action, Medical Uses, and Dosage An ointment made by boiling the twigs, leaves, and bark, in lard or tallow – or a strong decoction of these – has been found very efficient in curing tetter, milk-scall, and other cutaneous affections of infants. Collect the material when the plant is in flower. In fomentation, or when recent, the bruised leaves form an excellent application to ulcers. Internally, oenothera has been used for a number of purposes, and its specific field of action seems none too well established. It has, however, been accorded a place in the treatment of gastro-intestinal disorders of a functional character. Dr. Scudder points out as the indications for it, a sallow, dirty skin, with full and expressionless tissues, an expressionless face, an unnatural and large tongue, having the sallow, dirty hue of the skin, and the patient’s mentality is of a gloomy an despondent character. Under these conditions he has employed it with success in dyspepsia, hepatic torpor, splenic an dimesenteric glandular enlargements, and in female disorders, with torpor and pelvic fullness.
This is the seed pod of Missouri Evening Primrose.
Evening Primrose grows in a low
This is the seed pod of Missouri Evening Primrose.
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