Vous êtes ici : Publications Tela Botanica > Synthèses des forums > Synthèses de niveau 1 > Ledum palustre - Lède des marais (Ericaceae)
Selon TUTIN et al (1972), en Europe, il n'y a qu'une seule espèce polymorphe de Ledum avec la présence de deux sous-espèces :
Ledum palustre L., Sp. Pl. 391 (1753)
Arbuste à tiges érigées ou décumbentes (jusqu'à 1,20 m de hauteur) et à jeunes rameaux ferrugineux-tomenteux. Feuilles persistantes, alternes et courtement pétiolées, linéaires ou oblongues (12-50 sur 1,5-12 mm). Inflorescences terminales en corymbe (= fausse ombelle), à fleurs nombreuses. Fleurs à 5 petits sépales soudés sur la plus grande partie de leur longueur, 5 pétales libres (4-8 mm) blancs et rayonnants, à très longues étamines saillantes (8 à 10 en moyenne) dont les anthères ne présentent pas d' appendices et à ovaire verruqueux-glanduleux. Le fruit est une capsule septicide.
La sous-espèce "palustre" a des feuilles plus linéaires à nervure médiane bien visible à la face inférieure, tandis que la sous-espèce "groenlandicum" a des feuilles elliptiques-oblongues à nervure inférieure cachée par un tomentum roux.
Cf. TUTIN T.G., V.H. HEYWOOD, N.A. BURGES, D.M. MOORE et D.H. VALENTINE (ed.), 1972 - Flora Europaea, 3 (Diapensiaceae to Myoporaceae) : 9-10.
Parties utilisées : Feuilles, sommités fleuries.
Principes actifs et emplois : Un extrait fluide de lédon s'est montré hypotenseur, renforçateur du péristaltisme intestinal, diurétique, cicatrisant (POLVEKTOVA, 1962).
Il va sans dire que le tanin peut intervenir à ce dernier titre.
Serait-ce en raison de l'effet diurétique que la plante est utilisée dans plusieurs spécialités allemandes à titre d'antirhumatismal ?
La feuille possède des propriétés antitussives (ANDRONOVA, 1972), expectorante (WEISS).
L'huile essentielle, déjà étudiée (SCHANTZ & HILTUNEN, 1971), se montre anti-inflammatoire (KLOKOVA et al, 1983). Les composants biologiquement actifs de la plante ont fait l'objet d'une publication (KONOVALOVA et RYBALKO, 1987) avec un effet inhibiteur de la biosynthèse des prostaglandines in vitro (WAGNER et al, 1986).
Cf. BEZANGER L., M. PINKAS, M. TORCK et E. TROTIN, 1990 (2ème édit.) - Plantes médicinales des régions tempérées. Edit. Maloine.
et :
C'est aussi un petit arbuste ornemental qui est vendu par les pépiniéristes spécialisés (cf. "25.000 Plantes, où et comment les acheter" de la SNHF- Maison Rustique) où il est proposé sous 5 formes différentes :
Note complémentaire :
Il y a une monographie dans le traité de CAZIN (1876) mais c'est trop ancien. Ce qui semble caractériser cette Ericaceae est la présence d'huile essentielle riche en lédol (alcool terpénique) à l'origine de propriétés narcotiques. Il existe plusieurs synonymies: romarin sauvage, romarin de Bohême, thé du Labrador, lède. Il a été inscrit dans quelques anciennes pharmacopées et on lui reconnaît des propriétés contre la dysenterie, la bronchite; c'est également un tonique, un stomachique. De tels usages paraissent désuets et plusieurs ouvrages plus récents signalent surtout sa toxicité c'est à dire celle de l'huile essentielle (lédol).
Bref, pas grand chose concernant la matière médicale (ou très ancien) ; des choses pouvant être signalées concernant la toxicité in :
La synthèse qui a été réalisée est loin d'être exhaustive et repose uniquement sur les données bibliographiques que les téla-botanistes ont glanées. La notion de toxicité du Lédol n'avait pas été bien mise en évidence et il est donc indispensable de mettre en garde les éventuels utilisateurs de l'huile essentielle dans le traitement des maladies précitées.
Une bibliographie, trouvée sur Internet et compilée par Fabien ZUNINO peut être consultée ici.
1- Recherche effectuée sur Science Direct (Elsevier)
Elsevier est accessible sur www.elsevier.com.
"Plant responses to species removal and experimental warming in Alaskan tussock tundra."
par Hobbie S.E., Shevtsova A., Chapin III F.S.
S.E. Hobbie, Dept of Ecology, Evolution/Behavior, Univ. of Minnesota, 100 Ecology Bldg, 1987 Upper Buford Circle, St. Paul, MN 55108, USA; e-mail shobbie@tc.umn.edu
Résumé : We manipulated air temperature and the presence of the seven dominant plant species in Alaskan tussock tundra and measured shoot growth, branching, aboveground biomass, and reproduction of the remaining plant species. Warming stimulated shoot growth of the dominant sedges and shrubs after one and two years of manipulation and total leaf biomass of the dominant shrubs after three years. Warming decreased aboveground biomass of Eriophorum vaginatum, Cassiope tetragona and most non-vascular species. Warming also reduced total reproductive output of two of three species measured. Removal of single species had no effect on shoot growth of the remaining species. However, total aboveground biomass and reproduction of Ledum palustre encreased with removal of other shrub species, suggesting that competition limits biomass accumulation in L. palustre. Sphagnum removal increased the aboveground biomass of Betula nana. The higher frequency of significant warming versus species removal effects on plant growth and biomass suggests that direct limitation by environmental conditions is more important than limitation by species interactions in tussock tundra. Furthermore, we found no significant interactions between warming and species removal, suggesting that increased temperature per se will not alter the intensity of species interactions. When combined with knowledge of dispersal abilities and controls over establishment, extrapolation of species responses to environmental manipulation may thus allow us to predict effects of climate change on community composition. [Journal Article ; 74 Refs ; In English ; Summary in English].
Oikos
Volume 84, Issue 3
1999
Pages 417-434
S. Suzuki, Environmental Earth Sci, Hokkaido Univ, Sapporo 060, Japan
Résumé : In order to assess the responses of circumpolar and semicircumpolar plants growing around their southern distribution margins to artificial warming, we set up 11 open-top chambers (OTCs) on a fell-field (1680 m s.a.l) in the Taisetsu Mountains, northern Japan. The OTCs increased mean air temperature by 1.3°C through the growing season (June-September) and extended the length of the growing season. We examined phenology and leaf traits of plants in the OTCs and control plots during the first season under artificial warming treatment using two deciduous and three evergreen species. Ledum palustre (evergreen shrub), Vaccinium uliginosum, and Arctous alpinus (deciduous shrubs) showed earlier leaf emergence and/or flowering in the OTCs. Deciduous shrubs had longer individual leaf longevity and an extended foliage period in the OTCs than in the control plots. There were no significant differences in specific leaf area and leaf size for many species between the OTCs and the control plots. Vaccinium vitis-idaea (evergreen shrub), L. palustre, A. alpinus, and Empetrum nigrum (evergreen shrub) had lower leaf nitrogen concentration in the OTCs than in the control plots, whereas it was higher in V.uliginosum. Only E. nigrum showed larger annual shoot growth in the OTCs. No clear differences in response to the warming effect were detected between evergreen and deciduous species in the first season. Circumpolar plants growing in temperate alpine regions may be more affected by season length rather than temperature itself. [Journal Article; In English]
Global Change Biology
Volume 3 Supplement 1
1997
Pages 108-115
Medical and Scientific Department, VSM Geneesmiddelen BV, P.O. Box 9321, 1800 GH Alkmaar, Netherlands
Résumé : Objective : This study was conducted to examine the efficacy of Prrrikweg(TM) gel, a homeopathic after-bite gel, in relieving the effects of mosquito bites, in particular itching and erythema. Design: A double-blind, randomized, placebo-controlled clinical trial. Setting: London School of Hygiene and Tropical Medicine. Subjects: 100 healthy volunteers. Methods: All subjects were bitten under laboratory conditions by Aedes aegypti mosquitoes at one spot on the ventral aspect of the left forearm and another on a corresponding position on the right forearm. One spot was treated with the homeopathic after-bite gel and the other with a placebo gel. Main outcome measures: Itching was assessed on a 5-point discrete rating scale at 0, 0.5, 1, 26.5 and 48 h post-bite to compare the itch-relieving efficacy of the two treatments. Erythema development was assessed by photographing the bite sites, measuring length and width of the erythema with a calliper, and comparing the ratio of the erythema surface at baseline (T0) to the mean erythema surface at 0.5, 1, 26.5 and 48 h post-bite (T(mean)) for the two treatments. Results: Testing erythema development by comparing the ratio T0/T(mean, after-bite gel) and the ratio T0/T(mean, placebo gel) gave a two-tailed p = 0.098 (95% CI, -0.031-0.361) in favour of the after-bite gel. There was not a statistically significant difference between the itch relief provided by the two treatments (two-tailed p = 0.424; 95% CI, -0.541-0.191). The correlation between itching and erythema was significant (r = 0.46; p < 0.001). Conclusions: There are strong indications that the homeopathic after-bite gel reduces erythema development following mosquito bites. The homeopathic mother tinctures of Echinacea angustifolia DC., Ledum palustre L., Urtica urens L. as well as the Hamamelis extract in this gel, whether alone or in combination, are the biologically active ingredients. The homeopathic after-bite gel was not demonstrated to relieve itching; however, based on the correlation between erythema and itching, an effect on itching is not inconceivable.
Author Keywords : Aedes aegypti; clinical trials; Echinacea angustifolia; erythema; homeopathy; insect bites and stings Ledum palustre; pruritus; Urtica urens L.
Index Terms : insect sting; homeopathy; homeopathic agent
a- Institute of Plant Protection, Estonian Agricultural University, Riia 12 EE2400 Tartu Estonia
b- Institute of Zoology and Botany of the Estonian Academy of Sciences, Vanemuise 21 EE2400 Tartu Estonia
Received 17 June 1994; accepted 26 July 1994. Available online 4 February 2000.
Résumé : Insect growth regulating (IGR) and toxic effects evoked by Ledum palustre extracts on the metamorphosis stages of Tenebrio molitor were studied using differential thermocouple calorimeters. The timing of normal and failed ecdysis as well as the length of interecdysial periods were measured exactly from calorimetric recordings. Respiratory and muscular responses of poisoned insects were also reflected by characteristic patterns on the recordings.
Author Keywords: Calorimetry; Ecdysis; Ledum; Metabolism; Pupa; Tenebrio
* Corresponding author.
Thermochimica Acta
Volume 251
1 March 1995
Pages 247-253
Department of Genetics, University of Uppsala, Uppsala Genetic Center, Box 7003,S-750 07 Uppsala, Sweden
Index Terms : karyotype; chromosome number
Hereditas
Volume 122, Issue 2
1995
Pages 181-184
2- Recherche effectuée sur PUBMED
PUBMED est accessible sur www.nlm.nih.gov/databases/freemedl.html.
Bol'shakova IV, Lozovskaia EL, Sapezhinskii II.
[Antioxidant properties of plant extracts].
Biofizika. 1998 Mar-Apr;43(2):186-8. Russian.
PMID: 9591094; UI: 98253319
Hill N, Stam C, van Haselen RA.
The efficacy of Prrrikweg gel in the treatment of insect bites : a double-blind, placebo-controlled clinical trial.
Pharm World Sci. 1996 Jan;18(1):35-41.
PMID: 8861830; UI: 97014997
Narimanov AA.
[The antiradiation effectiveness of a mixture of Archangelica officinalis and Ledum palustre extracts in the fractionated gamma irradiation of mice].
Radiobiologiia. 1993 Mar-Apr;33(2):280-4. Russian.
PMID: 8502748; UI: 93275983
Narimanov AA.
[The reproductive capacity of male mice protected against the superlethal action of gamma radiation by the administration of a mixture of Archangelica officinalis and Ledum palustre extracts].
Radiobiologiia. 1992 Mar-Apr;32(2):271-5. Russian.
PMID: 1598402; UI: 92285443
Narimanov AA, Miakisheva SN, Kuznetsova SM.
[The radioprotective effect of extracts of Archangelica officinalis Hoffm. and Ledum palustre L. on mice].
Radiobiologiia. 1991 May-Jun;31(3):391-3. Russian.
PMID: 1887008; UI: 91360770
Fokina GI, Frolova TV, Roikhel' VM, Pogodina VV.
[Experimental phytotherapy of tick-borne encephalitis].
Vopr Virusol. 1991 Jan-Feb;36(1):18-21. Russian.
PMID: 1858353; UI: 91313916
Williams EG, Knox RB, Kaul V, Rouse JL.
Post-pollination callose development in ovules of Rhododendron and Ledum (Ericaceae) : zygote special wall.
J Cell Sci. 1984 Jul;69:127-35.
PMID: 6490744; UI: 85030655
Golebiowska J, Pedziwilk Z.
Soil microflora of the rhizosphere of plants from several habitats in the botanical garden in Poznan.
Acta Microbiol Pol B. 1975;7(4):211-7.
PMID: 5857; UI: 76202615
Schantz M von, Widen KG, Hiltunen R.
Structures of some aliphatic monoterpenoids isolated from the essential oil of Ledum palustre L.
Acta Chem Scand. 1973;27(2):551-5. No abstract available.
PMID: 4702590; UI: 73172959
Synthèse réalisée par : Guy-Georges GUITTONNEAU
Date de la synthèse : 27 novembre 2000
Ont contribués à cette synthèse :
Vincent BLONDEL
Fabien ZUNINO
Synthèse réalisée à partir des discussions de la liste tela-botanicae.
© Tela Botanica / 2000-2010 - Le réseau des Botanistes Francophones