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1.
J Ethnobiol Ethnomed ; 19(1): 44, 2023 Oct 18.
Article in English | MEDLINE | ID: mdl-37853377

ABSTRACT

BACKGROUND: Traditional Polynesian medicine for children has been poorly documented, and few data are available on their efficacy and safety. In this context, the aim of this study was to identify traditional practices used for treating children and then assess the efficacy and safety of the most cited remedies by reviewing the literature. METHODS: In 2022, a semi-structured survey was carried out on five islands from the Society archipelago (Bora Bora, Huahine, Moorea, Raiatea, and Tahiti). A total of 86 participants were interviewed including 19 experts in herbalism. A thorough literature review was performed on the most cited plant species to gather the relevant ethnobotanical, pharmacological, and clinical data of each remedy. RESULTS: Participants mentioned using 469 remedies to treat 69 health disorders. The most represented health categories were digestive system, skin disorders, infectious diseases, and respiratory system. A total of 67 plant species (representing 731 use-reports) were mentioned and Annona muricata, Gardenia taitensis, and Hibiscus rosa-sinensis were the main plants reported. Regarding the safety of cited remedies, one plant (Microsorum grossum) showed high risk of toxicity, and its use should be avoided in infants and children. CONCLUSION: Our survey confirms the importance of traditional medical practices for children in the Society Islands. A lack of data in children for most cited remedies demonstrate the need for more pharmacological and toxicological research on Polynesian medicinal plants. Finally, the potential risk of toxicity for some cited plant species reported calls for a better information of traditional medicine users and healers.


Subject(s)
Phytotherapy , Plants, Medicinal , Humans , Child , Ethnobotany , Medicine, Traditional , Polynesia , Health Knowledge, Attitudes, Practice
2.
Life (Basel) ; 12(5)2022 May 14.
Article in English | MEDLINE | ID: mdl-35629400

ABSTRACT

A preliminary ethnopharmacological survey, achieved in French Polynesia, led to the collection of the most cited plants among 63 species used to treat "infectious" diseases, with a description of their medicinal uses. Bibliographical investigations and antimicrobial screening permitted the selection of the botanical species Syzygium malaccense (Myrtaceae) for phytochemical analysis. Leaves of Syzygium malaccense were usually used in mixture with rhizomes of Curcuma longa to treat infectious diseases such as cystitis. The methanolic plant extracts were tested in vitro with an agar microdilution method on 33 bacteria strains and 1 yeast to obtain their Minimal Inhibitory Concentration (MIC), and cytotoxicity against HepG2 cells were evaluated. Antimicrobial synergistic effects of methanolic plant extracts from leaves of Syzygium malaccense and rhizomes from Curcuma longa were also evaluated. The bio-guided isolation of leaf extract from Syzygium malaccense led to the identification of seven alkyl-salicylic acids (anacardic acids or ginkgolic acids C15:0, C15:1, C17:0, C17:1, C17:2, C17:3 and C19:1) described for the first time in this species. All compounds were tested against Staphylococcus aureus (18.75 < MIC < 75.0 µg/mL), Streptococcus pyogenes (2.34 < MIC < 18.75 µg/mL) and Pseudomonas aeruginosa (MIC = 150 µg/mL), and their structure−activity relationships were discussed. The methanolic extract and salicylic derivatives from S. malaccense showed an interesting antimicrobial activity against Gram+ bacteria, without toxicity on hepG2 cells at 400 µg/mL. Moreover, these antibacterial compounds have already been studied for their anti-inflammatory activity, which supports the therapeutic interest of S. malaccense against infectious diseases.

3.
J Ethnopharmacol ; 292: 115186, 2022 Jun 28.
Article in English | MEDLINE | ID: mdl-35292376

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, many pathologies common or endemic to the territory cause diarrhea. This is the case for rotavirus gastroenteritis, salmonella food poisoning, ingestion of water contaminated by bacteria, and ciguatera. To treat these ailments, the population may employ traditional medicine for cultural reasons, geographical isolation, and poor health coverage. Polynesian remedies are often used without medical consultation and there is no data on their benefit-risk balance. A few ethnobotanical studies have been carried out in order to identify the traditional remedies used for various ailments, but few studies have focused on gastrointestinal pathologies. In this context, an ethnobotanical survey was carried out to identify treatments used for diarrhea and ciguatera, inventory the plants used, better understand the local representation of these remedies, and provide efficacy and safety data on these uses. MATERIALS AND METHODS: From February to April 2021, a semi-structured survey was conducted on six islands in French Polynesia, including one island in the Windward Islands archipelago (Tahiti), three islands in the Marquesas archipelago (Hiva Oa, Nuku Hiva, Tahuata), and two islands in the Leeward Islands archipelago (Raiatea, Tahaa). A total of 133 people was interviewed including 34 specialists (of which 29 experts in herbalism). RESULTS: These people mentioned the use of 27 plants for the treatment of diarrhea, and 24 for the treatment of ciguatera. Citrus aurantiifolia, Psidium guajava and Cordyline fruticosa were the three most cited plant species used for treating diarrhea, while Cocos nucifera, Punica granatum and Barringtonia asiatica were the most cited for ciguatera. A large majority of plants are widespread and introduced plants, which is congruent with the history of Polynesian people. While some plants are well known for similar uses (e.g. Psidium guajava for diarrhea, Heliotropium arboreum for ciguatera), others are less well known and may present toxicity risks (e.g. Barringtonia asiatica for ciguatera). CONCLUSION: Traditional Polynesian medicine is an integral part of the local culture so important to be preserved and valued. However, more pharmacological and toxicological studies are still needed to determine the benefit-risk balance of some of these remedies and to allow their official integration into the Polynesian health system.


Subject(s)
Ciguatera Poisoning , Ciguatera Poisoning/epidemiology , Diarrhea/drug therapy , Ethnobotany , Humans , Islands , Medicine, Traditional , Plants , Polynesia
4.
Molecules ; 25(19)2020 Sep 23.
Article in English | MEDLINE | ID: mdl-32977422

ABSTRACT

Hair loss is becoming increasingly prevalent as dietary and living habits change. The search for natural products to limit hair loss has led to tapping into traditional cosmetic knowledge. We studied three plants of the Polynesian cosmetopoeia, Bidens pilosa, Calophyllum inophyllum and Fagraea berteroana, to determine their ability to promote hair growth. Their chemical content was characterized by liquid chromatography coupled to mass spectrometry (LC-MS). Their proliferative activity on dermal papilla cells (DPCs) was assessed via MTT assay and molecular targets were evaluated by RT-qPCR analysis of seven factors involved in the modulation of the hair cycle, CCND1, LEF1, DKK1, WNT5A PPARD, TGFΒ1, PPARD and RSPO2. Our results show that our extracts significantly increased proliferation of dermal papilla cells. Furthermore, LC-MS/MS analysis revealed a diversity of molecules, flavonoids, iridoids and organic acids, some known for hair-inducing properties. Finally, specific extracts and fractions of all three plants either upregulated CCND1, LEF1 and PPARD involved in stimulating hair follicle proliferation and/or lowered the gene expression levels of hair growth inhibiting factors, DKK1 and TGFB1. Our findings suggest that extracts from B. pilosa, C. inophyllum and F. berteroana are interesting candidates to stimulate hair growth.


Subject(s)
Dermis/cytology , Dermis/drug effects , Hair Follicle/drug effects , Hair Follicle/growth & development , Plant Extracts/pharmacology , Tracheophyta/chemistry , Cell Line , Cell Proliferation/drug effects , Hair Follicle/cytology , Humans , Wnt Signaling Pathway/drug effects
5.
Nat Prod Res ; 34(19): 2847-2851, 2020 Oct.
Article in English | MEDLINE | ID: mdl-30938167

ABSTRACT

The glucosinolate (GL) profiles in leaf and stem of Rorippa sarmentosa (G.Forst. ex DC.) J.F.Macbr., Lepidium bidentatum Montin var. bidentatum, and Capparis spinosa subsp. cordifolia (Lam.) Fici indigenous to French Polynesia were investigated for the first time using LC-MS analysis. In the present study, we have established the presence of 8 known GLs in R. sarmentosa: 4-(methylsulfinyl)butyl- (1), but-3-enyl- (2), 5-(methylsulfinyl)pentyl- (3), 6-(methylsulfinyl)hexyl- (4), indol-3-ylmethyl- (6), 2-phenylethyl- (7), 8-(methylsulfinyl)octyl- (8), and 9-(methylsulfinyl)nonyl- (9) GLs. We have also tentatively identified for the first time the presence in R. sarmentosa of 7-(methylsulfinyl)heptyl GL (5). In addition, we have identified two known GLs in L. bidentatum var. bidentatum: benzyl- (10) and 4-methoxybenzyl- (11) GLs. Finally, the known methyl GL (12) was shown to be largely predominant in C. spinosa subsp. cordifolia.


Subject(s)
Glucosinolates/analysis , Magnoliopsida/chemistry , Capparis/chemistry , Chromatography, Liquid , Glucosinolates/chemistry , Mass Spectrometry , Molecular Structure , Plant Leaves/chemistry , Plant Stems/chemistry , Polynesia
6.
J Ethnopharmacol ; 245: 112159, 2019 Dec 05.
Article in English | MEDLINE | ID: mdl-31419502

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: In French Polynesia, embellishment of the hair and skin is an important cultural and everyday practice. Yet, little research has focused on traditional preparations used for beautification in this region and their potential development as innovative cosmetic ingredients. AIM OF THE STUDY: In this present study we aim to assess and compile the ethnocosmetic potential of plants of French Polynesia to select and further study plants showing the most promise to be developed as anti-aging, anti-blemish and hair care products. MATERIALS AND METHODS: A literature analysis of plants of the IECIC list, present in French Polynesia was conducted. The most interesting plants from a cosmetic development standpoint were selected based on four main criteria, i.e. their traditional use in Polynesian cosmetic-related preparations, their biogeographical status, their phytochemistry of cosmetic interest, and lastly their availability and absence from the UICN list. Furthermore, a preliminary screening of antioxidant and anti-inflammatory activities was also performed on several extracts obtained. RESULTS: Eleven plants were chosen, and a compilation of multidisciplinary data emphasized each selected plant's potentiality. Traditional allegations showed uses ranging from dermatology such as wound healing or anti-inflammatory properties, to hair growth promoting preparations or even skin ligthening ones. Preliminary screenings were useful in narrowing the number of extracts to study. Literature-based data associated to traditional uses depicted how the remaining plants and plant parts could be developed for targeted cosmetic applications. CONCLUSIONS: A prospective approach of plants used traditionally for cosmetic purposes in French Polynesia gave insight on their development potential when paired with the appropriate multidisciplinary data. The eleven plants presented show promise in being developed sustainably as natural anti-aging or hair care products and as skin brightening agents.


Subject(s)
Cosmetics , Plant Preparations/therapeutic use , Plants, Medicinal , Aging/drug effects , Animals , Hair/drug effects , Hair/growth & development , Humans , Polynesia , Skin Lightening Preparations/therapeutic use
7.
PhytoKeys ; 128: 73-84, 2019.
Article in English | MEDLINE | ID: mdl-31404396

ABSTRACT

When dealing with the taxonomy of Pacific coastal species within the region of New Caledonia and Vanuatu, one should examine all names published in Australasia and other Pacific islands. When the putative new species is also closely related to a highly praised ornamental species with many cultigens and with many old horticultural names, the task becomes more arduous. This is the case for the new species we describe as Pseuderanthemum melanesicum Gâteblé, Ramon & Butaud, which is closely related to the now pantropical cultivated species P. carruthersii (Seem.) Guillaumin s.l. Compared to P. carruthersii, P. melanesicum has carnose and shiny leaves, pedicels and sepals covered with glandular hairs, a short and enlarged corolla tube and can produce fertile capsules. The new species is a coastal taxon occurring naturally in the Melanesian archipelagos of New Caledonia and Vanuatu. This species seems uncommon in the Loyalty Islands but more common in the archipelago of Vanuatu and we propose it as Critically Endangered in New Caledonia, Vulnerable in Vanuatu and Least Concern when the IUCN evaluation is done globally.

8.
Ecol Evol ; 8(23): 12208-12220, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30598812

ABSTRACT

AIM: The final island ontogeny of the general dynamic model (GDM) (i.e., before island submergence) in tropical oceans corresponds to the coral atoll stage. Here, we examined whether the species richness of native vascular plants (indigenous and endemic species) on atolls is controlled by spatial and/or physical processes. We also predicted that atolls strongly affected by anthropogenic disturbance would have lower native species richness than predicted by spatial and physical processes. LOCATION: Marshall Islands, Kiribati Islands, Nauru, Niue, Johnston, Cook Islands, French Polynesia and Pitcairn Islands (Pacific Ocean). TAXON: Native vascular plants. METHODS: We used stepwise regression to test the relative influence of five biogeographic variables on native species richness. Relationships were assessed for the full set of 111 Pacific coral atolls, as well as for atoll subsets ranging from 9 to 45 atolls. An index of human impact was then estimated, and residuals in the regression model predicting species richness from biogeographic variables were compared with the level of human impact. RESULTS: A regression model including atoll area, highest atoll elevation, the stepping stone distances from the nearest raised atoll and volcanic island explained native species richness on the 111 Pacific coral atolls. Regression models for different archipelagos and atoll subsets were also significant. Endemic species richness was significantly linked with highest atoll elevation and the stepping stone distances from the nearest raised atoll. Residuals in the biogeographic regression model were barely related to human impact across the 111 atolls but were significantly related to human impact in the Kiribati atolls. MAIN CONCLUSIONS: Native species richness on atolls is mainly controlled by physical and spatial characteristics. However, anthropogenic disturbances have altered the predicted pattern of native species richness leading to a lower model fit in some atoll subsets.

9.
J Ethnobiol Ethnomed ; 12(1): 55, 2016 Nov 29.
Article in English | MEDLINE | ID: mdl-27899137

ABSTRACT

BACKGROUND: Cosmetic plants and their uses have often been neglected in ethnobotanical surveys which focus mainly on plants with medicinal or food uses. Thus, this survey was carried out to specifically investigate cosmetics in a small community and to establish a cosmetopoeia, based on the model of pharmacopoeia for medicinal plants. The geographic spread of the survey covered the Marquesas Islands, one of the five archipelagos of French Polynesia (Pacific Ocean). This archipelago was also recently investigated for its pharmacopoeia. METHODS: This survey is based on individual interviews of Marquesan informants on the islands of Tahiti (Society archipelago) and Nuku Hiva (Marquesas archipelago). The methodological approach was semi-directive with open-ended questions based on cosmetic criteria (application area, cosmetic use, plant). Before each interview, researchers and the informant signed a Prior Informed Consent (PIC). Quantitative analyses were performed using basic statistics and the indice of Fidelity Level (FL). RESULTS: Twenty-eight informants from five of the six inhabited Marquesan islands were interviewed and yielded more than 500 cosmetic recipes. Marquesan cosmetopoeia included 79 plant taxa, of which 5% are Marquesan endemics, 23% are indigenous, 28% are Polynesian introductions and 44% are modern introductions. Among the introduced species, half were cultivated whereas the other half were weedy species. Most of the plants were abundant and only eight species were considered rare, of which four were Marquesan endemics. Main cosmetic plants were identified through informant citations and fidelity levels, and included Calophyllum inophyllum, Cananga odorata, Citrus aurantiifolia, Cocos nucifera, Curcuma longa, Gardenia taitensis, Mentha spp., Ocimum basilicum, Rauvolfia nukuhivensis and Santalum insulare var. marchionense. The most referred application areas were skin, hair and private parts whereas the main cosmetic uses were perfume, hydration, medicinal care and healing. CONCLUSIONS: Through this survey, Marquesan cosmetopoeia was investigated in detail and uncovered a majority of introduced and abundant plants, and a minority of endemic and rare plants which required proper management to avoid future shortage. The well known perfumed coconut oil or monoi appeared as the main Marquesan cosmetic preparation either for the skin and the hair. Several plants and preparations warrant scientific investigations for their originality.


Subject(s)
Cosmetics , Ethnobotany , Plants , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Polynesia
10.
Planta Med ; 82(11-12): 961-6, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27280931

ABSTRACT

Oil from the nuts of Calophyllum inophyllum, locally called "Tamanu oil" in French Polynesia, was traditionally used for wound healing and to cure various skin problems and ailments. The skin-active effect of "Tamanu oil emulsion" was investigated on human skin cells (keratinocytes and dermal fibroblasts) and showed cell proliferation, glycosaminoglycan and collagen production, and wound healing activity. Transcriptomic analysis of the treated cells revealed gene expression modulation including genes involved in the metabolic process implied in O-glycan biosynthesis, cell adhesion, and cell proliferation. The presence of neoflavonoids as bioactive constituents in Tamanu oil emulsion may contribute to these biological activities. Altogether, consistent data related to targeted histological and cellular functions brought new highlights on the mechanisms involved in these biological processes induced by Tamanu oil effects in skin cells.


Subject(s)
Calophyllum/chemistry , Plant Extracts/pharmacology , Plant Oils/pharmacology , Skin/drug effects , Cell Division/drug effects , Cell Line, Transformed , Collagen/biosynthesis , Glycosaminoglycans/metabolism , Keratinocytes/drug effects , Skin/cytology , Wound Healing/drug effects
11.
PhytoKeys ; (56): 111-26, 2015.
Article in English | MEDLINE | ID: mdl-26491390

ABSTRACT

Sandalwoods encompass 19 species restricted to southeast Asia and the Pacific. The species Santalum austrocaledonicum Vieill. (Santalaceae) is endemic to New Caledonia (Grande-Terre, Isle of Pines, Loyalty Islands) and Vanuatu, where several varieties are recognized. The Loyalty Islands sandalwood variety is here reinstated as Santalum austrocaledonicum var. glabrum Hürl. emend. Butaud & P.Firmenich, mut. char. It was previously considered a synonym of the type variety; however, new morphological and genetic studies confirmed its distinctiveness. The key for New Caledonian varieties of Santalum austrocaledonicum has been updated and a short description of its essential oil composition and organoleptic quality is given.

12.
PhytoKeys ; (55): 119-27, 2015.
Article in English | MEDLINE | ID: mdl-26312047

ABSTRACT

A new species of Stigmaphyllon (Malpighiaceae) is described: Stigmaphyllonpatricianum-firmenichianum Butaud. It is restricted to the coral islands of Ouvéa, Lifou and Maré in the Loyalty Islands Province (New Caledonia) and is most similar to Stigmaphyllondiscolor (Gand.) C.E.Anderson, known from New Caledonia and Solomon Islands. Previously, plants now known as Stigmaphyllonpatricianum-firmenichianum were included in Stigmaphyllontaomense (Baker f.) C.E.Anderson, endemic to the northern part of Grande-Terre and Belep Islands (New Caledonia). A new circumscription of Stigmaphyllontaomense is proposed. The regional key for New Caledonian species of Stigmaphyllon is updated.

13.
J Ethnopharmacol ; 161: 200-13, 2015 Feb 23.
Article in English | MEDLINE | ID: mdl-25527315

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: This manuscript reports data on medicinal plants used in Marquesas Islands traditional medicine. The subject is interesting due to the extreme geographical isolation of this archipelago and the scarcity of data on this subject. The hypothesis of the authors was that traditional knowledge in this area should be consequently largely preserved. The usual ethnobotanical collection of use/symptom was completed by an additional quantitative ethnobotany analysis providing two indices: the relative frequency of plant uses for a given affliction (RF) and the Informant Consensus Factor (ICF). MATERIALS AND METHODS: Our ethnopharmacological study was carried out between 2009 and 2012 in several parts of the archipelago by collecting the accurate names of the medicinal plants, their uses, the methods of preparation of the remedies and the associated traditional nosology. Two methods were applied: ex situ focus groups with scientists and local association partners, using fresh plant specimens, dried specimens, and photographs, guided by an outline of simple questions, and in situ semi-structured interviews of informants during walk in the woods or homegarden sampling. RESULTS: 96 plant species were pointed out as medicine for which we collected 1774 use reports; 77 of these species cited by more than 1 informant are listed with their frequency of use. Three species account for one-third of use reports: Cocos nucifera (coconut), Gardenia taitensis (tiare Tahiti) and Microsorum grossum. Native species (either indigenous or endemic) represent only one quarter of all used species. The Polynesian introductions (plants introduced during Polynesian migrations) represent 42% of the Marquesan medicinal plants. On the other hand, one-third are modern introductions, introduced, for most of them, less than 200 years ago. Diseases are analyzed according to Marquesan concepts. In the present study, a special attention was focused on the descriptions of the local diseases. Their translation in French was discussed and verified in focus groups involving both scientists and Marquesan language specialists from the "Académie des Marquises". 40 plant species showed a high frequency of citation for a given affliction (RF>20). Despite the complex nosology the ICF to Marquesan traditional illness categories showed generally high ICF values, suggesting their strong coherence. CONCLUSIONS: An overview of the Marquesan pharmacopoeia, linked with ethnomedicinal practices, is presented in this paper. Marquesan traditional medicine survived until now despite the culture shock faced by the Marquesan population switching to numerous introduced plants commonly found in their close environment and easily gathered. Marquesan herbal medicine appears to draw its inspiration from a common Polynesian root. However further investigations on Marquesan nosologies are necessary to appreciate the originality of the Marquesan pharmacopoeia. Finally, the crossing of ICF and RF indices shows that 36 species have at least one significant use (frequencies>20%) with high ICF value (>0.5). This suggests that some key phytochemical ingredients may be present in these plants which require further phytopharmacological studies to a better knowledge of their medicinal properties.


Subject(s)
Medicine, Traditional , Phytotherapy , Plants, Medicinal , Adult , Aged , Aged, 80 and over , Female , Health Knowledge, Attitudes, Practice , Humans , Male , Middle Aged , Polynesia , Surveys and Questionnaires
14.
PhytoKeys ; (4): 95-107, 2011.
Article in English | MEDLINE | ID: mdl-22171183

ABSTRACT

A reassessment of collections of Marquesan Apocynaceae assigned to the genera Neisosperma Raf., Ochrosia Juss., and Rauvolfia L. revealed that two nomenclatural changes are necessary: 1) transfer of Neisosperma brownii Fosberg & Sachet to the genus Ochrosia, as Ochrosia brownii (Fosberg & Sachet) Lorence & Butaud, comb. nov., and 2) transfer of Ochrosia nukuhivensis Fosberg & Sachet to Rauvolfia as Rauvolfia nukuhivensis (Fosberg & Sachet) Lorence & Butaud, comb. nov. As a result, two species each of Ochrosia and Rauvolfia are recognized from the Marquesas Islands, all endemic. Recent field work has yielded important new data on their distribution, habitat, and conservation status. It is recommended that all four species should be added the IUCN Red List at the Critically Endangered (CR) category.

15.
Anal Chim Acta ; 624(1): 147-53, 2008 Aug 22.
Article in English | MEDLINE | ID: mdl-18706320

ABSTRACT

Various pyranocoumarins, calophyllolide, inophyllums B, C, G(1), G(2) and P, from Calophyllum inophyllum (Clusiaceae) leaves of French Polynesia (Austral, Marquesas, Society and Tuamotu archipelagos) have been determined in 136 leaf extracts using a high pressure liquid chromatography-UV-diode array detection (HPLC-UV-DAD) technique. Results show a wide range in chemical composition within trees growing on eighteen islands. The use of multivariate statistical analyses (PCA) shows geographical distribution of inophyllums and indicate those rich in HIV-1 active (+)-inophyllums. Inophyllum B and P contents (0.0-39.0 and 0.0-21.8 mg kg(-1), respectively) confirm the chemodiversity of this species within the large area of French Polynesia. The study suggests the presence of interesting chemotypes which could be used as plant source for anti-HIV-1 drugs.


Subject(s)
Anti-HIV Agents/pharmacology , Calophyllum/chemistry , Coumarins/pharmacology , HIV-1/drug effects , Plant Extracts/pharmacology , Plant Leaves/chemistry , Anti-HIV Agents/chemistry , Chromatography, High Pressure Liquid/methods , Coumarins/chemistry , Multivariate Analysis , Plant Extracts/chemistry , Polynesia , Pyranocoumarins/chemistry , Pyranocoumarins/pharmacology , Ultraviolet Rays
16.
Ann Bot ; 98(5): 1061-72, 2006 Nov.
Article in English | MEDLINE | ID: mdl-16945947

ABSTRACT

BACKGROUND AND AIMS: The impact of evolutionary forces on insular systems is particularly exacerbated by the remoteness of islands, strong founder effects, small population size and the influence of biotic and abiotic factors. Patterns of molecular diversity were analysed in an island system with Santalum insulare, a sandalwood species endemic to eastern Polynesia. The aims were to evaluate clonality and to study the genetic diversity and structure of this species, in order to understand the evolutionary process and to define a conservation strategy. METHODS: Eight nuclear microsatellites were used to investigate clonality, genetic variation and structure of the French Polynesian sandalwood populations found on ten islands distributed over three archipelagos. KEY RESULTS: It was found that 58 % of the 384 trees analysed were clones. The real size of the populations is thus dramatically reduced, with sometimes only one genet producing ramets by root suckering. The diversity parameters were low for islands (n(A) = 1.5-5.0; H(E) = 0.28-0.49). No departure from Hardy-Weinberg proportion was observed except within Tahiti island, where a significant excess of homozygotes was noted in the highland population. Genetic structure was characterized by high levels of differentiation between archipelagos (27 % of the total variation) and islands (F(ST) = 0.50). The neighbour-joining tree did not discriminate the three archipelagos but separated the Society archipelago from the other two. CONCLUSIONS: This study shows that clonality is a frequent phenomenon in S. insulare. The genetic diversity within populations is lower than the values assessed in species distributed on the mainland, as a consequence of insularity. But this can also be explained by the overexploitation of sandalwood. The differentiation between archipelagos and islands within archipelagos is very high because of the limited gene flow due to oceanic barriers. Delineation of evolutionary significant units and principles for population management are proposed based on this molecular analysis.


Subject(s)
Biological Evolution , Santalum/genetics , DNA, Satellite/genetics , Genetic Variation
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