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See detailEtude de l’efficacité et de la tolérance d’une tisane à base de Artemisia annua L. (Asteraceae) cultivée au Bénin pour la prise en charge du paludisme simple
Zime-Diawara, Hermine; Sissinto-Savi de Tove, Yolande; Akogbeto, Oscar Eric et al

in International Journal of Biological and Chemical Sciences (2015), 9(2), 692-702

Artemisia annua L. est une plante annuelle, glabre, de la famille des Asteraceae et originaire de la Chine. Cette plante contient plusieurs sesquiterpènes dont l’artémisinine (0,01% à 1,4% du poids des ... [more ▼]

Artemisia annua L. est une plante annuelle, glabre, de la famille des Asteraceae et originaire de la Chine. Cette plante contient plusieurs sesquiterpènes dont l’artémisinine (0,01% à 1,4% du poids des feuilles sèches) et d’autres composés comme les flavonoïdes, les coumarines, les triterpènes, les stéroïdes, les composés phénoliques, les purines, les lipides et les composés aliphatiques. Cette plante a été acclimatée et cultivée au Bénin. Elle a ensuite été testée pour la prise en charge du paludisme simple par un essai clinique. La concentration en artémisinine de cette plante était d’environ 0,30%.Il ressort de notre étude que la tisane de Artemisia annua L. (Asteraceae) obtenue au Bénin a une capacité d’action sur Plasmodium falciparum avec un taux d’efficacité supérieur à 95%, taux retenu par l’OMS pour valider un traitement. [less ▲]

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See detailCharacteristics of cattle rearing, herd composition and manifestations of climate change in the municipality of Banikoara in Benin
KATE, Sabai; Houndonougbo, Pascal ULiege; TOUGAN, Ulbad et al

in Journal of Biodiversity and Environmental Sciences (JBES) (2015), 6(3), 146-157

The current study aims to assess the breeding system, the herd structure of the cattle farm and the climate changes in the municipality of Banikoara. It appears that the majority of farmers was from ... [more ▼]

The current study aims to assess the breeding system, the herd structure of the cattle farm and the climate changes in the municipality of Banikoara. It appears that the majority of farmers was from Fulani ethnic group, of 46 years old and married. Livestock farming was their main activity. The main crops produced included maize, sorghum, millet and cotton. The reared animal species were composed of cattle, goats, sheep, pigs, chickens and guinea fowl with the predominance of chicken (p <0.05) . The exploited cattle breeds were Borgou, Somba Zebu Peulh, Barougoudji, Bororo, Kiwali and Kétégui with a predominance of the cattle Borgou (p <0.001). The cattle breeding systems were of traditional type. The reported age at first calving varies between 2.5 and 4 years. The calving interval fluctuates between 8 and 13 months. The best daily milk production per cow was reported in the district of 5 (8.38 liters) and lowest yields was obtained in districts 1 (p <0.05). The longevity of the animals varied between 8 and 14 years. The selection criteria used in the choice of reproductive cattle by farmers were the coat color, format, health, size of limb and conformation of limbs. The climate change manifestations in the municipality of Banikoara were reported as frequent droughts, high winds, excessive heat, scarceness of rains and frequent floods, declines of pastoral productivity, overgrazing, reduction of water resources and crop residues and shrinking corridors. [less ▲]

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See detailHabitat Use by White-Thighed Colobus in the Kikélé Sacred Forest: Activity Budget, Feeding Ecology and Selection of Sleeping Trees
Djègo-Djossou, Sylvie; Koné, I; Fandohan, A.B. et al

in Primate Conservation (2015), 29

Abstract: Understanding habitat preference and use is an important aspect of primate ecology, and is essential for setting conservation strategies. This study examined the activity budget, feeding ecology ... [more ▼]

Abstract: Understanding habitat preference and use is an important aspect of primate ecology, and is essential for setting conservation strategies. This study examined the activity budget, feeding ecology and selection of sleeping trees of a population of white-thighed colobus (Colobus vellerosus). A group of 18 was followed during 72 days over a full annual cycle in the Kikélé Sacred Forest of the Bassila administrative region in central Benin (West Africa). Activity budget and diet were determined using scan sampling. The structure of the habitat and the physical characteristics of sleeping trees were determined using plot surveys. Resting, feeding, moving, social interactions and other activities accounted for 56.6%, 26.3%, 13.0%, 3.3%, and 0.7% of the activity budget, respectively. The group spent more time feeding and less time moving in the dry season compared to the rainy season. The diet was composed of 35 plant species belonging to 16 families, with items including leaves, fruits, seeds, buds, bark, flowers, gum, and inflorescences. Only three tree species were used as sleeping trees: Celtis integrifolia, Cola cordifolia, and Holoptelea grandis. Our findings suggest that the monkeys prefer tall (22.53 ± SD 3.76 m) and large-trunked (112.07 ± SD 14.23 cm) sleeping trees. The results of this study can be used for sound management of the white-thighed colobus in the study area and elsewhere. [less ▲]

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See detailLe genre Guibourtia Benn., un taxon à haute valeur commerciale et sociétale (synthèse bibliographique)
Tosso, Dji-ndé Félicien ULiege; Daïnou, Kasso ULiege; Hardy, J. Olivier et al

in Biotechnologie, Agronomie, Société et Environnement (2015), 19(1),

Known as a genus of great socio-cultural and economical importance, Guibourtia Benn. includes morphologically very similar multipurpose sister species, found in various habitats with different climate and ... [more ▼]

Known as a genus of great socio-cultural and economical importance, Guibourtia Benn. includes morphologically very similar multipurpose sister species, found in various habitats with different climate and soil conditions. In many places, Guibourtia is subject to local overexploitation by forest companies and local communities. As the population density of Guibourtia species is generally very low, it may be necessary to conduct scientific investigations that will provide valuable information for the management of the populations concerned. This paper is based on an extensive literature review and summarizes the available information on the genus Guibourtia, in terms of botany, ecology, genetics, forestry and ethnobotany. Our review provided evidence that, to date, ecological and silvicultural knowledge regarding Guibourtia species is lacking and that it is very difficult to morphologically differentiate very similar sister species. In addition, we provide a new determination key for the genus Guibourtia. Based on the available information, it is difficult to assess the conservation status of these taxa. Further investigations are needed to suggest appropriate management strategies for Guibourtia. Moreover, species diversity within this genus and its distribution in various tropical biomes make it an excellent biological model for understanding the historical, biological and environmental mechanisms that explain the diversity of tropical moist forests. [less ▲]

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See detailImportance des modèles de distribution de niche potentielle dans la gestion des espèces tropicales exploitées: cas des taxons du genre Guibourtia Benn
Tosso, Dji-ndé Félicien ULiege; Daïnou, Kasso ULiege; Hambuckers, Alain ULiege et al

Poster (2014, September 24)

De la famille des (Fabaceae / Caesalpinioideae) et composé de 13 espèces en Afrique, le genre Guibourtia comporte des taxons à forte valeur culturelle et à forte valeur commerciale. Aujourd'hui, la ... [more ▼]

De la famille des (Fabaceae / Caesalpinioideae) et composé de 13 espèces en Afrique, le genre Guibourtia comporte des taxons à forte valeur culturelle et à forte valeur commerciale. Aujourd'hui, la pression de l'exploitation combinée aux faibles densités de ce genre, fait a priori peser d’importantes menaces sur certaines de ses populations. Un projet de recherche a donc été initié afin de mieux comprendre la structure et la diversité génétique des populations de Guibourtia, en lien avec l'exploitation forestière et les patrons de reproduction spécifiques. Un premier volet de la recherche a consisté à identifier les déterminants climatiques expliquant la distribution des espèces. Nous avons combinée des modèles statiques (Maxent et régression logistique) avec des données du modèle climatique global CNRM CM5, et sur la base de l'occurrence de ces taxons entre 1950 et 2000. Il en ressort que les espèces du genre Guibourtia sont sensibles aux facteurs précipitation (69,2 %) et amplitude thermique (74,3 %). Dans un second temps, il sera utilisé les modèles climatiques des ères géologiques passées afin d'inférer la distribution de l'espèce au cours du Quaternaire, et de faire le lien avec des analyses phylogénétiques et phylogéographiques. Il sera également possible d'évaluer la distribution future de l'espèce tenant compte des modèles d'évolution du climat. Enfin, le projet de recherche s'attèlera particulièrement aux relations phylogénétiques entre espèces morphologiquement similaires en sympatrie ou parapatrie, en caractérisant en détail les flux de gènes entre individus de ces taxons proches, ainsi que leur degré de similarité physiologique. Les résultats de l’étude in fine contribueront à proposer des stratégies de conservation et de gestion durable dans le contexte de l’exploitation forestière d’Afrique centrale et du changement climatique en cours. [less ▲]

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See detailSpeciation slowing down in widespread and long-living tree taxa : insights from the tropical timber tree genus Milicia (Moraceae)
Daïnou, Kasso ULiege; Mahy, Grégory ULiege; Duminil, Jérôme et al

in Heredity (2014)

The long generation time and large effective size of widespread forest tree species can result in slow evolutionary rate and incomplete lineage sorting, complicating species delimitation. We addressed ... [more ▼]

The long generation time and large effective size of widespread forest tree species can result in slow evolutionary rate and incomplete lineage sorting, complicating species delimitation. We addressed this issue with the African timber tree genus Milicia that comprises two morphologically similar and often confounded species: M. excelsa, widespread from West to East Africa, and M. regia, endemic to West Africa. We combined information from nuclear microsatellites (nSSRs), nuclear and plastid DNA sequences, and morphological systematics to identify significant evolutionary units and infer their evolutionary and biogeographical history. We detected five geographically coherent genetic clusters using nSSRs and three levels of genetic differentiation. First, one West African cluster matched perfectly with the morphospecies M. regia that formed a monophyletic clade at both DNA sequences. Second, a West African M. excelsa cluster formed a monophyletic group at plastid DNA and was more related to M. regia than to Central African M. excelsa, but shared many haplotypes with the latter at nuclear DNA. Third, three Central African clusters appeared little differentiated and shared most of their haplotypes. Although gene tree paraphyly could suggest a single species in Milicia following the phylogenetic species concept, the existence of mutual haplotypic exclusivity and nonadmixed genetic clusters in the contact area of the two taxa indicate strong reproductive isolation and, thus, two species following the biological species concept. Molecular dating of the first divergence events showed that speciation in Milicia is ancient (Tertiary), indicating that long-living tree taxa exhibiting genetic speciation may remain similar morphologically. [less ▲]

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See detailDéforestation, savanisation et développement agricole des paysages de savanes-forêts dans la zone soudano-guinéenne du Bénin
Mama, Adi; Bamba, Issouf; Sinsin, Brice et al

in Bois et Forêts des Tropiques (2014), 322

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See detailChemical composition, cytotoxicity and in vitro antitrypanosomal and antiplasmodial activity of the essential oils of four Cymbopogon species from Benin.
Kpoviessi, Salome; Bero, Joanne; Agbani, Pierre et al

in Journal of Ethnopharmacology (2014), 151

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon species are largely used in folk medicine for the treatment of many diseases some of which related to parasitical diseases as fevers and headaches. As part of ... [more ▼]

ETHNOPHARMACOLOGICAL RELEVANCE: Cymbopogon species are largely used in folk medicine for the treatment of many diseases some of which related to parasitical diseases as fevers and headaches. As part of our research on antiparasitic essential oils from Beninese plants, we decided to evaluate the in vitro antiplasmodial and antitrypanosomal activities of essential oils of four Cymbopogon species used in traditional medicine as well as their cytotoxicity. MATERIALS AND METHODS: The essential oils of four Cymbopogon species Cymbopogon citratus (I), Cymbopogon giganteus (II), Cymbopogon nardus (III) and Cymbopogon schoenantus (IV) from Benin obtained by hydrodistillation were analysed by GC/MS and GC/FID and were tested in vitro against Trypanosoma brucei brucei and Plasmodium falciparum respectively for antitrypanosomal and antiplasmodial activities. Cytotoxicity was evaluated in vitro against Chinese Hamster Ovary (CHO) cells and the human non cancer fibroblast cell line (WI38) through MTT assay to evaluate the selectivity. RESULTS: All tested oils showed a strong antitrypanosomal activity with a good selectivity. Sample II was the most active against Trypanosoma brucei brucei and could be considered as a good candidate. It was less active against Plasmodium falciparum. Samples II, III and IV had low or no cytotoxicity, but the essential oil of Cymbopogon citraus (I), was toxic against CHO cells and moderately toxic against WI38 cells and needs further toxicological studies. Sample I (29 compounds) was characterised by the presence as main constituents of geranial, neral, beta-pinene and cis-geraniol; sample II (53 compounds) by the presence of trans-p-mentha-1(7),8-dien-2-ol, trans-carveol, trans-p-mentha-2,8-dienol, cis-p-mentha-2,8-dienol, cis-p-mentha-1(7),8-dien-2-ol, limonene, cis-carveol and cis-carvone; sample III (28 compounds) by beta-citronellal, nerol, beta-citronellol, elemol and limonene and sample IV (41 compounds) by piperitone, (+)-2-carene, limonene, elemol and beta-eudesmol. CONCLUSIONS: Our study shows that essential oils of Cymbopogon genus can be a good source of antitrypanosomal agents. This is the first report on the activity of these essential oils against Trypanosoma brucei brucei, Plasmodium falciparum and analysis of their cytotoxicity. [less ▲]

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See detailEffect of inventory plot patterns in the floristic analysis of tropical woodland and dense forest
Houeto, Georges; Glele Kakai, Romain L.; Salako, Valère et al

in African Journal of Ecology (2013), 51(3),

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See detailSpecies delimitation and diversification in the widespread tree genus Milicia (Moraceae)
Daïnou, Kasso ULiege; Mahy, Grégory ULiege; Duminil, Jérôme et al

Conference (2013, June)

The long generation time and large effective size of widespread forest tree species can result in slow evolutionary rate and incomplete lineage sorting, complicating species delimitation. We addressed ... [more ▼]

The long generation time and large effective size of widespread forest tree species can result in slow evolutionary rate and incomplete lineage sorting, complicating species delimitation. We addressed this issue with the African timber tree genus Milicia that comprises two morphologically similar and often confounded species: M. excelsa, widespread from West to East Africa, and M. regia, endemic to West Africa. We combined information from nuclear microsatellites (nSSRs), nuclear and plastid DNA sequences, and morphological systematics to identify significant evolutionary units and infer their evolutionary and biogeographical history. We detected five geographically coherent genetic clusters using nSSRs and three levels of genetic differentiation. First, one West African cluster matched perfectly with the morphospecies M. regia, which formed a monophyletic clade at both DNA sequences. Second, a West African M. excelsa cluster formed a monophyletic group at plastid DNA and was more related to M. regia than to Central African M. excelsa, but shared many haplotypes with the latter at nuclear DNA. Third, three Central African clusters appeared little differentiated and shared most of their haplotypes. Although gene tree paraphyly could suggest a single species in Milicia following the Phylogenetic Species Concept, the existence of mutual haplotypic exclusivity and non-admixed genetic clusters in the contact area of the two taxa indicate strong reproductive isolation, and thus, two species following the Biological Species Concept. Molecular dating of the first divergence events showed that speciation in Milicia is ancient (Tertiary), indicating that long-living tree taxa exhibiting genetic speciation may remain similar morphologically. [less ▲]

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See detailEffets de lisière sur la productivité du teck (Tectona grandis L.f.): étude de cas des teckeraies privées du Sud-Bénin
Toyi, Mireille Scholastique; Bastin, Jean-François ULiege; Andre, Marie ULiege et al

in Tropicultura (2013), 31(1), 71-77

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge ... [more ▼]

The present study aims to improve the production of teak wood (Tectona grandis L.f.) in private plantations in southern Benin through the application of a central concept in landscape ecology: the edge effect. As teak is an heliophilous species, the hypothesis of a higher wood production in edges was tested on the basis of the basal area. Sixty-two private teak plantations were investigated and 10,667 trees were measured. The stratified sampling scheme in three distinct parts for each plantation (the centre, the edge and the summits) permitted to highlight the edge effect on wood production. For each part, a plot was installed and the diameter at breast height (dbh) was measured for all trees. The leaf area between the edge and the centre of plantations was measured. Finally, the influence of the spatial configuration of plantations and the direction of each side of these plantations on the production of wood was tested. Results show that the edge effect on the production of teak wood affects four planting lines, the first presenting a production of 150% relative to the centre. We noticed a significant influence of the edge on the leaf area of about 218% relative to the centre. No influence of the direction of the sides of the plantation was observed. The shape of the plantations presents a significant influence on the wood production. These results permitted to propose a planting model included in an agroforestry system that optimizes the production of wood per area and having a succession of two planting lines interrupted by fields. [less ▲]

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See detailTree plantation will not compensate natural woody vegetation cover loss in the Atlantic department of Southern Benin
Toyi, Mireille Scholastique; Barima, Sabas; Mama, Adi et al

in Tropicultura (2013), 31(1), 62-70

This study deals with land use and land cover changes for a 33 years period. We assessed these changes for eight land cover classes in the south of Benin by using an integrated multi-temporal analysis ... [more ▼]

This study deals with land use and land cover changes for a 33 years period. We assessed these changes for eight land cover classes in the south of Benin by using an integrated multi-temporal analysis using three Landsat images (1972 Landsat MSS, 1986 Landsat TM and 2005 Landsat ETM+). Three scenarios for the future were simulated using a first-order Markovian model based on annual probability matrices. The contribution of tree plantations to compensate forest loss was assessed. The results show a strong loss of forest and savanna, mainly due to increased agricultural land. Natural woody vegetation (“forest”, “wooded savanna” and “tree and shrub savanna”) will seriously decrease by 2025 due to the expansion of agricultural activities and the increase of settlements. Tree plantations are expected to double by 2025, but they will not compensate for the loss of natural woody vegetation cover. Consequently, we assist to a continuing woody vegetation area decrease. Policies regarding reforestation and forest conservation must be initiated to reverse the currently projected tendencies. [less ▲]

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See detailInfluence de l'écartement et de la fertilisation azotée sur le rendement et la qualité des semences de Brachiaria ruziziensis en climat tropical sub-humide
Adjolohoun, Sébastien; Bindelle, Jérôme ULiege; Adandedjan, CLaude et al

in Fourrages (2013), 216

Influence of row spacing and nitrogen fertilizer on Brachiaria ruziziensis (Germain and Evrard) Crins seed production and quality in a tropical subhumid climate Row spacing and nitrogen fertilizer had ... [more ▼]

Influence of row spacing and nitrogen fertilizer on Brachiaria ruziziensis (Germain and Evrard) Crins seed production and quality in a tropical subhumid climate Row spacing and nitrogen fertilizer had influenced in various way seed yield and quality. A 3-year experiment was conducted on ferruginous soils of subhumid zone of West Africa to evaluate the influence of 3 row spacings (20, 40 and 80 cm) and 4 nitrogen levels (0, 50, 100 and 200 kg Nha-1) on Brachiaria ruziziensis (Germain and Evrard) Crins (commun type) seed production, quality and dry matter production. Rainfall recorded during experiment was between 1050 and 1210 mm/year. Plots were allocated in a completely randomised block design with 4 replications per treatment. The results show that seed yield, seed fertility, diaspore and caryopsis weight varied between 26 and 114 kgha-1, 45 and 93 %, 327 and 601 mg and 219 and 475 mg, respectively. Effects of row spacing and N levels were variable through years. During the first experiment year, 20 and 40 cm row width produced significantly (p < 0.01) more seed than 80 cm row spacing but there was no significant difference between 20 and 40 cm row spacings. In the two subsequent years, row spacing had not influence seed yield. For fertilizer, N level of 50 or 100 kgha-1 had produced significantly more seed than 0 or 200 kg Nha-1 during the first year but no significant difference had been observed between 50 and 100 kg Nha-1. In the second year, seed yield ranged in the order: F50 = F100 > F200 > F0 (p < 0.05). In the third year, the ranking was: F100 > F50 > F200 > F0 (p < 0.05). Row spacing had no influence on seed fertility and seed germination. N fertilizer had significantly influenced seed fertility, diaspore weight and germination but had no effect on caryopsis weight or germination rate. It can be concluded that spacing row of 40 cm would be recommended. N fertilizer input at the rate of 50 kgha-1 is necessary during the establishment year. In the second and third years, 50 and 100 kg of Nha-1 should be applied, respectively, for optimum seed yield and quality. [less ▲]

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See detailReproductive phenology stages and their contributions to seed production of two Arachis pintoi ecotypes (CIAT 17434 and CIAT 18744) in Sudanian savanna region of Benin, West Africa
Adjolohoun, Sebastien; Bindelle, Jérôme ULiege; Adandedjan, Claude et al

in Agricultural Science Research Journal (2013), 3(6), 152-157

Flowering pattern, reproductive stage period (flowering, peg production, pod production and seed maturation) and efficiency of each stage for mature fruit production of two Arachis pintoi ecotypes (CIAT ... [more ▼]

Flowering pattern, reproductive stage period (flowering, peg production, pod production and seed maturation) and efficiency of each stage for mature fruit production of two Arachis pintoi ecotypes (CIAT 17434 and CIAT 18744) were investigated in West Africa. Plants were sown in a randomized complete block design with four replicates per ecotype. Data collected over 3 years were analyzed with ANOVA. First flowers appeared on average 26 and 45 d after sowing for CIAT 17434 and CIAT 18744, respectively. Pegs began to extend about 8 and 18 d after anthesis; pod initiation about 22 and 40 d after anthesis and seed fully matured about 85 and 120 d after anthesis, respectively. CIAT 17434 produced (2269 flowers/plant) significantly (p≤0.05) more flower than CIAT 18744 (761 flowers/plant) during 7 months flowering. Conversely, flower efficiency for peg production was significantly (p≤0.05) higher for CIAT 18744 (8.14%) than for CIAT 17434 (4.02%). From 85 to 97% of pegs produced pods for both ecotypes. This research showed clearly that the principal constraint for effective seed production in particular ecological conditions of West Africa was the quite low efficiency of flowers for pegs production. [less ▲]

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See detailInfluence of cutting height on dry matter production and crude protein content of four Panicum maximum ecotypes in Benin (West Africa)
Adjolohoun, Sébastien; Bindelle, Jérôme ULiege; Adandédjan, Claude et al

Poster (2012, November 15)

A field study was conducted under rainfall conditions (1200 mm/year) to determine the effects of different cutting heights (5, 10, 15, 20 cm) on dry matter production and fodder quality of four Panicum ... [more ▼]

A field study was conducted under rainfall conditions (1200 mm/year) to determine the effects of different cutting heights (5, 10, 15, 20 cm) on dry matter production and fodder quality of four Panicum maximum local ecotypes (HHLLLW, MHMLLW, lHSLNL, lHLLLW) differing in their morphology. Ecotype MHMLLW appeared more suitable and the best management is to harvest at 15 cm height. It produced 6054 kg DMyear-1 containing 8.05% CP. [less ▲]

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See detailIdentité et écologie des espèces forestières commerciales d'Afrique Centrale: le cas de Milicia spp.
Daïnou, Kasso ULiege; Doucet, Jean-Louis ULiege; Sinsin, Brice et al

in Biotechnologie, Agronomie, Société et Environnement (2012), 16

Le terme iroko regroupe les deux espèces du genre africain Milicia et désigne le bois qui en est dérivé. Malgré une importance économique reconnue depuis plus de deux siècles et une diminution sensible ... [more ▼]

Le terme iroko regroupe les deux espèces du genre africain Milicia et désigne le bois qui en est dérivé. Malgré une importance économique reconnue depuis plus de deux siècles et une diminution sensible des densités de population du fait de l'exploitation, les connaissances scientifiques utiles à la gestion durable de l'iroko font défaut, particulièrement en Afrique Centrale. L'existence même d'une spéciation au sein du genre Milicia mérite d'être revérifiée: les caractères utilisés pour séparer les deux taxons M. excelsa (Welw.) C.C. Berg et M. regia (A. Chev.) C.C. Berg sont peu consistants et une révision de ces traits distinctifs permettrait de réétudier le niveau de vulnérabilité des populations de Milicia spp., et donc de revoir les stratégies de gestion de ce groupe taxonomique. M. regia n'a fait l'objet que de rares études écologiques tandis que M. excelsa, plus largement distribuée, a retenu l'attention scientifique en Afrique de l'Ouest, dans une certaine mesure. Dans tous les cas, les traits d'histoire de vie conditionnant la diversité génétique et le taux de régénération naturelle méritent d'être identifiés ou mieux décrits. En particulier, les connaissances existantes sur les populations reproductrices, les facteurs régulant la floraison, les patrons de fructification et de dispersion des diaspores, ainsi que d'autres caractères qui amènent à décrire l'iroko comme un arbre pionnier (besoins en lumière, dormance des graines) devraient être mieux documentés. Enfin, la dynamique même des populations naturelles de juvéniles devra également être mieux caractérisée. En l'absence de données fines en écologie, la durabilité de nombreuses ressources ligneuses commerciales est tributaire d'actions sylvicoles, lesquelles peuvent être coûteuses et ne pas être garanties sur le long terme. [less ▲]

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See detailBark recovery of 12 medicinal tree species from Benin after bark harvesting
Delvaux, Claire; Darchambeau, François ULiege; Sinsin, Brice et al

Conference (2009, March 27)

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See detailRecovery from bark harvesting of 12 medicinal tree species in Benin, West Africa
Delvaux, Claire; Sinsin, Brice; Darchambeau, François ULiege et al

in Journal of Applied Ecology (2009), 46(3), 703-712

The growing interest in medicinal plants from both international industry and local markets requires management of tree bark harvesting from natural forests in order to prevent inappropriate exploitation ... [more ▼]

The growing interest in medicinal plants from both international industry and local markets requires management of tree bark harvesting from natural forests in order to prevent inappropriate exploitation of target species. This study was designed to determine the bark re-growth response of a selected number of medicinal tree species as a basis for the development of an optimal bark harvesting method. In 2004, bark was harvested from 925 trees belonging to 12 species in 38 sites in a dry forest in Benin, West Africa. Two years later, the response of trees to bark harvesting was examined with respect to re-growth (edge or sheet), development of vegetative growth around the wound, and the sensitivity of the wound to insect attack. Two species, Khaya senegalensis and Lannea kerstingii, showed complete wound recovery by edge growth. At the other extreme, Afzelia africana, Burkea africana and Maranthes polyandra had very poor edge growth. M. polyandra showed good sheet growth, whereas the other 11 species had none or poor sheet growth after total bark harvesting. In contrast, partial bark removal allowed better sheet growth in all 12 species studied. Insect sensitivity was species-specific. Insect attacks were negatively correlated with non-recovered wound area, but there was a marked species effect for the same rate of regeneration. L. kerstingii and K. senegalensis had very good and similar re-growth, but L. kerstingii was very susceptible to insect attack, whereas K. senegalensis appeared to be very resistant. Only a few individuals developed vegetative growth, and each tree usually developed only one or two agony shoots, but there was no significant difference between species. Synthesis and applications. This is the first study to provide data on the ability of trees to close wounds after bark harvesting in West Africa. We report large variability in the response of different species to our bark harvesting technique, and identify just two out of the 12 study species as suitable for sustainable bark harvesting. Based on our results, we developed a decisional step method to help forest managers select the best techniques for managing medicinal tree species as an alternative to bark harvesting, for example, coppice management, harvesting leaves instead of bark, stand establishment, and collaboration with timber companies. [less ▲]

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See detailDiet and food preference of the waterbuck (Kobus ellipsiprymnus defassa) in the Pendjari National Park, Benin
Kassa, Barthélemy; Libois, Roland ULiege; Sinsin, Brice

in African Journal of Ecology (2008), 46(3), 303-310

This study investigated composition and selectivity in diet for waterbuck in the Pendjari National Park in northwestern Benin, through the use of micrographic analysis of faecal samples. Three plant ... [more ▼]

This study investigated composition and selectivity in diet for waterbuck in the Pendjari National Park in northwestern Benin, through the use of micrographic analysis of faecal samples. Three plant species (Panicum anabaptistum, Echinochloa stagnina and Andropogon gayanus) were regularly consumed all year round. Meanwhile, three other species (i.e., Hyparrhenia involucrata, Acroceras amplectens and Oryza barthii) are mostly found in its diet during the beginning of the rainy season. During the dry season, long life grasses (>40%) and tree forage (about 35%) were the most dominant life form in the diet. On the contrary at the beginning of the rainy season, annual species (> 50%) were dominant. In conclusion, the waterbuck has a grazer regime when plant species are abundant and a mixed diet during the dry season. Waterbuck’s food niche breath, defined by Hespenheide [Ecology and Evolution of communities. Harvard Univ. Press, 1975], was lower than 1, implying this antelope does not eat all food categories in a proportional way. Shannon diversity index showed that the diet was more diversified during the rainy season and less diversified at the end of the dry season. Based on [Ecology, 64 (1983), 1297] diet selectivity index, waterbuck exerted a positive selection on the major graminaceous species. [less ▲]

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