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Le problème de compétition entre les adventices et les cultures se trouve au coeur des préoccupations de la production agricole. La gestion durable des adventices nécessite une connaissance de la flore. Ainsi cette étude a été menée sur deux sites d’exploitation (gombo et tomate) afin de caractériser les adventices en fonction des amendements organiques utilisés dans le temps et d’évaluer les rendements des cultures associées. A cet effet des inventaires floristiques ont été réalisés tous les 15 jours dès la levée des plantules. Les points quadrants ont été utilisés. Ainsi 23 espèces, réparties en 23 genres appartenant à 14 familles, ont été rencontrées. La parcelle du gombo (23 espèces) est plus riche que celle de la tomate (12 espèces). Les indices de Shannon (H’) et de Pielou diffèrent d’une parcelle à l’autre. Leurs valeurs relativement faibles variant respectivement entre 0,78 et 0,58 pour H’ ; 0,401 et 0,371 pour E montrent que certaines espèces dominent au niveau des deux parcelles. L’indice de beta (0,68) montre qu’il existe une similarité entre ces deux parcelles même si 32% des espèces sont spécifiques à la parcelle du gombo. Les résultats obtenus montrent que Cyperus rotondus, Kyllinga squamulata, Digitaria horizontalis, Spermacoce radiata et Nelsonia canescens sont les espèces dominantes et sont plus fréquentes dans les traitements : terreaux de manguier à 2 kg (TM2) pour le gombo et terreaux de SONACOS à 1 kg et cendre de SONACOS à 0,1 kg (T1C0,1) et cendre de SONACOS à 0,1 kg (T0C0,1) pour la tomate. Cependant les rendements des cultures sont plus faibles dans ces traitements et sont plus élevés dans le traitement Ts2 où la fréquence des espèces est élevée. En définitive, la présence d’une forte adventice compétitrice est susceptible de générer des pertes de rendements. The problem of competition between weeds and crops has become a major concern in agricultural production. Sustainable weed management required knowledge of the flora. Thus, this study was carried out on two farming sites (gumbo and tomato) in order to identify weeds according to the organic amendments used and to evaluate the yields of the associated crops. For this purpose, floristic inventories were carried out every 15 days as soon as the seedlings emerged. Quadrat points were used. Thus 23 species, divided into 23 genera belonging to 14 families, were encountered. The gumbo plot (23 species) was richer than the tomato plot (12 species). The Shannon (H') and Pielou indices differed from one plot to another. Their relatively low values varying respectively between 0.78 and 0.58 for H'; 0.401 and 0.371 for E showed that some species dominate in both plots. The beta index (0.68) showed that there was a similarity between these two plots even if 32% of the species were specific to the okra plot. The results obtained showed that Cyperus rotondus, Kyllinga squamulata, Digitaria horizontalis, Spermacoce radiata and Nelsonia canescens were the dominant species and were more frequent in the treatments: 2 kg mango potting soil (TM2) for okra and 1 kg SONACOS potting soil and 0.1 kg SONACOS ash (T1C0.1) and 0.1 kg SONACOS ash (T0C0.1) for tomato. However, crop yields were lower in these treatments and are higher in the SONACOS potting soils at 2 kg (TS2) treatment where the frequency of species was high. Finally, the existence of a strong weed competitor was likely to lead to yield losses.

The "System of Rice Intensification"(SRI) represents a sustainable alternative to improve household yields and incomes. This study aimed to evaluate the yields and the profitability of the SRI and the Traditional Practices (TP) in Ziguinchor district, Senegal. A directed sampling based on criteria for selecting the system used and the cultivated varieties common to both systems was applied to collect the yield parameters and yields of paddy rice. Thus, 18 producers in the Badiate, Essyl, and Fanda sites were selected, nine per system and four 1 m2 yield squares were installed in each selected producer plot. A total of 72 yield squares, 36 per system, were installed, and an individual questionnaire was randomly administered to 55 producers using at least one of the systems to collect data on rice production and costs. The yield parameters including the number of fertile tillers per m2, the number of spikes, the weight of the 1000 grains are significantly higher (p

Momordica charantia is a plant species widely used in food and traditional medicine. However, the germination techniques and the performances of M. charantia are poorly understood by the populations. This study aims to better understand the germination, growth and development characteristics, and yield of M. charantia. Three pretreatments of the seeds are used for the shortening of the pre-germination period: soaking the seeds in tap water for 24 hours (batch 2), in hot water at 80˚C (batch 3), for 24 hours and in the boiling water at 100˚C for 24 hours (batch 4). A control without soaking (batch 1) was also carried out. The seeds were sown in plastic boxes in the laboratory with sterile sand and directly in the nursery in polyethylene sleeves. The influence of the light factor (light and dark) and watering frequency (every day and every two days) on the growth and yield parameters was evaluated respectively in the laboratory and in the nursery. Germination, growth and yield parameters were determined. The results show that the light and frequency of watering factors have no influence (p > 0.05) on the rate and duration of seed germination unlike pretreatments. Thus, Batch1 and 2 exhibit significantly higher germination rates (70% ± 16%) than Lots 3 and 4 (21% ± 15%) in the laboratory and in the nursery. On the other hand in terms of germination time, batch 3 and 4 displayed shorter durations (14 days) than those batch1 and 2 (23 days). Growth parameters and yield (fruit and seeds) are strongly influenced by watering frequency, unlike pretreatments which only affect yield. Growth and yield parameters are significantly higher with daily watering than daily watering. Ultimately, this study showed that pretreatments have an influence on the duration and rate of germination as well as the frequency of watering on the performance of M. charantia.

Mango (Mangifera indica L.) is a tree of the family Anacardiaceae, native to southern Asia, widely cultivated in tropical countries for its fruit, the mango. The mango production has achieved worldwide usefulness as a fruit, a medicinal use and a economic importance. Despite the importance of Mangifera indica L. Senegal is facing to the loss of the mango productivity and the decline of mango tree diversity. It is therefore important to improve the selection and the genetically improvement of the rootstocks. This study aims to test the germination, growth and development of Mangifera indica L varieties locally known as Diourou, Siera Leone, Pince and Kouloubadaseky on three types of substrates. The substrates used were three potting of forest soil of Anacardium occidentale, Mangifera indica and Khaya senegalensis. Thus, the nuts of the different varieties were sown in sheaths filled with pure potting forest soil from the different substrates (Anacardium occidentale, Mangifera indica and Khaya senegalensis. A germination test and a follow-up of seedlings on different substrates was carried out in the nursery to determine the effect of substrates on growth parameters. The germination dynamics of the three varieties reveals two peaks the first at the 24th day for Diourou and Kouloubadaseky varieties and another the 34th day for the Siera Leone and Pince varieties on all substrates. And the overall germination rate is 63.22% ± 1.88. The results showed that the number of stems per seed depends on the variety but not on the substrates. The Principal Component Analysis showed significative correlations between parameters such as the number of leaves, the height and the diameter at the crown of the stem. The analysis of variance showed a significant difference (P-value˂0.05) between varieties and according to the substrate on the parameters studied. All this information can be basic use for growers when choosing the varieties and type of substrate for mango rootstock production in their nurseries.

Despite the important socio-economic role of non-timber forest products from the Great Green Wall in Senegal, little is known about their contribution to the local or national economy. This study aims to analyse the value chain of Balanites aegyptiaca and Ziziphus mauritiana fruits in the Sahelian zone of Senegal. To this end, a socio-economic survey was conducted in the Ferlo area (Widou Thiengoly, Amaly, Labgar, Téssékéré and Dahra) and in the major cities where products from the Great Green Wall are sold, namely Dakar, Thiès and Touba. Individual structured interviews were conducted with a questionnaire administered to 260 people in the study sites. The surveys revealed that only fruits of Balanites aegyptiaca (51%) and Ziziphus mauritiana (49%) species are harvested. Harvesting is almost exclusively done by women (98%). The highest usage values obtained from harvesters (3.05) and consumers (1.73) concern B. aegyptiaca. In the Ferlo, the traders surveyed (banabanas) buy the products at the weekly markets in the various villages along the GMV at the survey sites. In the larger towns, the banabanas transport the products to the urban markets to sell them to wholesalers, demigrosalers, retailers and consumers. The lowest price varies from 200 to 300 FCFA for B. aegyptiaca and from 225 to 400 FCFA for Z. mauritiana. The highest price varies from 300 to 450 FCFA for B. aegyptiaca and from 350 to 500 FCFA for Z. mauritiana. This study reveals the strong economic potential of harvesting and selling forest products from GMV and points to the possibility of job creation, which complements the improvement of the food and nutritional status of the rural populations of the Ferlo through the consumption of these fruits. Keywords: Value chain, Balanites aegyptiaca, Ziziphus mauritiana, Ferlo and Senegal., Malgré l’important rôle socio-économique des produits forestiers non ligneux issus de la Grande Muraille Verte au Sénégal, leur contribution à l'économie locale ou nationale est peu connue. Cette étude se propose d’analyser la chaine de valeur des fruits de Balanites aegyptiaca et Ziziphus mauritiana dans la zone sahélienne du Sénégal. A cet effet, une enquête socio-économique a été menée dans la zone du Ferlo (Widou Thiengoly, Amaly, Labgar, Téssékéré et Dahra) et au niveau des grandes villes de revente des produits issus de la Grande Muraille Verte, à savoir Dakar, Thiès et Touba. Des entretiens structurés individuels ont été réalisés avec un questionnaire administré à 260 personnes dans les sites d’étude. Les enquêtes ont révélé que seuls les fruits des espèces de Balanites aegyptiaca (51 %) et de Ziziphus mauritiana (49 %) sont exploités. La récolte est quaisment exclusivement assurée par les femmes (98 %). Les valeurs d’usages les plus importantes obtenues au niveau des récolteurs (3,05) et des consommateurs (1,73) concernent l’espèce B. aegyptiaca. Au Ferlo, les commerçants enquêtés (banabanas) achètent les produits au niveau des marchés hebdomadaires des différents villages situés le long de la GMV, sur les sites d’enquêtes. Dans les grandes villes, les banabanas transportent les produits dans les marchés urbains pour les vendre aux grossistes, demigrossistes, détaillants et consommateurs. Le prix le plus faible varie de 200 à 300 FCFA pour le B. aegyptiaca et de 225 à 400 FCFA pour le Z. mauritiana. Le prix le plus élevé varie de 300 à 450 FCFA pour le B. aegyptiaca et de 350 à 500 FCFA pour le Z. mauritiana. Cette étude révèle le fort potentiel économique de la récolte et de la vente de produits forestiers issus de la GMV et dessine la possibilité de création d'emplois, qui viennent compléter l'amélioration de l'état alimentaire et nutritionnel des populations rurales du Ferlo grâce à la consommation de ces fruits. Mots clés : Chaine de valeurs, Balanites aegyptiaca, Ziziphus mauritiana, Ferlo et Sénégal.

Despite the importance of forests and trees, Senegal is facing to the loss of forests and the decline of tree diversity and density. This study focuses on Moringa oleifera Lam., Acacia mellifera (Vahl) Benth. and Zizyphus mauritiana Lam. which constitute a significant source of food and economic value for the populations of Casamance.In addition to a germination test, a follow-up of seedlings on different substrates was carried out in the nursery, in order to determine the effect of substrates on some growth parameters (number of leaves, height, diameter and biomass).The substrates used were three potting mixtures of forest soil of Faidherbia albida (FSFA), Elaeis guineensis (FSEG) and Anacardium occidentale (FSAO) and sand with the following proportion: 1/3 sand + 2/3 forest soil). Based on species, the germination rate was higher for A. mellifera (84%) followed by M.oleifera (55%) and Z. mauritiana (50%). The germination rate was more important in FSFA and FSEG than in FSAO. For growth parameters, there was a significant effect (P

Tree diversity in West Africa is threatened by intensified land uses and salinization, and farmers’ role in conservation of tree species is unclear. We hypothesized that farmers contribute to conservation of tree diversity through protection of trees in their agroforestry landscapes and compared the diversity and structure of the tree vegetation across landscape classes. Inventories were carried out in three villages in the Groundnut Basin in Senegal, assessing tree diversity, density and crown cover. Tree diversity as assessed by species accumulation curves was high in forests, but cultivated landscapes had comparable or almost comparable diversity, especially in the cases where the forest was planted or was affected by charcoal production. However, the occurrence of exotic species was higher in cultivated parts of the landscape, and although many species were in common, ordination plots indicated that forests and cultivated landscapes to some degree had different species composition. Salinity had a strong influence on vegetation, not only in the tans (salt marshes) but also across the other landscape classes. In conclusion, agroforestry landscapes in the three villages harbor considerable tree diversity, but insufficient to fully conserve the tree species. We argue that informing and including farmers in tree management in the region will contribute to overall conservation of tree genetic resources.

Moringa oleifera and Leucaena leucocephala are two species which constitute a significant food, medicinal and economic source for the populations of Casamance. The objective of this study is to determine the most suitable substrate for good germination and better growth of these species. Thus a completely randomized block design with two factors (species and substrates) repeated four times was installed. The germination rate, the number of leaves, the diameter at the collar, the height, the humidity and the biomass were determined. The results of the germination rate showed that there was no significant difference between the treatments for both M. oleifera and L. leucocephala regardless of the treatment. The number of leaves, the growth in diameter and in height are significantly higher in the plants of the treatment S1 (9.70 leaves / plant; 0.41 cm for the diameter at the collar and 28.05 cm for the average height of the plants) for M.oleifera compared to other treatments (number of leaves P=0.003; diameter at the collar P=0.001 and height P=0.04). With regard to L. leucocephala, no significant difference (P=0.75) was noted for the number of leaves and the diameter at the collar (P=0.19) between the different substrates. The height of the plants of the substrate S3 (13.54 cm) of L. leucocephala is significantly different (P=0.001) compared to the other substrates. The results of the moisture content of the M. oleifera and L. leucocephala plants did not show any significant difference whatever the substrate. Regarding the dry aerial and root biomass of the plants of M. oleifera and L. leucocephala, the results showed that there is no significant difference between the substrates (P=0.46 for M. oleifera and P=0.21 for L. leucocephala).

Improving the quality of people’s diets represents a major challenge for developing countries, particularly in Sahelian African countries. Foods from trees, shrubs, and palms are present in many meals and may improve dietary quality, especially for rural communities but, as their contributions have rarely been quantified, investigating the link between the intake of tree foods and the nutritional composition of diet is important. This study assesses the contribution of tree and palm foods to dietary intake in three rural communities in Senegal, using three household food consumption surveys to quantify the dietary intake of meals. The consumption of tree and palm foods in meals was frequent, mentioned by 93–99% of the families depending on the time of year. Products of 11 tree and palm species were used in meals, with Adansonia digitata (baobab) leaves the most frequently mentioned. The energy contribution of tree and palm foods was low, but their contribution of certain micronutrients was high, w...

Several studies have documented that vegetation in the Sahel is highly dynamic and is affected by the prevailing climatic conditions, as well as by human use of the areas. However, little is known about vegetation dynamics in the large saline areas bordering the rivers of West Africa. Combining satellite imagery, the perception of local people and botanical information, this study investigated the vegetation dynamics and the drivers of vegetation changes in Fatick Province, Senegal. Satellite images showed a change in vegetation composition, i.e., a loss of tree cover and an increase in shrub cover, herbaceous cover and tans (highly saline areas with sparse vegetation). Although the trend was the same, the three villages had different vegetation histories. A survey of the woody vegetation showed that shrubs and young trees were dominating with relatively few large trees. Local people perceived a general decline of woody plants from 1993 to 2013. Among 60 species mentioned by local people, 90 % were declining and 10 % increasing. Together the three methods documented a decrease in density and diversity of the woody vegetation, mainly influenced by salinity and land use. The large numbers of young trees indicate a potential for regeneration of some, but not all, tree species. As many tree species appreciated by local people were reported to be declining, local communities have experienced a reduction of their natural resources. Based on villagers’ recommendations for improved vegetation management, we discuss possible contributions including reforestation, desalinization and environmental protection for restoration of the vegetation.

Elaeis guineensis Jacq is a species of palm commonly called oil palm. It is a source of many products and services. It is used in agroforestry systems. The Elaeis guineensis Jacq parklands or palm groves occupy an important place in the livelihoods of the local population of Guinea Bissau especially in the region of Cacheu where important natural formations were found. However, despite the socio-economic importance of these parklands, their dynamics in the region have been poorly studied. It is in this context that the present study was initiated with the objective of evaluating the current state of the Elaeis guineensis parklands in the region through an ecological characterization. To this end, 90 vegetation surveys of 2500 m2 were carried out in six villages in three sectors of the region, for a total area of 22.5 ha. These surveys revealed a high floristic diversity in the Elaeis guineensis parks in the region. Thus, 75 species divided into 63 genera belonging to 25 families were registered. The parklands are also characterized by a high density of Elaeis guineensis with 775 individuals / ha and 90% of which consist of young plants that often do not reach adulthood. In addition to the difficulties associated with poor recruitment of regeneration, populations of Elaeis guineensis are under heavy human pressure in the area. The mortality rate and the anthropization index, which are respectively 15.97% and 23.35%. These combined factors reveal a certain fragility of the Elaeis guineensis parklands in the Cacheu region. Hence the need to make the inventory that is a prerequisite for any strategy of recovery and sustainable exploitation of the species in order to sustain these production systems.

Located in the East of Wuhan City, Jiufeng Protected area is endowed with a rich biodiversity in diversity landscape (Metasequoia forests, forest ponds, pine forest, Wetland pine, fir, cedar forest, Liquidambar forests, oak forests massoniana and lobular, Lin and mushroom). The objectives of this study were to assess and understand the biodiversity threats, evaluate activities, help prioritize and anticipate what threats might become more severe in the future. Threat assessment was based on a review of peer articles and secondary data sources such as key informant interviews. Interviews with local and provincial authorities and visits in the field were held to gather information on Jiufeng protected area resources and biodiversity threats. This research was carried out on June 2009. The Interviews, the literature review and field report showed that the biodiversity is threatened by a variety of human activities and natural factors such as climate change and invasive alien species. These threats can cause the biodiversity loss. In Jiufeng Protected Area, human activities such as land use and land cover change, industrialization and pollution, tourism and recreation constitute threats for biodiversity.

Salinity and acidity of soils remain one of the world’s oldest and the most serious environmental problem, which substantially hampers crop and ecosystem productivity in arid and semi arid areas. This problem has been addressed by expensive and energy depleting soil reclamation measures. In this study, we tested salinity and acidity tolerances of ten ligneous species. This Investigation was undertaken in the scope of my thesis in the project’’ agrosylvopastoral economic development of saline and acid sulphated soils in Sine-Saloum by ligneous regeneration’’. It was done in the rural communities of Djilass and Loul Secene, sub-prefecture of Fimela, Department and province of Fatick.The study consisted to evaluate the ligneous vegetation tolerance in the experimental plot of the project. The adopted experimental method is a factorial with two factors (type of plot and Species). The first factor (type of plot) has three levels (Pure plot, herbaceous plot and shrubby plot) and the second factor (species) has ten levels (Acacia seyal, Acacia tortilis, Acacia nilotica, Acacia Senegal, Acacia ampliceps, Melaleuca acacioides, Melaleuca viriflora, Prosopis juliflora, Prosopis cineraria and Casuarina equisetifolia). The sites (villages) are taken as repetitions. Three plots are considered in Djilass and Ndoff-Faoye. Each kind of species is planted in 625m2 space and the distance between species is 5m*5m. The holes adopted for plantation are 40cm*40cm*40cm. The measured parameters are survival rate, height and stem diameter of species. The plots characterization permits to know the salinity and the acidity of each plot. All the plots are salted and acid but the salinity and acidity degree vary according to the type of plot. The salinity levels range between EC 1.38 ms/cm and EC 14.02 ms/cm and the ph levels vary from 4.74 to 5.9.The species tolerance depends not only on the salinity and acidity degree but also on the species type. These findings indicate that some species tolerate the salinity and acidity and others are sensitive.