Foliar inputs from indigenous agroforestry tree/shrub provide organic matter and nutrients to sustain crop production in the West African Sahelian region. This study aims at monitoring the decomposition and nutrients release of leafy biomass of selected agroforestry tree and shrub species. In Mali and Burkina Faso, fresh leaves were collected from leguminous trees (Faidherbia albida (Delile) A. Chev., Pterocarpus lucens Lepr.) and non-leguminous trees (Vitellaria paradoxa C.F. Gaertn., Khaya senegalensis (Desr.) A. Juss.) and in Senegal, fresh leaves were obtained from leguminous trees (Faidherbia albida (Delile) A. Chev., Pterocarpus lucens Lepr. and Piliostigma reticulatum (DC.) Hochst.) and the non-leguminous tree Guiera senegalensis J.F. Gmel. The leaf samples collected during the dry and rainy seasons were deployed for decomposition and nutrient release experiments using the litter bag technique. Average decomposition rate for this study was 0.23 k week− 1 whereby the rate of decomposition was 155
Acacia senegal (L.) Wild colonizes the Western Sahel of Mali. This agroforestry species plays an important role in the socio-economic life of local populations. The density of this species has declined sharply recently because of climate change and anthropogenic factors. However, the influence of this density on soil fertility has been documented in very few studies in Mali. This study reports the influence of the density of natural Acacia senegal stands on soil fertility. Three municipalities of the region (Gadiaba, Nioro, and Korokodjo) were selected for the study. At each site, three plots of 2500 m2 each were marked out. The Acacia woody stand within each plot was measured (basal circumference, total height, and circumference total height and circumference at 1.30 m). These measurements were preceded by an exhaustive inventory of the woody plants. Juvenile plants with a circumference of 10 cm were systematically counted and considered as regeneration. In parallel with these measurements, soil samples were taken from the tops and undersides of four-foot trees at the ends and centers of the plots. A 500 g composite sample was taken from these samples. These samples were sent to the Sotuba soil-water-plant laboratory for particle size and chemical analysis. Natural stands are very dense in Gadiaba, with an average of 690 plants/ha, medium density in Nioro, with 430 plants/ha, and very low density in Korokodjo, with 120 plants/ha. The natural stands in the study area are characterized by small, medium-diameter trees. At Gadiaba, the soil is sandy-loamy, while at Nioro and Korokodjo, the proportion of sand dominates at over 90%. The soils were all deficient in organic carbon, nitrogen, and assimilable phosphorus. Comparison of the magnesium content, sand, and silt proportions between the sites studied showed highly significant differences (p ˂ 0.001). The C/N ratios and phosphorus levels were not significantly different between the three sites. The C/N ratio is 4.55% at Gadiaba, 5.95% at Korokodjo and 3.36% at Nioro du Sahel. Phosphorus levels were 3.79% in Gadiaba, 1.73% in Korokodjo, and only 0.21% in Nioro du Sahel. For other mineral elements and pH, however, the differences are significant at the critical threshold of 5%. Therefore, it is important to identify suitable management methods for these resources.
Aims: The aim of this study was to assess the effect of plant extracts Azadirachta indica, Piper nigrum L, Acacia gummifera, Combretum micranthum, and Clenodium vulgare L on rice yellow mottle virus in rice. Study Design: The experiment was conducted in a Randomized Complete Block Design (RCBD) with five repetitions. The blocking factor was the sunshine. Place and Duration of Study: The study was carried out at the Microbiology and Microbial Biotechnology Research Laboratory (LaboREM-Biotech) of the Faculty of Sciences and Techniques, between June and November 2020. Methodology: The rice variety Kogoni91-1, which is highly susceptible to rice yellow mottle, was grown under greenhouse at the LaboREM-Biotech, inoculated with a highly virulent virus from the laboratory's collection and treated with plant extracts. Results: The results showed that rice plants treated with the combination of plant extracts from C. micranthum, A. indica, and C. vulgare recorded higher grain and aerial biomass yields than the positive control and very close to those of the negative control. Similarly, plants treated with black pepper extracts showed a number of spikelets, a yield and an aerial biomass higher than those of the positive control and very close to those of the negative control. Conclusion: Using plant extracts to combat rice yellow mottle could be an alternative to the application of chemical pesticides harmful to human and animal health.
L’Optimisation des ressources en changement climatique passe par la capitalisation/analyse des acquis. L’objectif de cette étude était d’analyser les réalisations dans le domaine au Mali. L’analyse des documents et données, les échanges et travaux de groupe ont prouvé que le pays est doté d’une politique nationale de changement climatique (PNCC) intégrant huit axes stratégiques et 147 plans actions. Les acquis associent, l’Agence pour l’Environnement et le Développement Durable, des lois, décrets, arrêtés et cursus universitaires ; des technologies, pratiques agricoles et semences résilientes ; des aménagements agricoles et un système de riziculture intensif, tous orientées vers une bonne adaptation au changement climatique. Les réalisations portent également sur le Fond Climat Mali qui mobilise les financements dans le domaine ; la quinzaine de l’environnement ; des plans d’aménagement et de gestion forestier ; 09 périmètres pastoraux, 03 réhabilités et 07 sécurisés sur 295 600 ha ; 1910 km de pistes de transhumance balisés et 1510 ha ensemencés de panicum. Le Registre social unifié mise au point permet de protéger les personnes les plus vulnérables. En conclusion, des actions importantes sont enregistrées. Toutefois, des interrogations sur le rythme d’évolution, échelle de mise en œuvre et les impacts restent à examiner.
