Allal F.,CIRAD - Agricultural Research for Development |
Sanou H.,Institute dEconomie Rurale |
Millet L.,CIRAD - Agricultural Research for Development |
Vaillant A.,CIRAD - Agricultural Research for Development |
And 5 more authors.
Heredity | Year: 2011
The evolution of the savanna biome has been deeply marked by repeated contraction/expansion phases due to climate perturbations during the Quaternary period. In this study, we investigated the impact of the last glacial maximum (LGM) on the present genetic pattern of Vitellaria paradoxa (shea tree), a major African savanna tree. A range-wide sampling of the species enabled us to sample 374 individuals from 71 populations distributed throughout sub-Sahelian Africa. Trees were genotyped using 3 chloroplasts and 12 nuclear microsatellites, and were sequenced for 2 polymorphic chloroplast intergenic spacers. Analyses of genetic diversity and structure were based on frequency-based and Bayesian methods. Potential distributions of V. paradoxa at present, during the LGM and the last interglacial period, were examined using DIVA-GIS ecological niche modelling (ENM). Haplotypic and allelic richness varied significantly across the range according to chloroplast and nuclear microsatellites, which pointed to higher diversity in West Africa. A high but contrasted level of differentiation was revealed among populations with a clear phylogeographic signal, with both nuclear (F ST = 0.21; R ST = 0.28; R ST > R ST (permuted)) and chloroplast simple sequence repeats (SSRs) (G ST = 0.81; N ST = 0.90; N ST > N ST (permuted)). We identified a strong geographically related structure separating western and eastern populations, and a substructure in the eastern part of the area consistent with subspecies distinction. Using ENM, we deduced that perturbations during the LGM fragmented the potential eastern distribution of shea tree, but not its distribution in West Africa. Our main results suggest that climate variations are the major factor explaining the genetic pattern of V. paradoxa. © 2011 Macmillan Publishers Limited All rights reserved.
Davrieux F.,CIRAD - Agricultural Research for Development |
Allal F.,CIRAD - Agricultural Research for Development |
Piombo G.,CIRAD - Agricultural Research for Development |
Kelly B.,Institute dEconomie Rurale |
And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
The Shea tree (Vitellaria paradoxe) is a major tree species in African agroforestry systems. Butter extracted from its nuts offers an opportunity for sustainable development in Sudanian countries and an attractive potential for the food and cosmetics industries. The purpose of this study was to develop near-infrared spectroscopy (NIRS) calibrations to characterize Shea nut fat profiles. Powders prepared from nuts collected from 624 trees in five African countries (Senegal, Mali, Burkina Faso, Ghana and Uganda) were analyzed for moisture content, fat content using solvent extraction, and fatty acid profiles using gas chromatography. Results confirmed the differences between East and West African Shea nut fat composition: eastern nuts had significantly higher fat and oleic acid contents. Near infrared reflectance spectra were recorded for each sample. Ten percent of the samples were randomly selected for validation and the remaining samples used for calibration. For each constituent, calibration equations were developed using modified partial least squares (MPLS) regression. The equation performances were evaluated using the ratio performance to deviation (RPDP) and Rp 2 parameters, obtained by comparison of the validation set NIR predictions and corresponding laboratory values. Moisture (RPDP = 4.45; R p 2 = 0.95) and fat (RPDP = 5.6; R p 2 = 0.97) calibrations enabled accurate determination of these traits. NIR models for stearic (RPDp = 6.26; Rp 2 = 0.98) and oleic (RPDP = 7.91; Rp 2= 0.99) acids were highly efficient and enabled sharp characterization of these two major Shea butter fatty acids. This study demonstrated the ability of near-infrared spectroscopy for high-throughput phenotyping of Shea nuts. © 2010 American Chemical Society.
Agency: European Commission | Branch: FP7 | Program: CP-IP-SICA | Phase: KBBE.2010.1.2-03 | Award Amount: 4.94M | Year: 2011
EAU4Food seeks to address the need for new approaches to increase food production in irrigated areas in Africa, while ensuring healthy and resilient environments. Potential pitfalls of introducing innovations in local farming systems, like limited adoption by farmers and trade-off effects to other (environmental) systems are overcome by, respectively, i) utilizing a true transdisciplinary approach, which involves the active participation of all stakeholders in all relevant disciplines, and ii) by determining and respecting so called sustainable production thresholds. EAU4Food is executed in four irrigated areas in Africa, viz. Southern Africa (Mozambique and South-Africa), Tunisia, Mali and Ethiopia to fully benefit from the potential of cross distributing promising strategies and innovations. At each site, key indicators, risk factors, farm strategies and biophysical parameters are monitored for identification of current constraints to food production and to evaluate agro-ecological and socio-economic impacts of improved practices and/or innovations after implementation. Results of EAU4Food are distilled into tailor made support tables and guidelines for different user groups. These support tables and guidelines support decision making processes at local level by overseeing short-term and long-term effects of alternative practices and improved strategies. EAU4Food is expected to have significant positive impacts on agricultural production at farm level for many years to come, and on wider policy processes at national and trans-national levels. To enlarge and maintain the impact of EAU4Food, capacity building programmes are developed at different levels, going from farmer to farmer exchange up to exchange of scientific personnel. Moreover, further exploitation of the results of EAU4Food is supported via other mediums such as songs of success, documentaries, school programmes, policy briefs, fact-books and scientific publications and presentations.
Agency: European Commission | Branch: FP7 | Program: CP-FP-SICA | Phase: KBBE.2012.2.3-05 | Award Amount: 3.84M | Year: 2013
Food security is a global challenge. Within the overall increased demand for food, and particularly meat production, there is also an urgent need to increase supply of protein from sustainable sources. The principle objective of the international and multidisciplinary PROteINSECT consortium is to facilitate the exploitation of insects as an alternative protein source for animal and human nutrition. Advances have been made in rearing of insects for incorporation in animal feed in countries including China and Mali. The consortium brings together expertise in these countries together with European insect breeders and feed production companies in order to optimise systems and set up pilot scale production facilities in the EU. The project will demonstrate the feasibility of the use of insect-derived proteins in animal feed through trials with fish, poultry and pigs. Quality and safety along the food chain from insect protein itself, to incorporation in feed and ultimately human consumption of insect-protein reared livestock, will be evaluated. The use of waste streams that focus on animal rather than plant material for insect rearing will be examined. To optimise the economic viability of the use of insect proteins, uses for the residual flows from the production system will be determined. Life cycle analyses will enable the design of optimised and sustainable production systems suitable for adoption in both ICPC and European countries. Key to uptake is ensuring that a regulatory framework is in place and this will be encouraged by the preparation of a White Paper following consultation with key stakeholders, experts and consumers. PROteINSECT will build a pro-insect platform in Europe to encourage adoption of sustainable protein production technologies in order to reduce the reliance of the feed industry on plant/fish derived proteins in the short term, and promote the acceptance of insect protein as a direct component of human food in the longer term.
Ndjiondjop M.N.,Africa Rice Center |
Futakuchi K.,Africa Rice Center |
Cisse F.,Institute dEconomie Rurale |
Baimey H.,IITA Benin |
Bocco R.,Africa Rice Center
Crop Science | Year: 2012
A total of 327 rice (Oryza spp.) genotypes were screened for tolerance to drought at the Africa Rice Center in Cotonou, Benin, in 2007 and 2008. Plants were subjected to full irrigation from sowing to harvest or to 21-d drought from 34 d after sowing. Drought-affected plants showed narrower leaves, reduced grain yield, and shorter stature. Tillering and plant maturity were negatively affected by drought whereas values for leaf temperature and leaf greenness were significantly higher under drought than under control condition. Under control condition, for 54% of genotypes, flowering occurred between 71 and 90 d after sowing. But under drought, flowering occurred at 90 or more days after sowing for the majority of genotypes. Significant genotype × environment interactions were observed for plant height, leaf greenness, flowering, grain yield, maturity, leaf rolling, and leaf tip burning. More traits were correlated with grain yield under drought for Oryza glaberrima Steud. than for other genotype groups. No relationship was observed between plant recovery ability and all other traits selected. More than 90% of plants evaluated resumed growth after drought in both years. TOG6208, TOG5691, TOG5591, TOG6594, and RAM122 were identify ed as best performing genotypes in terms of grain yield under drought. Their performance was similar to that of most of the 24 top yielding in terms of leaf rolling, leaf tip burning, and plant recovery after drought release. © Crop Science Society of America.
Agency: European Commission | Branch: FP7 | Program: CSA | Phase: ICT-2007.6.3 | Award Amount: 1.27M | Year: 2008
The ADA project aims at acquiring and sharing knowledge about affordable ICT (Information and Communication Technologies) solutions in Africa with the ambition to reduce the risk of natural disasters and to improve the capacity to respond to disasters.Many Developing Countries in Africa are exposed to serious natural disaster risks and their need for an adequate ICT infrastructure supporting DRM is high. Unfortunately, access to ICT knowledge and affordable ICT systems is often lacking.The ADA project will1. assess the natural hazards, the vulnerability of the communities and the disaster risks in Africa; and2. assess the role of ICT based systems in each hazard category; and3. explore the ICT trends and needs for the future; and4. test the usefulness of GEONETCast as an alert system; and5. share this information with all DRM stakeholders in Africa (by workshops and other); and6. prepare 3 showcases of operational African DRM systems for demo on these workshops; and7. promote and support the take-up of this technology for use in other disasters; and8. liaise with any new project in DRM with a significant involvement of African partners.ADA will test whether the existing GEONETCast infrastructure can be reused as a component of an alert or emergency system. ADA sets up a testcase in South-Africa where the Forest Fire Association in Nelspruit, South-Africa will use the wildfire-alarms from CSIR within their operational activities to fight wildfires. If successful, many DRM systems can benefit from this technology.The project is envisioned to have a big impact with a limited budget, by close cooperation with the AARSE and EUMETSAT conferences and within the UNeDRA network.This effort will support authorities in Developing Countries in setting up their National Disaster Action Plans (as required by the Hyogo agreements) by offering knowledge about working ICT solutions and help them to better manage their disaster risks.
Agency: European Commission | Branch: FP7 | Program: CP-SICA | Phase: KBBE-2008-1-2-05 | Award Amount: 3.81M | Year: 2009
The increasing demand of livestock products, larger climate uncertainty and resource degradation, and the rampant poverty of farmers in the semi-arid tropics calls for modernized agroforestry systems (AFS) capable of providing multiple functions. The project will develop regionally specific, trait-based and field tested AFS capable of providing critical agro-ecosystem functions in semi-arid Africa and Central America. The primary objective is to provide farmers with a portfolio of regionally suitable tree and shrub species organized by their traits or attributes, in relation to the provisioning of multiple services, as perceived by the farmers and in terms of fundamental ecological functions. The project will make substantial contributions to AF and ecological science through its integration of theories and concepts from both fields, and will thereby provide a scientifically based model for the design of modernized AFS. The project will identify, and characterize the main factors influencing the adoption/non adoption of AF in selected target areas. It will improve the performance of AFS in dry and marginal areas with particular focus on how species can be assembled according to their traits to improve the multi-functionality of AFS and will identify the potential of new multipurpose tree species suitable for AF in dry and marginal areas by grouping these species according to their functional traits and their capacity to provide critical AFS services. The project will specifically enhance the synergies between the species traits and model how trait combinations contribute to the multi-functionality of AFS including soil, trees, crop/pasture and livestock. We will evaluate the short and medium environmental impacts of AF and its socio-economic implications through sophisticated interdisciplinary models and will produce policy recommendations aimed at promoting AFS and related husbandry practices best adapted to specific local needs, yet universal in scope.
Benjaminsen T.A.,Norwegian University of Life Sciences |
Aune J.B.,Norwegian University of Life Sciences |
Sidibe D.,Institute dEconomie Rurale
Geoforum | Year: 2010
The aim of this article is to analyse the influence of commodified cotton production on soil fertility in southern Mali. From the late 1950s and until recently, production of both cash-crop cotton and food crops have increased rapidly in this region, giving it a reputation of being an African 'success story'. The flip side of this economic success is, however, said to be environmental degradation especially in terms of loss of soil fertility. We collected 273 soil samples in 19 villages located in various zones of land use intensity. In each village, the samples were collected on up to six different land use types varying with intensification. The analysis of the soil samples showed that soil fertility was highest in the sacred groves that have been protected and never cultivated. However, comparing soils under continuous cultivation and soils under fallow no clear trends in soil fertility were found. Cotton yields have declined since the early 1990s, while the total use of fertilisers has increased. This is often interpreted as proof of soil exhaustion, but there is no clear indication in this study that cotton-cereal rotation as practiced by smallholders in southern Mali reduces soil fertility. We argue that the decline in yields has been caused by an extensification process. Cotton fields expanded rapidly, due to attractive cotton prices in the 1990s, leading to falling investments per ha and cultivation of more marginal lands. These findings also have implications for a political ecology of commodity production and lead us to argue for an open-ended and empirically based 'critical political ecology'. © 2010 Elsevier Ltd.
Logossa Z.A.,University of Lomé |
Camus-Kulandaivelu L.,Institute dEconomie Rurale |
Allal F.,Institute dEconomie Rurale |
Vaillant A.,Institute dEconomie Rurale |
And 3 more authors.
Molecular Ecology | Year: 2011
While the genetic structure of many tree species in temperate, American and Asian regions is largely explained by climatic oscillations and subsequent habitat contractions and expansions, little is known about Africa. We investigated the genetic diversity and structure of shea tree (Vitellaria paradoxa,) in Western Africa, an economically important tree species in the Sudano-Sahelian zone. Eleven nuclear microsatellites (nuc) were used to genotype 673 trees selected in 38 populations. They revealed moderate to high within-population diversity: allelic richness ranged from R nuc = 3.99 to 5.63. This diversity was evenly distributed across West Africa. Populations were weakly differentiated (F STnuc = 0.085; P < 0.0001) and a pattern of isolation by distance was noted. No phylogeographic signal could be detected across the studied sample. Additionally, two chloroplast microsatellite loci, leading to 11 chlorotypes, were used to analyse a sub-set of 370 individuals. Some variation in chloroplast allelic richness among populations could be detected (R cp = 0.00 to 4.36), but these differences were not significant. No trend with latitude and longitude were observed. Differentiation was marked (G STcp = 0.553; P < 0.0001), but without a significant phylogeographical signal. Population expansion was detected considering the total population using approximate Bayesian computation (nuclear microsatellites) and mismatch distribution (chloroplast microsatellites) methods. This expansion signal and the isolation by distance pattern could be linked to the past climatic conditions in West Africa during the Pleistocene and Holocene which should have been favourable to shea tree development. In addition, human activities through agroforestry and domestication (started 10 000 bp) have probably enhanced gene flow and population expansion. © 2011 Blackwell Publishing Ltd.
Weber J.C.,World Agroforestry Center |
Mounkoro B.,World Agroforestry Center |
Dakouo J.-M.,Institute dEconomie Rurale
Development in Practice | Year: 2010
Native species of trees and shrubs contribute significantly to farmers' livelihoods by supplying food, medicinal products, fodder, and wood. In the case study reported in this article, this contribution to farmers' annual revenue varied from 26 per cent to 73 per cent, and was as high as US$ 650 a year for households for which agroforestry products were the primary source of revenue. Household consumption was not quantified in the study, but farmers' comments confirmed that native trees also played an important role in assuring food security, especially in the 'hunger period' when grain stores are low and farmers are waiting for the next harvest. © 2010 Taylor & Francis.