Catteau L.,Catholic University of Louvain |
Lautie E.,Catholic University of Louvain |
Kone O.,Catholic University of Louvain |
Coppee M.,Catholic University of Louvain |
And 3 more authors.
Journal of Agricultural and Food Chemistry | Year: 2013
The purpose of this research is to screen different processes that could potentially decrease or even eliminate rotenone, a toxic isoflavonoid, from Pachyrhizus seeds. Yam bean seeds have very interesting nutritional characteristics, especially their high protein and lipid contents, and could potentially increase food security in under-nourished populations. However, they contain rotenone, a natural molecule previously used as an insecticide inhibiting the respiratory mitochondrial chain. It was also proven to be toxic to mammals as chronic exposure leads to the development of Parkinson-like symptoms in rats. As the thermosensitivity of rotenone had been reported, this study tested different processes (drying, roasting, boiling, frying, alcohol extraction), tegument removal, and traditional Beninese culinary recipes. Rotenone was then quantified in end-products by a validated method, associating microwave extraction, solid phase extraction (SPE), and HPLC-UV. With these processes a rotenone removal of up to 80% was obtained. The most effective methods were the drying and roasting of the seeds and the maceration of their flour in local alcohol. Rotenone degradation and elimination were confirmed by cytotoxic assays, effectively inducing a decrease in sample toxicity. © 2013 American Chemical Society.
Schut M.,Wageningen University |
Schut M.,International Institute Of Tropical Agriculture |
Klerkx L.,Wageningen University |
Rodenburg J.,Africa Rice Center |
And 6 more authors.
Agricultural Systems | Year: 2015
This paper introduces Rapid Appraisal of Agricultural Innovation Systems (RAAIS). RAAIS is a diagnostic tool that can guide the analysis of complex agricultural problems and innovation capacity of the agricultural system in which the complex agricultural problem is embedded. RAAIS focuses on the integrated analysis of different dimensions of problems (e.g. biophysical, technological, socio-cultural, economic, institutional and political), interactions across different levels (e.g. national, regional, local), and the constraints and interests of different stakeholder groups (farmers, government, researchers, etc.). Innovation capacity in the agricultural system is studied by analysing (1) constraints within the institutional, sectoral and technological subsystems of the agricultural system, and (2) the existence and performance of the agricultural innovation support system. RAAIS combines multiple qualitative and quantitative methods, and insider (stakeholders) and outsider (researchers) analyses which allow for critical triangulation and validation of the gathered data. Such an analysis can provide specific entry points for innovations to address the complex agricultural problem under study, and generic entry points for innovation related to strengthening the innovation capacity of agricultural system and the functioning of the agricultural innovation support system. The application of RAAIS to analyse parasitic weed problems in the rice sector, conducted in Tanzania and Benin, demonstrates the potential of the diagnostic tool and provides recommendations for its further development and use. © 2014 The Authors.
De Clercq E.M.,Catholic University of Louvain |
Leta S.,Adami Tullu Agricultural Research Center |
Estrada-Pena A.,Veterinary Faculty |
Madder M.,Institute of Tropical Medicine |
And 3 more authors.
Preventive Veterinary Medicine | Year: 2015
Rhipicephalus microplus is one of the most widely distributed and economically important ticks, transmitting Babesia bigemina, B. bovis and A. naplasma marginale. It was recently introduced to West Africa on live animals originating from Brazil. Knowing the precise environmental suitability for the tick would allow veterinary health officials to draft vector control strategies for different regions of the country. To test the performance of modelling algorithms and different sets of environmental explanatory variables, species distribution models for this tick species in Benin were developed using generalized linear models, linear discriminant analysis and random forests. The training data for these models were a dataset containing reported absence or presence in 104 farms, randomly selected across Benin. These farms were sampled at the end of the rainy season, which corresponds with an annual peak in tick abundance. Two environmental datasets for the country of Benin were compared: one based on interpolated climate data (WorldClim) and one based on remotely sensed images (MODIS). The pixel size for both environmental datasets was 1. km. Highly suitable areas occurred mainly along the warmer and humid coast extending northwards to central Benin. The northern hot and drier areas were found to be unsuitable. The models developed and tested on data from the entire country were generally found to perform well, having an AUC value greater than 0.92. Although statistically significant, only small differences in accuracy measures were found between the modelling algorithms, or between the environmental datasets. The resulting risk maps differed nonetheless. Models based on interpolated climate suggested gradual variations in habitat suitability, while those based on remotely sensed data indicated a sharper contrast between suitable and unsuitable areas, and a patchy distribution of the suitable areas. Remotely sensed data yielded more spatial detail in the predictions. When computing accuracy measures on a subset of data along the invasion front, the modelling technique Random Forest outperformed the other modelling approaches, and results with MODIS-derived variables were better than those using WorldClim data. © 2014 The Authors.
Kone B.,University of Benin |
Amadji G.L.,UAC |
Aliou S.,UAC |
Diatta S.,University of Benin |
Akakpo C.,Institute National des Recherches Agricoles du Benin INRAB
Archives of Agronomy and Soil Science | Year: 2011
With the objective of improving rice productivity and generating additional knowledge on rice production in Africa, field experiments were conducted for two consecutive seasons of 2005 and 2006 in Southern Benin. Terre de barre soils at the WARDA experimental station and Niaouli, and the plinthic Ferralsols of Cana were investigated. A complete fertilizer (Fc) composed of N, P, K, Ca, Mg and Zn was used to assess NERICA.4 (upland rice) root development and grain yield (GY). Similar observations were made in treatments with a specific nutrient excluded from Fc (Fc-N, Fc-P, Fc-K, Fc-Ca, Fc-Mg and Fc-Zn). A grain yield of up to 1.4 t ha-1 (Fc-N) and higher root densities for Fc and Fc-Mg at 20-60 cm were attained. Maximum reductions in yield and rooting depth were observed for Fc-P (27%, 27%), Fc-K (30%, 14%) and Fc-Zn (32%, 2%). Drought occurrence, a high C/N ratio and soil acidity influence the effects of nutrients on rice. Removal of N from basal fertilizer was recommended to reduce the effect of mid-season drought. It is suggested that the critical level of K in the soils of West Africa be adjusted to 0.40 cmol kg-1 for upland rice. © 2011 Copyright Taylor and Francis Group, LLC.
N'Djolosse K.,Institute National des Recherches Agricoles du Benin INRAB |
Atachi P.,University Abomey Calavi |
Gnangle C.P.,Institute National des Recherches Agricoles du Benin INRAB
International Journal of Tropical Insect Science | Year: 2012
Shea parklands have a great socio-economic, cultural and ecological interest but suffer pest attack, which is among the major causes for their deterioration in Africa. To establish an inventory of insects associated with shea trees, the foliage, stems and fruits were regularly examined on 180 trees randomly chosen at six sites in the central and northern regions of Benin. From June to October 2010, a total of 196 samples containing 1415 specimens were collected. These insects belong to 8 orders, 36 families and 56 genera. Forty-seven insects were identified to the species level. The defoliator Cirina forda (Westwood) and the stemborer Neoplocaedaerus spp. were the two most damaging insect species occurring on shea trees. This study stresses the need to protect the shea parklands in Benin through the implementation of integrated insect pest management strategies against shea tree pests. © ICIPE 2012.
Akele G.D.,University Abomey Calavi |
Agadjihouede H.,University Abomey Calavi |
Mensah G.A.,Institute National des Recherches Agricoles du Benin INRAB |
Laleye P.A.,University Abomey Calavi
Knowledge and Management of Aquatic Ecosystems | Year: 2015
Etheria elliptica (Bivalvia: Etheriidae) is the only freshwater oyster occurring in Africa. The current study provides the first data on the population structure, growth, age, mortality and exploitation status of this species in the Pendjari River. E. elliptica length-frequency data were collected monthly from January to December 2009 and analyzed with FiSAT software. Population parameters including the asymptotic length (L∞) and growth coefficient (K) were assessed to evaluate the stock status. The recruitment pattern was modeled with a FiSAT routine. The asymptotic length (L∞) was 14.75 cm, while the growth coefficient (K) was 0.38 year-1. The growth performance index (∅′) reached 1.92. Specimens of Etheria elliptica reached a mean size of 4.66 cm and 6.41 cm at the end of one year and 1.5 years, respectively. We estimated total mortality (Z), natural mortality (M) and fishing mortality (F) to be 2.90 year-1, 1.16 year-1 and 1.74 year-1, respectively. The recruitment pattern was continuous over the year with one major peak event during the rainy season (July). The exploitation rate (E = 0.60) revealed that the freshwater oyster was probably facing overexploitation due to lack of a minimum limit size and also due to an increase in the harvesting effort. Therefore, efficient management methods were urgently required to conserve the species. The return of empty shells into the water to increase the recruitment surface, rotation planning among harvesting sites and the imposition of a minimum limit size were recommendations made in order to ensure the sustainable exploitation of wild stocks. © ONEMA, 2015.
Togbe C.E.,University Abomey Calavi |
Togbe C.E.,Wageningen University |
Vodouhe S.D.,University Abomey Calavi |
Gbehounou G.,Institute National des Recherches Agricoles du Benin INRAB |
And 5 more authors.
International Journal of Agricultural Sustainability | Year: 2014
The immediate consequences of the 2009 reform of the cotton sector in Benin are assessed from the farmers' perspective. Using a policy arrangements approach, we analyse how farmers experienced the transformations brought about by the reform and how it influenced their day-to-day activities. The new farmer cooperatives established after the reform were trusted by farmers. Many farmers returned to the sector, increasing cotton output. Nevertheless, productivity remained low, around 900 kg/ha, probably because the reform addressed mainly institutional constraints. Technical constraints relating to varietal choice, soil fertility improvement, and pest management were neglected. The policy arrangements emerging from the reform still generate discussion, in particular about the way actors and coalitions are organized. The top-down approach of the reform process has limitations for problem-solving, especially where actors' interests collide. The adjustments made under the reform with regard to farmer-based organizations and actors from public services, the caution solidaire, and farmers' supervision proved inappropriate for solving the institutional problems posed at the nodes of actors and coalitions, resources, discourses, and institutions, thereby further undermining the cotton sector. A mix of technological and institutional reforms might offer a more effective option for the future. © 2014 © 2014 Taylor & Francis.
Togbe C.E.,University Abomey Calavi |
Togbe C.E.,Wageningen University |
Haagsma R.,Wageningen University |
Zannou E.,University Abomey Calavi |
And 5 more authors.
Journal of Applied Entomology | Year: 2015
Neem oil (Azadirachta indica A. Juss) alone and combined with the entomopathogenic fungus Beauveria bassiana (Balsamo) Vuillemin (isolate Bb11) was applied to control cotton pests. The efficacy of these treatments was compared with that of synthetic insecticides applied either in a calendar-based application or in the 'Lutte Etagée Ciblée' (LEC) strategy, consisting of using first calendar-based (half-dose) applications followed by threshold-based treatments. The experiment was carried out in collaborative research with farmers in three cotton agro-ecological zones differing in rainfall, pest prevalence, and farming practices. The neem oil and neem oil-Bb11 treatments required 2 to 6 applications, while conventional and LEC received 6 to 8 applications. The percentage of damaged reproductive organs in plots treated with neem oil and neem oil plus Bb11 was higher than that recorded under the conventional and LEC strategy, with exception of the zone with the highest rainfall; this resulted in yields being 25% and 39% lower, respectively. Yields in the biopesticide plots were 26-42% higher and in the conventional and LEC plots 44-59% higher than those in the control plots that received only water. Overall, the LEC regime scored best, both in yield and profitability. The incidence of natural enemies was highest in the control and in the plots treated with biopesticides. Although the use of entomopathogen Bb11 and neem oil avoids many problems associated with the application of synthetic insecticides, their efficacy needs to be enhanced by improved formulation or by combining them with other pesticides. © 2014 Blackwell Verlag GmbH.
Maliki R.,Institute National des Recherches Agricoles du Benin INRAB |
Toukourou M.,Institute National des Recherches Agricoles du Benin INRAB |
Sinsin B.,Faculte Des Science Agronomiques Of Luniversite Dabomey Calavi Fsa Uac |
Vernier P.,CIRAD - Agricultural Research for Development
Nutrient Cycling in Agroecosystems | Year: 2012
The principal driving force in agricultural research is to increase the yield of food crops. For farming to remain productive, it will be necessary to replenish the nutrients removed or lost from the soil. The objective of this study was to determine the impact of yam-based systems on soil productivity (dry matter production, nutrients recycled or removed, profitability and soil fertility changes). We compared smallholders' traditional systems (1-year fallow of Andropogonon gayanus -yam rotation; maize-yam rotation) with yam-based systems with legumes (intercropped Aeschynomene histrix with maize-yam rotation; intercropped Mucuna pruriens with maize-yam rotation). The production of dry matter (tubers, shoots), nutrients removed or recycled, and soil properties were significantly improved on yam-based systems with legumes in comparison with traditional systems. Year × Treatment interactions influenced significantly the tuber dry matter production. Site × Treatment and Treatment × Farmer interactions affected significantly nutrients removed or recycled. The amount of nutrients recycled or removed was dependent on the dry matter production that, in turn, depended on soil fertility, rainfall and farmers' effect. Yam-based systems with legumes brought a higher present value than traditional systems in the first 4 years and appeared attractive for land, labour and cash productivities. © 2011 Springer Science+Business Media B.V.
Singbo A.G.,Wageningen University |
Singbo A.G.,Institute National des Recherches Agricoles du Benin INRAB |
Lansink A.O.,Wageningen University
Food Security | Year: 2010
This paper uses a directional distance function and a single truncated bootstrap approach to investigate inefficiency of lowland farming systems in the Benin Republic. First, we employed a dual approach to estimate and decompose short-run profit inefficiency of each farming system into pure technical, allocative and scale inefficiency and also into input and output inefficiency. Second, an econometric analysis of factors affecting the inefficiency was generated using a single truncated bootstrap procedure to improve inefficiency analysis statistically and obtain consistent estimates. In the short run, scale, allocative and output inefficiency were found to be the main sources of inefficiency. Based on inefficiency results, the inefficiency of lowland farming systems is the most diverse. Compared to a vegetable farming system, technical inefficiency is significantly higher if farmers switch to a rice farming system. Scale, allocative, output, and input inefficiency are significantly lower with an integrated rice-vegetable farming system and there was high prevalence of increasing returns to scale in the integrated rice-vegetable farming system. Water control and lowland farming systems are complements and play a significant role in the level of inefficiency. Input inefficiency shows the difficulty that the producers face in adjusting the quality and quantity of seeds and fertilizers. The paper provides empirical support for efforts to promote an integrated rice-vegetable farming system in West Africa lowlands to increase food security. © 2010 The Author(s).