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Bamako, Mali

Ruiz-Carrasco K.,University of Bologna | Antognoni F.,University of Bologna | Coulibaly A.K.,University du Mali | Lizardi S.,University of La Serena | And 5 more authors.
Plant Physiology and Biochemistry | Year: 2011

Chenopodium quinoa (Willd.) is an Andean plant showing a remarkable tolerance to abiotic stresses. In Chile, quinoa populations display a high degree of genetic distancing, and variable tolerance to salinity. To investigate which tolerance mechanisms might account for these differences, four genotypes from coastal central and southern regions were compared for their growth, physiological, and molecular responses to NaCl at seedling stage. Seeds were sown on agar plates supplemented with 0, 150 or 300. mM NaCl. Germination was significantly reduced by NaCl only in accession BO78. Shoot length was reduced by 150. mM NaCl in three out of four genotypes, and by over 60% at 300. mM (except BO78 which remained more similar to controls). Root length was hardly affected or even enhanced at 150. mM in all four genotypes, but inhibited, especially in BO78, by 300. mM NaCl. Thus, the root/shoot ratio was differentially affected by salt, with the highest values in PRJ, and the lowest in BO78. Biomass was also less affected in PRJ than in the other accessions, the genotype with the highest increment in proline concentration upon salt treatment. Free putrescine declined dramatically in all genotypes under 300. mM NaCl; however (spermidine. +. spermine)/putrescine ratios were higher in PRJ than BO78. Quantitative RT-PCR analyses of two sodium transporter genes, CqSOS1 and CqNHX, revealed that their expression was differentially induced at the shoot and root level, and between genotypes, by 300. mM NaCl. Expression data are discussed in relation to the degree of salt tolerance in the different accessions. © 2011 Elsevier Masson SAS. Source

Ruiz K.B.,University of Chile | Biondi S.,University of Bologna | Antognoni F.,University of Bologna | Martinez-Mosqueira E.A.,Catolica del Norte University | And 7 more authors.
Agronomy for Sustainable Development | Year: 2014

Climate change is rapidly degrading the conditions of crop production. For instance, increasing salinization and aridity is forecasted to increase in most parts of the world. As a consequence, new stress-tolerant species and genotypes must be identified and used for future agriculture. Stress-tolerant species exist but are actually underutilized and neglected. Many stress-tolerant species are indeed traditional crops that are only cultivated by farmers at a local scale. Those species have a high biodiversity value. Besides, the human population will probably reach nine billion within coming decades. To keep pace with population growth, food production must increase dramatically despite the limited availability of cultivable land and water. Here, we review the benefits of quinoa, Chenopodium quinoa Willd., a seed crop that has endured the harsh bioclimatic conditions of the Andes since ancient times. Although the crop is still mainly produced in Bolivia and Peru, agronomic trials and cultivation are spreading to many other countries. Quinoa maintains productivity on rather poor soils and under conditions of water shortage and high salinity. Moreover, quinoa seeds are an exceptionally nutritious food source, owing to their high protein content with all essential amino acids, lack of gluten, and high content of several minerals, e.g., Ca, Mg, Fe, and health-promoting compounds such as flavonoids. Quinoa has a vast genetic diversity resulting from its fragmented and localized production over the centuries in the Andean region, from Ecuador to southern Chile, and from sea level to the altiplano. Quinoa can be adapted to diverse agroecological conditions worldwide. Year 2013 has therefore been declared the International Year of Quinoa by the United Nations Food and Agriculture Organization. Here, we review the main characteristics of quinoa, its origin and genetic diversity, its exceptional tolerance to drought and salinity, its nutritional properties, the reasons why this crop can offer several ecosystem services, and the role of Andean farmers in preserving its agrobiodiversity. Finally, we propose a schematic model integrating the fundamental factors that should determine the future utilization of quinoa, in terms of food security, biodiversity conservation, and cultural identity. © 2013 INRA and Springer-Verlag France. Source

Berthelemy J.-C.,University of Paris Pantheon Sorbonne | Thuilliez J.,University of Paris Pantheon Sorbonne | Doumbo O.,University du Mali | Gaudart J.,Aix - Marseille University
Malaria Journal | Year: 2013

Background: In spite of massive efforts to generalize efficient prevention, such as insecticide-treated mosquito nets (ITN) or long-lasting insecticidal nets (LLINs), malaria remains prevalent in many countries and ITN/LLINs are still only used to a limited extent. Methods. This study proposes a new model for malaria economic analysis by combining economic epidemiology tools with the literature on poverty traps. A theoretical model of rational protective behaviour in response to malaria is designed, which includes endogenous externalities and disease characteristics. Survey data available for Uganda provide empirical support to the theory of prevalence-elastic protection behaviours, once endogeneity issues related to epidemiology and poverty are solved. Results: Two important conclusions emerge from the model. First, agents increase their protective behaviour when malaria is more prevalent in a society. This is consistent with the literature on «prevalence-elastic behaviour». Second, a 'malaria trap' defined as the result of malaria reinforcing poverty while poverty reduces the ability to deal with malaria can theoretically exist and the conditions of existence of the malaria trap are identified. Conclusions: These results suggest the possible existence of malaria traps, which provides policy implications. Notably, providing ITN/LLINs at subsidized prices is not sufficient. To be efficient an ITN/LLINs dissemination campaigns should include incentive of the very poor for using ITN/LLINs. © 2013 Berthélemy et al.; licensee BioMed Central Ltd. Source

Manoukis N.C.,United States Pacific Basin Agricultural Research Center | Baber I.,University du Mali | Diallo M.,University du Mali | Sogoba N.,University du Mali | Ribeiro J.M.C.,National Institute of Allergy and Infectious Diseases
PLoS ONE | Year: 2011

The direction and magnitude of movement by the malaria vector Anopheles gambiae Giles has been of great interest to medical entomologists for over 70 years. This direction of movement is likely to be affected by many factors, from environmental conditions and stage of life history of the mosquito to the existence of attractants in the vicinity. We report here the direction of movement of newly emerged An. gambiae in nature, around the village of Donéguébougou, Mali. We assessed the direction of movement for individual mosquitoes by placing them in a novel enclosure with exit traps oriented in the direction of the cardinal and intermediate points of the compass. We consistently found predominantly Southward directions of movement during 2009 and 2010, with an additional Eastward component during the dry season and a Westward one during the wet season. Our data indicate that wind has an important effect on the direction of movement, but that this effect varied by season: Average directions of movement were downwind during the dry season and upwind during the wet season. A switch in anemotactic response suggests that the direction of movement of An. gambiae relative to the wind immediately after emergence under varying conditions of humidity should be further investigated under controlled conditions. Source

Baber I.,University du Mali | Keita M.,University du Mali | Sogoba N.,University du Mali | Konate M.,University du Mali | And 5 more authors.
PLoS ONE | Year: 2010

We present results of two intensive mark-release-recapture surveys conducted during the wet and dry seasons of 2008 in the villages of Fourda and Kenieroba, Mali. The former is a small fishing village by the Niger River with a moderate to high densities of Anopheles gambiae Giles s.s. (Diptera: Culicidae) throughout the year, while the latter is a large agricultural community 2 km inland that experiences strong seasonal fluctuation in An. gambiae densities. We estimate the population size of female An. gambiae in Fourda to be in less than 3,000 during the dry season. We found evidence of large population size and migration from Fourda in Kenieroba during the wet season, but very low numbers and no sign of migrants during the dry season. We suggest that malaria vector control measures aimed at adult mosquitoes might be made more efficient in this region and other seasonal riparian habitats by targeting disruption of mosquito populations by the river during the dry season. This would decrease the size of an already small population, and would be likely to delay the explosive growth in vector numbers in the larger inland villages as rainfall increases. Source

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