Variabilité morphologique de Balanites aegyptiaca (L.) Del. dans la région du Ouaddaï au Tchad

Dans le Sahel tchadien, le Balanites aegyptiaca est un arbre de grandes importances socioéconomiques pour les populations. L’objectif de l’étude a été de développer les stratégies de conservation et d’utilisation durable des ressources génétiques de l’espèce. Une enquête socio-économique et un inventaire botanique ont été réalisés auprès de 4 groupes ethniques répartis dans 3 villages. Les analyses botaniques ont porté sur 16 descripteurs morphologiques quantitatifs. Les populations locales ont une bonne connaissance de l’espèce et disposent d’un système de classification empirique utilisant des critères communs ou variables selon le groupe ethnique. Les critères communs aux 4 groupes ont été la taille de l’arbre, les dimensions et la forme du fruit, le goût de la pulpe et la taille des feuilles. Le fruit a été de loin le caractère le plus discriminant. Les descripteurs morphologiques discriminants ont été la longueur du grand axe du fruit (p<0,001), la largeur des feuilles (p<0,05) et la hauteur de l’arbre (p<0,05). Trois morphotypes ont été identifié chez l’espèce dont le plus intéressant regroupe des arbres de grande taille, aux feuilles larges et produisant de longs fruits. Ces informations ouvrent de meilleures perspectives pour la sélection variétale et la domestication de cette espèce dans la zone.© 2016 International Formulae Group. All rights reserved.Mots clés: Fruitiers locaux, Balanites aegyptiaca, savoirs endogènes, morphotypes, Ouaddaï, TchadEnglish Title: Morphological variability of Balanites aegyptiaca (L.) Del. in the region of Ouaddaï in ChadEnglish AbstractBalanites aegyptiaca is a tree of high socioeconomic importance for the population who lives in the Sahelian region of Chad. The aim of this study was to develop any strategies of preservation and sustainable use of the genetic resources of the species. Thus, a socioeconomic survey was carried out within four ethnic groups in three villages and botanical inventory was set up for the purpose. The botanical analyses dealt with 16 quantitative morphological descriptors. The targeted communities have a good knowledge of the species and make use of and empirical classification system based on common or variable criteria according to the ethnical groups under study. The common criteria to the 4 groups were the height of the tree, the size and shape of the fruit, the pulp taste and the length of the leaf. The fruit was by far the most discriminating aspect. The discriminating morphological descriptors were the length of the main axis of the fruit (p <0.001), the width of  the leaf (p <0.05) and the height of the tree (p <0.05). Three morphotypes were identified in the breed, the most interesting of which concerns high, wide-leafed and long fruit producing trees. This information paves the way for better prospects as far as the selection of varieties and the domestication of the species in the area are concerned.© 2016 International Formulae Group. All rights reserved.Keywords: Local fruit-trees, Balanites aegyptiaca, endogenous knowledge, morphotypes, Ouaddaï, Cha

Will farmers intend to cultivate Provitamin A genetically modified (GM) cassava in Nigeria? Evidence from a k-means segmentation analysis of beliefs and attitudes

Open Access JournalAnalysis of market segments within a population remains critical to agricultural systems and policy processes for targeting new innovations. Patterns in attitudes and intentions toward cultivating Provitamin A GM cassava are examined through the use of a combination of behavioural theory and k-means cluster analysis method, investigating the interrelationship among various behavioural antecedents. Using a state-level sample of smallholder cassava farmers in Nigeria, this paper identifies three distinct classes of attitude and intention denoted as low opposition, medium opposition and high opposition farmers. It was estimated that only 25% of the surveyed population of farmers was highly opposed to cultivating Provitamin A GM cassava

Innovations technologiques pour l’adaptation et l’atténuation des effets des changements climatiques en Afrique de l’Ouest: Récits paysans.

En Afrique subsaharienne, comme dans d’autres parties du monde, les changements climatiques constituent une menace sans précédent qui af- fecte des millions de populations rurales et urbaines. Ils sont aussi un obstacle à la réalisation des Objectifs du Millénaire pour le Développement (OMD). Le changement climatique affecte l’agriculture et la sécurité alimentaire, tout comme l’agriculture et la gestion des ressources naturelles affectent le système climatique

MAT-762: BUILDING SUSTAINABLE CONTINUOUSLY REINFORCED CONCRETE PAVEMENT USING GFRP BARS: CASE STUDY-HIGHWAY 40 WEST-MONTREAL, CANADA

Continuously reinforced concrete pavement designs (CRCP) are premium pavement designs that are often used on heavily-trafficked roadways and urban corridors. Although CRCP typically is an effective, long-lasting pavement design, it can develop performance problems when the aggregate-interlock load transfer at the transverse cracks is degraded. The prevalence of wide cracks in CRCP has frequently been associated with ruptured steel and significant levels of corrosion. Because of that, there has been recent interest in identifying new reinforcing materials that can prevent or minimize corrosion-related issues in CRCP. Glass fibre-reinforced polymer (GFRP) bars are one product being investigated for use in CRCP in place of traditional steel bars. This paper summarizes the construction details, material properties, early-age behaviour, and preliminary monitoring results of GFRP CRCP after 12 months in service. The project is located westbound HW-40 in Montreal, Qc, Canada, and presents a collaboration between the Ministry of Transportation of Quebec (MTQ) and the University of Sherbrooke. Varieties of sensors were installed in this project in order to monitor the early-age behaviour and the effects of repeated traffic loads and environmental conditions on the performance of CRCP slabs