The mango tree in central and northern Benin: cultivar inventory, yield assessment, infested stages and loss due to fruit flies (Diptera Tephritidae).Abstract --Introduction. The mango tree is of prime importance to the rural economy of central and northern Benin since it provides food and crucial nutriments at the end of the dry season. However, mango producers in Benin are confronted with two problems that are closely connected: deterioration of fruit quality by fruit flies and the inadequacy of postharvest methods. In the Sudanian zone of Benin, fruit flies (Diptera Tephritidae) are highly responsible for major production losses. Materials and methods. An inventory of all present cultivars and yields of main mango cvs. (Gouverneur, Eldon, Dabshar, Kent, Smith, Keitt and Brooks) was carried out in Benin on 7 000 fruits near Parakou (Borgou) during the years 2005 and 2006. Sampling of 3 000 young fruits (length range 13-26 mm) was carried out in 2006 in order to detect some very early tephritid attacks. A loss assessment of pre-ripening and ripening fruits was also carried out on 7 750 fruits in 2006. Results and discussion. We identified 29 cultivars in the district of Borgou where 75% of the mango orchards of Benin are situated. Most of these use the 'gatherer' production system. The early Gouverneur cultivar had the lowest yield (1.8 t·ha -1 ), and the late Brooks cultivar had the highest yield (10.4 t·ha -1 ). Small and immature young fruits allowed development of both C. cosyra and B. invadens in February and March, i.e., before the mango season itself: this result could be a useful result for pest control. For the pre-ripening and ripening stages, average losses due to tephritid varied from 0.34 t·ha -1 to 6.5 t·ha -1 depending on cultivar type, resulting in considerable loss of income for small planters. Taking all cultivars together, losses stood at 17% in early April and exceeded 70% at mid-June. By the middle of the crop year, over 50% losses were recorded. The seasonal cultivar Eldon and late cultivars (Keitt and Brooks) were the most infested. Conclusion. In the Sudanian zone of Benin, the two main species of Tephritidae that have a high economic impact on mango trees are B. invadens and C. cosyra. Our preliminary observations and calculations will be used in a forthcoming article to calculate the economic injury level of these fruit flies. Benin / Mangifera indica / plant developmental stages / Tephritidae / Bactrocera invadens / Ceratitis cosyra / varieties / yields / insect stings / crop losses Le manguier dans le centre et le nord du Bénin : inventaire des cultivars, estimation des rendements, stades touchés et pertes dues aux mouches des fruits (Diptera Tephritidae).Résumé --Introduction. Le manguier occupe une place particulièrement importante dans l'économie rurale des zones centrales et septentrionales du Bénin. Pendant la fin de la saison sèche, la mangue constitue un apport nutritionnel fondamental par sa forte teneur en nutriments. Mais, au Bénin, les producteurs de mangues sont confronté...

Les nouveaux modes d'organisation des processus d'innovation

Farmers are experiencing the need to adapt to climate change, and are developing different strategies. This article contributes to the understanding of farmers' adaptation choices, their determinants and their implications, in relation to the household income. In 2014, Focus Group Discussions (FGDs) and 220 household surveys were carried out with farmers in coffee and food crop zones in Central Kenya. The Heckman model was used to evaluate the determinants of adaptation choices and their marginal effect. Farmers from the coffee zone or from the food crop zone perceive and adapt differently to climate change. Farmers who are aware of changes in climate are more willing to explore adaptation strategies. A positive relationship is found between adaptation to climate change and household income. The highest payoff/return is achieved if multiple adaptation choices are used rather than a single strategy. The choices of strategies are also determined by household characteristics, resource endowment, institutional variables, and climate information. The strong correlation between socio-institutional variables and adaptation capacity suggests the need for the establishment and strengthening of local institutions, such as micro-finance and extension. Résumé -Perception des changements climatiques et choix d'adaptation des agriculteurs du Kenya central. Les agriculteurs doivent s'adapter au changement climatique et développent pour cela différentes stratégies. Cet article contribue à la compréhension des choix d'adaptation des agriculteurs, de leurs déterminants et implications, en lien avec le revenu des ménages. Des groupes de discussion et des enquêtes ont été menés en 2014 auprès de 220 producteurs de zones caféières et de zones de cultures vivrières dans le centre du Kenya. Le modèle d'Heckman a été utilisé pour évaluer les déterminants des choix d'adaptation et leurs effets marginaux. Les producteurs de la zone caféière et de la zone de cultures vivrières perçoivent et s'adaptent différemment au changement climatique. Les agriculteurs qui sont conscients du changement climatique sont plus disposés à explorer différentes stratégies d'adaptation. Une corrélation positive est identifiée entre l'adaptation au changement climatique et l'augmentation du revenu des ménages. Des choix d'adaptation multiples sont plus payants que le choix d'une seule stratégie. Les stratégies d'adaptation sont aussi déterminées par les caractéristiques des ménages, les dotations en ressources, les variables institutionnelles et l'information relative au climat. La forte corrélation entre les variables socio-institutionnelles et les capacités d'adaptation suggère le besoin de renforcer les institutions locales de microfinance et de conseil technique.

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This article examines how research on the agriculture and agrifood systems mobilizes the concept of Innovation System (IS). A literature review on the IS provides an analytical framework for determining its theoretical frame of reference, its area of application and its uses. Based on this framework, a bibliometric analysis of international journals on innovation and agriculture reveals the existence of four knowledge communities, each of which addresses a specific angle of how the IS concept is applied to deal with the specific dimensions of innovation in the agricultural / agrifood sector. The current challenge is to promote exchanges between these communities, particularly between the one that applies an evolutionary approach and the epistemic community, which seeks to build its own concepts originating from the farming system approach and rural sociology. (Résumé d'auteur