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Background Environmental heterogeneity, emerging pathogens and limited access to financial and agricultural inputs prevent farmers from producing consistent crop yields in many developing countries. Yield instability impedes establishment of processing and export industries, thereby inhibiting economic development. Modern varieties offer significant increases in yield stability. Results A deeply collaborative, multi-national germplasm trialing network was established in West Africa to identify tomato varieties well adapted to each country and mobilize those varieties into local seed distribution networks alongside an integrated pest management program. Research partners in seven West African countries evaluated over 100 tomato varieties for resistance to tomato leaf curl disease (ToLCD). Using biotechnology, the identity and distribution of the key viruses (begomoviruses) causing ToLCD in these countries were identified, and a vector-independent inoculation method (agroinoculation) was developed. The trials identified a set of high-performing varieties with resistance. Agroinoculation with the three prevalent begomoviruses confirmed resistance. Conclusions These trial results fulfill the new Economic Community of West African States harmonized seed regulation policy, which requires at least 2 years of national performance trials prior to commercialization of a tomato variety. To compete with a rapidly expanding canned tomato import industry, West African growers need to increase productivity and processing capacity; therefore, we also assessed processing and export trade data for fresh and processed tomatoes from each of the seven countries.

Five batches of Bolivian Schinus molle essential oils were obtained from pilot and industrial-scale hydrodiffusions. They were analyzed by gas chromatography to find 80 known compounds and two unknown molecules. In particular, preisocalamendiol (5.6-11.0 %) was found to be an important constituent of these oils, along with shyobunol (0.6-3.2 %) and several other related oxygenated sesquiterpenes. These compounds, usually found in Acorus calamus, had not been reported altogether in S. molle essential oils previously. These findings, in light of the GABAA positive modulating effect of shyobunone and preisocalamendiol, along with some traditional uses of S. molle, suggest that further investigation of the tranquilizing properties of these Bolivian oils would be of interest.

Depuis quelques annees, on assiste au Mali a une augmentation de la production maraichere et de la culture de manioc au cours de la saison seche. Traditionnellement, ces cultures sont protegees des animaux d’elevage, qui divaguent librement a cette epoque de l’annee, par des clotures faites de branches epineuses collectees sur divers arbres, les haies mortes. Pour diminuer la pression que ce prelevement entraine sur les arbres du terroir, certains proposent l’utilisation par les paysans de la haie vive amelioree, une cloture d’arbres vivants, generalement epineux, plantes a tres faible espacement. Diverses contraintes limitent toutefois l’adoption de cette technique par les paysans. Une etude a donc ete realisee dans le Cercle de Segou, afin de caracteriser les Unites de production agricole (UPA) utilisant une haie vive amelioree et d’identifier les facteurs determinant son adoption. Les UPA utilisant une haie vive amelioree possedent generalement plus de main-d’œuvre, plus de materiel agricole et un cheptel animal plus important que les UPA non utilisatrices. Le fait que les UPA utilisatrices de la haie vive amelioree fassent partie des UPA les mieux nanties souleve des interrogations quant a son accessibilite aux paysans les plus demunis. Les resultats indiquent par ailleurs que l’utilisation de la technique est determinee par des variables liees a l’information et a la formation des paysans.

Market-oriented production of gardening crops and cassava (Manihot utilissima) in the dry season is an increasingly frequent practice in Segou, Mali. Traditionally, these crops are protected from roaming livestock with the help of dead fences. In order to provide a sustainable alternative to dead fences, the International Centre for Research in Agroforestry (ICRAF) began promoting the use of live fences, living trees planted closely together around a field plot. This study was conducted with the first farmers to use these live fences. These farmers expressed satisfaction with the protection offered by the trees and their ability to provide a variety of medicinal, economic, and food products. The form of land tenure, the social status of farmers within their families, and the availability of labour seem to be important factors in the decision to test the live fence. This raises questions about the accessibility of this technique and its possible contribution to the social and economic differentiation of its users.

Shifting slash-and-burn agriculture is likely one of the main causes of forest degradation in southern Belize. Although many development projects have attempted to reduce the impacts of agriculture on the tropical rainforest, the situation is still a cause for concern. A study of the farming system of the San Jose Maya community was therefore carried out to examine agricultural production in its social, cultural, economic, and political context. Results demonstrate that agricultural production contributes to forest degradation because of the limited availability of agricultural land, the low level of investment in agricultural production, the land tenure system, limited marketing opportunities, and the exclusion of Mayas from the country's political and economic domains. Agroforestry could, however, offer a partial solution to the problem of forest degradation. Three types of traditional agroforestry systems are practised in San Jose: the milpa (a slash-and-burn agriculture system), cacao (Theobroma cacao) cultivation under shade trees, and the homegarden. These traditional agroforestry systems almost entirely meet a family's needs for food and wood, and generate at least 62% of family income. Improving the productivity of these systems could help to reduce pressure on the forest in southern Belize.

Five batches of Bolivian Schinus molle essential oils were obtained from pilot and industrial-scale hydrodiffusions. They were analyzed by gas chromatography to find 80 known compounds and two unknown molecules. In particular, preisocalamendiol (5.6–11.0 %) was found to be an important constituent of these oils, along with shyobunol (0.6–3.2 %) and several other related oxygenated sesquiterpenes. These compounds, usually found in Acorus calamus, had not been reported altogether in S. molle essential oils previously. These findings, in light of the GABAA positive modulating effect of shyobunone and preisocalamendiol, along with some traditional uses of S. molle, suggest that further investigation of the tranquilizing properties of these Bolivian oils would be of interest.

International audience; After a long history of opposition, urban agriculture was gradually accepted as a solution to food shortages caused by adverse economic and climatic events in West Africa. In the last two decades, vegetable production has become increasingly important in many West African capitals. It is the main source of income for an estimated 1000 to 3000 producers per capital, and benefits people all along the supply chain. In Dakar, for example, urban production supplies 60% of all vegetables consumed in the city, and 15000 people are estimated to benefit indirectly from vegetable production. Produce includes exotic vegetables (e.g. tomato, sweet pepper, carrot, lettuce, and cabbage) grown in every country and indigenous vegetables (preference being given to leafy indigenous vegetables in the humid tropical countries, and to fruits of indigenous vegetables in the Sahelian countries). In spite of the multiple benefits, many concerns continue to be raised about the quality of vegetables produced in and around the cities. Producers frequently use banned or inappropriate pesticides in excessive quantities, and also polluted irrigation water, wastewater, and untreated sewage sludge. These problems are exacerbated by the lack of enforcement of environmental legislation from local authorities and lack of support given to farmers (in the form of credit, secure tenure, extension services, etc.). This paper reviews available literature on the characteristics of urban vegetable production systems (e.g. types of crops grown, scale of production, farming constraints, health risks, etc.) from six West African countries. By contrasting the case studies set within the context of their respective urban policy environments, the paper seeks to provide an up-to-date evaluation of the potential of urban vegetable production for a modern West African city, highlighting priority areas for research and development.