Influence des haies de Jatropha sur le rendement d’une culture de sorgho (Sorghum vulgare) dans la zone Ouest du Burkina Faso: cas du terroir de Torokoro

Dans un contexte de désertification et avec la crise énergétique, un bon nombre d’acteurs de développement au Burkina Faso s’est intéressé au Jatropha curcas L. comme source d’énergie et de durabilité des productions. Afin d’évaluer l’influence de Jatropha sur les propriétés chimiques du sol et la productivité du sorgho associée, des essais ont été suivis pendant trois ans dans le terroir de Torokoro en zone Sud soudanienne de pluviométrie d’environ 1200 mm. Les plants de Jatropha, âgés de 6 ans, sont plantés aux écartements de 5 m entre les lignes et 2 m entre les plants. Le dispositif expérimental comporte trois blocs composés chacun de deux parcelles de 400 m2 correspondants aux 2 traitements: une par celle avec l’association sorgho-Jatropha et une parcelle en culture pure de sorgho (témoin). Les prélèvements de sol ont été effectués sous houppier, à 1 m et2m de la haie. Les résultats indiquent que Jatropha améliore la teneur du sol en carbone de 10% et de 8% en matière organique par rapport au témoin. Jatropha est aussi source de phosphore et de potassium et influence positivement la productivité du sorgho. Jatropha améliore donc les propriétés chimiques du sol et la productivité du sorgho.© 2015 International Formulae Group. All rights reserved.Mots clés: Jatropha curcas L., sol, Sorgho, Rendements, propriétés chimiques, Burkina FasoEnglish Title: Influence of Jatropha hedges on the yield of a sorghum crop (Sorghum vulgare) in the western region of Burkina Faso: case of Torokoro localityEnglish AbstractIn a context of desertification and with the energy crisis, a number of development actors in Burkina Faso became interested in Jatropha curcas L. as a source of energy and sustainability of production. To assess the influence of Jatropha on soil chemical properties and on the productivity of associated sorghum, experiments were followed for three years in the village of Torokoro in south sudanian region, with a rainfall of about 1200 mm. Jatropha plants, aged 6, are planted at 5 m between rows and 2 m between plants. The experiment consisted of three blocks each consisting of two plots of 400 m2 corresponding to two treatments: a plot with sorghum and Jatropha in association and a plot with sorghum only (control). Soil samples were taken under crown, at 1m and 2 m from the hedge. The results indicate that Jatropha improves the carbon content in the soil of 10%, and the organic matter content of 8% compared to the control. Jatropha is also a source of phosphorus and potassium and positively influences the productivity of sorghum. Therefore, Jatropha improves the chemical properties of soil and productivity of sorghum.© 2015 International Formulae Group. All rights reserved.Keywords: Jatropha curcas L., soil, Sorghum, yields, chemical properties, Burkina Fas

Characterizing sorghum ( Sorghum bicolor [L.] Moench) varieties diversity to identify those with contrasting traits of interest for intercropping systems in the Sudano-Sahelian zone of West Africa

Early accessInternational audienceSorghum is an important staple crop in Sub-Saharan Africa. In the Sudano-Sahelian zone of West Africa, sorghum is mainly intercropped with cowpea, but these intercropping systems are facing low-productivity problems. The overall aim of this research was to identify sorghum varieties with different agro-morphological and physiological traits that could improve the performance of the intercropping systems. We followed a two-step methodology comprising (i) identification of varieties and plant traits of interest in intercropping systems, using participatory methods, and (ii) agro-morpho-physiological characterization of 50 sorghum varieties, to examine the range of variation in traits of interest. The results show that landraces are the varieties most widely used by farmers, and that 82.5% of farmers consider the variety type they choose for intercropping to be important. Farmers mentioned plant height, number of leaves and stem diameter as important traits to consider. Analysis of variance showed significant differences between varieties for half of the 24 agro-morpho-physiological traits studied. Hierarchical clustering identified three main groups of varieties, distinguished by morphological traits such as stem diameter, total number and size of leaves (group 1), root traits (depth, growth angle, dry matter) and relative chlorophyll content (groups 2 and 3). Based on this classification, we recommend several varieties from each of the three groups, exhibiting contrasting traits, for an assessment of their performances in intercropping systems