Over the last decades agroforestry parklands in Burkina Faso have come under increasing demographic as well as climatic pressures, which are threatening indigenous tree species that contribute substantially to income generation and nutrition in rural households. Analyzing the threats as well as the species vulnerability to them is fundamental for priority setting in conservation planning. Guided by literature and local experts we selected 16 important food tree species (Acacia macrostachya, Acacia senegal, Adansonia digitata, Annona senegalensis, Balanites aegyptiaca, Bombax costatum, Boscia senegalensis, Detarium microcarpum, Lannea microcarpa, Parkia biglobosa, Sclerocarya birrea, Strychnos spinosa, Tamarindus indica, Vitellaria paradoxa, Ximenia americana, Ziziphus mauritiana) and six key threats to them (overexploitation, overgrazing, fire, cotton production, mining and climate change). We developed a species-specific and spatially explicit approach combining freely accessible datasets, species distribution models (SDMs), climate models and expert survey results to predict, at fine scale, where these threats are likely to have the greatest impact. We find that all species face serious threats throughout much of their distribution in Burkina Faso and that climate change is predicted to be the most prevalent threat in the long term, whereas overexploitation and cotton production are the most important short-term threats. Tree populations growing in areas designated as ‘highly threatened’ due to climate change should be used as seed sources for ex situ conservation and planting in areas where future climate is predicting suitable habitats. Assisted regeneration is suggested for populations in areas where suitable habitat under future climate conditions coincides with high threat levels due to short-term threats. In the case of Vitellaria paradoxa, we suggest collecting seed along the northern margins of its distribution and considering assisted regeneration in the central part where the current threat level is high due to overexploitation. In the same way, population-specific recommendations can be derived from the individual and combined threat maps of the other 15 food tree species. The approach can be easily transferred to other countries and can be used to analyze general and species specific threats at finer and more local as well as at broader (continental) scales in order to plan more selective and efficient conservation actions in time. The concept can be applied anywhere as long as appropriate spatial data are available as well as knowledgeable experts.

The Shea tree (Vitellaria paradoxa) is a major tree species in African agroforestry systems. Butter extracted from its nuts offers an opportunity for sustainable development in Sudanian countries and an attractive potential for the food and cosmetics industries. The purpose of this study was to develop near-infrared spectroscopy (NIRS) calibrations to characterize Shea nut fat profiles. Powders prepared from nuts collected from 624 trees in five African countries (Senegal, Mali, Burkina Faso, Ghana and Uganda) were analyzed for moisture content, fat content using solvent extraction, and fatty acid profiles using gas chromatography. Results confirmed the differences between East and West African Shea nut fat composition: eastern nuts had significantly higher fat and oleic acid contents. Near infrared reflectance spectra were recorded for each sample. Ten percent of the samples were randomly selected for validation and the remaining samples used for calibration. For each constituent, calibration equations were developed using modified partial least squares (MPLS) regression. The equation performances were evaluated using the ratio performance to deviation (RPD(p)) and R(p)(2) parameters, obtained by comparison of the validation set NIR predictions and corresponding laboratory values. Moisture (RPD(p) = 4.45; R(p)(2) = 0.95) and fat (RPD(p) = 5.6; R(p)(2) = 0.97) calibrations enabled accurate determination of these traits. NIR models for stearic (RPD(p) = 6.26; R(p)(2) = 0.98) and oleic (RPD(p) = 7.91; R(p)(2) = 0.99) acids were highly efficient and enabled sharp characterization of these two major Shea butter fatty acids. This study demonstrated the ability of near-infrared spectroscopy for high-throughput phenotyping of Shea nuts.

Article original Fruit production of sheanut tree (Vitellaria paradoxa Gaertn. C.F., Sapotaceae), in traditional agroforestry parklands in Burkina Faso. Abstract-Introduction. Our study aimed at comparing fruit production of sheanut trees located in agroforestry parklands to those present in natural formations. Materials and methods. The fruiting status of sheanut trees was assessed in 2002 using a systematic survey method with three transects established across two forest stand types: an agroforestry parkland and a natural formation. This survey allowed the collection of 10 fruits per tree, which were measured and weighed. The dried kernel yield was assessed on a sample of 25 trees from both forest stand types. Results. We found that 94% of trees located in agroforestry parklands produced fruits while only 56% of trees located in natural formations did so. The kernel average yield of trees located in agroforestry parklands, around 4 kg•tree-1 , was statistically higher than that of trees located in natural formations (close to 1.5 kg•tree-1). Significant differences were also found between the mean fruit length (3.7 cm against 2.9 cm) and width (3.0 cm against 2.3 cm) of the trees located in the two forest stand types sampled. The average weight of an individual dried kernel of trees located in agroforestry parklands (about 4.5 g) was statistically higher than the average weight of a kernel from trees located in natural formations (2.6 g). Discussion and conclusion. Sheanut trees located in agroforestry parklands can therefore be considered as "plus-trees" compared with those present in natural formations. Burkina Faso / Vitellaria paradoxa / cropping systems / natural forests / agroforestry / production possibilities / fruits / almonds Productivité fruitière du karité (Vitellaria paradoxa Gaertn. C. F., Sapotaceae) dans les parcs agroforestiers traditionnels au Burkina Faso. Résumé-Introduction. Notre étude a eu pour objectif de comparer la production fruitière des karités de parcs agroforestiers à celle d'arbres présents dans les formations naturelles. Matériel et méthodes. La production fruitière de karités a été évaluée à l'aide d'un inventaire systématique effectué en 2002 sur trois transects établis à cheval sur deux types de peuplements : un parc agroforestier et une formation naturelle. Cet inventaire a permis de prélever dix fruits par arbre, qui ont été mesurés et pesés. Le rendement en amandes sèches a été évalué sur la production de deux lots de 25 arbres localisés l'un dans un parc agroforestier et l'autre dans une formation naturelle. Résultats. Nos résultats ont montré que 94 % des arbres des parcs agroforestiers avaient fructifié pendant la période d'étude contre 56 % des arbres présents dans les formations naturelles. Le rendement moyen en amandes des arbres des parcs, d'environ 4 kg•arbre-1 , a été statistiquement supérieur à celui des arbres des formations naturelles (1,5 kg•arbre-1 environ). Il en a été de même pour les longueurs moyennes (3,7 cm contre 2,9 cm) et les largeurs moyennes (3,0 c...