Food tree species selection for nutrition-sensitive forest landscape restoration in Burkina Faso

Modern food systems push agriculture to focus on a small number of commercial crops, while there is a very large diversity of untapped edible plants that could be used to address food security and nutrition. Poor and monotonous diets are closely linked to the complex burden of multiple forms of malnutrition and dietary risk. In some contexts, such as West Africa, micronutrient deficiency risks are particularly pronounced. Hence, there is an urgent need to provide people with healthy diets supported by sustainable food systems. Within this context, using nutrition-sensitive forest landscape restoration to combat environmental degradation could contribute towards ensuring the year-round availability of nutritious tree-based food

Relative genome size variation in the African agroforestry tree Parkia biglobosa (Fabaceae: Caesalpinioideae) and its relation to geography, population genetics and morphology

Variation in genome size and in chromosome number can be linked to genetic, morphological and ecological characteristics, and thus be taxonomically significant. We screened the relative genome size (RGS) and counted the number of mitotic chromosomes in the African agroforestry tree Parkia biglobosa, a widely distributed savannah species that shows conspicuous morphological clinal variation and strong genetic structure, and tested for linkage of RGS variation to geography, leaf morphology, and population genetic variation. An improved protocol for the preparation of chromosomes was developed. The study is based on 58 individuals from 15 populations covering most of the distribution range of the species. We observed differences in RGS among individuals of up to 10.2 %, with some of the individuals differing statistically in RGS from the bulk of screened individuals. Most of the RGS variation was within populations whereas variation was unrelated to any of the tested features of the species. Those chromosome numbers which could be exactly established were invariable 2n = 2x = 26. In conclusion, there was no evidence from the karyological data for structured intra-specific taxonomic heterogeneity.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Microsatellite Genotypes

Data file contains microsatellite genotypes for the 8 SSRs studied in 1610 individuals from 84 populations - format is Genalex - coordinates of populations are in columns 21 and 22

Data from: Phylogeography of African locust bean (Parkia biglobosa) reveals genetic divergence and spatially structured populations in West and Central Africa

The evolutionary history of African savannah tree species is crucial for the management of their genetic resources. In this study, we investigated the phylogeography of Parkia biglobosa and its modelled distribution under past and present climate conditions. This tree species is very valued and widespread in West Africa, providing edible and medicinal products. A large sample of 1 610 individuals from 84 populations, distributed across 12 countries in Western and Central Africa, were genotyped using eight nuclear microsatellites. Individual-based assignments clearly distinguished three genetic clusters, extreme West Africa (EWA), centre of West Africa CWA), and Central Africa (CA). Overall, estimates of genetic diversity were moderate to high, with lower values for populations in EWA (AR=6.4, HE=0.78 and HO=0.7) and CA (AR=5.9, HE=0.67 and HO=0.61) compared to populations in CWA (AR=7.3, HE=0.79 and HO=0.75). The overall population differentiation was found to be moderate (FST=0.09). A highly significant isolation-by-distance pattern was detected, with a marked phylogeographic signature suggesting possible effects of past climate and geographic barriers to migration. Modelling the potential distribution of the species showed a contraction during the last glaciations followed by expansion events. The exploratory Approximate Bayesian Computation conducted suggests a best-supported scenario in which the cluster CWA traced back to the ancestral populations and a first split between EWA and CWA took place about 160 000 years BP, then a second split divided CA and CWA, about 100 000 years BP. However, our genetic data do not enable to conclusively distinguish among a few alternative possible scenarios

Data from: Phylogeography of African locust bean (Parkia biglobosa) reveals genetic divergence and spatially structured populations in West and Central Africa

The evolutionary history of African savannah tree species is crucial for the management of their genetic resources. In this study, we investigated the phylogeography of Parkia biglobosa and its modelled distribution under past and present climate conditions. This tree species is very valued and widespread in West Africa, providing edible and medicinal products. A large sample of 1 610 individuals from 84 populations, distributed across 12 countries in Western and Central Africa, were genotyped using eight nuclear microsatellites. Individual-based assignments clearly distinguished three genetic clusters, extreme West Africa (EWA), centre of West Africa CWA), and Central Africa (CA). Overall, estimates of genetic diversity were moderate to high, with lower values for populations in EWA (AR=6.4, HE=0.78 and HO=0.7) and CA (AR=5.9, HE=0.67 and HO=0.61) compared to populations in CWA (AR=7.3, HE=0.79 and HO=0.75). The overall population differentiation was found to be moderate (FST=0.09). A highly significant isolation-by-distance pattern was detected, with a marked phylogeographic signature suggesting possible effects of past climate and geographic barriers to migration. Modelling the potential distribution of the species showed a contraction during the last glaciations followed by expansion events. The exploratory Approximate Bayesian Computation conducted suggests a best-supported scenario in which the cluster CWA traced back to the ancestral populations and a first split between EWA and CWA took place about 160 000 years BP, then a second split divided CA and CWA, about 100 000 years BP. However, our genetic data do not enable to conclusively distinguish among a few alternative possible scenarios

Spatially explicit multi-threat assessment of food tree species in Burkina Faso : a fine-scale approach

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