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Climate change and variability are significant challenges for the environment and food security worldwide. Development strategies focusing simultaneously on adaptive farming, productivity, and reducing greenhouse gas (GHG) emissions-known as climate-smart agriculture (CSA) strategies-are key to responding to these challenges. For almost a decade, within the framework of Climate Change, Agriculture and Food Security (CCAFS), World Agroforestry (ICRAF), and its partners have been using Participatory Action Research (PAR) to fully engage key stakeholders in co-creating such CSA development strategies. This includes the testing of Agricultural Research for Development (AR4D) CSA scalability options. The multidisciplinary teams include the National Research and Extension Systems (NARES), national meteorological services (NMS), non-profit organizations (NGOs), and local radio programs, among others. The CCAFS-West Africa Program,World Agroforestry-West and Central Africa (ICRAF-WCA), International Union for Conservation of Nature (IUCN), University of Reading, and Centre Regional de Formation et d’Application en Agro-meteorologie et Hydrologie Operationnelle (AGRHYMET) provide technical backstopping to the national teams. Climate information (CI) was used as an entry point to inform the development of CSA technologies and practices within Climate-Smart Villages (CSV). This groundwork has led to a greater understanding of three critical factors for successful CSV implementation: (1) Building strong partnerships to co-design and develop agricultural systems that improve ecosystemand population resilience, (2) Key stakeholders (researchers, farmers, development agents, and students) capacity strengthening through vocational and academic training, and (3) Using CI for livelihood planning at all scales. These three factors support more effective identification and testing of agricultural technologies and practices addressing climate variability and change at plot, community, and landscape levels. This paper discusses the PAR-CSA methodology and parameters for evaluation, including biophysical and social change. Keys to success, including communication, knowledge sharing tools, and scalability are also discussed. Finally, future opportunities for improvement are presented, including knowledge product development, CSA policy and investment planning, capacity building, further engagement of the private sector, and additional research on existing practices and tools.

Recently, a new approach to extension and climate information services, namely Participatory Integrated Climate Services for Agriculture (PICSA) has been developed. PICSA makes use of historical climate records, participatory decision-making tools and forecasts to help farmers identify and better plan livelihood options that are suited to local climate features and farmers’ own circumstances. This approach was implemented in 2016 in two sites in Senegal and Mali, with 57 and 47 farmers, respectively. At the end of the growing season, these farmers were surveyed to explore their perceptions on the use of the approach. In Senegal and Mali, respectively 97% and 76% of the respondents found the approach ‘very useful’. The approach enabled farmers to make strategic plans long before the season, based on their improved knowledge of local climate features. Moreover, evidence demonstrates that PICSA stimulated farmers to consider and then implement a range of innovations which included: (i) changes in timing of activities such as sowing dates, (ii) implementing soil and water management practices, (iii) selection of crop varieties, (iv) fertiliser management and (v) adaptation of plans for the season (farm size, etc.) to the actual resources available to them. The study also demonstrated the potential of farmer-to-farmer extension in scaling up the approach, which is of great interest especially in the current context of limited extension services in the West African region. Keywords: Climate change, Climate information services, Climate variability, Food security, Livelihood options, West Africa

This study focused on leaf and root density dynamics of the most dominant tree species (Vitellaria paradoxa) of West African savannas in two land use types (farmed land and forest). Ten trees located at least 100 m from each other were selected, with five trees each located in the field and in the forest. Five of the trees were of small-diameter [two in the fields (diameter at breast height or DBH 20.1–20.7 cm) and three in the forest (DBH 7.0–8.0–10.8 cm)] and five others were of large-diameter [three in the fields (DBH 38.2–81.8–81.9 cm) and two in the forest (DBH 20.1–20.7 cm)]. One near-vertical rhizotron was installed under each tree to evaluate root density while canopy openness, diffuse and directly transmitted light were monitored by taking hemispheric photograph monthly. After a two-year period of monitoring, the results revealed a strong seasonality in root density with peak root density observed during the rainy season in August and the lowest production during the dry season in April. Significant lowest canopy openness was observed from August to September while the highest occurred from March to May, which was found to be synchronous with fine root dynamics. The light interception followed the same trends as the leaf production. Furthermore, both mature and young trees showed significant higher root density in the fields compared to the forest while the mean values of all the parameters of canopy openness and light transmittance were higher in the forest than the fields.

Pterocarpus santalinoides is a multipurpose tree species, native to Africa and South America. However, excessive pruning for fodder is jeopardising its seed production leading to poor regeneration in the Sahel region. Efficient vegetative propagation techniques may overcome this concern. To address this issue, four experiments were conducted to determine the effects of substrate (Experiment 1), cutting type (Experiments 2 and 3), genotype (Experiment 4) and auxins (Experiments 1, 2, and 4) on rooting ability in a non-mist propagating unit in Mali. Among the four tested substrates, no significant differences were found in rooting parameters, including the percentage of rooted cuttings, the number of roots and secondary roots per rooted cutting, and the length of the longest root per rooted cutting. Semi-hardwood cuttings rooted significantly better than softwood cuttings with a higher percentage of rooted cuttings (31.7 ± 6.5% vs. 9.2 ± 2.7%), greater number of roots (8.2 ± 4.8 vs 1.5 ± 0.7), greater numbe...

In the Sahel region, many woody species are used as fodder because of their high nitrogen content, especially during the dry season, in contrast to grasses and crop residues. Unfortunately, this resource is being threatened by regular pruning, increasing livestock browsing and impeding their natural regeneration. Therefore, there is a need to find appropriate regeneration options to sustain fodder production. Thus, a series of vegetative propagation experiments were conducted to identify the most appropriate multiplication methods of some of the species used as fodder. This series included testing the effects of naphthalene acetic acid (NAA) and indole butyric acid (IBA) on rooting ability of stem cuttings of 12 species: Afzelia africana, Balanites aegyptiaca, Bauhinia rufescens, Commiphora africana, Faidherbia albida, Ficus gnaphalocarpa, Guiera senegalensis, Kigelia africana, Pterocarpus erinaceus, Pterocarpus lucens, Pterocarpus santalinoides and Terminalia avicennioides. The series also evaluated the impacts of the size (a. africanantalinoides was revealed to be an easy-to-root species, showing a high percentage of rooted cuttings (up to 88 ± 3%), followed by P. erinaceus, P. lucens and B. aegyptiaca (up to 37 ± 4%, 31 ± 5% and 26 ± 6%, respectively), in contrast to A. africana, cuttings of which did not root at all. The application of NAA and IBA enhanced the number of roots and secondary roots per rooted cutting. Large-diameter cuttings (15–20 mm) of deeply planted C. africana gave the highest percentage of rooted cuttings (78.3 ± 4.4%). Tree pruning improved the rooting capacity of cuttings collected from P. erinaceus with one-month resprouts giving the highest percentage of rooted cuttings (50.0 ± 6.7%). These results indicate that P. santalinoides, C. africana, P. erinaceus, P. lucens and B. aegyptiaca are amenable to vegetative propagation as an alternative to sexual propagation.Keywords: auxin, clonal propagation, forage, non-mist propagator, rooting ability

Combination of poor soil fertility and climate change and variability is the biggest obstacle to agricultural productivity in Sub-Saharan Africa. While each of these factors requires different promising adaptive and climate-resilient options, it is important to be able to disaggregate their effects. This can be accomplished with ordinary agronomic trials for soil fertility and climate year-to-year variability, but not for long-term climate change effects. In turn, by using climate historical records and scenario outputs from climate models to run dynamic models for crop growth and yield, it is possible to test the performance of crop management options in the past but also anticipate their performance under future climate change or variability. Nowadays, the overwhelming importance given to the use of crop models is motivated by the need of predicting crop production under future climate change, and outputs from running crop models may serve for devising climate risk adaptation strategies. In this study we predicted yield of one maize variety named Massongo for the time periods 1980–2010 (historical) and 2021–2050 (2030s, near future) across agronomic practices including the fertilizer input rates recommended by the national extension services (28 kg N, 20 kg P, and 13 kg K ha−1). The performance of the crop model DSSAT 4.6 for maize was first evaluated using on-farm experimental data that encompassed two seasons in the Sudano-Sahelian zone in six contrasting sites of Central West Burkina Faso. The efficiency of the crop model was evidenced by reliable simulations of total aboveground biomass and yields after calibration and validation. The root-mean-square error (RMSE) of the entire dataset for grain yield was 643 kg ha−1 and 2010 kg ha−1 for total aboveground biomass. Three regional climate change projections for Central West Burkina Faso indicate a decrease in rainfall during the growing period of maize. All the three scenarios project that the decrease in rainfall is to the tune of 3–9% in the 2030s under RCP4.5 in contrast to climate scenarios produced by the regional climate model GCM ICHEC-EC-Earth which predicted an increase of rainfall of 25% under RCP8.5. Simulations using the CERES-DSSAT model reveal that maize yields without fertilizer show the same trend as with fertilizer in response to climate change projections across RCPs. Under RCP4.5 with output from the climate model ICHEC-EC-Earth, yield can slightly increase compared to the historical baseline on average by less than 5%. In contrast, under RCP8.5, yield is increased by 13–22% with the two other climate models in fertilized and non-fertilized plots, respectively. Nevertheless, the average maize yield will stay below 2000 kg ha−1 under non-fertilized plots in RCP4.5 and with recommended mineral fertilizer rates regardless of the RCP scenarios produced by ICHEC-EC-Earth. Giving the fact that soil fertility improvement alone cannot compensate for the adverse impact of future climate on agricultural production particularly in case of high rainfall predicted by ICHEC-EC-Earth, it is recommended to combine various agricultural techniques and practices to improve uptake of nitrogen and to reduce nitrogen leaching such as the splitting of fertilizer applications, low-release nitrogen fertilizers, agroforestry, and any other soil and water conservation practices.

Within- and between-provenance variations in seed and seedling traits of Khaya senegalensis A. Juss were studied at INERA in Burkina Faso. Nursery grown seedlings from four provenances in Burkina Faso were used for the study. The studies revealed significant variability in all traits evaluated. Seed length and weight significantly varied among provenances and families within provenances, where Bopiel and Koyenga had the highest mean values. Height and root collar diameter of 1 year old seedlings significantly varied among families within provenances. Except leaf biomass ratio and carbon isotope ratio which varied significantly among provenances but not among families within provenances, all other seedling biomass traits—total plant biomass, stem biomass ratio, leaf biomass ratio, root biomass ratio, root shoot ratio, specific leaf area, and leaf area ratio were significantly affected by provenances and families within provenances. The magnitude of variation due to family effect ranged from 65 to 93 % for seed size traits, and from 4.5 to 17.8 % for seedling characters. Estimates of family heritability were moderate to high (0.67–0.95) for seed traits, but low to moderate (0.19–0.59) for seedling characters, indicating that much of the total variation in seed traits is due to the genetic effect. The two most prominent provenances, Koyenga and Bopiel, with higher seed size and greater seedling growth could be considered for an eventual K. senegalensis improvement program in Burkina Faso.

An understanding of the proportion of true seedlings, seedling sprouts and root suckers in the forest is essential for directing the genetic composition of the future crop. We conducted a study to determine the difference between these plantlets of Detarium microcarpum based on morphological characters and carbohydrate contents in leaves and roots. For individuals ≤50 cm in height, root suckers had the highest values for height, stem length, internode number, root diameter, rachis length and leaflet number. The concentrations of starch and total nonstructural carbohydrates in the roots of seedling sprouts were superior. Plantlets did not differ in the concentration of leaf carbohydrates. For individuals >50 cm in height, root suckers had larger values for stem length, root diameter, leaflet length and width. Roots of seedling sprouts showed higher concentrations of soluble sugars and total soluble sugars. True seedlings were distinguished from seedling sprouts and root suckers using all morphological traits except collar diameter and leaflet number. Root suckers and seedling sprouts showed a closer morphological resemblance; thus resulted in slightly more than 50% discrimination success. In conclusion, discrimination between seedling sprouts and root suckers appeared to be more difficult than between true seedlings and clonal plantlets. Resume Une bonne comprehension de la proportion de vrais semis, de rejets et de drageons en foret est essentielle pour orienter la composition genetique du peuplement forestier. Nous avons realise une etude pour determiner la difference entre les plantules de Detarium microcarpum en nous basant sur les caracteristiques morphologiques et la concentration en hydrate de carbone des feuilles et des racines. Parmi les individus ≤50 cm de haut, les drageons avaient les valeurs les plus elevees pour la hauteur, la longueur des tiges, le nombre des entrenœuds, le diametre des racines, la longueur du rachis et le nombre de folioles. La concentration d’amidon et le total des hydrates de carbone non structuraux etaient superieurs dans les racines des rejets. La concentration des hydrates de carbone dans les feuilles des plantules ne differait pas. Chez les individus >50 cm de haut, les dragons presentaient des valeurs superieures pour la longueur de la tige, le diametre des racines, la longueur et la largeur des folioles. Les racines des drageons presentaient une plus forte concentration de sucres solubles et du total des sucres solubles. Les semis ont pu etre distingues des rejets et des drageons au moyen de toutes leurs caracteristiques morphologiques sauf le diametre du collet et le nombre de folioles. Les drageons et les rejets montraient une ressemblance morphologique plus grande et n’ont donc permis qu’une discrimination reussie a un peu plus de 50% seulement. En conclusion, la distinction entre rejets et drageons apparait plus difficile a effectuer qu’entre semis et plantules clonees.

Savanna plant species are capable of regenerating both sexually and asexually. The importance of each regeneration mechanism depends on the species, the type and the intensity of disturbance. This paper describes the relative importance of sexual and asexual regeneration for the restoration of a selectively cut savanna woodland in Burkina Faso. Plantlets regenerated sexually or asexually were determined by excavating the below ground system and assessing basal and aerial sprouts within 144 quadrats along transects in 2, 5, 10 year-cut and control plots. The result shows that seedling sprouts were predominant (83%) compared to root sucker (4%), coppice (5%), water sprout (2%) and layering (less than 1%). True seedlings constituted a minor component (5%) of the plantlet population. A total of 54 woody species was found in the plantlet population with 52 presenting seedling sprouts. Twelve species were found regenerating from both seeds and root buds; of which Dichrostachys cinerea, Pteleopsis suberosa and Detarium microcarpum had the highest number of plantlets. Feretia apodanthera was the only layering species encountered in the sampled area. Coppices, root suckers and water sprouts showed higher height and bigger collar diameter compared to seedling sprouts and true seedlings. It can be concluded that sexual reproduction is the dominant mechanism of seedling recruitment in this disturbed savanna-woodland, and that its success relies on the ability of plantlets of seed origin to resprout abundantly.

Khaya senegalensis is an important tree species for timber production, native to West Africa, but mahogany shoot borer attacks prevent successful plantations. This research was aimed at comparing the growth of two propagule types, seedlings and stecklings, of Khaya senegalensis subjected to four irrigation regimes, 25, 50, 75 and 100% field capacity in Burkina Faso. The relative growth rate, biomass allocation and intrinsic water use efficiency of the propagules were assessed in a full-factorial pot experiment in block design. Except the relative growth rate of stem basal diameter and specific leaf area, for which mean values were significantly higher for seedlings than stecklings, the two propagule types had similar growth patterns regarding relative growth rates of stem length, leaf, stem, root and the total plant biomass. There was no significant difference between propagule types concerning biomass fraction to total plant biomass of leaf, stem and root, root to stem ratio, leaf area productivity and carbon isotope ratio (δC). However, the irrigation regimes significantly affected all parameters. In contrast to 75 and 100% field capacity irrigation regimes, the low water supply of 25 and 50% field capacity resulted in plant stress, which was evident from the significant reduction in plant growth and biomass production and an increase in the root biomass to total plant biomass ratio and δC. It can be concluded that seedlings and stecklings have comparable growth patterns, while water stress is a major growth-limiting factor highlighting the need for selecting drought and borer resistant genotypes for successful plantations.1313

Detarium microcarpum is a valuable tree species for fuelwood, timber, food and medicine in sub-Saharan Africa. However, its population is dwindling due to overexploitation, its seedlingsâ low survival rate and slow growth. Vegetative propagation might enhance both survival and growth, but to date a successful clonal method does not exist for D. microcarpum. We conducted four experiments to examine the effects of propagation environment (high versus low humidity), cutting length and diameter, alignment of root segments (horizontal versus vertical) and distance from the root collar of donors on the regeneration ability of root segments collected from field-grown D. microcarpum trees in Burkina Faso. The size of root segments significantly affected their regeneration ability, while alignment had no effect. Sprouting was possible from 10 and 20-cm long segments of 15â60 mm diameter with 7â43% sprouting efficiency and multiple shoots while 5 cm long segments were unsuitable with 0â3% sprouting efficiency. Cuttings maintained at low humidity produced larger diameter sprouts than those in greenhouse. All cuttings showed strong polarity with most of the shoots developing at the proximal end. Rootlings from 20 cm root segments produced more new roots (0.62 ± 0.08 g) than those from 10 cm segments (0.34 ± 0.09 g), but they were similar for sprout and leaf growth. We conclude that lateral roots of field-grown mature trees can be used to produce rootlings in a nursery. Since this study is the first attempt to propagate D. microcarpum from root cuttings, further investigations are required to optimize the technique.