Search

Baobab (Adansonia digitata), arbre « sacré » dont les feuilles, fruits et graines sont utilisés dans la médecine traditionnelle, Sénégal. © IRD/J.-J. Lemasson Le statut des ressources biologiques a particulièrement évolué dans la dernière décennie du xxe siècle. En effet, après une période où les ressources dans leur ensemble étaient considérées comme un bien commun de l’humanité, leur statut a changé au début des années 1990. La Convention sur la diversité biologique (CDB), adoptée le 22 ma...

Introduction Le projet de recherche Fogefo-Plus (Forêts de Guinée forestière – Plantes utiles), mené dans le cadre du programme « Sud Expert Plantes Développement Durable » (SEP2D), a pour objectif principal d’identifier les plantes forestières utiles – hors bois d’œuvre et bois de chauffe – de Guinée forestière, une des régions naturelles de Guinée, et de caractériser leur importance économique pour les populations urbaines et rurales. Durant ce projet (2017-2020), des enquêtes ont été réali...

Dans un monde confronté aux changements climatiques et à des pandémies en lien avec la destruction des milieux naturels, les enjeux liés à la préservation de la biodiversité sont dorénavant bien connus et ont donné lieu à des accords internationaux majeurs, comme le protocole de Nagoya. Dans ce contexte mondial, les recherches menées au Sud sont primordiales. Les contributions rédigées ici par des chercheurs dʼAfrique, de lʼocéan Indien, dʼAsie du Sud-Est et dʼEurope traduisent la vigueur de la recherche sur la biodiversité dans les pays intertropicaux francophones. Documenter la diversité des écosystèmes végétaux locaux, mieux connaître les savoirs traditionnels et les utilisations populaires des plantes ou des champignons, valoriser le rôle des collections botaniques, identifier des chaînes de valorisation économique responsables, gérer durablement les écosystèmes et leurs ressources, élaborer des outils stratégiques pour une gouvernance environnementale basée sur la science et, enfin, montrer la nécessité de lʼimplication citoyenne et de lʼensemble des acteurs concernés, tels sont les grands thèmes déclinés ici. Cet ouvrage collectif intéressera tous ceux qui travaillent sur la biodiversité des écosystèmes intertropicaux. Il souligne la nécessité dʼune science de lʼaction au service du développement durable.

RATIONALE - Arabusta coffee was created by crossing Coffea arabica L. and C. canephora Pierre ex-Froehner after doubling the chromosome number of C. canephora. For breeding studies and coffee quality improvement, clones have been planted in French Guiana. As green bean metabolite content largely influences the coffee cup quality, biochemical and sensory analyses of Robusta and Arabusta were done on green beans and compared as part of Breedcafs H2020 project. METHODS - Arabusta cherries were harvested on 6 clones in 4 farms in Apatou and in Combi research station, and those from Robusta in Combi research station. They were wet processed before grinding. Phenolic compounds and alkaloids were quantified by HPLC (Campa et al, 2017), sucrose by enzymatic analysis (Megazyme kit, Ireland), diterpenes by NMR (Portaluri et al, 2020) and VOC by headspace SPME-GC/ MS (Marie et al, 2020). Lipids were extracted (Folch et al, 1957) and quantified by cgfb (Bordeaux). Sensory analyses followed the protocol guidelines of the Specialty Coffee Association (SCA) for C. arabica (Marie et al, 2020).We used Statistica software for analyses. RESULTS - Compared to Robusta, Arabusta had a lower caffeine content and higher trigonelline, sucrose and fatty acid contents. Arabusta evidenced both 16-O-methylcafestol and kahweol, known markers for Robusta and Arabica species, respectively. 17 of the 25 non-volatile and 23 of the 47 volatile compounds showed significant differences (p≤0.05) between Arabusta and Robusta. Except 5-caffeoylquinate and coumaroylquinate, chlorogenic acids accumulated more in Robusta. A PCA based on volatile compound content separated samples in three groups: Robusta samples, most of the Arabusta from Apatou (richer in pyrazine, toluene, 2-propanone) and those from Combi associated with 3 from Apatou (richer in D-limonene, DMSO, methyl-butanoic acid, and IBMP). A sensory analysis based on 9 sensory parameters indicated that 3 samples received a final score higher than 80. A PCA confirmed that 2 Arabusta samples were particularly different from all the others. CONCLUSIONS & PERSPECTIVES - With higher contents in sucrose, trigonelline, diterpenes, fatty acids and D-limonene and a lower content in caffeine, the composition of the Arabusta green beans seems significantly different from Robusta. The sensory analysis supports the hypothesis that some Arabusta clones possess the potential to produce quality coffee. However, it is necessary to continue the research to confirm these results. This research was funded by BREEDCAFS project, supported by the European Commission under the Horizon 2020 – Research and Innovative Program, H2020-SFS-2016-2, grant agreement number: 727934.

Rational - Benefits of the use of Arabica coffee F1 hybrids in agroforestry (high productivity, cup quality, resistance to drought, pest and diseases) have dominated scientific debates in efforts to promote the use of such hybrids over conventional varieties. However, arabica F1 hybrids are relatively new to most farmers, especially those in the Western highlands of Cameroon, a major arabica coffee growing area, where the plant is mostly grown in association with food and fruit trees. Selecting shade trees is also important for maximising ecosystem services. Methods - From July 2018, a multi-site trial was conducted in six localities of different altitudes (950 to 1,400 m asl) in the western highlands of Cameroon to compare the H1 and Starmaya F1 hybrids with conventional cultivars (Marsellesa and Java). The experiment was laid out in a complete randomised design with eight varietal plots of 12 trees each of the H1, Starmaya hybrid and the control cultivars (Marcellesa and Java). The coffee plants were planted at 3.0 m spacing between rows and 1.5 m spacing between trees along a row, giving a total of 96 coffee plants per variety per site. The study incorporated a semi participatory methodology involving farmers to gain an on-farm assessment of the challenges, environmental feasibility, economic profitability and sociocultural acceptance of Arabica coffee hybrids. Shade tree advice tool, tree inventories and household interviews will be conducted to characterize Arabica coffee farms and farmers ecological knowledge on the provision of ecosystems services by associated shade trees. Results - First phenotyping data showed that the growth of the Starmaya and H1 hybrids variety are earlier and superior to the control varieties Java and Marsellesa. Both hybrids were also more stable and resistant to drought compared to pure line varieties in all altitudes. We also found that the use of shade tree advice tool could guide farmers in selecting appropriate trees that best meet their needs and provide essential ecosystem services. Conclusion & perspectives - Farmers appreciate and support the arabica hybrids due to their fast growth, production and drought resistance. The first true harvest is scheduled for October 2021. A national wide sensitization on Arabica coffee F1 hybrids could create awareness, generate a huge leap in livelihoods as well as get the attention of the government for policy drive. The overall impact of the study could be ensured through implementation of business driven- Agroforestry coffee clusters and innovation platforms.

RATIONALE - Arabusta coffee is an interspecific hybrid derived from C. arabica x C. canephora, often used in coffee breeding to study both the gene transfer from Robusta and its possible use in coffee production. The plants have very different morphological characteristics, as well as different levels of fruit production when compared with the parental species. Arabusta coffee was also studied from a sensory point of view, but in general the literature on this hybrid is rather scarce and the knowledge on it is still fragmentary. From a morphoanatomical point of view, as far as we know, no investigations have been devoted to study Arabusta seed morphology and to disclose possible Arabica-like or Robusta-like traits in its cell structure and this highly stimulated the present work. METHODS - Seed samples of C. arabica L. (Costarica, 2019), C. canephora Pierre ex-Froehner (French Guyana, 2019) and F1 clones of Arabusta coffee (French Guyana, end of 2018) were harvested, properly processed and selected. Seeds were kept in a fixative solution for several days, then rinsed in tap water and cut at -20°C with a cryostat (Leica CM1520). Seed sections of 60 μ in thickness were observed by a Scanning Electron Microscope (Hitachi TM3030plus). Sections of 12 μ in thickness were staining in a Toluidine Blue O solution to highlight the main cell components. Measurements of cell wall area were performed on the electronic images by a Leica Software (Las X). RESULTS ( Arabusta is characterized by an elongated seed, slightly rounded, generally with a linear furrow. The endosperm cells are regular, characterized by a polygonal shape, with not frequent nodes present in their cell wall. Cell wall thickness is not significantly different from the parental species (5,7 ± 1,6 μ). However, the area occupied by the cell wall respect to the cell total area (28%) is more close to that measured in Arabica seeds (29%) than that in Robusta seeds (43%). Optical microscopy observations furtherly put in evidence this tissue aspect, showing similar cell size in Arabusta and Arabica seeds, and smaller cells for Robusta coffee. This feature is probably related to ploidy level (Arabica and Arabusta : 2n = 4x = 44, Robusta 2n = 2x = 22). No histochemical differences in the cell content were observed among the examined coffee species under the chosen experimental conditions. CONCLUSIONS & PERSPECTIVES - The measurements performed on cell wall area and measured diameter as well as cell content area and endosperm cell size show that the morphoanatomical characteristics of Arabusta seeds corresponds more to those of Arabica than Robusta seeds. Further studies are necessary to confirm this preliminary view.

RATIONALE - Until the 80's, arabica coffee was the main commodity crop in Western highlands of Cameroon, but the culture has been almost entirely abandoned after forty years of low coffee prices (Uwizeyimana, 2009). The H2020 BREEDCAFS project ( https://www.breedcafs.eu ) aims at reviving the coffee sector via the introduction of new F1 hybrid coffee varieties well-suited to agroforestry systems, high-yielding and producing a high cup quality. Within this project, this study supports the design of coffee-agroforestry systems matching farmers' needs and adapted to local conditions. METHODS - The study followed the Shade Tree Advice methodology, based on coffee farmers' local ecological knowledge of shade tree species (Van der Wolf et al 2016). Farmers' needs were identified through interviews. Associated shade tree species were listed through on-farm tree species inventories. Shade tree species performances were collected through interviews of farmers and rankings, of which around 100 were assessed in five geographical divisions (Noun, Bamboutous, Menoua, Nde and Grand Mifi) of the West region of Cameroon. RESULTS - The 10 most important criteria for shade tree species selection were: 1) fruit production, 2) coffee fertilizer saving, 3) timber production, 4) production of a third crop beneath shade trees and coffee, 5) impact on coffee yield, 6) reduction of coffee bi-annual production pattern 7) protection of coffee from anthracnose, 8) minimal need for pruning, 9) use in traditional medicine, 10) shading that improves working conditions. Meanwhile, 35 tree species were identified in coffee farms through the inventories, and the resulting agroforestry advices are available online on www.shadetreeadvice.org. CONCLUSIONS & PERSPECTIVES - This study provides a user-friendly tool to support coffee farmers in their selection of shade tree species (Van der Wolf et al, 2016). On a local scale, this tool will contribute to promote the conservation of both economic and indigenous tree species as well as support efforts to revive the coffee sector in Western highlands of Cameroon through the development of sustainable agroforestry practices with the most performant Arabica varieties.

RATIONALE - New coffee hybrids are important for addressing issues of quality, pests & diseases and climate change, but new plant varieties often encounter slow adoption among farmers due to uncertainties and access. Even when coffee hybrids are shown to be more productive and resistant to (a) biotic stresses, less than 5 % of the orchard in Latin America is planted with hybrids each year. A new dissemination strategy is needed, based on access to technology, data and networks, to increase farmer uptake. This is the aim of the H2020 project BREEDCAFS, based on sharing of propagation techniques locally, local assessment of hybrids in agroforestry systems (AFS), and setup of national stakeholder dialog platforms and sustainable agroforestry clusters. Here, we give a first glimpse of the implementation of this new approach. METHODS - For hybrid assessment, on-farm demo-plots with 4 hybrids and a local control were planted in Nicaragua, Costa Rica, Cameroon and Vietnam. Agronomic observations, quality testing, and farmer surveys are carried out to evaluate productivity, profitability and farmer acceptance. Technology for combined somatic embryogenesis (SE) and rooted mini cuttings (RMC) were transferred to partners in Vietnam, Cameroon and Nicaragua, where dialogue platforms have also been created for all stakeholders in the sector. Further, implementation of agroforestry clusters has been initiated with groups of farmers cultivating new hybrids in sustainable AFS, targeted specialty buyers. RESULTS - The combination of SE and RMC is showing to be a lower-cost approach than solely focusing on the complex and expensive method of SE for vegetative propagation of hybrids. The setting-up of rooted mini cuttings nurseries to Vietnam and Cameroon has allowed mass propagation of hybrids locally at reduced costs, while a women's cooperative in Nicaragua now runs a business producing and selling mini-cuttings. Initial field observations are encouraging; in Costa Rica and Nicaragua hybrids are more productive and produce a better coffee quality in AFS, while observations in Vietnam and Cameroon confirmed higher vigour and yield. In Nicaragua, a 1,250 ha agroforestry cluster is already running successfully, delivering high quality coffee to a specialty buyer; a setup that is now being replicated in Vietnam and Cameroon. CONCLUSIONS and PERSPECTIVES - The hybrids assessed in BREEDCAFS show very promising results. As these hybrids are among the first on the market, many innovations are needed to promote their dissemination and adoption. Our approach to disseminate the Arabica hybrids in the coffee belt form a coherent strategy that appears to be effective in addressing replanting new varieties adapted in the coffee sector.

In response to the Nagoya Protocol established to guarantee access to genetic resources and equitable sharing of benefits arising from their use (ABS), the European Commission established a Regulation in 2014. France has adopted the law on biodiversity in 2016, which regulates access to genetic resources taken in France and their use for research and development. The implementation of these regulations concerns all Biological Resource Centers (BRCs), excluding human biological resources. The French Research Infrastructure RARe brings together more than thirty BRCs from INRA, IRD, CIRAD and CNRS research institutes, covering a wide variety of agronomic resources. RARe BRCs, FRB(1) and legal departments of the different research institutes work together on a project funded by IBiSA, a French Infrastructure funding agency for Biology, Health and Agronomy. This project aims to develop new harmonized tools and procedures to help BRCs to work in accordance with regulations of countries of origin of the biological resources. The first task involves legal analysis of the different texts (Nagoya Protocol, EU Regulation, and French laws) to define the consequences according to nature, origin, introduction date, type of use of genetic resources. The second task is to investigate typical cases illustrating collection diversity to propose different scenari for management of collections and tools to implement the Nagoya Protocol. The third task, aims to develop IT (Information Technology) tools that will display the ABS status of each resource, taking into account legislative changes in countries providing resources. These changes will be incremented in real time in the databases of the CRBs. The final task is to raise the awareness of collection managers through the development of dedicated tools and training sessions to ensure conformity of their activities and promote sustainable and equitable use of biodiversity. (1) : Foundation for Research on Biodiversity (www.fondationbiodiversite.fr/en/)

RATIONALE Genome-wide associat10n studies (GW AS) are an efficient approach to dissect the genetic architecture of complex traits. Lipids, including the diterpenes cafestol and kahweol, are key compounds that contribute to the quality of coffee beverages. A genome-wide association study was performed to identify genomic regions associated with lipid, cafestol and kahweol. METHODS Using GBS, we genotyped 107 Cojfea arabica accessions, including wild genotypes from the historical F AO collection from Ethiopia and cultivars. Lipids, cafestol and kahweol contents in green beans were determined by NIRS. For full description of genetic analysis and the four association methods: mrMLM, F ASTmrEMMA, ISIS EM-BLAS SO, pLARmEB see Sant' Ana et al.2018. RESULTS Using the diploid Cojfea canephora genome as a reference for GBS data, we identified 6,696 SNPs. Population structure analyses suggested the presence of two to three groups (K = 2 and K = 3) corresponding to the east and west sides of the Great Rift Valley and an additional group formed by wild accessions collected in western forests. We identified 5 SNPs associated with lipid content, 4 with cafestol, 3 with kahweol and 9 with cafestol/kahweol ratio. Most of these SNPs are near by genes related to metabolic pathways of those compounds. Among all trait-associated SNPs detected by GWAS, three showed strong signals of directional selection between genetic groups identified using STRUCTURE (K = 3). The group with most wild accessions presented very low frequencies of the reference alleles compared with the other two groups. This indicates that domestication and/or breeding process of C. arabica may have changed allelic frequencies of these loci in order to modulate lipids and diterpenes content. CONCLUSIONS & PERSPECTIVES The genetic anaysis helped to define which accessions are more important to preserve in order to have a good genetic representation of the F AO collection and provided insights on C. arabica domestication. The GWAS approach was efficient to identify markers and genomic regions associated to lipids and diterpenes in Coffea arabica that can be used into breeding programs.

Aims: This study characterized biochemical compound variability that influence green bean quality in C. canephora as a basis for identifying heterogeneous genotypes for use in crop improvement because genetic erosion aided by climate change effects is gradually threatening the cultivation of Original Research Article Aluka et al.; AJEA, 12(2): 1-13, 2016; Article no.AJEA.23004 2 Ugandan Robusta coffee (Coffea canephora) local races. Study Design: Four hundred and fifty four accessions from twenty four districts were analyzed with Near Infra Red Spectroscopy (NIRS) for six biochemical compounds using calibrations developed at CIRAD, France. Place and Duration of Study: This work was conducted at the National Coffee Resources Research Institute (NaCORRI), Uganda between January 2007 and December 2013. Methodology: Spectrometer Nirsystem 6500 Foss(Denmark) machine and Software ISI NIRS 2 version 4.11 (Infra Soft International, Port Matilda, USA) were used to analyze ground samples in diffuse reflectance from 400 nm to 2500 nm (2 nm steps) and predictive models were used to quantify the biochemical contents in the green beans. Data was analyzed with XLSTAT version 2011.2.05 (Addinsoft), Paris, France. Results: Chlorogenic acid and fat concentrations of 13.26 and 13.19% dry matter respectively reported in this study, were much higher than 5.88 and 9.0% dry matter respectively reported earlier. Caffeine concentrations were positively significantly correlated with cholorogenic acid but negatively significantly correlated with trigonelline, sucrose, fat and dry matter contents. Caffeine and chlorogenic acid concentrations increased with age whereas trigonelline declined as trees aged. Chlorogenic acid and trigonelline concentrations were at their lowest levels in elevations of between 10001200 metres above sea level and like fat and dry matter concentrations, the compounds were at their highest levels in higher elevations of about 1500 metres above sea level. Local landraces, ‘’nganda’’ and ‘’erecta’’ had higher concentrations of chlorogenic acid, sucrose and caffeine than improved, hybrid and commercial types. Conclusions: Ugandan C. canephora caffeine content was lower than that of West-African Robusta coffee but higher than that of Arabica coffee. Four distinct diversity groups derived from the six biochemical compounds represented the major organoleptic categories. The results reported here will be useful in defining the desirable cup qualities of Robusta coffee as demanded by world markets.

La mission était centrée sur le Comité de Pilotage du projet REGEPE, qui a eu lieu le 2 octobre 2018. Les jours précédents ont été consacrés à la préparation du Comité de Pilotage, à des rencontres diverses de personnes à impliquer dans le projet (CTG, DAAF, Université de Guyane). En présence des collègues du CRB PT de Guadeloupe, le Comité de pilotage du CRB PPG a eu lieu le 1er octobre, et a permis de faire le point sur le CRB dans son environnement (station de Combi), son périmètre et les perspectives en termes de travaux et de suivi. Les problèmes d'infrastructure et de personnel sont particulièrement importants, et ont des conséquences sur les projets développés, y compris le projet REGEPE. Le Comité de Pilotage du projet REGEPE a regroupé les intervenants du projet (chercheurs Cirad et INRA, CTG, Université de Guyane, DAAF). Une présentation des différentes composantes du projet a été faite, des discussions très intéressantes ont eu lieu sur les éléments du projet. Ce premier Comité de Pilotage a permis de discuter du déroulement du projet et des principaux enjeux liés au CRB, à l'évolution de son périmètre, à la certification et à ses contraintes. Les derniers jours de la mission ont permis de revoir la station de Combi et les collections, et de contacter des agriculteurs de la région Ouest.