Effets de Dix (10) Variétés de Sésame (Sesamum indicum (L.)) en Association avec Le Niébé (Vigna unguiculata (L.) Walp) dans la Lutte Contre Striga Gesnerioïdes (Willd.) Vatke. au Niger

Striga gesnerioïdes est une plante parasite qui cause des dégâts importants sur le niébé et les méthodes de lutte testées restent insatisfaisantes. L’étude vise à mettre au point, une référence de technique d’association sésame-niébé pour contribuer à lutter efficacement contre Striga gesnerioïdes. À cet effet, un dispositif en Split-Plot est utilisé sur un terrain naturellement infesté par Striga gesnerioïdes. Trois comptages à des périodes différentes (42, 56 et 70 jours après semis) du nombre de plants de Striga gesnerioïdes émergés par poquet de niébé ont été réalisés. Ainsi, en association dans le même poquet (sésame + niébé), les variétés de sésame EF 146, HC 110, ICN 130, HB 168, Vgr 156 et EF 147 sont efficaces pour atténuer l’émergence de striga. En alternance de poquets (niébé et sésame), les variétés de sésame EF 146, HC 110, ICN 137, EF 147 et 38-1-7 sont efficaces contre striga. Et les variétés de sésame EF 146, Vgr 156, HC 108 et 38-1-7 ont montré leurs efficacités en alternance de lignes avec le niébé. EF 146 est la seule variété de sésame efficace dans toutes les trois mesures de protections. Ces résultats pourraient être vulgarisés au niveau des producteurs de niébé pour booster sa production au niveau national, voir mondial. Striga gesnerioïdes is a parasitic plant that causes significant damage to cowpea and the control methods tested remain unsatisfactory. The study aims to develop a technical reference of sesame-cowpea association to contribute to the effective control of Striga gesnerioïdes. For this purpose, a Split-Plot device is used on land naturally infested by Striga gesnerioïdes. Three counts at different periods (42, 56 and 70 days) of the number of emerged Striga gesnerioïdes plants per cowpea were made. Thus, in combination in the same plot (sesame + cowpea), the sesame varieties EF 146,HC 110, ICN 130, HB 168, Vgr 156 and EF 147 are effective in mitigating Striga emergence. In alternating rows (cowpea and sesame), the sesame varieties EF 146, HC 110, ICN 137, EF 147 and 38-1-7 were effective against striga. And the sesame varieties EF 146, Vgr 156, HC 108 and 38-1-7 showed their efficacy in alternating rows with cowpea. EF 146 is the only sesame variety that is effective in all three protective measures. These results could be disseminated to cowpea producers to boost its production at the national and even global level

Neglected and underutilised species (NUS): an analysis of strengths, weaknesses, opportunities and threats (SWOT)

Despite the growing attention to the neglected and underutilised species (NUS) as a valid instrument to promote not only sustainable agriculture and food systems but also sustainable development in rural areas, attempts to move from good intentions to effective actions have been limited. This is due, among others, to a gap in knowledge about the myriads of existing NUS and their potential. In this context, the present paper provides a comprehensive analysis of the strengths, weaknesses, opportunities and threats (SWOT) of crop NUS. Data for the SWOT analysis were retrieved through a review of the literature carried out in June 2022 on the Web of Science. Strengths relate, inter alia, to adaptability to harsh, marginal conditions, tolerance to biotic and abiotic stresses (e.g. pests and diseases, drought) and low external input requirements of NUS as well as their high medicinal and nutritional values combined with widespread culinary traditions. Weaknesses regard low productivity as well as difficult access to quality seeds, inputs, technologies and knowledge. Higher demand from consumers as well as increasing attention to sustainability and resilience in the whole agri-food system and agroecology represent opportunities for the promotion of NUS to address challenges such as food and nutrition insecurity and poverty. Climate change, biodiversity loss and genetic erosion, land and agroecosystem degradation, loss of traditional knowledge and heritage, and competition from commercial crops are among the main threats to NUS. The SWOT of NUS outlined in this work should inform evidence-based policies and strategies for the promotion of NUS, especially in developing countries. They should also guide the undertakings and actions of all stakeholders interested in the development of NUS value chains

Manger les produits locaux pour manger mieux

Within the EU-funded SUSTLIVES project, this easy to read brochure provides information on the project, project sites, the target neglected and underutilized species being studied in Niger and Burkina Faso as well as information on their importance for nutrition, climate resilience and livelihoods

Frontières des hommes et échanges des plantes cultivées

Une analyse comparative de la relation entre diversités ethnolinguistique et génétique a été menée dans le bassin du lac Tchad sur les variétés de trois espèces : le mil, le sorgho et le pois de terre. Pour le mil, très allogame, les résultats conduisent à proposer l’hypothèse d’une coïncidence entre la distribution des groupes génétiques et celles de groupes ethnolinguistiques. Ainsi, des « barrières » sociales à la diffusion des échanges de variétés révélées par les enquêtes anthropologiques, limitent les flux de gènes. La répartition de la diversité génétique du pois de terre, autogame et de culture souvent marginale, révèle une histoire riche en échanges et circulations des semences, en accord avec un système de dénomination largement partagé par toutes les communautés, et une circulation marchande importante. Le sorgho, préférentiellement autogame, pour lequel les emprunts de variétés sont fréquents, révèle une situation intermédiaire. Les groupes génétiques ont une répartition fragmentée, la sélection pour la conservation de types nommés et le système de reproduction majoritairement autogame limitant les échanges génétiques entre ces groupes.A comparative analysis of the relationships between ethno-linguistic and genetic diversities has been carried out in the Lake Chad basin, on pearl millet, sorghum and Bambara groundnut varieties. Results suggest the hypothesis of a coincidence in spatial distribution of farmers social groups and pearl millet genetic groups, despite its outcrossing mating system. The ethnographic surveys indicate ethnic barriers that reduce exchanges of varieties and gene flow. The Bambara groundnut, a self-pollinated species, is mainly a marginal crop. Its genetic diversity witnesses important seed exchanges that probably occurred throughout the history of the cultivation of this plant in this region. This result is in agreement with both the similar naming systems in the different ethnic groups and the important merchant exchanges of this crop. For sorghum, use and adoption of exotic varieties are frequent, which could contribute to explain the patchy spatial distribution of genetic groups. However, farmer’s selection for the conservation of well-identified varieties and a mainly selfing mating system, contribute to limit gene flow between varieties

Agro-biodiversity in national pathways for food system transformation: case of West Africa

The challenges relating to biodiversity loss, food insecurity and climate change show the urgent need to make transition towards sustainable food systems in West Africa. To bring about such a transition worldwide, the United Nations’ Food Systems Summit was held in September 2021. One of the main outcomes of the Summit was the national pathways to sustainable food systems. This review analyses whether and how agro-biodiversity is addressed in the food system transformation pathways submitted by West African countries in the framework of the Summit. The content analysis suggests that agro-biodiversity is not a central topic in the national transformation pathways. In fact, it is completely overlooked in some pathways documents, and rather marginal in others. Some national documents (cf. Burkina Faso, Ghana, Niger, Nigeria) refer to the promotion of the diversity of crops and farm animals as a means of adapting to climate change, improving livelihoods and diversifying diets thus contributing to nutrition security. Moreover, only a few measures and actions dealing with the valorisation of the neglected and underutilised species (NUS) and traditional crop varieties are included in the national transformation pathways (cf. Guinea, Liberia, Niger, Sierra Leone). The conservation, management and restoration of agro-biodiversity and agro-ecosystems are crucial to boost the transition towards nature-positive food systems in the region. Therefore, a paradigm change is needed in policy, research and practice to conserve the natural resource base and contribute to sustainable development by addressing, inter alia, food insecurity and malnutrition, rural poverty and climate change challenges

Sustainability of neglected and underutilised species (NUS): Towards an assessment matrix for crop species.

Neglected and underutilised species (NUS) are widely claimed to contribute to sustainability and sustainable development. Verifying such a claim implies the use of a scientifically sound assessment tool. In this context, the present article aims to suggest a matrix for the assessment of the environmental, economic and social sustainability of NUS. In particular, the paper provides a set of indicators and metrics to assess the different sustainability dimensions. It draws upon a search carried out on the Web of Science in May 2022 that returned 126 records. Eligible documents underwent two steps: in the first step, indicators, metrics and criteria regarding sustainability were identified; in the second step, expert knowledge was used to systematise the identified indicators and metrics according to the three sustainability dimensions and group them into themes. Agronomic aspects were included in the environmental dimension while nutrition, health and cultural aspects were included in the social dimension. One of the main results of the analysis is that there is a dearth of quality scholarly documents dealing with the assessment of NUS sustainability. Furthermore, economic and social indicators and metrics are hard to find. The operationalisation of the proposed indicators requires their contextualisation taking into consideration the conditions in each country/territory as well as the NUS concerned. A further important step to operationalise the proposed matrix implies the identification of a sustainability threshold and an assessment scale for each indicator. Apart from sustainability assessment, the proposed assessment matrix can allow selecting the NUS that have the highest potential and whose promotion can contribute to the sustainable development of the concerned countries and territories

Orphan crops and sustainability transitions in agri-food systems: Towards a multidimensional and multilevel transition framework

Neglected and underutilized species (NUS i.e. orphan crops) are widely claimed to contribute to sustainable development. However, the relationship between NUS and sustainable agri-food systems is still unclear. Therefore, this paper analyses the role of NUS in the transition towards sustainable and resilient agri-food systems and identifies actions needed and levers of change. It draws upon a systematic review of 35 articles identified through a search performed in July 2022 on the Web of Science. The analysis of the literature was conducted following the Multi-Level Perspective on socio-technical transitions (MLP) and its three elements viz. niches, sociotechnical regime and sociotechnical landscape. The review suggests that the transition dynamics and success depend not only on the features of the niche NUS (cf. strengths and weaknesses), regime (cf. barriers to change and competitiveness of major crops with NUS) and landscape (cf. macro-trends and policies) but also on the interactions among them. The levers of change lie in the areas of policy, market and finance, technology, culture, and science and innovation. Further research is needed to elucidate the mechanisms leading to the mainstreaming of NUS into agri-food systems as well as the dynamics of interaction between niche NUS and commercial, staple crops

Differentiating stages of functional vision loss from glaucoma using the Disc Damage Likelihood Scale and cup:disc ratio

BACKGROUND: Glaucoma staging is critical for treatment planning but has rarely been tested in severe/end-stage disease. We compared the performance of the Disc Damage Likelihood Scale (DDLS) and cup:disc ratio (CDR) using a functional glaucoma staging system (GSS) as the reference standard. METHODS: Post hoc analysis of a randomised controlled trial at the Eye Department of Kilimanjaro Christian Medical Centre, Tanzania. Eligible participants (aged ≥18 years) with open-angle glaucoma, intraocular pressure (IOP) of >21 mm Hg, were randomised to timolol 0.5% eye drops or selective laser trabeculoplasty. Fundoscopy established vertical and horizontal CDRs and DDLS. Visual acuity and static visual fields were graded (GSS). The study used area under the receiver operating characteristic (AROC) curves and Spearman's rank correlation coefficients to compare staging systems. Logistic regression with generalised estimating equations determined risk factors of functional severe/end-stage glaucoma. RESULTS: 382 eyes (201 participants) were evaluated; 195 (51%) had severe or end-stage glaucoma; mean IOP was 26.7 (SD 6.9) mm Hg. DDLS yielded an AROC of 0.90 (95% CI 0.87 to 0.93), vertical cup:disc ratio (vCDR) of 0.88 (95% CI 0.85 to 0.91, p=0.048) for identifying severe/end-stage disease. Correlation coefficients comparing GSS to DDLS and vCDRs were 0.73 and 0.71, respectively. Advanced structural stages, vision impairment, higher IOP and less financial resources were risk factors of functional severe/end-stage glaucoma. CONCLUSION: This study indicates that both structural staging systems can differentiate severe/end-stage glaucoma from less severe disease, with a moderate advantage of DDLS over CDR. Clinical examination of the optic disc plays an important role in addition to functional assessment when managing severe/end-stage glaucoma

Gene flow and pearl millet (Pennisetum glaucum) genetic resource evolution in the Lake Chad Basin : Role of socio-cultural diversity

La résilience des agricultures subsahariennes face aux perturbations environnementales et socio-économiques repose en partie sur le maintien des diversités spécifique, variétale et génétique présentes au sein des agrosystèmes, mais aussi sur la préservation du droit pour les cultivateurs de reproduire et d'échanger librement les semences et les savoirs relatifs aux variétés. Pourtant, peu de données sont réellement disponibles sur la circulation effective des semences et les mécanismes modulant les flux de gènes et les introgressions génétiques entre variétés cultivées dans les agrosystèmes sahéliens. Chez le mil en particulier, il n’existe que des données très parcellaires sur les relations entre la diversité de la plante d’une part et la diversité socio-culturelle des agriculteurs d'autre part. Dans la première partie je me suis intéressé aux interactions entre l’organisation en groupes socio-culturels des agriculteurs et la structure génétique des populations de mil dans le bassin du lac Tchad. Les analyses de la diversité génétique suggèrent l’existence d’une barrière sociale à la diffusion des gènes sur l’ensemble de cette région. Néanmoins ces barrières ne sont pas suffisantes pour empêcher les introgressions génétiques entre populations cultivées par des agriculteurs appartenant à des groupes ethnolinguistiques différents. Dans le deuxième chapitre, je me suis intéressé au rôle des processus d’adaptation locale sur la circulation des gènes. Les résultats m’ont conduit à proposer l’hypothèse selon laquelle les flux de gènes entre types nommés précoces et tardifs sont plus importants dans les régions du nord où la pluviométrie est faible. Enfin dans le troisième chapitre j’ai quantifié la diversité biochimique des grains de mil de plusieurs variétés de mil, dont les usages culinaires varient selon les groupes ethnolinguistiques ou dont les qualités gustatives sont appréciées différemment. J’ai utilisé pour cela une approche combinée de protéomique et de métabolique. Parmi les 1072 spots protéiques quantifiés seulement 7 permettent de distinguer les types nommés photopériodiques des types nommés non ou peu photopériodiques. Les données de métabolomique suggèrent la présence de champignons, qui pourraient être des endophytes, dans certains des échantillons analysés.The resilience of sub-Saharan farming systems to environmental and socioeconomic disturbances is partly based on the maintenance of agro-biodiversity, but also on preserving the right for farmers to reproduce and freely exchange seeds and related knowledge. However, few data are actually available on effective seed flow and on mechanisms modulating gene flow and genetic introgression between landraces grown in Sahelian farming systems. For pearl millet especially, there are only very few data on the relationship between diversity of this crop on the one hand and the socio-cultural diversity of farmers on the other hand. In the first part of my thesis, I was interested in assessing a potential relationship between ethnolinguistic diversity and population genetic structure of pearl millet in the Lake Chad Basin. Analysis of molecular polymorphisms suggests the existence of social barrier to seed flow among ethnolinguistic groups. However, these barriers are not sufficient to prevent genetic introgression between pearl millet populations cultivated by farmers belonging to different ethno-linguistic groups. In the second chapter, I focused on the role of local adaptation on gene flow. The results led me to propose the hypothesis that gene flow between early and late landraces are higher in the northern regions where rainfall is weak. Finally in the third part, I have quantified the biochemical compound of pearl millet seeds belonging to different varieties that show different uses or culinary preferences among farmers belonging to different ethnolingiuistic groups. I used a combined approach of proteomics and metabolics. Among the 1072 protein spots quantified only 7 distinguish the very photoperiodic non photoperiodic landrace. Metabolomics data suggest the presence of fungi, possibly endophytes, in some of the samples analyzed