Histoire d’une innovation agricole récente à l’échelle régionale : sélection et circulation des sorghos repiqués dans le bassin tchadien

International audienceLe sorgho repiqué a fait l’objet d’une large diffusion dans le bassin du lac Tchad au XXe siècle. Cette culture présente une forte diversité variétale. Les nomenclatures paysannes suggèrent des groupes géographiquement distincts, subdivisés en variétés locales selon des critères qui peuvent varier en fonction des sociétés. À partir d’une taxonomie simplifiée en langue véhiculaire (fulfulde) et de la structure des diversités agro-morphologique et génétique du sorgho repiqué, nous montrons que la variation repose moins sur la définition de catégories taxonomiques intermédiaires (groupes variétaux) que sur celle, plus fine, de taxons terminaux en langues locales (types nommés). Cela est expliqué à l’échelle locale par les pratiques de sélection et de gestion variétale des agriculteurs. La proximité génétique des sorghos repiqués avec certaines populations de sorgho pluvial apporte de nouveaux éléments soutenant les hypothèses sur l’histoire évolutive des sorghos repiqués. L’association du sorgho repiqué à plusieurs clusters génétiques et plusieurs haplotypes chloroplastiques, la circulation régionale relativement récente ainsi que le statut de vivrier marchand du sorgho repiqué ne permettent pas de tracer des frontières géographiques ou culturelles dans la répartition actuelle du sorgho repiqué

Farmer seed networks make a limited contribution to agriculture? Four common misconceptions

a b s t r a c t The importance of seed provisioning in food security and nutrition, agricultural development and rural livelihoods, and agrobiodiversity and germplasm conservation is well accepted by policy makers, practitioners and researchers. The role of farmer seed networks is less well understood and yet is central to debates on current issues ranging from seed sovereignty and rights for farmers to GMOs and the conservation of crop germplasm. In this paper we identify four common misconceptions regarding the nature and importance of farmer seed networks today. (1) Farmer seed networks are inefficient for seed dissemination. (2) Farmer seed networks are closed, conservative systems. (3) Farmer seed networks provide ready, egalitarian access to seed. (4) Farmer seed networks are destined to weaken and disappear. We challenge these misconceptions by drawing upon recent research findings and the authors' collective field experience in studying farmer seed systems in Africa, Europe, Latin America and Oceania. Priorities for future research are suggested that would advance our understanding of seed networks and better inform agricultural and food policy

Farmer seed networks make a limited contribution to agriculture? Four common misconceptions

The importance of seed provisioning in food security and nutrition, agricultural development and rural livelihoods, and agrobiodiversity and germplasm conservation is well accepted by policy makers, practitioners and researchers. The role of farmer seed networks is less well understood and yet is central to debates on current issues ranging from seed sovereignty and rights for farmers to GMOs and the conservation of crop germplasm. In this paper we identify four common misconceptions regarding the nature and importance of farmer seed networks today. (1) Farmer seed networks are inefficient for seed dissemination. (2) Farmer seed networks are closed, conservative systems. (3) Farmer seed networks provide ready, egalitarian access to seed. (4) Farmer seed networks are destined to weaken and disappear. We challenge these misconceptions by drawing upon recent research findings and the authors’ collective field experience in studying farmer seed systems in Africa, Europe, Latin America and Oceania. Priorities for future research are suggested that would advance our understanding of seed networks and better inform agricultural and food policy

Dans les sillons de l'alliance. Ethnographie de la circulation des semences de sorgho dans l'Extrême-Nord du Cameroun

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Interhousehold variability and its effects on seed circulation networks: a case study from northern Cameroon

We present a detailed ethnographic case study of sorghum seed acquisitions in a smallholder farming society in northern Cameroon. The effects of variability in household demographics and socioeconomic status on observed patterns of seed provisioning are explored alongside other variables such as age and gender. Our data set comprised 223 seed acquisition events. Independence tests (Pearson's chi-square and Fisher's exact tests) were carried out to test for significant dependencies between individual- or household-level characteristics and properties of seed acquisition events (categories of seed source, social relationship of exchange, and type of landrace). Results indicate that wealth is a structuring factor of the local seed circulation network in as much as it is highly correlated with household composition and size. Members from wealthy households benefit from a more diverse set of seed sources. Their greater number of coresidents and the importance of intrahousehold dynamics of seed transactions also play a role in making wealthy farmers more seed secure than others. The methodological implications of our findings indicate that when documenting seed exchange networks, the collection of data through a single informant or the undertaking of social network analyses at the household level may induce important biases

Gifts or commodities ? The changing statues of seeds in the Northern Cameroon

International audienc

Moorea Lagoon Fishers’ Mental Maps: An Exploratory Analysis of Polynesian Spatial Knowledge

International audienceAbstract This empirical study builds upon prior research concerning cultural influences on spatial mental representations in Oceania. A comprehensive examination of 93 mental maps sourced from 59 lagoon fishers of Moorea (French Polynesia) reveals interesting facts about the way they organize and share their spatial knowledge. Firstly, consistent with previous studies across Oceania, Polynesian fishers exhibit a preference for the allocentric perspective when representing their environment. Secondly, they generally rely on marine landmarks for navigation, with a particular emphasis on four entities: the reef barrier, maritime beacons, coral outcrops, and a key chromatic marker — Moana (blue in Tahitian) — indicating the depth of the lagoon. Finally, the factor analysis we conducted highlights two significant facts: (1) a geographical self‐censorship, demonstrated by the low presence or even the absence of landmarks useful for locating their fishing spots; (2) a continuum between the surface and the depths of the lagoon, showing that surface fishers (line, net, troll, etc.) have a proven knowledge of seabed topography, whereas underwater speargun fishers also rely on landmarks located above the water

Moorea Lagoon Fishers’ Mental Maps: An Exploratory Analysis of Polynesian Spatial Knowledge

International audienceAbstract This empirical study builds upon prior research concerning cultural influences on spatial mental representations in Oceania. A comprehensive examination of 93 mental maps sourced from 59 lagoon fishers of Moorea (French Polynesia) reveals interesting facts about the way they organize and share their spatial knowledge. Firstly, consistent with previous studies across Oceania, Polynesian fishers exhibit a preference for the allocentric perspective when representing their environment. Secondly, they generally rely on marine landmarks for navigation, with a particular emphasis on four entities: the reef barrier, maritime beacons, coral outcrops, and a key chromatic marker — Moana (blue in Tahitian) — indicating the depth of the lagoon. Finally, the factor analysis we conducted highlights two significant facts: (1) a geographical self‐censorship, demonstrated by the low presence or even the absence of landmarks useful for locating their fishing spots; (2) a continuum between the surface and the depths of the lagoon, showing that surface fishers (line, net, troll, etc.) have a proven knowledge of seabed topography, whereas underwater speargun fishers also rely on landmarks located above the water