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Gestions locales et dynamiques régionales de la diversité variétale du manioc en Amazonie

Local management and regional dynamics of varietal diversity of cassava in Amazonia

Genetics Selection Evolution volume 33, Article number: S465 (2001) Cite this article

Résumé

- Le manioc constitue la base de l’alimentation de la très grande majorité des populations amazoniennes et leur principale culture. Selon les régions et les populations (amérindiennes, métissées ou d’immigration récente) cette culture s’accompagne d’une plus ou moins ample diversité variétale, de deux à trois variétés cultivées par parcelle à une trentaine. Les stratégies de conservation des ressources phytogénétiques doivent s’appuyer tant sur une meilleure compréhension des bases génétiques de cette diversité que sur les conditions de production ou de maintien de celle-ci. La recherche comparative menée associe des approches génétique, écologique, ethnobiologique et socio-anthropologique et s’attache à expliciter les liens entre diversité variétale, pratiques agricoles et représentations associées, et environnement socio-économique. Les analyses génétiques soulignent un important polymorphisme inter et intravariétal. Les résultats montrent aussi la spécificité de chaque groupe culturel quant à la valeur accordée aux variétés, aux modalités de circulation des boutures et à la place donnée aux maniocs issus de graines. Des dynamiques plus globales jouent aussi sur la diversité variétale (commercialisation croissante de farine, changements d’habitudes alimentaires, politiques agricoles). Elles tendent à réduire le nombre de variétés cultivées et à modifier la structure de cette diversité. Les résultats plaident en faveur de la constitution de pôles régionaux de conservation, qui pourraient prendre le relais des structures centralisées actuelles ou les compléter.

Abstract

Cassava is the staple food crop of the great majority of Amazonian populations. Depending on the region and on the type of population (Amerindians, mixed, or recent immigrants), a more or less high diversity of manioc varieties are grown, ranging from two to three varieties per farm to 30 or more. Strategies for conserving genetic resources of manioc must be based on firm understanding of the genetic base of this diversity and on how this diversity is produced and maintained. The comparative research we have conducted incorporates genetic, ecological, ethnobiological and social-anthropological approaches, and aims to elucidate the causal links between varietal diversity, agricultural practices and associated representations, and socio-economic environment. Genetic analyses have demonstrated a high degree of polymorphism, both within and among varieties. Results of ethnobiological studies have also shown that cultural groups vary in the value attached to varietal diversity, as revealed both in the patterns of circulation of propagation material (stem cuttings) and the place given to manioc originating from spontaneous seedlings. In addition to these factors affecting local dynamics, more global dynamics - increasing commercialisation of flour, changing food habits, and changing agricultural policies - also affect varietal diversity. These factors tend to reduce the number of varieties cultivated and to modify the structure of diversity. Our results suggest the utility of developing regional poles of conservation, which can extend or complement the centralised structures now in place.

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Authors and Affiliations

  1. Centre d’écologie fonctionnelle et évolutive, Cnrs, Montpellier, France

    Doyle McKey & Marianne Élias

  2. Institut de recherche pour le développement / Instituto Socioambiental, Brasilia, Brasil

    Laure Emperalre

  3. Ladyss - Cnrs, Université Paris-10, Nanterre, France

    Florence Pinton

  4. Laboratoire de systématique et évolution des végétaux, Université Paris-sud, France

    Thierry Robert

  5. Laboratoire d’ethnobiologie-biogéographie, Muséum national d’histoire naturelle, Paris, France

    Sylvain Desmoulière

  6. Department of Anthropology, Eliot College, University of Kent, Canterbury, UK

    Laura Rival

Authors
  1. Doyle McKey
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  2. Laure Emperalre
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  3. Marianne Élias
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  4. Florence Pinton
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  5. Thierry Robert
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  6. Sylvain Desmoulière
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  7. Laura Rival
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Correspondence to Doyle McKey.

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McKey, D., Emperalre, L., Élias, M. et al. Gestions locales et dynamiques régionales de la diversité variétale du manioc en Amazonie. Genet Sel Evol 33 (Suppl 1), S465 (2001). https://doi.org/10.1186/BF03500895

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  • DOI: https://doi.org/10.1186/BF03500895

Keywords

  • manihot
  • Amazonie
  • écologie des populations
  • ethnobiologie
  • socio-anthropologie

Mots clés

  • manihot
  • Amazonia
  • population ecology
  • ethnobiology
  • social anthropology

Genetics Selection Evolution

ISSN: 1297-9686