Correspondence between genetic structure and farmers' taxonomy - a case study from dry-season sorghum landraces in northern Cameroon

Soler Clélia, Saidou Abdoul-Aziz, Hamadou Tuong-Vi, Pautasso Marco, Wencelius Jean, Joly Hélène. 2013. Correspondence between genetic structure and farmers' taxonomy - a case study from dry-season sorghum landraces in northern Cameroon. Plant Genetic Resources, 11 (1) : 36-49.

https://doi.org/10.1017/S1479262112000342

Article de revue ; Article de revue à facteur d'impact

Version publiée - Anglais
Accès réservé aux personnels Cirad
Utilisation soumise à autorisation de l'auteur ou du Cirad.
document_569022.pdf
Télécharger (724kB)

Quartile : Q3, Sujet : PLANT SCIENCES

Résumé : The study of the genetic structure of cultivated plant populations maintained by farmers is of great importance for evolutionary and conservation biology. Such studies help understand the bases of crop evolution and conservation in relation to farmers' practices. In this study, we assessed the genetic structure underlying landrace diversity of dry-season sorghum. This crop constitutes a historical model of innovation developed by farmers to extend sorghum cultivation to the dry season. Two types of dry-season sorghum are cultivated. We aimed to assess the link between farmers' taxonomy and molecular genetic structure. We collected both types of dry-season sorghum in two villages of northern Cameroon which represented 20 landraces. These landraces were genotyped using eight polymorphic microsatellite markers. This study compared two clustering methods: a Bayesian method (STRUCTURE) which is based on explicit genetic assumptions and the discriminant analysis of principal component method. The latter, more recently proposed, is based on the combination of principal component analysis and discriminant analysis. We noticed a general congruence between these two methods. We also used both methods to infer the genetic structure of our sample. Our results showed strong genetic structuring of the landraces, with K ¼ 14 genetic clusters. We then analysed the fit between farmers' taxonomy and genetic structure. The data suggested that each type and each landrace corresponds to a given genetic entity. This pattern was robust across both villages, despite differences in cultural practices.

Mots-clés Agrovoc : Sorghum, variété indigène, agriculteur, conservation des ressources, génétique des populations, variation génétique, génotype, taxonomie, sécheresse, saison sèche, méthode statistique