Record Details

Analyse multiéchelle de la diversité génétique des sorghos : compréhension des processus évolutifs pour la conservation in situ

OAR@ICRISAT

View Archive Info
 
 
Field Value
 
Relation http://oar.icrisat.org/686/
http://dx.doi.org/10.1684/agr.2008.0180
 
Title Analyse multiéchelle de la diversité génétique des sorghos : compréhension des processus évolutifs pour la conservation in situ
 
Creator Sagnard, F
Barnaud, A
Dembele, D
Deu, M
Barro, C
Luce, C
Toure, A
Bezançon, G
 
Subject Agriculture-Farming, Production, Technology, Economics
 
Description Using microsatellite genetic markers, we analyzed 1,518 sorghum samples collected at different spatial scales in Burkina Faso, Mali, Niger, and in the village of Wanté, from the landrace to the country scale. Genetic diversity and differentiation parameters were estimated to assess the effects of the main evolutionary processes on sorghum genetic diversity. The genetic variability found within a variety is mainly the result of the sorghum reproduction biology and the genetic drift process caused by the limited number of reproductive individuals at the time of variety introduction into a household or each year when farmers select their seeds. At the village scale, a low correlation is observed between the diversity of vernacular names and the genetic diversity assessed by microsatellites. No spatial genetic structuration is observed among villages more than 30 kilometers apart. This point highlights that traditional seed systems operate at a very local scale. In Mali, a similar proportion of allelic richness is observed along a longitudinal transect and a latitudinal gradient that crosses a larger range of agroclimatic conditions. At the country scale, sorghum exhibits more genetic diversity in Niger than in Mali despite a lower agroclimatic range in Niger. These results demonstrate that the diversity of human groups acts together with the agro-ecological factors to shape the structure of sorghum genetic diversity. An important proportion of the overall genetic diversity present in the Cirad (Centre de coopération internationale en recherche agronomique pour le développement) "core collection" is found in Mali and Niger. The tremendous diversity cultivated by farmers in traditional agroecosystems of Western Africa supports the relevance of in situ approaches for sorghum conservation programs in this region. Both conservation and crop improvement requirements can be achieved through a better use of local germplasm in decentralized breeding programs. (Summary in English).
 
Date 2008
 
Type Article
PeerReviewed
 
Format application/pdf
 
Language en
 
Rights —
 
Identifier http://oar.icrisat.org/686/1/CahiersAgricultures17_2_114-121_2008.pdf
Sagnard, F and Barnaud, A and Dembele, D and Deu, M and Barro, C and Luce, C and Toure, A and Bezançon, G (2008) Analyse multiéchelle de la diversité génétique des sorghos : compréhension des processus évolutifs pour la conservation in situ. Cahiers Agricultures, 17 (2). pp. 114-121.