Patterns of rice diversity from SNP delineated the origin of the atypical O. sativa group in Madagascar from intermediary forms of the Indian sub-continent

Ahmadi Nourollah, Billot Claire, Droc Gaëtan, Brunel Dominique, Frouin Julien, Ramanantsoanirina Alain, McNally Kenneth L., Courtois Brigitte, Glaszmann Jean-Christophe. 2013. Patterns of rice diversity from SNP delineated the origin of the atypical O. sativa group in Madagascar from intermediary forms of the Indian sub-continent. In : 7th International Rice Genetics Symposium (RG7), Manila, Philippines, 5-8 November 2013. International Rice Research Institute. s.l. : s.n., Résumé, 1 p. International Rice Genetics Symposium. 7, Manille, Philippines, 5 November 2013/8 November 2013.

Paper without proceedings
Published version - Anglais
Use under authorization by the author or CIRAD.

Télécharger (69kB) | Preview

Abstract : Madagascar Island was one of the last major Old World areas where human settlement was accompanied by the introduction of Oryza sativa. Early studies had reported the presence of a rice group specific to Madagascar. Using 1536 SNP markers, we compared diversity patterns between a panel of 147 Malagasy rice varieties, a reference panel of 370 Asian varieties and representatives of wild relatives of O. sativa. Migration bottleneck has resulted in 30-40% reduction of diversity among the indica and japonica groups in Madagascar. The Malagasy panel showed many fewer indica x japonica recombinations compared to the Asian panel, suggesting that the two groups had undergone much less recombinations when migration to the Island occurred. The existence of the Malagasy-specific group (Gm) was confirmed. Its diversity patterns positioned it halfway from indica and aus groups. Madagascar also hosted cold tolerant tropical japonica varieties, with very long grain. The Gm group most probably arose from founder effect from intermediary forms of rice originated from either India or Sri Lanka that did not belong to the four majors O. sativa groups. It then underwent human selection for cold tolerance. Signs of inter-group recombinations were also observed, but recombinations did not seem to have played a major role in the dynamics of rice adaptation to the Island's agro-ecological constraints. Connections between Gm and O. rufipogon from its putative area of origin reinforce the hypothesis of multiple and diffuse domestication of O. sativa as opposed to two independent domestications occurring in two distinct geographical areas. (Texte intégral)

Classification Agris : F30 - Plant genetics and breeding
F70 - Plant taxonomy and geography

Auteurs et affiliations

  • Ahmadi Nourollah, CIRAD-BIOS-UMR AGAP (FRA) ORCID: 0000-0003-0072-6285
  • Billot Claire, CIRAD-BIOS-UMR AGAP (FRA)
  • Droc Gaëtan, CIRAD-BIOS-UMR AGAP (FRA)
  • Brunel Dominique, INRA (FRA)
  • Frouin Julien, CIRAD-BIOS-UMR AGAP (FRA)
  • Ramanantsoanirina Alain, CENDRADERU (MDG)
  • McNally Kenneth L., IRRI (PHL)
  • Courtois Brigitte, CIRAD-BIOS-UMR AGAP (FRA) ORCID: 0000-0003-2118-7102
  • Glaszmann Jean-Christophe, CIRAD-BIOS-UMR AGAP (FRA) ORCID: 0000-0001-9918-875X

Source : Cirad - Agritrop (

View Item (staff only) View Item (staff only)

[ Page générée et mise en cache le 2019-09-30 ]