Abstract

ARNAO, Erika et al. Evaluation of genetic diversity in rice subespecies using aflp and microsatellite markers. Agronomía Trop. [online]. 2007, vol.57, n.1, pp.45-50. ISSN 0002-192X.

Molecular markers represent a powerful tool for genetic diversity assessment and identity determination especially in genetic narrow based rice varieties. This study aimed to assess the genetic diversity of Indica and Japonica rice subspecies using SSR molecular markers and AFLPs. We evaluated 12 rice Venezuelan varieties (Indica) and 12 Chilean varieties (Japonica) with 13 microsatellite markers (SSR) and four AFLP primer combinations. Presence (1) and absence (0) of bands for each microsatellite (SSR) and AFLP primer combination were scored for each variety, and then converted into similarity and distance genetic matrix for SSR and AFLP, respectively, to construct a cluster by the UPGMA method. Also a Principal Component Analysis was performed. A total of 70 alleles were obtained from the 13 SSRs, with an average of 5,64 alleles per locus, and a polymorphic information content of 0,60. A total of 82 bands were generated from four AFLPs combinations, from which 43 (51,8%) resulted polymorphic. Both grouping methods classified the varieties in two groups: first one corresponded to the Japonica subspecies varieties (Chilean) and the second to the indica subspecies varieties (Venezuelan). Japonica group showed a higher genetic diversity than the Indica group, and in general all varieties could be differentiated. Our results suggest that a small number of markers can generate enough amount of information useful to estimate genetic diversity between rice subspecies and to identify varieties.

Keywords : AFLPs; microsatellites; Oryza sativa L; genetic diversity.