LAVIA graciela Ines
Genome re-assignation of Arachis trinitensis (Sect. Arachis, Leguminosae) and considerations on its implication in the genetic origin of peanut
ROBLEDO, G.; LAVIA, G.I.; SEIJO, J.G.
GENETICS AND MOLECULAR BIOLOGY
SOC BRASIL GENETICA
Año: 2010 vol. 33 p. 714 - 718
Abstract The karyotype structure of Arachis trinitensis was studied by conventional Feulgen staining, CMA/DAPI banding and rDNA loci detection by fluorescence in situ hybridization (FISH) in order to establish its genome status and test the hypothesis that this species is a genome donor of cultivated peanut. Conventional staining revealed that the karyotype lacked the small ?A chromosomes? characteristic of the A genome. In agreement with this, chromosomal banding showed that none of the chromosomes had the large centromeric bands expected for A chromosomes. FISH revealed one pair each of 5S and 45S rDNA loci, located in different medium-sized metacentric chromosomes. Collectively, these results suggest that A. trinitensis should be removed from the A genome and be considered as a B or non-A genome species. The pattern of heterochromatic bands and rDNA loci of A. trinitensis differ markedly from any of the complements of A. hypogaea, suggesting that the former species is unlikely to be one of the wild diploid progenitors of the latter.