Karyotype and C-banding in Medicago noëana Boiss., Leguminosae

Abstract

Somatic chromosomes of Medicago noëana Boiss (2n=16), a wild annual species belonging to the section Rotatae of the subgenus Spirocarpos, were analyzed to confirm the chromosome number as 2n=16 and to characterize each chromosome pair on the basis of its length and arm ratio value. The karyotype of this species was symmetric and consisted of four median chromosomes and three submedian chromosomes. The C-banded metaphases included a considerable amount of heterochromatin which is localized at the centromeric region of each chromosome. The results allow us to make some considerations on the genus Medicago and to demonstrate that cytogenetic studies can provide useful information for breeding programs.