ARS | Publication request: A PHYLOGENY STUDY OF MEDICAGO SPECIES BASED ON RIBOSOMAL DNA ITS SEQUENCES

Submitted to: Acta Botanica Sinica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 10, 2002
Publication Date: January 10, 2003
Citation: Yi, S., Liang, A., Wang, J., Skinner, D.Z. 2003. A phylogeny study of medicago species based on ribosomal dna its sequences. Acta Botanica Sinica 23(2):242-246.

Interpretive Summary: Part of a gene that is similar in numerous plant species was examined at the molecular level to assess the ancestral relationships of 28 Medicago species related to alfalfa. Four of the species were much more closely related to alfalfa than the other 23 species, and classification sections previously described were not well supported by the molecular data. These results suggest that alfalfa is relatively distinct from related species, and the relationships of the other species are somewhat different from previously believed.

Technical Abstract: Nucleotide sequence variation in the internal transcribed spacer (ITS) region of the ribosomal gene was investigated in 28 Medicago species,and Metilotus officinalis was included as an outgroup. Phylogenetic analysis resulted in a tree in general agreement with the current taxonomy of the genus. The study revealed that M. falcata is the closest relative of M. sativa, M. hybrida, M. cancellata and M. prostrate are also close to M. sativa. The results confirmed that the formerly Trigonella species should be included in the genus Medicago. The classification of sections Heynianae,Platycarpae and Spirocarpos may need to be re- considered.