BAIRD, WM. VANCE1*, GINGER SWIRE-CLARK1, SUSANA S. NEVES2, ASHLEY L. ST. JOHN1, PRIYESH PATEL3, LAUREN YARROW1, and KHIDIR W. HILU2. 1Horticulture Department, Clemson University, Clemson, SC 29634-0375; 2Department of Biology, Virginia Tech, Blacksburg, VA 24061; 3Governor's School for Science and Mathmatics, Hartsville, SC. - Evolution in Eleusine with emphasis on polyploid species using ITS and trnT-F sequence information.
Eleusine (Poaceae, Chloridoideae) is comprised of nine annual
and perennial species of African origin, except for the New World
species E. tristachya. The genus includes the allotetraploid
cereal crop E. coracana ssp. coracana (finger millet).
Previous studies concluded that the phylogenetic relationship among
Eleusine species is not well resolved, particularly among the
perennials. To address these questions and examine the potential for
multiple origins of the polyploids, DNA sequence variation from the
nuclear ITS and the plastid trnT-F regions were analyzed and
compared. The morphologically distinct E. multiflora and the
perennial E. floccifolia share a plesiomorphic large indel with
the outgroup species. The annuals E. coracana and E.
indica formed a strongly supported lineage. The position of the
third annual E. tristachya was inconsistent in the ITS and
trnT-F phylogenies. Although the phylogenetic relationships
among the annuals is complex in the ITS analysis due to the presence
of two loci, the demonstrated relationship sheds light on the
evolution of the polyploid species E. coracana ssp.
coracana and ssp. africana (wild finger millet).
Key words: Eleusine, finger millet, molecular systematics, polyploidy