Phylogeny, Development, and Taxonomy of Setaria and its Relatives

University Of Missouri-Saint Louis, Saint Louis MO

Investigators

Abstract

The cereal crops foxtail millet and pearl millet, and noxious weeds such as green foxtail and sandbur are all closely related members of the grass family, and are part of a group of 310 species descended from a single ancestor. These plants are all characterized by odd "bristles" interspersed among their flowers; the bristles are highly modified branches. This project will determine the precise relationships among as many species as possible in the "bristle group" using DNA sequences from the nucleus and the chloroplast. At the same time, the development of the seed head (inflorescence) and flowers will be studied for a precise description of how the species differ. Along with this, the graduate student supported on the grant will determine how many species are in the foxtail millet group, what the species look like, and will write identification guides to them. Because there is already information on the species in North and South America, this part of the project will focus on Asia and Africa. The information gained in this project will connect directly with other information already available on foxtail millet and the panicoid grasses. The genes that control morphological variation in foxtail millet are under active investigation, and some of these are similar to known genes in maize. It should soon be possible to describe morphological variation in the clade in terms of the genes involved. This will help answer questions about how species and larger groups are formed. The resulting study will provide a direct and explicit link between phylogeny, developmental morphology, and taxonomy, and will provide a framework for work on the evolution of development