PHYLOGENY OF NORTH-AMERICAN ORYZOID GRASSES AS CONSTRUED FROM MAPS OF PLASTID DNA RESTRICTION SITES

Restriction sites for six enzymes were mapped for the plastid DNAs of eight species of oryzoid grasses from temperate North America together with Olyra latifolia using biotin-labeled probes from Oryza sativa. Cladistic analysis of the data indicated the existence of one, most-parsimonious cladogram of 56 steps. Two species of Leersia differed by only one restriction site mutation, and two species of Zizania differed by only two mutations, whereas Luziola fluitans and L. bahiensis differed by 15 mutations. The restriction sites data strongly support two monophyletic clades corresponding to Oryzinae and Zizaniinae, but only weakly support the traditionally hypothesized alliance of Zizaniinae with other monoecious oryzoid grasses.