DISTRIBUTION AND PHYLOGENY OF POTAMOPHILA-PARVIFLORA RBR A WILD RELATIVE OF RICE FROM EASTERN AUSTRALIA

Potamophila parviflora is a wild relative of rice from Eastern Austral ia. The species was found in the Richmond, Clarence, Macleay and Hasti ngs River systems of northern New South Wales. Existing populations ha d wider leaves (10-15 mM) than those previously reported (4-6 mM). Thi s species and North American wild rice, Zizania palustris were investi gated as genetic resource for rice improvement. Both species, Potamoph ila, and Zizania, occur in colder climates than rice (Oryza sativa). S equencing of the ITS1 of the ribosomal genes of these two species indi cated that Zizania and Potamophila were more closely related to each o ther than either was to Oryza sativa. Potamophila has a similar number of chromosomes (n=12) and a greater sequence homology to rice and may thus be a better source of useful genes for rice improvement.