SOMATIC-CELL CRYOPRESERVATION AND PROTOPLAST REGENERATION OF IMPORTANT DISEASE-RESISTANT WILD-RICE ORYZA-MEYERIANA BAILL

Oryza meyeriana Baill is one of the three wild rice species found in C hina. O. meyeriana possesses valuable characteristics but is reluctant in cell culture in vitro. In a series of experiments, callus with no regeneration ability was induced from young panicle of O. meyeriana. T he callus was subcultured and propagated. Embryogenic cell clones were obtained after cryopreservation. Suspension cultures were established and protoplasts were isolated and regenerated into plants. Results of artificial inoculation of Xanthomonas campestris pv. Oryzae showed th at the strong resistance did not change in the regenerated plants. The development of protoplast-to-plant system is an important progress to wards utilization of O. meyeriana via cellular engineering. The experi ments demonstrated that cryopreservation of plant calli was a new way to obtain embryogenic cell line.