Regeneration of protoplast-derived green plants of Kentucky blue grass (Poa pratensis L.).

Green plants were repeatedly regenerated from suspension-derived protoplasts of Kentucky blue grass (Poa pratensis L.) cv. "Geronimo". One suspension was capable of donating competent protoplasts during long-term culture i. e. 10-16 months after its establishment. The plating efficiency of the protoplasts from three different suspension lines varied from 0.004% in the lowest up to 1.5% in the highest responding line, using agarose-bedding in nutrition medium devoid of nurse or feeder cultures. Green plants germinated from polyembryos, which developed from 0.4-2.7% of the protoplast-derived microcolonies. A total of 127 plants were successfully transferred to soil.