Abstract: By counting the chromosome number of root tip cells in 18 regenerated plants derived from protoplasts of Actinidia eriantha Benth., the authors found 12 euploid plants and 6 mixoploid plants. Of the 12 euploid plants, 6 were diploid (2n = 2x = 58) and the other 6 were tetraploid (2n =4x = 116). The chromosome numbers of the mixoploid plants varied from 59 to 203. Mttltinueleate phenomenon was also observed in the interphase cells of 10 protoplast-derived plants. Cells with binuclei or trinuelei were common and cells having heptanuclei were also seen occassionally. Muhinucleate phenomenon did not occur in the control, i. e., the donor plant, where the chromosome number was 2n = 2x = 58.

Key words: Actinidia eriantha, Protoplast-derived plants, Chromosome number, Muhinueleate Phenomenon