A procedure for chromosome doubling of the white cocoyam (Xanthosoma sagittifolium) type was
established by using colchicine and oryzalin treatments to in vitro plantlets. Flow cytometry was
successfully used for analyzing ploidy levels within three cocoyam types and regenerated plants.
Treating in vitro white cocoyam with 0.05% colchicine for 7 days produced tetraploids. The oryzalin
treatment (0.05% for 3 days) produced only mixoploids, but it has in turn, a lower rate of mortality.
Therefore, in white cocoyam, oryzalin could constitute an alternative to the use of colchicine, whenever
the selection and stabilization of polyploids induced by this reagent will be achieved.