Microdensitometry at different density thresholds of Feulgen-stained nuclei shows that both 2C and 4C dormant cells of the unsprouted root of Allium cepa L. bulbs have a smaller nuclear volume and a larger amount of dense chromatin than their counterpart G1 and G2 cells of the proliferating root. The analysis seems to differentiate between cells in the proliferate compartment from those in the non-proliferative compartment (Go and Go,2 cells).