The First Appearance of Polyploid Nuclei in Primary Roots of Two Diploid Angiosperms

In Anchusa capensis, where the polyploid divisions are restrictedto a particular time and place in germination, cytophotometricanalysis showed that the polyploid cells arise at the time ofconversion of the globular-shaped embryo to the heart-shapedembryo. In Spinacia oleracea, where the divisions occur throughoutthe growth of the root, these polyploid cells do not arise duringembryogenesis but during germination and subsequent growth. Anchusa capensis Thunb., summer forget-me-not, Spinacia oleracea L., spinach, root meristem, polyploid divisions, determinate divisions, indeterminate divisions, germination, embryogenesis, cytophotometry