Whereas fine stripe sectors were absent from the top 2 or 3 leaves, sectors for other factors were usually present in the top 12 or 13 leaves. In most cases, characteristically, the widest sectors were located along the edges of the blade, especially in the upper leaves. A similar pattern is present in sr2 plants also, but in all cases the sectors along the edges in the leaf sheath were wider than those in the leaf blade. The extents of lateral proliferation of a lineage along the edges of sheath and blade show no relationship and these must be regulated by independent factors or genes. Extent of striping at different node levels, counting from the top.
Thick line represents maximum expression for that factor.
Pattern of striping in several mutant types. Whether the exclusive expression of these factors in LI depends on the specific genes or on the background of the material is yet to be established. The two cell layers of the shoot apex maintain more or less their distinctiveness as most of the cell divisions are anticlinal. It is of considerable interest to determine if genetic factors regulate the time and location of periclinal cell divisions. The presence of wide or small sectors could be genetically regulated.