Patterning: the selection of leaf initiation site
As stated above, initiation of a leaf requires that a field of cells
exists from which a leaf can be formed. In that respect, the
mechanism by which the SAM is maintained is essential to
leaf formation. However, there is little evidence that the
process of cell proliferation in the SAM in any way determines
the fate of those cells, although there has been some discussion
on this point (Fleming, 2002; Klar, 2002). The SAM can thus
be viewed as a cell-generating machine which produces a field
of tissue in which the mechanism(s) of morphogenesis and