Figure 2.

Distribution of nutrients in leaf tissues of sunflower examined using XFM following foliar fertilization with Zn. A and B, Distribution of Zn (A) and Ca (B) in an intact, hydrated leaf of sunflower to which two 5-μL droplets of ZnSO₄ (1,000 mg L⁻¹ Zn) had been applied on the adaxial surface toward the tip. Note that the highest concentrations of foliar-absorbed Zn accumulated in the trichomes (A), as also can be seen from the high Ca concentrations in these regions (B). C, The concentrations shown for the transect correspond to the dotted white line in A. D, Cross section of a sunflower leaf to which a droplet of ZnSO₄ had been applied on the adaxial surface. The entire adaxial area shown was from beneath the droplet.