Figure 3.

Pollen Germination on Rosette Leaves of Col-0/gl1 Control Plants and Cutinase-Expressing Arabidopsis Plants.

(A) Mature leaf of a Col-0/gl1 plant fixed 20 hr after pollen application, stained with aniline blue, and visualized by UV excitation at 340 to 380 nm. The absence of green fluorescence demonstrates that no callose was deposited in the pollen and that no pollen tubes rich in callose developed.

(B) Leaf of cutinase-expressing plant (line T-5) fixed 20 hr after pollen application, stained with aniline blue, and visualized by UV excitation at 340 to 380 nm. The green fluorescence indicates callose in pollen and particularly in outgrowing pollen tubes (Pt). In addition, callose was deposited in epidermal cells (E) underneath the germinating pollen as a defense response to pollen tubes penetrating the cuticle.

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