Fig. 8. Phenotypic analysis of 10-day old wild-type and antisense roots. (A,B) Wild-type (A) and antisense (B) roots stained with Aniline Blue. The cell elongation zone of wild-type roots has small, undifferentiated cells with no root hairs. In contrast, antisense roots exhibit disorganized, enlarged, and precociously differentiated cells with root hairs just above the RAM. (C,D) Median optical sections of wild-type (C) and antisense (D) roots stained with propidium iodide showing the cell elongation zone. Note the densely cytoplasmic, small cells with large centrally located nuclei in the wild type (C) compared with the enlarged, vacuolated (v) cells with asymmetrically located nuclei in the epidermal and cortical cell layers in the antisense roots (D). In the antisense root, cell differentiation is also evident from the presence of fully differentiated xylem vessels (D, arrow). (E-F) Median optical sections of wild-type (E) and antisense (F) roots stained with Aniline Blue. Cell organization in wild-type roots is radially symmetric and the quiescent center (arrow in E) is well defined. In antisense roots (F) enlarged epidermal (e) and cortical (c) cells occur in the cell elongation zone, and the quiescent center is disorganized (H). Bars: 250 µm (A,B); 10 µm (C); and 50 µm (D-F).