FIG. 1.

Expanded view of a ryegrass tiller showing tissues used for hyphal counts (shaded areas) and for GUS assays (unshaded areas). In the uppermost sections, the tissue removed for counting was 0.5 cm below the tip of the leaf. Shown is a three-leaf tiller, i.e., a tiller with three mature, nonextending leaves in which the ligular zone (marked by a thick black line) is visible, separating blade and sheath. Some of the tillers only had two mature leaves, lacking the third leaf, and others had only one mature leaf, lacking the second and third leaves. The dashed lines indicate the borders of sections for which results are reported in Table 1 and Fig. 2 and 3.