FIG. 2.

Numbers of hyphal strands in sections of ryegrass tillers infected with endophyte KS1. Three tillers with one mature leaf, three tillers with two mature leaves, and five tillers with three mature leaves were dissected and analyzed as described in Materials and Methods. Tillers are represented schematically in side view with age of leaves increasing from left to right; the emerging leaves, which are still growing, are on the very left. Shading of the sections of the individual leaves indicates the average numbers of hyphal strands per section, following the key provided as part of the figure (for instance, shading of the top section of the emerging leaf in the uppermost row indicates that the tips of emerging leaves have an average that falls between between 0 and 20 hyphal strands; the number of hyphae in a section of an individual tiller is the average of hyphal counts in cross sections taken from the top and the bottom of the section; marked by shading in Fig. 1). Shaded circles next to the sections indicate the standard deviation, according to the same key. The vertical arrows indicate the developmental fate of tissues as tillers develop more leaves (see Results for details).